initial commit

Signed-off-by: ale <ale@manalejandro.com>

kernel/src/advanced_perf.rs

@@ -0,0 +1,473 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Advanced performance monitoring and profiling system
+
+use alloc::{
+	collections::BTreeMap,
+	string::{String, ToString},
+	vec::Vec,
+};
+use core::sync::atomic::{AtomicBool, AtomicU64, Ordering};
+
+use crate::error::{Error, Result};
+use crate::sync::Spinlock;
+use crate::types::Jiffies;
+
+/// Performance counter types
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum CounterType {
+	CpuCycles,
+	Instructions,
+	CacheMisses,
+	PageFaults,
+	ContextSwitches,
+	SystemCalls,
+	Interrupts,
+	MemoryAllocations,
+	DiskReads,
+	DiskWrites,
+	NetworkPackets,
+	Custom(u32),
+}
+
+/// Performance event structure
+#[derive(Debug, Clone)]
+pub struct PerformanceEvent {
+	pub counter_type: CounterType,
+	pub value: u64,
+	pub timestamp: Jiffies,
+	pub process_id: Option<u32>,
+	pub thread_id: Option<u32>,
+	pub cpu_id: Option<u8>,
+}
+
+/// Performance counter
+#[derive(Debug)]
+pub struct PerformanceCounter {
+	pub counter_type: CounterType,
+	pub value: AtomicU64,
+	pub enabled: AtomicBool,
+	pub last_reset: AtomicU64,
+	pub description: String,
+}
+
+impl PerformanceCounter {
+	pub fn new(counter_type: CounterType, description: String) -> Self {
+		Self {
+			counter_type,
+			value: AtomicU64::new(0),
+			enabled: AtomicBool::new(true),
+			last_reset: AtomicU64::new(crate::time::get_jiffies().0),
+			description,
+		}
+	}
+
+	pub fn increment(&self, amount: u64) {
+		if self.enabled.load(Ordering::Relaxed) {
+			self.value.fetch_add(amount, Ordering::Relaxed);
+		}
+	}
+
+	pub fn get_value(&self) -> u64 {
+		self.value.load(Ordering::Relaxed)
+	}
+
+	pub fn reset(&self) {
+		self.value.store(0, Ordering::Relaxed);
+		self.last_reset
+			.store(crate::time::get_jiffies().0, Ordering::Relaxed);
+	}
+
+	pub fn enable(&self) {
+		self.enabled.store(true, Ordering::Relaxed);
+	}
+
+	pub fn disable(&self) {
+		self.enabled.store(false, Ordering::Relaxed);
+	}
+}
+
+/// Performance profiler for function/code block profiling
+#[derive(Debug)]
+pub struct Profiler {
+	pub name: String,
+	pub call_count: AtomicU64,
+	pub total_time: AtomicU64,
+	pub min_time: AtomicU64,
+	pub max_time: AtomicU64,
+	pub enabled: AtomicBool,
+}
+
+impl Profiler {
+	pub fn new(name: String) -> Self {
+		Self {
+			name,
+			call_count: AtomicU64::new(0),
+			total_time: AtomicU64::new(0),
+			min_time: AtomicU64::new(u64::MAX),
+			max_time: AtomicU64::new(0),
+			enabled: AtomicBool::new(true),
+		}
+	}
+
+	pub fn record_execution(&self, duration: u64) {
+		if !self.enabled.load(Ordering::Relaxed) {
+			return;
+		}
+
+		self.call_count.fetch_add(1, Ordering::Relaxed);
+		self.total_time.fetch_add(duration, Ordering::Relaxed);
+
+		// Update min time
+		let mut current_min = self.min_time.load(Ordering::Relaxed);
+		while duration < current_min {
+			match self.min_time.compare_exchange_weak(
+				current_min,
+				duration,
+				Ordering::Relaxed,
+				Ordering::Relaxed,
+			) {
+				Ok(_) => break,
+				Err(x) => current_min = x,
+			}
+		}
+
+		// Update max time
+		let mut current_max = self.max_time.load(Ordering::Relaxed);
+		while duration > current_max {
+			match self.max_time.compare_exchange_weak(
+				current_max,
+				duration,
+				Ordering::Relaxed,
+				Ordering::Relaxed,
+			) {
+				Ok(_) => break,
+				Err(x) => current_max = x,
+			}
+		}
+	}
+
+	pub fn get_stats(&self) -> ProfilerStats {
+		let call_count = self.call_count.load(Ordering::Relaxed);
+		let total_time = self.total_time.load(Ordering::Relaxed);
+
+		ProfilerStats {
+			name: self.name.clone(),
+			call_count,
+			total_time,
+			average_time: if call_count > 0 {
+				total_time / call_count
+			} else {
+				0
+			},
+			min_time: if call_count > 0 {
+				self.min_time.load(Ordering::Relaxed)
+			} else {
+				0
+			},
+			max_time: self.max_time.load(Ordering::Relaxed),
+		}
+	}
+
+	pub fn reset(&self) {
+		self.call_count.store(0, Ordering::Relaxed);
+		self.total_time.store(0, Ordering::Relaxed);
+		self.min_time.store(u64::MAX, Ordering::Relaxed);
+		self.max_time.store(0, Ordering::Relaxed);
+	}
+}
+
+/// Profiler statistics snapshot
+#[derive(Debug, Clone)]
+pub struct ProfilerStats {
+	pub name: String,
+	pub call_count: u64,
+	pub total_time: u64,
+	pub average_time: u64,
+	pub min_time: u64,
+	pub max_time: u64,
+}
+
+/// System-wide performance monitoring
+pub struct PerformanceMonitor {
+	counters: Spinlock<BTreeMap<CounterType, PerformanceCounter>>,
+	profilers: Spinlock<BTreeMap<String, Profiler>>,
+	events: Spinlock<Vec<PerformanceEvent>>,
+	max_events: usize,
+	monitoring_enabled: AtomicBool,
+}
+
+impl PerformanceMonitor {
+	pub const fn new() -> Self {
+		Self {
+			counters: Spinlock::new(BTreeMap::new()),
+			profilers: Spinlock::new(BTreeMap::new()),
+			events: Spinlock::new(Vec::new()),
+			max_events: 10000,
+			monitoring_enabled: AtomicBool::new(true),
+		}
+	}
+
+	/// Initialize default performance counters
+	pub fn init(&self) -> Result<()> {
+		let mut counters = self.counters.lock();
+
+		counters.insert(
+			CounterType::ContextSwitches,
+			PerformanceCounter::new(
+				CounterType::ContextSwitches,
+				"Context switches".to_string(),
+			),
+		);
+		counters.insert(
+			CounterType::SystemCalls,
+			PerformanceCounter::new(
+				CounterType::SystemCalls,
+				"System calls".to_string(),
+			),
+		);
+		counters.insert(
+			CounterType::Interrupts,
+			PerformanceCounter::new(
+				CounterType::Interrupts,
+				"Hardware interrupts".to_string(),
+			),
+		);
+		counters.insert(
+			CounterType::MemoryAllocations,
+			PerformanceCounter::new(
+				CounterType::MemoryAllocations,
+				"Memory allocations".to_string(),
+			),
+		);
+		counters.insert(
+			CounterType::PageFaults,
+			PerformanceCounter::new(CounterType::PageFaults, "Page faults".to_string()),
+		);
+
+		drop(counters);
+		crate::info!("Performance monitoring initialized");
+		Ok(())
+	}
+
+	/// Record performance event
+	pub fn record_event(&self, counter_type: CounterType, value: u64) {
+		if !self.monitoring_enabled.load(Ordering::Relaxed) {
+			return;
+		}
+
+		// Update counter
+		if let Some(counter) = self.counters.lock().get(&counter_type) {
+			counter.increment(value);
+		}
+
+		// Record event
+		let event = PerformanceEvent {
+			counter_type,
+			value,
+			timestamp: crate::time::get_jiffies(),
+			process_id: None, // TODO: Get current process ID
+			thread_id: None,  // TODO: Get current thread ID
+			cpu_id: None,     // TODO: Get current CPU ID
+		};
+
+		let mut events = self.events.lock();
+		if events.len() >= self.max_events {
+			events.remove(0); // Remove oldest event
+		}
+		events.push(event);
+	}
+
+	/// Get performance counter value
+	pub fn get_counter(&self, counter_type: CounterType) -> Option<u64> {
+		self.counters
+			.lock()
+			.get(&counter_type)
+			.map(|c| c.get_value())
+	}
+
+	/// Reset performance counter
+	pub fn reset_counter(&self, counter_type: CounterType) -> Result<()> {
+		match self.counters.lock().get(&counter_type) {
+			Some(counter) => {
+				counter.reset();
+				Ok(())
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Create or get profiler
+	pub fn get_profiler(&self, name: String) -> Result<()> {
+		let mut profilers = self.profilers.lock();
+		if !profilers.contains_key(&name) {
+			profilers.insert(name.clone(), Profiler::new(name));
+		}
+		Ok(())
+	}
+
+	/// Record profiler execution
+	pub fn record_profiler(&self, name: &str, duration: u64) -> Result<()> {
+		match self.profilers.lock().get(name) {
+			Some(profiler) => {
+				profiler.record_execution(duration);
+				Ok(())
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Get all profiler statistics
+	pub fn get_profiler_stats(&self) -> Vec<ProfilerStats> {
+		self.profilers
+			.lock()
+			.values()
+			.map(|p| p.get_stats())
+			.collect()
+	}
+
+	/// Get performance summary
+	pub fn get_summary(&self) -> PerformanceSummary {
+		let counters = self.counters.lock();
+		let counter_values: Vec<_> =
+			counters.iter().map(|(t, c)| (*t, c.get_value())).collect();
+		drop(counters);
+
+		let profiler_stats = self.get_profiler_stats();
+		let event_count = self.events.lock().len();
+
+		PerformanceSummary {
+			counters: counter_values,
+			profilers: profiler_stats,
+			total_events: event_count,
+			monitoring_enabled: self.monitoring_enabled.load(Ordering::Relaxed),
+		}
+	}
+
+	/// Enable/disable monitoring
+	pub fn set_monitoring(&self, enabled: bool) {
+		self.monitoring_enabled.store(enabled, Ordering::Relaxed);
+	}
+
+	/// Clear all events
+	pub fn clear_events(&self) {
+		self.events.lock().clear();
+	}
+
+	/// Reset all counters and profilers
+	pub fn reset_all(&self) {
+		for counter in self.counters.lock().values() {
+			counter.reset();
+		}
+
+		for profiler in self.profilers.lock().values() {
+			profiler.reset();
+		}
+
+		self.clear_events();
+	}
+}
+
+/// Performance summary structure
+#[derive(Debug, Clone)]
+pub struct PerformanceSummary {
+	pub counters: Vec<(CounterType, u64)>,
+	pub profilers: Vec<ProfilerStats>,
+	pub total_events: usize,
+	pub monitoring_enabled: bool,
+}
+
+/// RAII profiler guard for automatic timing
+pub struct ProfileGuard {
+	profiler_name: String,
+	start_time: u64,
+}
+
+impl ProfileGuard {
+	pub fn new(profiler_name: String) -> Result<Self> {
+		// Ensure profiler exists
+		PERFORMANCE_MONITOR.get_profiler(profiler_name.clone())?;
+
+		Ok(Self {
+			profiler_name,
+			start_time: crate::time::get_jiffies().0,
+		})
+	}
+}
+
+impl Drop for ProfileGuard {
+	fn drop(&mut self) {
+		let end_time = crate::time::get_jiffies().0;
+		let duration = end_time.saturating_sub(self.start_time);
+		let _ = PERFORMANCE_MONITOR.record_profiler(&self.profiler_name, duration);
+	}
+}
+
+/// Global performance monitor
+static PERFORMANCE_MONITOR: PerformanceMonitor = PerformanceMonitor::new();
+
+/// Initialize performance monitoring
+pub fn init_performance_monitoring() -> Result<()> {
+	PERFORMANCE_MONITOR.init()
+}
+
+/// Record performance event
+pub fn record_event(counter_type: CounterType, value: u64) {
+	PERFORMANCE_MONITOR.record_event(counter_type, value);
+}
+
+/// Get performance counter value
+pub fn get_counter(counter_type: CounterType) -> Option<u64> {
+	PERFORMANCE_MONITOR.get_counter(counter_type)
+}
+
+/// Reset performance counter
+pub fn reset_counter(counter_type: CounterType) -> Result<()> {
+	PERFORMANCE_MONITOR.reset_counter(counter_type)
+}
+
+/// Create profiler guard for automatic timing
+pub fn profile(name: String) -> Result<ProfileGuard> {
+	ProfileGuard::new(name)
+}
+
+/// Get performance summary
+pub fn get_performance_summary() -> PerformanceSummary {
+	PERFORMANCE_MONITOR.get_summary()
+}
+
+/// Enable/disable performance monitoring
+pub fn set_monitoring_enabled(enabled: bool) {
+	PERFORMANCE_MONITOR.set_monitoring(enabled);
+}
+
+/// Clear performance events
+pub fn clear_performance_events() {
+	PERFORMANCE_MONITOR.clear_events();
+}
+
+/// Reset all performance data
+pub fn reset_all_performance_data() {
+	PERFORMANCE_MONITOR.reset_all();
+}
+
+/// Profile function execution (returns RAII guard)
+pub fn profile_function(function_name: &str) -> Result<ProfileGuard> {
+	profile(function_name.to_string())
+}
+
+/// Convenience macros for performance monitoring
+#[macro_export]
+macro_rules! perf_counter {
+	($counter_type:expr, $value:expr) => {
+		$crate::advanced_perf::record_event($counter_type, $value);
+	};
+}
+
+#[macro_export]
+macro_rules! perf_profile {
+	($name:expr, $code:block) => {{
+		let _guard = $crate::advanced_perf::profile($name.to_string());
+		$code
+	}};
+}

kernel/src/arch/mod.rs

@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Architecture-specific code
+
+#[cfg(target_arch = "x86_64")]
+pub mod x86_64;
+
+// Other architectures can be added here when needed
+// #[cfg(target_arch = "aarch64")]
+// pub mod aarch64;
+
+// #[cfg(target_arch = "riscv64")]
+// pub mod riscv64;

kernel/src/arch/x86_64/boot.s

@@ -0,0 +1,296 @@
+# SPDX-License-Identifier: GPL-2.0
+# Rust Kernel boot entry point for x86_64
+
+.section .multiboot_header, "a"
+# Multiboot 1 Header
+.align 4
+    .long 0x1BADB002                # magic
+    .long 0x00000003                # flags (align + meminfo)
+    .long -(0x1BADB002 + 0x00000003) # checksum
+
+# Multiboot 2 Header
+.align 8
+header_start:
+    # Multiboot2 header
+    .long 0xe85250d6                # magic number
+    .long 0                         # architecture (i386)
+    .long header_end - header_start # header length
+    # checksum
+    .long -(0xe85250d6 + 0 + (header_end - header_start))
+    
+    # end tag
+    .word 0    # type
+    .word 0    # flags
+    .long 8    # size
+header_end:
+
+.section .bss
+# Multiboot information storage
+.section .bss
+multiboot_magic_store:
+    .skip 4
+multiboot_info_store:
+    .skip 4
+# Stack for the kernel
+.global stack_bottom
+.global stack_top
+stack_bottom:
+    .skip 16384  # 16 KiB stack
+stack_top:
+
+# Bootstrap page tables
+.align 4096
+.global boot_pml4
+boot_pml4:
+    .skip 4096
+
+.global boot_pdp
+boot_pdp:
+    .skip 4096
+
+.global boot_pd
+boot_pd:
+    .skip 4096
+
+.section .rodata
+gdt64:
+    .quad 0                     # null descriptor
+.set gdt64.code, . - gdt64
+    .quad (1<<44) | (1<<47) | (1<<41) | (1<<43) | (1<<53) # code segment
+.set gdt64.data, . - gdt64  
+    .quad (1<<44) | (1<<47) | (1<<41) # data segment
+gdt64.pointer:
+    .word . - gdt64 - 1         # length
+    .quad gdt64                 # address
+
+.section .text
+.global _start
+.code32
+_start:
+    # Set up stack
+    movl $stack_top, %esp
+    movl %esp, %ebp
+    
+    # Save multiboot information before we lose it or clobber EAX
+    movl %eax, multiboot_magic_store
+    movl %ebx, multiboot_info_store
+    
+    # Restore magic for check (or use stored value)
+    movl multiboot_magic_store, %eax
+
+    # Check for multiboot
+    cmpl $0x36d76289, %eax
+    je .multiboot_ok
+    cmpl $0x2BADB002, %eax
+    je .multiboot_ok
+    jmp no_multiboot
+
+.multiboot_ok:
+    
+    # Check for CPUID
+    call check_cpuid
+    test %eax, %eax
+    jz no_cpuid
+    
+    # Check for long mode
+    call check_long_mode
+    test %eax, %eax
+    jz no_long_mode
+    
+    # Set up page tables for long mode
+    call setup_page_tables
+    
+    # Enable PAE
+    movl %cr4, %eax
+    orl $1 << 5, %eax  # Set PAE bit
+    movl %eax, %cr4
+    
+    # Load page table
+    movl $boot_pml4, %eax
+    movl %eax, %cr3
+    
+    # Enable long mode
+    movl $0xC0000080, %ecx  # EFER MSR
+    rdmsr
+    orl $1 << 8, %eax       # Set LM bit
+    wrmsr
+    
+    # Enable paging
+    movl %cr0, %eax
+    orl $1 << 31, %eax      # Set PG bit
+    movl %eax, %cr0
+    
+    # Load GDT
+    lgdt gdt64.pointer
+    
+    # Far jump to 64-bit code
+    ljmp $gdt64.code, $start64
+
+check_cpuid:
+    # Try to flip the ID bit (bit 21) in FLAGS
+    pushfl
+    popl %eax
+    movl %eax, %ecx
+    xorl $1 << 21, %eax
+    pushl %eax
+    popfl
+    pushfl
+    popl %eax
+    pushl %ecx
+    popfl
+    cmpl %ecx, %eax
+    setne %al
+    movzbl %al, %eax
+    ret
+
+check_long_mode:
+    # Check if extended processor info is available
+    movl $0x80000000, %eax
+    cpuid
+    cmpl $0x80000001, %eax
+    jb .no_long_mode
+    
+    # Check if long mode is available
+    movl $0x80000001, %eax
+    cpuid
+    testl $1 << 29, %edx
+    setnz %al
+    movzbl %al, %eax
+    ret
+    
+.no_long_mode:
+    xorl %eax, %eax
+    ret
+
+setup_page_tables:
+    # Map PML4[0] -> PDP
+    movl $boot_pdp, %eax
+    orl $0b11, %eax     # present + writable
+    movl %eax, boot_pml4
+    
+    # Map PDP[0] -> PD
+    movl $boot_pd, %eax
+    orl $0b11, %eax     # present + writable
+    movl %eax, boot_pdp
+    
+    # Map PD[0..511] -> 2MB Pages (Identity map 0-1GB)
+    movl $boot_pd, %edi
+    movl $0, %ebx       # Physical address
+    movl $512, %ecx     # 512 entries
+    
+.map_pd_loop:
+    movl %ebx, %eax
+    orl $0b10000011, %eax # present + writable + huge (2MB)
+    movl %eax, (%edi)
+    addl $8, %edi       # Next entry
+    addl $0x200000, %ebx # Next 2MB
+    loop .map_pd_loop
+    
+    ret
+
+.code64
+start64:
+    # Set up segment registers
+    movw $gdt64.data, %ax
+    movw %ax, %ds
+    movw %ax, %es
+    movw %ax, %fs
+    movw %ax, %gs
+    movw %ax, %ss
+    
+    # Set up stack
+    movq $stack_top, %rsp
+    
+    # Clear the screen
+    call clear_screen
+    
+    # Print boot message
+    movq $boot_msg, %rsi
+    call print_string
+    
+    # Get multiboot parameters from saved locations
+    movl multiboot_magic_store, %edi  # multiboot magic -> first argument
+    movl multiboot_info_store, %esi   # multiboot info -> second argument
+    
+    # Call Rust kernel main with multiboot parameters
+    call kernel_main_multiboot
+    
+    # If we get here, halt
+halt:
+    cli
+    hlt
+    jmp halt
+
+# Clear VGA text buffer
+clear_screen:
+    movq $0xb8000, %rdi
+    movw $0x0f20, %ax  # White on black space
+    movl $2000, %ecx   # 80*25 characters
+    rep stosw
+    ret
+
+# Print string to VGA buffer
+# RSI = string pointer
+print_string:
+    movq $0xb8000, %rdi
+    movb $0x0f, %ah    # White on black
+.print_loop:
+    lodsb
+    testb %al, %al
+    jz .print_done
+    stosw
+    jmp .print_loop
+.print_done:
+    ret
+
+no_multiboot:
+    # DEBUG: Print 'M' to serial port COM1
+    mov $0x3f8, %dx
+    mov $'M', %al
+    out %al, %dx
+    movl $no_multiboot_msg, %esi
+    call print_string_32
+    jmp halt32
+
+no_cpuid:
+    movl $no_cpuid_msg, %esi
+    call print_string_32
+    jmp halt32
+    
+no_long_mode:
+    movl $no_long_mode_msg, %esi
+    call print_string_32
+    jmp halt32
+
+# 32-bit string printing
+print_string_32:
+    movl $0xb8000, %edi
+    movb $0x4f, %ah    # White on red
+.print_loop_32:
+    lodsb
+    testb %al, %al
+    jz .print_done_32
+    stosw
+    jmp .print_loop_32
+.print_done_32:
+    ret
+
+halt32:
+    cli
+    hlt
+    jmp halt32
+
+.section .rodata
+boot_msg:
+    .asciz "Rust Kernel booting..."
+
+no_multiboot_msg:
+    .asciz "ERROR: Not loaded by multiboot bootloader"
+    
+no_cpuid_msg:
+    .asciz "ERROR: CPUID not supported"
+    
+no_long_mode_msg:
+    .asciz "ERROR: Long mode not supported"
+
+

kernel/src/arch/x86_64/context.rs

@@ -0,0 +1,294 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Context switching for x86_64
+
+use core::arch::asm;
+
+/// CPU context for x86_64
+#[repr(C)]
+#[derive(Debug, Clone, Copy)]
+pub struct Context {
+	// General purpose registers
+	pub rax: u64,
+	pub rbx: u64,
+	pub rcx: u64,
+	pub rdx: u64,
+	pub rsi: u64,
+	pub rdi: u64,
+	pub rbp: u64,
+	pub rsp: u64,
+	pub r8: u64,
+	pub r9: u64,
+	pub r10: u64,
+	pub r11: u64,
+	pub r12: u64,
+	pub r13: u64,
+	pub r14: u64,
+	pub r15: u64,
+
+	// Control registers
+	pub rip: u64,
+	pub rflags: u64,
+	pub cr3: u64, // Page table base
+
+	// Segment selectors
+	pub cs: u16,
+	pub ds: u16,
+	pub es: u16,
+	pub fs: u16,
+	pub gs: u16,
+	pub ss: u16,
+
+	// FPU state (simplified)
+	pub fpu_state: [u8; 512], // FXSAVE area
+}
+
+impl Context {
+	pub fn new() -> Self {
+		Self {
+			rax: 0,
+			rbx: 0,
+			rcx: 0,
+			rdx: 0,
+			rsi: 0,
+			rdi: 0,
+			rbp: 0,
+			rsp: 0,
+			r8: 0,
+			r9: 0,
+			r10: 0,
+			r11: 0,
+			r12: 0,
+			r13: 0,
+			r14: 0,
+			r15: 0,
+			rip: 0,
+			rflags: 0x200, // Enable interrupts
+			cr3: 0,
+			cs: 0x08, // Kernel code segment
+			ds: 0x10,
+			es: 0x10,
+			fs: 0x10,
+			gs: 0x10,
+			ss: 0x10, // Kernel data segment
+			fpu_state: [0; 512],
+		}
+	}
+
+	/// Create a new kernel context
+	pub fn new_kernel(entry_point: u64, stack_ptr: u64, page_table: u64) -> Self {
+		let mut ctx = Self::new();
+		ctx.rip = entry_point;
+		ctx.rsp = stack_ptr;
+		ctx.cr3 = page_table;
+		ctx
+	}
+
+	/// Create a new user context
+	pub fn new_user(entry_point: u64, stack_ptr: u64, page_table: u64) -> Self {
+		let mut ctx = Self::new();
+		ctx.rip = entry_point;
+		ctx.rsp = stack_ptr;
+		ctx.cr3 = page_table;
+		ctx.cs = 0x18 | 3; // User code segment with RPL=3
+		ctx.ds = 0x20 | 3; // User data segment with RPL=3
+		ctx.es = 0x20 | 3;
+		ctx.fs = 0x20 | 3;
+		ctx.gs = 0x20 | 3;
+		ctx.ss = 0x20 | 3;
+		ctx.rflags |= 0x200; // Enable interrupts in user mode
+		ctx
+	}
+
+	/// Save current CPU context
+	pub fn save_current(&mut self) {
+		unsafe {
+			// Save registers in smaller groups to avoid register pressure
+			asm!(
+			    "mov {}, rax",
+			    "mov {}, rbx",
+			    "mov {}, rcx",
+			    "mov {}, rdx",
+			    out(reg) self.rax,
+			    out(reg) self.rbx,
+			    out(reg) self.rcx,
+			    out(reg) self.rdx,
+			);
+
+			asm!(
+			    "mov {}, rsi",
+			    "mov {}, rdi",
+			    "mov {}, rbp",
+			    "mov {}, rsp",
+			    out(reg) self.rsi,
+			    out(reg) self.rdi,
+			    out(reg) self.rbp,
+			    out(reg) self.rsp,
+			);
+
+			asm!(
+			    "mov {}, r8",
+			    "mov {}, r9",
+			    "mov {}, r10",
+			    "mov {}, r11",
+			    out(reg) self.r8,
+			    out(reg) self.r9,
+			    out(reg) self.r10,
+			    out(reg) self.r11,
+			);
+
+			asm!(
+			    "mov {}, r12",
+			    "mov {}, r13",
+			    "mov {}, r14",
+			    "mov {}, r15",
+			    out(reg) self.r12,
+			    out(reg) self.r13,
+			    out(reg) self.r14,
+			    out(reg) self.r15,
+			);
+
+			// Save flags
+			asm!("pushfq; pop {}", out(reg) self.rflags);
+
+			// Save CR3 (page table)
+			asm!("mov {}, cr3", out(reg) self.cr3);
+
+			// Save segment registers
+			asm!("mov {0:x}, cs", out(reg) self.cs);
+			asm!("mov {0:x}, ds", out(reg) self.ds);
+			asm!("mov {0:x}, es", out(reg) self.es);
+			asm!("mov {0:x}, fs", out(reg) self.fs);
+			asm!("mov {0:x}, gs", out(reg) self.gs);
+			asm!("mov {0:x}, ss", out(reg) self.ss);
+		}
+	}
+
+	/// Restore CPU context and switch to it
+	pub unsafe fn restore(&self) -> ! {
+		// Restore context using the pointer to self (passed in rdi)
+		asm!(
+			// Restore CR3 (Page Table)
+			"mov rax, [rdi + 144]",
+			"mov cr3, rax",
+
+			// Switch stack to the target stack
+			"mov rsp, [rdi + 56]",
+
+			// Construct interrupt stack frame for iretq
+			// Stack layout: SS, RSP, RFLAGS, CS, RIP
+
+			// SS
+			"movzx rax, word ptr [rdi + 162]",
+			"push rax",
+
+			// RSP (target stack pointer)
+			"mov rax, [rdi + 56]",
+			"push rax",
+
+			// RFLAGS
+			"mov rax, [rdi + 136]",
+			"push rax",
+
+			// CS
+			"movzx rax, word ptr [rdi + 152]",
+			"push rax",
+
+			// RIP
+			"mov rax, [rdi + 128]",
+			"push rax",
+
+			// Push General Purpose Registers onto the new stack
+			// We push them in reverse order of popping
+			"push qword ptr [rdi + 0]",   // rax
+			"push qword ptr [rdi + 8]",   // rbx
+			"push qword ptr [rdi + 16]",  // rcx
+			"push qword ptr [rdi + 24]",  // rdx
+			"push qword ptr [rdi + 32]",  // rsi
+			"push qword ptr [rdi + 40]",  // rdi
+			"push qword ptr [rdi + 48]",  // rbp
+			// rsp is handled by stack switch
+			"push qword ptr [rdi + 64]",  // r8
+			"push qword ptr [rdi + 72]",  // r9
+			"push qword ptr [rdi + 80]",  // r10
+			"push qword ptr [rdi + 88]",  // r11
+			"push qword ptr [rdi + 96]",  // r12
+			"push qword ptr [rdi + 104]", // r13
+			"push qword ptr [rdi + 112]", // r14
+			"push qword ptr [rdi + 120]", // r15
+
+			// Restore Segment Registers
+			"mov ax, [rdi + 154]", // ds
+			"mov ds, ax",
+			"mov ax, [rdi + 156]", // es
+			"mov es, ax",
+			"mov ax, [rdi + 158]", // fs
+			"mov fs, ax",
+			"mov ax, [rdi + 160]", // gs
+			"mov gs, ax",
+
+			// Pop General Purpose Registers
+			"pop r15",
+			"pop r14",
+			"pop r13",
+			"pop r12",
+			"pop r11",
+			"pop r10",
+			"pop r9",
+			"pop r8",
+			"pop rbp",
+			"pop rdi", // This restores the target rdi
+			"pop rsi",
+			"pop rdx",
+			"pop rcx",
+			"pop rbx",
+			"pop rax",
+
+			// Return from interrupt (restores RIP, CS, RFLAGS, RSP, SS)
+			"iretq",
+			in("rdi") self,
+			options(noreturn)
+		);
+	}
+}
+
+/// Context switch from old context to new context
+pub unsafe fn switch_context(old_ctx: &mut Context, new_ctx: &Context) {
+	// Save current context
+	old_ctx.save_current();
+
+	// Restore new context
+	new_ctx.restore();
+}
+
+/// Get current stack pointer
+pub fn get_current_stack_pointer() -> u64 {
+	let rsp: u64;
+	unsafe {
+		asm!("mov {}, rsp", out(reg) rsp);
+	}
+	rsp
+}
+
+/// Get current instruction pointer (return address)
+pub fn get_current_instruction_pointer() -> u64 {
+	let rip: u64;
+	unsafe {
+		asm!("lea {}, [rip]", out(reg) rip);
+	}
+	rip
+}
+
+/// Save FPU state
+pub fn save_fpu_state(buffer: &mut [u8; 512]) {
+	unsafe {
+		asm!("fxsave [{}]", in(reg) buffer.as_mut_ptr());
+	}
+}
+
+/// Restore FPU state
+pub fn restore_fpu_state(buffer: &[u8; 512]) {
+	unsafe {
+		asm!("fxrstor [{}]", in(reg) buffer.as_ptr());
+	}
+}

kernel/src/arch/x86_64/gdt.rs

@@ -0,0 +1,156 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Global Descriptor Table (GDT) for x86_64
+
+use core::mem::size_of;
+
+/// GDT Entry structure
+#[derive(Debug, Clone, Copy)]
+#[repr(C, packed)]
+pub struct GdtEntry {
+	pub limit_low: u16,
+	pub base_low: u16,
+	pub base_middle: u8,
+	pub access: u8,
+	pub granularity: u8,
+	pub base_high: u8,
+}
+
+impl GdtEntry {
+	pub const fn new() -> Self {
+		Self {
+			limit_low: 0,
+			base_low: 0,
+			base_middle: 0,
+			access: 0,
+			granularity: 0,
+			base_high: 0,
+		}
+	}
+
+	pub fn set_segment(&mut self, base: u32, limit: u32, access: u8, granularity: u8) {
+		self.base_low = (base & 0xFFFF) as u16;
+		self.base_middle = ((base >> 16) & 0xFF) as u8;
+		self.base_high = ((base >> 24) & 0xFF) as u8;
+
+		self.limit_low = (limit & 0xFFFF) as u16;
+		self.granularity = ((limit >> 16) & 0x0F) as u8 | (granularity & 0xF0);
+
+		self.access = access;
+	}
+}
+
+/// GDT Pointer structure
+#[derive(Debug, Clone, Copy)]
+#[repr(C, packed)]
+pub struct GdtPointer {
+	pub limit: u16,
+	pub base: u64,
+}
+
+/// GDT constants
+pub const GDT_ENTRIES: usize = 5;
+
+/// GDT access byte flags
+pub mod access {
+	pub const PRESENT: u8 = 1 << 7;
+	pub const RING_0: u8 = 0 << 5;
+	pub const RING_1: u8 = 1 << 5;
+	pub const RING_2: u8 = 2 << 5;
+	pub const RING_3: u8 = 3 << 5;
+	pub const SYSTEM: u8 = 1 << 4;
+	pub const EXECUTABLE: u8 = 1 << 3;
+	pub const CONFORMING: u8 = 1 << 2;
+	pub const READABLE: u8 = 1 << 1;
+	pub const WRITABLE: u8 = 1 << 1;
+	pub const ACCESSED: u8 = 1 << 0;
+}
+
+/// GDT granularity flags
+pub mod granularity {
+	pub const GRANULARITY_4K: u8 = 1 << 7;
+	pub const SIZE_32: u8 = 1 << 6;
+	pub const LONG_MODE: u8 = 1 << 5;
+}
+
+/// Global GDT
+static mut GDT: [GdtEntry; GDT_ENTRIES] = [GdtEntry::new(); GDT_ENTRIES];
+
+/// Initialize GDT
+pub fn init() {
+	unsafe {
+		// Null descriptor
+		GDT[0] = GdtEntry::new();
+
+		// Kernel code segment (64-bit)
+		GDT[1].set_segment(
+			0x00000000,
+			0xFFFFF,
+			access::PRESENT
+				| access::RING_0 | access::SYSTEM
+				| access::EXECUTABLE | access::READABLE,
+			granularity::GRANULARITY_4K | granularity::LONG_MODE,
+		);
+
+		// Kernel data segment (64-bit)
+		GDT[2].set_segment(
+			0x00000000,
+			0xFFFFF,
+			access::PRESENT | access::RING_0 | access::SYSTEM | access::WRITABLE,
+			granularity::GRANULARITY_4K | granularity::LONG_MODE,
+		);
+
+		// User code segment (64-bit)
+		GDT[3].set_segment(
+			0x00000000,
+			0xFFFFF,
+			access::PRESENT
+				| access::RING_3 | access::SYSTEM
+				| access::EXECUTABLE | access::READABLE,
+			granularity::GRANULARITY_4K | granularity::LONG_MODE,
+		);
+
+		// User data segment (64-bit)
+		GDT[4].set_segment(
+			0x00000000,
+			0xFFFFF,
+			access::PRESENT | access::RING_3 | access::SYSTEM | access::WRITABLE,
+			granularity::GRANULARITY_4K | granularity::LONG_MODE,
+		);
+
+		let gdt_ptr = GdtPointer {
+			limit: (size_of::<[GdtEntry; GDT_ENTRIES]>() - 1) as u16,
+			base: GDT.as_ptr() as u64,
+		};
+
+		// Load GDT
+		core::arch::asm!(
+		    "lgdt [{}]",
+		    in(reg) &gdt_ptr,
+		    options(nostack, preserves_flags)
+		);
+
+		// Reload segment registers
+		core::arch::asm!(
+		    "mov ax, 0x10",  // Kernel data segment
+		    "mov ds, ax",
+		    "mov es, ax",
+		    "mov fs, ax",
+		    "mov gs, ax",
+		    "mov ss, ax",
+		    out("ax") _,
+		    options(nostack, preserves_flags)
+		);
+
+		// Far jump to reload CS
+		core::arch::asm!(
+		    "push 0x08",     // Kernel code segment
+		    "lea rax, [rip + 2f]",
+		    "push rax",
+		    "retfq",
+		    "2:",
+		    out("rax") _,
+		    options(nostack, preserves_flags)
+		);
+	}
+}

kernel/src/arch/x86_64/mod.rs

@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! x86_64 architecture support
+
+pub mod context;
+pub mod gdt;
+pub mod idt;
+pub mod paging;
+pub mod pic;
+pub mod port;

kernel/src/arch/x86_64/paging.rs

@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Paging stub
+pub fn init() {}

kernel/src/arch/x86_64/pic.rs

@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Programmable Interrupt Controller (8259 PIC) support
+
+use crate::arch::x86_64::port::Port;
+
+/// Primary PIC ports
+const PIC1_COMMAND: u16 = 0x20;
+const PIC1_DATA: u16 = 0x21;
+
+/// Secondary PIC ports  
+const PIC2_COMMAND: u16 = 0xA0;
+const PIC2_DATA: u16 = 0xA1;
+
+/// PIC commands
+const PIC_EOI: u8 = 0x20; // End of Interrupt
+
+/// Initialize the PIC
+pub unsafe fn init_pic() {
+	let mut pic1_command = Port::new(PIC1_COMMAND);
+	let mut pic1_data = Port::new(PIC1_DATA);
+	let mut pic2_command = Port::new(PIC2_COMMAND);
+	let mut pic2_data = Port::new(PIC2_DATA);
+
+	// Save masks
+	let mask1 = pic1_data.read() as u8;
+	let mask2 = pic2_data.read() as u8;
+
+	// Initialize PIC1
+	pic1_command.write(0x11); // ICW1: Initialize + expect ICW4
+	io_wait();
+	pic1_data.write(0x20); // ICW2: PIC1 offset (32)
+	io_wait();
+	pic1_data.write(0x04); // ICW3: Tell PIC1 there's a PIC2 at IRQ2
+	io_wait();
+	pic1_data.write(0x01); // ICW4: 8086 mode
+	io_wait();
+
+	// Initialize PIC2
+	pic2_command.write(0x11); // ICW1: Initialize + expect ICW4
+	io_wait();
+	pic2_data.write(0x28); // ICW2: PIC2 offset (40)
+	io_wait();
+	pic2_data.write(0x02); // ICW3: Tell PIC2 it's at IRQ2 of PIC1
+	io_wait();
+	pic2_data.write(0x01); // ICW4: 8086 mode
+	io_wait();
+
+	// Restore masks
+	pic1_data.write(mask1 as u32);
+	pic2_data.write(mask2 as u32);
+}
+
+/// Send End of Interrupt signal
+pub unsafe fn send_eoi(irq: u8) {
+	let mut pic1_command = Port::new(PIC1_COMMAND);
+	let mut pic2_command = Port::new(PIC2_COMMAND);
+
+	if irq >= 8 {
+		pic2_command.write(PIC_EOI as u32);
+	}
+	pic1_command.write(PIC_EOI as u32);
+}
+
+/// Mask (disable) an IRQ
+pub unsafe fn mask_irq(irq: u8) {
+	let port = if irq < 8 { PIC1_DATA } else { PIC2_DATA };
+
+	let mut data_port = Port::new(port);
+	let value = data_port.read() as u8;
+	let mask = 1 << (irq % 8);
+	data_port.write((value | mask) as u32);
+}
+
+/// Unmask (enable) an IRQ
+pub unsafe fn unmask_irq(irq: u8) {
+	let port = if irq < 8 { PIC1_DATA } else { PIC2_DATA };
+
+	let mut data_port = Port::new(port);
+	let value = data_port.read() as u8;
+	let mask = 1 << (irq % 8);
+	data_port.write((value & !mask) as u32);
+}
+
+/// I/O wait - small delay for old hardware
+unsafe fn io_wait() {
+	let mut port = Port::new(0x80);
+	port.write(0);
+}

kernel/src/arch/x86_64/port.rs

@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Port I/O operations
+
+use core::arch::asm;
+
+/// Port I/O wrapper
+pub struct Port {
+	port: u16,
+}
+
+impl Port {
+	pub const fn new(port: u16) -> Self {
+		Self { port }
+	}
+
+	pub unsafe fn write(&mut self, value: u32) {
+		asm!(
+		    "out dx, eax",
+		    in("dx") self.port,
+		    in("eax") value,
+		);
+	}
+
+	pub unsafe fn read(&mut self) -> u32 {
+		let value: u32;
+		asm!(
+		    "in eax, dx",
+		    out("eax") value,
+		    in("dx") self.port,
+		);
+		value
+	}
+}
+
+/// Read a byte from a port
+pub unsafe fn inb(port: u16) -> u8 {
+	let value: u8;
+	asm!(
+	    "in al, dx",
+	    out("al") value,
+	    in("dx") port,
+	    options(nomem, nostack, preserves_flags)
+	);
+	value
+}
+
+/// Write a byte to a port
+pub unsafe fn outb(port: u16, value: u8) {
+	asm!(
+	    "out dx, al",
+	    in("dx") port,
+	    in("al") value,
+	    options(nomem, nostack, preserves_flags)
+	);
+}
+
+/// Output a 32-bit value to a port
+pub unsafe fn outl(port: u16, value: u32) {
+	asm!(
+	    "out dx, eax",
+	    in("dx") port,
+	    in("eax") value,
+	    options(nostack, preserves_flags)
+	);
+}
+
+/// Input a 32-bit value from a port
+pub unsafe fn inl(port: u16) -> u32 {
+	let value: u32;
+	asm!(
+	    "in eax, dx",
+	    in("dx") port,
+	    out("eax") value,
+	    options(nostack, preserves_flags)
+	);
+	value
+}

kernel/src/arp.rs

@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! ARP (Address Resolution Protocol) implementation.
+
+use crate::error::{Error, Result};
+use crate::network::{Ipv4Address, MacAddress};
+use alloc::vec::Vec;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ArpOperation {
+	Request = 1,
+	Reply = 2,
+}
+
+#[derive(Debug, Clone, Copy)]
+#[repr(C, packed)]
+pub struct ArpPacket {
+	pub htype: [u8; 2],
+	pub ptype: [u8; 2],
+	pub hlen: u8,
+	pub plen: u8,
+	pub oper: [u8; 2],
+	pub sha: MacAddress,
+	pub spa: Ipv4Address,
+	pub tha: MacAddress,
+	pub tpa: Ipv4Address,
+}
+
+impl ArpPacket {
+	pub fn new(
+		oper: ArpOperation,
+		sha: MacAddress,
+		spa: Ipv4Address,
+		tha: MacAddress,
+		tpa: Ipv4Address,
+	) -> Self {
+		Self {
+			htype: (1 as u16).to_be_bytes(),      // Ethernet
+			ptype: (0x0800 as u16).to_be_bytes(), // IPv4
+			hlen: 6,
+			plen: 4,
+			oper: (oper as u16).to_be_bytes(),
+			sha,
+			spa,
+			tha,
+			tpa,
+		}
+	}
+
+	pub fn to_bytes(&self) -> Vec<u8> {
+		let mut bytes = Vec::with_capacity(28);
+		bytes.extend_from_slice(&self.htype);
+		bytes.extend_from_slice(&self.ptype);
+		bytes.push(self.hlen);
+		bytes.push(self.plen);
+		bytes.extend_from_slice(&self.oper);
+		bytes.extend_from_slice(self.sha.bytes());
+		bytes.extend_from_slice(self.spa.bytes());
+		bytes.extend_from_slice(self.tha.bytes());
+		bytes.extend_from_slice(self.tpa.bytes());
+		bytes
+	}
+
+	pub fn from_bytes(bytes: &[u8]) -> Result<Self> {
+		if bytes.len() < 28 {
+			return Err(Error::InvalidArgument);
+		}
+		let mut htype = [0u8; 2];
+		htype.copy_from_slice(&bytes[0..2]);
+		let mut ptype = [0u8; 2];
+		ptype.copy_from_slice(&bytes[2..4]);
+		let hlen = bytes[4];
+		let plen = bytes[5];
+		let mut oper = [0u8; 2];
+		oper.copy_from_slice(&bytes[6..8]);
+		let mut sha_bytes = [0u8; 6];
+		sha_bytes.copy_from_slice(&bytes[8..14]);
+		let mut spa_bytes = [0u8; 4];
+		spa_bytes.copy_from_slice(&bytes[14..18]);
+		let mut tha_bytes = [0u8; 6];
+		tha_bytes.copy_from_slice(&bytes[18..24]);
+		let mut tpa_bytes = [0u8; 4];
+		tpa_bytes.copy_from_slice(&bytes[24..28]);
+
+		Ok(Self {
+			htype,
+			ptype,
+			hlen,
+			plen,
+			oper,
+			sha: MacAddress::new(sha_bytes),
+			spa: Ipv4Address::from_bytes(spa_bytes),
+			tha: MacAddress::new(tha_bytes),
+			tpa: Ipv4Address::from_bytes(tpa_bytes),
+		})
+	}
+}

kernel/src/benchmark.rs

@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel benchmark system
+
+use alloc::{
+	string::{String, ToString},
+	vec,
+	vec::Vec,
+};
+
+use crate::error::Result;
+use crate::time::{get_jiffies, monotonic_time};
+use crate::{info, warn};
+
+/// Benchmark result
+#[derive(Debug, Clone)]
+pub struct BenchmarkResult {
+	pub name: String,
+	pub iterations: u64,
+	pub total_time_ns: u64,
+	pub avg_time_ns: u64,
+	pub min_time_ns: u64,
+	pub max_time_ns: u64,
+}
+
+impl BenchmarkResult {
+	pub fn new(name: String, iterations: u64, times: &[u64]) -> Self {
+		let total_time_ns = times.iter().sum();
+		let avg_time_ns = total_time_ns / iterations;
+		let min_time_ns = *times.iter().min().unwrap_or(&0);
+		let max_time_ns = *times.iter().max().unwrap_or(&0);
+
+		Self {
+			name,
+			iterations,
+			total_time_ns,
+			avg_time_ns,
+			min_time_ns,
+			max_time_ns,
+		}
+	}
+
+	pub fn print(&self) {
+		info!("Benchmark: {}", self.name);
+		info!("  Iterations: {}", self.iterations);
+		info!("  Total time: {} ns", self.total_time_ns);
+		info!("  Average time: {} ns", self.avg_time_ns);
+		info!("  Min time: {} ns", self.min_time_ns);
+		info!("  Max time: {} ns", self.max_time_ns);
+	}
+}
+
+/// Benchmark function type
+pub type BenchmarkFn = fn();
+
+/// Run a benchmark
+pub fn benchmark(name: &str, iterations: u64, func: BenchmarkFn) -> BenchmarkResult {
+	let mut times = Vec::new();
+
+	info!("Running benchmark: {} ({} iterations)", name, iterations);
+
+	for _i in 0..iterations {
+		let start = monotonic_time();
+		func();
+		let end = monotonic_time();
+
+		let elapsed_ns = (end.to_ns() as i64 - start.to_ns() as i64) as u64;
+		times.push(elapsed_ns);
+	}
+
+	let result = BenchmarkResult::new(name.to_string(), iterations, &times);
+	result.print();
+	result
+}
+
+/// Memory allocation benchmark
+fn bench_memory_alloc() {
+	let _vec: Vec<u8> = Vec::with_capacity(1024);
+}
+
+/// Memory deallocation benchmark
+fn bench_memory_dealloc() {
+	let vec: Vec<u8> = Vec::with_capacity(1024);
+	drop(vec);
+}
+
+/// Simple arithmetic benchmark
+fn bench_arithmetic() {
+	let mut result = 0u64;
+	for i in 0..1000 {
+		result = result.wrapping_add(i).wrapping_mul(2);
+	}
+	// Prevent optimization
+	core::hint::black_box(result);
+}
+
+/// String operations benchmark
+fn bench_string_ops() {
+	let mut s = String::new();
+	for i in 0..100 {
+		s.push_str("test");
+		s.push((b'0' + (i % 10) as u8) as char);
+	}
+	core::hint::black_box(s);
+}
+
+/// Interrupt enable/disable benchmark
+fn bench_interrupt_toggle() {
+	crate::interrupt::disable();
+	crate::interrupt::enable();
+}
+
+/// Run all kernel benchmarks
+pub fn run_all_benchmarks() -> Result<Vec<BenchmarkResult>> {
+	info!("Running kernel performance benchmarks");
+
+	let mut results = Vec::new();
+
+	// Memory benchmarks
+	results.push(benchmark("memory_alloc", 1000, bench_memory_alloc));
+	results.push(benchmark("memory_dealloc", 1000, bench_memory_dealloc));
+
+	// CPU benchmarks
+	results.push(benchmark("arithmetic", 100, bench_arithmetic));
+	results.push(benchmark("string_ops", 100, bench_string_ops));
+
+	// System call benchmarks
+	results.push(benchmark("interrupt_toggle", 1000, bench_interrupt_toggle));
+
+	info!("Benchmark suite completed");
+	Ok(results)
+}
+
+/// Run specific benchmark
+pub fn run_benchmark(name: &str, iterations: u64) -> Result<BenchmarkResult> {
+	match name {
+		"memory_alloc" => Ok(benchmark(name, iterations, bench_memory_alloc)),
+		"memory_dealloc" => Ok(benchmark(name, iterations, bench_memory_dealloc)),
+		"arithmetic" => Ok(benchmark(name, iterations, bench_arithmetic)),
+		"string_ops" => Ok(benchmark(name, iterations, bench_string_ops)),
+		"interrupt_toggle" => Ok(benchmark(name, iterations, bench_interrupt_toggle)),
+		_ => {
+			warn!("Unknown benchmark: {}", name);
+			Err(crate::error::Error::NotFound)
+		}
+	}
+}
+
+/// Get available benchmarks
+pub fn list_benchmarks() -> Vec<&'static str> {
+	vec![
+		"memory_alloc",
+		"memory_dealloc",
+		"arithmetic",
+		"string_ops",
+		"interrupt_toggle",
+	]
+}
+
+/// Performance stress test
+pub fn stress_test(duration_seconds: u64) -> Result<()> {
+	info!("Running stress test for {} seconds", duration_seconds);
+
+	let start_jiffies = get_jiffies();
+	let target_jiffies = start_jiffies.0 + (duration_seconds * crate::time::HZ);
+
+	let mut iterations = 0u64;
+
+	while get_jiffies().0 < target_jiffies {
+		// Mix of different operations
+		bench_arithmetic();
+		bench_memory_alloc();
+		bench_string_ops();
+		bench_interrupt_toggle();
+
+		iterations += 1;
+
+		// Yield occasionally to prevent monopolizing CPU
+		if iterations % 1000 == 0 {
+			crate::kthread::kthread_yield();
+		}
+	}
+
+	let elapsed_jiffies = get_jiffies().0 - start_jiffies.0;
+	let ops_per_second = (iterations * crate::time::HZ) / elapsed_jiffies;
+
+	info!("Stress test completed:");
+	info!("  Duration: {} jiffies", elapsed_jiffies);
+	info!("  Total iterations: {}", iterations);
+	info!("  Operations per second: {}", ops_per_second);
+
+	Ok(())
+}

kernel/src/boot.rs

@@ -0,0 +1,345 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Boot process and hardware initialization
+
+use alloc::string::ToString;
+
+use crate::error::Result;
+use crate::{error, info};
+
+/// Boot stages
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum BootStage {
+	EarlyInit,
+	MemoryInit,
+	DeviceInit,
+	SchedulerInit,
+	FileSystemInit,
+	NetworkInit,
+	UserSpaceInit,
+	Complete,
+}
+
+/// Boot information structure
+#[derive(Debug)]
+pub struct BootInfo {
+	pub memory_size: usize,
+	pub available_memory: usize,
+	pub cpu_count: usize,
+	pub boot_time: u64,
+	pub command_line: Option<alloc::string::String>,
+	pub initrd_start: Option<usize>,
+	pub initrd_size: Option<usize>,
+	pub multiboot_addr: Option<usize>,
+}
+
+impl BootInfo {
+	pub fn new() -> Self {
+		Self {
+			memory_size: 0,
+			available_memory: 0,
+			cpu_count: 1,
+			boot_time: 0,
+			command_line: None,
+			initrd_start: None,
+			initrd_size: None,
+			multiboot_addr: None,
+		}
+	}
+}
+
+/// Global boot information
+pub static mut BOOT_INFO: BootInfo = BootInfo {
+	memory_size: 0,
+	available_memory: 0,
+	cpu_count: 1,
+	boot_time: 0,
+	command_line: None,
+	initrd_start: None,
+	initrd_size: None,
+	multiboot_addr: None,
+};
+
+/// Set multiboot information address
+pub fn set_multiboot_info(addr: usize) {
+	unsafe {
+		BOOT_INFO.multiboot_addr = Some(addr);
+	}
+}
+
+/// Get boot information
+pub fn get_boot_info() -> &'static BootInfo {
+	unsafe { &BOOT_INFO }
+}
+
+/// Update boot information
+pub unsafe fn update_boot_info<F>(f: F)
+where
+	F: FnOnce(&mut BootInfo),
+{
+	f(&mut BOOT_INFO);
+}
+
+pub mod multiboot {
+	use crate::error::Result;
+	use crate::info;
+	use crate::types::{PhysAddr, VirtAddr};
+
+	/// Multiboot2 information structure
+	#[repr(C)]
+	pub struct MultibootInfo {
+		pub total_size: u32,
+		pub reserved: u32,
+	}
+
+	/// Memory map entry from multiboot
+	#[repr(C)]
+	#[derive(Debug, Clone, Copy)]
+	pub struct MemoryMapEntry {
+		pub base_addr: u64,
+		pub length: u64,
+		pub type_: u32,
+		pub reserved: u32,
+	}
+
+	/// Memory map types
+	pub mod memory_type {
+		pub const AVAILABLE: u32 = 1;
+		pub const RESERVED: u32 = 2;
+		pub const ACPI_RECLAIMABLE: u32 = 3;
+		pub const NVS: u32 = 4;
+		pub const BADRAM: u32 = 5;
+	}
+
+	/// Boot memory information
+	#[derive(Debug)]
+	pub struct BootMemoryInfo {
+		pub total_memory: u64,
+		pub available_memory: u64,
+		pub memory_regions: [MemoryMapEntry; 32],
+		pub region_count: usize,
+	}
+
+	impl BootMemoryInfo {
+		pub fn new() -> Self {
+			Self {
+				total_memory: 0,
+				available_memory: 0,
+				memory_regions: [MemoryMapEntry {
+					base_addr: 0,
+					length: 0,
+					type_: 0,
+					reserved: 0,
+				}; 32],
+				region_count: 0,
+			}
+		}
+
+		pub fn add_region(&mut self, entry: MemoryMapEntry) {
+			if entry.type_ == memory_type::AVAILABLE {
+				self.available_memory += entry.length;
+			}
+			self.total_memory += entry.length;
+			if self.region_count < 32 {
+				self.memory_regions[self.region_count] = entry;
+				self.region_count += 1;
+			}
+		}
+	}
+
+	/// Parse multiboot2 information and initialize memory management
+	pub fn init_memory_from_multiboot(multiboot_addr: usize) -> Result<()> {
+		crate::console::write_str("Parsing multiboot\n");
+
+		// Validate multiboot address is in identity-mapped range (0-1GB)
+		if multiboot_addr >= 0x40000000 {
+			// 1GB
+			crate::console::write_str("ERROR: multiboot addr out of range\n");
+			return Err(crate::error::Error::InvalidArgument);
+		}
+
+		crate::console::write_str("Multiboot addr validated\n");
+
+		let multiboot_info = unsafe { &*(multiboot_addr as *const MultibootInfo) };
+
+		crate::console::write_str("Got multiboot info\n");
+
+		// Parse memory map from multiboot info
+		let mut memory_info = BootMemoryInfo::new();
+
+		crate::console::write_str("Created BootMemoryInfo\n");
+
+		// For now, assume a basic memory layout if we can't parse multiboot properly
+		// This is a fallback to make the kernel bootable
+		let default_memory = MemoryMapEntry {
+			base_addr: 0x100000, // 1MB
+			length: 0x7F00000,   // ~127MB (assuming 128MB total RAM)
+			type_: memory_type::AVAILABLE,
+			reserved: 0,
+		};
+
+		crate::console::write_str("Adding default memory region\n");
+		memory_info.add_region(default_memory);
+
+		// Update global boot info
+		unsafe {
+			super::update_boot_info(|boot_info| {
+				boot_info.memory_size = memory_info.total_memory as usize;
+				boot_info.available_memory = memory_info.available_memory as usize;
+			});
+		}
+
+		// Initialize page allocator with available memory
+		// Note: Only first 1GB is identity-mapped in boot.s
+		const MAX_IDENTITY_MAPPED: u64 = 1024 * 1024 * 1024; // 1GB
+
+		crate::console::write_str("Processing memory regions\n");
+
+		for i in 0..memory_info.region_count {
+			crate::console::write_str("Region loop iteration\n");
+			let region = &memory_info.memory_regions[i];
+
+			if region.type_ == memory_type::AVAILABLE {
+				let start_addr = region.base_addr;
+				let end_addr = region.base_addr + region.length;
+
+				crate::console::write_str("Available region found\n");
+
+				// Clamp to identity-mapped region
+				let safe_start = start_addr.max(0x100000); // Skip first 1MB (BIOS/kernel)
+				let safe_end = end_addr.min(MAX_IDENTITY_MAPPED);
+
+				crate::console::write_str("Clamped region\n");
+
+				if safe_start >= safe_end {
+					crate::console::write_str("Skipping invalid range\n");
+					continue; // Skip invalid/unmapped region
+				}
+
+				crate::console::write_str("About to call add_free_range\n");
+				// Add this memory region to the page allocator
+				crate::memory::page::add_free_range(
+					PhysAddr::new(safe_start as usize),
+					PhysAddr::new(safe_end as usize),
+				)?;
+				crate::console::write_str("Successfully added free range\n");
+			}
+		}
+
+		crate::console::write_str("Memory init completed\n");
+
+		Ok(())
+	}
+}
+
+/// Early boot setup before memory allocation is available
+pub fn early_boot_setup() -> Result<()> {
+	info!("Early boot setup");
+
+	// Basic hardware initialization
+	// This is done before memory allocators are available
+
+	Ok(())
+}
+
+/// Boot stage management
+static mut CURRENT_BOOT_STAGE: BootStage = BootStage::EarlyInit;
+
+/// Get current boot stage
+pub fn get_boot_stage() -> BootStage {
+	unsafe { CURRENT_BOOT_STAGE }
+}
+
+/// Set boot stage
+pub fn set_boot_stage(stage: BootStage) {
+	unsafe {
+		CURRENT_BOOT_STAGE = stage;
+	}
+	info!("Boot stage: {:?}", stage);
+}
+
+/// Complete boot process
+pub fn complete_boot() -> Result<()> {
+	set_boot_stage(BootStage::Complete);
+	info!("Boot process completed successfully");
+	Ok(())
+}
+
+/// Initialize multiboot information
+/// This should be called at the very beginning of kernel execution
+pub fn multiboot_init() {
+	// Parse multiboot information from bootloader
+	// For now, we'll use a combination of detection and defaults
+
+	let detected_memory = detect_memory_size();
+	let cpu_count = detect_cpu_count();
+
+	unsafe {
+		BOOT_INFO = BootInfo {
+			memory_size: detected_memory,
+			available_memory: (detected_memory * 95) / 100, // 95% available
+			cpu_count,
+			boot_time: read_tsc(),
+			command_line: None,
+			initrd_start: None,
+			initrd_size: None,
+			multiboot_addr: None,
+		};
+	}
+
+	info!("Multiboot information initialized");
+	info!("  Memory size: {} MB", detected_memory / (1024 * 1024));
+	info!(
+		"  Available memory: {} MB",
+		get_boot_info().available_memory / (1024 * 1024)
+	);
+	info!("  CPU count: {}", cpu_count);
+}
+
+/// Detect total system memory
+fn detect_memory_size() -> usize {
+	// Use CMOS to get basic memory information
+	unsafe {
+		// Read extended memory from CMOS (simplified)
+		crate::arch::x86_64::port::outb(0x70, 0x17);
+		let low = crate::arch::x86_64::port::inb(0x71) as usize;
+		crate::arch::x86_64::port::outb(0x70, 0x18);
+		let high = crate::arch::x86_64::port::inb(0x71) as usize;
+
+		let extended_mem = (high << 8) | low; // in KB
+		let total_mem = 1024 * 1024 + (extended_mem * 1024); // Base 1MB + extended
+
+		// Reasonable bounds checking
+		if total_mem < 16 * 1024 * 1024 {
+			// Default to 64MB if detection seems wrong
+			64 * 1024 * 1024
+		} else if total_mem > 8 * 1024 * 1024 * 1024 {
+			// Cap at 8GB for safety
+			8 * 1024 * 1024 * 1024
+		} else {
+			total_mem
+		}
+	}
+}
+
+/// Detect CPU count (simplified)
+fn detect_cpu_count() -> usize {
+	// For now, assume single CPU
+	// In a real implementation, this would parse ACPI tables or use CPUID
+	1
+}
+
+/// Read Time Stamp Counter
+fn read_tsc() -> u64 {
+	unsafe {
+		let low: u32;
+		let high: u32;
+		core::arch::asm!(
+		    "rdtsc",
+		    out("eax") low,
+		    out("edx") high,
+		    options(nomem, nostack, preserves_flags)
+		);
+		((high as u64) << 32) | (low as u64)
+	}
+}

kernel/src/console.rs

@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Console and kernel output
+
+use core::fmt::{self, Write};
+
+use crate::error::Result;
+use crate::sync::Spinlock;
+
+/// Console writer
+static CONSOLE: Spinlock<Console> = Spinlock::new(Console::new());
+
+/// VGA text mode colors
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u8)]
+pub enum Color {
+	Black = 0,
+	Blue = 1,
+	Green = 2,
+	Cyan = 3,
+	Red = 4,
+	Magenta = 5,
+	Brown = 6,
+	LightGray = 7,
+	DarkGray = 8,
+	LightBlue = 9,
+	LightGreen = 10,
+	LightCyan = 11,
+	LightRed = 12,
+	Pink = 13,
+	Yellow = 14,
+	White = 15,
+}
+
+/// VGA text mode color code combining foreground and background colors
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(transparent)]
+struct ColorCode(u8);
+
+impl ColorCode {
+	const fn new(foreground: Color, background: Color) -> ColorCode {
+		ColorCode((background as u8) << 4 | (foreground as u8))
+	}
+}
+
+/// VGA text mode screen character
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(C)]
+struct ScreenChar {
+	ascii_character: u8,
+	color_code: ColorCode,
+}
+
+/// VGA text mode buffer dimensions
+const BUFFER_HEIGHT: usize = 25;
+const BUFFER_WIDTH: usize = 80;
+
+/// VGA text mode buffer structure
+#[repr(transparent)]
+struct Buffer {
+	chars: [[ScreenChar; BUFFER_WIDTH]; BUFFER_HEIGHT],
+}
+
+struct Console {
+	initialized: bool,
+	vga_buffer: Option<&'static mut Buffer>,
+	column_position: usize,
+	color_code: ColorCode,
+}
+
+impl Console {
+	const fn new() -> Self {
+		Self {
+			initialized: false,
+			vga_buffer: None,
+			column_position: 0,
+			color_code: ColorCode::new(Color::Yellow, Color::Black),
+		}
+	}
+
+	fn init(&mut self) -> Result<()> {
+		// Initialize VGA text mode buffer
+		self.vga_buffer = Some(unsafe { &mut *(0xb8000 as *mut Buffer) });
+
+		// Initialize serial port (COM1)
+		self.init_serial();
+
+		self.clear_screen();
+		self.initialized = true;
+		Ok(())
+	}
+
+	fn init_serial(&self) {
+		unsafe {
+			// Disable interrupts
+			core::arch::asm!("out dx, al", in("dx") 0x3F9u16, in("al") 0x00u8);
+			// Set baud rate divisor
+			core::arch::asm!("out dx, al", in("dx") 0x3FBu16, in("al") 0x80u8); // Enable DLAB
+			core::arch::asm!("out dx, al", in("dx") 0x3F8u16, in("al") 0x03u8); // Divisor low byte (38400 baud)
+			core::arch::asm!("out dx, al", in("dx") 0x3F9u16, in("al") 0x00u8); // Divisor high byte
+								       // Configure line
+			core::arch::asm!("out dx, al", in("dx") 0x3FBu16, in("al") 0x03u8); // 8 bits, no parity, one stop bit
+			core::arch::asm!("out dx, al", in("dx") 0x3FCu16, in("al") 0xC7u8); // Enable FIFO, clear, 14-byte threshold
+			core::arch::asm!("out dx, al", in("dx") 0x3FEu16, in("al") 0x0Bu8); // IRQs enabled, RTS/DSR set
+		}
+	}
+
+	fn clear_screen(&mut self) {
+		if let Some(ref mut buffer) = self.vga_buffer {
+			let blank = ScreenChar {
+				ascii_character: b' ',
+				color_code: self.color_code,
+			};
+
+			for row in 0..BUFFER_HEIGHT {
+				for col in 0..BUFFER_WIDTH {
+					unsafe {
+						core::ptr::write_volatile(
+							&mut buffer.chars[row][col]
+								as *mut ScreenChar,
+							blank,
+						);
+					}
+				}
+			}
+		}
+		self.column_position = 0;
+	}
+
+	pub fn write_str(&mut self, s: &str) {
+		if !self.initialized {
+			return;
+		}
+
+		for byte in s.bytes() {
+			match byte {
+				b'\n' => self.new_line(),
+				byte => {
+					self.write_byte(byte);
+				}
+			}
+		}
+	}
+
+	fn write_byte(&mut self, byte: u8) {
+		// Write to serial port
+		self.write_serial(byte);
+
+		// Write to VGA buffer
+		match byte {
+			b'\n' => self.new_line(),
+			byte => {
+				if self.column_position >= BUFFER_WIDTH {
+					self.new_line();
+				}
+
+				if let Some(ref mut buffer) = self.vga_buffer {
+					let row = BUFFER_HEIGHT - 1;
+					let col = self.column_position;
+					let color_code = self.color_code;
+
+					unsafe {
+						core::ptr::write_volatile(
+							&mut buffer.chars[row][col]
+								as *mut ScreenChar,
+							ScreenChar {
+								ascii_character: byte,
+								color_code,
+							},
+						);
+					}
+				}
+				self.column_position += 1;
+			}
+		}
+	}
+
+	fn write_serial(&self, byte: u8) {
+		unsafe {
+			// Wait for transmit holding register to be empty
+			loop {
+				let mut status: u8;
+				core::arch::asm!("in al, dx", out("al") status, in("dx") 0x3FDu16);
+				if (status & 0x20) != 0 {
+					break;
+				}
+			}
+
+			// Write byte to serial port
+			core::arch::asm!(
+			    "out dx, al",
+			    in("dx") 0x3F8u16,
+			    in("al") byte,
+			);
+		}
+	}
+
+	fn new_line(&mut self) {
+		if let Some(ref mut buffer) = self.vga_buffer {
+			// Scroll up
+			for row in 1..BUFFER_HEIGHT {
+				for col in 0..BUFFER_WIDTH {
+					unsafe {
+						let character = core::ptr::read_volatile(
+							&buffer.chars[row][col]
+								as *const ScreenChar,
+						);
+						core::ptr::write_volatile(
+							&mut buffer.chars[row - 1][col]
+								as *mut ScreenChar,
+							character,
+						);
+					}
+				}
+			}
+
+			// Clear bottom row
+			let blank = ScreenChar {
+				ascii_character: b' ',
+				color_code: self.color_code,
+			};
+			for col in 0..BUFFER_WIDTH {
+				unsafe {
+					core::ptr::write_volatile(
+						&mut buffer.chars[BUFFER_HEIGHT - 1][col]
+							as *mut ScreenChar,
+						blank,
+					);
+				}
+			}
+		}
+		self.column_position = 0;
+	}
+}
+
+/// Initialize console
+pub fn init() -> Result<()> {
+	let mut console = CONSOLE.lock();
+	console.init()
+}
+
+/// Print function for kernel output
+pub fn _print(args: fmt::Arguments) {
+	let mut console = CONSOLE.lock();
+	let mut writer = ConsoleWriter(&mut *console);
+	writer.write_fmt(args).unwrap();
+}
+
+/// Print function for kernel messages with prefix
+pub fn _kprint(args: fmt::Arguments) {
+	let mut console = CONSOLE.lock();
+	let mut writer = ConsoleWriter(&mut *console);
+	writer.write_fmt(args).unwrap();
+}
+
+/// Print informational message
+pub fn print_info(message: &str) {
+	let mut console = CONSOLE.lock();
+	let mut writer = ConsoleWriter(&mut *console);
+	writer.write_str("[INFO] ").unwrap();
+	writer.write_str(message).unwrap();
+}
+
+/// Write string to console
+pub fn write_str(s: &str) {
+	let mut console = CONSOLE.lock();
+	console.write_str(s);
+}
+
+/// Clear the console screen
+pub fn clear() {
+	let mut console = CONSOLE.lock();
+	console.clear_screen();
+}
+
+struct ConsoleWriter<'a>(&'a mut Console);
+
+impl Write for ConsoleWriter<'_> {
+	fn write_str(&mut self, s: &str) -> fmt::Result {
+		self.0.write_str(s);
+		Ok(())
+	}
+}

kernel/src/cpu.rs

@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! CPU management
+use crate::error::Result;
+
+pub fn init() -> Result<()> {
+	Ok(())
+}

kernel/src/device.rs

@@ -0,0 +1,396 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Device management compatible with Linux kernel
+
+use alloc::{boxed::Box, collections::BTreeMap, string::String, vec::Vec};
+use core::any::Any;
+
+use crate::driver::Driver;
+use crate::error::{Error, Result};
+// Forward declarations for FileOperations trait
+use crate::fs::{File as VfsFile, Inode as VfsInode};
+use crate::memory::VmaArea;
+use crate::sync::Spinlock;
+
+/// Device number (major and minor) - Linux compatible
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct DeviceNumber {
+	pub major: u32,
+	pub minor: u32,
+}
+
+impl DeviceNumber {
+	/// Create a new device number
+	pub fn new(major: u32, minor: u32) -> Self {
+		Self { major, minor }
+	}
+
+	/// Convert to raw device number (Linux dev_t equivalent)
+	pub fn to_raw(&self) -> u64 {
+		((self.major as u64) << 32) | (self.minor as u64)
+	}
+
+	/// Alias for to_raw for compatibility
+	pub fn as_raw(&self) -> u64 {
+		self.to_raw()
+	}
+
+	/// Create from raw device number
+	pub fn from_raw(dev: u64) -> Self {
+		Self {
+			major: (dev >> 32) as u32,
+			minor: (dev & 0xFFFFFFFF) as u32,
+		}
+	}
+}
+
+/// Linux MKDEV macro equivalent
+pub fn mkdev(major: u32, minor: u32) -> DeviceNumber {
+	DeviceNumber::new(major, minor)
+}
+
+/// Device types - Linux compatible
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum DeviceType {
+	Character,
+	Block,
+	Network,
+	Input,
+	Sound,
+	Video,
+	Misc,
+	Platform,
+	Pci,
+	Usb,
+}
+
+/// Device structure - similar to Linux struct device
+#[derive(Debug)]
+pub struct Device {
+	pub name: String,
+	pub device_type: DeviceType,
+	pub major: u32,
+	pub minor: u32,
+	pub driver: Option<Box<dyn Driver>>,
+	pub parent: Option<String>,
+	pub private_data: Option<Box<dyn Any + Send + Sync>>,
+	pub power_state: PowerState,
+	pub dma_coherent: bool,
+	pub numa_node: i32,
+}
+
+/// Device power states
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum PowerState {
+	On,
+	Suspend,
+	Hibernate,
+	Off,
+}
+
+impl Device {
+	pub fn new(name: String, device_type: DeviceType, major: u32, minor: u32) -> Self {
+		Self {
+			name,
+			device_type,
+			major,
+			minor,
+			driver: None,
+			parent: None,
+			private_data: None,
+			power_state: PowerState::On,
+			dma_coherent: false,
+			numa_node: -1,
+		}
+	}
+
+	/// Set device driver
+	pub fn set_driver(&mut self, driver: Box<dyn Driver>) -> Result<()> {
+		// Probe the device with the driver
+		driver.probe(self)?;
+		self.driver = Some(driver);
+		Ok(())
+	}
+
+	/// Remove device driver
+	pub fn remove_driver(&mut self) -> Result<()> {
+		if let Some(driver) = self.driver.take() {
+			driver.remove(self)?;
+		}
+		Ok(())
+	}
+
+	/// Get device name
+	pub fn name(&self) -> &str {
+		&self.name
+	}
+
+	/// Check if device has driver
+	pub fn has_driver(&self) -> bool {
+		self.driver.is_some()
+	}
+
+	/// Set private data
+	pub fn set_private_data<T: Any + Send + Sync>(&mut self, data: T) {
+		self.private_data = Some(Box::new(data));
+	}
+
+	/// Get private data
+	pub fn get_private_data<T: Any + Send + Sync>(&self) -> Option<&T> {
+		self.private_data.as_ref()?.downcast_ref::<T>()
+	}
+	/// Power management
+	pub fn suspend(&mut self) -> Result<()> {
+		if let Some(driver) = &self.driver {
+			// We need to clone the driver to avoid borrowing issues
+			// In a real implementation, we'd use Rc/Arc or other shared ownership
+			// For now, we'll implement this differently
+			self.power_state = PowerState::Suspend;
+			// TODO: Call driver suspend when we have proper
+			// ownership model
+		}
+		Ok(())
+	}
+
+	pub fn resume(&mut self) -> Result<()> {
+		if let Some(driver) = &self.driver {
+			// We need to clone the driver to avoid borrowing issues
+			// In a real implementation, we'd use Rc/Arc or other shared ownership
+			// For now, we'll implement this differently
+			self.power_state = PowerState::On;
+			// TODO: Call driver resume when we have proper
+			// ownership model
+		}
+		Ok(())
+	}
+}
+
+/// Character device structure - Linux compatible
+#[derive(Debug)]
+pub struct CharDevice {
+	pub major: u32,
+	pub minor_start: u32,
+	pub minor_count: u32,
+	pub name: String,
+	pub fops: Option<Box<dyn FileOperations>>,
+}
+
+impl CharDevice {
+	pub fn new(major: u32, minor_start: u32, minor_count: u32, name: String) -> Self {
+		Self {
+			major,
+			minor_start,
+			minor_count,
+			name,
+			fops: None,
+		}
+	}
+}
+
+/// Block device structure - Linux compatible  
+#[derive(Debug)]
+pub struct BlockDevice {
+	pub major: u32,
+	pub minor: u32,
+	pub name: String,
+	pub size: u64, // Size in bytes
+	pub block_size: u32,
+}
+
+impl BlockDevice {
+	pub fn new(major: u32, minor: u32, name: String, size: u64, block_size: u32) -> Self {
+		Self {
+			major,
+			minor,
+			name,
+			size,
+			block_size,
+		}
+	}
+}
+
+/// File operations structure - Linux compatible
+pub trait FileOperations: Send + Sync + core::fmt::Debug {
+	fn open(&self, inode: &VfsInode, file: &mut VfsFile) -> Result<()>;
+	fn release(&self, inode: &VfsInode, file: &mut VfsFile) -> Result<()>;
+	fn read(&self, file: &mut VfsFile, buf: &mut [u8], offset: u64) -> Result<usize>;
+	fn write(&self, file: &mut VfsFile, buf: &[u8], offset: u64) -> Result<usize>;
+	fn ioctl(&self, file: &mut VfsFile, cmd: u32, arg: usize) -> Result<usize>;
+	fn mmap(&self, file: &mut VfsFile, vma: &mut VmaArea) -> Result<()>;
+}
+
+/// Re-exports for compatibility with driver.rs
+pub use crate::fs::{File, Inode};
+
+/// Global device subsystem
+static DEVICE_SUBSYSTEM: Spinlock<DeviceSubsystem> = Spinlock::new(DeviceSubsystem::new());
+
+/// Device subsystem state
+struct DeviceSubsystem {
+	devices: BTreeMap<String, Device>,
+	char_devices: BTreeMap<u32, CharDevice>, // major -> CharDevice
+	block_devices: BTreeMap<u32, BlockDevice>, // major -> BlockDevice
+	next_major: u32,
+}
+
+impl DeviceSubsystem {
+	const fn new() -> Self {
+		Self {
+			devices: BTreeMap::new(),
+			char_devices: BTreeMap::new(),
+			block_devices: BTreeMap::new(),
+			next_major: 240, // Start with dynamic major numbers
+		}
+	}
+
+	fn register_device(&mut self, device: Device) -> Result<()> {
+		let name = device.name.clone();
+		if self.devices.contains_key(&name) {
+			return Err(Error::Busy);
+		}
+		self.devices.insert(name, device);
+		Ok(())
+	}
+
+	fn unregister_device(&mut self, name: &str) -> Result<Device> {
+		self.devices.remove(name).ok_or(Error::NotFound)
+	}
+
+	#[allow(dead_code)]
+	fn find_device(&self, name: &str) -> Option<&Device> {
+		self.devices.get(name)
+	}
+
+	#[allow(dead_code)]
+	fn find_device_mut(&mut self, name: &str) -> Option<&mut Device> {
+		self.devices.get_mut(name)
+	}
+
+	fn allocate_major(&mut self) -> u32 {
+		let major = self.next_major;
+		self.next_major += 1;
+		major
+	}
+}
+
+/// Initialize device subsystem
+pub fn init() -> Result<()> {
+	let mut subsystem = DEVICE_SUBSYSTEM.lock();
+
+	// Register standard character devices
+	register_std_char_devices(&mut subsystem)?;
+
+	// Register standard block devices
+	register_std_block_devices(&mut subsystem)?;
+
+	crate::info!("Device subsystem initialized");
+	Ok(())
+}
+
+/// Register standard character devices
+fn register_std_char_devices(subsystem: &mut DeviceSubsystem) -> Result<()> {
+	// /dev/null (major 1, minor 3)
+	let null_dev = CharDevice::new(1, 3, 1, String::from("null"));
+	subsystem.char_devices.insert(1, null_dev);
+
+	// /dev/zero (major 1, minor 5)
+	let zero_dev = CharDevice::new(1, 5, 1, String::from("zero"));
+	// Note: This would overwrite the previous entry, so we need a better structure
+	// For now, simplified
+
+	// /dev/random (major 1, minor 8)
+	let random_dev = CharDevice::new(1, 8, 1, String::from("random"));
+
+	// /dev/urandom (major 1, minor 9)
+	let urandom_dev = CharDevice::new(1, 9, 1, String::from("urandom"));
+
+	Ok(())
+}
+
+/// Register standard block devices
+fn register_std_block_devices(subsystem: &mut DeviceSubsystem) -> Result<()> {
+	// RAM disk (major 1)
+	let ramdisk = BlockDevice::new(1, 0, String::from("ram0"), 16 * 1024 * 1024, 4096);
+	subsystem.block_devices.insert(1, ramdisk);
+
+	Ok(())
+}
+
+/// Register a device
+pub fn register_device(device: Device) -> Result<()> {
+	let mut subsystem = DEVICE_SUBSYSTEM.lock();
+	subsystem.register_device(device)
+}
+
+/// Unregister a device
+pub fn unregister_device(name: &str) -> Result<Device> {
+	let mut subsystem = DEVICE_SUBSYSTEM.lock();
+	subsystem.unregister_device(name)
+}
+
+/// Find a device by name
+pub fn find_device(name: &str) -> Option<&'static Device> {
+	// TODO: This is unsafe and needs proper lifetime management
+	// For now, we'll return None to avoid the Clone issue
+	None
+}
+
+/// Register a character device
+pub fn register_chrdev(major: u32, name: String, fops: Box<dyn FileOperations>) -> Result<u32> {
+	let mut subsystem = DEVICE_SUBSYSTEM.lock();
+
+	let actual_major = if major == 0 {
+		subsystem.allocate_major()
+	} else {
+		major
+	};
+
+	let mut char_dev = CharDevice::new(actual_major, 0, 256, name);
+	char_dev.fops = Some(fops);
+
+	if subsystem.char_devices.contains_key(&actual_major) {
+		return Err(Error::Busy);
+	}
+
+	subsystem.char_devices.insert(actual_major, char_dev);
+	Ok(actual_major)
+}
+
+/// Unregister a character device
+pub fn unregister_chrdev(major: u32) -> Result<()> {
+	let mut subsystem = DEVICE_SUBSYSTEM.lock();
+
+	if subsystem.char_devices.remove(&major).is_some() {
+		Ok(())
+	} else {
+		Err(Error::NotFound)
+	}
+}
+
+/// List all devices
+pub fn list_devices() -> Vec<String> {
+	let subsystem = DEVICE_SUBSYSTEM.lock();
+	subsystem.devices.keys().cloned().collect()
+}
+
+/// Device tree node - for device tree support
+#[derive(Debug)]
+pub struct DeviceTreeNode {
+	pub name: String,
+	pub compatible: Vec<String>,
+	pub reg: Vec<u64>,
+	pub interrupts: Vec<u32>,
+	pub properties: BTreeMap<String, Vec<u8>>,
+}
+
+impl DeviceTreeNode {
+	pub fn new(name: String) -> Self {
+		Self {
+			name,
+			compatible: Vec::new(),
+			reg: Vec::new(),
+			interrupts: Vec::new(),
+			properties: BTreeMap::new(),
+		}
+	}
+}

kernel/src/device_advanced.rs

@@ -0,0 +1,415 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Advanced device driver framework
+
+use alloc::{boxed::Box, collections::BTreeMap, string::String, vec::Vec};
+use core::fmt;
+
+use crate::error::{Error, Result};
+use crate::sync::Spinlock;
+use crate::types::DeviceId;
+
+/// Device class identifiers
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
+pub enum DeviceClass {
+	Block,
+	Character,
+	Network,
+	Storage,
+	Input,
+	Display,
+	Audio,
+	USB,
+	PCI,
+	Platform,
+	Virtual,
+}
+
+/// Device capabilities
+#[derive(Debug, Clone)]
+pub struct DeviceCapabilities {
+	pub can_read: bool,
+	pub can_write: bool,
+	pub can_seek: bool,
+	pub can_mmap: bool,
+	pub can_poll: bool,
+	pub is_removable: bool,
+	pub is_hotplug: bool,
+	pub supports_dma: bool,
+}
+
+impl Default for DeviceCapabilities {
+	fn default() -> Self {
+		Self {
+			can_read: true,
+			can_write: true,
+			can_seek: false,
+			can_mmap: false,
+			can_poll: false,
+			is_removable: false,
+			is_hotplug: false,
+			supports_dma: false,
+		}
+	}
+}
+
+/// Device power states
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum PowerState {
+	On,
+	Standby,
+	Suspend,
+	Off,
+}
+
+/// PCI device information
+#[derive(Debug, Clone)]
+pub struct PciDeviceInfo {
+	pub vendor_id: u16,
+	pub device_id: u16,
+	pub class_code: u8,
+	pub subclass: u8,
+	pub prog_if: u8,
+	pub revision: u8,
+	pub bus: u8,
+	pub device: u8,
+	pub function: u8,
+	pub base_addresses: [u32; 6],
+	pub irq: u8,
+}
+
+/// USB device information
+#[derive(Debug, Clone)]
+pub struct UsbDeviceInfo {
+	pub vendor_id: u16,
+	pub product_id: u16,
+	pub device_class: u8,
+	pub device_subclass: u8,
+	pub device_protocol: u8,
+	pub speed: UsbSpeed,
+	pub address: u8,
+	pub configuration: u8,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum UsbSpeed {
+	Low,       // 1.5 Mbps
+	Full,      // 12 Mbps
+	High,      // 480 Mbps
+	Super,     // 5 Gbps
+	SuperPlus, // 10 Gbps
+}
+
+/// Device tree information (for embedded systems)
+#[derive(Debug, Clone)]
+pub struct DeviceTreeInfo {
+	pub compatible: Vec<String>,
+	pub reg: Vec<u64>,
+	pub interrupts: Vec<u32>,
+	pub clocks: Vec<u32>,
+	pub properties: BTreeMap<String, String>,
+}
+
+/// Advanced device structure
+pub struct AdvancedDevice {
+	pub id: DeviceId,
+	pub name: String,
+	pub class: DeviceClass,
+	pub capabilities: DeviceCapabilities,
+	pub power_state: PowerState,
+	pub parent: Option<DeviceId>,
+	pub children: Vec<DeviceId>,
+
+	// Hardware-specific information
+	pub pci_info: Option<PciDeviceInfo>,
+	pub usb_info: Option<UsbDeviceInfo>,
+	pub dt_info: Option<DeviceTreeInfo>,
+
+	// Driver binding
+	pub driver: Option<Box<dyn AdvancedDeviceDriver>>,
+	pub driver_data: Option<Box<dyn core::any::Any + Send + Sync>>,
+
+	// Resource management
+	pub io_ports: Vec<(u16, u16)>,       // (start, size)
+	pub memory_regions: Vec<(u64, u64)>, // (base, size)
+	pub irq_lines: Vec<u32>,
+	pub dma_channels: Vec<u32>,
+
+	// Statistics
+	pub bytes_read: u64,
+	pub bytes_written: u64,
+	pub error_count: u64,
+	pub last_access: u64,
+}
+
+impl fmt::Debug for AdvancedDevice {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		f.debug_struct("AdvancedDevice")
+			.field("id", &self.id)
+			.field("name", &self.name)
+			.field("class", &self.class)
+			.field("capabilities", &self.capabilities)
+			.field("power_state", &self.power_state)
+			.field("parent", &self.parent)
+			.field("children", &self.children)
+			.finish()
+	}
+}
+
+impl AdvancedDevice {
+	pub fn new(id: DeviceId, name: String, class: DeviceClass) -> Self {
+		Self {
+			id,
+			name,
+			class,
+			capabilities: DeviceCapabilities::default(),
+			power_state: PowerState::Off,
+			parent: None,
+			children: Vec::new(),
+			pci_info: None,
+			usb_info: None,
+			dt_info: None,
+			driver: None,
+			driver_data: None,
+			io_ports: Vec::new(),
+			memory_regions: Vec::new(),
+			irq_lines: Vec::new(),
+			dma_channels: Vec::new(),
+			bytes_read: 0,
+			bytes_written: 0,
+			error_count: 0,
+			last_access: 0,
+		}
+	}
+
+	pub fn set_pci_info(&mut self, info: PciDeviceInfo) {
+		self.pci_info = Some(info);
+	}
+
+	pub fn set_usb_info(&mut self, info: UsbDeviceInfo) {
+		self.usb_info = Some(info);
+	}
+
+	pub fn add_io_port(&mut self, start: u16, size: u16) {
+		self.io_ports.push((start, size));
+	}
+
+	pub fn add_memory_region(&mut self, base: u64, size: u64) {
+		self.memory_regions.push((base, size));
+	}
+
+	pub fn add_irq(&mut self, irq: u32) {
+		self.irq_lines.push(irq);
+	}
+
+	pub fn set_power_state(&mut self, state: PowerState) -> Result<()> {
+		// Handle power state transitions
+		let result = match state {
+			PowerState::On => {
+				// Extract driver temporarily to avoid borrow conflicts
+				if let Some(mut driver) = self.driver.take() {
+					let result = driver.resume(self);
+					self.driver = Some(driver);
+					result
+				} else {
+					Ok(())
+				}
+			}
+			PowerState::Off => {
+				// Extract driver temporarily to avoid borrow conflicts
+				if let Some(mut driver) = self.driver.take() {
+					let result = driver.suspend(self);
+					self.driver = Some(driver);
+					result
+				} else {
+					Ok(())
+				}
+			}
+			_ => Ok(()),
+		};
+
+		if result.is_ok() {
+			self.power_state = state;
+		}
+		result
+	}
+
+	pub fn bind_driver(&mut self, driver: Box<dyn AdvancedDeviceDriver>) -> Result<()> {
+		if let Err(e) = driver.probe(self) {
+			return Err(e);
+		}
+		self.driver = Some(driver);
+		Ok(())
+	}
+
+	pub fn unbind_driver(&mut self) -> Result<()> {
+		if let Some(driver) = self.driver.take() {
+			driver.remove(self)?;
+		}
+		Ok(())
+	}
+}
+
+/// Advanced device driver trait
+pub trait AdvancedDeviceDriver: Send + Sync {
+	fn probe(&self, device: &mut AdvancedDevice) -> Result<()>;
+	fn remove(&self, device: &mut AdvancedDevice) -> Result<()>;
+	fn suspend(&self, device: &mut AdvancedDevice) -> Result<()>;
+	fn resume(&self, device: &mut AdvancedDevice) -> Result<()>;
+
+	// Optional methods
+	fn read(
+		&self,
+		_device: &mut AdvancedDevice,
+		_buf: &mut [u8],
+		_offset: u64,
+	) -> Result<usize> {
+		Err(Error::NotSupported)
+	}
+
+	fn write(&self, _device: &mut AdvancedDevice, _buf: &[u8], _offset: u64) -> Result<usize> {
+		Err(Error::NotSupported)
+	}
+
+	fn ioctl(&self, _device: &mut AdvancedDevice, _cmd: u32, _arg: usize) -> Result<usize> {
+		Err(Error::NotSupported)
+	}
+
+	fn interrupt_handler(&self, _device: &mut AdvancedDevice, _irq: u32) -> Result<()> {
+		Ok(())
+	}
+}
+
+/// Device registry for advanced devices
+pub struct AdvancedDeviceRegistry {
+	devices: BTreeMap<DeviceId, AdvancedDevice>,
+	next_id: u32,
+	drivers: Vec<Box<dyn AdvancedDeviceDriver>>,
+	device_classes: BTreeMap<DeviceClass, Vec<DeviceId>>,
+}
+
+impl AdvancedDeviceRegistry {
+	const fn new() -> Self {
+		Self {
+			devices: BTreeMap::new(),
+			next_id: 1,
+			drivers: Vec::new(),
+			device_classes: BTreeMap::new(),
+		}
+	}
+
+	pub fn register_device(&mut self, mut device: AdvancedDevice) -> Result<DeviceId> {
+		let id = DeviceId(self.next_id);
+		self.next_id += 1;
+		device.id = id;
+
+		// Try to bind a compatible driver
+		for driver in &self.drivers {
+			if device.driver.is_none() {
+				if let Ok(_) = driver.probe(&mut device) {
+					crate::info!("Driver bound to device {}", device.name);
+					break;
+				}
+			}
+		}
+
+		// Add to class index
+		self.device_classes
+			.entry(device.class)
+			.or_insert_with(Vec::new)
+			.push(id);
+
+		self.devices.insert(id, device);
+		Ok(id)
+	}
+
+	pub fn unregister_device(&mut self, id: DeviceId) -> Result<()> {
+		if let Some(mut device) = self.devices.remove(&id) {
+			device.unbind_driver()?;
+
+			// Remove from class index
+			if let Some(devices) = self.device_classes.get_mut(&device.class) {
+				devices.retain(|&x| x != id);
+			}
+		}
+		Ok(())
+	}
+
+	pub fn register_driver(&mut self, driver: Box<dyn AdvancedDeviceDriver>) {
+		// Try to bind to existing devices
+		for device in self.devices.values_mut() {
+			if device.driver.is_none() {
+				if let Ok(_) = driver.probe(device) {
+					crate::info!(
+						"Driver bound to existing device {}",
+						device.name
+					);
+				}
+			}
+		}
+
+		self.drivers.push(driver);
+	}
+
+	pub fn get_device(&self, id: DeviceId) -> Option<&AdvancedDevice> {
+		self.devices.get(&id)
+	}
+
+	pub fn get_device_mut(&mut self, id: DeviceId) -> Option<&mut AdvancedDevice> {
+		self.devices.get_mut(&id)
+	}
+
+	pub fn find_devices_by_class(&self, class: DeviceClass) -> Vec<DeviceId> {
+		self.device_classes.get(&class).cloned().unwrap_or_default()
+	}
+
+	pub fn find_devices_by_name(&self, name: &str) -> Vec<DeviceId> {
+		self.devices
+			.iter()
+			.filter(|(_, device)| device.name == name)
+			.map(|(&id, _)| id)
+			.collect()
+	}
+
+	pub fn get_device_statistics(&self) -> BTreeMap<DeviceClass, usize> {
+		let mut stats = BTreeMap::new();
+		for device in self.devices.values() {
+			*stats.entry(device.class).or_insert(0) += 1;
+		}
+		stats
+	}
+}
+
+/// Global advanced device registry
+pub static ADVANCED_DEVICE_REGISTRY: Spinlock<AdvancedDeviceRegistry> =
+	Spinlock::new(AdvancedDeviceRegistry::new());
+
+/// Initialize advanced device management
+pub fn init_advanced() -> Result<()> {
+	crate::info!("Advanced device management initialized");
+	Ok(())
+}
+
+/// Register a new advanced device
+pub fn register_advanced_device(device: AdvancedDevice) -> Result<DeviceId> {
+	let mut registry = ADVANCED_DEVICE_REGISTRY.lock();
+	registry.register_device(device)
+}
+
+/// Register a device driver
+pub fn register_device_driver(driver: Box<dyn AdvancedDeviceDriver>) {
+	let mut registry = ADVANCED_DEVICE_REGISTRY.lock();
+	registry.register_driver(driver);
+}
+
+/// Find devices by class
+pub fn find_devices_by_class(class: DeviceClass) -> Vec<DeviceId> {
+	let registry = ADVANCED_DEVICE_REGISTRY.lock();
+	registry.find_devices_by_class(class)
+}
+
+/// Get device statistics
+pub fn get_device_statistics() -> BTreeMap<DeviceClass, usize> {
+	let registry = ADVANCED_DEVICE_REGISTRY.lock();
+	registry.get_device_statistics()
+}

kernel/src/diagnostics.rs

@@ -0,0 +1,301 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel diagnostics and health monitoring
+
+use alloc::{format, string::String, vec::Vec};
+use core::fmt::Write;
+
+use crate::error::Result;
+use crate::sync::Spinlock;
+use crate::time::get_jiffies;
+use crate::types::Jiffies;
+
+/// System health status
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum HealthStatus {
+	Healthy,
+	Warning,
+	Critical,
+	Unknown,
+}
+
+/// Diagnostic category
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum DiagnosticCategory {
+	Memory,
+	CPU,
+	IO,
+	Network,
+	FileSystem,
+	Process,
+	Kernel,
+}
+
+/// Diagnostic entry
+#[derive(Debug, Clone)]
+pub struct DiagnosticEntry {
+	pub category: DiagnosticCategory,
+	pub status: HealthStatus,
+	pub message: String,
+	pub timestamp: Jiffies,
+	pub details: Option<String>,
+}
+
+/// System diagnostics
+pub struct SystemDiagnostics {
+	entries: Vec<DiagnosticEntry>,
+	last_check: Jiffies,
+	health_status: HealthStatus,
+}
+
+static DIAGNOSTICS: Spinlock<SystemDiagnostics> = Spinlock::new(SystemDiagnostics::new());
+
+impl SystemDiagnostics {
+	const fn new() -> Self {
+		Self {
+			entries: Vec::new(),
+			last_check: Jiffies(0),
+			health_status: HealthStatus::Unknown,
+		}
+	}
+
+	fn add_entry(&mut self, entry: DiagnosticEntry) {
+		// Keep only the last 1000 entries
+		if self.entries.len() >= 1000 {
+			self.entries.remove(0);
+		}
+
+		// Update overall health status
+		match entry.status {
+			HealthStatus::Critical => self.health_status = HealthStatus::Critical,
+			HealthStatus::Warning if self.health_status != HealthStatus::Critical => {
+				self.health_status = HealthStatus::Warning;
+			}
+			HealthStatus::Healthy if self.health_status == HealthStatus::Unknown => {
+				self.health_status = HealthStatus::Healthy;
+			}
+			_ => {}
+		}
+
+		self.entries.push(entry);
+	}
+
+	fn get_entries_by_category(&self, category: DiagnosticCategory) -> Vec<&DiagnosticEntry> {
+		self.entries
+			.iter()
+			.filter(|entry| entry.category == category)
+			.collect()
+	}
+
+	fn get_recent_entries(&self, max_age_jiffies: u64) -> Vec<&DiagnosticEntry> {
+		let current_time = get_jiffies();
+		self.entries
+			.iter()
+			.filter(|entry| {
+				(current_time - entry.timestamp).as_u64() <= max_age_jiffies
+			})
+			.collect()
+	}
+}
+
+/// Initialize diagnostics system
+pub fn init_diagnostics() -> Result<()> {
+	let mut diag = DIAGNOSTICS.lock();
+	diag.last_check = get_jiffies();
+	diag.health_status = HealthStatus::Healthy;
+
+	// Add initial diagnostic entry
+	let entry = DiagnosticEntry {
+		category: DiagnosticCategory::Kernel,
+		status: HealthStatus::Healthy,
+		message: "Diagnostics system initialized".into(),
+		timestamp: get_jiffies(),
+		details: None,
+	};
+	diag.add_entry(entry);
+
+	Ok(())
+}
+
+/// Add a diagnostic entry
+pub fn add_diagnostic(
+	category: DiagnosticCategory,
+	status: HealthStatus,
+	message: &str,
+	details: Option<&str>,
+) {
+	let mut diag = DIAGNOSTICS.lock();
+	let entry = DiagnosticEntry {
+		category,
+		status,
+		message: message.into(),
+		timestamp: get_jiffies(),
+		details: details.map(|s| s.into()),
+	};
+	diag.add_entry(entry);
+}
+
+/// Get system health status
+pub fn get_health_status() -> HealthStatus {
+	let diag = DIAGNOSTICS.lock();
+	diag.health_status
+}
+
+/// Run system health check
+pub fn run_health_check() -> Result<()> {
+	let mut issues_found = 0;
+
+	// Check memory usage
+	if let Ok(stats) = crate::memory::get_memory_stats() {
+		if stats.usage_percent > 90 {
+			add_diagnostic(
+				DiagnosticCategory::Memory,
+				HealthStatus::Critical,
+				"High memory usage",
+				Some(&format!("Memory usage: {}%", stats.usage_percent)),
+			);
+			issues_found += 1;
+		} else if stats.usage_percent > 75 {
+			add_diagnostic(
+				DiagnosticCategory::Memory,
+				HealthStatus::Warning,
+				"Elevated memory usage",
+				Some(&format!("Memory usage: {}%", stats.usage_percent)),
+			);
+		}
+	}
+
+	// Check kernel threads
+	if let Ok(thread_count) = crate::kthread::get_thread_count() {
+		if thread_count == 0 {
+			add_diagnostic(
+				DiagnosticCategory::Kernel,
+				HealthStatus::Warning,
+				"No kernel threads running",
+				None,
+			);
+		}
+	}
+
+	// Check file system
+	if let Ok(fs_stats) = crate::memfs::get_filesystem_stats() {
+		if fs_stats.files_count > 10000 {
+			add_diagnostic(
+				DiagnosticCategory::FileSystem,
+				HealthStatus::Warning,
+				"High number of files",
+				Some(&format!("Files: {}", fs_stats.files_count)),
+			);
+		}
+	}
+
+	// Update last check time
+	{
+		let mut diag = DIAGNOSTICS.lock();
+		diag.last_check = get_jiffies();
+	}
+
+	if issues_found == 0 {
+		add_diagnostic(
+			DiagnosticCategory::Kernel,
+			HealthStatus::Healthy,
+			"Health check completed - system healthy",
+			None,
+		);
+	}
+
+	Ok(())
+}
+
+/// Get diagnostic report
+pub fn get_diagnostic_report() -> String {
+	let diag = DIAGNOSTICS.lock();
+	let mut report = String::new();
+
+	writeln!(&mut report, "=== System Diagnostics Report ===").unwrap();
+	writeln!(&mut report, "Overall Health: {:?}", diag.health_status).unwrap();
+	writeln!(&mut report, "Last Check: {}", diag.last_check.as_u64()).unwrap();
+	writeln!(&mut report, "Total Entries: {}", diag.entries.len()).unwrap();
+	writeln!(&mut report).unwrap();
+
+	// Group by category
+	for category in [
+		DiagnosticCategory::Kernel,
+		DiagnosticCategory::Memory,
+		DiagnosticCategory::CPU,
+		DiagnosticCategory::IO,
+		DiagnosticCategory::Network,
+		DiagnosticCategory::FileSystem,
+		DiagnosticCategory::Process,
+	] {
+		let entries = diag.get_entries_by_category(category);
+		if !entries.is_empty() {
+			writeln!(&mut report, "{:?} ({} entries):", category, entries.len())
+				.unwrap();
+			for entry in entries.iter().rev().take(5) {
+				// Show last 5 entries
+				writeln!(
+					&mut report,
+					"  [{:?}] {} ({})",
+					entry.status,
+					entry.message,
+					entry.timestamp.as_u64()
+				)
+				.unwrap();
+				if let Some(details) = &entry.details {
+					writeln!(&mut report, "    Details: {}", details).unwrap();
+				}
+			}
+			writeln!(&mut report).unwrap();
+		}
+	}
+
+	report
+}
+
+/// Get recent critical issues
+pub fn get_critical_issues() -> Vec<DiagnosticEntry> {
+	let diag = DIAGNOSTICS.lock();
+	diag.entries
+		.iter()
+		.filter(|entry| entry.status == HealthStatus::Critical)
+		.rev()
+		.take(10)
+		.cloned()
+		.collect()
+}
+
+/// Clear diagnostic history
+pub fn clear_diagnostics() {
+	let mut diag = DIAGNOSTICS.lock();
+	diag.entries.clear();
+	diag.health_status = HealthStatus::Healthy;
+
+	// Add cleared entry
+	let entry = DiagnosticEntry {
+		category: DiagnosticCategory::Kernel,
+		status: HealthStatus::Healthy,
+		message: "Diagnostic history cleared".into(),
+		timestamp: get_jiffies(),
+		details: None,
+	};
+	diag.add_entry(entry);
+}
+
+/// Automatic health monitoring task
+pub fn health_monitor_task() {
+	loop {
+		// Run health check every 30 seconds (30000 jiffies at 1000 Hz)
+		if let Err(_) = run_health_check() {
+			add_diagnostic(
+				DiagnosticCategory::Kernel,
+				HealthStatus::Warning,
+				"Health check failed",
+				None,
+			);
+		}
+
+		// Sleep for 30 seconds
+		crate::kthread::sleep_for_jiffies(30000);
+	}
+}

kernel/src/driver.rs

@@ -0,0 +1,404 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Driver framework compatible with Linux kernel
+
+use alloc::{
+	boxed::Box,
+	collections::BTreeMap,
+	string::{String, ToString},
+	vec::Vec,
+};
+
+use crate::device::Device;
+use crate::error::{Error, Result};
+use crate::sync::Spinlock; // Add ToString
+
+/// Driver trait - Linux compatible
+pub trait Driver: Send + Sync + core::fmt::Debug {
+	/// Driver name
+	fn name(&self) -> &str;
+
+	/// Probe function - called when device is found
+	fn probe(&self, device: &mut Device) -> Result<()>;
+
+	/// Remove function - called when device is removed
+	fn remove(&self, device: &mut Device) -> Result<()>;
+
+	/// Suspend function - power management
+	fn suspend(&self, device: &mut Device) -> Result<()> {
+		// Default implementation does nothing
+		Ok(())
+	}
+
+	/// Resume function - power management
+	fn resume(&self, device: &mut Device) -> Result<()> {
+		// Default implementation does nothing
+		Ok(())
+	}
+
+	/// Shutdown function - system shutdown
+	fn shutdown(&self, device: &mut Device) {
+		// Default implementation does nothing
+	}
+}
+
+/// Driver operations for character devices
+pub trait CharDriverOps: Send + Sync {
+	fn open(&self, inode: &crate::device::Inode, file: &mut crate::device::File) -> Result<()>;
+	fn release(
+		&self,
+		inode: &crate::device::Inode,
+		file: &mut crate::device::File,
+	) -> Result<()>;
+	fn read(
+		&self,
+		file: &mut crate::device::File,
+		buf: &mut [u8],
+		offset: u64,
+	) -> Result<usize>;
+	fn write(&self, file: &mut crate::device::File, buf: &[u8], offset: u64) -> Result<usize>;
+	fn ioctl(&self, file: &mut crate::device::File, cmd: u32, arg: usize) -> Result<usize>;
+}
+
+/// Driver operations for block devices
+pub trait BlockDriverOps: Send + Sync {
+	fn read_block(&self, block: u64, buffer: &mut [u8]) -> Result<usize>;
+	fn write_block(&self, block: u64, buffer: &[u8]) -> Result<usize>;
+	fn get_block_size(&self) -> u32;
+	fn get_total_blocks(&self) -> u64;
+	fn flush(&self) -> Result<()>;
+}
+
+/// Platform driver - for platform devices
+pub trait PlatformDriver: Driver {
+	/// Match function - check if driver supports device
+	fn match_device(&self, device: &Device) -> bool;
+
+	/// Get supported device IDs
+	fn device_ids(&self) -> &[DeviceId];
+}
+
+/// Device ID structure - for driver matching
+#[derive(Debug, Clone)]
+pub struct DeviceId {
+	pub name: String,
+	pub vendor_id: Option<u32>,
+	pub device_id: Option<u32>,
+	pub class: Option<u32>,
+	pub compatible: Vec<String>, // Device tree compatible strings
+}
+
+impl DeviceId {
+	pub fn new(name: String) -> Self {
+		Self {
+			name,
+			vendor_id: None,
+			device_id: None,
+			class: None,
+			compatible: Vec::new(),
+		}
+	}
+
+	pub fn with_vendor_device(mut self, vendor_id: u32, device_id: u32) -> Self {
+		self.vendor_id = Some(vendor_id);
+		self.device_id = Some(device_id);
+		self
+	}
+
+	pub fn with_compatible(mut self, compatible: Vec<String>) -> Self {
+		self.compatible = compatible;
+		self
+	}
+}
+
+/// PCI driver - for PCI devices  
+pub trait PciDriver: Driver {
+	/// PCI device IDs supported by this driver
+	fn pci_ids(&self) -> &[PciDeviceId];
+
+	/// PCI-specific probe
+	fn pci_probe(&self, pci_dev: &mut PciDevice) -> Result<()>;
+
+	/// PCI-specific remove
+	fn pci_remove(&self, pci_dev: &mut PciDevice) -> Result<()>;
+}
+
+/// PCI device ID
+#[derive(Debug, Clone, Copy)]
+pub struct PciDeviceId {
+	pub vendor: u16,
+	pub device: u16,
+	pub subvendor: u16,
+	pub subdevice: u16,
+	pub class: u32,
+	pub class_mask: u32,
+}
+
+impl PciDeviceId {
+	pub const fn new(vendor: u16, device: u16) -> Self {
+		Self {
+			vendor,
+			device,
+			subvendor: 0xFFFF, // PCI_ANY_ID
+			subdevice: 0xFFFF,
+			class: 0,
+			class_mask: 0,
+		}
+	}
+}
+
+/// PCI device structure
+#[derive(Debug, Clone)]
+pub struct PciDevice {
+	pub vendor: u16,
+	pub device: u16,
+	pub subsystem_vendor: u16,
+	pub subsystem_device: u16,
+	pub class: u32,
+	pub revision: u8,
+	pub bus: u8,
+	pub slot: u8,
+	pub function: u8,
+	pub irq: u32,
+	pub bars: [PciBar; 6],
+}
+
+/// PCI Base Address Register
+#[derive(Debug, Clone, Copy)]
+pub struct PciBar {
+	pub address: u64,
+	pub size: u64,
+	pub flags: u32,
+}
+
+impl PciBar {
+	pub fn new() -> Self {
+		Self {
+			address: 0,
+			size: 0,
+			flags: 0,
+		}
+	}
+
+	pub fn is_io(&self) -> bool {
+		self.flags & 1 != 0
+	}
+
+	pub fn is_memory(&self) -> bool {
+		!self.is_io()
+	}
+
+	pub fn is_64bit(&self) -> bool {
+		self.is_memory() && (self.flags & 0x6) == 0x4
+	}
+}
+
+/// USB driver - for USB devices
+pub trait UsbDriver: Driver {
+	/// USB device IDs supported by this driver
+	fn usb_ids(&self) -> &[UsbDeviceId];
+
+	/// USB-specific probe
+	fn usb_probe(&self, usb_dev: &mut UsbDevice) -> Result<()>;
+
+	/// USB-specific disconnect
+	fn usb_disconnect(&self, usb_dev: &mut UsbDevice) -> Result<()>;
+}
+
+/// USB device ID
+#[derive(Debug, Clone, Copy)]
+pub struct UsbDeviceId {
+	pub vendor: u16,
+	pub product: u16,
+	pub device_class: u8,
+	pub device_subclass: u8,
+	pub device_protocol: u8,
+	pub interface_class: u8,
+	pub interface_subclass: u8,
+	pub interface_protocol: u8,
+}
+
+/// USB device structure
+#[derive(Debug)]
+pub struct UsbDevice {
+	pub vendor: u16,
+	pub product: u16,
+	pub device_class: u8,
+	pub device_subclass: u8,
+	pub device_protocol: u8,
+	pub speed: UsbSpeed,
+	pub address: u8,
+	pub configuration: u8,
+}
+
+/// USB speeds
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum UsbSpeed {
+	Low,       // 1.5 Mbps
+	Full,      // 12 Mbps
+	High,      // 480 Mbps
+	Super,     // 5 Gbps
+	SuperPlus, // 10 Gbps
+}
+
+/// Global driver subsystem
+static DRIVER_SUBSYSTEM: Spinlock<DriverSubsystem> = Spinlock::new(DriverSubsystem::new());
+
+/// Driver subsystem state
+struct DriverSubsystem {
+	drivers: BTreeMap<String, Box<dyn Driver>>,
+	platform_drivers: Vec<Box<dyn PlatformDriver>>,
+	pci_drivers: Vec<Box<dyn PciDriver>>,
+	usb_drivers: Vec<Box<dyn UsbDriver>>,
+}
+
+impl DriverSubsystem {
+	const fn new() -> Self {
+		Self {
+			drivers: BTreeMap::new(),
+			platform_drivers: Vec::new(),
+			pci_drivers: Vec::new(),
+			usb_drivers: Vec::new(),
+		}
+	}
+
+	fn register_driver(&mut self, driver: Box<dyn Driver>) -> Result<()> {
+		let name = driver.name().to_string();
+		if self.drivers.contains_key(&name) {
+			return Err(Error::Busy);
+		}
+		self.drivers.insert(name, driver);
+		Ok(())
+	}
+
+	fn unregister_driver(&mut self, name: &str) -> Result<()> {
+		if self.drivers.remove(name).is_some() {
+			Ok(())
+		} else {
+			Err(Error::NotFound)
+		}
+	}
+
+	#[allow(dead_code)]
+	fn find_driver(&self, name: &str) -> Option<&dyn Driver> {
+		self.drivers.get(name).map(|d| d.as_ref())
+	}
+}
+
+/// Register a driver
+pub fn register_driver(driver: Box<dyn Driver>) -> Result<()> {
+	let mut subsystem = DRIVER_SUBSYSTEM.lock();
+	let name = driver.name().to_string();
+	subsystem.register_driver(driver)?;
+	crate::info!("Registered driver: {}", name);
+	Ok(())
+}
+
+/// Unregister a driver
+pub fn unregister_driver(name: &str) -> Result<()> {
+	let mut subsystem = DRIVER_SUBSYSTEM.lock();
+	subsystem.unregister_driver(name)?;
+	crate::info!("Unregistered driver: {}", name);
+	Ok(())
+}
+
+/// Register a platform driver
+pub fn register_platform_driver(driver: Box<dyn PlatformDriver>) -> Result<()> {
+	let mut subsystem = DRIVER_SUBSYSTEM.lock();
+	let name = driver.name().to_string();
+
+	// Also register as a regular driver
+	let driver_copy = unsafe {
+		// This is a bit of a hack - we need to clone the driver
+		// In a real implementation, we'd use Arc or similar
+		core::mem::transmute::<*const dyn PlatformDriver, Box<dyn Driver>>(
+			driver.as_ref() as *const dyn PlatformDriver
+		)
+	};
+	subsystem.register_driver(driver_copy)?;
+	subsystem.platform_drivers.push(driver);
+
+	crate::info!("Registered platform driver: {}", name);
+	Ok(())
+}
+
+/// Register a PCI driver
+pub fn register_pci_driver(driver: Box<dyn PciDriver>) -> Result<()> {
+	let mut subsystem = DRIVER_SUBSYSTEM.lock();
+	let name = driver.name().to_string();
+	subsystem.pci_drivers.push(driver);
+	crate::info!("Registered PCI driver: {}", name);
+	Ok(())
+}
+
+/// Register a USB driver
+pub fn register_usb_driver(driver: Box<dyn UsbDriver>) -> Result<()> {
+	let mut subsystem = DRIVER_SUBSYSTEM.lock();
+	let name = driver.name().to_string();
+	subsystem.usb_drivers.push(driver);
+	crate::info!("Registered USB driver: {}", name);
+	Ok(())
+}
+
+/// Find and match a driver for a device
+pub fn match_driver(device: &Device) -> Option<String> {
+	let subsystem = DRIVER_SUBSYSTEM.lock();
+
+	// Try platform drivers first
+	for driver in &subsystem.platform_drivers {
+		if driver.match_device(device) {
+			return Some(driver.name().to_string());
+		}
+	}
+
+	// TODO: Try PCI, USB, etc. drivers based on device type
+
+	None
+}
+
+/// Get list of registered drivers
+pub fn list_drivers() -> Vec<String> {
+	let subsystem = DRIVER_SUBSYSTEM.lock();
+	subsystem.drivers.keys().cloned().collect()
+}
+
+/// Module macros for easier driver registration
+#[macro_export]
+macro_rules! platform_driver {
+	($driver:ident) => {
+		#[no_mangle]
+		pub extern "C" fn init_module() -> core::ffi::c_int {
+			match $crate::driver::register_platform_driver(Box::new($driver)) {
+				Ok(()) => 0,
+				Err(e) => e.to_errno(),
+			}
+		}
+
+		#[no_mangle]
+		pub extern "C" fn cleanup_module() {
+			$crate::driver::unregister_driver(stringify!($driver)).ok();
+		}
+	};
+}
+
+pub fn pci_config_read(bus: u8, device: u8, function: u8, offset: u8) -> u32 {
+	crate::hardware::pci_config_read(bus, device, function, offset)
+}
+
+#[macro_export]
+macro_rules! pci_driver {
+	($driver:ident) => {
+		#[no_mangle]
+		pub extern "C" fn init_module() -> core::ffi::c_int {
+			match $crate::driver::register_pci_driver(Box::new($driver)) {
+				Ok(()) => 0,
+				Err(e) => e.to_errno(),
+			}
+		}
+
+		#[no_mangle]
+		pub extern "C" fn cleanup_module() {
+			$crate::driver::unregister_driver(stringify!($driver)).ok();
+		}
+	};
+}

kernel/src/drivers_init.rs

@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Driver initialization and management
+
+use crate::error::Result;
+use crate::{info, warn};
+
+/// Initialize all built-in drivers
+pub fn init_drivers() -> Result<()> {
+	info!("Initializing built-in drivers");
+
+	// Initialize keyboard driver
+	init_keyboard_driver()?;
+
+	// Initialize serial driver
+	init_serial_driver()?;
+
+	// Initialize ramdisk driver
+	init_ramdisk_driver()?;
+
+	info!("Built-in drivers initialized");
+	Ok(())
+}
+
+/// Initialize PS/2 keyboard driver
+fn init_keyboard_driver() -> Result<()> {
+	info!("Initializing PS/2 keyboard driver");
+
+	// Register keyboard interrupt handler (IRQ 1)
+	if let Err(e) = crate::interrupt::request_irq(
+		1,
+		keyboard_interrupt_handler,
+		0,
+		"keyboard",
+		core::ptr::null_mut(),
+	) {
+		warn!("Failed to register keyboard interrupt: {}", e);
+		return Err(e);
+	}
+
+	info!("PS/2 keyboard driver initialized");
+	Ok(())
+}
+
+/// Initialize serial driver
+fn init_serial_driver() -> Result<()> {
+	info!("Initializing serial driver");
+
+	// Register serial interrupt handlers (IRQ 3 and 4)
+	if let Err(e) = crate::interrupt::request_irq(
+		3,
+		serial_interrupt_handler,
+		0,
+		"serial",
+		core::ptr::null_mut(),
+	) {
+		warn!("Failed to register serial interrupt: {}", e);
+	}
+
+	if let Err(e) = crate::interrupt::request_irq(
+		4,
+		serial_interrupt_handler,
+		0,
+		"serial",
+		core::ptr::null_mut(),
+	) {
+		warn!("Failed to register serial interrupt: {}", e);
+	}
+
+	info!("Serial driver initialized");
+	Ok(())
+}
+
+/// Initialize ramdisk driver
+fn init_ramdisk_driver() -> Result<()> {
+	info!("Initializing ramdisk driver");
+
+	// TODO: Create ramdisk device
+	// This would typically involve:
+	// 1. Allocating memory for the ramdisk
+	// 2. Registering the device with the block device subsystem
+	// 3. Setting up device file operations
+
+	info!("Ramdisk driver initialized");
+	Ok(())
+}
+
+/// Keyboard interrupt handler
+fn keyboard_interrupt_handler(irq: u32, dev_id: *mut u8) -> crate::interrupt::IrqReturn {
+	// Read the scan code from the keyboard controller
+	let scancode = unsafe { crate::arch::x86_64::port::inb(0x60) };
+
+	// Convert scan code to ASCII (simplified)
+	if scancode < 128 {
+		let ascii = SCANCODE_TO_ASCII[scancode as usize];
+		if ascii != 0 {
+			// Send character to kernel shell
+			if let Err(e) = crate::shell::shell_input(ascii as char) {
+				crate::warn!("Failed to process shell input: {}", e);
+			}
+		}
+	}
+
+	crate::interrupt::IrqReturn::Handled
+}
+
+/// Serial interrupt handler
+fn serial_interrupt_handler(irq: u32, dev_id: *mut u8) -> crate::interrupt::IrqReturn {
+	// TODO: Handle serial port interrupts
+	// This would typically involve reading from the serial port
+	// and handling incoming data
+
+	crate::interrupt::IrqReturn::Handled
+}
+
+/// Keyboard scan code to ASCII mapping (simplified US layout)
+const SCANCODE_TO_ASCII: [u8; 128] = [
+	0, 27, b'1', b'2', b'3', b'4', b'5', b'6', b'7', b'8', b'9', b'0', b'-', b'=',
+	8, // 0-14
+	b'\t', b'q', b'w', b'e', b'r', b't', b'y', b'u', b'i', b'o', b'p', b'[', b']',
+	b'\n', // 15-28
+	0,     // 29 ctrl
+	b'a', b's', b'd', b'f', b'g', b'h', b'j', b'k', b'l', b';', b'\'', b'`', // 30-41
+	0,    // 42 left shift
+	b'\\', b'z', b'x', b'c', b'v', b'b', b'n', b'm', b',', b'.', b'/', // 43-53
+	0,    // 54 right shift
+	b'*', 0,    // 55-56 alt
+	b' ', // 57 space
+	0,    // 58 caps lock
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 59-68 F1-F10
+	0, 0, // 69-70 num lock, scroll lock
+	b'7', b'8', b'9', b'-', b'4', b'5', b'6', b'+', b'1', b'2', b'3', b'0',
+	b'.', // 71-83 numpad
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 84-99
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 100-115
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 116-127
+];

kernel/src/enhanced_scheduler.rs

@@ -0,0 +1,567 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Enhanced preemptive scheduler with improved context switching
+
+use alloc::{
+	collections::{BTreeMap, VecDeque},
+	string::{String, ToString},
+	vec::Vec,
+};
+use core::sync::atomic::{AtomicBool, AtomicU64, Ordering};
+
+use crate::error::{Error, Result};
+use crate::sync::Spinlock;
+use crate::time::get_jiffies;
+use crate::types::{Jiffies, Tid};
+
+/// Preemption counter
+static PREEMPTION_COUNT: AtomicU64 = AtomicU64::new(0);
+
+/// Get preemption count
+pub fn get_preemption_count() -> u64 {
+	PREEMPTION_COUNT.load(Ordering::Relaxed)
+}
+
+/// Increment preemption counter
+pub fn increment_preemption_count() {
+	PREEMPTION_COUNT.fetch_add(1, Ordering::Relaxed);
+}
+
+/// Enhanced task state
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum TaskState {
+	Running,
+	Ready,
+	Blocked,
+	Sleeping,
+	Zombie,
+	Dead,
+}
+
+/// Task priority levels
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub enum Priority {
+	Critical = 0,
+	High = 1,
+	Normal = 2,
+	Low = 3,
+	Background = 4,
+}
+
+/// Enhanced task structure for better scheduling
+#[derive(Debug, Clone)]
+pub struct Task {
+	pub tid: Tid,
+	pub name: String,
+	pub state: TaskState,
+	pub priority: Priority,
+	pub vruntime: u64,                // Virtual runtime for fair scheduling
+	pub exec_time: u64,               // Total execution time
+	pub sleep_until: Option<Jiffies>, // Wake up time if sleeping
+	pub last_scheduled: Jiffies,      // Last time this task was scheduled
+	pub cpu_affinity: u32,            // CPU affinity mask
+	pub nice: i8,                     // Nice value (-20 to 19)
+	pub preempt_count: u32,           // Preemption counter
+}
+
+impl Task {
+	pub fn new(tid: Tid, name: String, priority: Priority) -> Self {
+		let now = get_jiffies();
+		Self {
+			tid,
+			name,
+			state: TaskState::Ready,
+			priority,
+			vruntime: 0,
+			exec_time: 0,
+			sleep_until: None,
+			last_scheduled: now,
+			cpu_affinity: 0xFFFFFFFF, // All CPUs by default
+			nice: 0,
+			preempt_count: 0,
+		}
+	}
+
+	/// Check if task is runnable
+	pub fn is_runnable(&self) -> bool {
+		match self.state {
+			TaskState::Ready | TaskState::Running => true,
+			TaskState::Sleeping => {
+				if let Some(wake_time) = self.sleep_until {
+					get_jiffies() >= wake_time
+				} else {
+					false
+				}
+			}
+			_ => false,
+		}
+	}
+
+	/// Update virtual runtime for fair scheduling
+	pub fn update_vruntime(&mut self, delta: u64) {
+		// Apply nice value weighting
+		let weight = nice_to_weight(self.nice);
+		self.vruntime += (delta * 1024) / weight;
+		self.exec_time += delta;
+	}
+
+	/// Wake up sleeping task
+	pub fn wake_up(&mut self) {
+		if self.state == TaskState::Sleeping {
+			self.state = TaskState::Ready;
+			self.sleep_until = None;
+		}
+	}
+}
+
+/// Convert nice value to weight for scheduling calculations
+fn nice_to_weight(nice: i8) -> u64 {
+	// Weight table based on nice values (exponential scale)
+	match nice {
+		-20..=-15 => 88761,
+		-14..=-10 => 71755,
+		-9..=-5 => 56483,
+		-4..=0 => 1024,
+		1..=5 => 820,
+		6..=10 => 655,
+		11..=15 => 526,
+		16..=19 => 423,
+		_ => 1024, // Default weight
+	}
+}
+
+/// Run queue for a specific priority level
+#[derive(Debug)]
+struct RunQueue {
+	tasks: VecDeque<Tid>,
+	total_weight: u64,
+	min_vruntime: u64,
+}
+
+impl RunQueue {
+	fn new() -> Self {
+		Self {
+			tasks: VecDeque::new(),
+			total_weight: 0,
+			min_vruntime: 0,
+		}
+	}
+
+	fn add_task(&mut self, tid: Tid) {
+		if !self.tasks.contains(&tid) {
+			self.tasks.push_back(tid);
+		}
+	}
+
+	fn remove_task(&mut self, tid: Tid) -> bool {
+		if let Some(pos) = self.tasks.iter().position(|&t| t == tid) {
+			self.tasks.remove(pos);
+			true
+		} else {
+			false
+		}
+	}
+
+	fn next_task(&mut self) -> Option<Tid> {
+		self.tasks.pop_front()
+	}
+
+	fn is_empty(&self) -> bool {
+		self.tasks.is_empty()
+	}
+}
+
+/// Enhanced scheduler with preemptive multitasking
+pub struct EnhancedScheduler {
+	tasks: BTreeMap<Tid, Task>,
+	run_queues: BTreeMap<Priority, RunQueue>,
+	current_task: Option<Tid>,
+	idle_task: Option<Tid>,
+	next_tid: AtomicU64,
+	total_context_switches: AtomicU64,
+	preemption_enabled: AtomicBool,
+	time_slice: u64, // Time slice in jiffies
+}
+
+impl EnhancedScheduler {
+	pub fn new() -> Self {
+		let mut run_queues = BTreeMap::new();
+		run_queues.insert(Priority::Critical, RunQueue::new());
+		run_queues.insert(Priority::High, RunQueue::new());
+		run_queues.insert(Priority::Normal, RunQueue::new());
+		run_queues.insert(Priority::Low, RunQueue::new());
+		run_queues.insert(Priority::Background, RunQueue::new());
+
+		Self {
+			tasks: BTreeMap::new(),
+			run_queues,
+			current_task: None,
+			idle_task: None,
+			next_tid: AtomicU64::new(1),
+			total_context_switches: AtomicU64::new(0),
+			preemption_enabled: AtomicBool::new(true),
+			time_slice: 10, // 10ms default time slice
+		}
+	}
+
+	/// Add a new task to the scheduler
+	pub fn add_task(&mut self, name: String, priority: Priority) -> Result<Tid> {
+		let tid = Tid(self.next_tid.fetch_add(1, Ordering::SeqCst) as u32);
+		let task = Task::new(tid, name, priority);
+
+		self.tasks.insert(tid, task);
+
+		if let Some(queue) = self.run_queues.get_mut(&priority) {
+			queue.add_task(tid);
+		}
+
+		Ok(tid)
+	}
+
+	/// Remove a task from the scheduler
+	pub fn remove_task(&mut self, tid: Tid) -> Result<()> {
+		if let Some(task) = self.tasks.remove(&tid) {
+			if let Some(queue) = self.run_queues.get_mut(&task.priority) {
+				queue.remove_task(tid);
+			}
+
+			if self.current_task == Some(tid) {
+				self.current_task = None;
+			}
+
+			Ok(())
+		} else {
+			Err(Error::NotFound)
+		}
+	}
+
+	/// Get the next task to run
+	pub fn schedule(&mut self) -> Option<Tid> {
+		// Check if current task can continue running
+		if let Some(current_tid) = self.current_task {
+			if let Some(current_task) = self.tasks.get(&current_tid) {
+				if current_task.is_runnable() && !self.should_preempt(current_task)
+				{
+					return Some(current_tid);
+				}
+			}
+		}
+
+		// Find the next task to run (priority-based with fair scheduling within
+		// priority)
+		for priority in [
+			Priority::Critical,
+			Priority::High,
+			Priority::Normal,
+			Priority::Low,
+			Priority::Background,
+		] {
+			if let Some(queue) = self.run_queues.get_mut(&priority) {
+				if !queue.is_empty() {
+					// For fair scheduling, pick task with lowest vruntime
+					let mut best_task = None;
+					let mut min_vruntime = u64::MAX;
+
+					for &tid in &queue.tasks {
+						if let Some(task) = self.tasks.get(&tid) {
+							if task.is_runnable()
+								&& task.vruntime < min_vruntime
+							{
+								min_vruntime = task.vruntime;
+								best_task = Some(tid);
+							}
+						}
+					}
+
+					if let Some(tid) = best_task {
+						// Remove from current position and add to back for
+						// round-robin
+						queue.remove_task(tid);
+						queue.add_task(tid);
+						return Some(tid);
+					}
+				}
+			}
+		}
+
+		// No runnable tasks, return idle task or None
+		self.idle_task
+	}
+
+	/// Check if current task should be preempted
+	fn should_preempt(&self, current_task: &Task) -> bool {
+		if !self.preemption_enabled.load(Ordering::SeqCst) {
+			return false;
+		}
+
+		let now = get_jiffies();
+		let time_running = now - current_task.last_scheduled;
+
+		// Preempt if time slice exceeded
+		if time_running.as_u64() > self.time_slice {
+			return true;
+		}
+
+		// Preempt if higher priority task is available
+		for priority in [Priority::Critical, Priority::High] {
+			if priority < current_task.priority {
+				if let Some(queue) = self.run_queues.get(&priority) {
+					if !queue.is_empty() {
+						return true;
+					}
+				}
+			}
+		}
+
+		false
+	}
+
+	/// Switch to a new task
+	pub fn switch_to(&mut self, tid: Tid) -> Result<()> {
+		if let Some(task) = self.tasks.get_mut(&tid) {
+			task.state = TaskState::Running;
+			task.last_scheduled = get_jiffies();
+			self.current_task = Some(tid);
+			self.total_context_switches.fetch_add(1, Ordering::SeqCst);
+			Ok(())
+		} else {
+			Err(Error::NotFound)
+		}
+	}
+
+	/// Put current task to sleep for specified duration
+	pub fn sleep(&mut self, duration_jiffies: u64) -> Result<()> {
+		if let Some(current_tid) = self.current_task {
+			if let Some(task) = self.tasks.get_mut(&current_tid) {
+				task.state = TaskState::Sleeping;
+				task.sleep_until = Some(get_jiffies() + duration_jiffies);
+				self.current_task = None;
+				Ok(())
+			} else {
+				Err(Error::NotFound)
+			}
+		} else {
+			Err(Error::InvalidArgument)
+		}
+	}
+
+	/// Wake up sleeping tasks
+	pub fn wake_up_sleepers(&mut self) {
+		let now = get_jiffies();
+
+		for task in self.tasks.values_mut() {
+			if task.state == TaskState::Sleeping {
+				if let Some(wake_time) = task.sleep_until {
+					if now >= wake_time {
+						task.wake_up();
+
+						// Add back to run queue
+						if let Some(queue) =
+							self.run_queues.get_mut(&task.priority)
+						{
+							queue.add_task(task.tid);
+						}
+					}
+				}
+			}
+		}
+	}
+
+	/// Update virtual runtime for current task
+	pub fn update_current_task(&mut self, time_delta: u64) {
+		if let Some(current_tid) = self.current_task {
+			if let Some(task) = self.tasks.get_mut(&current_tid) {
+				task.update_vruntime(time_delta);
+			}
+		}
+	}
+
+	/// Get scheduler statistics
+	pub fn get_stats(&self) -> SchedulerStats {
+		let total_tasks = self.tasks.len();
+		let runnable_tasks = self
+			.tasks
+			.values()
+			.filter(|task| task.is_runnable())
+			.count();
+		let sleeping_tasks = self
+			.tasks
+			.values()
+			.filter(|task| task.state == TaskState::Sleeping)
+			.count();
+
+		SchedulerStats {
+			total_tasks,
+			runnable_tasks,
+			sleeping_tasks,
+			context_switches: self.total_context_switches.load(Ordering::SeqCst),
+			preemption_enabled: self.preemption_enabled.load(Ordering::SeqCst),
+			current_task: self.current_task,
+		}
+	}
+
+	/// Enable/disable preemption
+	pub fn set_preemption(&self, enabled: bool) {
+		self.preemption_enabled.store(enabled, Ordering::SeqCst);
+	}
+
+	/// Get current task
+	pub fn current_task(&self) -> Option<Tid> {
+		self.current_task
+	}
+
+	/// Get task by ID
+	pub fn get_task(&self, tid: Tid) -> Option<&Task> {
+		self.tasks.get(&tid)
+	}
+
+	/// Set task priority
+	pub fn set_priority(&mut self, tid: Tid, priority: Priority) -> Result<()> {
+		if let Some(task) = self.tasks.get_mut(&tid) {
+			let old_priority = task.priority;
+			task.priority = priority;
+
+			// Move task between run queues
+			if let Some(old_queue) = self.run_queues.get_mut(&old_priority) {
+				old_queue.remove_task(tid);
+			}
+
+			if task.is_runnable() {
+				if let Some(new_queue) = self.run_queues.get_mut(&priority) {
+					new_queue.add_task(tid);
+				}
+			}
+
+			Ok(())
+		} else {
+			Err(Error::NotFound)
+		}
+	}
+
+	/// Create idle task
+	pub fn create_idle_task(&mut self) -> Result<Tid> {
+		let tid = self.add_task("idle".to_string(), Priority::Background)?;
+		self.idle_task = Some(tid);
+		Ok(tid)
+	}
+}
+
+/// Scheduler statistics
+#[derive(Debug, Clone)]
+pub struct SchedulerStats {
+	pub total_tasks: usize,
+	pub runnable_tasks: usize,
+	pub sleeping_tasks: usize,
+	pub context_switches: u64,
+	pub preemption_enabled: bool,
+	pub current_task: Option<Tid>,
+}
+
+/// Global enhanced scheduler
+static ENHANCED_SCHEDULER: Spinlock<Option<EnhancedScheduler>> = Spinlock::new(None);
+
+/// Helper to get scheduler reference safely
+fn with_scheduler<T, F>(f: F) -> Option<T>
+where
+	F: FnOnce(&mut EnhancedScheduler) -> T,
+{
+	let mut scheduler_option = ENHANCED_SCHEDULER.lock();
+	if let Some(ref mut scheduler) = *scheduler_option {
+		Some(f(scheduler))
+	} else {
+		None
+	}
+}
+
+/// Helper to get read-only scheduler reference safely
+fn with_scheduler_read<T, F>(f: F) -> Option<T>
+where
+	F: FnOnce(&EnhancedScheduler) -> T,
+{
+	let scheduler_option = ENHANCED_SCHEDULER.lock();
+	if let Some(ref scheduler) = *scheduler_option {
+		Some(f(scheduler))
+	} else {
+		None
+	}
+}
+
+/// Initialize enhanced scheduler
+pub fn init_enhanced_scheduler() -> Result<()> {
+	let mut scheduler_option = ENHANCED_SCHEDULER.lock();
+	if scheduler_option.is_none() {
+		let mut scheduler = EnhancedScheduler::new();
+		scheduler.create_idle_task()?;
+		*scheduler_option = Some(scheduler);
+	}
+	crate::info!("Enhanced scheduler initialized");
+	Ok(())
+}
+
+/// Schedule next task
+pub fn schedule_next() -> Option<Tid> {
+	with_scheduler(|scheduler| {
+		scheduler.wake_up_sleepers();
+		scheduler.schedule()
+	})
+	.flatten()
+}
+
+/// Add new task to scheduler
+pub fn add_task(name: String, priority: Priority) -> Result<Tid> {
+	with_scheduler(|scheduler| scheduler.add_task(name, priority))
+		.unwrap_or(Err(Error::NotInitialized))
+}
+
+/// Remove task from scheduler
+pub fn remove_task(tid: Tid) -> Result<()> {
+	with_scheduler(|scheduler| scheduler.remove_task(tid)).unwrap_or(Err(Error::NotInitialized))
+}
+
+/// Switch to specific task
+pub fn switch_to_task(tid: Tid) -> Result<()> {
+	with_scheduler(|scheduler| scheduler.switch_to(tid)).unwrap_or(Err(Error::NotInitialized))
+}
+
+/// Put current task to sleep
+pub fn sleep_current_task(duration_jiffies: u64) -> Result<()> {
+	with_scheduler(|scheduler| scheduler.sleep(duration_jiffies))
+		.unwrap_or(Err(Error::NotInitialized))
+}
+
+/// Get scheduler statistics
+pub fn get_scheduler_stats() -> SchedulerStats {
+	with_scheduler_read(|scheduler| scheduler.get_stats()).unwrap_or(SchedulerStats {
+		total_tasks: 0,
+		runnable_tasks: 0,
+		sleeping_tasks: 0,
+		context_switches: 0,
+		preemption_enabled: false,
+		current_task: None,
+	})
+}
+
+/// Update current task runtime
+pub fn update_current_task_runtime(time_delta: u64) {
+	with_scheduler(|scheduler| {
+		scheduler.update_current_task(time_delta);
+	});
+}
+
+/// Get current running task
+pub fn get_current_task() -> Option<Tid> {
+	with_scheduler_read(|scheduler| scheduler.current_task()).flatten()
+}
+
+/// Set task priority
+pub fn set_task_priority(tid: Tid, priority: Priority) -> Result<()> {
+	with_scheduler(|scheduler| scheduler.set_priority(tid, priority))
+		.unwrap_or(Err(Error::NotInitialized))
+}
+
+/// Enable or disable preemption
+pub fn set_preemption_enabled(enabled: bool) {
+	with_scheduler(|scheduler| {
+		scheduler.set_preemption(enabled);
+	});
+}

kernel/src/error.rs

@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Error handling types and utilities
+
+use core::fmt;
+
+/// Kernel error type
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Error {
+	/// Out of memory
+	OutOfMemory,
+	/// Invalid argument
+	InvalidArgument,
+	/// Permission denied
+	PermissionDenied,
+	/// Resource busy
+	Busy,
+	/// Resource busy (alias for IPC)
+	ResourceBusy,
+	/// Resource not found
+	NotFound,
+	/// Resource already exists
+	AlreadyExists,
+	/// Operation not supported
+	NotSupported,
+	/// I/O error
+	Io,
+	/// Generic I/O error (EIO)
+	EIO,
+	/// Interrupted operation
+	Interrupted,
+	/// Resource temporarily unavailable
+	WouldBlock,
+	/// Device error
+	Device,
+	/// Generic error
+	Generic,
+	/// Invalid operation
+	InvalidOperation,
+	/// Timeout
+	Timeout,
+	/// Not initialized
+	NotInitialized, // New error variant
+	/// Network unreachable
+	NetworkUnreachable,
+	/// Network is down
+	NetworkDown,
+	/// Device not found
+	DeviceNotFound,
+	/// Out of memory (ENOMEM)
+	ENOMEM,
+	/// Host unreachable (EHOSTUNREACH)
+	EHOSTUNREACH,
+
+	// Linux-compatible errno values
+	/// Operation not permitted (EPERM)
+	EPERM,
+	/// No such file or directory (ENOENT)
+	ENOENT,
+	/// Bad file descriptor (EBADF)
+	EBADF,
+	/// No such device (ENODEV)
+	ENODEV,
+	/// Invalid argument (EINVAL)
+	EINVAL,
+	/// No space left on device (ENOSPC)
+	ENOSPC,
+	/// Inappropriate ioctl for device (ENOTTY)
+	ENOTTY,
+	/// Illegal seek (ESPIPE)
+	ESPIPE,
+	/// No data available (ENODATA)
+	ENODATA,
+	/// Function not implemented (ENOSYS)
+	ENOSYS,
+	/// Not a directory (ENOTDIR)
+	ENOTDIR,
+	/// Is a directory (EISDIR)
+	EISDIR,
+	/// File exists (EEXIST)
+	EEXIST,
+	/// Directory not empty (ENOTEMPTY)
+	ENOTEMPTY,
+	/// No child process (ECHILD)
+	ECHILD,
+	/// No such process (ESRCH)
+	ESRCH,
+}
+
+impl Error {
+	/// Convert error to errno value
+	pub fn to_errno(self) -> i32 {
+		match self {
+			Error::OutOfMemory => -12,     // ENOMEM
+			Error::InvalidArgument => -22, // EINVAL
+			Error::PermissionDenied => -1, // EPERM
+			Error::Busy => -16,            // EBUSY
+			Error::ResourceBusy => -16,    // EBUSY (alias)
+			Error::NotFound => -2,         // ENOENT
+			Error::AlreadyExists => -17,   // EEXIST
+			Error::NotSupported => -38,    // ENOSYS
+			Error::Io => -5,               // EIO
+			Error::Interrupted => -4,      // EINTR
+			Error::WouldBlock => -11,      // EAGAIN
+			Error::Device => -19,          // ENODEV
+			Error::Generic => -1,          // EPERM
+			Error::InvalidOperation => -1, // EPERM
+			Error::Timeout => -110,        // ETIMEDOUT
+			Error::NotInitialized => -6,   // ENXIO
+
+			// Linux errno mappings
+			Error::EPERM => -1,                // EPERM
+			Error::ENOENT => -2,               // ENOENT
+			Error::EBADF => -9,                // EBADF
+			Error::ENODEV => -19,              // ENODEV
+			Error::EINVAL => -22,              // EINVAL
+			Error::ENOSPC => -28,              // ENOSPC
+			Error::ENOTTY => -25,              // ENOTTY
+			Error::ESPIPE => -29,              // ESPIPE
+			Error::ENODATA => -61,             // ENODATA
+			Error::ENOSYS => -38,              // ENOSYS
+			Error::ENOTDIR => -20,             // ENOTDIR
+			Error::EISDIR => -21,              // EISDIR
+			Error::EEXIST => -17,              // EEXIST
+			Error::ENOTEMPTY => -39,           // ENOTEMPTY
+			Error::ECHILD => -10,              // ECHILD
+			Error::ESRCH => -3,                // ESRCH
+			Error::NetworkUnreachable => -101, // ENETUNREACH
+			Error::NetworkDown => -100,        // ENETDOWN
+			Error::DeviceNotFound => -19,      // ENODEV
+			Error::ENOMEM => -12,              // ENOMEM
+			Error::EHOSTUNREACH => -113,       // EHOSTUNREACH
+			Error::EIO => -5,                  // EIO
+		}
+	}
+}
+
+impl fmt::Display for Error {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		match self {
+			Error::OutOfMemory => write!(f, "Out of memory"),
+			Error::InvalidArgument => write!(f, "Invalid argument"),
+			Error::PermissionDenied => write!(f, "Permission denied"),
+			Error::Busy => write!(f, "Resource busy"),
+			Error::ResourceBusy => write!(f, "Resource busy"),
+			Error::NotFound => write!(f, "Resource not found"),
+			Error::AlreadyExists => write!(f, "Resource already exists"),
+			Error::NotSupported => write!(f, "Operation not supported"),
+			Error::Io => write!(f, "I/O error"),
+			Error::Interrupted => write!(f, "Interrupted operation"),
+			Error::WouldBlock => write!(f, "Resource temporarily unavailable"),
+			Error::Device => write!(f, "Device error"),
+			Error::Generic => write!(f, "Generic error"),
+			Error::InvalidOperation => write!(f, "Invalid operation"),
+			Error::Timeout => write!(f, "Operation timed out"),
+			Error::NotInitialized => write!(f, "Not initialized"),
+			Error::NetworkUnreachable => write!(f, "Network unreachable"),
+			Error::NetworkDown => write!(f, "Network is down"),
+			Error::DeviceNotFound => write!(f, "Device not found"),
+			Error::ENOMEM => write!(f, "Out of memory"),
+			Error::EHOSTUNREACH => write!(f, "Host unreachable"),
+
+			// Linux errno variants
+			Error::EPERM => write!(f, "Operation not permitted"),
+			Error::ENOENT => write!(f, "No such file or directory"),
+			Error::EBADF => write!(f, "Bad file descriptor"),
+			Error::ENODEV => write!(f, "No such device"),
+			Error::EINVAL => write!(f, "Invalid argument"),
+			Error::ENOSPC => write!(f, "No space left on device"),
+			Error::ENOTTY => write!(f, "Inappropriate ioctl for device"),
+			Error::ESPIPE => write!(f, "Illegal seek"),
+			Error::ENODATA => write!(f, "No data available"),
+			Error::ENOSYS => write!(f, "Function not implemented"),
+			Error::ENOTDIR => write!(f, "Not a directory"),
+			Error::EISDIR => write!(f, "Is a directory"),
+			Error::EEXIST => write!(f, "File exists"),
+			Error::ENOTEMPTY => write!(f, "Directory not empty"),
+			Error::ECHILD => write!(f, "No child processes"),
+			Error::ESRCH => write!(f, "No such process"),
+			Error::EIO => write!(f, "Input/output error"),
+		}
+	}
+}
+
+/// Kernel result type
+pub type Result<T> = core::result::Result<T, Error>;
+
+/// Convert from various error types
+impl From<()> for Error {
+	fn from(_: ()) -> Self {
+		Error::Generic
+	}
+}
+
+impl From<core::alloc::AllocError> for Error {
+	fn from(_: core::alloc::AllocError) -> Self {
+		Error::OutOfMemory
+	}
+}

kernel/src/fs/advanced.rs

@@ -0,0 +1,312 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Advanced file system operations and utilities
+
+use crate::error::{Error, Result};
+use crate::fs::file::File;
+use crate::fs::inode::Inode;
+use crate::fs::dentry::Dentry;
+use alloc::string::String;
+use alloc::vec::Vec;
+use spin::Mutex;
+use alloc::sync::Arc;
+
+/// File system statistics
+#[derive(Debug, Clone)]
+pub struct FsStats {
+    pub total_inodes: u64,
+    pub free_inodes: u64,
+    pub total_blocks: u64,
+    pub free_blocks: u64,
+    pub block_size: u32,
+    pub max_filename_len: u32,
+    pub filesystem_type: String,
+}
+
+/// Directory entry information
+#[derive(Debug, Clone)]
+pub struct DirEntry {
+    pub name: String,
+    pub inode_number: u64,
+    pub file_type: u8,
+}
+
+/// File system operations
+pub struct AdvancedFsOps;
+
+impl AdvancedFsOps {
+    /// Create a new file with specified permissions
+    pub fn create_file(path: &str, mode: u32) -> Result<Arc<File>> {
+        crate::info!("Creating file: {} with mode: {:o}", path, mode);
+        
+        // Parse path and get parent directory
+        let (parent_path, filename) = split_path(path)?;
+        
+        // Get parent directory inode
+        let parent_inode = crate::fs::path::path_lookup(parent_path)?;
+        
+        // Create new inode for file
+        let new_inode = crate::fs::inode::alloc_inode()?;
+        new_inode.set_mode(mode | crate::fs::mode::S_IFREG);
+        new_inode.set_size(0);
+        
+        // Create dentry
+        let dentry = Arc::new(Dentry::new(filename.to_string(), new_inode.clone()));
+        
+        // Add to parent directory
+        parent_inode.add_child(dentry)?;
+        
+        // Create file handle
+        let file = Arc::new(File::new(new_inode, crate::fs::file::O_RDWR));
+        
+        Ok(file)
+    }
+    
+    /// Create a new directory
+    pub fn create_directory(path: &str, mode: u32) -> Result<()> {
+        crate::info!("Creating directory: {} with mode: {:o}", path, mode);
+        
+        let (parent_path, dirname) = split_path(path)?;
+        let parent_inode = crate::fs::path::path_lookup(parent_path)?;
+        
+        // Create new inode for directory
+        let new_inode = crate::fs::inode::alloc_inode()?;
+        new_inode.set_mode(mode | crate::fs::mode::S_IFDIR);
+        new_inode.set_size(0);
+        
+        // Create dentry
+        let dentry = Arc::new(Dentry::new(dirname.to_string(), new_inode.clone()));
+        
+        // Add to parent directory
+        parent_inode.add_child(dentry)?;
+        
+        Ok(())
+    }
+    
+    /// Remove a file or directory
+    pub fn remove_path(path: &str) -> Result<()> {
+        crate::info!("Removing path: {}", path);
+        
+        let (parent_path, filename) = split_path(path)?;
+        let parent_inode = crate::fs::path::path_lookup(parent_path)?;
+        
+        // Find and remove the child
+        parent_inode.remove_child(filename)?;
+        
+        Ok(())
+    }
+    
+    /// List directory contents
+    pub fn list_directory(path: &str) -> Result<Vec<DirEntry>> {
+        let inode = crate::fs::path::path_lookup(path)?;
+        
+        if !inode.is_dir() {
+            return Err(Error::ENOTDIR);
+        }
+        
+        let mut entries = Vec::new();
+        
+        // Add . and .. entries
+        entries.push(DirEntry {
+            name: ".".to_string(),
+            inode_number: inode.get_ino(),
+            file_type: crate::fs::mode::DT_DIR,
+        });
+        
+        if let Some(parent) = inode.get_parent() {
+            entries.push(DirEntry {
+                name: "..".to_string(),
+                inode_number: parent.get_ino(),
+                file_type: crate::fs::mode::DT_DIR,
+            });
+        }
+        
+        // Add actual directory entries
+        for child in inode.get_children() {
+            let file_type = if child.inode.is_dir() {
+                crate::fs::mode::DT_DIR
+            } else {
+                crate::fs::mode::DT_REG
+            };
+            
+            entries.push(DirEntry {
+                name: child.name.clone(),
+                inode_number: child.inode.get_ino(),
+                file_type,
+            });
+        }
+        
+        Ok(entries)
+    }
+    
+    /// Get file/directory statistics
+    pub fn get_stats(path: &str) -> Result<crate::fs::inode::Stat> {
+        let inode = crate::fs::path::path_lookup(path)?;
+        Ok(inode.get_stat())
+    }
+    
+    /// Get file system statistics
+    pub fn get_fs_stats(path: &str) -> Result<FsStats> {
+        let _inode = crate::fs::path::path_lookup(path)?;
+        
+        // Return simplified stats
+        Ok(FsStats {
+            total_inodes: 1000000,
+            free_inodes: 999000,
+            total_blocks: 1000000,
+            free_blocks: 900000,
+            block_size: 4096,
+            max_filename_len: 255,
+            filesystem_type: "RustFS".to_string(),
+        })
+    }
+    
+    /// Copy file
+    pub fn copy_file(src: &str, dst: &str) -> Result<()> {
+        crate::info!("Copying file from {} to {}", src, dst);
+        
+        // Open source file
+        let src_inode = crate::fs::path::path_lookup(src)?;
+        if src_inode.is_dir() {
+            return Err(Error::EISDIR);
+        }
+        
+        // Read source file data
+        let mut buffer = vec![0u8; src_inode.get_size() as usize];
+        src_inode.read_at(0, &mut buffer)?;
+        
+        // Create destination file
+        let dst_file = Self::create_file(dst, 0o644)?;
+        
+        // Write data to destination
+        dst_file.write(&buffer)?;
+        
+        Ok(())
+    }
+    
+    /// Move/rename file
+    pub fn move_file(src: &str, dst: &str) -> Result<()> {
+        crate::info!("Moving file from {} to {}", src, dst);
+        
+        // Copy file
+        Self::copy_file(src, dst)?;
+        
+        // Remove source
+        Self::remove_path(src)?;
+        
+        Ok(())
+    }
+    
+    /// Create symbolic link
+    pub fn create_symlink(target: &str, link: &str) -> Result<()> {
+        crate::info!("Creating symlink: {} -> {}", link, target);
+        
+        let (parent_path, linkname) = split_path(link)?;
+        let parent_inode = crate::fs::path::path_lookup(parent_path)?;
+        
+        // Create new inode for symlink
+        let new_inode = crate::fs::inode::alloc_inode()?;
+        new_inode.set_mode(0o777 | crate::fs::mode::S_IFLNK);
+        new_inode.set_size(target.len() as u64);
+        
+        // Store target path in inode data
+        new_inode.write_at(0, target.as_bytes())?;
+        
+        // Create dentry
+        let dentry = Arc::new(Dentry::new(linkname.to_string(), new_inode.clone()));
+        
+        // Add to parent directory
+        parent_inode.add_child(dentry)?;
+        
+        Ok(())
+    }
+    
+    /// Create hard link
+    pub fn create_hardlink(target: &str, link: &str) -> Result<()> {
+        crate::info!("Creating hardlink: {} -> {}", link, target);
+        
+        let target_inode = crate::fs::path::path_lookup(target)?;
+        let (parent_path, linkname) = split_path(link)?;
+        let parent_inode = crate::fs::path::path_lookup(parent_path)?;
+        
+        // Create dentry pointing to existing inode
+        let dentry = Arc::new(Dentry::new(linkname.to_string(), target_inode.clone()));
+        
+        // Add to parent directory
+        parent_inode.add_child(dentry)?;
+        
+        // Increment link count
+        target_inode.inc_nlink();
+        
+        Ok(())
+    }
+}
+
+/// Split path into parent and filename
+fn split_path(path: &str) -> Result<(&str, &str)> {
+    if path == "/" {
+        return Err(Error::EINVAL);
+    }
+    
+    let path = path.trim_end_matches('/');
+    if let Some(pos) = path.rfind('/') {
+        let parent = if pos == 0 { "/" } else { &path[..pos] };
+        let filename = &path[pos + 1..];
+        Ok((parent, filename))
+    } else {
+        Ok(("/", path))
+    }
+}
+
+/// File system utility functions
+pub mod utils {
+    use super::*;
+    
+    /// Check if path exists
+    pub fn path_exists(path: &str) -> bool {
+        crate::fs::path::path_lookup(path).is_ok()
+    }
+    
+    /// Check if path is a directory
+    pub fn is_directory(path: &str) -> bool {
+        if let Ok(inode) = crate::fs::path::path_lookup(path) {
+            inode.is_dir()
+        } else {
+            false
+        }
+    }
+    
+    /// Check if path is a regular file
+    pub fn is_regular_file(path: &str) -> bool {
+        if let Ok(inode) = crate::fs::path::path_lookup(path) {
+            inode.is_file()
+        } else {
+            false
+        }
+    }
+    
+    /// Get file size
+    pub fn get_file_size(path: &str) -> Result<u64> {
+        let inode = crate::fs::path::path_lookup(path)?;
+        Ok(inode.get_size())
+    }
+    
+    /// Get file permissions
+    pub fn get_file_mode(path: &str) -> Result<u32> {
+        let inode = crate::fs::path::path_lookup(path)?;
+        Ok(inode.get_mode())
+    }
+    
+    /// Set file permissions
+    pub fn set_file_mode(path: &str, mode: u32) -> Result<()> {
+        let inode = crate::fs::path::path_lookup(path)?;
+        inode.set_mode(mode);
+        Ok(())
+    }
+}
+
+/// Initialize advanced file system operations
+pub fn init() -> Result<()> {
+    crate::info!("Advanced file system operations initialized");
+    Ok(())
+}

kernel/src/fs/dentry.rs

@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Directory entry (dentry) abstraction - Linux compatible
+
+use alloc::{format, string::String, vec::Vec}; // Add format macro
+use core::sync::atomic::{AtomicU32, Ordering};
+
+use crate::error::Result;
+use crate::sync::{Arc, Mutex};
+
+/// Dentry structure - similar to Linux struct dentry
+#[derive(Debug)]
+pub struct Dentry {
+	/// Entry name
+	pub d_name: String,
+	/// Associated inode
+	pub d_inode: Option<Arc<super::Inode>>,
+	/// Parent dentry
+	pub d_parent: Option<Arc<Dentry>>,
+	/// Child entries (for directories)
+	pub d_subdirs: Mutex<Vec<Arc<Dentry>>>,
+	/// Dentry operations
+	pub d_op: Option<Arc<dyn DentryOperations>>,
+	/// Superblock
+	pub d_sb: Option<Arc<super::SuperBlock>>,
+	/// Reference count
+	pub d_count: AtomicU32,
+	/// Dentry flags
+	pub d_flags: AtomicU32,
+	/// Hash for dcache
+	pub d_hash: u32,
+}
+
+impl Dentry {
+	/// Create a new dentry
+	pub fn new(name: String, inode: Option<Arc<super::Inode>>) -> Self {
+		Self {
+			d_name: name,
+			d_inode: inode,
+			d_parent: None,
+			d_subdirs: Mutex::new(Vec::new()),
+			d_op: None,
+			d_sb: None,
+			d_count: AtomicU32::new(1),
+			d_flags: AtomicU32::new(0),
+			d_hash: 0, // TODO: Calculate hash
+		}
+	}
+
+	/// Set parent dentry
+	pub fn set_parent(&mut self, parent: Arc<Dentry>) {
+		self.d_parent = Some(parent);
+	}
+
+	/// Add child dentry
+	pub fn add_child(&self, child: Arc<Dentry>) {
+		let mut subdirs = self.d_subdirs.lock();
+		subdirs.push(child);
+	}
+
+	/// Find child dentry by name
+	pub fn find_child(&self, name: &str) -> Option<Arc<Dentry>> {
+		let subdirs = self.d_subdirs.lock();
+		for child in subdirs.iter() {
+			if child.d_name == name {
+				return Some(child.clone());
+			}
+		}
+		None
+	}
+
+	/// Get full path of this dentry
+	pub fn get_path(&self) -> String {
+		if let Some(ref parent) = self.d_parent {
+			if parent.d_name == "/" {
+				format!("/{}", self.d_name)
+			} else {
+				format!("{}/{}", parent.get_path(), self.d_name)
+			}
+		} else {
+			self.d_name.clone()
+		}
+	}
+
+	/// Check if dentry is root
+	pub fn is_root(&self) -> bool {
+		self.d_parent.is_none() || self.d_name == "/"
+	}
+
+	/// Increment reference count
+	pub fn dget(&self) {
+		self.d_count.fetch_add(1, Ordering::Relaxed);
+	}
+
+	/// Decrement reference count
+	pub fn dput(&self) {
+		let old_count = self.d_count.fetch_sub(1, Ordering::Relaxed);
+		if old_count == 1 {
+			// Last reference, dentry should be cleaned up
+			// TODO: Call d_delete operation if present
+		}
+	}
+
+	/// Revalidate dentry
+	pub fn revalidate(&self) -> Result<bool> {
+		if let Some(ref ops) = self.d_op {
+			ops.revalidate(self)
+		} else {
+			Ok(true) // Always valid by default
+		}
+	}
+
+	/// Delete dentry
+	pub fn delete(&self) -> Result<()> {
+		if let Some(ref ops) = self.d_op {
+			ops.delete(self)
+		} else {
+			Ok(())
+		}
+	}
+
+	/// Compare two dentries
+	pub fn compare(&self, other: &Dentry) -> Result<bool> {
+		if let Some(ref ops) = self.d_op {
+			ops.compare(self, other)
+		} else {
+			Ok(self.d_name == other.d_name)
+		}
+	}
+
+	/// Hash dentry name
+	pub fn hash(&self) -> Result<u32> {
+		if let Some(ref ops) = self.d_op {
+			ops.hash(self)
+		} else {
+			// Simple hash function
+			let mut hash = 0u32;
+			for byte in self.d_name.bytes() {
+				hash = hash.wrapping_mul(31).wrapping_add(byte as u32);
+			}
+			Ok(hash)
+		}
+	}
+}
+
+unsafe impl Send for Dentry {}
+unsafe impl Sync for Dentry {}
+
+/// Dentry operations trait - similar to Linux dentry_operations
+pub trait DentryOperations: Send + Sync + core::fmt::Debug {
+	/// Revalidate dentry
+	fn revalidate(&self, dentry: &Dentry) -> Result<bool>;
+
+	/// Hash dentry name
+	fn hash(&self, dentry: &Dentry) -> Result<u32>;
+
+	/// Compare two dentries
+	fn compare(&self, d1: &Dentry, d2: &Dentry) -> Result<bool>;
+
+	/// Delete dentry
+	fn delete(&self, dentry: &Dentry) -> Result<()>;
+
+	/// Release dentry
+	fn release(&self, dentry: &Dentry) -> Result<()>;
+
+	/// Canonicalize path
+	fn canonical_path(&self, dentry: &Dentry) -> Result<String>;
+}
+
+/// Generic dentry operations
+#[derive(Debug)]
+pub struct GenericDentryOps;
+
+impl DentryOperations for GenericDentryOps {
+	fn revalidate(&self, dentry: &Dentry) -> Result<bool> {
+		Ok(true)
+	}
+
+	fn hash(&self, dentry: &Dentry) -> Result<u32> {
+		dentry.hash()
+	}
+
+	fn compare(&self, d1: &Dentry, d2: &Dentry) -> Result<bool> {
+		Ok(d1.d_name == d2.d_name)
+	}
+
+	fn delete(&self, dentry: &Dentry) -> Result<()> {
+		Ok(())
+	}
+
+	fn release(&self, dentry: &Dentry) -> Result<()> {
+		Ok(())
+	}
+
+	fn canonical_path(&self, dentry: &Dentry) -> Result<String> {
+		Ok(dentry.get_path())
+	}
+}
+
+/// Dentry cache (dcache) - simplified version
+pub struct DentryCache {
+	/// Cached dentries
+	cache: Mutex<alloc::collections::BTreeMap<String, Arc<Dentry>>>,
+	/// Hash buckets for faster lookup
+	hash_table: Vec<Mutex<Vec<Arc<Dentry>>>>,
+}
+
+impl DentryCache {
+	/// Create a new dentry cache
+	pub fn new() -> Self {
+		const HASH_BUCKETS: usize = 256;
+		let mut hash_table = Vec::with_capacity(HASH_BUCKETS);
+		for _ in 0..HASH_BUCKETS {
+			hash_table.push(Mutex::new(Vec::new()));
+		}
+
+		Self {
+			cache: Mutex::new(alloc::collections::BTreeMap::new()),
+			hash_table,
+		}
+	}
+
+	/// Look up dentry by path
+	pub fn lookup(&self, path: &str) -> Option<Arc<Dentry>> {
+		let cache = self.cache.lock();
+		cache.get(path).cloned()
+	}
+
+	/// Insert dentry into cache
+	pub fn insert(&self, path: String, dentry: Arc<Dentry>) {
+		let mut cache = self.cache.lock();
+		cache.insert(path, dentry.clone());
+
+		// Also insert into hash table
+		let hash = dentry.d_hash as usize % self.hash_table.len();
+		let mut bucket = self.hash_table[hash].lock();
+		bucket.push(dentry);
+	}
+
+	/// Remove dentry from cache
+	pub fn remove(&self, path: &str) -> Option<Arc<Dentry>> {
+		let mut cache = self.cache.lock();
+		cache.remove(path)
+	}
+
+	/// Prune unused dentries
+	pub fn prune(&self) {
+		let mut cache = self.cache.lock();
+		cache.retain(|_, dentry| dentry.d_count.load(Ordering::Relaxed) > 1);
+
+		// Also prune hash table
+		for bucket in &self.hash_table {
+			let mut bucket = bucket.lock();
+			bucket.retain(|dentry| dentry.d_count.load(Ordering::Relaxed) > 1);
+		}
+	}
+}
+
+/// Global dentry cache
+static DCACHE: spin::once::Once<DentryCache> = spin::once::Once::new();
+
+fn get_dcache() -> &'static DentryCache {
+	DCACHE.call_once(|| DentryCache::new())
+}
+
+/// Look up dentry in cache
+pub fn dcache_lookup(path: &str) -> Option<Arc<Dentry>> {
+	get_dcache().lookup(path)
+}
+
+/// Insert dentry into cache
+pub fn dcache_insert(path: String, dentry: Arc<Dentry>) {
+	get_dcache().insert(path, dentry);
+}
+
+/// Remove dentry from cache
+pub fn dcache_remove(path: &str) -> Option<Arc<Dentry>> {
+	get_dcache().remove(path)
+}
+
+/// Prune dentry cache
+pub fn dcache_prune() {
+	get_dcache().prune();
+}

kernel/src/fs/devfs.rs

@@ -0,0 +1,454 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Character device filesystem integration
+//!
+//! This driver provides VFS integration for character devices
+//! like /dev/null, /dev/zero, /dev/random, etc.
+
+use alloc::{boxed::Box, string::String, vec};
+
+use crate::error::{Error, Result};
+use crate::fs::*;
+use crate::memory::UserSlicePtr;
+use crate::sync::Arc; // Import vec macro and Box
+
+/// Character device file operations
+#[derive(Debug)]
+pub struct CharDevFileOps {
+	/// Device operations
+	dev_ops: Option<Arc<dyn CharDevOperations>>,
+}
+
+impl CharDevFileOps {
+	pub fn new(dev_ops: Option<Arc<dyn CharDevOperations>>) -> Self {
+		Self { dev_ops }
+	}
+}
+
+impl FileOperations for CharDevFileOps {
+	fn read(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		if let Some(ref ops) = self.dev_ops {
+			ops.read(file, buf, count)
+		} else {
+			Err(Error::ENODEV)
+		}
+	}
+
+	fn write(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		if let Some(ref ops) = self.dev_ops {
+			ops.write(file, buf, count)
+		} else {
+			Err(Error::ENODEV)
+		}
+	}
+
+	fn seek(&self, file: &File, offset: i64, whence: i32) -> Result<i64> {
+		// Most character devices don't support seeking
+		Err(Error::ESPIPE)
+	}
+
+	fn ioctl(&self, file: &File, cmd: u32, arg: usize) -> Result<isize> {
+		if let Some(ref ops) = self.dev_ops {
+			ops.ioctl(file, cmd, arg)
+		} else {
+			Err(Error::ENOTTY)
+		}
+	}
+
+	fn mmap(&self, file: &File, vma: &mut crate::memory::VmaArea) -> Result<()> {
+		if let Some(ref ops) = self.dev_ops {
+			ops.mmap(file, vma)
+		} else {
+			Err(Error::ENODEV)
+		}
+	}
+
+	fn fsync(&self, file: &File, datasync: bool) -> Result<()> {
+		// Character devices don't need syncing
+		Ok(())
+	}
+
+	fn poll(&self, file: &File, wait: &mut PollWait) -> Result<u32> {
+		if let Some(ref ops) = self.dev_ops {
+			ops.poll(file, wait)
+		} else {
+			Ok(POLLIN | POLLOUT)
+		}
+	}
+
+	fn open(&self, inode: &Inode, file: &File) -> Result<()> {
+		if let Some(ref ops) = self.dev_ops {
+			ops.open(inode, file)
+		} else {
+			Ok(())
+		}
+	}
+
+	fn release(&self, inode: &Inode, file: &File) -> Result<()> {
+		if let Some(ref ops) = self.dev_ops {
+			ops.release(inode, file)
+		} else {
+			Ok(())
+		}
+	}
+}
+
+/// Character device operations trait
+pub trait CharDevOperations: Send + Sync + core::fmt::Debug {
+	fn read(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize>;
+	fn write(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize>;
+	fn ioctl(&self, file: &File, cmd: u32, arg: usize) -> Result<isize>;
+	fn mmap(&self, file: &File, vma: &mut crate::memory::VmaArea) -> Result<()>;
+	fn poll(&self, file: &File, wait: &mut PollWait) -> Result<u32>;
+	fn open(&self, inode: &Inode, file: &File) -> Result<()>;
+	fn release(&self, inode: &Inode, file: &File) -> Result<()>;
+}
+
+/// /dev/null device operations
+#[derive(Debug)]
+pub struct NullDevOps;
+
+impl CharDevOperations for NullDevOps {
+	fn read(&self, _file: &File, _buf: UserSlicePtr, _count: usize) -> Result<isize> {
+		Ok(0) // EOF
+	}
+
+	fn write(&self, _file: &File, _buf: UserSlicePtr, count: usize) -> Result<isize> {
+		Ok(count as isize) // Discard all data
+	}
+
+	fn ioctl(&self, _file: &File, _cmd: u32, _arg: usize) -> Result<isize> {
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, _file: &File, _vma: &mut crate::memory::VmaArea) -> Result<()> {
+		Err(Error::ENODEV)
+	}
+
+	fn poll(&self, _file: &File, _wait: &mut PollWait) -> Result<u32> {
+		Ok(POLLIN | POLLOUT) // Always ready
+	}
+
+	fn open(&self, _inode: &Inode, _file: &File) -> Result<()> {
+		Ok(())
+	}
+
+	fn release(&self, _inode: &Inode, _file: &File) -> Result<()> {
+		Ok(())
+	}
+}
+
+/// /dev/zero device operations
+#[derive(Debug)]
+pub struct ZeroDevOps;
+
+impl CharDevOperations for ZeroDevOps {
+	fn read(&self, _file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Fill buffer with zeros
+		let zeros = vec![0u8; count];
+		buf.copy_from_slice(&zeros)?;
+		Ok(count as isize)
+	}
+
+	fn write(&self, _file: &File, _buf: UserSlicePtr, count: usize) -> Result<isize> {
+		Ok(count as isize) // Discard all data
+	}
+
+	fn ioctl(&self, _file: &File, _cmd: u32, _arg: usize) -> Result<isize> {
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, _file: &File, _vma: &mut crate::memory::VmaArea) -> Result<()> {
+		// TODO: Map zero page
+		Err(Error::ENODEV)
+	}
+
+	fn poll(&self, _file: &File, _wait: &mut PollWait) -> Result<u32> {
+		Ok(POLLIN | POLLOUT) // Always ready
+	}
+
+	fn open(&self, _inode: &Inode, _file: &File) -> Result<()> {
+		Ok(())
+	}
+
+	fn release(&self, _inode: &Inode, _file: &File) -> Result<()> {
+		Ok(())
+	}
+}
+
+/// /dev/full device operations
+#[derive(Debug)]
+pub struct FullDevOps;
+
+impl CharDevOperations for FullDevOps {
+	fn read(&self, _file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Fill buffer with zeros (like /dev/zero)
+		let zeros = vec![0u8; count];
+		buf.copy_from_slice(&zeros)?;
+		Ok(count as isize)
+	}
+
+	fn write(&self, _file: &File, _buf: UserSlicePtr, _count: usize) -> Result<isize> {
+		Err(Error::ENOSPC) // No space left on device
+	}
+
+	fn ioctl(&self, _file: &File, _cmd: u32, _arg: usize) -> Result<isize> {
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, _file: &File, _vma: &mut crate::memory::VmaArea) -> Result<()> {
+		Err(Error::ENODEV)
+	}
+
+	fn poll(&self, _file: &File, _wait: &mut PollWait) -> Result<u32> {
+		Ok(POLLIN) // Only readable
+	}
+
+	fn open(&self, _inode: &Inode, _file: &File) -> Result<()> {
+		Ok(())
+	}
+
+	fn release(&self, _inode: &Inode, _file: &File) -> Result<()> {
+		Ok(())
+	}
+}
+
+/// /dev/random device operations (simplified)
+#[derive(Debug)]
+pub struct RandomDevOps;
+
+impl CharDevOperations for RandomDevOps {
+	fn read(&self, _file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Generate pseudo-random data
+		// TODO: Use proper random number generator
+		let mut random_data = vec![0u8; count];
+		for i in 0..count {
+			random_data[i] = (i * 37 + 13) as u8; // Very simple PRNG
+		}
+		buf.copy_from_slice(&random_data)?;
+		Ok(count as isize)
+	}
+
+	fn write(&self, _file: &File, _buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// TODO: Add entropy to random pool
+		Ok(count as isize)
+	}
+
+	fn ioctl(&self, _file: &File, _cmd: u32, _arg: usize) -> Result<isize> {
+		// TODO: Implement random device ioctls
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, _file: &File, _vma: &mut crate::memory::VmaArea) -> Result<()> {
+		Err(Error::ENODEV)
+	}
+
+	fn poll(&self, _file: &File, _wait: &mut PollWait) -> Result<u32> {
+		Ok(POLLIN | POLLOUT) // Always ready
+	}
+
+	fn open(&self, _inode: &Inode, _file: &File) -> Result<()> {
+		Ok(())
+	}
+
+	fn release(&self, _inode: &Inode, _file: &File) -> Result<()> {
+		Ok(())
+	}
+}
+
+/// Create a character device inode
+pub fn create_char_device_inode(
+	major: u32,
+	minor: u32,
+	mode: u32,
+	ops: Arc<dyn CharDevOperations>,
+) -> Arc<Inode> {
+	let mut inode = Inode::new(0, mode::S_IFCHR | mode);
+	inode.i_rdev = crate::device::DeviceNumber::new(major, minor);
+	inode.set_file_operations(Arc::new(CharDevFileOps::new(Some(ops))));
+
+	Arc::new(inode)
+}
+
+/// DevFS - device filesystem for /dev
+pub struct DevFs {
+	/// Device entries
+	devices: crate::sync::Mutex<alloc::collections::BTreeMap<String, Arc<Inode>>>,
+}
+
+impl DevFs {
+	pub fn new() -> Self {
+		let mut devfs = Self {
+			devices: crate::sync::Mutex::new(alloc::collections::BTreeMap::new()),
+		};
+
+		devfs.create_standard_devices();
+		devfs
+	}
+
+	fn create_standard_devices(&mut self) {
+		// Create /dev/null
+		let null_inode = create_char_device_inode(1, 3, 0o666, Arc::new(NullDevOps));
+		self.add_device("null", null_inode);
+
+		// Create /dev/zero
+		let zero_inode = create_char_device_inode(1, 5, 0o666, Arc::new(ZeroDevOps));
+		self.add_device("zero", zero_inode);
+
+		// Create /dev/full
+		let full_inode = create_char_device_inode(1, 7, 0o666, Arc::new(FullDevOps));
+		self.add_device("full", full_inode);
+
+		// Create /dev/random
+		let random_inode = create_char_device_inode(1, 8, 0o666, Arc::new(RandomDevOps));
+		self.add_device("random", random_inode);
+
+		// Create /dev/urandom (same as random for now)
+		let urandom_inode = create_char_device_inode(1, 9, 0o666, Arc::new(RandomDevOps));
+		self.add_device("urandom", urandom_inode);
+	}
+
+	pub fn add_device(&mut self, name: &str, inode: Arc<Inode>) {
+		let mut devices = self.devices.lock();
+		devices.insert(String::from(name), inode);
+	}
+
+	pub fn get_device(&self, name: &str) -> Option<Arc<Inode>> {
+		let devices = self.devices.lock();
+		devices.get(name).cloned()
+	}
+
+	pub fn list_devices(&self) -> alloc::vec::Vec<String> {
+		let devices = self.devices.lock();
+		devices.keys().cloned().collect()
+	}
+}
+
+/// DevFS inode operations
+#[derive(Debug)]
+pub struct DevFsInodeOps {
+	devfs: *const DevFs,
+}
+
+impl DevFsInodeOps {
+	pub fn new(devfs: &DevFs) -> Self {
+		Self {
+			devfs: devfs as *const DevFs,
+		}
+	}
+
+	fn get_devfs(&self) -> &DevFs {
+		unsafe { &*self.devfs }
+	}
+}
+
+unsafe impl Send for DevFsInodeOps {}
+unsafe impl Sync for DevFsInodeOps {}
+
+impl InodeOperations for DevFsInodeOps {
+	fn lookup(&self, dir: &Inode, name: &str) -> Result<Arc<Inode>> {
+		let devfs = self.get_devfs();
+		devfs.get_device(name).ok_or(Error::ENOENT)
+	}
+
+	fn create(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		Err(Error::EPERM) // Can't create devices in /dev directly
+	}
+
+	fn mkdir(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		Err(Error::EPERM)
+	}
+
+	fn unlink(&self, dir: &Inode, name: &str) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn rmdir(&self, dir: &Inode, name: &str) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn symlink(&self, dir: &Inode, name: &str, target: &str) -> Result<Arc<Inode>> {
+		Err(Error::EPERM)
+	}
+
+	fn rename(
+		&self,
+		old_dir: &Inode,
+		old_name: &str,
+		new_dir: &Inode,
+		new_name: &str,
+	) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn setattr(&self, inode: &Inode, attr: &InodeAttr) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn getattr(&self, inode: &Inode) -> Result<InodeAttr> {
+		let generic_ops = GenericInodeOps;
+		generic_ops.getattr(inode)
+	}
+
+	fn readlink(&self, inode: &Inode) -> Result<String> {
+		Err(Error::EINVAL)
+	}
+
+	fn follow_link(&self, inode: &Inode) -> Result<Arc<Inode>> {
+		Err(Error::EINVAL)
+	}
+
+	fn truncate(&self, inode: &Inode, size: u64) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn getxattr(&self, inode: &Inode, name: &str) -> Result<alloc::vec::Vec<u8>> {
+		Err(Error::ENODATA)
+	}
+
+	fn setxattr(&self, inode: &Inode, name: &str, value: &[u8], flags: u32) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn listxattr(&self, inode: &Inode) -> Result<alloc::vec::Vec<String>> {
+		Ok(alloc::vec::Vec::new())
+	}
+
+	fn removexattr(&self, inode: &Inode, name: &str) -> Result<()> {
+		Err(Error::EPERM)
+	}
+}
+
+/// Mount devfs
+pub fn mount_devfs(_dev_name: &str, _flags: u32, _data: Option<&str>) -> Result<Arc<SuperBlock>> {
+	let mut sb = SuperBlock::new("devfs")?;
+	sb.s_magic = 0x1373; // DEVFS magic
+
+	let devfs = Box::leak(Box::new(DevFs::new()));
+	sb.s_fs_info = Some(devfs as *mut DevFs as *mut u8);
+
+	// Create root inode
+	let root_inode = Arc::new({
+		let mut inode = Inode::new(1, mode::S_IFDIR | 0o755);
+		inode.set_operations(Arc::new(DevFsInodeOps::new(devfs)));
+		inode
+	});
+
+	let root_dentry = Arc::new(Dentry::new(String::from("/"), Some(root_inode)));
+	sb.s_root = Some(root_dentry);
+
+	Ok(Arc::new(sb))
+}
+
+/// Register devfs filesystem
+pub fn register_devfs() -> Result<()> {
+	let devfs_type = FileSystemType::new(
+		String::from("devfs"),
+		|_fstype, flags, _dev_name, data| mount_devfs(_dev_name, flags, data),
+		|_sb| Ok(()),
+	);
+
+	// TODO: Register with VFS
+	crate::console::print_info("Registered devfs filesystem\n");
+	Ok(())
+}

kernel/src/fs/file.rs

@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! File abstraction - Linux compatible
+
+use alloc::string::String;
+use core::sync::atomic::{AtomicI64, AtomicU32, Ordering};
+
+use crate::error::{Error, Result};
+// use crate::types::*;  // Commented out - unused for now
+use crate::memory::UserSlicePtr; // Remove UserPtr since it's unused
+use crate::sync::Arc; // Remove Mutex and RwLock since they're unused
+
+/// File structure - similar to Linux struct file
+#[derive(Debug)]
+pub struct File {
+	/// File operations
+	pub f_op: Option<Arc<dyn FileOperations>>,
+	/// Current file position
+	pub pos: AtomicI64,
+	/// File flags
+	pub flags: AtomicU32,
+	/// File mode
+	pub mode: u32,
+	/// Associated inode
+	pub inode: Option<Arc<super::Inode>>,
+	/// Associated dentry
+	pub dentry: Option<Arc<super::Dentry>>,
+	/// Private data for file operations
+	pub private_data: Option<*mut u8>,
+	/// File path (for debugging/proc)
+	pub path: String,
+	/// Reference count
+	pub refcount: AtomicU32,
+}
+
+impl File {
+	/// Create a new file
+	pub fn new(path: &str, flags: u32, mode: u32) -> Result<Self> {
+		Ok(Self {
+			f_op: None,
+			pos: AtomicI64::new(0),
+			flags: AtomicU32::new(flags),
+			mode,
+			inode: None,
+			dentry: None,
+			private_data: None,
+			path: String::from(path),
+			refcount: AtomicU32::new(1),
+		})
+	}
+
+	/// Set file operations
+	pub fn set_operations(&mut self, ops: Arc<dyn FileOperations>) {
+		self.f_op = Some(ops);
+	}
+
+	/// Read from file
+	pub fn read(&self, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		if let Some(ref ops) = self.f_op {
+			ops.read(self, buf, count)
+		} else {
+			Err(Error::ENOSYS)
+		}
+	}
+
+	/// Write to file
+	pub fn write(&self, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		if let Some(ref ops) = self.f_op {
+			ops.write(self, buf, count)
+		} else {
+			Err(Error::ENOSYS)
+		}
+	}
+
+	/// Seek within file
+	pub fn seek(&self, offset: i64, whence: i32) -> Result<i64> {
+		if let Some(ref ops) = self.f_op {
+			let new_pos = ops.seek(self, offset, whence)?;
+			self.pos.store(new_pos, Ordering::Relaxed);
+			Ok(new_pos)
+		} else {
+			Err(Error::ENOSYS)
+		}
+	}
+
+	/// Get file status
+	pub fn stat(&self) -> Result<super::KStat> {
+		if let Some(ref inode) = self.inode {
+			inode.stat()
+		} else {
+			// Create a basic stat structure
+			Ok(super::KStat {
+				st_dev: 0,
+				st_ino: 0,
+				st_nlink: 1,
+				st_mode: self.mode,
+				st_uid: 0,
+				st_gid: 0,
+				st_rdev: 0,
+				st_size: 0,
+				st_blksize: 4096,
+				st_blocks: 0,
+				st_atime: 0,
+				st_atime_nsec: 0,
+				st_mtime: 0,
+				st_mtime_nsec: 0,
+				st_ctime: 0,
+				st_ctime_nsec: 0,
+			})
+		}
+	}
+
+	/// Perform ioctl operation
+	pub fn ioctl(&self, cmd: u32, arg: usize) -> Result<isize> {
+		if let Some(ref ops) = self.f_op {
+			ops.ioctl(self, cmd, arg)
+		} else {
+			Err(Error::ENOTTY)
+		}
+	}
+
+	/// Memory map file
+	pub fn mmap(&self, vma: &mut crate::memory::VmaArea) -> Result<()> {
+		if let Some(ref ops) = self.f_op {
+			ops.mmap(self, vma)
+		} else {
+			Err(Error::ENODEV)
+		}
+	}
+
+	/// Sync file to storage
+	pub fn fsync(&self, datasync: bool) -> Result<()> {
+		if let Some(ref ops) = self.f_op {
+			ops.fsync(self, datasync)
+		} else {
+			Ok(()) // No-op for files without sync
+		}
+	}
+
+	/// Poll file for events
+	pub fn poll(&self, wait: &mut super::PollWait) -> Result<u32> {
+		if let Some(ref ops) = self.f_op {
+			ops.poll(self, wait)
+		} else {
+			Ok(super::POLLIN | super::POLLOUT) // Always ready
+		}
+	}
+
+	/// Get current file position
+	pub fn get_pos(&self) -> i64 {
+		self.pos.load(Ordering::Relaxed)
+	}
+
+	/// Set file position
+	pub fn set_pos(&self, pos: i64) {
+		self.pos.store(pos, Ordering::Relaxed);
+	}
+
+	/// Get file flags
+	pub fn get_flags(&self) -> u32 {
+		self.flags.load(Ordering::Relaxed)
+	}
+
+	/// Check if file is readable
+	pub fn is_readable(&self) -> bool {
+		let flags = self.get_flags();
+		(flags & super::flags::O_ACCMODE) != super::flags::O_WRONLY
+	}
+
+	/// Check if file is writable
+	pub fn is_writable(&self) -> bool {
+		let flags = self.get_flags();
+		(flags & super::flags::O_ACCMODE) != super::flags::O_RDONLY
+	}
+
+	/// Increment reference count
+	pub fn get_file(&self) -> Result<()> {
+		self.refcount.fetch_add(1, Ordering::Relaxed);
+		Ok(())
+	}
+
+	/// Decrement reference count (fput equivalent)
+	pub fn put_file(&self) -> Result<()> {
+		let old_count = self.refcount.fetch_sub(1, Ordering::Relaxed);
+		if old_count == 1 {
+			// Last reference, file should be cleaned up
+			// TODO: Call release operation if present
+		}
+		Ok(())
+	}
+}
+
+unsafe impl Send for File {}
+unsafe impl Sync for File {}
+
+/// File operations trait - similar to Linux file_operations
+pub trait FileOperations: Send + Sync + core::fmt::Debug {
+	/// Read from file
+	fn read(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize>;
+
+	/// Write to file
+	fn write(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize>;
+
+	/// Seek within file
+	fn seek(&self, file: &File, offset: i64, whence: i32) -> Result<i64>;
+
+	/// I/O control
+	fn ioctl(&self, file: &File, cmd: u32, arg: usize) -> Result<isize>;
+
+	/// Memory map
+	fn mmap(&self, file: &File, vma: &mut crate::memory::VmaArea) -> Result<()>;
+
+	/// Sync file
+	fn fsync(&self, file: &File, datasync: bool) -> Result<()>;
+
+	/// Poll for events
+	fn poll(&self, file: &File, wait: &mut super::PollWait) -> Result<u32>;
+
+	/// Open file (optional)
+	fn open(&self, inode: &super::Inode, file: &File) -> Result<()> {
+		Ok(())
+	}
+
+	/// Release file (optional)
+	fn release(&self, inode: &super::Inode, file: &File) -> Result<()> {
+		Ok(())
+	}
+
+	/// Flush file (optional)
+	fn flush(&self, file: &File) -> Result<()> {
+		Ok(())
+	}
+
+	/// Lock file (optional)
+	fn lock(&self, file: &File, cmd: i32) -> Result<()> {
+		Err(Error::ENOSYS)
+	}
+
+	/// Read directory entries (optional)
+	fn readdir(&self, file: &File, ctx: &mut super::DirContext) -> Result<()> {
+		Err(Error::ENOTDIR)
+	}
+}
+
+/// Directory context for readdir operations
+pub struct DirContext {
+	/// Current position in directory
+	pub pos: i64,
+	/// Entries collected so far
+	pub entries: alloc::vec::Vec<super::DirEntry>,
+}
+
+impl DirContext {
+	pub fn new(pos: i64) -> Self {
+		Self {
+			pos,
+			entries: alloc::vec::Vec::new(),
+		}
+	}
+
+	/// Add a directory entry
+	pub fn add_entry(&mut self, ino: u64, name: &str, d_type: u8) {
+		let entry = super::DirEntry {
+			ino,
+			off: self.pos,
+			reclen: (core::mem::size_of::<super::DirEntry>() + name.len() + 1) as u16,
+			name: String::from(name),
+			d_type,
+		};
+		self.entries.push(entry);
+		self.pos += 1;
+	}
+}

kernel/src/fs/inode.rs

@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Inode abstraction - Linux compatible
+
+use alloc::string::String;
+use core::sync::atomic::{AtomicU32, AtomicU64, Ordering};
+
+use crate::device::DeviceNumber;
+use crate::error::{Error, Result};
+use crate::sync::{Arc, Mutex};
+use crate::time::{get_current_time, TimeSpec};
+
+/// Inode structure - similar to Linux struct inode
+#[derive(Debug)]
+pub struct Inode {
+	/// Inode number
+	pub i_ino: u64,
+	/// File mode and type
+	pub i_mode: AtomicU32,
+	/// Number of hard links
+	pub i_nlink: AtomicU32,
+	/// User ID
+	pub i_uid: AtomicU32,
+	/// Group ID
+	pub i_gid: AtomicU32,
+	/// Device number (for device files)
+	pub i_rdev: DeviceNumber,
+	/// File size
+	pub i_size: AtomicU64,
+	/// Block size
+	pub i_blksize: u32,
+	/// Number of blocks
+	pub i_blocks: AtomicU64,
+	/// Access time
+	pub i_atime: Mutex<TimeSpec>,
+	/// Modification time
+	pub i_mtime: Mutex<TimeSpec>,
+	/// Status change time
+	pub i_ctime: Mutex<TimeSpec>,
+	/// Inode operations
+	pub i_op: Option<Arc<dyn InodeOperations>>,
+	/// File operations (for regular files)
+	pub i_fop: Option<Arc<dyn super::FileOperations>>,
+	/// Superblock this inode belongs to
+	pub i_sb: Option<Arc<super::SuperBlock>>,
+	/// Private data
+	pub private_data: Option<*mut u8>,
+	/// Reference count
+	pub refcount: AtomicU32,
+	/// Inode flags
+	pub i_flags: AtomicU32,
+}
+
+impl Inode {
+	/// Create a new inode
+	pub fn new(ino: u64, mode: u32) -> Self {
+		let now = get_current_time();
+		Self {
+			i_ino: ino,
+			i_mode: AtomicU32::new(mode),
+			i_nlink: AtomicU32::new(1),
+			i_uid: AtomicU32::new(0),
+			i_gid: AtomicU32::new(0),
+			i_rdev: DeviceNumber::new(0, 0),
+			i_size: AtomicU64::new(0),
+			i_blksize: 4096,
+			i_blocks: AtomicU64::new(0),
+			i_atime: Mutex::new(now),
+			i_mtime: Mutex::new(now),
+			i_ctime: Mutex::new(now),
+			i_op: None,
+			i_fop: None,
+			i_sb: None,
+			private_data: None,
+			refcount: AtomicU32::new(1),
+			i_flags: AtomicU32::new(0),
+		}
+	}
+
+	/// Set inode operations
+	pub fn set_operations(&mut self, ops: Arc<dyn InodeOperations>) {
+		self.i_op = Some(ops);
+	}
+
+	/// Set file operations
+	pub fn set_file_operations(&mut self, ops: Arc<dyn super::FileOperations>) {
+		self.i_fop = Some(ops);
+	}
+
+	/// Get file statistics
+	pub fn stat(&self) -> Result<super::KStat> {
+		let atime = self.i_atime.lock();
+		let mtime = self.i_mtime.lock();
+		let ctime = self.i_ctime.lock();
+
+		Ok(super::KStat {
+			st_dev: if let Some(ref sb) = self.i_sb {
+				sb.s_dev.as_raw()
+			} else {
+				0
+			},
+			st_ino: self.i_ino,
+			st_nlink: self.i_nlink.load(Ordering::Relaxed) as u64,
+			st_mode: self.i_mode.load(Ordering::Relaxed),
+			st_uid: self.i_uid.load(Ordering::Relaxed),
+			st_gid: self.i_gid.load(Ordering::Relaxed),
+			st_rdev: self.i_rdev.as_raw(),
+			st_size: self.i_size.load(Ordering::Relaxed) as i64,
+			st_blksize: self.i_blksize as u64,
+			st_blocks: self.i_blocks.load(Ordering::Relaxed),
+			st_atime: atime.tv_sec,
+			st_atime_nsec: atime.tv_nsec,
+			st_mtime: mtime.tv_sec,
+			st_mtime_nsec: mtime.tv_nsec,
+			st_ctime: ctime.tv_sec,
+			st_ctime_nsec: ctime.tv_nsec,
+		})
+	}
+
+	/// Check if inode is a regular file
+	pub fn is_regular(&self) -> bool {
+		let mode = self.i_mode.load(Ordering::Relaxed);
+		super::mode::s_isreg(mode)
+	}
+
+	/// Check if inode is a directory
+	pub fn is_directory(&self) -> bool {
+		let mode = self.i_mode.load(Ordering::Relaxed);
+		super::mode::s_isdir(mode)
+	}
+
+	/// Check if inode is a character device
+	pub fn is_char_device(&self) -> bool {
+		let mode = self.i_mode.load(Ordering::Relaxed);
+		super::mode::s_ischr(mode)
+	}
+
+	/// Check if inode is a block device
+	pub fn is_block_device(&self) -> bool {
+		let mode = self.i_mode.load(Ordering::Relaxed);
+		super::mode::s_isblk(mode)
+	}
+
+	/// Update access time
+	pub fn update_atime(&self) {
+		let mut atime = self.i_atime.lock();
+		*atime = get_current_time();
+	}
+
+	/// Update modification time
+	pub fn update_mtime(&self) {
+		let mut mtime = self.i_mtime.lock();
+		*mtime = get_current_time();
+	}
+
+	/// Update status change time
+	pub fn update_ctime(&self) {
+		let mut ctime = self.i_ctime.lock();
+		*ctime = get_current_time();
+	}
+
+	/// Set file size
+	pub fn set_size(&self, size: u64) {
+		self.i_size.store(size, Ordering::Relaxed);
+		self.update_mtime();
+		self.update_ctime();
+	}
+
+	/// Get file size
+	pub fn get_size(&self) -> u64 {
+		self.i_size.load(Ordering::Relaxed)
+	}
+
+	/// Increment reference count
+	pub fn iget(&self) {
+		self.refcount.fetch_add(1, Ordering::Relaxed);
+	}
+
+	/// Decrement reference count
+	pub fn iput(&self) {
+		let old_count = self.refcount.fetch_sub(1, Ordering::Relaxed);
+		if old_count == 1 {
+			// Last reference, inode should be cleaned up
+			// TODO: Call destroy_inode operation if present
+		}
+	}
+
+	/// Create a new file in this directory
+	pub fn create(&self, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		if let Some(ref ops) = self.i_op {
+			ops.create(self, name, mode)
+		} else {
+			Err(Error::ENOSYS)
+		}
+	}
+
+	/// Look up a file in this directory
+	pub fn lookup(&self, name: &str) -> Result<Arc<Inode>> {
+		if let Some(ref ops) = self.i_op {
+			ops.lookup(self, name)
+		} else {
+			Err(Error::ENOSYS)
+		}
+	}
+
+	/// Create a directory
+	pub fn mkdir(&self, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		if let Some(ref ops) = self.i_op {
+			ops.mkdir(self, name, mode)
+		} else {
+			Err(Error::ENOSYS)
+		}
+	}
+
+	/// Remove a file
+	pub fn unlink(&self, name: &str) -> Result<()> {
+		if let Some(ref ops) = self.i_op {
+			ops.unlink(self, name)
+		} else {
+			Err(Error::ENOSYS)
+		}
+	}
+
+	/// Remove a directory
+	pub fn rmdir(&self, name: &str) -> Result<()> {
+		if let Some(ref ops) = self.i_op {
+			ops.rmdir(self, name)
+		} else {
+			Err(Error::ENOSYS)
+		}
+	}
+}
+
+unsafe impl Send for Inode {}
+unsafe impl Sync for Inode {}
+
+/// Inode operations trait - similar to Linux inode_operations
+pub trait InodeOperations: Send + Sync + core::fmt::Debug {
+	/// Look up a file in directory
+	fn lookup(&self, dir: &Inode, name: &str) -> Result<Arc<Inode>>;
+
+	/// Create a new file
+	fn create(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>>;
+
+	/// Create a directory
+	fn mkdir(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>>;
+
+	/// Remove a file
+	fn unlink(&self, dir: &Inode, name: &str) -> Result<()>;
+
+	/// Remove a directory
+	fn rmdir(&self, dir: &Inode, name: &str) -> Result<()>;
+
+	/// Create a symbolic link
+	fn symlink(&self, dir: &Inode, name: &str, target: &str) -> Result<Arc<Inode>>;
+
+	/// Rename a file
+	fn rename(
+		&self,
+		old_dir: &Inode,
+		old_name: &str,
+		new_dir: &Inode,
+		new_name: &str,
+	) -> Result<()>;
+
+	/// Set attributes
+	fn setattr(&self, inode: &Inode, attr: &InodeAttr) -> Result<()>;
+
+	/// Get attributes
+	fn getattr(&self, inode: &Inode) -> Result<InodeAttr>;
+
+	/// Read symbolic link
+	fn readlink(&self, inode: &Inode) -> Result<String>;
+
+	/// Follow symbolic link
+	fn follow_link(&self, inode: &Inode) -> Result<Arc<Inode>>;
+
+	/// Truncate file
+	fn truncate(&self, inode: &Inode, size: u64) -> Result<()>;
+
+	/// Get extended attribute
+	fn getxattr(&self, inode: &Inode, name: &str) -> Result<alloc::vec::Vec<u8>>;
+
+	/// Set extended attribute
+	fn setxattr(&self, inode: &Inode, name: &str, value: &[u8], flags: u32) -> Result<()>;
+
+	/// List extended attributes
+	fn listxattr(&self, inode: &Inode) -> Result<alloc::vec::Vec<String>>;
+
+	/// Remove extended attribute
+	fn removexattr(&self, inode: &Inode, name: &str) -> Result<()>;
+}
+
+/// Inode attributes structure
+#[derive(Debug, Clone, Copy)]
+pub struct InodeAttr {
+	pub mode: Option<u32>,
+	pub uid: Option<u32>,
+	pub gid: Option<u32>,
+	pub size: Option<u64>,
+	pub atime: Option<TimeSpec>,
+	pub mtime: Option<TimeSpec>,
+	pub ctime: Option<TimeSpec>,
+}
+
+impl InodeAttr {
+	pub fn new() -> Self {
+		Self {
+			mode: None,
+			uid: None,
+			gid: None,
+			size: None,
+			atime: None,
+			mtime: None,
+			ctime: None,
+		}
+	}
+
+	pub fn with_mode(mut self, mode: u32) -> Self {
+		self.mode = Some(mode);
+		self
+	}
+
+	pub fn with_size(mut self, size: u64) -> Self {
+		self.size = Some(size);
+		self
+	}
+}
+
+/// Generic inode operations for simple filesystems
+#[derive(Debug)]
+pub struct GenericInodeOps;
+
+impl InodeOperations for GenericInodeOps {
+	fn lookup(&self, dir: &Inode, name: &str) -> Result<Arc<Inode>> {
+		Err(Error::ENOENT)
+	}
+
+	fn create(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		Err(Error::ENOSYS)
+	}
+
+	fn mkdir(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		Err(Error::ENOSYS)
+	}
+
+	fn unlink(&self, dir: &Inode, name: &str) -> Result<()> {
+		Err(Error::ENOSYS)
+	}
+
+	fn rmdir(&self, dir: &Inode, name: &str) -> Result<()> {
+		Err(Error::ENOSYS)
+	}
+
+	fn symlink(&self, dir: &Inode, name: &str, target: &str) -> Result<Arc<Inode>> {
+		Err(Error::ENOSYS)
+	}
+
+	fn rename(
+		&self,
+		old_dir: &Inode,
+		old_name: &str,
+		new_dir: &Inode,
+		new_name: &str,
+	) -> Result<()> {
+		Err(Error::ENOSYS)
+	}
+
+	fn setattr(&self, inode: &Inode, attr: &InodeAttr) -> Result<()> {
+		// Apply basic attributes
+		if let Some(mode) = attr.mode {
+			inode.i_mode.store(mode, Ordering::Relaxed);
+		}
+		if let Some(uid) = attr.uid {
+			inode.i_uid.store(uid, Ordering::Relaxed);
+		}
+		if let Some(gid) = attr.gid {
+			inode.i_gid.store(gid, Ordering::Relaxed);
+		}
+		if let Some(size) = attr.size {
+			inode.set_size(size);
+		}
+		if let Some(atime) = attr.atime {
+			*inode.i_atime.lock() = atime;
+		}
+		if let Some(mtime) = attr.mtime {
+			*inode.i_mtime.lock() = mtime;
+		}
+		if let Some(ctime) = attr.ctime {
+			*inode.i_ctime.lock() = ctime;
+		}
+		Ok(())
+	}
+
+	fn getattr(&self, inode: &Inode) -> Result<InodeAttr> {
+		Ok(InodeAttr {
+			mode: Some(inode.i_mode.load(Ordering::Relaxed)),
+			uid: Some(inode.i_uid.load(Ordering::Relaxed)),
+			gid: Some(inode.i_gid.load(Ordering::Relaxed)),
+			size: Some(inode.i_size.load(Ordering::Relaxed)),
+			atime: Some(*inode.i_atime.lock()),
+			mtime: Some(*inode.i_mtime.lock()),
+			ctime: Some(*inode.i_ctime.lock()),
+		})
+	}
+
+	fn readlink(&self, inode: &Inode) -> Result<String> {
+		Err(Error::EINVAL)
+	}
+
+	fn follow_link(&self, inode: &Inode) -> Result<Arc<Inode>> {
+		Err(Error::EINVAL)
+	}
+
+	fn truncate(&self, inode: &Inode, size: u64) -> Result<()> {
+		inode.set_size(size);
+		Ok(())
+	}
+
+	fn getxattr(&self, inode: &Inode, name: &str) -> Result<alloc::vec::Vec<u8>> {
+		Err(Error::ENODATA)
+	}
+
+	fn setxattr(&self, inode: &Inode, name: &str, value: &[u8], flags: u32) -> Result<()> {
+		Err(Error::ENOSYS)
+	}
+
+	fn listxattr(&self, inode: &Inode) -> Result<alloc::vec::Vec<String>> {
+		Ok(alloc::vec::Vec::new())
+	}
+
+	fn removexattr(&self, inode: &Inode, name: &str) -> Result<()> {
+		Err(Error::ENODATA)
+	}
+}

kernel/src/fs/mod.rs

@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Virtual File System (VFS) - Linux compatible
+//!
+//! This module provides the core filesystem abstractions and compatibility
+//! with Linux VFS operations.
+
+pub mod dentry;
+pub mod devfs;
+pub mod file;
+pub mod inode;
+pub mod mode;
+pub mod mount;
+pub mod operations;
+pub mod path;
+pub mod procfs;
+pub mod ramfs;
+pub mod super_block; // Add mode module
+		     // pub mod advanced;  // Advanced file system operations (removed for now)
+
+use alloc::collections::BTreeMap;
+use alloc::string::String;
+use alloc::vec::Vec;
+
+pub use dentry::*;
+pub use file::*;
+pub use inode::*;
+pub use mount::*;
+pub use operations::*;
+pub use path::*;
+pub use super_block::*;
+
+use crate::error::{Error, Result};
+use crate::memory::{UserPtr, UserSlicePtr};
+use crate::sync::{Arc, Mutex};
+
+/// File access modes - Linux compatible
+pub mod flags {
+	pub const O_ACCMODE: u32 = 0o00000003;
+	pub const O_RDONLY: u32 = 0o00000000;
+	pub const O_WRONLY: u32 = 0o00000001;
+	pub const O_RDWR: u32 = 0o00000002;
+	pub const O_CREAT: u32 = 0o00000100;
+	pub const O_EXCL: u32 = 0o00000200;
+	pub const O_NOCTTY: u32 = 0o00000400;
+	pub const O_TRUNC: u32 = 0o00001000;
+	pub const O_APPEND: u32 = 0o00002000;
+	pub const O_NONBLOCK: u32 = 0o00004000;
+	pub const O_DSYNC: u32 = 0o00010000;
+	pub const O_FASYNC: u32 = 0o00020000;
+	pub const O_DIRECT: u32 = 0o00040000;
+	pub const O_LARGEFILE: u32 = 0o00100000;
+	pub const O_DIRECTORY: u32 = 0o00200000;
+	pub const O_NOFOLLOW: u32 = 0o00400000;
+	pub const O_NOATIME: u32 = 0o01000000;
+	pub const O_CLOEXEC: u32 = 0o02000000;
+	pub const O_SYNC: u32 = 0o04000000 | O_DSYNC;
+	pub const O_PATH: u32 = 0o10000000;
+	pub const O_TMPFILE: u32 = 0o20000000 | O_DIRECTORY;
+}
+
+/// Seek constants
+pub const SEEK_SET: i32 = 0;
+pub const SEEK_CUR: i32 = 1;
+pub const SEEK_END: i32 = 2;
+pub const SEEK_DATA: i32 = 3;
+pub const SEEK_HOLE: i32 = 4;
+
+/// Maximum filename length
+pub const NAME_MAX: usize = 255;
+
+/// Maximum path length
+pub const PATH_MAX: usize = 4096;
+
+/// File system statistics structure
+#[repr(C)]
+#[derive(Debug, Clone, Copy)]
+pub struct KStatFs {
+	pub f_type: u64,
+	pub f_bsize: u64,
+	pub f_blocks: u64,
+	pub f_bfree: u64,
+	pub f_bavail: u64,
+	pub f_files: u64,
+	pub f_ffree: u64,
+	pub f_fsid: [u32; 2],
+	pub f_namelen: u64,
+	pub f_frsize: u64,
+	pub f_flags: u64,
+	pub f_spare: [u64; 4],
+}
+
+/// File attributes structure
+#[repr(C)]
+#[derive(Debug, Clone, Copy)]
+pub struct KStat {
+	pub st_dev: u64,
+	pub st_ino: u64,
+	pub st_nlink: u64,
+	pub st_mode: u32,
+	pub st_uid: u32,
+	pub st_gid: u32,
+	pub st_rdev: u64,
+	pub st_size: i64,
+	pub st_blksize: u64,
+	pub st_blocks: u64,
+	pub st_atime: i64,
+	pub st_atime_nsec: i64,
+	pub st_mtime: i64,
+	pub st_mtime_nsec: i64,
+	pub st_ctime: i64,
+	pub st_ctime_nsec: i64,
+}
+
+/// I/O vector for scatter-gather I/O
+#[repr(C)]
+#[derive(Debug, Clone, Copy)]
+pub struct IoVec {
+	pub iov_base: *mut u8,
+	pub iov_len: usize,
+}
+
+/// Directory entry type returned by readdir
+#[derive(Debug, Clone)]
+pub struct DirEntry {
+	pub ino: u64,
+	pub off: i64,
+	pub reclen: u16,
+	pub name: String,
+	pub d_type: u8,
+}
+
+/// Directory entry types
+pub const DT_UNKNOWN: u8 = 0;
+pub const DT_FIFO: u8 = 1;
+pub const DT_CHR: u8 = 2;
+pub const DT_DIR: u8 = 4;
+pub const DT_BLK: u8 = 6;
+pub const DT_REG: u8 = 8;
+pub const DT_LNK: u8 = 10;
+pub const DT_SOCK: u8 = 12;
+pub const DT_WHT: u8 = 14;
+
+/// Global VFS state
+static VFS: Mutex<Vfs> = Mutex::new(Vfs::new());
+
+/// Global file descriptor table (simplified - in reality this would be
+/// per-process)
+static GLOBAL_FD_TABLE: Mutex<BTreeMap<i32, Arc<File>>> = Mutex::new(BTreeMap::new());
+static NEXT_FD: core::sync::atomic::AtomicI32 = core::sync::atomic::AtomicI32::new(3); // Start after stdin/stdout/stderr
+
+/// Virtual File System state
+pub struct Vfs {
+	/// Mounted filesystems
+	pub mounts: Vec<Arc<VfsMount>>,
+	/// Root dentry
+	pub root: Option<Arc<Dentry>>,
+	/// File descriptor table (per-process will be separate)
+	pub fd_table: BTreeMap<i32, Arc<File>>,
+	/// Next file descriptor number
+	pub next_fd: i32,
+}
+
+impl Vfs {
+	const fn new() -> Self {
+		Self {
+			mounts: Vec::new(),
+			root: None,
+			fd_table: BTreeMap::new(),
+			next_fd: 0,
+		}
+	}
+
+	/// Mount a filesystem
+	pub fn mount(
+		&mut self,
+		source: &str,
+		target: &str,
+		fstype: &str,
+		flags: u32,
+		data: Option<&str>,
+	) -> Result<()> {
+		// TODO: Implement proper mount logic
+		// For now, just create a basic mount
+		let sb = Arc::new(SuperBlock::new(fstype)?);
+		let mount = Arc::new(VfsMount::new(sb, target, flags)?);
+		self.mounts.push(mount);
+		Ok(())
+	}
+
+	/// Allocate a new file descriptor
+	pub fn alloc_fd(&mut self) -> i32 {
+		let fd = self.next_fd;
+		self.next_fd += 1;
+		fd
+	}
+
+	/// Install a file into the file descriptor table
+	pub fn install_fd(&mut self, fd: i32, file: Arc<File>) {
+		self.fd_table.insert(fd, file);
+	}
+
+	/// Get a file by file descriptor
+	pub fn get_file(&self, fd: i32) -> Option<Arc<File>> {
+		self.fd_table.get(&fd).cloned()
+	}
+
+	/// Close a file descriptor
+	pub fn close_fd(&mut self, fd: i32) -> Result<()> {
+		self.fd_table.remove(&fd);
+		Ok(())
+	}
+}
+
+/// Initialize the VFS subsystem
+pub fn init() -> Result<()> {
+	// Register built-in filesystems
+	ramfs::register_ramfs()?;
+	procfs::register_procfs()?;
+	devfs::register_devfs()?;
+
+	// Create initial mounts
+	mount::do_mount("none", "/", "ramfs", 0, None)?;
+
+	// Create essential directories
+	// TODO: Create /proc and /dev directories in root filesystem
+
+	mount::do_mount("proc", "/proc", "proc", 0, None)?;
+	mount::do_mount("devfs", "/dev", "devfs", 0, None)?;
+
+	crate::console::print_info("VFS: Initialized virtual file system\n");
+	Ok(())
+}
+
+/// Get a file descriptor from the table
+pub fn get_file_descriptor(fd: i32) -> Option<Arc<File>> {
+	let table = GLOBAL_FD_TABLE.lock();
+	table.get(&fd).cloned()
+}
+
+/// Allocate a new file descriptor
+pub fn allocate_file_descriptor(file: Arc<File>) -> Result<i32> {
+	let fd = NEXT_FD.fetch_add(1, core::sync::atomic::Ordering::SeqCst);
+	let mut table = GLOBAL_FD_TABLE.lock();
+	table.insert(fd, file);
+	Ok(fd)
+}
+
+/// Close a file descriptor
+pub fn close_file_descriptor(fd: i32) -> Result<()> {
+	let mut table = GLOBAL_FD_TABLE.lock();
+	table.remove(&fd).ok_or(Error::EBADF)?;
+	Ok(())
+}
+
+/// Open a file
+pub fn open_file(path: &str, flags: i32, mode: u32) -> Result<Arc<File>> {
+	// For now, create a simple file structure
+	// In a full implementation, this would:
+	// 1. Parse the path
+	// 2. Walk the directory tree
+	// 3. Check permissions
+	// 4. Create inode/dentry structures
+	// 5. Return file handle
+
+	let file = File::new(path, flags as u32, mode)?;
+
+	Ok(Arc::new(file))
+}
+
+/// Read from a file
+pub fn read_file(file: &Arc<File>, buf: &mut [u8]) -> Result<usize> {
+	if let Some(ops) = &file.f_op {
+		// Create a UserSlicePtr from the buffer for the interface
+		let user_slice = unsafe { UserSlicePtr::new(buf.as_mut_ptr(), buf.len()) };
+		let result = ops.read(file, user_slice, buf.len())?;
+		Ok(result as usize)
+	} else {
+		Err(Error::ENOSYS)
+	}
+}
+
+/// Write to a file
+pub fn write_file(file: &Arc<File>, buf: &[u8]) -> Result<usize> {
+	if let Some(ops) = &file.f_op {
+		// Create a UserSlicePtr from the buffer for the interface
+		let user_slice = unsafe { UserSlicePtr::new(buf.as_ptr() as *mut u8, buf.len()) };
+		let result = ops.write(file, user_slice, buf.len())?;
+		Ok(result as usize)
+	} else {
+		Err(Error::ENOSYS)
+	}
+}
+
+/// Initialize VFS
+pub fn init_vfs() -> Result<()> {
+	// Initialize filesystems - just initialize the VFS, not individual filesystems
+	crate::info!("VFS initialized");
+	Ok(())
+}
+
+/// Open a file - Linux compatible sys_open
+pub fn open(pathname: &str, flags: i32, mode: u32) -> Result<i32> {
+	let mut vfs = VFS.lock();
+
+	// TODO: Path resolution, permission checks, etc.
+	// For now, create a simple file
+	let file = Arc::new(File::new(pathname, flags as u32, mode)?);
+	let fd = vfs.alloc_fd();
+	vfs.install_fd(fd, file);
+
+	Ok(fd)
+}
+
+/// Close a file descriptor - Linux compatible sys_close
+pub fn close(fd: i32) -> Result<()> {
+	let mut vfs = VFS.lock();
+	vfs.close_fd(fd)
+}
+
+/// Read from a file descriptor - Linux compatible sys_read
+pub fn read(fd: i32, buf: UserSlicePtr, count: usize) -> Result<isize> {
+	let vfs = VFS.lock();
+	let file = vfs.get_file(fd).ok_or(Error::EBADF)?;
+	drop(vfs);
+
+	file.read(buf, count)
+}
+
+/// Write to a file descriptor - Linux compatible sys_write
+pub fn write(fd: i32, buf: UserSlicePtr, count: usize) -> Result<isize> {
+	let vfs = VFS.lock();
+	let file = vfs.get_file(fd).ok_or(Error::EBADF)?;
+	drop(vfs);
+
+	file.write(buf, count)
+}
+
+/// Seek within a file - Linux compatible sys_lseek
+pub fn lseek(fd: i32, offset: i64, whence: i32) -> Result<i64> {
+	let vfs = VFS.lock();
+	let file = vfs.get_file(fd).ok_or(Error::EBADF)?;
+	drop(vfs);
+
+	file.seek(offset, whence)
+}
+
+/// Get file status - Linux compatible sys_fstat
+pub fn fstat(fd: i32, statbuf: UserPtr<KStat>) -> Result<()> {
+	let vfs = VFS.lock();
+	let file = vfs.get_file(fd).ok_or(Error::EBADF)?;
+	drop(vfs);
+
+	let stat = file.stat()?;
+	statbuf.write(stat)?;
+	Ok(())
+}
+
+/// Generic file operations for simple filesystems
+#[derive(Debug)]
+pub struct GenericFileOps;
+
+impl FileOperations for GenericFileOps {
+	fn read(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Default read implementation
+		Ok(0)
+	}
+
+	fn write(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Default write implementation
+		Ok(count as isize)
+	}
+
+	fn seek(&self, file: &File, offset: i64, whence: i32) -> Result<i64> {
+		// Default seek implementation
+		match whence {
+			SEEK_SET => Ok(offset),
+			SEEK_CUR => Ok(
+				file.pos.load(core::sync::atomic::Ordering::Relaxed) + offset
+			),
+			SEEK_END => Ok(offset), // TODO: Get file size
+			_ => Err(Error::EINVAL),
+		}
+	}
+
+	fn ioctl(&self, file: &File, cmd: u32, arg: usize) -> Result<isize> {
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, file: &File, vma: &mut crate::memory::VmaArea) -> Result<()> {
+		Err(Error::ENODEV)
+	}
+
+	fn fsync(&self, file: &File, datasync: bool) -> Result<()> {
+		Ok(())
+	}
+
+	fn poll(&self, file: &File, wait: &mut PollWait) -> Result<u32> {
+		Ok(POLLIN | POLLOUT)
+	}
+}
+
+/// Poll events
+pub const POLLIN: u32 = 0x001;
+pub const POLLPRI: u32 = 0x002;
+pub const POLLOUT: u32 = 0x004;
+pub const POLLERR: u32 = 0x008;
+pub const POLLHUP: u32 = 0x010;
+pub const POLLNVAL: u32 = 0x020;
+
+/// Poll wait structure (simplified)
+pub struct PollWait {
+	// TODO: Implement proper poll/select mechanism
+}
+
+impl PollWait {
+	pub fn new() -> Self {
+		Self {}
+	}
+}
+
+/// Global root filesystem
+static ROOT_FS: Mutex<Option<Arc<SuperBlock>>> = Mutex::new(None);
+
+/// Initialize root filesystem
+pub fn init_root_fs() -> Result<()> {
+	let ramfs_sb = ramfs::create_ramfs_superblock()?;
+	*ROOT_FS.lock() = Some(ramfs_sb);
+	Ok(())
+}
+
+/// Get root filesystem
+pub fn get_root_fs() -> Result<Arc<SuperBlock>> {
+	ROOT_FS.lock().clone().ok_or(Error::NotInitialized)
+}

kernel/src/fs/mode.rs

@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! File mode utilities - Linux compatible
+
+/// File mode constants (Linux compatible)
+pub const S_IFMT: u32 = 0o170000; // File type mask
+pub const S_IFSOCK: u32 = 0o140000; // Socket
+pub const S_IFLNK: u32 = 0o120000; // Symbolic link
+pub const S_IFREG: u32 = 0o100000; // Regular file
+pub const S_IFBLK: u32 = 0o060000; // Block device
+pub const S_IFDIR: u32 = 0o040000; // Directory
+pub const S_IFCHR: u32 = 0o020000; // Character device
+pub const S_IFIFO: u32 = 0o010000; // FIFO/pipe
+
+/// Permission bits
+pub const S_ISUID: u32 = 0o004000; // Set user ID
+pub const S_ISGID: u32 = 0o002000; // Set group ID
+pub const S_ISVTX: u32 = 0o001000; // Sticky bit
+
+/// User permissions
+pub const S_IRUSR: u32 = 0o000400; // Read by owner
+pub const S_IWUSR: u32 = 0o000200; // Write by owner
+pub const S_IXUSR: u32 = 0o000100; // Execute by owner
+
+/// Group permissions
+pub const S_IRGRP: u32 = 0o000040; // Read by group
+pub const S_IWGRP: u32 = 0o000020; // Write by group
+pub const S_IXGRP: u32 = 0o000010; // Execute by group
+
+/// Other permissions
+pub const S_IROTH: u32 = 0o000004; // Read by others
+pub const S_IWOTH: u32 = 0o000002; // Write by others
+pub const S_IXOTH: u32 = 0o000001; // Execute by others
+
+/// Linux stat utility functions
+pub fn s_isreg(mode: u32) -> bool {
+	(mode & S_IFMT) == S_IFREG
+}
+
+pub fn s_isdir(mode: u32) -> bool {
+	(mode & S_IFMT) == S_IFDIR
+}
+
+pub fn s_ischr(mode: u32) -> bool {
+	(mode & S_IFMT) == S_IFCHR
+}
+
+pub fn s_isblk(mode: u32) -> bool {
+	(mode & S_IFMT) == S_IFBLK
+}
+
+pub fn s_isfifo(mode: u32) -> bool {
+	(mode & S_IFMT) == S_IFIFO
+}
+
+pub fn s_islnk(mode: u32) -> bool {
+	(mode & S_IFMT) == S_IFLNK
+}
+
+pub fn s_issock(mode: u32) -> bool {
+	(mode & S_IFMT) == S_IFSOCK
+}
+
+/// Check if mode has execute permission for user
+pub fn s_ixusr(mode: u32) -> bool {
+	(mode & S_IXUSR) != 0
+}
+
+/// Check if mode has execute permission for group
+pub fn s_ixgrp(mode: u32) -> bool {
+	(mode & S_IXGRP) != 0
+}
+
+/// Check if mode has execute permission for others
+pub fn s_ixoth(mode: u32) -> bool {
+	(mode & S_IXOTH) != 0
+}
+
+/// Default file mode (0644)
+pub const DEFAULT_FILE_MODE: u32 = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
+
+/// Default directory mode (0755)
+pub const DEFAULT_DIR_MODE: u32 =
+	S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH;

kernel/src/fs/mount.rs

@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! VFS mount abstraction - Linux compatible
+
+use alloc::{format, string::String, vec::Vec}; // Add format macro
+use core::sync::atomic::{AtomicU32, Ordering};
+
+use crate::error::{Error, Result};
+use crate::sync::{Arc, Mutex};
+
+/// VFS mount structure - similar to Linux struct vfsmount
+#[derive(Debug)]
+pub struct VfsMount {
+	/// Mounted superblock
+	pub mnt_sb: Arc<super::SuperBlock>,
+	/// Mount point path
+	pub mnt_mountpoint: String,
+	/// Mount flags
+	pub mnt_flags: AtomicU32,
+	/// Parent mount
+	pub mnt_parent: Option<Arc<VfsMount>>,
+	/// Child mounts
+	pub mnt_children: Mutex<Vec<Arc<VfsMount>>>,
+	/// Reference count
+	pub mnt_count: AtomicU32,
+	/// Device name
+	pub mnt_devname: Option<String>,
+	/// Mount options
+	pub mnt_opts: Option<String>,
+}
+
+impl VfsMount {
+	/// Create a new VFS mount
+	pub fn new(sb: Arc<super::SuperBlock>, mountpoint: &str, flags: u32) -> Result<Self> {
+		Ok(Self {
+			mnt_sb: sb,
+			mnt_mountpoint: String::from(mountpoint),
+			mnt_flags: AtomicU32::new(flags),
+			mnt_parent: None,
+			mnt_children: Mutex::new(Vec::new()),
+			mnt_count: AtomicU32::new(1),
+			mnt_devname: None,
+			mnt_opts: None,
+		})
+	}
+
+	/// Set parent mount
+	pub fn set_parent(&mut self, parent: Arc<VfsMount>) {
+		self.mnt_parent = Some(parent);
+	}
+
+	/// Add child mount
+	pub fn add_child(&self, child: Arc<VfsMount>) {
+		let mut children = self.mnt_children.lock();
+		children.push(child);
+	}
+
+	/// Get mount flags
+	pub fn get_flags(&self) -> u32 {
+		self.mnt_flags.load(Ordering::Relaxed)
+	}
+
+	/// Check if mount is read-only
+	pub fn is_readonly(&self) -> bool {
+		(self.get_flags() & super::super_block::MS_RDONLY) != 0
+	}
+
+	/// Check if mount is nosuid
+	pub fn is_nosuid(&self) -> bool {
+		(self.get_flags() & super::super_block::MS_NOSUID) != 0
+	}
+
+	/// Check if mount is nodev
+	pub fn is_nodev(&self) -> bool {
+		(self.get_flags() & super::super_block::MS_NODEV) != 0
+	}
+
+	/// Check if mount is noexec
+	pub fn is_noexec(&self) -> bool {
+		(self.get_flags() & super::super_block::MS_NOEXEC) != 0
+	}
+
+	/// Increment reference count
+	pub fn mntget(&self) {
+		self.mnt_count.fetch_add(1, Ordering::Relaxed);
+	}
+
+	/// Decrement reference count
+	pub fn mntput(&self) {
+		let old_count = self.mnt_count.fetch_sub(1, Ordering::Relaxed);
+		if old_count == 1 {
+			// Last reference, mount should be cleaned up
+			// TODO: Unmount filesystem
+		}
+	}
+
+	/// Get full mount path
+	pub fn get_path(&self) -> String {
+		if let Some(ref parent) = self.mnt_parent {
+			if parent.mnt_mountpoint == "/" {
+				self.mnt_mountpoint.clone()
+			} else {
+				format!("{}{}", parent.get_path(), self.mnt_mountpoint)
+			}
+		} else {
+			self.mnt_mountpoint.clone()
+		}
+	}
+
+	/// Find child mount by path
+	pub fn find_child_mount(&self, path: &str) -> Option<Arc<VfsMount>> {
+		let children = self.mnt_children.lock();
+		for child in children.iter() {
+			if child.mnt_mountpoint == path {
+				return Some(child.clone());
+			}
+		}
+		None
+	}
+}
+
+unsafe impl Send for VfsMount {}
+unsafe impl Sync for VfsMount {}
+
+/// Mount namespace - similar to Linux struct mnt_namespace
+pub struct MountNamespace {
+	/// Root mount
+	pub root: Option<Arc<VfsMount>>,
+	/// All mounts in this namespace
+	pub mounts: Mutex<Vec<Arc<VfsMount>>>,
+	/// Namespace ID
+	pub ns_id: u64,
+	/// Reference count
+	pub count: AtomicU32,
+}
+
+impl MountNamespace {
+	/// Create a new mount namespace
+	pub fn new(ns_id: u64) -> Self {
+		Self {
+			root: None,
+			mounts: Mutex::new(Vec::new()),
+			ns_id,
+			count: AtomicU32::new(1),
+		}
+	}
+
+	/// Add mount to namespace
+	pub fn add_mount(&self, mount: Arc<VfsMount>) {
+		let mut mounts = self.mounts.lock();
+		mounts.push(mount);
+	}
+
+	/// Remove mount from namespace
+	pub fn remove_mount(&self, mountpoint: &str) -> Option<Arc<VfsMount>> {
+		let mut mounts = self.mounts.lock();
+		if let Some(pos) = mounts.iter().position(|m| m.mnt_mountpoint == mountpoint) {
+			Some(mounts.remove(pos))
+		} else {
+			None
+		}
+	}
+
+	/// Find mount by path
+	pub fn find_mount(&self, path: &str) -> Option<Arc<VfsMount>> {
+		let mounts = self.mounts.lock();
+
+		// Find the longest matching mount point
+		let mut best_match: Option<Arc<VfsMount>> = None;
+		let mut best_len = 0;
+
+		for mount in mounts.iter() {
+			let mount_path = mount.get_path();
+			if path.starts_with(&mount_path) && mount_path.len() > best_len {
+				best_match = Some(mount.clone());
+				best_len = mount_path.len();
+			}
+		}
+
+		best_match
+	}
+
+	/// Get all mount points
+	pub fn get_mount_points(&self) -> Vec<String> {
+		let mounts = self.mounts.lock();
+		mounts.iter().map(|m| m.get_path()).collect()
+	}
+
+	/// Set root mount
+	pub fn set_root(&mut self, root: Arc<VfsMount>) {
+		self.root = Some(root.clone());
+		self.add_mount(root);
+	}
+}
+
+/// Global mount namespace
+static INIT_MNT_NS: spin::once::Once<Mutex<MountNamespace>> = spin::once::Once::new();
+
+fn get_init_mnt_ns() -> &'static Mutex<MountNamespace> {
+	INIT_MNT_NS.call_once(|| Mutex::new(MountNamespace::new(1)))
+}
+
+/// Get the init mount namespace
+pub fn get_init_ns() -> &'static Mutex<MountNamespace> {
+	get_init_mnt_ns()
+}
+
+/// Mount a filesystem
+pub fn do_mount(
+	dev_name: &str,
+	dir_name: &str,
+	type_name: &str,
+	flags: u32,
+	data: Option<&str>,
+) -> Result<()> {
+	// TODO: Look up filesystem type
+	// For now, create a basic mount
+	let sb = Arc::new(super::SuperBlock::new(type_name)?);
+	let mount = Arc::new(VfsMount::new(sb, dir_name, flags)?);
+
+	let ns = get_init_ns();
+	let ns = ns.lock();
+	ns.add_mount(mount);
+
+	crate::console::print_info(&format!(
+		"Mounted {} on {} (type {})\n",
+		dev_name, dir_name, type_name
+	));
+	Ok(())
+}
+
+/// Unmount a filesystem
+pub fn do_umount(dir_name: &str, flags: u32) -> Result<()> {
+	let ns = get_init_ns();
+	let ns = ns.lock();
+
+	if let Some(mount) = ns.remove_mount(dir_name) {
+		mount.mntput();
+		crate::console::print_info(&format!("Unmounted {}\n", dir_name));
+		Ok(())
+	} else {
+		Err(Error::ENOENT)
+	}
+}
+
+/// Get mount information for a path
+pub fn path_get_mount(path: &str) -> Option<Arc<VfsMount>> {
+	let ns = get_init_ns();
+	let ns = ns.lock();
+	ns.find_mount(path)
+}
+
+/// Check if a path is a mount point
+pub fn is_mountpoint(path: &str) -> bool {
+	let ns = get_init_ns();
+	let ns = ns.lock();
+	let mounts = ns.mounts.lock();
+	mounts.iter().any(|m| m.get_path() == path)
+}
+
+/// Get all mount points
+pub fn get_all_mounts() -> Vec<String> {
+	let ns = get_init_ns();
+	let ns = ns.lock();
+	ns.get_mount_points()
+}
+
+/// Remount a filesystem with new flags
+pub fn do_remount(dir_name: &str, flags: u32, data: Option<&str>) -> Result<()> {
+	let ns = get_init_ns();
+	let ns = ns.lock();
+
+	if let Some(mount) = ns.find_mount(dir_name) {
+		mount.mnt_flags.store(flags, Ordering::Relaxed);
+
+		// Also remount the superblock
+		if let Some(ref ops) = mount.mnt_sb.s_op {
+			ops.remount_fs(&mount.mnt_sb, flags, data)?;
+		}
+
+		crate::console::print_info(&format!(
+			"Remounted {} with flags {:#x}\n",
+			dir_name, flags
+		));
+		Ok(())
+	} else {
+		Err(Error::ENOENT)
+	}
+}
+
+/// Bind mount - create a bind mount
+pub fn do_bind_mount(old_path: &str, new_path: &str, flags: u32) -> Result<()> {
+	let ns = get_init_ns();
+	let ns = ns.lock();
+
+	if let Some(old_mount) = ns.find_mount(old_path) {
+		let new_mount = Arc::new(VfsMount::new(
+			old_mount.mnt_sb.clone(),
+			new_path,
+			flags | super::super_block::MS_BIND,
+		)?);
+		ns.add_mount(new_mount);
+
+		crate::console::print_info(&format!("Bind mounted {} to {}\n", old_path, new_path));
+		Ok(())
+	} else {
+		Err(Error::ENOENT)
+	}
+}

kernel/src/fs/operations.rs

@@ -0,0 +1,446 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Various VFS operations and utilities
+
+use crate::error::{Error, Result};
+use crate::memory::UserSlicePtr;
+use crate::sync::Arc;
+
+/// Address space operations trait - similar to Linux address_space_operations
+pub trait AddressSpaceOperations: Send + Sync {
+	/// Write a page
+	fn writepage(&self, page: &crate::memory::Page) -> Result<()>;
+
+	/// Read a page
+	fn readpage(&self, file: Option<&super::File>, page: &crate::memory::Page) -> Result<()>;
+
+	/// Sync pages
+	fn sync_page(&self, page: &crate::memory::Page) -> Result<()>;
+
+	/// Write pages
+	fn writepages(&self, mapping: &AddressSpace, wbc: &WritebackControl) -> Result<()>;
+
+	/// Set page dirty
+	fn set_page_dirty(&self, page: &crate::memory::Page) -> Result<bool>;
+
+	/// Read pages ahead
+	fn readpages(
+		&self,
+		file: Option<&super::File>,
+		pages: &[&crate::memory::Page],
+	) -> Result<()>;
+
+	/// Write begin
+	fn write_begin(&self, file: &super::File, pos: u64, len: u32) -> Result<()>;
+
+	/// Write end
+	fn write_end(&self, file: &super::File, pos: u64, len: u32, copied: u32) -> Result<u32>;
+
+	/// Direct I/O
+	fn direct_io(
+		&self,
+		file: &super::File,
+		pos: u64,
+		buf: UserSlicePtr,
+		len: usize,
+		write: bool,
+	) -> Result<isize>;
+}
+
+/// Address space structure
+pub struct AddressSpace {
+	/// Host inode
+	pub host: Option<Arc<super::Inode>>,
+	/// Address space operations
+	pub a_ops: Option<Arc<dyn AddressSpaceOperations>>,
+	/// Number of pages
+	pub nrpages: core::sync::atomic::AtomicUsize,
+	/// Flags
+	pub flags: core::sync::atomic::AtomicU32,
+	/// Private data
+	pub private_data: Option<*mut u8>,
+}
+
+impl AddressSpace {
+	pub fn new() -> Self {
+		Self {
+			host: None,
+			a_ops: None,
+			nrpages: core::sync::atomic::AtomicUsize::new(0),
+			flags: core::sync::atomic::AtomicU32::new(0),
+			private_data: None,
+		}
+	}
+}
+
+/// Writeback control structure
+pub struct WritebackControl {
+	pub start: u64,
+	pub end: u64,
+	pub sync_mode: WritebackSyncMode,
+	pub nr_to_write: u64,
+	pub tagged_writepages: bool,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum WritebackSyncMode {
+	None,
+	All,
+	Memory,
+}
+
+/// Generic file operations implementation
+#[derive(Debug)]
+pub struct GenericFileOperations;
+
+impl super::FileOperations for GenericFileOperations {
+	fn read(&self, file: &super::File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Generic read implementation using page cache
+		// TODO: Implement proper page cache read
+		Ok(0)
+	}
+
+	fn write(&self, file: &super::File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Generic write implementation using page cache
+		// TODO: Implement proper page cache write
+		Ok(count as isize)
+	}
+
+	fn seek(&self, file: &super::File, offset: i64, whence: i32) -> Result<i64> {
+		let current_pos = file.get_pos();
+		let new_pos = match whence {
+			super::SEEK_SET => offset,
+			super::SEEK_CUR => current_pos + offset,
+			super::SEEK_END => {
+				// Get file size from inode
+				if let Some(ref inode) = file.inode {
+					inode.get_size() as i64 + offset
+				} else {
+					offset
+				}
+			}
+			_ => return Err(Error::EINVAL),
+		};
+
+		if new_pos < 0 {
+			return Err(Error::EINVAL);
+		}
+
+		file.set_pos(new_pos);
+		Ok(new_pos)
+	}
+
+	fn ioctl(&self, file: &super::File, cmd: u32, arg: usize) -> Result<isize> {
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, file: &super::File, vma: &mut crate::memory::VmaArea) -> Result<()> {
+		// Generic mmap implementation
+		// TODO: Implement proper memory mapping
+		Err(Error::ENODEV)
+	}
+
+	fn fsync(&self, file: &super::File, datasync: bool) -> Result<()> {
+		// Sync file data to storage
+		if let Some(ref inode) = file.inode {
+			// TODO: Sync inode and data blocks
+		}
+		Ok(())
+	}
+
+	fn poll(&self, file: &super::File, wait: &mut super::PollWait) -> Result<u32> {
+		// Regular files are always ready for I/O
+		Ok(super::POLLIN | super::POLLOUT)
+	}
+
+	fn readdir(&self, file: &super::File, ctx: &mut super::file::DirContext) -> Result<()> {
+		// This shouldn't be called for regular files
+		Err(Error::ENOTDIR)
+	}
+}
+
+/// Directory file operations
+#[derive(Debug)]
+pub struct DirectoryOperations;
+
+impl super::FileOperations for DirectoryOperations {
+	fn read(&self, file: &super::File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Can't read directory as regular file
+		Err(Error::EISDIR)
+	}
+
+	fn write(&self, file: &super::File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Can't write to directory as regular file
+		Err(Error::EISDIR)
+	}
+
+	fn seek(&self, file: &super::File, offset: i64, whence: i32) -> Result<i64> {
+		// Directory seeking
+		match whence {
+			super::SEEK_SET => {
+				if offset < 0 {
+					return Err(Error::EINVAL);
+				}
+				file.set_pos(offset);
+				Ok(offset)
+			}
+			super::SEEK_CUR => {
+				let new_pos = file.get_pos() + offset;
+				if new_pos < 0 {
+					return Err(Error::EINVAL);
+				}
+				file.set_pos(new_pos);
+				Ok(new_pos)
+			}
+			super::SEEK_END => {
+				// Seek to end of directory
+				file.set_pos(i64::MAX);
+				Ok(i64::MAX)
+			}
+			_ => Err(Error::EINVAL),
+		}
+	}
+
+	fn ioctl(&self, file: &super::File, cmd: u32, arg: usize) -> Result<isize> {
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, file: &super::File, vma: &mut crate::memory::VmaArea) -> Result<()> {
+		Err(Error::ENODEV)
+	}
+
+	fn fsync(&self, file: &super::File, datasync: bool) -> Result<()> {
+		// Sync directory
+		Ok(())
+	}
+
+	fn poll(&self, file: &super::File, wait: &mut super::PollWait) -> Result<u32> {
+		// Directories are always ready
+		Ok(super::POLLIN)
+	}
+
+	fn readdir(&self, file: &super::File, ctx: &mut super::file::DirContext) -> Result<()> {
+		// Read directory entries
+		if let Some(ref inode) = file.inode {
+			if let Some(ref dentry) = file.dentry {
+				let subdirs = dentry.d_subdirs.lock();
+				for (i, child) in subdirs.iter().enumerate() {
+					if i >= ctx.pos as usize {
+						let d_type = if let Some(ref child_inode) =
+							child.d_inode
+						{
+							let mode = child_inode.i_mode.load(core::sync::atomic::Ordering::Relaxed);
+							if super::mode::s_isdir(mode) {
+								super::DT_DIR
+							} else if super::mode::s_isreg(mode) {
+								super::DT_REG
+							} else if super::mode::s_islnk(mode) {
+								super::DT_LNK
+							} else if super::mode::s_ischr(mode) {
+								super::DT_CHR
+							} else if super::mode::s_isblk(mode) {
+								super::DT_BLK
+							} else if super::mode::s_isfifo(mode) {
+								super::DT_FIFO
+							} else if super::mode::s_issock(mode) {
+								super::DT_SOCK
+							} else {
+								super::DT_UNKNOWN
+							}
+						} else {
+							super::DT_UNKNOWN
+						};
+
+						let ino = if let Some(ref child_inode) =
+							child.d_inode
+						{
+							child_inode.i_ino
+						} else {
+							0
+						};
+
+						ctx.add_entry(ino, &child.d_name, d_type);
+					}
+				}
+			}
+		}
+		Ok(())
+	}
+}
+
+/// Special file operations (for device files)
+#[derive(Debug)]
+pub struct SpecialFileOperations;
+
+impl super::FileOperations for SpecialFileOperations {
+	fn read(&self, file: &super::File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Delegate to device driver
+		if let Some(ref inode) = file.inode {
+			if inode.is_char_device() || inode.is_block_device() {
+				// TODO: Call device driver read function
+				return Ok(0);
+			}
+		}
+		Err(Error::ENODEV)
+	}
+
+	fn write(&self, file: &super::File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		// Delegate to device driver
+		if let Some(ref inode) = file.inode {
+			if inode.is_char_device() || inode.is_block_device() {
+				// TODO: Call device driver write function
+				return Ok(count as isize);
+			}
+		}
+		Err(Error::ENODEV)
+	}
+
+	fn seek(&self, file: &super::File, offset: i64, whence: i32) -> Result<i64> {
+		// Most device files don't support seeking
+		Err(Error::ESPIPE)
+	}
+
+	fn ioctl(&self, file: &super::File, cmd: u32, arg: usize) -> Result<isize> {
+		// Delegate to device driver
+		if let Some(ref inode) = file.inode {
+			if inode.is_char_device() || inode.is_block_device() {
+				// TODO: Call device driver ioctl function
+				return Ok(0);
+			}
+		}
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, file: &super::File, vma: &mut crate::memory::VmaArea) -> Result<()> {
+		// Some device files support mmap
+		Err(Error::ENODEV)
+	}
+
+	fn fsync(&self, file: &super::File, datasync: bool) -> Result<()> {
+		// Nothing to sync for device files
+		Ok(())
+	}
+
+	fn poll(&self, file: &super::File, wait: &mut super::PollWait) -> Result<u32> {
+		// Delegate to device driver
+		if let Some(ref inode) = file.inode {
+			if inode.is_char_device() {
+				// TODO: Call device driver poll function
+				return Ok(super::POLLIN | super::POLLOUT);
+			}
+		}
+		Ok(0)
+	}
+}
+
+/// No-op address space operations
+pub struct NoOpAddressSpaceOps;
+
+impl AddressSpaceOperations for NoOpAddressSpaceOps {
+	fn writepage(&self, page: &crate::memory::Page) -> Result<()> {
+		Ok(())
+	}
+
+	fn readpage(&self, file: Option<&super::File>, page: &crate::memory::Page) -> Result<()> {
+		Ok(())
+	}
+
+	fn sync_page(&self, page: &crate::memory::Page) -> Result<()> {
+		Ok(())
+	}
+
+	fn writepages(&self, mapping: &AddressSpace, wbc: &WritebackControl) -> Result<()> {
+		Ok(())
+	}
+
+	fn set_page_dirty(&self, page: &crate::memory::Page) -> Result<bool> {
+		Ok(true)
+	}
+
+	fn readpages(
+		&self,
+		file: Option<&super::File>,
+		pages: &[&crate::memory::Page],
+	) -> Result<()> {
+		Ok(())
+	}
+
+	fn write_begin(&self, file: &super::File, pos: u64, len: u32) -> Result<()> {
+		Ok(())
+	}
+
+	fn write_end(&self, file: &super::File, pos: u64, len: u32, copied: u32) -> Result<u32> {
+		Ok(copied)
+	}
+
+	fn direct_io(
+		&self,
+		file: &super::File,
+		pos: u64,
+		buf: UserSlicePtr,
+		len: usize,
+		write: bool,
+	) -> Result<isize> {
+		if write {
+			Ok(len as isize)
+		} else {
+			Ok(0)
+		}
+	}
+}
+
+/// Helper functions for VFS operations
+
+/// Get file operations for an inode
+pub fn get_file_operations(inode: &super::Inode) -> Arc<dyn super::FileOperations> {
+	if let Some(ref fop) = inode.i_fop {
+		fop.clone()
+	} else {
+		let mode = inode.i_mode.load(core::sync::atomic::Ordering::Relaxed);
+		if super::mode::s_isreg(mode) {
+			Arc::new(GenericFileOperations)
+		} else if super::mode::s_isdir(mode) {
+			Arc::new(DirectoryOperations)
+		} else if super::mode::s_ischr(mode) || super::mode::s_isblk(mode) {
+			Arc::new(SpecialFileOperations)
+		} else {
+			Arc::new(super::GenericFileOps)
+		}
+	}
+}
+
+/// Check file permissions
+pub fn check_permissions(inode: &super::Inode, mask: u32) -> Result<()> {
+	// TODO: Implement proper permission checking
+	// For now, allow all operations
+	Ok(())
+}
+
+/// Update access time
+pub fn update_atime(inode: &super::Inode) {
+	inode.update_atime();
+}
+
+/// Update modification time
+pub fn update_mtime(inode: &super::Inode) {
+	inode.update_mtime();
+}
+
+/// Truncate file to specified size
+pub fn do_truncate(inode: &super::Inode, size: u64) -> Result<()> {
+	if let Some(ref ops) = inode.i_op {
+		ops.truncate(inode, size)
+	} else {
+		inode.set_size(size);
+		Ok(())
+	}
+}
+
+/// Notify directory change
+pub fn notify_change(inode: &super::Inode, attr: &super::inode::InodeAttr) -> Result<()> {
+	if let Some(ref ops) = inode.i_op {
+		ops.setattr(inode, attr)
+	} else {
+		Ok(())
+	}
+}

kernel/src/fs/path.rs

@@ -0,0 +1,394 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Path resolution and manipulation - Linux compatible
+
+use alloc::{
+	format,
+	string::{String, ToString},
+	vec::Vec,
+};
+
+use crate::error::{Error, Result};
+use crate::sync::Arc; // Add format macro and ToString
+
+/// Path structure for path resolution
+#[derive(Debug, Clone)]
+pub struct Path {
+	/// Mount point
+	pub mnt: Option<Arc<super::VfsMount>>,
+	/// Dentry
+	pub dentry: Option<Arc<super::Dentry>>,
+}
+
+impl Path {
+	/// Create a new path
+	pub fn new() -> Self {
+		Self {
+			mnt: None,
+			dentry: None,
+		}
+	}
+
+	/// Create path from mount and dentry
+	pub fn from_mount_dentry(mnt: Arc<super::VfsMount>, dentry: Arc<super::Dentry>) -> Self {
+		Self {
+			mnt: Some(mnt),
+			dentry: Some(dentry),
+		}
+	}
+
+	/// Get the full path string
+	pub fn to_string(&self) -> String {
+		if let Some(ref dentry) = self.dentry {
+			dentry.get_path()
+		} else {
+			String::from("/")
+		}
+	}
+
+	/// Check if path is absolute
+	pub fn is_absolute(&self) -> bool {
+		self.to_string().starts_with('/')
+	}
+
+	/// Get parent path
+	pub fn parent(&self) -> Option<Path> {
+		if let Some(ref dentry) = self.dentry {
+			if let Some(ref parent) = dentry.d_parent {
+				Some(Path {
+					mnt: self.mnt.clone(),
+					dentry: Some(parent.clone()),
+				})
+			} else {
+				None
+			}
+		} else {
+			None
+		}
+	}
+
+	/// Get filename component
+	pub fn filename(&self) -> Option<String> {
+		if let Some(ref dentry) = self.dentry {
+			Some(dentry.d_name.clone())
+		} else {
+			None
+		}
+	}
+
+	/// Join with another path component
+	pub fn join(&self, component: &str) -> Result<Path> {
+		if let Some(ref dentry) = self.dentry {
+			if let Some(child) = dentry.find_child(component) {
+				Ok(Path {
+					mnt: self.mnt.clone(),
+					dentry: Some(child),
+				})
+			} else {
+				Err(Error::ENOENT)
+			}
+		} else {
+			Err(Error::ENOENT)
+		}
+	}
+}
+
+/// Path lookup flags
+pub const LOOKUP_FOLLOW: u32 = 0x0001;
+pub const LOOKUP_DIRECTORY: u32 = 0x0002;
+pub const LOOKUP_AUTOMOUNT: u32 = 0x0004;
+pub const LOOKUP_EMPTY: u32 = 0x0008;
+pub const LOOKUP_OPEN: u32 = 0x0010;
+pub const LOOKUP_CREATE: u32 = 0x0020;
+pub const LOOKUP_EXCL: u32 = 0x0040;
+pub const LOOKUP_RENAME_TARGET: u32 = 0x0080;
+
+/// Name data structure for path resolution
+pub struct NameData {
+	/// Path components
+	pub path: String,
+	/// Current position in path
+	pub pos: usize,
+	/// Lookup flags
+	pub flags: u32,
+	/// Root directory
+	pub root: Option<Path>,
+	/// Current working directory
+	pub pwd: Option<Path>,
+	/// Result path
+	pub result: Option<Path>,
+	/// Intent (for create/open operations)
+	pub intent: Option<Intent>,
+}
+
+/// Intent for path operations
+#[derive(Debug, Clone)]
+pub enum Intent {
+	Open { flags: u32, mode: u32 },
+	Create { mode: u32 },
+	Lookup,
+}
+
+impl NameData {
+	/// Create new name data for path resolution
+	pub fn new(path: String, flags: u32) -> Self {
+		Self {
+			path,
+			pos: 0,
+			flags,
+			root: None,
+			pwd: None,
+			result: None,
+			intent: None,
+		}
+	}
+
+	/// Set root directory
+	pub fn with_root(mut self, root: Path) -> Self {
+		self.root = Some(root);
+		self
+	}
+
+	/// Set current working directory
+	pub fn with_pwd(mut self, pwd: Path) -> Self {
+		self.pwd = Some(pwd);
+		self
+	}
+
+	/// Set intent
+	pub fn with_intent(mut self, intent: Intent) -> Self {
+		self.intent = Some(intent);
+		self
+	}
+
+	/// Get next path component
+	pub fn next_component(&mut self) -> Option<String> {
+		if self.pos >= self.path.len() {
+			return None;
+		}
+
+		// Skip leading slashes
+		while self.pos < self.path.len() && self.path.chars().nth(self.pos) == Some('/') {
+			self.pos += 1;
+		}
+
+		if self.pos >= self.path.len() {
+			return None;
+		}
+
+		// Find end of component
+		let start = self.pos;
+		while self.pos < self.path.len() && self.path.chars().nth(self.pos) != Some('/') {
+			self.pos += 1;
+		}
+
+		Some(self.path[start..self.pos].to_string())
+	}
+
+	/// Check if path is finished
+	pub fn is_finished(&self) -> bool {
+		self.pos >= self.path.len()
+	}
+}
+
+/// Resolve a path to a dentry
+pub fn path_lookup(pathname: &str, flags: u32) -> Result<Path> {
+	let mut nd = NameData::new(String::from(pathname), flags);
+
+	// Set root directory (for now, use a dummy root)
+	// TODO: Get actual root from current process
+
+	// Start from root or current directory
+	let mut current_path = if pathname.starts_with('/') {
+		// Absolute path - start from root
+		if let Some(root) = nd.root.clone() {
+			root
+		} else {
+			// Create dummy root path
+			Path::new()
+		}
+	} else {
+		// Relative path - start from current directory
+		if let Some(pwd) = nd.pwd.clone() {
+			pwd
+		} else {
+			// Create dummy current directory
+			Path::new()
+		}
+	};
+
+	// Resolve each component
+	while let Some(component) = nd.next_component() {
+		match component.as_str() {
+			"." => {
+				// Current directory - no change
+				continue;
+			}
+			".." => {
+				// Parent directory
+				if let Some(parent) = current_path.parent() {
+					current_path = parent;
+				}
+				continue;
+			}
+			_ => {
+				// Regular component
+				current_path = current_path.join(&component)?;
+			}
+		}
+
+		// Check for mount points
+		if let Some(mount) = super::mount::path_get_mount(&current_path.to_string()) {
+			current_path.mnt = Some(mount);
+		}
+
+		// Handle symlinks if LOOKUP_FOLLOW is set
+		if (flags & LOOKUP_FOLLOW) != 0 {
+			if let Some(ref dentry) = current_path.dentry {
+				if let Some(ref inode) = dentry.d_inode {
+					if super::mode::s_islnk(
+						inode.i_mode.load(
+							core::sync::atomic::Ordering::Relaxed,
+						),
+					) {
+						// TODO: Follow symbolic link
+						// For now, just continue
+					}
+				}
+			}
+		}
+	}
+
+	nd.result = Some(current_path.clone());
+	Ok(current_path)
+}
+
+/// Resolve parent directory and filename
+pub fn path_parent_and_name(pathname: &str) -> Result<(Path, String)> {
+	let path = Path::new();
+
+	// Split pathname into parent and filename
+	if let Some(last_slash) = pathname.rfind('/') {
+		let parent_path = &pathname[..last_slash];
+		let filename = &pathname[last_slash + 1..];
+
+		if parent_path.is_empty() {
+			// Root directory
+			Ok((path, String::from(filename)))
+		} else {
+			let parent = path_lookup(parent_path, 0)?;
+			Ok((parent, String::from(filename)))
+		}
+	} else {
+		// No slash - filename in current directory
+		Ok((path, String::from(pathname)))
+	}
+}
+
+/// Normalize a path (remove . and .. components)
+pub fn normalize_path(path: &str) -> String {
+	let mut components = Vec::new();
+
+	for component in path.split('/') {
+		match component {
+			"" | "." => {
+				// Skip empty and current directory components
+				continue;
+			}
+			".." => {
+				// Parent directory - remove last component
+				components.pop();
+			}
+			_ => {
+				// Regular component
+				components.push(component);
+			}
+		}
+	}
+
+	let result = components.join("/");
+	if path.starts_with('/') {
+		format!("/{}", result)
+	} else {
+		result
+	}
+}
+
+/// Check if a path is safe (no .. escapes)
+pub fn is_safe_path(path: &str) -> bool {
+	let normalized = normalize_path(path);
+
+	// Check for .. at the beginning
+	if normalized.starts_with("..") {
+		return false;
+	}
+
+	// Check for /../ sequences
+	if normalized.contains("/../") {
+		return false;
+	}
+
+	true
+}
+
+/// Join two paths
+pub fn join_paths(base: &str, path: &str) -> String {
+	if path.starts_with('/') {
+		// Absolute path
+		String::from(path)
+	} else {
+		// Relative path
+		let base = base.trim_end_matches('/');
+		if base.is_empty() {
+			format!("/{}", path)
+		} else {
+			format!("{}/{}", base, path)
+		}
+	}
+}
+
+/// Get the directory part of a path
+pub fn dirname(path: &str) -> &str {
+	if let Some(last_slash) = path.rfind('/') {
+		if last_slash == 0 {
+			"/"
+		} else {
+			&path[..last_slash]
+		}
+	} else {
+		"."
+	}
+}
+
+/// Get the filename part of a path
+pub fn basename(path: &str) -> &str {
+	if let Some(last_slash) = path.rfind('/') {
+		&path[last_slash + 1..]
+	} else {
+		path
+	}
+}
+
+/// Get file extension
+pub fn extension(path: &str) -> Option<&str> {
+	let filename = basename(path);
+	if let Some(last_dot) = filename.rfind('.') {
+		if last_dot > 0 {
+			Some(&filename[last_dot + 1..])
+		} else {
+			None
+		}
+	} else {
+		None
+	}
+}
+
+/// Check if path is absolute
+pub fn is_absolute(path: &str) -> bool {
+	path.starts_with('/')
+}
+
+/// Check if path is relative
+pub fn is_relative(path: &str) -> bool {
+	!is_absolute(path)
+}

kernel/src/fs/procfs.rs

@@ -0,0 +1,503 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Proc filesystem implementation - Linux compatible
+
+use alloc::{boxed::Box, collections::BTreeMap, format, string::String, vec, vec::Vec}; /* Add vec macro and Box */
+use core::sync::atomic::{AtomicU64, Ordering};
+
+use crate::error::{Error, Result};
+use crate::fs::*;
+use crate::memory::UserSlicePtr;
+use crate::sync::{Arc, Mutex};
+
+/// Proc filesystem entry
+#[derive(Debug)]
+pub struct ProcEntry {
+	/// Entry name
+	pub name: String,
+	/// Entry type
+	pub entry_type: ProcEntryType,
+	/// Mode
+	pub mode: u32,
+	/// Read function
+	pub read: Option<fn(&ProcEntry, &mut String) -> Result<()>>,
+	/// Write function
+	pub write: Option<fn(&ProcEntry, &str) -> Result<()>>,
+	/// Child entries (for directories)
+	pub children: Mutex<Vec<Arc<ProcEntry>>>,
+	/// Parent entry
+	pub parent: Option<Arc<ProcEntry>>,
+	/// Private data
+	pub private_data: Option<*mut u8>,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum ProcEntryType {
+	File,
+	Directory,
+	Symlink,
+}
+
+impl ProcEntry {
+	pub fn new_file(
+		name: String,
+		mode: u32,
+		read_fn: fn(&ProcEntry, &mut String) -> Result<()>,
+	) -> Self {
+		Self {
+			name,
+			entry_type: ProcEntryType::File,
+			mode,
+			read: Some(read_fn),
+			write: None,
+			children: Mutex::new(Vec::new()),
+			parent: None,
+			private_data: None,
+		}
+	}
+
+	pub fn new_dir(name: String, mode: u32) -> Self {
+		Self {
+			name,
+			entry_type: ProcEntryType::Directory,
+			mode,
+			read: None,
+			write: None,
+			children: Mutex::new(Vec::new()),
+			parent: None,
+			private_data: None,
+		}
+	}
+
+	pub fn add_child(self: &Arc<Self>, child: Arc<ProcEntry>) {
+		let mut children = self.children.lock();
+		children.push(child);
+	}
+
+	pub fn find_child(&self, name: &str) -> Option<Arc<ProcEntry>> {
+		let children = self.children.lock();
+		for child in children.iter() {
+			if child.name == name {
+				return Some(child.clone());
+			}
+		}
+		None
+	}
+}
+
+unsafe impl Send for ProcEntry {}
+unsafe impl Sync for ProcEntry {}
+
+/// Proc filesystem
+pub struct ProcFs {
+	/// Root entry
+	pub root: Arc<ProcEntry>,
+	/// Next inode number
+	next_ino: AtomicU64,
+	/// Entry to inode mapping
+	entries: Mutex<BTreeMap<*const ProcEntry, u64>>,
+}
+
+impl ProcFs {
+	pub fn new() -> Self {
+		let root = Arc::new(ProcEntry::new_dir(String::from("proc"), 0o755));
+		let mut fs = Self {
+			root,
+			next_ino: AtomicU64::new(1),
+			entries: Mutex::new(BTreeMap::new()),
+		};
+
+		fs.create_default_entries();
+		fs
+	}
+
+	fn alloc_ino(&self) -> u64 {
+		self.next_ino.fetch_add(1, Ordering::Relaxed)
+	}
+
+	fn get_or_create_ino(&self, entry: &ProcEntry) -> u64 {
+		let entry_ptr = entry as *const ProcEntry;
+		let mut entries = self.entries.lock();
+
+		if let Some(&ino) = entries.get(&entry_ptr) {
+			ino
+		} else {
+			let ino = self.alloc_ino();
+			entries.insert(entry_ptr, ino);
+			ino
+		}
+	}
+
+	fn create_default_entries(&mut self) {
+		// Create /proc/version
+		let version_entry = Arc::new(ProcEntry::new_file(
+			String::from("version"),
+			0o444,
+			proc_version_read,
+		));
+		self.root.add_child(version_entry);
+
+		// Create /proc/meminfo
+		let meminfo_entry = Arc::new(ProcEntry::new_file(
+			String::from("meminfo"),
+			0o444,
+			proc_meminfo_read,
+		));
+		self.root.add_child(meminfo_entry);
+
+		// Create /proc/cpuinfo
+		let cpuinfo_entry = Arc::new(ProcEntry::new_file(
+			String::from("cpuinfo"),
+			0o444,
+			proc_cpuinfo_read,
+		));
+		self.root.add_child(cpuinfo_entry);
+
+		// Create /proc/uptime
+		let uptime_entry = Arc::new(ProcEntry::new_file(
+			String::from("uptime"),
+			0o444,
+			proc_uptime_read,
+		));
+		self.root.add_child(uptime_entry);
+
+		// Create /proc/loadavg
+		let loadavg_entry = Arc::new(ProcEntry::new_file(
+			String::from("loadavg"),
+			0o444,
+			proc_loadavg_read,
+		));
+		self.root.add_child(loadavg_entry);
+
+		// Create /proc/stat
+		let stat_entry = Arc::new(ProcEntry::new_file(
+			String::from("stat"),
+			0o444,
+			proc_stat_read,
+		));
+		self.root.add_child(stat_entry);
+
+		// Create /proc/mounts
+		let mounts_entry = Arc::new(ProcEntry::new_file(
+			String::from("mounts"),
+			0o444,
+			proc_mounts_read,
+		));
+		self.root.add_child(mounts_entry);
+	}
+}
+
+/// Proc filesystem file operations
+#[derive(Debug)]
+pub struct ProcFileOps {
+	entry: Arc<ProcEntry>,
+}
+
+impl ProcFileOps {
+	pub fn new(entry: Arc<ProcEntry>) -> Self {
+		Self { entry }
+	}
+}
+
+impl FileOperations for ProcFileOps {
+	fn read(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		match self.entry.entry_type {
+			ProcEntryType::File => {
+				if let Some(read_fn) = self.entry.read {
+					let mut content = String::new();
+					read_fn(&self.entry, &mut content)?;
+
+					let pos = file.get_pos() as usize;
+					if pos >= content.len() {
+						return Ok(0);
+					}
+
+					let to_copy = core::cmp::min(count, content.len() - pos);
+					let data = &content.as_bytes()[pos..pos + to_copy];
+
+					buf.copy_from_slice(data)?;
+					file.set_pos(file.get_pos() + to_copy as i64);
+
+					Ok(to_copy as isize)
+				} else {
+					Ok(0)
+				}
+			}
+			_ => Err(Error::EISDIR),
+		}
+	}
+
+	fn write(&self, file: &File, buf: UserSlicePtr, count: usize) -> Result<isize> {
+		if let Some(write_fn) = self.entry.write {
+			let mut data = vec![0u8; count];
+			buf.copy_to_slice(&mut data)?;
+			let content = String::from_utf8(data).map_err(|_| Error::EINVAL)?;
+			write_fn(&self.entry, &content)?;
+			Ok(count as isize)
+		} else {
+			Err(Error::EPERM)
+		}
+	}
+
+	fn seek(&self, file: &File, offset: i64, whence: i32) -> Result<i64> {
+		let new_pos = match whence {
+			SEEK_SET => offset,
+			SEEK_CUR => file.get_pos() + offset,
+			SEEK_END => 0, // Proc files are typically small
+			_ => return Err(Error::EINVAL),
+		};
+
+		if new_pos < 0 {
+			return Err(Error::EINVAL);
+		}
+
+		file.set_pos(new_pos);
+		Ok(new_pos)
+	}
+
+	fn ioctl(&self, file: &File, cmd: u32, arg: usize) -> Result<isize> {
+		Err(Error::ENOTTY)
+	}
+
+	fn mmap(&self, file: &File, vma: &mut crate::memory::VmaArea) -> Result<()> {
+		Err(Error::ENODEV)
+	}
+
+	fn fsync(&self, file: &File, datasync: bool) -> Result<()> {
+		Ok(())
+	}
+
+	fn poll(&self, file: &File, wait: &mut PollWait) -> Result<u32> {
+		Ok(POLLIN | POLLOUT)
+	}
+}
+
+/// Proc filesystem inode operations
+#[derive(Debug)]
+pub struct ProcInodeOps {
+	fs: *const ProcFs,
+}
+
+impl ProcInodeOps {
+	pub fn new(fs: &ProcFs) -> Self {
+		Self {
+			fs: fs as *const ProcFs,
+		}
+	}
+
+	fn get_fs(&self) -> &ProcFs {
+		unsafe { &*self.fs }
+	}
+}
+
+unsafe impl Send for ProcInodeOps {}
+unsafe impl Sync for ProcInodeOps {}
+
+impl InodeOperations for ProcInodeOps {
+	fn lookup(&self, dir: &Inode, name: &str) -> Result<Arc<Inode>> {
+		let fs = self.get_fs();
+		// Find the proc entry for this inode
+		// This is a simplified implementation
+		if let Some(child) = fs.root.find_child(name) {
+			let ino = fs.get_or_create_ino(&child);
+			let mode = match child.entry_type {
+				ProcEntryType::File => mode::S_IFREG | child.mode,
+				ProcEntryType::Directory => mode::S_IFDIR | child.mode,
+				ProcEntryType::Symlink => mode::S_IFLNK | child.mode,
+			};
+
+			let mut inode = Inode::new(ino, mode);
+			inode.set_operations(Arc::new(ProcInodeOps::new(fs)));
+			inode.set_file_operations(Arc::new(ProcFileOps::new(child)));
+
+			Ok(Arc::new(inode))
+		} else {
+			Err(Error::ENOENT)
+		}
+	}
+
+	fn create(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		Err(Error::EPERM) // Proc filesystem is read-only
+	}
+
+	fn mkdir(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		Err(Error::EPERM)
+	}
+
+	fn unlink(&self, dir: &Inode, name: &str) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn rmdir(&self, dir: &Inode, name: &str) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn symlink(&self, dir: &Inode, name: &str, target: &str) -> Result<Arc<Inode>> {
+		Err(Error::EPERM)
+	}
+
+	fn rename(
+		&self,
+		old_dir: &Inode,
+		old_name: &str,
+		new_dir: &Inode,
+		new_name: &str,
+	) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn setattr(&self, inode: &Inode, attr: &InodeAttr) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn getattr(&self, inode: &Inode) -> Result<InodeAttr> {
+		let generic_ops = GenericInodeOps;
+		generic_ops.getattr(inode)
+	}
+
+	fn readlink(&self, inode: &Inode) -> Result<String> {
+		Err(Error::EINVAL)
+	}
+
+	fn follow_link(&self, inode: &Inode) -> Result<Arc<Inode>> {
+		Err(Error::EINVAL)
+	}
+
+	fn truncate(&self, inode: &Inode, size: u64) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn getxattr(&self, inode: &Inode, name: &str) -> Result<Vec<u8>> {
+		Err(Error::ENODATA)
+	}
+
+	fn setxattr(&self, inode: &Inode, name: &str, value: &[u8], flags: u32) -> Result<()> {
+		Err(Error::EPERM)
+	}
+
+	fn listxattr(&self, inode: &Inode) -> Result<Vec<String>> {
+		Ok(Vec::new())
+	}
+
+	fn removexattr(&self, inode: &Inode, name: &str) -> Result<()> {
+		Err(Error::EPERM)
+	}
+}
+
+// Proc file read functions
+
+fn proc_version_read(_entry: &ProcEntry, content: &mut String) -> Result<()> {
+	content.push_str(&format!(
+		"{} version {} ({})\n",
+		crate::NAME,
+		crate::VERSION,
+		"rustc"
+	));
+	Ok(())
+}
+
+fn proc_meminfo_read(_entry: &ProcEntry, content: &mut String) -> Result<()> {
+	// TODO: Get actual memory statistics
+	let total_mem = 128 * 1024; // 128 MB placeholder
+	let free_mem = 64 * 1024; // 64 MB placeholder
+
+	content.push_str(&format!(
+		"MemTotal:     {} kB\n\
+         MemFree:      {} kB\n\
+         MemAvailable: {} kB\n\
+         Buffers:      {} kB\n\
+         Cached:       {} kB\n",
+		total_mem, free_mem, free_mem, 0, 0
+	));
+	Ok(())
+}
+
+fn proc_cpuinfo_read(_entry: &ProcEntry, content: &mut String) -> Result<()> {
+	// TODO: Get actual CPU information
+	content.push_str(
+		"processor\t: 0\n\
+         vendor_id\t: RustKernel\n\
+         cpu family\t: 1\n\
+         model\t\t: 1\n\
+         model name\t: Rust Kernel CPU\n\
+         stepping\t: 1\n\
+         microcode\t: 0x1\n\
+         cpu MHz\t\t: 1000.000\n\
+         cache size\t: 1024 KB\n\
+         flags\t\t: rust\n\n",
+	);
+	Ok(())
+}
+
+fn proc_uptime_read(_entry: &ProcEntry, content: &mut String) -> Result<()> {
+	// TODO: Get actual uptime
+	let uptime = 100.0; // 100 seconds placeholder
+	let idle = 90.0; // 90 seconds idle placeholder
+
+	content.push_str(&format!("{:.2} {:.2}\n", uptime, idle));
+	Ok(())
+}
+
+fn proc_loadavg_read(_entry: &ProcEntry, content: &mut String) -> Result<()> {
+	// TODO: Get actual load average
+	content.push_str("0.00 0.00 0.00 1/1 1\n");
+	Ok(())
+}
+
+fn proc_stat_read(_entry: &ProcEntry, content: &mut String) -> Result<()> {
+	// TODO: Get actual system statistics
+	content.push_str(
+		"cpu  0 0 0 1000 0 0 0 0 0 0\n\
+         cpu0 0 0 0 1000 0 0 0 0 0 0\n\
+         intr 0\n\
+         ctxt 0\n\
+         btime 0\n\
+         processes 1\n\
+         procs_running 1\n\
+         procs_blocked 0\n",
+	);
+	Ok(())
+}
+
+fn proc_mounts_read(_entry: &ProcEntry, content: &mut String) -> Result<()> {
+	// TODO: Get actual mount information
+	let mounts = crate::fs::mount::get_all_mounts();
+	for mount in mounts {
+		content.push_str(&format!("none {} ramfs rw 0 0\n", mount));
+	}
+	Ok(())
+}
+
+/// Mount proc filesystem
+pub fn mount_procfs(_dev_name: &str, _flags: u32, _data: Option<&str>) -> Result<Arc<SuperBlock>> {
+	let mut sb = SuperBlock::new("proc")?;
+	sb.s_magic = 0x9fa0; // PROC_SUPER_MAGIC
+
+	let procfs = Box::leak(Box::new(ProcFs::new()));
+	sb.s_fs_info = Some(procfs as *mut ProcFs as *mut u8);
+
+	// Create root inode
+	let root_inode = Arc::new({
+		let mut inode = Inode::new(1, mode::S_IFDIR | 0o755);
+		inode.set_operations(Arc::new(ProcInodeOps::new(procfs)));
+		inode
+	});
+
+	let root_dentry = Arc::new(Dentry::new(String::from("/"), Some(root_inode)));
+	sb.s_root = Some(root_dentry);
+
+	Ok(Arc::new(sb))
+}
+
+/// Register proc filesystem
+pub fn register_procfs() -> Result<()> {
+	let procfs_type = FileSystemType::new(
+		String::from("proc"),
+		|_fstype, flags, _dev_name, data| mount_procfs(_dev_name, flags, data),
+		|_sb| Ok(()),
+	);
+
+	// TODO: Register with VFS
+	crate::console::print_info("Registered proc filesystem\n");
+	Ok(())
+}

kernel/src/fs/ramfs.rs

@@ -0,0 +1,406 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Simple RAM filesystem implementation
+
+use alloc::{boxed::Box, collections::BTreeMap, string::String, vec::Vec}; // Add Box import
+use core::sync::atomic::{AtomicU64, Ordering};
+
+use crate::error::{Error, Result};
+use crate::fs::inode::GenericInodeOps;
+use crate::fs::*;
+use crate::sync::{Arc, Mutex};
+
+const NAME_MAX: usize = 255;
+
+/// RAM filesystem superblock
+pub struct RamFs {
+	/// Next inode number
+	next_ino: AtomicU64,
+	/// Inode storage
+	inodes: Mutex<BTreeMap<u64, Arc<Inode>>>,
+	/// Directory entries
+	entries: Mutex<BTreeMap<u64, Vec<Arc<Dentry>>>>,
+}
+
+impl RamFs {
+	pub fn new() -> Self {
+		Self {
+			next_ino: AtomicU64::new(1),
+			inodes: Mutex::new(BTreeMap::new()),
+			entries: Mutex::new(BTreeMap::new()),
+		}
+	}
+
+	fn alloc_ino(&self) -> u64 {
+		self.next_ino.fetch_add(1, Ordering::Relaxed)
+	}
+
+	fn create_inode(&self, mode: u32) -> Arc<Inode> {
+		let ino = self.alloc_ino();
+		let mut inode = Inode::new(ino, mode);
+		inode.set_operations(Arc::new(RamFsInodeOps::new(self)));
+
+		let inode = Arc::new(inode);
+
+		let mut inodes = self.inodes.lock();
+		inodes.insert(ino, inode.clone());
+
+		if mode::s_isdir(mode) {
+			let mut entries = self.entries.lock();
+			entries.insert(ino, Vec::new());
+		}
+
+		inode
+	}
+
+	fn get_inode(&self, ino: u64) -> Option<Arc<Inode>> {
+		let inodes = self.inodes.lock();
+		inodes.get(&ino).cloned()
+	}
+
+	fn add_entry(&self, dir_ino: u64, name: String, child_ino: u64) -> Result<()> {
+		let child_inode = self.get_inode(child_ino).ok_or(Error::ENOENT)?;
+		let dentry = Arc::new(Dentry::new(name, Some(child_inode)));
+
+		let mut entries = self.entries.lock();
+		if let Some(dir_entries) = entries.get_mut(&dir_ino) {
+			dir_entries.push(dentry);
+			Ok(())
+		} else {
+			Err(Error::ENOTDIR)
+		}
+	}
+
+	fn find_entry(&self, dir_ino: u64, name: &str) -> Option<Arc<Dentry>> {
+		let entries = self.entries.lock();
+		if let Some(dir_entries) = entries.get(&dir_ino) {
+			for entry in dir_entries {
+				if entry.d_name == name {
+					return Some(entry.clone());
+				}
+			}
+		}
+		None
+	}
+
+	fn remove_entry(&self, dir_ino: u64, name: &str) -> Result<()> {
+		let mut entries = self.entries.lock();
+		if let Some(dir_entries) = entries.get_mut(&dir_ino) {
+			if let Some(pos) = dir_entries.iter().position(|e| e.d_name == name) {
+				dir_entries.remove(pos);
+				Ok(())
+			} else {
+				Err(Error::ENOENT)
+			}
+		} else {
+			Err(Error::ENOTDIR)
+		}
+	}
+}
+
+/// RAM filesystem inode operations
+#[derive(Debug)]
+pub struct RamFsInodeOps {
+	fs: *const RamFs,
+}
+
+impl RamFsInodeOps {
+	fn new(fs: &RamFs) -> Self {
+		Self {
+			fs: fs as *const RamFs,
+		}
+	}
+
+	fn get_fs(&self) -> &RamFs {
+		unsafe { &*self.fs }
+	}
+}
+
+unsafe impl Send for RamFsInodeOps {}
+unsafe impl Sync for RamFsInodeOps {}
+
+impl InodeOperations for RamFsInodeOps {
+	fn lookup(&self, dir: &Inode, name: &str) -> Result<Arc<Inode>> {
+		let fs = self.get_fs();
+		if let Some(entry) = fs.find_entry(dir.i_ino, name) {
+			if let Some(inode) = &entry.d_inode {
+				Ok(Arc::clone(inode))
+			} else {
+				Err(Error::ENOENT)
+			}
+		} else {
+			Err(Error::ENOENT)
+		}
+	}
+
+	fn create(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		let fs = self.get_fs();
+
+		// Check if entry already exists
+		if fs.find_entry(dir.i_ino, name).is_some() {
+			return Err(Error::EEXIST);
+		}
+
+		let inode = fs.create_inode(mode | mode::S_IFREG);
+		fs.add_entry(dir.i_ino, String::from(name), inode.i_ino)?;
+
+		Ok(inode)
+	}
+
+	fn mkdir(&self, dir: &Inode, name: &str, mode: u32) -> Result<Arc<Inode>> {
+		let fs = self.get_fs();
+
+		// Check if entry already exists
+		if fs.find_entry(dir.i_ino, name).is_some() {
+			return Err(Error::EEXIST);
+		}
+
+		let inode = fs.create_inode(mode | mode::S_IFDIR);
+		fs.add_entry(dir.i_ino, String::from(name), inode.i_ino)?;
+
+		// Add . and .. entries
+		fs.add_entry(inode.i_ino, String::from("."), inode.i_ino)?;
+		fs.add_entry(inode.i_ino, String::from(".."), dir.i_ino)?;
+
+		Ok(inode)
+	}
+
+	fn unlink(&self, dir: &Inode, name: &str) -> Result<()> {
+		let fs = self.get_fs();
+		fs.remove_entry(dir.i_ino, name)
+	}
+
+	fn rmdir(&self, dir: &Inode, name: &str) -> Result<()> {
+		let fs = self.get_fs();
+
+		// Check if directory is empty (only . and .. entries)
+		let entries = fs.entries.lock();
+		if let Some(target_inode) = fs
+			.find_entry(dir.i_ino, name)
+			.and_then(|e| e.d_inode.clone())
+		{
+			if let Some(dir_entries) = entries.get(&target_inode.i_ino) {
+				if dir_entries.len() > 2 {
+					return Err(Error::ENOTEMPTY);
+				}
+			}
+		}
+		drop(entries);
+
+		fs.remove_entry(dir.i_ino, name)
+	}
+
+	fn symlink(&self, dir: &Inode, name: &str, target: &str) -> Result<Arc<Inode>> {
+		let fs = self.get_fs();
+
+		// Check if entry already exists
+		if fs.find_entry(dir.i_ino, name).is_some() {
+			return Err(Error::EEXIST);
+		}
+
+		let inode = fs.create_inode(mode::S_IFLNK | 0o777);
+		// TODO: Store symlink target
+		fs.add_entry(dir.i_ino, String::from(name), inode.i_ino)?;
+
+		Ok(inode)
+	}
+
+	fn rename(
+		&self,
+		old_dir: &Inode,
+		old_name: &str,
+		new_dir: &Inode,
+		new_name: &str,
+	) -> Result<()> {
+		let fs = self.get_fs();
+
+		// Find the entry to rename
+		if let Some(entry) = fs.find_entry(old_dir.i_ino, old_name) {
+			// Remove from old location
+			fs.remove_entry(old_dir.i_ino, old_name)?;
+
+			// Add to new location
+			if let Some(inode) = &entry.d_inode {
+				fs.add_entry(new_dir.i_ino, String::from(new_name), inode.i_ino)?;
+			}
+
+			Ok(())
+		} else {
+			Err(Error::ENOENT)
+		}
+	}
+
+	fn setattr(&self, inode: &Inode, attr: &InodeAttr) -> Result<()> {
+		// Apply basic attributes using generic implementation
+		let generic_ops = GenericInodeOps;
+		generic_ops.setattr(inode, attr)
+	}
+
+	fn getattr(&self, inode: &Inode) -> Result<InodeAttr> {
+		let generic_ops = GenericInodeOps;
+		generic_ops.getattr(inode)
+	}
+
+	fn readlink(&self, inode: &Inode) -> Result<String> {
+		// TODO: Return stored symlink target
+		Err(Error::EINVAL)
+	}
+
+	fn follow_link(&self, inode: &Inode) -> Result<Arc<Inode>> {
+		// TODO: Follow symlink to target
+		Err(Error::EINVAL)
+	}
+
+	fn truncate(&self, inode: &Inode, size: u64) -> Result<()> {
+		inode.set_size(size);
+		Ok(())
+	}
+
+	fn getxattr(&self, inode: &Inode, name: &str) -> Result<Vec<u8>> {
+		Err(Error::ENODATA)
+	}
+
+	fn setxattr(&self, inode: &Inode, name: &str, value: &[u8], flags: u32) -> Result<()> {
+		Err(Error::ENOSYS)
+	}
+
+	fn listxattr(&self, inode: &Inode) -> Result<Vec<String>> {
+		Ok(Vec::new())
+	}
+
+	fn removexattr(&self, inode: &Inode, name: &str) -> Result<()> {
+		Err(Error::ENODATA)
+	}
+}
+
+/// Mount RAM filesystem
+pub fn mount_ramfs(_dev_name: &str, _flags: u32, _data: Option<&str>) -> Result<Arc<SuperBlock>> {
+	let mut sb = SuperBlock::new("ramfs")?;
+	sb.s_magic = 0x858458f6; // RAMFS magic
+	sb.set_operations(Arc::new(RamFsSuperOps));
+
+	let ramfs = Box::leak(Box::new(RamFs::new()));
+	sb.s_fs_info = Some(ramfs as *mut RamFs as *mut u8);
+
+	// Create root directory
+	let root_inode = ramfs.create_inode(mode::S_IFDIR | 0o755);
+	let root_dentry = Arc::new(Dentry::new(String::from("/"), Some(root_inode)));
+
+	let sb = Arc::new(sb);
+	Ok(sb)
+}
+
+/// RAM filesystem superblock operations
+#[derive(Debug)]
+pub struct RamFsSuperOps;
+
+impl SuperOperations for RamFsSuperOps {
+	fn alloc_inode(&self, sb: &SuperBlock) -> Result<Arc<Inode>> {
+		let ramfs = unsafe { &*(sb.s_fs_info.unwrap() as *const RamFs) };
+		Ok(ramfs.create_inode(0o644))
+	}
+
+	fn destroy_inode(&self, inode: &Inode) -> Result<()> {
+		Ok(())
+	}
+
+	fn write_inode(&self, inode: &Inode, sync: bool) -> Result<()> {
+		// RAM filesystem doesn't need to write inodes
+		Ok(())
+	}
+
+	fn delete_inode(&self, inode: &Inode) -> Result<()> {
+		Ok(())
+	}
+
+	fn put_super(&self, sb: &SuperBlock) -> Result<()> {
+		if let Some(fs_info) = sb.s_fs_info {
+			unsafe {
+				let ramfs = Box::from_raw(fs_info as *mut RamFs);
+				drop(ramfs);
+			}
+		}
+		Ok(())
+	}
+
+	fn write_super(&self, sb: &SuperBlock) -> Result<()> {
+		// Nothing to write for RAM filesystem
+		Ok(())
+	}
+
+	fn sync_fs(&self, sb: &SuperBlock, wait: bool) -> Result<()> {
+		// Nothing to sync for RAM filesystem
+		Ok(())
+	}
+
+	fn freeze_fs(&self, sb: &SuperBlock) -> Result<()> {
+		Ok(())
+	}
+
+	fn unfreeze_fs(&self, sb: &SuperBlock) -> Result<()> {
+		Ok(())
+	}
+
+	fn statfs(&self, sb: &SuperBlock) -> Result<KStatFs> {
+		Ok(KStatFs {
+			f_type: sb.s_magic as u64,
+			f_bsize: sb.s_blocksize as u64,
+			f_blocks: 0, // Unlimited
+			f_bfree: 0,  // Unlimited
+			f_bavail: 0, // Unlimited
+			f_files: 0,  // Dynamic
+			f_ffree: 0,  // Unlimited
+			f_fsid: [0, 0],
+			f_namelen: NAME_MAX as u64,
+			f_frsize: sb.s_blocksize as u64,
+			f_flags: 0,
+			f_spare: [0; 4],
+		})
+	}
+
+	fn remount_fs(&self, sb: &SuperBlock, flags: u32, data: Option<&str>) -> Result<()> {
+		sb.s_flags.store(flags, Ordering::Relaxed);
+		Ok(())
+	}
+
+	fn show_options(&self, sb: &SuperBlock) -> Result<String> {
+		Ok(String::new())
+	}
+}
+
+/// Kill RAM filesystem superblock
+pub fn kill_ramfs(sb: &SuperBlock) -> Result<()> {
+	if let Some(ref ops) = sb.s_op {
+		ops.put_super(sb)
+	} else {
+		Ok(())
+	}
+}
+
+/// Create a RAM filesystem superblock
+pub fn create_ramfs_superblock() -> Result<Arc<SuperBlock>> {
+	let mut sb = SuperBlock::new("ramfs")?;
+	sb.s_magic = 0x858458f6; // RAMFS magic
+	sb.set_operations(Arc::new(RamFsSuperOps));
+
+	let ramfs = Box::leak(Box::new(RamFs::new()));
+	sb.s_fs_info = Some(ramfs as *mut RamFs as *mut u8);
+
+	// Create root directory
+	let root_inode = ramfs.create_inode(mode::S_IFDIR | 0o755);
+
+	Ok(Arc::new(sb))
+}
+
+/// Register RAM filesystem
+pub fn register_ramfs() -> Result<()> {
+	let ramfs_type = FileSystemType::new(
+		String::from("ramfs"),
+		|_fstype, flags, _dev_name, data| mount_ramfs(_dev_name, flags, data),
+		|sb| kill_ramfs(sb),
+	);
+
+	// TODO: Register with VFS
+	crate::console::print_info("Registered ramfs filesystem\n");
+	Ok(())
+}

kernel/src/fs/super_block.rs

@@ -0,0 +1,363 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Superblock abstraction - Linux compatible
+
+use alloc::string::String;
+use alloc::vec::Vec;
+use core::sync::atomic::{AtomicU32, AtomicU64, Ordering};
+
+use crate::device::DeviceNumber;
+use crate::error::Result;
+use crate::sync::{Arc, Mutex};
+
+/// Superblock structure - similar to Linux struct super_block
+#[derive(Debug)]
+pub struct SuperBlock {
+	/// Device number
+	pub s_dev: DeviceNumber,
+	/// Block size
+	pub s_blocksize: u32,
+	/// Block size bits
+	pub s_blocksize_bits: u8,
+	/// Maximum file size
+	pub s_maxbytes: u64,
+	/// File system type
+	pub s_type: Option<Arc<FileSystemType>>,
+	/// Superblock operations
+	pub s_op: Option<Arc<dyn SuperOperations>>,
+	/// Root dentry
+	pub s_root: Option<Arc<super::Dentry>>,
+	/// Mount point
+	pub s_mount: Option<Arc<super::VfsMount>>,
+	/// File system flags
+	pub s_flags: AtomicU32,
+	/// File system magic number
+	pub s_magic: u32,
+	/// List of inodes
+	pub s_inodes: Mutex<Vec<Arc<super::Inode>>>,
+	/// Next inode number
+	pub s_next_ino: AtomicU64,
+	/// Private data
+	pub s_fs_info: Option<*mut u8>,
+	/// Dirty inodes
+	pub s_dirty: Mutex<Vec<Arc<super::Inode>>>,
+	/// Reference count
+	pub s_count: AtomicU32,
+	/// File system name
+	pub s_id: String,
+}
+
+impl SuperBlock {
+	/// Create a new superblock
+	pub fn new(fstype: &str) -> Result<Self> {
+		Ok(Self {
+			s_dev: DeviceNumber::new(0, 0),
+			s_blocksize: 4096,
+			s_blocksize_bits: 12,
+			s_maxbytes: 0x7fffffffffffffff,
+			s_type: None,
+			s_op: None,
+			s_root: None,
+			s_mount: None,
+			s_flags: AtomicU32::new(0),
+			s_magic: 0,
+			s_inodes: Mutex::new(Vec::new()),
+			s_next_ino: AtomicU64::new(1),
+			s_fs_info: None,
+			s_dirty: Mutex::new(Vec::new()),
+			s_count: AtomicU32::new(1),
+			s_id: String::from(fstype),
+		})
+	}
+
+	/// Set superblock operations
+	pub fn set_operations(&mut self, ops: Arc<dyn SuperOperations>) {
+		self.s_op = Some(ops);
+	}
+
+	/// Allocate a new inode
+	pub fn alloc_inode(&self, mode: u32) -> Result<Arc<super::Inode>> {
+		let ino = self.s_next_ino.fetch_add(1, Ordering::Relaxed);
+		let mut inode = super::Inode::new(ino, mode);
+		inode.i_sb = Some(Arc::new(unsafe {
+			// SAFETY: We're creating a weak reference to avoid cycles
+			core::ptr::read(self as *const Self)
+		}));
+
+		let inode = Arc::new(inode);
+
+		// Add to inode list
+		let mut inodes = self.s_inodes.lock();
+		inodes.push(inode.clone());
+
+		Ok(inode)
+	}
+
+	/// Write superblock to disk
+	pub fn write_super(&self) -> Result<()> {
+		if let Some(ref ops) = self.s_op {
+			ops.write_super(self)
+		} else {
+			Ok(())
+		}
+	}
+
+	/// Put superblock (decrement reference count)
+	pub fn put_super(&self) -> Result<()> {
+		let old_count = self.s_count.fetch_sub(1, Ordering::Relaxed);
+		if old_count == 1 {
+			// Last reference, cleanup
+			if let Some(ref ops) = self.s_op {
+				ops.put_super(self)?;
+			}
+		}
+		Ok(())
+	}
+
+	/// Get superblock statistics
+	pub fn statfs(&self) -> Result<super::KStatFs> {
+		if let Some(ref ops) = self.s_op {
+			ops.statfs(self)
+		} else {
+			// Default statistics
+			Ok(super::KStatFs {
+				f_type: self.s_magic as u64,
+				f_bsize: self.s_blocksize as u64,
+				f_blocks: 0,
+				f_bfree: 0,
+				f_bavail: 0,
+				f_files: 0,
+				f_ffree: 0,
+				f_fsid: [0, 0],
+				f_namelen: super::NAME_MAX as u64,
+				f_frsize: self.s_blocksize as u64,
+				f_flags: self.s_flags.load(Ordering::Relaxed) as u64,
+				f_spare: [0; 4],
+			})
+		}
+	}
+
+	/// Sync filesystem
+	pub fn sync_fs(&self, wait: bool) -> Result<()> {
+		if let Some(ref ops) = self.s_op {
+			ops.sync_fs(self, wait)
+		} else {
+			Ok(())
+		}
+	}
+
+	/// Freeze filesystem
+	pub fn freeze_fs(&self) -> Result<()> {
+		if let Some(ref ops) = self.s_op {
+			ops.freeze_fs(self)
+		} else {
+			Ok(())
+		}
+	}
+
+	/// Unfreeze filesystem
+	pub fn unfreeze_fs(&self) -> Result<()> {
+		if let Some(ref ops) = self.s_op {
+			ops.unfreeze_fs(self)
+		} else {
+			Ok(())
+		}
+	}
+
+	/// Mark inode as dirty
+	pub fn mark_dirty(&self, inode: Arc<super::Inode>) {
+		let mut dirty = self.s_dirty.lock();
+		dirty.push(inode);
+	}
+
+	/// Write back dirty inodes
+	pub fn write_dirty(&self) -> Result<()> {
+		let mut dirty = self.s_dirty.lock();
+		for inode in dirty.drain(..) {
+			// TODO: Write inode to disk
+		}
+		Ok(())
+	}
+}
+
+unsafe impl Send for SuperBlock {}
+unsafe impl Sync for SuperBlock {}
+
+/// Superblock operations trait - similar to Linux super_operations
+pub trait SuperOperations: Send + Sync + core::fmt::Debug {
+	/// Allocate inode
+	fn alloc_inode(&self, sb: &SuperBlock) -> Result<Arc<super::Inode>>;
+
+	/// Destroy inode
+	fn destroy_inode(&self, inode: &super::Inode) -> Result<()>;
+
+	/// Write inode
+	fn write_inode(&self, inode: &super::Inode, sync: bool) -> Result<()>;
+
+	/// Delete inode
+	fn delete_inode(&self, inode: &super::Inode) -> Result<()>;
+
+	/// Put superblock
+	fn put_super(&self, sb: &SuperBlock) -> Result<()>;
+
+	/// Write superblock
+	fn write_super(&self, sb: &SuperBlock) -> Result<()>;
+
+	/// Sync filesystem
+	fn sync_fs(&self, sb: &SuperBlock, wait: bool) -> Result<()>;
+
+	/// Freeze filesystem
+	fn freeze_fs(&self, sb: &SuperBlock) -> Result<()>;
+
+	/// Unfreeze filesystem
+	fn unfreeze_fs(&self, sb: &SuperBlock) -> Result<()>;
+
+	/// Get filesystem statistics
+	fn statfs(&self, sb: &SuperBlock) -> Result<super::KStatFs>;
+
+	/// Remount filesystem
+	fn remount_fs(&self, sb: &SuperBlock, flags: u32, data: Option<&str>) -> Result<()>;
+
+	/// Show mount options
+	fn show_options(&self, sb: &SuperBlock) -> Result<String>;
+}
+
+/// File system type structure - similar to Linux file_system_type
+#[derive(Debug)]
+pub struct FileSystemType {
+	/// File system name
+	pub name: String,
+	/// File system flags
+	pub fs_flags: u32,
+	/// Mount function
+	pub mount: fn(
+		fstype: &FileSystemType,
+		flags: u32,
+		dev_name: &str,
+		data: Option<&str>,
+	) -> Result<Arc<SuperBlock>>,
+	/// Kill superblock function
+	pub kill_sb: fn(sb: &SuperBlock) -> Result<()>,
+	/// Owner module
+	pub owner: Option<&'static str>,
+}
+
+impl FileSystemType {
+	/// Create a new file system type
+	pub fn new(
+		name: String,
+		mount: fn(&FileSystemType, u32, &str, Option<&str>) -> Result<Arc<SuperBlock>>,
+		kill_sb: fn(&SuperBlock) -> Result<()>,
+	) -> Self {
+		Self {
+			name,
+			fs_flags: 0,
+			mount,
+			kill_sb,
+			owner: None,
+		}
+	}
+
+	/// Mount this filesystem type
+	pub fn do_mount(
+		&self,
+		flags: u32,
+		dev_name: &str,
+		data: Option<&str>,
+	) -> Result<Arc<SuperBlock>> {
+		(self.mount)(self, flags, dev_name, data)
+	}
+
+	/// Kill superblock
+	pub fn do_kill_sb(&self, sb: &SuperBlock) -> Result<()> {
+		(self.kill_sb)(sb)
+	}
+}
+
+/// Generic superblock operations
+#[derive(Debug)]
+pub struct GenericSuperOps;
+
+impl SuperOperations for GenericSuperOps {
+	fn alloc_inode(&self, sb: &SuperBlock) -> Result<Arc<super::Inode>> {
+		sb.alloc_inode(0o644)
+	}
+
+	fn destroy_inode(&self, inode: &super::Inode) -> Result<()> {
+		Ok(())
+	}
+
+	fn write_inode(&self, inode: &super::Inode, sync: bool) -> Result<()> {
+		Ok(())
+	}
+
+	fn delete_inode(&self, inode: &super::Inode) -> Result<()> {
+		Ok(())
+	}
+
+	fn put_super(&self, sb: &SuperBlock) -> Result<()> {
+		Ok(())
+	}
+
+	fn write_super(&self, sb: &SuperBlock) -> Result<()> {
+		Ok(())
+	}
+
+	fn sync_fs(&self, sb: &SuperBlock, wait: bool) -> Result<()> {
+		sb.write_dirty()
+	}
+
+	fn freeze_fs(&self, sb: &SuperBlock) -> Result<()> {
+		Ok(())
+	}
+
+	fn unfreeze_fs(&self, sb: &SuperBlock) -> Result<()> {
+		Ok(())
+	}
+
+	fn statfs(&self, sb: &SuperBlock) -> Result<super::KStatFs> {
+		sb.statfs()
+	}
+
+	fn remount_fs(&self, sb: &SuperBlock, flags: u32, data: Option<&str>) -> Result<()> {
+		sb.s_flags.store(flags, Ordering::Relaxed);
+		Ok(())
+	}
+
+	fn show_options(&self, sb: &SuperBlock) -> Result<String> {
+		Ok(String::new())
+	}
+}
+
+/// File system flags
+pub const FS_REQUIRES_DEV: u32 = 1;
+pub const FS_BINARY_MOUNTDATA: u32 = 2;
+pub const FS_HAS_SUBTYPE: u32 = 4;
+pub const FS_USERNS_MOUNT: u32 = 8;
+pub const FS_DISALLOW_NOTIFY_PERM: u32 = 16;
+pub const FS_RENAME_DOES_D_MOVE: u32 = 32;
+
+/// Mount flags
+pub const MS_RDONLY: u32 = 1;
+pub const MS_NOSUID: u32 = 2;
+pub const MS_NODEV: u32 = 4;
+pub const MS_NOEXEC: u32 = 8;
+pub const MS_SYNCHRONOUS: u32 = 16;
+pub const MS_REMOUNT: u32 = 32;
+pub const MS_MANDLOCK: u32 = 64;
+pub const MS_DIRSYNC: u32 = 128;
+pub const MS_NOATIME: u32 = 1024;
+pub const MS_NODIRATIME: u32 = 2048;
+pub const MS_BIND: u32 = 4096;
+pub const MS_MOVE: u32 = 8192;
+pub const MS_REC: u32 = 16384;
+pub const MS_SILENT: u32 = 32768;
+pub const MS_POSIXACL: u32 = 1 << 16;
+pub const MS_UNBINDABLE: u32 = 1 << 17;
+pub const MS_PRIVATE: u32 = 1 << 18;
+pub const MS_SLAVE: u32 = 1 << 19;
+pub const MS_SHARED: u32 = 1 << 20;
+pub const MS_RELATIME: u32 = 1 << 21;
+pub const MS_KERNMOUNT: u32 = 1 << 22;
+pub const MS_I_VERSION: u32 = 1 << 23;
+pub const MS_STRICTATIME: u32 = 1 << 24;

kernel/src/hardware.rs

@@ -0,0 +1,278 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Hardware detection and initialization
+
+use alloc::format;
+use alloc::string::{String, ToString};
+use alloc::vec::Vec;
+
+use crate::driver::{PciBar, PciDevice};
+use crate::error::Result;
+/// CPU Information
+#[derive(Debug, Clone)]
+pub struct CpuInfo {
+	pub vendor: String,
+	pub model_name: String,
+	pub family: u32,
+	pub model: u32,
+	pub stepping: u32,
+	pub features: Vec<String>,
+	pub cache_size: u32,
+	pub core_count: u32,
+	pub thread_count: u32,
+}
+
+/// System Information
+#[derive(Debug, Clone)]
+pub struct SystemInfo {
+	pub cpu: CpuInfo,
+	pub total_memory: usize,
+	pub available_memory: usize,
+	pub boot_device: String,
+	pub acpi_available: bool,
+	pub pci_devices: Vec<PciDevice>,
+}
+
+/// Initialize hardware detection
+pub fn init() -> Result<()> {
+	crate::info!("Initializing hardware detection...");
+
+	// Detect CPU
+	let cpu_info = detect_cpu()?;
+	crate::info!("CPU: {} {}", cpu_info.vendor, cpu_info.model_name);
+	crate::info!("CPU Cores: {}", cpu_info.core_count);
+
+	// Detect memory
+	let memory_info = detect_memory()?;
+	crate::info!("Total Memory: {} MB", memory_info / (1024 * 1024));
+
+	// Detect PCI devices
+	let pci_devices = detect_pci_devices()?;
+	crate::info!("Found {} PCI devices", pci_devices.len());
+
+	Ok(())
+}
+
+/// Detect CPU information
+pub fn detect_cpu() -> Result<CpuInfo> {
+	let mut cpu_info = CpuInfo {
+		vendor: String::new(),
+		model_name: String::new(),
+		family: 0,
+		model: 0,
+		stepping: 0,
+		features: Vec::new(),
+		cache_size: 0,
+		core_count: 1,
+		thread_count: 1,
+	};
+
+	// Get CPU vendor
+	let (_, vendor_ebx, vendor_ecx, vendor_edx) = cpuid(0);
+	cpu_info.vendor = format!(
+		"{}{}{}",
+		u32_to_string(vendor_ebx),
+		u32_to_string(vendor_edx),
+		u32_to_string(vendor_ecx)
+	);
+
+	// Get CPU features and family/model
+	let (version_eax, _ebx, feature_ecx, feature_edx) = cpuid(1);
+	cpu_info.family = (version_eax >> 8) & 0xF;
+	cpu_info.model = (version_eax >> 4) & 0xF;
+	cpu_info.stepping = version_eax & 0xF;
+
+	// Extended family/model for newer CPUs
+	if cpu_info.family == 0xF {
+		cpu_info.family += (version_eax >> 20) & 0xFF;
+	}
+	if cpu_info.family == 0x6 || cpu_info.family == 0xF {
+		cpu_info.model += ((version_eax >> 16) & 0xF) << 4;
+	}
+
+	// Check for common features
+	if feature_edx & (1 << 23) != 0 {
+		cpu_info.features.push("MMX".to_string());
+	}
+	if feature_edx & (1 << 25) != 0 {
+		cpu_info.features.push("SSE".to_string());
+	}
+	if feature_edx & (1 << 26) != 0 {
+		cpu_info.features.push("SSE2".to_string());
+	}
+	if feature_ecx & (1 << 0) != 0 {
+		cpu_info.features.push("SSE3".to_string());
+	}
+	if feature_ecx & (1 << 9) != 0 {
+		cpu_info.features.push("SSSE3".to_string());
+	}
+	if feature_ecx & (1 << 19) != 0 {
+		cpu_info.features.push("SSE4.1".to_string());
+	}
+	if feature_ecx & (1 << 20) != 0 {
+		cpu_info.features.push("SSE4.2".to_string());
+	}
+
+	// Get model name from extended CPUID
+	let max_extended = cpuid(0x80000000).0;
+	if max_extended >= 0x80000004 {
+		let mut model_name = String::new();
+		for i in 0x80000002..=0x80000004 {
+			let (eax, ebx, ecx, edx) = cpuid(i);
+			model_name.push_str(&u32_to_string(eax));
+			model_name.push_str(&u32_to_string(ebx));
+			model_name.push_str(&u32_to_string(ecx));
+			model_name.push_str(&u32_to_string(edx));
+		}
+		cpu_info.model_name = model_name.trim().to_string();
+	}
+
+	Ok(cpu_info)
+}
+
+/// Detect system memory
+pub fn detect_memory() -> Result<usize> {
+	// Use multiple methods to detect memory
+
+	// Method 1: CMOS
+	let cmos_memory = unsafe {
+		crate::arch::x86_64::port::outb(0x70, 0x17);
+		let low = crate::arch::x86_64::port::inb(0x71) as usize;
+		crate::arch::x86_64::port::outb(0x70, 0x18);
+		let high = crate::arch::x86_64::port::inb(0x71) as usize;
+
+		let extended_mem = (high << 8) | low; // in KB
+		1024 * 1024 + (extended_mem * 1024) // Base 1MB + extended
+	};
+
+	// Method 2: Try to probe memory (simplified)
+	let probe_memory = probe_memory_size();
+
+	// Use the larger of the two methods
+	let detected_memory = core::cmp::max(cmos_memory, probe_memory);
+
+	// Sanity check
+	if detected_memory < 16 * 1024 * 1024 {
+		Ok(64 * 1024 * 1024) // Default to 64MB
+	} else if detected_memory > 16 * 1024 * 1024 * 1024 {
+		Ok(8 * 1024 * 1024 * 1024) // Cap at 8GB
+	} else {
+		Ok(detected_memory)
+	}
+}
+
+/// Probe memory size by testing access
+fn probe_memory_size() -> usize {
+	// Simplified memory probing - just return a reasonable default
+	// In a real implementation, this would carefully probe memory ranges
+	512 * 1024 * 1024 // 512MB default
+}
+
+/// Detect PCI devices
+pub fn detect_pci_devices() -> Result<Vec<PciDevice>> {
+	let mut devices = Vec::new();
+
+	// Scan PCI bus 0 (simplified)
+	for device in 0..32 {
+		for function in 0..8 {
+			let vendor_id = pci_config_read(0, device, function, 0x00) as u16;
+			if vendor_id != 0xFFFF {
+				let device_id =
+					(pci_config_read(0, device, function, 0x00) >> 16) as u16;
+				let class_info = pci_config_read(0, device, function, 0x08);
+				let revision =
+					(pci_config_read(0, device, function, 0x08) & 0xFF) as u8;
+				let mut bars = [PciBar::new(); 6];
+				for i in 0..6 {
+					let bar_val = pci_config_read(
+						0,
+						device,
+						function,
+						0x10 + (i * 4),
+					);
+					if bar_val == 0 {
+						continue;
+					}
+					let is_io = bar_val & 1 != 0;
+					if is_io {
+						bars[i as usize].address =
+							(bar_val & 0xFFFFFFFC) as u64;
+					} else {
+						bars[i as usize].address =
+							(bar_val & 0xFFFFFFF0) as u64;
+					}
+					bars[i as usize].flags = bar_val & 0xF;
+				}
+
+				devices.push(PciDevice {
+					bus: 0,
+					slot: device,
+					function,
+					vendor: vendor_id,
+					device: device_id,
+					class: (class_info >> 16),
+					revision,
+					subsystem_vendor: 0, // Not implemented
+					subsystem_device: 0, // Not implemented
+					irq: 0,              // Not implemented
+					bars,
+				});
+			}
+		}
+	}
+
+	Ok(devices)
+}
+
+/// Read PCI configuration space
+pub(crate) fn pci_config_read(bus: u8, device: u8, function: u8, offset: u8) -> u32 {
+	let address = 0x80000000u32
+		| ((bus as u32) << 16)
+		| ((device as u32) << 11)
+		| ((function as u32) << 8)
+		| (offset as u32 & 0xFC);
+
+	unsafe {
+		crate::arch::x86_64::port::outl(0xCF8, address);
+		crate::arch::x86_64::port::inl(0xCFC)
+	}
+}
+
+/// Execute CPUID instruction (simplified to avoid RBX conflicts)
+fn cpuid(leaf: u32) -> (u32, u32, u32, u32) {
+	// For now, return simplified values to avoid RBX register conflicts
+	match leaf {
+		0 => (0x0000000D, 0x756e6547, 0x6c65746e, 0x49656e69), // "GenuineIntel"
+		1 => (0x000906E9, 0x00100800, 0x7FFAFBBF, 0xBFEBFBFF), // Typical Intel CPU
+		0x80000000 => (0x80000008, 0, 0, 0),
+		0x80000002 => (0x65746E49, 0x2952286C, 0x726F4320, 0x4D542865), /* "Intel(R) Core(TM" */
+		0x80000003 => (0x35692029, 0x3034332D, 0x20555043, 0x20402030), // ") i5-4340
+		// CPU @ "
+		0x80000004 => (0x30302E33, 0x007A4847, 0x00000000, 0x00000000), // "3.00GHz"
+		_ => (0, 0, 0, 0),
+	}
+}
+
+/// Convert u32 to 4-character string
+fn u32_to_string(value: u32) -> String {
+	let bytes = value.to_le_bytes();
+	String::from_utf8_lossy(&bytes)
+		.trim_end_matches('\0')
+		.to_string()
+}
+
+/// Get system information
+pub fn get_system_info() -> Result<SystemInfo> {
+	let cpu = detect_cpu()?;
+	let total_memory = detect_memory()?;
+	let pci_devices = detect_pci_devices()?;
+
+	Ok(SystemInfo {
+		cpu,
+		total_memory,
+		available_memory: (total_memory * 95) / 100,
+		boot_device: "Unknown".to_string(),
+		acpi_available: false, // TODO: Implement ACPI detection
+		pci_devices,
+	})
+}

kernel/src/icmp.rs

@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! ICMP (Internet Control Message Protocol) implementation.
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u8)]
+pub enum IcmpType {
+	EchoReply = 0,
+	EchoRequest = 8,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u8)]
+pub enum IcmpCode {
+	Echo = 0,
+}
+
+use alloc::vec::Vec;
+
+#[derive(Debug, Clone, Copy)]
+#[repr(C, packed)]
+pub struct IcmpPacket {
+	pub icmp_type: IcmpType,
+	pub icmp_code: IcmpCode,
+	pub checksum: u16,
+	pub identifier: u16,
+	pub sequence_number: u16,
+}
+
+impl IcmpPacket {
+	pub fn to_bytes(&self) -> Vec<u8> {
+		let mut bytes = Vec::new();
+		bytes.push(self.icmp_type as u8);
+		bytes.push(self.icmp_code as u8);
+		bytes.extend_from_slice(&self.checksum.to_be_bytes());
+		bytes.extend_from_slice(&self.identifier.to_be_bytes());
+		bytes.extend_from_slice(&self.sequence_number.to_be_bytes());
+		bytes
+	}
+}

kernel/src/init.rs

@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel initialization
+
+use crate::error::Result;
+
+/// Early kernel initialization
+pub fn early_init() {
+	crate::console::write_str("[+] Early initialization complete\n");
+}
+
+/// Initialize all kernel subsystems
+fn init_subsystems() {
+	crate::console::write_str("[*] Initializing kernel subsystems...\n");
+
+	// Initialize timer system
+	crate::console::write_str("    - Timer system\n");
+	if let Err(_e) = crate::timer::init_timer() {
+		crate::console::write_str("      [!] Timer init failed (non-fatal)\n");
+	}
+
+	// Initialize interrupt handlers
+	crate::console::write_str("    - Interrupt handlers\n");
+	if let Err(_e) = crate::interrupt::init() {
+		crate::console::write_str("      [!] Interrupt init failed (non-fatal)\n");
+	}
+
+	// Initialize scheduler
+	crate::console::write_str("    - Scheduler\n");
+	if let Err(_e) = crate::enhanced_scheduler::init_enhanced_scheduler() {
+		crate::console::write_str("      [!] Scheduler init failed (non-fatal)\n");
+	}
+
+	// Initialize IPC subsystem
+	crate::console::write_str("    - IPC subsystem\n");
+	if let Err(_e) = crate::ipc::init_ipc() {
+		crate::console::write_str("      [!] IPC init failed (non-fatal)\n");
+	}
+
+	// Initialize performance monitoring
+	crate::console::write_str("    - Performance monitoring\n");
+	if let Err(_e) = crate::advanced_perf::init_performance_monitoring() {
+		crate::console::write_str("      [!] Perf init failed (non-fatal)\n");
+	}
+
+	// Initialize diagnostics
+	crate::console::write_str("    - System diagnostics\n");
+	if let Err(_e) = crate::diagnostics::init_diagnostics() {
+		crate::console::write_str("      [!] Diagnostics init failed (non-fatal)\n");
+	}
+
+	// Initialize working task manager
+	crate::console::write_str("    - Task manager\n");
+	if let Err(_e) = crate::working_task::init_task_management() {
+		crate::console::write_str("      [!] Task mgmt init failed (non-fatal)\n");
+	}
+
+	crate::console::write_str("[+] Subsystems initialized\n");
+}
+
+/// Main kernel initialization  
+pub fn main_init() -> ! {
+	// Print boot banner
+	crate::console::write_str("\n");
+	crate::console::write_str("========================================\n");
+	crate::console::write_str("         Rust Kernel v0.1.0\n");
+	crate::console::write_str("========================================\n");
+	crate::console::write_str("\n");
+
+	// Initialize subsystems
+	init_subsystems();
+
+	// Print system information
+	crate::console::write_str("\n");
+	crate::console::write_str("System Information:\n");
+	crate::console::write_str("  Architecture: x86_64\n");
+	crate::console::write_str("  Memory mapping: 0-1GB identity mapped\n");
+	crate::console::write_str("  Page size: 2MB (large pages)\n");
+	crate::console::write_str("\n");
+	crate::console::write_str("[+] Kernel initialization complete\n");
+	crate::console::write_str("\n");
+
+	// Enter main kernel loop
+	main_kernel_loop()
+}
+
+/// Main kernel loop with task scheduling
+fn main_kernel_loop() -> ! {
+	crate::console::write_str("Entering kernel main loop...\n");
+
+	let mut tick_count: u64 = 0;
+
+	loop {
+		tick_count = tick_count.wrapping_add(1);
+
+		// Handle timer tick periodically
+		if tick_count % 10000 == 0 {
+			crate::timer::handle_timer_tick();
+		}
+
+		// Schedule next task
+		if let Some(_tid) = crate::enhanced_scheduler::schedule_next() {
+			// Task would be executed here
+			for _ in 0..100 {
+				unsafe { core::arch::asm!("pause"); }
+			}
+		}
+
+		// Cleanup terminated tasks periodically
+		if tick_count % 100000 == 0 {
+			crate::working_task::cleanup_tasks();
+		}
+
+		// Heartbeat indicator
+		if tick_count % 5_000_000 == 0 {
+			crate::console::write_str(".");
+		}
+
+		// Halt CPU to save power
+		unsafe { core::arch::asm!("hlt"); }
+	}
+}

kernel/src/interrupt.rs

@@ -0,0 +1,465 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Interrupt handling compatible with Linux kernel
+
+use alloc::{boxed::Box, collections::BTreeMap}; // Add Box import
+use core::arch::asm;
+use core::fmt;
+use core::sync::atomic::{AtomicU64, Ordering};
+
+use crate::error::{Error, Result};
+use crate::sync::Spinlock;
+
+/// Global interrupt counter
+static INTERRUPT_COUNT: AtomicU64 = AtomicU64::new(0);
+
+/// Get total interrupt count
+pub fn get_interrupt_count() -> u64 {
+	INTERRUPT_COUNT.load(Ordering::Relaxed)
+}
+
+/// Increment interrupt counter
+pub fn increment_interrupt_count() {
+	INTERRUPT_COUNT.fetch_add(1, Ordering::Relaxed);
+}
+
+/// IRQ flags - compatible with Linux kernel
+pub mod irq_flags {
+	pub const IRQF_SHARED: u32 = 0x00000080;
+	pub const IRQF_TRIGGER_NONE: u32 = 0x00000000;
+	pub const IRQF_TRIGGER_RISING: u32 = 0x00000001;
+	pub const IRQF_TRIGGER_FALLING: u32 = 0x00000002;
+	pub const IRQF_TRIGGER_HIGH: u32 = 0x00000004;
+	pub const IRQF_TRIGGER_LOW: u32 = 0x00000008;
+	pub const IRQF_ONESHOT: u32 = 0x00002000;
+	pub const IRQF_NO_SUSPEND: u32 = 0x00004000;
+	pub const IRQF_FORCE_RESUME: u32 = 0x00008000;
+	pub const IRQF_NO_THREAD: u32 = 0x00010000;
+	pub const IRQF_EARLY_RESUME: u32 = 0x00020000;
+	pub const IRQF_COND_SUSPEND: u32 = 0x00040000;
+}
+
+/// Interrupt return values - Linux compatible
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum IrqReturn {
+	None,       // IRQ_NONE
+	Handled,    // IRQ_HANDLED
+	WakeThread, // IRQ_WAKE_THREAD
+}
+
+impl fmt::Display for IrqReturn {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		match self {
+			IrqReturn::None => write!(f, "IRQ_NONE"),
+			IrqReturn::Handled => write!(f, "IRQ_HANDLED"),
+			IrqReturn::WakeThread => write!(f, "IRQ_WAKE_THREAD"),
+		}
+	}
+}
+
+/// Interrupt handler function type - Linux compatible
+pub type IrqHandler = fn(irq: u32, dev_id: *mut u8) -> IrqReturn;
+
+/// A wrapper for device pointer that can be safely shared between threads
+/// In kernel code, we know the device pointer is valid for the lifetime of the
+/// driver
+#[derive(Debug)]
+pub struct DevicePointer(*mut u8);
+
+impl DevicePointer {
+	pub fn new(ptr: *mut u8) -> Self {
+		Self(ptr)
+	}
+
+	pub fn as_ptr(&self) -> *mut u8 {
+		self.0
+	}
+}
+
+// SAFETY: In kernel code, device pointers are managed by the kernel
+// and are valid for the lifetime of the driver registration
+unsafe impl Send for DevicePointer {}
+unsafe impl Sync for DevicePointer {}
+
+/// Interrupt action structure - similar to Linux irqaction
+#[derive(Debug)]
+pub struct IrqAction {
+	pub handler: IrqHandler,
+	pub flags: u32,
+	pub name: &'static str,
+	pub dev_id: DevicePointer,
+	pub next: Option<Box<IrqAction>>,
+}
+
+impl IrqAction {
+	pub fn new(handler: IrqHandler, flags: u32, name: &'static str, dev_id: *mut u8) -> Self {
+		Self {
+			handler,
+			flags,
+			name,
+			dev_id: DevicePointer::new(dev_id),
+			next: None,
+		}
+	}
+}
+
+/// Interrupt descriptor - similar to Linux irq_desc
+#[derive(Debug)]
+pub struct IrqDescriptor {
+	pub irq: u32,
+	pub action: Option<Box<IrqAction>>,
+	pub depth: u32,          // nesting depth for disable/enable
+	pub wake_depth: u32,     // wake nesting depth
+	pub irq_count: u64,      // number of interrupts
+	pub irqs_unhandled: u64, // number of unhandled interrupts
+	pub name: &'static str,
+	pub status: u32,
+}
+
+impl IrqDescriptor {
+	pub fn new(irq: u32, name: &'static str) -> Self {
+		Self {
+			irq,
+			action: None,
+			depth: 1, // starts disabled
+			wake_depth: 0,
+			irq_count: 0,
+			irqs_unhandled: 0,
+			name,
+			status: 0,
+		}
+	}
+
+	pub fn is_enabled(&self) -> bool {
+		self.depth == 0
+	}
+
+	pub fn enable(&mut self) {
+		if self.depth > 0 {
+			self.depth -= 1;
+		}
+	}
+
+	pub fn disable(&mut self) {
+		self.depth += 1;
+	}
+}
+
+/// Global interrupt subsystem
+static INTERRUPT_SUBSYSTEM: Spinlock<InterruptSubsystem> = Spinlock::new(InterruptSubsystem::new());
+
+/// Interrupt subsystem state
+struct InterruptSubsystem {
+	descriptors: BTreeMap<u32, IrqDescriptor>,
+	enabled: bool,
+}
+
+impl InterruptSubsystem {
+	const fn new() -> Self {
+		Self {
+			descriptors: BTreeMap::new(),
+			enabled: false,
+		}
+	}
+
+	fn add_descriptor(&mut self, desc: IrqDescriptor) {
+		let irq = desc.irq;
+		self.descriptors.insert(irq, desc);
+	}
+
+	fn get_descriptor_mut(&mut self, irq: u32) -> Option<&mut IrqDescriptor> {
+		self.descriptors.get_mut(&irq)
+	}
+
+	#[allow(dead_code)]
+	fn get_descriptor(&self, irq: u32) -> Option<&IrqDescriptor> {
+		self.descriptors.get(&irq)
+	}
+}
+
+/// Initialize interrupt handling
+pub fn init() -> Result<()> {
+	let mut subsystem = INTERRUPT_SUBSYSTEM.lock();
+
+	// Initialize architecture-specific interrupt handling
+	crate::arch::x86_64::gdt::init();
+	crate::arch::x86_64::idt::init();
+
+	// Set up standard x86 interrupt vectors
+	init_standard_interrupts(&mut subsystem)?;
+
+	// Initialize interrupt controller (PIC/APIC)
+	init_interrupt_controller()?;
+
+	subsystem.enabled = true;
+	crate::info!("Interrupt subsystem initialized");
+
+	Ok(())
+}
+
+/// Initialize standard x86 interrupts
+fn init_standard_interrupts(subsystem: &mut InterruptSubsystem) -> Result<()> {
+	// Timer interrupt (IRQ 0)
+	let timer_desc = IrqDescriptor::new(0, "timer");
+	subsystem.add_descriptor(timer_desc);
+
+	// Keyboard interrupt (IRQ 1)
+	let keyboard_desc = IrqDescriptor::new(1, "keyboard");
+	subsystem.add_descriptor(keyboard_desc);
+
+	// Cascade for slave PIC (IRQ 2)
+	let cascade_desc = IrqDescriptor::new(2, "cascade");
+	subsystem.add_descriptor(cascade_desc);
+
+	// Serial port 2/4 (IRQ 3)
+	let serial_desc = IrqDescriptor::new(3, "serial");
+	subsystem.add_descriptor(serial_desc);
+
+	// Serial port 1/3 (IRQ 4)
+	let serial2_desc = IrqDescriptor::new(4, "serial");
+	subsystem.add_descriptor(serial2_desc);
+
+	// Parallel port (IRQ 7)
+	let parallel_desc = IrqDescriptor::new(7, "parallel");
+	subsystem.add_descriptor(parallel_desc);
+
+	// Real-time clock (IRQ 8)
+	let rtc_desc = IrqDescriptor::new(8, "rtc");
+	subsystem.add_descriptor(rtc_desc);
+
+	// Mouse (IRQ 12)
+	let mouse_desc = IrqDescriptor::new(12, "mouse");
+	subsystem.add_descriptor(mouse_desc);
+
+	// IDE primary (IRQ 14)
+	let ide1_desc = IrqDescriptor::new(14, "ide");
+	subsystem.add_descriptor(ide1_desc);
+
+	// IDE secondary (IRQ 15)
+	let ide2_desc = IrqDescriptor::new(15, "ide");
+	subsystem.add_descriptor(ide2_desc);
+
+	Ok(())
+}
+
+/// Initialize interrupt controller
+fn init_interrupt_controller() -> Result<()> {
+	// TODO: Initialize PIC or APIC
+	// For now, just set up basic PIC configuration
+	unsafe {
+		// Remap PIC interrupts to avoid conflicts with CPU exceptions
+		crate::arch::x86_64::pic::init_pic();
+	}
+	Ok(())
+}
+
+/// Initialize exception handlers
+fn init_exception_handlers() -> Result<()> {
+	// Architecture-specific IDT initialization is done in init()
+	Ok(())
+}
+
+/// Register an interrupt handler - Linux compatible
+pub fn request_irq(
+	irq: u32,
+	handler: IrqHandler,
+	flags: u32,
+	name: &'static str,
+	dev_id: *mut u8,
+) -> Result<()> {
+	let mut subsystem = INTERRUPT_SUBSYSTEM.lock();
+
+	if let Some(desc) = subsystem.get_descriptor_mut(irq) {
+		let action = IrqAction::new(handler, flags, name, dev_id);
+
+		// Check if IRQ is shared
+		if flags & irq_flags::IRQF_SHARED != 0 {
+			// Add to action chain
+			let mut current = &mut desc.action;
+			while let Some(ref mut act) = current {
+				current = &mut act.next;
+			}
+			*current = Some(Box::new(action));
+		} else {
+			// Replace existing action
+			desc.action = Some(Box::new(action));
+		}
+
+		// Enable the interrupt
+		desc.enable();
+
+		crate::info!("Registered IRQ {} handler: {}", irq, name);
+		Ok(())
+	} else {
+		Err(Error::InvalidArgument)
+	}
+}
+
+/// Unregister an interrupt handler - Linux compatible
+pub fn free_irq(irq: u32, dev_id: *mut u8) -> Result<()> {
+	let mut subsystem = INTERRUPT_SUBSYSTEM.lock();
+
+	if let Some(desc) = subsystem.get_descriptor_mut(irq) {
+		// Remove action with matching dev_id
+		let prev: Option<&mut Box<IrqAction>> = None;
+		let current = &mut desc.action;
+		let mut found = false;
+
+		// Handle first element specially
+		if let Some(ref mut action) = current {
+			if action.dev_id.as_ptr() == dev_id {
+				*current = action.next.take();
+				found = true;
+			} else {
+				// Search in the chain
+				let mut node = current.as_mut().unwrap();
+				while let Some(ref mut next_action) = node.next {
+					if next_action.dev_id.as_ptr() == dev_id {
+						node.next = next_action.next.take();
+						found = true;
+						break;
+					}
+					node = node.next.as_mut().unwrap();
+				}
+			}
+		}
+
+		if found {
+			// If no more actions, disable the interrupt
+			if desc.action.is_none() {
+				desc.disable();
+			}
+
+			crate::info!("Freed IRQ {} handler", irq);
+			Ok(())
+		} else {
+			Err(Error::NotFound)
+		}
+	} else {
+		Err(Error::InvalidArgument)
+	}
+}
+
+/// Enable interrupts globally
+pub fn enable() {
+	#[cfg(target_arch = "x86_64")]
+	unsafe {
+		core::arch::asm!("sti");
+	}
+}
+
+/// Disable interrupts globally
+pub fn disable() {
+	#[cfg(target_arch = "x86_64")]
+	unsafe {
+		core::arch::asm!("cli");
+	}
+}
+
+/// Enable a specific interrupt line
+pub fn enable_irq(irq: u32) -> Result<()> {
+	let mut subsystem = INTERRUPT_SUBSYSTEM.lock();
+
+	if let Some(desc) = subsystem.get_descriptor_mut(irq) {
+		desc.enable();
+		crate::debug!("Enabled IRQ {}", irq);
+		Ok(())
+	} else {
+		Err(Error::InvalidArgument)
+	}
+}
+
+/// Disable a specific interrupt line
+pub fn disable_irq(irq: u32) -> Result<()> {
+	let mut subsystem = INTERRUPT_SUBSYSTEM.lock();
+
+	if let Some(desc) = subsystem.get_descriptor_mut(irq) {
+		desc.disable();
+		crate::debug!("Disabled IRQ {}", irq);
+		Ok(())
+	} else {
+		Err(Error::InvalidArgument)
+	}
+}
+
+/// Register an interrupt handler at a specific vector
+pub fn register_interrupt_handler(vector: u32, handler: usize) -> Result<()> {
+	if vector > 255 {
+		return Err(Error::InvalidArgument);
+	}
+
+	crate::info!(
+		"Registered interrupt handler at vector 0x{:x} -> 0x{:x}",
+		vector,
+		handler
+	);
+	Ok(())
+}
+
+// Exception handlers
+/// System call interrupt handler
+#[no_mangle]
+pub extern "C" fn syscall_handler() {
+	// TODO: Get syscall arguments from registers
+	// In x86_64, syscall arguments are passed in:
+	// rax = syscall number
+	// rdi = arg0, rsi = arg1, rdx = arg2, r10 = arg3, r8 = arg4, r9 = arg5
+
+	let mut syscall_num: u64;
+	let mut arg0: u64;
+	let mut arg1: u64;
+	let mut arg2: u64;
+	let mut arg3: u64;
+	let mut arg4: u64;
+	let mut arg5: u64;
+
+	unsafe {
+		core::arch::asm!(
+		    "mov {0}, rax",
+		    "mov {1}, rdi",
+		    "mov {2}, rsi",
+		    "mov {3}, rdx",
+		    "mov {4}, r10",
+		    "mov {5}, r8",
+		    "mov {6}, r9",
+		    out(reg) syscall_num,
+		    out(reg) arg0,
+		    out(reg) arg1,
+		    out(reg) arg2,
+		    out(reg) arg3,
+		    out(reg) arg4,
+		    out(reg) arg5,
+		);
+	}
+
+	// Call syscall dispatcher
+	let result = crate::syscalls::arch::syscall_entry(
+		syscall_num,
+		arg0,
+		arg1,
+		arg2,
+		arg3,
+		arg4,
+		arg5,
+	);
+
+	// Return result in register (rax)
+	unsafe {
+		core::arch::asm!(
+		    "mov rax, {0}",
+		    in(reg) result,
+		);
+
+		// Return from interrupt
+		core::arch::asm!("iretq", options(noreturn));
+	}
+}
+
+/// Install syscall interrupt handler
+pub fn install_syscall_handler() -> Result<()> {
+	// Install at interrupt vector 0x80 (traditional Linux syscall vector)
+	register_interrupt_handler(0x80, syscall_handler as usize)?;
+
+	// TODO: Also set up SYSCALL/SYSRET for x86_64
+	Ok(())
+}

kernel/src/ipc.rs

@@ -0,0 +1,482 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Advanced Inter-Process Communication (IPC) system
+
+use alloc::{
+	collections::{BTreeMap, VecDeque},
+	string::String,
+	vec::Vec,
+};
+use core::sync::atomic::{AtomicU64, Ordering};
+
+use crate::error::{Error, Result};
+use crate::sync::Spinlock;
+use crate::types::Tid;
+
+/// IPC message types
+#[derive(Debug, Clone, PartialEq)]
+pub enum MessageType {
+	Data,
+	Signal,
+	Request,
+	Response,
+	Broadcast,
+	Priority,
+}
+
+/// IPC message structure
+#[derive(Debug, Clone)]
+pub struct Message {
+	pub id: u64,
+	pub sender: Tid,
+	pub recipient: Tid,
+	pub msg_type: MessageType,
+	pub data: Vec<u8>,
+	pub timestamp: u64,
+	pub priority: u8,
+}
+
+/// Message queue for a process
+#[derive(Debug)]
+pub struct MessageQueue {
+	pub messages: VecDeque<Message>,
+	pub max_size: usize,
+	pub blocked_senders: Vec<Tid>,
+	pub blocked_receivers: Vec<Tid>,
+}
+
+impl MessageQueue {
+	pub fn new(max_size: usize) -> Self {
+		Self {
+			messages: VecDeque::new(),
+			max_size,
+			blocked_senders: Vec::new(),
+			blocked_receivers: Vec::new(),
+		}
+	}
+
+	pub fn is_full(&self) -> bool {
+		self.messages.len() >= self.max_size
+	}
+
+	pub fn is_empty(&self) -> bool {
+		self.messages.is_empty()
+	}
+}
+
+/// Semaphore for synchronization
+#[derive(Debug)]
+pub struct Semaphore {
+	pub value: i32,
+	pub waiting_tasks: VecDeque<Tid>,
+}
+
+impl Semaphore {
+	pub fn new(initial_value: i32) -> Self {
+		Self {
+			value: initial_value,
+			waiting_tasks: VecDeque::new(),
+		}
+	}
+}
+
+/// Shared memory region
+#[derive(Debug)]
+pub struct SharedMemory {
+	pub id: u64,
+	pub size: usize,
+	pub address: usize,
+	pub owners: Vec<Tid>,
+	pub permissions: u32,
+	pub ref_count: usize,
+}
+
+/// IPC statistics
+#[derive(Debug, Default)]
+pub struct IpcStats {
+	pub messages_sent: AtomicU64,
+	pub messages_received: AtomicU64,
+	pub semaphore_operations: AtomicU64,
+	pub shared_memory_attachments: AtomicU64,
+	pub pipe_operations: AtomicU64,
+}
+
+/// Advanced IPC manager
+pub struct IpcManager {
+	message_queues: Spinlock<BTreeMap<Tid, MessageQueue>>,
+	semaphores: Spinlock<BTreeMap<u64, Semaphore>>,
+	shared_memory: Spinlock<BTreeMap<u64, SharedMemory>>,
+	pipes: Spinlock<BTreeMap<u64, VecDeque<u8>>>,
+	next_message_id: AtomicU64,
+	next_semaphore_id: AtomicU64,
+	next_shm_id: AtomicU64,
+	next_pipe_id: AtomicU64,
+	stats: IpcStats,
+}
+
+impl IpcManager {
+	pub const fn new() -> Self {
+		Self {
+			message_queues: Spinlock::new(BTreeMap::new()),
+			semaphores: Spinlock::new(BTreeMap::new()),
+			shared_memory: Spinlock::new(BTreeMap::new()),
+			pipes: Spinlock::new(BTreeMap::new()),
+			next_message_id: AtomicU64::new(1),
+			next_semaphore_id: AtomicU64::new(1),
+			next_shm_id: AtomicU64::new(1),
+			next_pipe_id: AtomicU64::new(1),
+			stats: IpcStats {
+				messages_sent: AtomicU64::new(0),
+				messages_received: AtomicU64::new(0),
+				semaphore_operations: AtomicU64::new(0),
+				shared_memory_attachments: AtomicU64::new(0),
+				pipe_operations: AtomicU64::new(0),
+			},
+		}
+	}
+
+	/// Create message queue for a process
+	pub fn create_message_queue(&self, tid: Tid, max_size: usize) -> Result<()> {
+		let mut queues = self.message_queues.lock();
+		if queues.contains_key(&tid) {
+			return Err(Error::AlreadyExists);
+		}
+		queues.insert(tid, MessageQueue::new(max_size));
+		Ok(())
+	}
+
+	/// Send message to another process
+	pub fn send_message(
+		&self,
+		sender: Tid,
+		recipient: Tid,
+		msg_type: MessageType,
+		data: Vec<u8>,
+		priority: u8,
+	) -> Result<u64> {
+		let message_id = self.next_message_id.fetch_add(1, Ordering::Relaxed);
+		let message = Message {
+			id: message_id,
+			sender,
+			recipient,
+			msg_type,
+			data,
+			timestamp: crate::time::get_jiffies().0,
+			priority,
+		};
+
+		let mut queues = self.message_queues.lock();
+		match queues.get_mut(&recipient) {
+			Some(queue) => {
+				if queue.is_full() {
+					// Queue is full, block sender or return error
+					return Err(Error::ResourceBusy);
+				}
+
+				// Insert message in priority order
+				let insert_pos = queue
+					.messages
+					.iter()
+					.position(|m| m.priority < priority)
+					.unwrap_or(queue.messages.len());
+				queue.messages.insert(insert_pos, message);
+
+				self.stats.messages_sent.fetch_add(1, Ordering::Relaxed);
+				Ok(message_id)
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Receive message from queue
+	pub fn receive_message(&self, tid: Tid) -> Result<Option<Message>> {
+		let mut queues = self.message_queues.lock();
+		match queues.get_mut(&tid) {
+			Some(queue) => {
+				if let Some(message) = queue.messages.pop_front() {
+					self.stats
+						.messages_received
+						.fetch_add(1, Ordering::Relaxed);
+					Ok(Some(message))
+				} else {
+					Ok(None)
+				}
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Create semaphore
+	pub fn create_semaphore(&self, initial_value: i32) -> Result<u64> {
+		let sem_id = self.next_semaphore_id.fetch_add(1, Ordering::Relaxed);
+		let mut semaphores = self.semaphores.lock();
+		semaphores.insert(sem_id, Semaphore::new(initial_value));
+		Ok(sem_id)
+	}
+
+	/// Wait on semaphore (P operation)
+	pub fn semaphore_wait(&self, sem_id: u64, tid: Tid) -> Result<bool> {
+		let mut semaphores = self.semaphores.lock();
+		match semaphores.get_mut(&sem_id) {
+			Some(semaphore) => {
+				if semaphore.value > 0 {
+					semaphore.value -= 1;
+					self.stats
+						.semaphore_operations
+						.fetch_add(1, Ordering::Relaxed);
+					Ok(true) // Acquired immediately
+				} else {
+					semaphore.waiting_tasks.push_back(tid);
+					Ok(false) // Would block
+				}
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Signal semaphore (V operation)
+	pub fn semaphore_signal(&self, sem_id: u64) -> Result<Option<Tid>> {
+		let mut semaphores = self.semaphores.lock();
+		match semaphores.get_mut(&sem_id) {
+			Some(semaphore) => {
+				semaphore.value += 1;
+				let woken_task = semaphore.waiting_tasks.pop_front();
+				if woken_task.is_some() {
+					semaphore.value -= 1; // Task will consume the signal
+				}
+				self.stats
+					.semaphore_operations
+					.fetch_add(1, Ordering::Relaxed);
+				Ok(woken_task)
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Create shared memory region
+	pub fn create_shared_memory(&self, size: usize, permissions: u32) -> Result<u64> {
+		let shm_id = self.next_shm_id.fetch_add(1, Ordering::Relaxed);
+
+		// Allocate memory (simplified - in reality would use page allocator)
+		let address = crate::memory::kmalloc::kmalloc(size)?;
+
+		let shm = SharedMemory {
+			id: shm_id,
+			size,
+			address: address as usize,
+			owners: Vec::new(),
+			permissions,
+			ref_count: 0,
+		};
+
+		let mut shared_memory = self.shared_memory.lock();
+		shared_memory.insert(shm_id, shm);
+		Ok(shm_id)
+	}
+
+	/// Attach to shared memory
+	pub fn attach_shared_memory(&self, shm_id: u64, tid: Tid) -> Result<usize> {
+		let mut shared_memory = self.shared_memory.lock();
+		match shared_memory.get_mut(&shm_id) {
+			Some(shm) => {
+				if !shm.owners.contains(&tid) {
+					shm.owners.push(tid);
+					shm.ref_count += 1;
+				}
+				self.stats
+					.shared_memory_attachments
+					.fetch_add(1, Ordering::Relaxed);
+				Ok(shm.address)
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Create pipe
+	pub fn create_pipe(&self) -> Result<u64> {
+		let pipe_id = self.next_pipe_id.fetch_add(1, Ordering::Relaxed);
+		let mut pipes = self.pipes.lock();
+		pipes.insert(pipe_id, VecDeque::new());
+		Ok(pipe_id)
+	}
+
+	/// Write to pipe
+	pub fn pipe_write(&self, pipe_id: u64, data: &[u8]) -> Result<usize> {
+		let mut pipes = self.pipes.lock();
+		match pipes.get_mut(&pipe_id) {
+			Some(pipe) => {
+				pipe.extend(data.iter().cloned());
+				self.stats.pipe_operations.fetch_add(1, Ordering::Relaxed);
+				Ok(data.len())
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Read from pipe  
+	pub fn pipe_read(&self, pipe_id: u64, buffer: &mut [u8]) -> Result<usize> {
+		let mut pipes = self.pipes.lock();
+		match pipes.get_mut(&pipe_id) {
+			Some(pipe) => {
+				let read_len = buffer.len().min(pipe.len());
+				for i in 0..read_len {
+					buffer[i] = pipe.pop_front().unwrap();
+				}
+				self.stats.pipe_operations.fetch_add(1, Ordering::Relaxed);
+				Ok(read_len)
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Get IPC statistics
+	pub fn get_stats(&self) -> IpcStatsSnapshot {
+		IpcStatsSnapshot {
+			messages_sent: self.stats.messages_sent.load(Ordering::Relaxed),
+			messages_received: self.stats.messages_received.load(Ordering::Relaxed),
+			semaphore_operations: self
+				.stats
+				.semaphore_operations
+				.load(Ordering::Relaxed),
+			shared_memory_attachments: self
+				.stats
+				.shared_memory_attachments
+				.load(Ordering::Relaxed),
+			pipe_operations: self.stats.pipe_operations.load(Ordering::Relaxed),
+			active_queues: self.message_queues.lock().len(),
+			active_semaphores: self.semaphores.lock().len(),
+			active_shared_memory: self.shared_memory.lock().len(),
+			active_pipes: self.pipes.lock().len(),
+		}
+	}
+
+	/// Cleanup resources for a terminated process
+	pub fn cleanup_process(&self, tid: Tid) -> Result<()> {
+		// Remove message queue
+		self.message_queues.lock().remove(&tid);
+
+		// Remove from semaphore waiting lists
+		let mut semaphores = self.semaphores.lock();
+		for semaphore in semaphores.values_mut() {
+			semaphore.waiting_tasks.retain(|&t| t != tid);
+		}
+
+		// Detach from shared memory
+		let mut shared_memory = self.shared_memory.lock();
+		let mut to_remove = Vec::new();
+		for (id, shm) in shared_memory.iter_mut() {
+			if let Some(pos) = shm.owners.iter().position(|&t| t == tid) {
+				shm.owners.remove(pos);
+				shm.ref_count -= 1;
+				if shm.ref_count == 0 {
+					to_remove.push(*id);
+				}
+			}
+		}
+
+		// Free unused shared memory
+		for id in to_remove {
+			if let Some(shm) = shared_memory.remove(&id) {
+				unsafe {
+					crate::memory::kmalloc::kfree(shm.address as *mut u8);
+				}
+			}
+		}
+
+		Ok(())
+	}
+}
+
+/// IPC statistics snapshot
+#[derive(Debug, Clone)]
+pub struct IpcStatsSnapshot {
+	pub messages_sent: u64,
+	pub messages_received: u64,
+	pub semaphore_operations: u64,
+	pub shared_memory_attachments: u64,
+	pub pipe_operations: u64,
+	pub active_queues: usize,
+	pub active_semaphores: usize,
+	pub active_shared_memory: usize,
+	pub active_pipes: usize,
+}
+
+/// Global IPC manager
+static IPC_MANAGER: IpcManager = IpcManager::new();
+
+/// Initialize IPC system
+pub fn init_ipc() -> Result<()> {
+	crate::info!("IPC system initialized");
+	Ok(())
+}
+
+/// Create message queue for process
+pub fn create_message_queue(tid: Tid, max_size: usize) -> Result<()> {
+	IPC_MANAGER.create_message_queue(tid, max_size)
+}
+
+/// Send message
+pub fn send_message(
+	sender: Tid,
+	recipient: Tid,
+	msg_type: MessageType,
+	data: Vec<u8>,
+	priority: u8,
+) -> Result<u64> {
+	IPC_MANAGER.send_message(sender, recipient, msg_type, data, priority)
+}
+
+/// Receive message
+pub fn receive_message(tid: Tid) -> Result<Option<Message>> {
+	IPC_MANAGER.receive_message(tid)
+}
+
+/// Create semaphore
+pub fn create_semaphore(initial_value: i32) -> Result<u64> {
+	IPC_MANAGER.create_semaphore(initial_value)
+}
+
+/// Wait on semaphore
+pub fn semaphore_wait(sem_id: u64, tid: Tid) -> Result<bool> {
+	IPC_MANAGER.semaphore_wait(sem_id, tid)
+}
+
+/// Signal semaphore
+pub fn semaphore_signal(sem_id: u64) -> Result<Option<Tid>> {
+	IPC_MANAGER.semaphore_signal(sem_id)
+}
+
+/// Create shared memory
+pub fn create_shared_memory(size: usize, permissions: u32) -> Result<u64> {
+	IPC_MANAGER.create_shared_memory(size, permissions)
+}
+
+/// Attach to shared memory
+pub fn attach_shared_memory(shm_id: u64, tid: Tid) -> Result<usize> {
+	IPC_MANAGER.attach_shared_memory(shm_id, tid)
+}
+
+/// Create pipe
+pub fn create_pipe() -> Result<u64> {
+	IPC_MANAGER.create_pipe()
+}
+
+/// Write to pipe
+pub fn pipe_write(pipe_id: u64, data: &[u8]) -> Result<usize> {
+	IPC_MANAGER.pipe_write(pipe_id, data)
+}
+
+/// Read from pipe
+pub fn pipe_read(pipe_id: u64, buffer: &mut [u8]) -> Result<usize> {
+	IPC_MANAGER.pipe_read(pipe_id, buffer)
+}
+
+/// Get IPC statistics
+pub fn get_ipc_stats() -> IpcStatsSnapshot {
+	IPC_MANAGER.get_stats()
+}
+
+/// Cleanup process IPC resources
+pub fn cleanup_process_ipc(tid: Tid) -> Result<()> {
+	IPC_MANAGER.cleanup_process(tid)
+}

kernel/src/kthread.rs

@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel thread management
+
+use alloc::{boxed::Box, string::String, vec::Vec};
+use core::sync::atomic::{AtomicU32, Ordering};
+
+use crate::error::Result;
+use crate::sync::Spinlock;
+use crate::{error, info};
+
+/// Kernel thread ID
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct KthreadId(u32);
+
+/// Kernel thread state
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum KthreadState {
+	Running,
+	Sleeping,
+	Stopped,
+	Dead,
+}
+
+/// Kernel thread function type
+pub type KthreadFn = fn();
+
+/// Kernel thread descriptor
+#[derive(Debug)]
+pub struct Kthread {
+	pub id: KthreadId,
+	pub name: String,
+	pub state: KthreadState,
+	pub function: KthreadFn,
+	// TODO: Add stack pointer, register context, etc.
+}
+
+impl Kthread {
+	pub fn new(id: KthreadId, name: String, function: KthreadFn) -> Self {
+		Self {
+			id,
+			name,
+			state: KthreadState::Running,
+			function,
+		}
+	}
+}
+
+/// Global kernel thread manager
+static KTHREAD_MANAGER: Spinlock<KthreadManager> = Spinlock::new(KthreadManager::new());
+static NEXT_KTHREAD_ID: AtomicU32 = AtomicU32::new(1);
+
+/// Kernel thread manager
+struct KthreadManager {
+	threads: Vec<Kthread>,
+}
+
+impl KthreadManager {
+	const fn new() -> Self {
+		Self {
+			threads: Vec::new(),
+		}
+	}
+
+	fn spawn(&mut self, name: String, function: KthreadFn) -> KthreadId {
+		let id = KthreadId(NEXT_KTHREAD_ID.fetch_add(1, Ordering::SeqCst));
+		let thread = Kthread::new(id, name, function);
+
+		self.threads.push(thread);
+		id
+	}
+
+	fn get_thread(&self, id: KthreadId) -> Option<&Kthread> {
+		self.threads.iter().find(|t| t.id == id)
+	}
+
+	fn get_thread_mut(&mut self, id: KthreadId) -> Option<&mut Kthread> {
+		self.threads.iter_mut().find(|t| t.id == id)
+	}
+}
+
+/// Spawn a new kernel thread
+pub fn kthread_run(name: &str, function: KthreadFn) -> Result<KthreadId> {
+	let mut manager = KTHREAD_MANAGER.lock();
+	let id = manager.spawn(String::from(name), function);
+
+	info!("Spawned kernel thread: {} (ID: {:?})", name, id);
+	Ok(id)
+}
+
+/// Get current thread ID (simplified - always returns kernel thread 0 for now)
+pub fn current_kthread_id() -> KthreadId {
+	KthreadId(0)
+}
+
+/// Initialize kernel thread subsystem
+pub fn init_kthreads() -> Result<()> {
+	info!("Initializing kernel thread subsystem");
+
+	// Spawn idle thread
+	kthread_run("idle", idle_thread)?;
+
+	// Spawn a test thread
+	kthread_run("test", test_thread)?;
+
+	info!("Kernel thread subsystem initialized");
+	Ok(())
+}
+
+/// Idle kernel thread - runs when no other threads are active
+fn idle_thread() {
+	info!("Idle kernel thread started");
+
+	loop {
+		// In a real implementation, this would:
+		// 1. Check for runnable threads
+		// 2. Switch to them if available
+		// 3. Otherwise, halt the CPU until interrupt
+
+		#[cfg(target_arch = "x86_64")]
+		unsafe {
+			core::arch::asm!("hlt");
+		}
+
+		#[cfg(not(target_arch = "x86_64"))]
+		core::hint::spin_loop();
+	}
+}
+
+/// Test kernel thread
+fn test_thread() {
+	info!("Test kernel thread started");
+
+	let mut counter = 0u32;
+	loop {
+		counter += 1;
+
+		if counter % 10000000 == 0 {
+			info!("Test thread tick: {}", counter);
+		}
+
+		// Simple delay
+		for _ in 0..1000 {
+			core::hint::spin_loop();
+		}
+
+		// Stop after a while to avoid spam
+		if counter > 50000000 {
+			info!("Test thread finished");
+			break;
+		}
+	}
+}
+
+/// Simple cooperative yielding (simplified scheduler)
+pub fn kthread_yield() {
+	// In a real implementation, this would:
+	// 1. Save current thread context
+	// 2. Select next runnable thread
+	// 3. Switch to it
+
+	// For now, just do nothing - we don't have real threading yet
+	core::hint::spin_loop();
+}
+
+/// Put current thread to sleep
+pub fn kthread_sleep(duration_ms: u64) {
+	// In a real implementation, this would:
+	// 1. Set thread state to sleeping
+	// 2. Set wake-up time
+	// 3. Switch to another thread
+
+	// For now, just busy wait (not efficient, but simple)
+	let target_ticks = crate::time::get_jiffies() + (duration_ms * crate::time::HZ / 1000);
+
+	while crate::time::get_jiffies().0 < target_ticks.0 {
+		core::hint::spin_loop();
+	}
+}
+
+/// Sleep for specified number of jiffies
+pub fn sleep_for_jiffies(jiffies: u64) {
+	let target_time = crate::time::get_jiffies() + jiffies;
+	while crate::time::get_jiffies().0 < target_time.0 {
+		core::hint::spin_loop();
+	}
+}
+
+/// Get current thread count for diagnostics
+pub fn get_thread_count() -> Result<usize> {
+	let manager = KTHREAD_MANAGER.lock();
+	Ok(manager.threads.len())
+}

kernel/src/lib.rs

@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! The Rust kernel crate.
+//!
+//! This crate provides the core kernel APIs and functionality for the Rust
+//! kernel. It is inspired by the Linux kernel's Rust infrastructure but
+//! designed as a standalone kernel implementation.
+
+#![no_std]
+#![feature(alloc_error_handler)]
+#![feature(panic_info_message)]
+#![feature(asm_const)]
+#![feature(const_mut_refs)]
+#![feature(custom_test_frameworks)]
+#![feature(allocator_api)]
+#![test_runner(crate::test_runner)]
+#![reexport_test_harness_main = "test_main"]
+
+extern crate alloc;
+
+// Include boot assembly
+// #[cfg(target_arch = "x86_64")]
+// global_asm!(include_str!("arch/x86_64/boot.s"), options(att_syntax));
+
+pub mod advanced_perf; // Advanced performance monitoring and profiling
+pub mod arch;
+pub mod arp;
+pub mod benchmark; // Performance benchmarking
+pub mod boot;
+pub mod console;
+pub mod cpu;
+pub mod device;
+pub mod device_advanced;
+pub mod diagnostics; // System diagnostics and health monitoring
+pub mod driver;
+pub mod drivers_init; // Driver initialization
+pub mod enhanced_scheduler; // Enhanced preemptive scheduler
+pub mod error;
+pub mod fs;
+pub mod hardware; // Hardware detection and initialization
+pub mod icmp;
+pub mod init;
+pub mod interrupt;
+pub mod ipc; // Inter-process communication
+pub mod kthread; // Kernel thread management
+pub mod logging; // Kernel logging and debugging
+pub mod memfs; // In-memory file system
+pub mod memory;
+pub mod module;
+pub mod module_loader; // Dynamic module loading
+pub mod network;
+pub mod panic;
+pub mod perf; // Performance monitoring
+pub mod prelude;
+pub mod process;
+pub mod scheduler;
+pub mod shell; // Kernel shell interface
+pub mod stress_test; // System stress testing
+pub mod sync;
+pub mod syscall;
+pub mod syscalls; // New syscall infrastructure
+pub mod sysinfo; // System information and hardware detection
+pub mod task;
+pub mod test_init; // Kernel initialization testing
+pub mod test_suite; // Comprehensive kernel test suite
+pub mod time;
+pub mod timer; // Timer interrupt and preemptive scheduling
+pub mod types;
+pub mod usermode;
+pub mod working_task; // Working kernel task implementation // User mode program support
+
+/// Kernel version information
+pub const VERSION: &str = env!("CARGO_PKG_VERSION");
+pub const NAME: &str = "Rust Kernel";
+
+/// Kernel entry point called from architecture-specific code
+/// This is called from the boot assembly with multiboot information
+#[no_mangle]
+pub extern "C" fn kernel_main() -> ! {
+	// Early initialization without memory allocation
+	early_kernel_init();
+
+	// Initialize memory management
+	if let Err(e) = memory_init() {
+		panic!("Memory initialization failed: {:?}", e);
+	}
+
+	// Now we can use allocations, continue with full initialization
+	init::early_init();
+
+	init::main_init();
+
+	// Should not return from main_init
+	panic!("kernel_main returned unexpectedly");
+}
+
+/// Kernel entry point with multiboot parameters
+#[no_mangle]
+pub extern "C" fn kernel_main_multiboot(multiboot_magic: u32, multiboot_addr: u32) -> ! {
+	// Verify multiboot magic number
+	if multiboot_magic != 0x36d76289 && multiboot_magic != 0x2BADB002 {
+		panic!("Invalid multiboot magic: 0x{:x}", multiboot_magic);
+	}
+
+	// Store multiboot information
+	boot::set_multiboot_info(multiboot_addr as usize);
+
+	// Continue with normal boot
+	kernel_main();
+}
+
+/// Early kernel initialization before memory allocator is available
+fn early_kernel_init() {
+	// Initialize console first so we can print messages
+	if let Err(_) = console::init() {
+		// Can't print error since console isn't initialized
+		loop {}
+	}
+
+	crate::console::write_str("\n");
+	crate::console::write_str("Booting Rust Kernel...\n");
+}
+
+/// Initialize memory management using multiboot information
+fn memory_init() -> Result<(), error::Error> {
+	crate::console::write_str("[*] Initializing memory subsystem...\n");
+
+	// FIXME: Multiboot parsing causes crashes - use default memory layout for now
+	memory::page::init()?;
+
+	// Initialize heap allocator
+	memory::kmalloc::init()?;
+
+	crate::console::write_str("[+] Memory subsystem ready\n");
+	Ok(())
+}
+
+/// Test runner for kernel tests
+#[cfg(test)]
+fn test_runner(tests: &[&dyn Fn()]) {
+	println!("Running {} tests", tests.len());
+	for test in tests {
+		test();
+	}
+	exit_qemu(QemuExitCode::Success);
+}
+
+#[cfg(test)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u32)]
+pub enum QemuExitCode {
+	Success = 0x10,
+	Failed = 0x11,
+}
+
+#[cfg(test)]
+pub fn exit_qemu(exit_code: QemuExitCode) {
+	use arch::x86_64::port::Port;
+
+	unsafe {
+		let mut port = Port::new(0xf4);
+		port.write(exit_code as u32);
+	}
+}
+
+/// Global allocator error handler
+#[alloc_error_handler]
+fn alloc_error_handler(layout: alloc::alloc::Layout) -> ! {
+	panic!("allocation error: {:?}", layout)
+}

kernel/src/logging.rs

@@ -0,0 +1,488 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel logging and debugging system
+
+use alloc::{format, string::String, vec, vec::Vec};
+use core::fmt::Write;
+
+use crate::error::Result;
+use crate::sync::Spinlock;
+use crate::time::get_jiffies;
+
+/// Log levels (compatible with Linux kernel)
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub enum LogLevel {
+	Emergency = 0, // KERN_EMERG
+	Alert = 1,     // KERN_ALERT
+	Critical = 2,  // KERN_CRIT
+	Error = 3,     // KERN_ERR
+	Warning = 4,   // KERN_WARNING
+	Notice = 5,    // KERN_NOTICE
+	Info = 6,      // KERN_INFO
+	Debug = 7,     // KERN_DEBUG
+}
+
+impl LogLevel {
+	pub fn as_str(&self) -> &'static str {
+		match self {
+			LogLevel::Emergency => "EMERG",
+			LogLevel::Alert => "ALERT",
+			LogLevel::Critical => "CRIT",
+			LogLevel::Error => "ERROR",
+			LogLevel::Warning => "WARN",
+			LogLevel::Notice => "NOTICE",
+			LogLevel::Info => "INFO",
+			LogLevel::Debug => "DEBUG",
+		}
+	}
+
+	pub fn color_code(&self) -> &'static str {
+		match self {
+			LogLevel::Emergency => "\x1b[95m", // Magenta
+			LogLevel::Alert => "\x1b[91m",     // Bright Red
+			LogLevel::Critical => "\x1b[31m",  // Red
+			LogLevel::Error => "\x1b[31m",     // Red
+			LogLevel::Warning => "\x1b[33m",   // Yellow
+			LogLevel::Notice => "\x1b[36m",    // Cyan
+			LogLevel::Info => "\x1b[32m",      // Green
+			LogLevel::Debug => "\x1b[37m",     // White
+		}
+	}
+}
+
+/// Log entry structure
+#[derive(Debug, Clone)]
+pub struct LogEntry {
+	pub level: LogLevel,
+	pub timestamp: u64,
+	pub cpu: u32,
+	pub pid: Option<u32>,
+	pub module: String,
+	pub message: String,
+}
+
+impl LogEntry {
+	pub fn new(level: LogLevel, module: String, message: String) -> Self {
+		Self {
+			level,
+			timestamp: get_jiffies().0,
+			cpu: 0, // TODO: Get current CPU ID
+			pid: crate::process::current_process_pid().map(|p| p.0),
+			module,
+			message,
+		}
+	}
+
+	pub fn format(&self, colored: bool) -> String {
+		let color_start = if colored { self.level.color_code() } else { "" };
+		let color_reset = if colored { "\x1b[0m" } else { "" };
+
+		format!(
+			"{}[{:>5}] [{:>10}] {} {}: {}{}\n",
+			color_start,
+			self.level.as_str(),
+			self.timestamp,
+			self.cpu,
+			self.module,
+			self.message,
+			color_reset
+		)
+	}
+}
+
+/// Debug categories for filtering
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum DebugCategory {
+	Memory,
+	Process,
+	FileSystem,
+	Network,
+	Driver,
+	Interrupt,
+	Scheduler,
+	UserMode,
+	Performance,
+	All,
+}
+
+/// Logger configuration
+#[derive(Debug)]
+pub struct LoggerConfig {
+	pub min_level: LogLevel,
+	pub max_entries: usize,
+	pub console_output: bool,
+	pub colored_output: bool,
+	pub debug_categories: Vec<DebugCategory>,
+}
+
+impl LoggerConfig {
+	pub fn new() -> Self {
+		Self {
+			min_level: LogLevel::Info,
+			max_entries: 1000,
+			console_output: true,
+			colored_output: true,
+			debug_categories: vec![DebugCategory::All],
+		}
+	}
+
+	pub fn with_level(mut self, level: LogLevel) -> Self {
+		self.min_level = level;
+		self
+	}
+
+	pub fn with_max_entries(mut self, max: usize) -> Self {
+		self.max_entries = max;
+		self
+	}
+
+	pub fn enable_category(mut self, category: DebugCategory) -> Self {
+		if !self.debug_categories.contains(&category) {
+			self.debug_categories.push(category);
+		}
+		self
+	}
+}
+
+/// Kernel logger
+pub struct KernelLogger {
+	config: LoggerConfig,
+	entries: Vec<LogEntry>,
+	stats: LogStats,
+}
+
+/// Logging statistics
+#[derive(Debug, Default)]
+pub struct LogStats {
+	pub total_entries: u64,
+	pub entries_by_level: [u64; 8], // One for each log level
+	pub dropped_entries: u64,
+}
+
+impl KernelLogger {
+	pub const fn new() -> Self {
+		Self {
+			config: LoggerConfig {
+				min_level: LogLevel::Info,
+				max_entries: 1000,
+				console_output: true,
+				colored_output: true,
+				debug_categories: Vec::new(),
+			},
+			entries: Vec::new(),
+			stats: LogStats {
+				total_entries: 0,
+				entries_by_level: [0; 8],
+				dropped_entries: 0,
+			},
+		}
+	}
+
+	pub fn init(&mut self, config: LoggerConfig) {
+		self.config = config;
+	}
+
+	pub fn log(&mut self, level: LogLevel, module: &str, message: &str) {
+		// Check if we should log this level
+		if level > self.config.min_level {
+			return;
+		}
+
+		let entry = LogEntry::new(level, module.into(), message.into());
+
+		// Update statistics
+		self.stats.total_entries += 1;
+		self.stats.entries_by_level[level as usize] += 1;
+
+		// Output to console if enabled
+		if self.config.console_output {
+			let formatted = entry.format(self.config.colored_output);
+			// Use the print macro since there's no direct write_str function
+			crate::print!("{}", formatted);
+		}
+
+		// Store in buffer
+		if self.entries.len() >= self.config.max_entries {
+			self.entries.remove(0); // Remove oldest entry
+			self.stats.dropped_entries += 1;
+		}
+		self.entries.push(entry);
+	}
+
+	pub fn get_entries(&self) -> &[LogEntry] {
+		&self.entries
+	}
+
+	pub fn get_entries_by_level(&self, level: LogLevel) -> Vec<&LogEntry> {
+		self.entries.iter().filter(|e| e.level == level).collect()
+	}
+
+	pub fn clear(&mut self) {
+		self.entries.clear();
+	}
+
+	pub fn get_stats(&self) -> &LogStats {
+		&self.stats
+	}
+
+	pub fn set_level(&mut self, level: LogLevel) {
+		self.config.min_level = level;
+	}
+
+	pub fn dump_buffer(&self) -> String {
+		let mut output = String::new();
+		for entry in &self.entries {
+			output.push_str(&entry.format(false));
+		}
+		output
+	}
+
+	pub fn generate_report(&self) -> String {
+		let mut report = String::from("Kernel Logger Report\n");
+		report.push_str("====================\n\n");
+
+		report.push_str(&format!("Configuration:\n"));
+		report.push_str(&format!("  Min Level: {:?}\n", self.config.min_level));
+		report.push_str(&format!("  Max Entries: {}\n", self.config.max_entries));
+		report.push_str(&format!(
+			"  Console Output: {}\n",
+			self.config.console_output
+		));
+		report.push_str(&format!(
+			"  Colored Output: {}\n",
+			self.config.colored_output
+		));
+
+		report.push_str(&format!("\nStatistics:\n"));
+		report.push_str(&format!("  Total Entries: {}\n", self.stats.total_entries));
+		report.push_str(&format!(
+			"  Dropped Entries: {}\n",
+			self.stats.dropped_entries
+		));
+		report.push_str(&format!("  Current Buffer Size: {}\n", self.entries.len()));
+
+		report.push_str(&format!("\nEntries by Level:\n"));
+		for (i, &count) in self.stats.entries_by_level.iter().enumerate() {
+			if count > 0 {
+				let level = match i {
+					0 => LogLevel::Emergency,
+					1 => LogLevel::Alert,
+					2 => LogLevel::Critical,
+					3 => LogLevel::Error,
+					4 => LogLevel::Warning,
+					5 => LogLevel::Notice,
+					6 => LogLevel::Info,
+					7 => LogLevel::Debug,
+					_ => continue,
+				};
+				report.push_str(&format!("  {:?}: {}\n", level, count));
+			}
+		}
+
+		if !self.entries.is_empty() {
+			report.push_str(&format!(
+				"\nRecent Entries ({}):\n",
+				core::cmp::min(10, self.entries.len())
+			));
+			for entry in self.entries.iter().rev().take(10) {
+				report.push_str(&format!("  {}\n", entry.format(false).trim()));
+			}
+		}
+
+		report
+	}
+}
+
+/// Global kernel logger
+static KERNEL_LOGGER: Spinlock<Option<KernelLogger>> = Spinlock::new(None);
+
+/// Initialize kernel logging system
+pub fn init_logging() -> Result<()> {
+	let mut logger = KERNEL_LOGGER.lock();
+	*logger = Some(KernelLogger::new());
+
+	if let Some(ref mut l) = *logger {
+		let config = LoggerConfig::new()
+			.with_level(LogLevel::Info)
+			.with_max_entries(2000);
+		l.init(config);
+	}
+
+	// Log initialization message
+	log_info("logging", "Kernel logging system initialized");
+	Ok(())
+}
+
+/// Main logging function
+pub fn log(level: LogLevel, module: &str, message: &str) {
+	let mut logger = KERNEL_LOGGER.lock();
+	if let Some(ref mut l) = *logger {
+		l.log(level, module, message);
+	}
+}
+
+/// Convenience logging functions
+pub fn log_emergency(module: &str, message: &str) {
+	log(LogLevel::Emergency, module, message);
+}
+
+pub fn log_alert(module: &str, message: &str) {
+	log(LogLevel::Alert, module, message);
+}
+
+pub fn log_critical(module: &str, message: &str) {
+	log(LogLevel::Critical, module, message);
+}
+
+pub fn log_error(module: &str, message: &str) {
+	log(LogLevel::Error, module, message);
+}
+
+pub fn log_warning(module: &str, message: &str) {
+	log(LogLevel::Warning, module, message);
+}
+
+pub fn log_notice(module: &str, message: &str) {
+	log(LogLevel::Notice, module, message);
+}
+
+pub fn log_info(module: &str, message: &str) {
+	log(LogLevel::Info, module, message);
+}
+
+pub fn log_debug(module: &str, message: &str) {
+	log(LogLevel::Debug, module, message);
+}
+
+/// Get logging statistics
+pub fn get_log_stats() -> Option<LogStats> {
+	let logger = KERNEL_LOGGER.lock();
+	if let Some(ref l) = *logger {
+		Some(LogStats {
+			total_entries: l.stats.total_entries,
+			entries_by_level: l.stats.entries_by_level,
+			dropped_entries: l.stats.dropped_entries,
+		})
+	} else {
+		None
+	}
+}
+
+/// Generate logging report
+pub fn generate_log_report() -> String {
+	let logger = KERNEL_LOGGER.lock();
+	if let Some(ref l) = *logger {
+		l.generate_report()
+	} else {
+		"Logging system not initialized".into()
+	}
+}
+
+/// Dump log buffer
+pub fn dump_log_buffer() -> String {
+	let logger = KERNEL_LOGGER.lock();
+	if let Some(ref l) = *logger {
+		l.dump_buffer()
+	} else {
+		"Logging system not initialized".into()
+	}
+}
+
+/// Clear log buffer
+pub fn clear_log_buffer() {
+	let mut logger = KERNEL_LOGGER.lock();
+	if let Some(ref mut l) = *logger {
+		l.clear();
+	}
+}
+
+/// Set log level
+pub fn set_log_level(level: LogLevel) {
+	let mut logger = KERNEL_LOGGER.lock();
+	if let Some(ref mut l) = *logger {
+		l.set_level(level);
+	}
+}
+
+/// Debugging macros
+#[macro_export]
+macro_rules! debug_print {
+    ($category:expr, $($arg:tt)*) => {
+        crate::logging::log_debug(stringify!($category), &alloc::format!($($arg)*));
+    };
+}
+
+#[macro_export]
+macro_rules! trace_function {
+	($func:expr) => {
+		crate::logging::log_debug("trace", &alloc::format!("Entering function: {}", $func));
+	};
+}
+
+/// Kernel assertions with logging
+#[macro_export]
+macro_rules! kernel_assert {
+	($cond:expr) => {
+		if !$cond {
+			crate::logging::log_critical(
+				"assert",
+				&alloc::format!(
+					"Assertion failed: {} at {}:{}",
+					stringify!($cond),
+					file!(),
+					line!()
+				),
+			);
+			panic!("Kernel assertion failed: {}", stringify!($cond));
+		}
+	};
+	($cond:expr, $msg:expr) => {
+		if !$cond {
+			crate::logging::log_critical(
+				"assert",
+				&alloc::format!(
+					"Assertion failed: {} - {} at {}:{}",
+					stringify!($cond),
+					$msg,
+					file!(),
+					line!()
+				),
+			);
+			panic!("Kernel assertion failed: {} - {}", stringify!($cond), $msg);
+		}
+	};
+}
+
+/// Memory debugging helpers
+pub mod debug {
+	use super::*;
+
+	pub fn dump_memory(addr: usize, size: usize, label: &str) {
+		let mut output = format!(
+			"Memory dump: {} (addr: 0x{:x}, size: {})\n",
+			label, addr, size
+		);
+
+		unsafe {
+			let ptr = addr as *const u8;
+			for i in 0..core::cmp::min(size, 256) {
+				if i % 16 == 0 {
+					output.push_str(&format!("\n{:08x}: ", addr + i));
+				}
+				output.push_str(&format!("{:02x} ", *ptr.add(i)));
+			}
+		}
+
+		log_debug("memory", &output);
+	}
+
+	pub fn log_stack_trace() {
+		// TODO: Implement proper stack unwinding
+		log_debug("stack", "Stack trace not yet implemented");
+	}
+
+	pub fn check_kernel_stack() {
+		// TODO: Check if kernel stack is getting low
+		log_debug("stack", "Kernel stack check not yet implemented");
+	}
+}

kernel/src/main.rs

@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel main entry point
+
+#![no_std]
+#![no_main]
+
+extern crate kernel;
+
+use core::arch::global_asm;
+
+// Include boot assembly
+#[cfg(target_arch = "x86_64")]
+global_asm!(include_str!("arch/x86_64/boot.s"), options(att_syntax));
+
+/// Entry point called by boot.s assembly code
+/// This is just a wrapper to ensure the kernel crate is linked
+#[no_mangle]
+pub extern "C" fn rust_main() -> ! {
+	// This function shouldn't be called directly if boot.s calls kernel_main_multiboot
+	// But if it is called, we redirect to the kernel library
+	loop {
+		unsafe {
+			core::arch::asm!("hlt");
+		}
+	}
+}
+
+// Panic handler is defined in the kernel library

kernel/src/memfs.rs

@@ -0,0 +1,501 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Simple in-memory file system
+
+use alloc::{
+	boxed::Box,
+	collections::BTreeMap,
+	string::{String, ToString},
+	vec,
+	vec::Vec,
+};
+
+use crate::error::Result;
+use crate::sync::Spinlock;
+use crate::{error, info, warn};
+
+/// File type
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum FileType {
+	RegularFile,
+	Directory,
+	SymbolicLink,
+	CharDevice,
+	BlockDevice,
+}
+
+/// File permissions (simplified)
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct FileMode(pub u32);
+
+impl FileMode {
+	pub const READ: u32 = 0o444;
+	pub const WRITE: u32 = 0o222;
+	pub const EXECUTE: u32 = 0o111;
+	pub const ALL: u32 = 0o777;
+
+	pub fn new(mode: u32) -> Self {
+		Self(mode)
+	}
+
+	pub fn can_read(&self) -> bool {
+		self.0 & Self::READ != 0
+	}
+
+	pub fn can_write(&self) -> bool {
+		self.0 & Self::WRITE != 0
+	}
+
+	pub fn can_execute(&self) -> bool {
+		self.0 & Self::EXECUTE != 0
+	}
+}
+
+/// In-memory file node
+#[derive(Debug)]
+pub struct MemFile {
+	pub name: String,
+	pub file_type: FileType,
+	pub mode: FileMode,
+	pub size: usize,
+	pub data: Vec<u8>,
+	pub children: BTreeMap<String, Box<MemFile>>,
+	pub parent: Option<String>,
+}
+
+impl MemFile {
+	pub fn new_file(name: String, mode: FileMode) -> Self {
+		Self {
+			name,
+			file_type: FileType::RegularFile,
+			mode,
+			size: 0,
+			data: Vec::new(),
+			children: BTreeMap::new(),
+			parent: None,
+		}
+	}
+
+	pub fn new_dir(name: String, mode: FileMode) -> Self {
+		Self {
+			name,
+			file_type: FileType::Directory,
+			mode,
+			size: 0,
+			data: Vec::new(),
+			children: BTreeMap::new(),
+			parent: None,
+		}
+	}
+
+	pub fn is_dir(&self) -> bool {
+		self.file_type == FileType::Directory
+	}
+
+	pub fn is_file(&self) -> bool {
+		self.file_type == FileType::RegularFile
+	}
+
+	/// Write data to file
+	pub fn write(&mut self, data: &[u8]) -> Result<usize> {
+		if !self.mode.can_write() {
+			return Err(crate::error::Error::PermissionDenied);
+		}
+
+		if !self.is_file() {
+			return Err(crate::error::Error::InvalidOperation);
+		}
+
+		self.data.extend_from_slice(data);
+		self.size = self.data.len();
+		Ok(data.len())
+	}
+
+	/// Read data from file
+	pub fn read(&self, offset: usize, buffer: &mut [u8]) -> Result<usize> {
+		if !self.mode.can_read() {
+			return Err(crate::error::Error::PermissionDenied);
+		}
+
+		if !self.is_file() {
+			return Err(crate::error::Error::InvalidOperation);
+		}
+
+		if offset >= self.data.len() {
+			return Ok(0);
+		}
+
+		let available = self.data.len() - offset;
+		let to_read = buffer.len().min(available);
+
+		buffer[..to_read].copy_from_slice(&self.data[offset..offset + to_read]);
+		Ok(to_read)
+	}
+
+	/// Add child to directory
+	pub fn add_child(&mut self, child: MemFile) -> Result<()> {
+		if !self.is_dir() {
+			return Err(crate::error::Error::InvalidOperation);
+		}
+
+		let name = child.name.clone();
+		self.children.insert(name, Box::new(child));
+		Ok(())
+	}
+
+	/// Remove child from directory
+	pub fn remove_child(&mut self, name: &str) -> Result<()> {
+		if !self.is_dir() {
+			return Err(crate::error::Error::InvalidOperation);
+		}
+
+		if self.children.remove(name).is_some() {
+			Ok(())
+		} else {
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	/// Get child by name
+	pub fn get_child(&self, name: &str) -> Option<&MemFile> {
+		self.children.get(name).map(|f| f.as_ref())
+	}
+
+	/// Get child by name (mutable)
+	pub fn get_child_mut(&mut self, name: &str) -> Option<&mut MemFile> {
+		self.children.get_mut(name).map(|f| f.as_mut())
+	}
+
+	/// List directory contents
+	pub fn list_children(&self) -> Vec<&str> {
+		if !self.is_dir() {
+			return Vec::new();
+		}
+
+		self.children.keys().map(|s| s.as_str()).collect()
+	}
+}
+
+/// Simple in-memory file system
+pub struct MemFileSystem {
+	root: MemFile,
+	current_dir: String,
+}
+
+impl MemFileSystem {
+	pub fn new() -> Self {
+		let root = MemFile::new_dir("/".to_string(), FileMode::new(FileMode::ALL));
+
+		Self {
+			root,
+			current_dir: "/".to_string(),
+		}
+	}
+
+	/// Initialize with some default files
+	pub fn init_default_files(&mut self) -> Result<()> {
+		// Create /proc directory
+		let proc_dir = MemFile::new_dir(
+			"proc".to_string(),
+			FileMode::new(FileMode::READ | FileMode::EXECUTE),
+		);
+		self.root.add_child(proc_dir)?;
+
+		// Create /tmp directory
+		let tmp_dir = MemFile::new_dir("tmp".to_string(), FileMode::new(FileMode::ALL));
+		self.root.add_child(tmp_dir)?;
+
+		// Create /dev directory
+		let dev_dir = MemFile::new_dir("dev".to_string(), FileMode::new(FileMode::ALL));
+		self.root.add_child(dev_dir)?;
+
+		// Create some example files
+		let mut readme =
+			MemFile::new_file("README.txt".to_string(), FileMode::new(FileMode::READ));
+		readme.write(
+			b"Welcome to the Rust Kernel!\nThis is a simple in-memory file system.\n",
+		)?;
+		self.root.add_child(readme)?;
+
+		let mut version =
+			MemFile::new_file("version".to_string(), FileMode::new(FileMode::READ));
+		version.write(crate::VERSION.as_bytes())?;
+		self.root.add_child(version)?;
+
+		info!("Default file system structure created");
+		Ok(())
+	}
+
+	/// Resolve path to file
+	fn resolve_path(&self, path: &str) -> Option<&MemFile> {
+		if path == "/" {
+			return Some(&self.root);
+		}
+
+		let parts: Vec<&str> = path.trim_start_matches('/').split('/').collect();
+		let mut current = &self.root;
+
+		for part in parts {
+			if part.is_empty() {
+				continue;
+			}
+			current = current.get_child(part)?;
+		}
+
+		Some(current)
+	}
+
+	/// Resolve path to file (mutable)
+	fn resolve_path_mut(&mut self, path: &str) -> Option<&mut MemFile> {
+		if path == "/" {
+			return Some(&mut self.root);
+		}
+
+		let parts: Vec<&str> = path.trim_start_matches('/').split('/').collect();
+		let mut current = &mut self.root;
+
+		for part in parts {
+			if part.is_empty() {
+				continue;
+			}
+			current = current.get_child_mut(part)?;
+		}
+
+		Some(current)
+	}
+
+	/// Create a file
+	pub fn create_file(&mut self, path: &str, mode: FileMode) -> Result<()> {
+		let (dir_path, filename) = self.split_path(path);
+
+		if let Some(dir) = self.resolve_path_mut(&dir_path) {
+			if !dir.is_dir() {
+				return Err(crate::error::Error::InvalidOperation);
+			}
+
+			let file = MemFile::new_file(filename, mode);
+			dir.add_child(file)?;
+			Ok(())
+		} else {
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	/// Create a directory
+	pub fn create_dir(&mut self, path: &str, mode: FileMode) -> Result<()> {
+		let (dir_path, dirname) = self.split_path(path);
+
+		if let Some(dir) = self.resolve_path_mut(&dir_path) {
+			if !dir.is_dir() {
+				return Err(crate::error::Error::InvalidOperation);
+			}
+
+			let new_dir = MemFile::new_dir(dirname, mode);
+			dir.add_child(new_dir)?;
+			Ok(())
+		} else {
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	/// Write to a file
+	pub fn write_file(&mut self, path: &str, data: &[u8]) -> Result<usize> {
+		if let Some(file) = self.resolve_path_mut(path) {
+			file.write(data)
+		} else {
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	/// Read from a file
+	pub fn read_file(&self, path: &str, offset: usize, buffer: &mut [u8]) -> Result<usize> {
+		if let Some(file) = self.resolve_path(path) {
+			file.read(offset, buffer)
+		} else {
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	/// List directory contents
+	pub fn list_dir(&self, path: &str) -> Result<Vec<(String, FileType, usize)>> {
+		if let Some(dir) = self.resolve_path(path) {
+			if !dir.is_dir() {
+				return Err(crate::error::Error::InvalidOperation);
+			}
+
+			let mut entries = Vec::new();
+			for (name, child) in &dir.children {
+				entries.push((name.clone(), child.file_type, child.size));
+			}
+			Ok(entries)
+		} else {
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	/// Remove a file or directory
+	pub fn remove(&mut self, path: &str) -> Result<()> {
+		let (dir_path, filename) = self.split_path(path);
+
+		if let Some(dir) = self.resolve_path_mut(&dir_path) {
+			dir.remove_child(&filename)
+		} else {
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	/// Get file info
+	pub fn stat(&self, path: &str) -> Result<(FileType, FileMode, usize)> {
+		if let Some(file) = self.resolve_path(path) {
+			Ok((file.file_type, file.mode, file.size))
+		} else {
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	/// Split path into directory and filename
+	fn split_path(&self, path: &str) -> (String, String) {
+		if let Some(pos) = path.rfind('/') {
+			let dir = if pos == 0 { "/" } else { &path[..pos] };
+			let file = &path[pos + 1..];
+			(dir.to_string(), file.to_string())
+		} else {
+			("/".to_string(), path.to_string())
+		}
+	}
+}
+
+/// Global file system instance
+static FILESYSTEM: Spinlock<Option<MemFileSystem>> = Spinlock::new(None);
+
+/// Initialize the in-memory file system
+pub fn init_memfs() -> Result<()> {
+	info!("Initializing in-memory file system");
+
+	let mut fs = MemFileSystem::new();
+	fs.init_default_files()?;
+
+	let mut filesystem = FILESYSTEM.lock();
+	*filesystem = Some(fs);
+
+	info!("In-memory file system initialized");
+	Ok(())
+}
+
+/// File system operations for shell
+pub fn fs_list(path: &str) -> Result<Vec<(String, FileType, usize)>> {
+	let filesystem = FILESYSTEM.lock();
+	if let Some(ref fs) = *filesystem {
+		fs.list_dir(path)
+	} else {
+		Err(crate::error::Error::NotInitialized)
+	}
+}
+
+pub fn fs_read(path: &str) -> Result<Vec<u8>> {
+	let filesystem = FILESYSTEM.lock();
+	if let Some(ref fs) = *filesystem {
+		let mut buffer = vec![0u8; 4096]; // Read up to 4KB
+		let bytes_read = fs.read_file(path, 0, &mut buffer)?;
+		buffer.truncate(bytes_read);
+		Ok(buffer)
+	} else {
+		Err(crate::error::Error::NotInitialized)
+	}
+}
+
+pub fn fs_write(path: &str, data: &[u8]) -> Result<usize> {
+	let mut filesystem = FILESYSTEM.lock();
+	if let Some(ref mut fs) = *filesystem {
+		fs.write_file(path, data)
+	} else {
+		Err(crate::error::Error::NotInitialized)
+	}
+}
+
+pub fn fs_create_file(path: &str) -> Result<()> {
+	let mut filesystem = FILESYSTEM.lock();
+	if let Some(ref mut fs) = *filesystem {
+		fs.create_file(path, FileMode::new(FileMode::READ | FileMode::WRITE))
+	} else {
+		Err(crate::error::Error::NotInitialized)
+	}
+}
+
+pub fn fs_create_dir(path: &str) -> Result<()> {
+	let mut filesystem = FILESYSTEM.lock();
+	if let Some(ref mut fs) = *filesystem {
+		fs.create_dir(path, FileMode::new(FileMode::ALL))
+	} else {
+		Err(crate::error::Error::NotInitialized)
+	}
+}
+
+pub fn fs_remove(path: &str) -> Result<()> {
+	let mut filesystem = FILESYSTEM.lock();
+	if let Some(ref mut fs) = *filesystem {
+		fs.remove(path)
+	} else {
+		Err(crate::error::Error::NotInitialized)
+	}
+}
+
+pub fn fs_stat(path: &str) -> Result<(FileType, FileMode, usize)> {
+	let filesystem = FILESYSTEM.lock();
+	if let Some(ref fs) = *filesystem {
+		fs.stat(path)
+	} else {
+		Err(crate::error::Error::NotInitialized)
+	}
+}
+
+/// File system statistics for diagnostics
+#[derive(Debug, Clone)]
+pub struct FileSystemStats {
+	pub files_count: usize,
+	pub directories_count: usize,
+	pub total_size: usize,
+}
+
+/// Get file system statistics for diagnostics
+pub fn get_filesystem_stats() -> Result<FileSystemStats> {
+	let filesystem = FILESYSTEM.lock();
+	if let Some(ref fs) = *filesystem {
+		let mut files_count = 0;
+		let mut directories_count = 0;
+		let mut total_size = 0;
+
+		// Count files recursively (simplified implementation)
+		fn count_files(
+			file: &MemFile,
+			files: &mut usize,
+			dirs: &mut usize,
+			size: &mut usize,
+		) {
+			if file.is_dir() {
+				*dirs += 1;
+				for child in file.children.values() {
+					count_files(child, files, dirs, size);
+				}
+			} else {
+				*files += 1;
+				*size += file.data.len();
+			}
+		}
+
+		count_files(
+			&fs.root,
+			&mut files_count,
+			&mut directories_count,
+			&mut total_size,
+		);
+
+		Ok(FileSystemStats {
+			files_count,
+			directories_count,
+			total_size,
+		})
+	} else {
+		Err(crate::error::Error::NotInitialized)
+	}
+}

kernel/src/memory/advanced_allocator.rs

@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Advanced memory allocator with debugging and tracking capabilities
+
+use alloc::{collections::BTreeMap, vec::Vec};
+use core::alloc::{GlobalAlloc, Layout};
+use core::ptr::NonNull;
+use core::sync::atomic::{AtomicU64, AtomicUsize, Ordering};
+
+use crate::error::{Error, Result};
+use crate::sync::Spinlock;
+
+/// Allocation tracking information
+#[derive(Debug, Clone)]
+pub struct AllocationInfo {
+	pub size: usize,
+	pub layout: Layout,
+	pub timestamp: u64,
+	pub caller: Option<usize>, // Return address for debugging
+}
+
+/// Memory allocation statistics
+#[derive(Debug, Default)]
+pub struct MemoryStats {
+	pub total_allocated: AtomicU64,
+	pub total_freed: AtomicU64,
+	pub current_allocated: AtomicU64,
+	pub allocation_count: AtomicU64,
+	pub free_count: AtomicU64,
+	pub peak_usage: AtomicU64,
+	pub fragmentation_events: AtomicU64,
+}
+
+/// Advanced allocator with tracking and debugging
+pub struct AdvancedAllocator {
+	base_allocator: linked_list_allocator::LockedHeap,
+	allocations: Spinlock<BTreeMap<usize, AllocationInfo>>,
+	stats: MemoryStats,
+	debug_mode: AtomicU64, // Bitfield for debug features
+}
+
+impl AdvancedAllocator {
+	/// Create new advanced allocator
+	pub const fn new() -> Self {
+		Self {
+			base_allocator: linked_list_allocator::LockedHeap::empty(),
+			allocations: Spinlock::new(BTreeMap::new()),
+			stats: MemoryStats {
+				total_allocated: AtomicU64::new(0),
+				total_freed: AtomicU64::new(0),
+				current_allocated: AtomicU64::new(0),
+				allocation_count: AtomicU64::new(0),
+				free_count: AtomicU64::new(0),
+				peak_usage: AtomicU64::new(0),
+				fragmentation_events: AtomicU64::new(0),
+			},
+			debug_mode: AtomicU64::new(0),
+		}
+	}
+
+	/// Initialize the allocator with heap memory
+	pub unsafe fn init(&self, heap_start: usize, heap_size: usize) {
+		self.base_allocator
+			.lock()
+			.init(heap_start as *mut u8, heap_size);
+	}
+
+	/// Enable debug mode features
+	pub fn set_debug_mode(&self, mode: u64) {
+		self.debug_mode.store(mode, Ordering::Relaxed);
+	}
+
+	/// Get current memory statistics
+	pub fn get_stats(&self) -> MemoryStatsSnapshot {
+		MemoryStatsSnapshot {
+			total_allocated: self.stats.total_allocated.load(Ordering::Relaxed),
+			total_freed: self.stats.total_freed.load(Ordering::Relaxed),
+			current_allocated: self.stats.current_allocated.load(Ordering::Relaxed),
+			allocation_count: self.stats.allocation_count.load(Ordering::Relaxed),
+			free_count: self.stats.free_count.load(Ordering::Relaxed),
+			peak_usage: self.stats.peak_usage.load(Ordering::Relaxed),
+			fragmentation_events: self
+				.stats
+				.fragmentation_events
+				.load(Ordering::Relaxed),
+			active_allocations: self.allocations.lock().len(),
+		}
+	}
+
+	/// Get detailed allocation information
+	pub fn get_allocations(&self) -> Vec<(usize, AllocationInfo)> {
+		self.allocations
+			.lock()
+			.iter()
+			.map(|(&addr, info)| (addr, info.clone()))
+			.collect()
+	}
+
+	/// Check for memory leaks
+	pub fn check_leaks(&self) -> Vec<(usize, AllocationInfo)> {
+		let current_time = crate::time::get_jiffies();
+		self.allocations
+			.lock()
+			.iter()
+			.filter(|(_, info)| {
+				current_time.0 > info.timestamp
+					&& current_time.0 - info.timestamp > 10000
+			}) // Old allocations
+			.map(|(&addr, info)| (addr, info.clone()))
+			.collect()
+	}
+
+	/// Defragment memory (placeholder for future implementation)
+	pub fn defragment(&self) -> Result<usize> {
+		// This would implement memory compaction
+		// For now, just return that no bytes were moved
+		Ok(0)
+	}
+}
+
+unsafe impl GlobalAlloc for AdvancedAllocator {
+	unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
+		let ptr = self.base_allocator.alloc(layout);
+
+		if !ptr.is_null() {
+			// Update statistics
+			let size = layout.size() as u64;
+			self.stats
+				.total_allocated
+				.fetch_add(size, Ordering::Relaxed);
+			self.stats.allocation_count.fetch_add(1, Ordering::Relaxed);
+			let current =
+				self.stats
+					.current_allocated
+					.fetch_add(size, Ordering::Relaxed) + size;
+
+			// Update peak usage
+			let mut peak = self.stats.peak_usage.load(Ordering::Relaxed);
+			while current > peak {
+				match self.stats.peak_usage.compare_exchange_weak(
+					peak,
+					current,
+					Ordering::Relaxed,
+					Ordering::Relaxed,
+				) {
+					Ok(_) => break,
+					Err(x) => peak = x,
+				}
+			}
+
+			// Track allocation if debug mode is enabled
+			if self.debug_mode.load(Ordering::Relaxed) & 1 != 0 {
+				let info = AllocationInfo {
+					size: layout.size(),
+					layout,
+					timestamp: crate::time::get_jiffies().0,
+					caller: None, // TODO: Get return address
+				};
+				self.allocations.lock().insert(ptr as usize, info);
+			}
+		}
+
+		ptr
+	}
+
+	unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
+		self.base_allocator.dealloc(ptr, layout);
+
+		if !ptr.is_null() {
+			// Update statistics
+			let size = layout.size() as u64;
+			self.stats.total_freed.fetch_add(size, Ordering::Relaxed);
+			self.stats.free_count.fetch_add(1, Ordering::Relaxed);
+			self.stats
+				.current_allocated
+				.fetch_sub(size, Ordering::Relaxed);
+
+			// Remove allocation tracking
+			if self.debug_mode.load(Ordering::Relaxed) & 1 != 0 {
+				self.allocations.lock().remove(&(ptr as usize));
+			}
+		}
+	}
+}
+
+/// Snapshot of memory statistics
+#[derive(Debug, Clone)]
+pub struct MemoryStatsSnapshot {
+	pub total_allocated: u64,
+	pub total_freed: u64,
+	pub current_allocated: u64,
+	pub allocation_count: u64,
+	pub free_count: u64,
+	pub peak_usage: u64,
+	pub fragmentation_events: u64,
+	pub active_allocations: usize,
+}
+
+/// Debug mode flags
+pub mod debug_flags {
+	pub const TRACK_ALLOCATIONS: u64 = 1 << 0;
+	pub const DETECT_LEAKS: u64 = 1 << 1;
+	pub const POISON_MEMORY: u64 = 1 << 2;
+	pub const GUARD_PAGES: u64 = 1 << 3;
+}
+
+/// Global advanced allocator instance
+#[global_allocator]
+pub static ALLOCATOR: AdvancedAllocator = AdvancedAllocator::new();
+
+/// Initialize the advanced allocator
+pub unsafe fn init_advanced_allocator(heap_start: usize, heap_size: usize) {
+	ALLOCATOR.init(heap_start, heap_size);
+	ALLOCATOR.set_debug_mode(debug_flags::TRACK_ALLOCATIONS | debug_flags::DETECT_LEAKS);
+	crate::info!("Advanced allocator initialized with {} bytes", heap_size);
+}
+
+/// Get global memory statistics
+pub fn get_memory_stats() -> MemoryStatsSnapshot {
+	ALLOCATOR.get_stats()
+}
+
+/// Get current allocations for debugging
+pub fn get_current_allocations() -> Vec<(usize, AllocationInfo)> {
+	ALLOCATOR.get_allocations()
+}
+
+/// Check for memory leaks
+pub fn check_memory_leaks() -> Vec<(usize, AllocationInfo)> {
+	ALLOCATOR.check_leaks()
+}
+
+/// Trigger memory defragmentation
+pub fn defragment_memory() -> Result<usize> {
+	ALLOCATOR.defragment()
+}

kernel/src/memory/allocator.rs

@@ -0,0 +1,222 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Memory allocator implementation - Enhanced with buddy allocator
+
+use alloc::vec::Vec;
+
+use crate::error::{Error, Result};
+use crate::memory::advanced_allocator::ALLOCATOR;
+use crate::sync::Spinlock;
+use crate::types::{PhysAddr, VirtAddr, PAGE_SIZE};
+
+/// Maximum order for buddy allocator (2^MAX_ORDER pages)
+const MAX_ORDER: usize = 11;
+
+/// Page frame number
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct PageFrameNumber(pub usize);
+
+impl PageFrameNumber {
+	pub fn to_phys_addr(self) -> PhysAddr {
+		PhysAddr::new(self.0 * PAGE_SIZE)
+	}
+
+	pub fn from_phys_addr(addr: PhysAddr) -> Self {
+		Self(addr.as_usize() / PAGE_SIZE)
+	}
+}
+
+/// Page allocation flags
+#[derive(Debug, Clone, Copy)]
+pub struct GfpFlags(pub u32);
+
+impl GfpFlags {
+	pub const KERNEL: Self = Self(0x01);
+	pub const USER: Self = Self(0x02);
+	pub const ATOMIC: Self = Self(0x04);
+	pub const ZERO: Self = Self(0x08);
+	pub const DMA: Self = Self(0x10);
+	pub const HIGHMEM: Self = Self(0x20);
+}
+
+/// Free page block in buddy allocator
+#[derive(Debug)]
+struct FreeBlock {
+	pfn: PageFrameNumber,
+	#[allow(dead_code)]
+	order: usize,
+}
+
+/// Simple buddy allocator for page allocation
+pub struct BuddyAllocator {
+	/// Free lists for each order
+	free_lists: [Vec<FreeBlock>; MAX_ORDER],
+	/// Total number of pages
+	total_pages: usize,
+	/// Base physical address
+	#[allow(dead_code)]
+	base_addr: PhysAddr,
+}
+
+impl BuddyAllocator {
+	pub fn new(base_addr: PhysAddr, total_pages: usize) -> Self {
+		const EMPTY_VEC: Vec<FreeBlock> = Vec::new();
+
+		Self {
+			free_lists: [EMPTY_VEC; MAX_ORDER],
+			total_pages,
+			base_addr,
+		}
+	}
+
+	/// Add a free memory region to the allocator
+	pub fn add_free_region(&mut self, start_pfn: PageFrameNumber, num_pages: usize) {
+		// Simple implementation: add as single-page blocks
+		for i in 0..num_pages {
+			self.free_lists[0].push(FreeBlock {
+				pfn: PageFrameNumber(start_pfn.0 + i),
+				order: 0,
+			});
+		}
+	}
+
+	/// Allocate pages of given order
+	pub fn alloc_pages(&mut self, order: usize) -> Result<PageFrameNumber> {
+		if order >= MAX_ORDER {
+			return Err(Error::InvalidArgument);
+		}
+
+		// Try to find a free block of the requested order
+		if let Some(block) = self.free_lists[order].pop() {
+			return Ok(block.pfn);
+		}
+
+		// For simplicity, just allocate from order 0 if we need higher orders
+		if order > 0 {
+			// Try to get multiple single pages (simplified approach)
+			let pages_needed = 1 << order;
+			if self.free_lists[0].len() >= pages_needed {
+				let first_pfn = self.free_lists[0].pop().unwrap().pfn;
+				// Remove additional pages
+				for _ in 1..pages_needed {
+					if self.free_lists[0].is_empty() {
+						// Put back the first page if we can't get enough
+						self.free_lists[0].push(FreeBlock {
+							pfn: first_pfn,
+							order: 0,
+						});
+						return Err(Error::OutOfMemory);
+					}
+					self.free_lists[0].pop();
+				}
+				return Ok(first_pfn);
+			}
+		}
+
+		Err(Error::OutOfMemory)
+	}
+
+	/// Free pages
+	pub fn free_pages(&mut self, pfn: PageFrameNumber, order: usize) {
+		if order >= MAX_ORDER {
+			return;
+		}
+
+		// Simple implementation: add back to the appropriate order
+		let pages_to_free = 1 << order;
+		for i in 0..pages_to_free {
+			self.free_lists[0].push(FreeBlock {
+				pfn: PageFrameNumber(pfn.0 + i),
+				order: 0,
+			});
+		}
+	}
+
+	/// Get free page count
+	pub fn free_pages_count(&self) -> usize {
+		let mut count = 0;
+		for order in 0..MAX_ORDER {
+			count += self.free_lists[order].len() * (1 << order);
+		}
+		count
+	}
+}
+
+/// Global buddy allocator for page allocation
+static PAGE_ALLOCATOR: Spinlock<Option<BuddyAllocator>> = Spinlock::new(None);
+
+/// Heap start address (will be set during initialization)
+static mut HEAP_START: usize = 0;
+static mut HEAP_SIZE: usize = 0;
+
+/// Initialize the allocators
+pub fn init() -> Result<()> {
+	// Initialize heap allocator
+	let heap_start = 0x_4444_4444_0000;
+	let heap_size = 100 * 1024; // 100 KB
+
+	unsafe {
+		HEAP_START = heap_start;
+		HEAP_SIZE = heap_size;
+		crate::memory::advanced_allocator::init_advanced_allocator(heap_start, heap_size);
+	}
+
+	// Initialize page allocator
+	// For demo purposes, assume we have 1024 pages starting at 1MB
+	let page_base = PhysAddr::new(0x100000); // 1MB
+	let total_pages = 1024;
+
+	let mut buddy = BuddyAllocator::new(page_base, total_pages);
+	buddy.add_free_region(
+		PageFrameNumber(page_base.as_usize() / PAGE_SIZE),
+		total_pages,
+	);
+
+	*PAGE_ALLOCATOR.lock() = Some(buddy);
+
+	Ok(())
+}
+
+/// Get heap statistics
+pub fn heap_stats() -> (usize, usize) {
+	unsafe { (HEAP_START, HEAP_SIZE) }
+}
+
+/// Linux-compatible page allocation functions
+pub fn alloc_pages(order: usize, flags: GfpFlags) -> Result<PageFrameNumber> {
+	let mut allocator = PAGE_ALLOCATOR.lock();
+	if let Some(ref mut alloc) = *allocator {
+		alloc.alloc_pages(order)
+	} else {
+		Err(Error::NotInitialized)
+	}
+}
+
+pub fn free_pages(pfn: PageFrameNumber, order: usize) {
+	let mut allocator = PAGE_ALLOCATOR.lock();
+	if let Some(ref mut alloc) = *allocator {
+		alloc.free_pages(pfn, order);
+	}
+}
+
+/// Allocate a single page
+pub fn get_free_page(flags: GfpFlags) -> Result<VirtAddr> {
+	let pfn = alloc_pages(0, flags)?;
+	Ok(VirtAddr::new(pfn.to_phys_addr().as_usize()))
+}
+
+/// Free a single page
+pub fn free_page(addr: VirtAddr) {
+	let pfn = PageFrameNumber::from_phys_addr(PhysAddr::new(addr.as_usize()));
+	free_pages(pfn, 0);
+}
+
+/// Get page allocator statistics
+pub fn page_alloc_stats() -> Option<(usize, usize)> {
+	let allocator = PAGE_ALLOCATOR.lock();
+	if let Some(ref alloc) = *allocator {
+		Some((alloc.total_pages, alloc.free_pages_count()))
+	} else {
+		None
+	}
+}

kernel/src/memory/kmalloc.rs

@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel memory allocation (kmalloc)
+
+use alloc::collections::BTreeMap;
+use alloc::vec::Vec;
+use core::ptr::NonNull;
+
+use crate::error::{Error, Result};
+use crate::memory::allocator::{alloc_pages, free_pages, GfpFlags, PageFrameNumber};
+use crate::sync::Spinlock;
+
+/// Kmalloc size classes (powers of 2)
+const KMALLOC_SIZES: &[usize] = &[8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096];
+const MAX_KMALLOC_SIZE: usize = 4096;
+
+/// Slab allocator for small kernel allocations
+/// Uses physical addresses directly - they're identity-mapped in the first 1GB
+struct SlabAllocator {
+	size_classes: BTreeMap<usize, Vec<usize>>, // Store physical addresses
+	allocated_blocks: BTreeMap<usize, usize>,  // Maps physical addresses to size classes
+}
+
+impl SlabAllocator {
+	const fn new() -> Self {
+		Self {
+			size_classes: BTreeMap::new(),
+			allocated_blocks: BTreeMap::new(),
+		}
+	}
+
+	fn allocate(&mut self, size: usize) -> Result<*mut u8> {
+		// Find appropriate size class
+		let size_class = KMALLOC_SIZES
+			.iter()
+			.find(|&&s| s >= size)
+			.copied()
+			.unwrap_or(MAX_KMALLOC_SIZE);
+
+		if size_class > MAX_KMALLOC_SIZE {
+			return Err(Error::OutOfMemory);
+		}
+
+		// Try to get from free list
+		if let Some(free_list) = self.size_classes.get_mut(&size_class) {
+			if let Some(addr) = free_list.pop() {
+				self.allocated_blocks.insert(addr, size_class);
+				return Ok(addr as *mut u8);
+			}
+		}
+
+		// Allocate new page and split it
+		self.allocate_new_slab(size_class)
+	}
+
+	fn allocate_new_slab(&mut self, size_class: usize) -> Result<*mut u8> {
+		// Allocate a page using buddy allocator
+		let pfn = alloc_pages(0, GfpFlags::KERNEL)?;
+		let page_addr = pfn.to_phys_addr().as_usize();
+
+		// Split page into blocks of size_class
+		let blocks_per_page = 4096 / size_class;
+		let free_list = self.size_classes.entry(size_class).or_insert_with(Vec::new);
+
+		for i in 1..blocks_per_page {
+			let block_addr = page_addr + (i * size_class);
+			free_list.push(block_addr);
+		}
+
+		// Return the first block
+		self.allocated_blocks.insert(page_addr, size_class);
+		Ok(page_addr as *mut u8)
+	}
+
+	fn deallocate(&mut self, ptr: *mut u8) -> Result<()> {
+		let addr = ptr as usize;
+		if let Some(size_class) = self.allocated_blocks.remove(&addr) {
+			let free_list =
+				self.size_classes.entry(size_class).or_insert_with(Vec::new);
+			free_list.push(addr);
+			Ok(())
+		} else {
+			Err(Error::InvalidArgument)
+		}
+	}
+
+	pub fn stats(&self) -> (usize, usize, usize) {
+		let mut allocated_count = 0;
+		let mut allocated_bytes = 0;
+		for (_, size_class) in &self.allocated_blocks {
+			allocated_count += 1;
+			allocated_bytes += size_class;
+		}
+
+		let mut free_count = 0;
+		for (_, free_list) in &self.size_classes {
+			free_count += free_list.len();
+		}
+
+		(allocated_count, allocated_bytes, free_count)
+	}
+}
+
+static SLAB_ALLOCATOR: Spinlock<SlabAllocator> = Spinlock::new(SlabAllocator::new());
+
+/// Get kmalloc statistics
+pub fn get_stats() -> (usize, usize, usize) {
+	let allocator = SLAB_ALLOCATOR.lock();
+	allocator.stats()
+}
+
+/// Allocate kernel memory
+pub fn kmalloc(size: usize) -> Result<*mut u8> {
+	// Increment performance counter
+	crate::perf::counters::inc_memory_allocs();
+
+	if size == 0 {
+		return Err(Error::InvalidArgument);
+	}
+
+	if size <= MAX_KMALLOC_SIZE {
+		// Use slab allocator for small allocations
+		let mut allocator = SLAB_ALLOCATOR.lock();
+		allocator.allocate(size)
+	} else {
+		// Use buddy allocator for large allocations
+		let pages_needed = (size + 4095) / 4096;
+		let order = pages_needed.next_power_of_two().trailing_zeros() as usize;
+		let pfn = alloc_pages(order, GfpFlags::KERNEL)?;
+		Ok(pfn.to_phys_addr().as_usize() as *mut u8)
+	}
+}
+
+/// Free kernel memory
+pub fn kfree(ptr: *mut u8) {
+	if ptr.is_null() {
+		return;
+	}
+
+	// Try slab allocator first
+	if let Ok(()) = SLAB_ALLOCATOR.lock().deallocate(ptr) {
+		return;
+	}
+
+	// Try buddy allocator for large allocations
+	// TODO: Keep track of large allocations to know how many pages to free
+	// For now, assume single page
+	if let Some(_page) = NonNull::new(ptr as *mut crate::memory::Page) {
+		let pfn =
+			PageFrameNumber::from_phys_addr(crate::types::PhysAddr::new(ptr as usize));
+		free_pages(pfn, 0);
+	}
+}
+
+/// Allocate zeroed kernel memory
+pub fn kzalloc(size: usize) -> Result<*mut u8> {
+	let ptr = kmalloc(size)?;
+	unsafe {
+		core::ptr::write_bytes(ptr, 0, size);
+	}
+	Ok(ptr)
+}
+
+/// Reallocate kernel memory
+pub fn krealloc(ptr: *mut u8, old_size: usize, new_size: usize) -> Result<*mut u8> {
+	if ptr.is_null() {
+		return kmalloc(new_size);
+	}
+
+	if new_size == 0 {
+		kfree(ptr);
+		return Ok(core::ptr::null_mut());
+	}
+
+	let new_ptr = kmalloc(new_size)?;
+	let copy_size = core::cmp::min(old_size, new_size);
+
+	unsafe {
+		core::ptr::copy_nonoverlapping(ptr, new_ptr, copy_size);
+	}
+
+	kfree(ptr);
+	Ok(new_ptr)
+}
+
+/// Initialize the slab allocator
+pub fn init() -> Result<()> {
+	// No initialization needed - we use physical addresses directly
+	Ok(())
+}

kernel/src/memory/mod.rs

@@ -0,0 +1,622 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Memory management subsystem
+
+pub mod advanced_allocator;
+pub mod allocator;
+pub mod kmalloc;
+pub mod page;
+pub mod page_table;
+pub mod vmalloc;
+
+// Re-export important types
+use alloc::string::String;
+
+use linked_list_allocator::LockedHeap;
+pub use page::Page;
+
+use crate::error::{Error, Result};
+pub use crate::types::{Pfn, PhysAddr, VirtAddr}; // Re-export from types
+
+/// GFP (Get Free Pages) flags - compatible with Linux kernel
+pub mod gfp {
+	pub const GFP_KERNEL: u32 = 0;
+	pub const GFP_ATOMIC: u32 = 1;
+	pub const GFP_USER: u32 = 2;
+	pub const GFP_HIGHUSER: u32 = 3;
+	pub const GFP_DMA: u32 = 4;
+	pub const GFP_DMA32: u32 = 8;
+	pub const GFP_NOWAIT: u32 = 16;
+	pub const GFP_NOIO: u32 = 32;
+	pub const GFP_NOFS: u32 = 64;
+	pub const GFP_ZERO: u32 = 128;
+}
+
+/// Global heap allocator (using advanced allocator)
+// #[global_allocator]
+// static ALLOCATOR: LockedHeap = LockedHeap::empty();
+
+/// Linux-compatible allocation flags
+#[derive(Clone, Copy, PartialEq)]
+pub struct AllocFlags(u32);
+
+impl AllocFlags {
+	pub const fn new(flags: u32) -> Self {
+		Self(flags)
+	}
+
+	pub fn as_raw(self) -> u32 {
+		self.0
+	}
+
+	pub fn contains(self, flags: AllocFlags) -> bool {
+		(self.0 & flags.0) == flags.0
+	}
+}
+
+/// GFP flags constants
+pub const GFP_KERNEL: AllocFlags = AllocFlags::new(gfp::GFP_KERNEL);
+pub const GFP_ATOMIC: AllocFlags = AllocFlags::new(gfp::GFP_ATOMIC);
+pub const GFP_USER: AllocFlags = AllocFlags::new(gfp::GFP_USER);
+
+/// Page mapping flags
+#[derive(Clone, Copy, PartialEq, Debug)]
+pub struct PageFlags(u64);
+
+impl PageFlags {
+	pub const PRESENT: PageFlags = PageFlags(1 << 0);
+	pub const WRITABLE: PageFlags = PageFlags(1 << 1);
+	pub const USER: PageFlags = PageFlags(1 << 2);
+	pub const EXECUTABLE: PageFlags = PageFlags(1 << 63); // NX bit inverted
+
+	pub const fn new(flags: u64) -> Self {
+		Self(flags)
+	}
+
+	pub fn as_raw(self) -> u64 {
+		self.0
+	}
+
+	pub fn contains(self, flags: PageFlags) -> bool {
+		(self.0 & flags.0) == flags.0
+	}
+}
+
+impl core::ops::BitOr for PageFlags {
+	type Output = Self;
+
+	fn bitor(self, rhs: Self) -> Self::Output {
+		PageFlags(self.0 | rhs.0)
+	}
+}
+
+/// Initialize the memory management subsystem with proper Linux-style
+/// initialization
+pub fn init() -> Result<()> {
+	allocator::init()?;
+	page::init()?;
+
+	// Initialize zone allocator
+	init_zones()?;
+
+	// Set up buddy allocator
+	init_buddy_allocator()?;
+
+	// Initialize slab allocator
+	init_slab_allocator()?;
+
+	crate::info!("Memory management initialized");
+	Ok(())
+}
+
+/// Initialize memory zones (DMA, Normal, High)
+fn init_zones() -> Result<()> {
+	// TODO: Set up memory zones based on architecture
+	Ok(())
+}
+
+/// Initialize buddy allocator for page allocation
+fn init_buddy_allocator() -> Result<()> {
+	// TODO: Set up buddy allocator
+	Ok(())
+}
+
+/// Initialize slab allocator for object caching
+fn init_slab_allocator() -> Result<()> {
+	// TODO: Set up SLAB/SLUB allocator
+	Ok(())
+}
+
+/// Physical memory information
+#[derive(Debug)]
+pub struct MemoryInfo {
+	pub total_pages: usize,
+	pub free_pages: usize,
+	pub used_pages: usize,
+	pub kernel_pages: usize,
+}
+
+/// Get current memory information
+pub fn memory_info() -> MemoryInfo {
+	MemoryInfo {
+		total_pages: 0, // TODO: implement
+		free_pages: 0,
+		used_pages: 0,
+		kernel_pages: 0,
+	}
+}
+
+/// Memory statistics for diagnostics
+#[derive(Debug, Clone)]
+pub struct MemoryStats {
+	pub total: usize,
+	pub used: usize,
+	pub free: usize,
+	pub usage_percent: usize,
+}
+
+/// Get memory statistics for diagnostics
+pub fn get_memory_stats() -> Result<MemoryStats> {
+	let info = memory_info();
+	let total = if info.total_pages > 0 {
+		info.total_pages * 4096
+	} else {
+		64 * 1024 * 1024
+	}; // Default 64MB
+	let used = info.used_pages * 4096;
+	let free = total - used;
+	let usage_percent = if total > 0 { (used * 100) / total } else { 0 };
+
+	Ok(MemoryStats {
+		total,
+		used,
+		free,
+		usage_percent,
+	})
+}
+
+/// Allocate a page of physical memory
+pub fn alloc_page() -> Result<PhysAddr> {
+	page::alloc_page()
+}
+
+/// Free a page of physical memory
+pub fn free_page(addr: PhysAddr) {
+	page::free_page(addr)
+}
+
+/// Allocate a page of physical memory
+pub fn allocate_page() -> Result<PhysAddr> {
+	page::allocate_page()
+}
+
+/// Map a virtual address to a physical address
+pub fn map_page(virt: VirtAddr, phys: PhysAddr, flags: PageFlags) -> Result<()> {
+	// TODO: implement page table mapping with flags
+	Ok(())
+}
+
+/// Map a virtual address to a physical address (simple version)
+pub fn map_page_simple(virt: VirtAddr, phys: PhysAddr) -> Result<()> {
+	// TODO: implement page table mapping
+	map_page(virt, phys, PageFlags::PRESENT | PageFlags::WRITABLE)
+}
+
+/// Unmap a virtual address
+pub fn unmap_page(virt: VirtAddr) -> Result<()> {
+	// TODO: implement page table unmapping
+	Ok(())
+}
+
+/// Convert virtual address to physical address
+pub fn virt_to_phys(virt: VirtAddr) -> Result<PhysAddr> {
+	// TODO: implement address translation
+	Ok(PhysAddr::new(virt.as_usize()))
+}
+
+/// Convert physical address to virtual address
+pub fn phys_to_virt(phys: PhysAddr) -> Result<VirtAddr> {
+	// TODO: implement address translation
+	Ok(VirtAddr::new(phys.as_usize()))
+}
+
+/// Page table entry
+#[derive(Debug, Clone, Copy)]
+pub struct PageTableEntry(pub u64);
+
+impl PageTableEntry {
+	pub const fn new() -> Self {
+		Self(0)
+	}
+
+	pub fn present(self) -> bool {
+		self.0 & 1 != 0
+	}
+
+	pub fn writable(self) -> bool {
+		self.0 & 2 != 0
+	}
+
+	pub fn user_accessible(self) -> bool {
+		self.0 & 4 != 0
+	}
+
+	pub fn frame(self) -> Pfn {
+		Pfn((self.0 >> 12) as usize)
+	}
+
+	pub fn set_present(&mut self, present: bool) {
+		if present {
+			self.0 |= 1;
+		} else {
+			self.0 &= !1;
+		}
+	}
+
+	pub fn set_writable(&mut self, writable: bool) {
+		if writable {
+			self.0 |= 2;
+		} else {
+			self.0 &= !2;
+		}
+	}
+
+	pub fn set_user_accessible(&mut self, user: bool) {
+		if user {
+			self.0 |= 4;
+		} else {
+			self.0 &= !4;
+		}
+	}
+
+	pub fn set_frame(&mut self, frame: Pfn) {
+		self.0 = (self.0 & 0xfff) | ((frame.0 as u64) << 12);
+	}
+}
+
+/// Page table
+#[repr(align(4096))]
+pub struct PageTable {
+	entries: [PageTableEntry; 512],
+}
+
+impl PageTable {
+	pub const fn new() -> Self {
+		Self {
+			entries: [PageTableEntry::new(); 512],
+		}
+	}
+
+	pub fn zero(&mut self) {
+		for entry in self.entries.iter_mut() {
+			*entry = PageTableEntry::new();
+		}
+	}
+}
+
+/// Memory mapping flags
+bitflags::bitflags! {
+    pub struct MapFlags: u32 {
+	const READ = 1 << 0;
+	const WRITE = 1 << 1;
+	const EXECUTE = 1 << 2;
+	const USER = 1 << 3;
+	const GLOBAL = 1 << 4;
+	const CACHED = 1 << 5;
+	const DEVICE = 1 << 6;
+    }
+}
+
+/// User space pointer wrapper for safe kernel-user space data transfer
+#[derive(Debug, Clone, Copy)]
+pub struct UserPtr<T> {
+	ptr: *mut T,
+}
+
+impl<T> UserPtr<T> {
+	/// Create a new UserPtr with validation
+	pub fn new(ptr: *mut T) -> Result<Self> {
+		if ptr.is_null() {
+			return Err(Error::InvalidArgument);
+		}
+		// TODO: Add proper user space validation
+		Ok(Self { ptr })
+	}
+
+	/// Create a new UserPtr from const pointer
+	pub fn from_const(ptr: *const T) -> Result<Self> {
+		Self::new(ptr as *mut T)
+	}
+
+	/// Get the raw pointer
+	pub fn as_ptr(&self) -> *mut T {
+		self.ptr
+	}
+
+	/// Cast to different type
+	pub fn cast<U>(&self) -> UserPtr<U> {
+		UserPtr {
+			ptr: self.ptr as *mut U,
+		}
+	}
+
+	/// Check if the pointer is null
+	pub fn is_null(&self) -> bool {
+		self.ptr.is_null()
+	}
+
+	/// Write data to user space
+	pub fn write(&self, data: T) -> Result<()> {
+		// TODO: Implement proper user space access validation
+		// For now, this is a stub
+		if self.ptr.is_null() {
+			return Err(Error::InvalidArgument);
+		}
+
+		// In a real kernel, this would use copy_to_user or similar
+		// For now, we'll use unsafe direct write (this is NOT safe for real use)
+		unsafe {
+			core::ptr::write(self.ptr, data);
+		}
+		Ok(())
+	}
+}
+
+/// User space slice pointer for array-like data
+#[derive(Debug, Clone, Copy)]
+pub struct UserSlicePtr {
+	ptr: *mut u8,
+	len: usize,
+}
+
+impl UserSlicePtr {
+	/// Create a new UserSlicePtr (unsafe as it's not validated)
+	pub unsafe fn new(ptr: *mut u8, len: usize) -> Self {
+		Self { ptr, len }
+	}
+
+	/// Get the raw pointer
+	pub fn as_ptr(&self) -> *mut u8 {
+		self.ptr
+	}
+
+	/// Get the length
+	pub fn len(&self) -> usize {
+		self.len
+	}
+
+	/// Check if empty
+	pub fn is_empty(&self) -> bool {
+		self.len == 0
+	}
+
+	/// Copy data from a slice to user space
+	pub fn copy_from_slice(&self, data: &[u8]) -> Result<()> {
+		// TODO: Implement proper user space access validation
+		// For now, this is a stub
+		if self.ptr.is_null() {
+			return Err(Error::InvalidArgument);
+		}
+
+		let copy_len = core::cmp::min(self.len, data.len());
+
+		// In a real kernel, this would use copy_to_user or similar
+		// For now, we'll use unsafe direct copy (this is NOT safe for real use)
+		unsafe {
+			core::ptr::copy_nonoverlapping(data.as_ptr(), self.ptr, copy_len);
+		}
+		Ok(())
+	}
+
+	/// Copy data from user space to a slice
+	pub fn copy_to_slice(&self, data: &mut [u8]) -> Result<()> {
+		// TODO: Implement proper user space access validation
+		// For now, this is a stub
+		if self.ptr.is_null() {
+			return Err(Error::InvalidArgument);
+		}
+
+		let copy_len = core::cmp::min(self.len, data.len());
+
+		// In a real kernel, this would use copy_from_user or similar
+		// For now, we'll use unsafe direct copy (this is NOT safe for real use)
+		unsafe {
+			core::ptr::copy_nonoverlapping(self.ptr, data.as_mut_ptr(), copy_len);
+		}
+		Ok(())
+	}
+}
+
+/// Copy data to user space
+pub fn copy_to_user(user_ptr: UserPtr<u8>, data: &[u8]) -> Result<()> {
+	// TODO: Implement proper user space access validation
+	// This should check if the user pointer is valid and accessible
+
+	if user_ptr.ptr.is_null() {
+		return Err(Error::InvalidArgument);
+	}
+
+	// In a real kernel, this would use proper copy_to_user with page fault handling
+	// For now, we'll use unsafe direct copy (NOT safe for real use)
+	unsafe {
+		core::ptr::copy_nonoverlapping(data.as_ptr(), user_ptr.ptr, data.len());
+	}
+	Ok(())
+}
+
+/// Copy data from user space
+pub fn copy_from_user(data: &mut [u8], user_ptr: UserPtr<u8>) -> Result<()> {
+	// TODO: Implement proper user space access validation
+	// This should check if the user pointer is valid and accessible
+
+	if user_ptr.ptr.is_null() {
+		return Err(Error::InvalidArgument);
+	}
+
+	// In a real kernel, this would use proper copy_from_user with page fault
+	// handling For now, we'll use unsafe direct copy (NOT safe for real use)
+	unsafe {
+		core::ptr::copy_nonoverlapping(user_ptr.ptr, data.as_mut_ptr(), data.len());
+	}
+	Ok(())
+}
+
+/// Copy a string from user space
+pub fn copy_string_from_user(user_ptr: UserPtr<u8>, max_len: usize) -> Result<String> {
+	// TODO: Implement proper user space access validation
+
+	if user_ptr.ptr.is_null() {
+		return Err(Error::InvalidArgument);
+	}
+
+	let mut buffer = alloc::vec![0u8; max_len];
+	let mut len = 0;
+
+	// Copy byte by byte until null terminator or max length
+	unsafe {
+		for i in 0..max_len {
+			let byte = *user_ptr.ptr.add(i);
+			if byte == 0 {
+				break;
+			}
+			buffer[i] = byte;
+			len += 1;
+		}
+	}
+
+	buffer.truncate(len);
+	String::from_utf8(buffer).map_err(|_| Error::InvalidArgument)
+}
+
+/// Memory mapping area structure
+#[derive(Debug, Clone)]
+pub struct VmaArea {
+	pub vm_start: VirtAddr,
+	pub vm_end: VirtAddr,
+	pub vm_prot: u32,
+	pub vm_flags: u32,
+}
+
+impl VmaArea {
+	pub fn new(start: VirtAddr, end: VirtAddr, prot: u32) -> Self {
+		Self {
+			vm_start: start,
+			vm_end: end,
+			vm_prot: prot,
+			vm_flags: 0,
+		}
+	}
+}
+
+/// Allocate virtual memory for mmap
+pub fn allocate_virtual_memory(size: u64, prot: u32, flags: u32) -> Result<VmaArea> {
+	use crate::memory::kmalloc::kmalloc;
+
+	// Allocate physical pages first
+	let pages_needed = (size + 4095) / 4096;
+	let phys_addr = kmalloc(size as usize)?;
+
+	// Find a free virtual address range
+	let virt_addr = find_free_virtual_range(size)?;
+
+	// Map the pages (simplified implementation)
+	map_pages(virt_addr, PhysAddr::new(phys_addr as usize), size, prot)?;
+
+	Ok(VmaArea::new(
+		virt_addr,
+		VirtAddr::new(virt_addr.as_usize() + size as usize),
+		prot,
+	))
+}
+
+/// Free virtual memory
+pub fn free_virtual_memory(addr: VirtAddr, size: u64) -> Result<()> {
+	// Unmap pages
+	unmap_pages(addr, size)?;
+
+	// Free physical memory (simplified)
+	crate::memory::kmalloc::kfree(addr.as_usize() as *mut u8);
+
+	Ok(())
+}
+
+/// Find a free virtual address range
+fn find_free_virtual_range(size: u64) -> Result<VirtAddr> {
+	// Simplified implementation - start from user space
+	const USER_SPACE_START: usize = 0x400000; // 4MB
+	const USER_SPACE_END: usize = 0x80000000; // 2GB
+
+	let mut addr = USER_SPACE_START;
+	while addr + size as usize <= USER_SPACE_END {
+		// Check if range is free (simplified check)
+		if is_virtual_range_free(VirtAddr::new(addr), size) {
+			return Ok(VirtAddr::new(addr));
+		}
+		addr += 4096; // Page size
+	}
+
+	Err(Error::ENOMEM)
+}
+
+/// Check if virtual range is free
+pub fn is_virtual_range_free(_addr: VirtAddr, _size: u64) -> bool {
+	// Simplified implementation - assume it's free
+	// In a real implementation, this would check page tables
+	true
+}
+
+/// Map virtual pages to physical pages
+fn map_pages(virt: VirtAddr, phys: PhysAddr, size: u64, _prot: u32) -> Result<()> {
+	// Simplified page mapping
+	// In a real implementation, this would set up page table entries
+	crate::info!(
+		"Mapping virtual 0x{:x} to physical 0x{:x}, size: {}",
+		virt.as_usize(),
+		phys.as_usize(),
+		size
+	);
+	Ok(())
+}
+
+/// Unmap virtual pages
+fn unmap_pages(virt: VirtAddr, size: u64) -> Result<()> {
+	// Simplified page unmapping
+	crate::info!("Unmapping virtual 0x{:x}, size: {}", virt.as_usize(), size);
+	Ok(())
+}
+
+/// Heap management for brk syscall
+static mut HEAP_START: VirtAddr = VirtAddr::new(0);
+static mut HEAP_END: VirtAddr = VirtAddr::new(0);
+
+/// Get current heap end
+pub fn get_heap_end() -> VirtAddr {
+	unsafe { HEAP_END }
+}
+
+/// Set heap end
+pub fn set_heap_end(new_end: VirtAddr) -> Result<()> {
+	unsafe {
+		if HEAP_START.as_usize() == 0 {
+			// Initialize heap
+			HEAP_START = VirtAddr::new(0x10000000); // 256MB
+			HEAP_END = HEAP_START;
+		}
+
+		if new_end >= HEAP_START {
+			HEAP_END = new_end;
+			Ok(())
+		} else {
+			Err(Error::EINVAL)
+		}
+	}
+}
+
+/// Initialize heap management
+pub fn init_heap() -> Result<()> {
+	unsafe {
+		HEAP_START = VirtAddr::new(0x10000000); // 256MB
+		HEAP_END = HEAP_START;
+	}
+	Ok(())
+}

kernel/src/memory/page.rs

@@ -0,0 +1,233 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Page frame allocator
+
+use core::sync::atomic::{AtomicU32, Ordering};
+
+use crate::error::{Error, Result};
+use crate::sync::Spinlock;
+use crate::types::{Pfn, PhysAddr};
+
+/// Page structure - similar to Linux struct page
+#[derive(Debug)]
+pub struct Page {
+	/// Page frame number
+	pub pfn: Pfn,
+	/// Page flags
+	pub flags: AtomicU32,
+	/// Reference count
+	pub count: AtomicU32,
+	/// Virtual address if mapped
+	pub virtual_addr: Option<crate::types::VirtAddr>,
+}
+
+impl Page {
+	/// Create a new page
+	pub fn new(pfn: Pfn) -> Self {
+		Self {
+			pfn,
+			flags: AtomicU32::new(0),
+			count: AtomicU32::new(1),
+			virtual_addr: None,
+		}
+	}
+
+	/// Get physical address
+	pub fn phys_addr(&self) -> PhysAddr {
+		PhysAddr(self.pfn.0 * 4096) // Assuming 4KB pages
+	}
+
+	/// Get page flags
+	pub fn flags(&self) -> u32 {
+		self.flags.load(Ordering::Relaxed)
+	}
+
+	/// Set page flags
+	pub fn set_flags(&self, flags: u32) {
+		self.flags.store(flags, Ordering::Relaxed);
+	}
+
+	/// Get reference count
+	pub fn count(&self) -> u32 {
+		self.count.load(Ordering::Relaxed)
+	}
+
+	/// Increment reference count
+	pub fn get(&self) -> u32 {
+		self.count.fetch_add(1, Ordering::Relaxed) + 1
+	}
+
+	/// Decrement reference count
+	pub fn put(&self) -> u32 {
+		let old_count = self.count.fetch_sub(1, Ordering::Relaxed);
+		if old_count == 1 {
+			// Last reference - page can be freed
+			// TODO: Add to free list
+		}
+		old_count - 1
+	}
+}
+
+/// Page flags (Linux compatible)
+pub mod page_flags {
+	pub const PG_LOCKED: u32 = 0;
+	pub const PG_ERROR: u32 = 1;
+	pub const PG_REFERENCED: u32 = 2;
+	pub const PG_UPTODATE: u32 = 3;
+	pub const PG_DIRTY: u32 = 4;
+	pub const PG_LRU: u32 = 5;
+	pub const PG_ACTIVE: u32 = 6;
+	pub const PG_SLAB: u32 = 7;
+	pub const PG_OWNER_PRIV_1: u32 = 8;
+	pub const PG_ARCH_1: u32 = 9;
+	pub const PG_RESERVED: u32 = 10;
+	pub const PG_PRIVATE: u32 = 11;
+	pub const PG_PRIVATE_2: u32 = 12;
+	pub const PG_WRITEBACK: u32 = 13;
+	pub const PG_HEAD: u32 = 14;
+	pub const PG_SWAPCACHE: u32 = 15;
+	pub const PG_MAPPEDTODISK: u32 = 16;
+	pub const PG_RECLAIM: u32 = 17;
+	pub const PG_SWAPBACKED: u32 = 18;
+	pub const PG_UNEVICTABLE: u32 = 19;
+}
+
+/// Page frame allocator
+pub static PAGE_ALLOCATOR: Spinlock<PageAllocator> = Spinlock::new(PageAllocator::new());
+
+/// Page allocator implementation
+pub struct PageAllocator {
+	free_list_head: Option<PhysAddr>,
+	total_pages: usize,
+	allocated_pages: usize,
+	free_count: usize,
+}
+
+impl PageAllocator {
+	pub const fn new() -> Self {
+		Self {
+			free_list_head: None,
+			total_pages: 0,
+			allocated_pages: 0,
+			free_count: 0,
+		}
+	}
+
+	/// Add a range of pages to the free list
+	pub fn add_free_range(&mut self, start: Pfn, count: usize) {
+		// Safety: Only add pages that are within the identity-mapped region (0-1GB)
+		// Boot assembly maps 0-1GB with 2MB pages
+		const MAX_IDENTITY_MAPPED_PFN: usize = (1024 * 1024 * 1024) / 4096; // 1GB / 4KB
+
+		let safe_count = if start.0 >= MAX_IDENTITY_MAPPED_PFN {
+			// Start is beyond identity mapping, skip entirely
+			return;
+		} else if start.0 + count > MAX_IDENTITY_MAPPED_PFN {
+			// Trim to stay within identity mapping
+			MAX_IDENTITY_MAPPED_PFN - start.0
+		} else {
+			count
+		};
+
+		for i in 0..safe_count {
+			let pfn = Pfn(start.0 + i);
+			let phys_addr = PhysAddr(pfn.0 * 4096);
+
+			// Store current head in the new page
+			// We can write to phys_addr because it's identity mapped
+			unsafe {
+				let ptr = phys_addr.0 as *mut u64;
+				*ptr = self.free_list_head.map(|a| a.0 as u64).unwrap_or(0);
+			}
+
+			// Update head
+			self.free_list_head = Some(phys_addr);
+		}
+		self.total_pages += safe_count;
+		self.free_count += safe_count;
+	}
+
+	/// Allocate a single page
+	fn alloc_page(&mut self) -> Result<Pfn> {
+		if let Some(head_addr) = self.free_list_head {
+			// Read next ptr from head
+			let next_addr_u64 = unsafe { *(head_addr.0 as *const u64) };
+
+			self.free_list_head = if next_addr_u64 == 0 {
+				None
+			} else {
+				Some(PhysAddr(next_addr_u64 as usize))
+			};
+
+			self.allocated_pages += 1;
+			self.free_count -= 1;
+			Ok(Pfn(head_addr.0 / 4096))
+		} else {
+			Err(Error::OutOfMemory)
+		}
+	}
+
+	/// Free a single page
+	fn free_page(&mut self, pfn: Pfn) {
+		let phys_addr = PhysAddr(pfn.0 * 4096);
+		unsafe {
+			let ptr = phys_addr.0 as *mut u64;
+			*ptr = self.free_list_head.map(|a| a.0 as u64).unwrap_or(0);
+		}
+		self.free_list_head = Some(phys_addr);
+		self.allocated_pages -= 1;
+		self.free_count += 1;
+	}
+
+	/// Get statistics
+	fn stats(&self) -> (usize, usize, usize) {
+		(self.total_pages, self.allocated_pages, self.free_count)
+	}
+}
+
+/// Initialize the page allocator
+pub fn init() -> Result<()> {
+	// Page allocator stub - no actual pages initialized yet
+	Ok(())
+}
+
+/// Add a range of free pages by physical address
+pub fn add_free_range(start_addr: PhysAddr, end_addr: PhysAddr) -> Result<()> {
+	let start_pfn = Pfn::from_phys_addr(start_addr);
+	let end_pfn = Pfn::from_phys_addr(end_addr);
+
+	if end_pfn.0 <= start_pfn.0 {
+		return Err(crate::error::Error::InvalidArgument);
+	}
+
+	let count = end_pfn.0 - start_pfn.0;
+	let mut allocator = PAGE_ALLOCATOR.lock();
+	allocator.add_free_range(start_pfn, count);
+
+	Ok(())
+}
+
+/// Allocate a page of physical memory
+pub fn alloc_page() -> Result<PhysAddr> {
+	let mut allocator = PAGE_ALLOCATOR.lock();
+	let pfn = allocator.alloc_page()?;
+	Ok(pfn.to_phys_addr())
+}
+
+/// Allocate a page of physical memory (alias for alloc_page)
+pub fn allocate_page() -> Result<PhysAddr> {
+	alloc_page()
+}
+
+/// Free a page of physical memory
+pub fn free_page(addr: PhysAddr) {
+	let pfn = Pfn::from_phys_addr(addr);
+	let mut allocator = PAGE_ALLOCATOR.lock();
+	allocator.free_page(pfn);
+}
+
+/// Get page allocator statistics
+pub fn stats() -> (usize, usize, usize) {
+	let allocator = PAGE_ALLOCATOR.lock();
+	allocator.stats()
+}

kernel/src/memory/page_table.rs

@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Page table management for x86_64
+
+use core::arch::asm;
+
+use crate::error::{Error, Result};
+use crate::memory::allocator::{alloc_pages, free_pages, GfpFlags, PageFrameNumber};
+use crate::types::{PhysAddr, VirtAddr, PAGE_SIZE};
+
+/// Page table entry flags
+#[derive(Debug, Clone, Copy)]
+pub struct PageTableFlags(pub u64);
+
+impl PageTableFlags {
+	pub const PRESENT: Self = Self(1 << 0);
+	pub const WRITABLE: Self = Self(1 << 1);
+	pub const USER_ACCESSIBLE: Self = Self(1 << 2);
+	pub const WRITE_THROUGH: Self = Self(1 << 3);
+	pub const NO_CACHE: Self = Self(1 << 4);
+	pub const ACCESSED: Self = Self(1 << 5);
+	pub const DIRTY: Self = Self(1 << 6);
+	pub const HUGE_PAGE: Self = Self(1 << 7);
+	pub const GLOBAL: Self = Self(1 << 8);
+	pub const NO_EXECUTE: Self = Self(1 << 63);
+
+	pub fn empty() -> Self {
+		Self(0)
+	}
+
+	pub fn kernel_page() -> Self {
+		Self::PRESENT | Self::WRITABLE
+	}
+
+	pub fn user_page() -> Self {
+		Self::PRESENT | Self::WRITABLE | Self::USER_ACCESSIBLE
+	}
+
+	pub fn contains(self, flag: Self) -> bool {
+		self.0 & flag.0 != 0
+	}
+}
+
+impl core::ops::BitOr for PageTableFlags {
+	type Output = Self;
+
+	fn bitor(self, rhs: Self) -> Self::Output {
+		Self(self.0 | rhs.0)
+	}
+}
+
+impl core::ops::BitOrAssign for PageTableFlags {
+	fn bitor_assign(&mut self, rhs: Self) {
+		self.0 |= rhs.0;
+	}
+}
+
+/// Page table entry
+#[repr(transparent)]
+#[derive(Debug, Clone, Copy)]
+pub struct PageTableEntry(pub u64);
+
+impl PageTableEntry {
+	pub fn new() -> Self {
+		Self(0)
+	}
+
+	pub fn is_present(self) -> bool {
+		self.0 & 1 != 0
+	}
+
+	pub fn set_frame(self, frame: PageFrameNumber, flags: PageTableFlags) -> Self {
+		let addr = frame.to_phys_addr().as_usize() as u64;
+		Self((addr & !0xfff) | flags.0)
+	}
+
+	pub fn frame(self) -> Option<PageFrameNumber> {
+		if self.is_present() {
+			Some(PageFrameNumber::from_phys_addr(PhysAddr::new(
+				(self.0 & !0xfff) as usize,
+			)))
+		} else {
+			None
+		}
+	}
+
+	pub fn flags(self) -> PageTableFlags {
+		PageTableFlags(self.0 & 0xfff)
+	}
+}
+
+/// Page table with 512 entries (x86_64)
+#[repr(align(4096))]
+pub struct PageTable {
+	entries: [PageTableEntry; 512],
+}
+
+impl PageTable {
+	pub fn new() -> Self {
+		Self {
+			entries: [PageTableEntry::new(); 512],
+		}
+	}
+
+	pub fn zero(&mut self) {
+		for entry in &mut self.entries {
+			*entry = PageTableEntry::new();
+		}
+	}
+
+	pub fn entry(&mut self, index: usize) -> &mut PageTableEntry {
+		&mut self.entries[index]
+	}
+
+	pub fn entry_ref(&self, index: usize) -> &PageTableEntry {
+		&self.entries[index]
+	}
+}
+
+/// Page table manager
+pub struct PageTableManager {
+	root_table: PhysAddr,
+}
+
+impl PageTableManager {
+	pub fn new() -> Result<Self> {
+		// Allocate a page for the root page table (PML4)
+		let pfn = alloc_pages(0, GfpFlags::KERNEL)?;
+		let root_table = pfn.to_phys_addr();
+
+		// Zero the root table
+		unsafe {
+			let table = root_table.as_usize() as *mut PageTable;
+			(*table).zero();
+		}
+
+		Ok(Self { root_table })
+	}
+
+	pub fn root_table_addr(&self) -> PhysAddr {
+		self.root_table
+	}
+
+	/// Map a virtual page to a physical page
+	pub fn map_page(
+		&mut self,
+		virt_addr: VirtAddr,
+		phys_addr: PhysAddr,
+		flags: PageTableFlags,
+	) -> Result<()> {
+		let virt_page = virt_addr.as_usize() / PAGE_SIZE;
+		let pfn = PageFrameNumber::from_phys_addr(phys_addr);
+
+		// Extract page table indices from virtual address
+		let pml4_index = (virt_page >> 27) & 0x1ff;
+		let pdp_index = (virt_page >> 18) & 0x1ff;
+		let pd_index = (virt_page >> 9) & 0x1ff;
+		let pt_index = virt_page & 0x1ff;
+
+		// Walk and create page tables as needed
+		let pml4 = unsafe { &mut *(self.root_table.as_usize() as *mut PageTable) };
+
+		// Get or create PDP
+		let pdp_addr = if pml4.entry_ref(pml4_index).is_present() {
+			pml4.entry_ref(pml4_index).frame().unwrap().to_phys_addr()
+		} else {
+			let pdp_pfn = alloc_pages(0, GfpFlags::KERNEL)?;
+			let pdp_addr = pdp_pfn.to_phys_addr();
+			unsafe {
+				let pdp_table = pdp_addr.as_usize() as *mut PageTable;
+				(*pdp_table).zero();
+			}
+			*pml4.entry(pml4_index) = PageTableEntry::new()
+				.set_frame(pdp_pfn, PageTableFlags::kernel_page());
+			pdp_addr
+		};
+
+		// Get or create PD
+		let pdp = unsafe { &mut *(pdp_addr.as_usize() as *mut PageTable) };
+		let pd_addr = if pdp.entry_ref(pdp_index).is_present() {
+			pdp.entry_ref(pdp_index).frame().unwrap().to_phys_addr()
+		} else {
+			let pd_pfn = alloc_pages(0, GfpFlags::KERNEL)?;
+			let pd_addr = pd_pfn.to_phys_addr();
+			unsafe {
+				let pd_table = pd_addr.as_usize() as *mut PageTable;
+				(*pd_table).zero();
+			}
+			*pdp.entry(pdp_index) = PageTableEntry::new()
+				.set_frame(pd_pfn, PageTableFlags::kernel_page());
+			pd_addr
+		};
+
+		// Get or create PT
+		let pd = unsafe { &mut *(pd_addr.as_usize() as *mut PageTable) };
+		let pt_addr = if pd.entry_ref(pd_index).is_present() {
+			pd.entry_ref(pd_index).frame().unwrap().to_phys_addr()
+		} else {
+			let pt_pfn = alloc_pages(0, GfpFlags::KERNEL)?;
+			let pt_addr = pt_pfn.to_phys_addr();
+			unsafe {
+				let pt_table = pt_addr.as_usize() as *mut PageTable;
+				(*pt_table).zero();
+			}
+			*pd.entry(pd_index) = PageTableEntry::new()
+				.set_frame(pt_pfn, PageTableFlags::kernel_page());
+			pt_addr
+		};
+
+		// Set the final page mapping
+		let pt = unsafe { &mut *(pt_addr.as_usize() as *mut PageTable) };
+		*pt.entry(pt_index) = PageTableEntry::new().set_frame(pfn, flags);
+
+		// Flush TLB for this page
+		unsafe {
+			asm!("invlpg [{}]", in(reg) virt_addr.as_usize(), options(nostack, preserves_flags));
+		}
+
+		Ok(())
+	}
+
+	/// Unmap a virtual page
+	pub fn unmap_page(&mut self, virt_addr: VirtAddr) -> Result<()> {
+		let virt_page = virt_addr.as_usize() / PAGE_SIZE;
+
+		// Extract page table indices
+		let pml4_index = (virt_page >> 27) & 0x1ff;
+		let pdp_index = (virt_page >> 18) & 0x1ff;
+		let pd_index = (virt_page >> 9) & 0x1ff;
+		let pt_index = virt_page & 0x1ff;
+
+		// Walk page tables
+		let pml4 = unsafe { &mut *(self.root_table.as_usize() as *mut PageTable) };
+
+		if !pml4.entry_ref(pml4_index).is_present() {
+			return Err(Error::InvalidArgument);
+		}
+
+		let pdp_addr = pml4.entry_ref(pml4_index).frame().unwrap().to_phys_addr();
+		let pdp = unsafe { &mut *(pdp_addr.as_usize() as *mut PageTable) };
+
+		if !pdp.entry_ref(pdp_index).is_present() {
+			return Err(Error::InvalidArgument);
+		}
+
+		let pd_addr = pdp.entry_ref(pdp_index).frame().unwrap().to_phys_addr();
+		let pd = unsafe { &mut *(pd_addr.as_usize() as *mut PageTable) };
+
+		if !pd.entry_ref(pd_index).is_present() {
+			return Err(Error::InvalidArgument);
+		}
+
+		let pt_addr = pd.entry_ref(pd_index).frame().unwrap().to_phys_addr();
+		let pt = unsafe { &mut *(pt_addr.as_usize() as *mut PageTable) };
+
+		// Clear the page table entry
+		*pt.entry(pt_index) = PageTableEntry::new();
+
+		// Flush TLB for this page
+		unsafe {
+			asm!("invlpg [{}]", in(reg) virt_addr.as_usize(), options(nostack, preserves_flags));
+		}
+
+		Ok(())
+	}
+
+	/// Switch to this page table
+	pub fn switch_to(&self) {
+		unsafe {
+			asm!("mov cr3, {}", in(reg) self.root_table.as_usize(), options(nostack, preserves_flags));
+		}
+	}
+}

kernel/src/memory/vmalloc.rs

@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Virtual memory allocation
+
+use alloc::collections::BTreeMap;
+use core::ptr::NonNull;
+
+use crate::error::{Error, Result};
+use crate::memory::allocator::{alloc_pages, free_pages, GfpFlags, PageFrameNumber};
+use crate::memory::page_table::{PageTableFlags, PageTableManager};
+use crate::sync::Spinlock;
+use crate::types::{PhysAddr, VirtAddr};
+
+/// Virtual memory area descriptor
+#[derive(Debug, Clone)]
+struct VmallocArea {
+	start: VirtAddr,
+	end: VirtAddr,
+	size: usize,
+	pages: alloc::vec::Vec<PhysAddr>,
+}
+
+/// Vmalloc allocator
+struct VmallocAllocator {
+	areas: BTreeMap<usize, VmallocArea>,
+	next_addr: usize,
+	page_table: Option<PageTableManager>,
+}
+
+impl VmallocAllocator {
+	const fn new() -> Self {
+		Self {
+			areas: BTreeMap::new(),
+			next_addr: 0xFFFF_8000_0000_0000, // Kernel vmalloc area start
+			page_table: None,
+		}
+	}
+
+	fn init(&mut self) -> Result<()> {
+		self.page_table = Some(PageTableManager::new()?);
+		Ok(())
+	}
+
+	fn allocate(&mut self, size: usize) -> Result<VirtAddr> {
+		if size == 0 {
+			return Err(Error::InvalidArgument);
+		}
+
+		// Align size to page boundary
+		let aligned_size = (size + 4095) & !4095;
+		let pages_needed = aligned_size / 4096;
+
+		// Find virtual address space
+		let start_addr = self.find_free_area(aligned_size)?;
+		let end_addr = start_addr + aligned_size;
+
+		// Allocate physical pages
+		let mut pages = alloc::vec::Vec::new();
+		for _ in 0..pages_needed {
+			let pfn = alloc_pages(0, GfpFlags::KERNEL)?;
+			pages.push(pfn.to_phys_addr());
+		}
+
+		// Map virtual to physical pages
+		if let Some(ref mut page_table) = self.page_table {
+			for (i, &phys_addr) in pages.iter().enumerate() {
+				let virt_addr = VirtAddr::new(start_addr + i * 4096);
+				page_table.map_page(
+					virt_addr,
+					phys_addr,
+					PageTableFlags::kernel_page(),
+				)?;
+			}
+		}
+
+		let area = VmallocArea {
+			start: VirtAddr::new(start_addr),
+			end: VirtAddr::new(end_addr),
+			size: aligned_size,
+			pages,
+		};
+
+		self.areas.insert(start_addr, area);
+		Ok(VirtAddr::new(start_addr))
+	}
+
+	fn deallocate(&mut self, addr: VirtAddr) -> Result<()> {
+		let addr_usize = addr.as_usize();
+
+		if let Some(area) = self.areas.remove(&addr_usize) {
+			// Unmap pages from page tables
+			if let Some(ref mut page_table) = self.page_table {
+				for i in 0..(area.size / 4096) {
+					let virt_addr =
+						VirtAddr::new(area.start.as_usize() + i * 4096);
+					let _ = page_table.unmap_page(virt_addr);
+				}
+			}
+
+			// Free physical pages
+			for phys_addr in area.pages {
+				if let Some(_page_ptr) = NonNull::new(
+					phys_addr.as_usize() as *mut crate::memory::Page
+				) {
+					let pfn = PageFrameNumber::from_phys_addr(phys_addr);
+					free_pages(pfn, 0);
+				}
+			}
+
+			Ok(())
+		} else {
+			Err(Error::InvalidArgument)
+		}
+	}
+
+	fn find_free_area(&mut self, size: usize) -> Result<usize> {
+		// Simple linear search for free area
+		// In a real implementation, this would be more sophisticated
+		let mut addr = self.next_addr;
+
+		// Check if area is free
+		for (start, area) in &self.areas {
+			if addr >= *start && addr < area.end.as_usize() {
+				addr = area.end.as_usize();
+			}
+		}
+
+		self.next_addr = addr + size;
+		Ok(addr)
+	}
+
+	pub fn stats(&self) -> (usize, usize) {
+		let mut allocated_bytes = 0;
+		for (_, area) in &self.areas {
+			allocated_bytes += area.size;
+		}
+		(self.areas.len(), allocated_bytes)
+	}
+}
+
+static VMALLOC_ALLOCATOR: Spinlock<VmallocAllocator> = Spinlock::new(VmallocAllocator::new());
+
+/// Get vmalloc statistics
+pub fn get_stats() -> (usize, usize) {
+	let allocator = VMALLOC_ALLOCATOR.lock();
+	allocator.stats()
+}
+
+/// Allocate virtual memory
+pub fn vmalloc(size: usize) -> Result<VirtAddr> {
+	let mut allocator = VMALLOC_ALLOCATOR.lock();
+	allocator.allocate(size)
+}
+
+/// Free virtual memory
+pub fn vfree(addr: VirtAddr) {
+	let mut allocator = VMALLOC_ALLOCATOR.lock();
+	let _ = allocator.deallocate(addr);
+}
+
+/// Allocate zeroed virtual memory
+pub fn vzalloc(size: usize) -> Result<VirtAddr> {
+	let addr = vmalloc(size)?;
+
+	// Zero the memory
+	unsafe {
+		core::ptr::write_bytes(addr.as_usize() as *mut u8, 0, size);
+	}
+
+	Ok(addr)
+}
+
+/// Map physical memory into virtual space
+pub fn vmap_phys(phys_addr: PhysAddr, size: usize) -> Result<VirtAddr> {
+	let start_addr;
+	let aligned_size;
+	{
+		let mut allocator = VMALLOC_ALLOCATOR.lock();
+		if allocator.page_table.is_none() {
+			return Err(Error::NotInitialized);
+		}
+		aligned_size = (size + 4095) & !4095;
+		start_addr = allocator.find_free_area(aligned_size)?;
+	}
+
+	let mut allocator = VMALLOC_ALLOCATOR.lock();
+	let page_table = allocator.page_table.as_mut().unwrap();
+
+	// Map virtual to physical pages
+	let pages_needed = aligned_size / 4096;
+	for i in 0..pages_needed {
+		let virt_addr = VirtAddr::new(start_addr + i * 4096);
+		let phys_addr = PhysAddr::new(phys_addr.as_usize() + i * 4096);
+		page_table.map_page(
+			virt_addr,
+			phys_addr,
+			PageTableFlags::kernel_page() | PageTableFlags::NO_EXECUTE,
+		)?;
+	}
+
+	let end_addr = start_addr + aligned_size;
+	let area = VmallocArea {
+		start: VirtAddr::new(start_addr),
+		end: VirtAddr::new(end_addr),
+		size: aligned_size,
+		pages: alloc::vec![], // We don't own these pages
+	};
+
+	allocator.areas.insert(start_addr, area);
+	Ok(VirtAddr::new(start_addr))
+}
+
+pub fn vmap(pages: &[PhysAddr], count: usize) -> Result<VirtAddr> {
+	let size = count * 4096;
+	let mut allocator = VMALLOC_ALLOCATOR.lock();
+
+	// Find virtual address space
+	let start_addr = allocator.find_free_area(size)?;
+
+	let area = VmallocArea {
+		start: VirtAddr::new(start_addr),
+		end: VirtAddr::new(start_addr + size),
+		size,
+		pages: pages.to_vec(),
+	};
+
+	allocator.areas.insert(start_addr, area);
+
+	// TODO: Set up page table mappings
+
+	Ok(VirtAddr::new(start_addr))
+}
+
+/// Unmap virtual memory
+pub fn vunmap(addr: VirtAddr) {
+	vfree(addr);
+}
+
+/// Initialize vmalloc allocator
+pub fn init() -> Result<()> {
+	let mut allocator = VMALLOC_ALLOCATOR.lock();
+	allocator.init()
+}

kernel/src/module.rs

@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel module support
+
+use crate::error::Result;
+
+/// Module metadata
+pub struct ThisModule {
+	pub name: &'static str,
+	pub author: &'static str,
+	pub description: &'static str,
+	pub license: &'static str,
+}
+
+/// Trait for kernel modules
+pub trait Module: Sized {
+	/// Initialize the module
+	fn init(module: &'static ThisModule) -> Result<Self>;
+
+	/// Clean up the module
+	fn exit(module: &'static ThisModule) {
+		// Default implementation does nothing
+	}
+}

kernel/src/module_loader.rs

@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Dynamic module loading system
+
+use alloc::{
+	collections::BTreeMap,
+	string::{String, ToString},
+	vec::Vec,
+};
+
+use crate::error::Result;
+use crate::sync::Spinlock;
+use crate::{error, info, warn};
+
+/// Module state
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ModuleState {
+	Loading,
+	Live,
+	Coming,
+	Going,
+	Unloading,
+}
+
+/// Module descriptor
+#[derive(Debug)]
+pub struct Module {
+	pub name: String,
+	pub version: String,
+	pub description: String,
+	pub state: ModuleState,
+	pub init_fn: Option<fn() -> Result<()>>,
+	pub cleanup_fn: Option<fn()>,
+	pub reference_count: u32,
+	pub dependencies: Vec<String>,
+}
+
+impl Module {
+	pub fn new(name: String, version: String, description: String) -> Self {
+		Self {
+			name,
+			version,
+			description,
+			state: ModuleState::Loading,
+			init_fn: None,
+			cleanup_fn: None,
+			reference_count: 0,
+			dependencies: Vec::new(),
+		}
+	}
+
+	/// Set module functions
+	pub fn set_functions(&mut self, init_fn: fn() -> Result<()>, cleanup_fn: fn()) {
+		self.init_fn = Some(init_fn);
+		self.cleanup_fn = Some(cleanup_fn);
+	}
+
+	/// Add dependency
+	pub fn add_dependency(&mut self, dep: String) {
+		self.dependencies.push(dep);
+	}
+
+	/// Initialize the module
+	pub fn init(&mut self) -> Result<()> {
+		if let Some(init_fn) = self.init_fn {
+			self.state = ModuleState::Coming;
+			init_fn()?;
+			self.state = ModuleState::Live;
+			info!("Module {} initialized successfully", self.name);
+			Ok(())
+		} else {
+			warn!("Module {} has no init function", self.name);
+			self.state = ModuleState::Live;
+			Ok(())
+		}
+	}
+
+	/// Cleanup the module
+	pub fn cleanup(&mut self) {
+		if self.reference_count > 0 {
+			warn!(
+				"Module {} still has {} references",
+				self.name, self.reference_count
+			);
+			return;
+		}
+
+		self.state = ModuleState::Going;
+		if let Some(cleanup_fn) = self.cleanup_fn {
+			cleanup_fn();
+		}
+		self.state = ModuleState::Unloading;
+		info!("Module {} cleaned up", self.name);
+	}
+}
+
+/// Module subsystem
+static MODULE_SUBSYSTEM: Spinlock<ModuleSubsystem> = Spinlock::new(ModuleSubsystem::new());
+
+struct ModuleSubsystem {
+	modules: BTreeMap<String, Module>,
+	load_order: Vec<String>,
+}
+
+impl ModuleSubsystem {
+	const fn new() -> Self {
+		Self {
+			modules: BTreeMap::new(),
+			load_order: Vec::new(),
+		}
+	}
+
+	fn register_module(&mut self, mut module: Module) -> Result<()> {
+		// Check dependencies
+		for dep in &module.dependencies {
+			if !self.modules.contains_key(dep) {
+				error!("Module {} dependency {} not loaded", module.name, dep);
+				return Err(crate::error::Error::NotFound);
+			}
+
+			// Increment reference count of dependency
+			if let Some(dep_module) = self.modules.get_mut(dep) {
+				dep_module.reference_count += 1;
+			}
+		}
+
+		let name = module.name.clone();
+
+		// Initialize the module
+		module.init()?;
+
+		// Add to registry
+		self.modules.insert(name.clone(), module);
+		self.load_order.push(name);
+
+		Ok(())
+	}
+
+	fn unload_module(&mut self, name: &str) -> Result<()> {
+		if let Some(mut module) = self.modules.remove(name) {
+			// Decrement reference counts of dependencies
+			for dep in &module.dependencies {
+				if let Some(dep_module) = self.modules.get_mut(dep) {
+					if dep_module.reference_count > 0 {
+						dep_module.reference_count -= 1;
+					}
+				}
+			}
+
+			// Cleanup module
+			module.cleanup();
+
+			// Remove from load order
+			self.load_order.retain(|n| n != name);
+
+			info!("Module {} unloaded", name);
+			Ok(())
+		} else {
+			error!("Module {} not found", name);
+			Err(crate::error::Error::NotFound)
+		}
+	}
+
+	fn get_module(&self, name: &str) -> Option<&Module> {
+		self.modules.get(name)
+	}
+
+	fn list_modules(&self) -> Vec<&Module> {
+		self.modules.values().collect()
+	}
+}
+
+/// Initialize module subsystem
+pub fn init_modules() -> Result<()> {
+	info!("Initializing module subsystem");
+
+	// Register built-in modules
+	register_builtin_modules()?;
+
+	info!("Module subsystem initialized");
+	Ok(())
+}
+
+/// Register a module
+pub fn register_module(module: Module) -> Result<()> {
+	let mut subsystem = MODULE_SUBSYSTEM.lock();
+	subsystem.register_module(module)
+}
+
+/// Unload a module
+pub fn unload_module(name: &str) -> Result<()> {
+	let mut subsystem = MODULE_SUBSYSTEM.lock();
+	subsystem.unload_module(name)
+}
+
+/// Get module information
+pub fn get_module_info(name: &str) -> Option<(String, String, String, ModuleState)> {
+	let subsystem = MODULE_SUBSYSTEM.lock();
+	if let Some(module) = subsystem.get_module(name) {
+		Some((
+			module.name.clone(),
+			module.version.clone(),
+			module.description.clone(),
+			module.state,
+		))
+	} else {
+		None
+	}
+}
+
+/// List all modules
+pub fn list_modules() -> Vec<(String, String, String, ModuleState, u32)> {
+	let subsystem = MODULE_SUBSYSTEM.lock();
+	subsystem
+		.list_modules()
+		.into_iter()
+		.map(|m| {
+			(
+				m.name.clone(),
+				m.version.clone(),
+				m.description.clone(),
+				m.state,
+				m.reference_count,
+			)
+		})
+		.collect()
+}
+
+/// Register built-in modules
+fn register_builtin_modules() -> Result<()> {
+	// Test module
+	let mut test_module = Module::new(
+		"test".to_string(),
+		"1.0.0".to_string(),
+		"Test module for demonstration".to_string(),
+	);
+	test_module.set_functions(test_module_init, test_module_cleanup);
+	register_module(test_module)?;
+
+	// Console module
+	let mut console_module = Module::new(
+		"console".to_string(),
+		"1.0.0".to_string(),
+		"Console output module".to_string(),
+	);
+	console_module.set_functions(console_module_init, console_module_cleanup);
+	register_module(console_module)?;
+
+	// Network module (depends on console)
+	let mut network_module = Module::new(
+		"network".to_string(),
+		"1.0.0".to_string(),
+		"Basic networking module".to_string(),
+	);
+	network_module.add_dependency("console".to_string());
+	network_module.set_functions(network_module_init, network_module_cleanup);
+	register_module(network_module)?;
+
+	Ok(())
+}
+
+// Built-in module functions
+fn test_module_init() -> Result<()> {
+	info!("Test module loaded");
+	Ok(())
+}
+
+fn test_module_cleanup() {
+	info!("Test module unloaded");
+}
+
+fn console_module_init() -> Result<()> {
+	info!("Console module loaded");
+	Ok(())
+}
+
+fn console_module_cleanup() {
+	info!("Console module unloaded");
+}
+
+fn network_module_init() -> Result<()> {
+	info!("Network module loaded");
+	Ok(())
+}
+
+fn network_module_cleanup() {
+	info!("Network module unloaded");
+}
+
+/// Test module loading functionality
+pub fn test_module_system() -> Result<()> {
+	info!("Testing module system");
+
+	// Create and load a test module
+	let mut dynamic_test = Module::new(
+		"dynamic_test".to_string(),
+		"0.1.0".to_string(),
+		"Dynamic test module".to_string(),
+	);
+	dynamic_test.set_functions(
+		|| {
+			info!("Dynamic test module init");
+			Ok(())
+		},
+		|| {
+			info!("Dynamic test module cleanup");
+		},
+	);
+
+	register_module(dynamic_test)?;
+
+	// List modules
+	let modules = list_modules();
+	info!("Loaded modules:");
+	for (name, version, desc, state, refs) in modules {
+		info!(
+			"  {} v{}: {} (state: {:?}, refs: {})",
+			name, version, desc, state, refs
+		);
+	}
+
+	// Unload the test module
+	unload_module("dynamic_test")?;
+
+	info!("Module system test completed");
+	Ok(())
+}

kernel/src/network.rs

@@ -0,0 +1,727 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Network stack implementation
+
+use alloc::{
+	boxed::Box,
+	collections::BTreeMap,
+	collections::VecDeque,
+	string::{String, ToString},
+	vec::Vec,
+};
+use core::fmt;
+
+use crate::error::{Error, Result};
+use crate::sync::Spinlock;
+
+/// Network protocol types
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum ProtocolType {
+	Ethernet = 0x0001,
+	IPv4 = 0x0800,
+	IPv6 = 0x86DD,
+	ARP = 0x0806,
+	TCP = 6,
+	UDP = 17,
+	ICMP = 2, // Different value to avoid conflict with Ethernet
+	ICMPv6 = 58,
+}
+
+/// MAC address (6 bytes)
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct MacAddress([u8; 6]);
+
+impl MacAddress {
+	pub const fn new(bytes: [u8; 6]) -> Self {
+		Self(bytes)
+	}
+
+	pub const fn broadcast() -> Self {
+		Self([0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF])
+	}
+
+	pub const fn zero() -> Self {
+		Self([0, 0, 0, 0, 0, 0])
+	}
+
+	pub fn bytes(&self) -> &[u8; 6] {
+		&self.0
+	}
+
+	pub fn is_broadcast(&self) -> bool {
+		*self == Self::broadcast()
+	}
+
+	pub fn is_multicast(&self) -> bool {
+		(self.0[0] & 0x01) != 0
+	}
+}
+
+impl fmt::Display for MacAddress {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		write!(
+			f,
+			"{:02x}:{:02x}:{:02x}:{:02x}:{:02x}:{:02x}",
+			self.0[0], self.0[1], self.0[2], self.0[3], self.0[4], self.0[5]
+		)
+	}
+}
+
+/// IPv4 address
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
+pub struct Ipv4Address([u8; 4]);
+
+impl Ipv4Address {
+	pub const fn new(a: u8, b: u8, c: u8, d: u8) -> Self {
+		Self([a, b, c, d])
+	}
+
+	pub const fn from_bytes(bytes: [u8; 4]) -> Self {
+		Self(bytes)
+	}
+
+	pub const fn localhost() -> Self {
+		Self([127, 0, 0, 1])
+	}
+
+	pub const fn broadcast() -> Self {
+		Self([255, 255, 255, 255])
+	}
+
+	pub const fn any() -> Self {
+		Self([0, 0, 0, 0])
+	}
+
+	pub fn bytes(&self) -> &[u8; 4] {
+		&self.0
+	}
+
+	pub fn to_u32(&self) -> u32 {
+		u32::from_be_bytes(self.0)
+	}
+
+	pub fn from_u32(addr: u32) -> Self {
+		Self(addr.to_be_bytes())
+	}
+
+	pub fn is_private(&self) -> bool {
+		matches!(self.0, [10, ..] | [172, 16..=31, ..] | [192, 168, ..])
+	}
+
+	pub fn is_multicast(&self) -> bool {
+		(self.0[0] & 0xF0) == 0xE0
+	}
+
+	pub fn is_broadcast(&self) -> bool {
+		*self == Self::broadcast()
+	}
+}
+
+impl fmt::Display for Ipv4Address {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		write!(f, "{}.{}.{}.{}", self.0[0], self.0[1], self.0[2], self.0[3])
+	}
+}
+
+/// Network packet buffer
+#[derive(Debug, Clone)]
+pub struct NetworkBuffer {
+	data: Vec<u8>,
+	len: usize,
+	protocol: ProtocolType,
+	source_mac: Option<MacAddress>,
+	dest_mac: Option<MacAddress>,
+	source_ip: Option<Ipv4Address>,
+	dest_ip: Option<Ipv4Address>,
+	source_port: Option<u16>,
+	dest_port: Option<u16>,
+}
+
+impl NetworkBuffer {
+	pub fn new(capacity: usize) -> Self {
+		Self {
+			data: Vec::with_capacity(capacity),
+			len: 0,
+			protocol: ProtocolType::Ethernet,
+			source_mac: None,
+			dest_mac: None,
+			source_ip: None,
+			dest_ip: None,
+			source_port: None,
+			dest_port: None,
+		}
+	}
+
+	pub fn from_data(data: Vec<u8>) -> Self {
+		let len = data.len();
+		Self {
+			data,
+			len,
+			protocol: ProtocolType::Ethernet,
+			source_mac: None,
+			dest_mac: None,
+			source_ip: None,
+			dest_ip: None,
+			source_port: None,
+			dest_port: None,
+		}
+	}
+
+	pub fn data(&self) -> &[u8] {
+		&self.data[..self.len]
+	}
+
+	pub fn data_mut(&mut self) -> &mut [u8] {
+		&mut self.data[..self.len]
+	}
+
+	pub fn len(&self) -> usize {
+		self.len
+	}
+
+	pub fn push(&mut self, byte: u8) -> Result<()> {
+		if self.len >= self.data.capacity() {
+			return Err(Error::OutOfMemory);
+		}
+		if self.len >= self.data.len() {
+			self.data.push(byte);
+		} else {
+			self.data[self.len] = byte;
+		}
+		self.len += 1;
+		Ok(())
+	}
+
+	pub fn extend_from_slice(&mut self, data: &[u8]) -> Result<()> {
+		if self.len + data.len() > self.data.capacity() {
+			return Err(Error::OutOfMemory);
+		}
+		for &byte in data {
+			self.push(byte)?;
+		}
+		Ok(())
+	}
+
+	pub fn set_protocol(&mut self, protocol: ProtocolType) {
+		self.protocol = protocol;
+	}
+
+	pub fn set_mac_addresses(&mut self, source: MacAddress, dest: MacAddress) {
+		self.source_mac = Some(source);
+		self.dest_mac = Some(dest);
+	}
+
+	pub fn set_ip_addresses(&mut self, source: Ipv4Address, dest: Ipv4Address) {
+		self.source_ip = Some(source);
+		self.dest_ip = Some(dest);
+	}
+
+	pub fn set_ports(&mut self, source: u16, dest: u16) {
+		self.source_port = Some(source);
+		self.dest_port = Some(dest);
+	}
+}
+
+/// Network interface
+pub trait NetworkInterface: Send + Sync {
+	fn name(&self) -> &str;
+	fn ip_address(&self) -> Option<Ipv4Address>;
+	fn mac_address(&self) -> MacAddress;
+	fn mtu(&self) -> u16;
+	fn is_up(&self) -> bool;
+
+	fn send_packet(&mut self, buffer: &NetworkBuffer) -> Result<()>;
+	fn receive_packet(&mut self) -> Result<Option<NetworkBuffer>>;
+
+	fn set_up(&mut self, up: bool) -> Result<()>;
+	fn set_mac_address(&mut self, mac: MacAddress) -> Result<()>;
+}
+
+/// Network interface statistics
+#[derive(Debug, Default, Clone)]
+pub struct InterfaceStats {
+	pub bytes_sent: u64,
+	pub bytes_received: u64,
+	pub packets_sent: u64,
+	pub packets_received: u64,
+	pub errors: u64,
+	pub dropped: u64,
+}
+
+/// A loopback network interface.
+#[derive(Debug)]
+pub struct LoopbackInterface {
+	rx_queue: VecDeque<NetworkBuffer>,
+	up: bool,
+}
+
+impl LoopbackInterface {
+	pub fn new() -> Self {
+		Self {
+			rx_queue: VecDeque::new(),
+			up: true,
+		}
+	}
+}
+
+impl NetworkInterface for LoopbackInterface {
+	fn name(&self) -> &str {
+		"lo"
+	}
+
+	fn ip_address(&self) -> Option<Ipv4Address> {
+		Some(Ipv4Address::localhost())
+	}
+
+	fn mac_address(&self) -> MacAddress {
+		MacAddress::zero()
+	}
+
+	fn mtu(&self) -> u16 {
+		65535
+	}
+
+	fn is_up(&self) -> bool {
+		self.up
+	}
+
+	fn send_packet(&mut self, buffer: &NetworkBuffer) -> Result<()> {
+		if !self.up {
+			return Err(Error::NetworkDown);
+		}
+		self.rx_queue.push_back(buffer.clone());
+		Ok(())
+	}
+
+	fn receive_packet(&mut self) -> Result<Option<NetworkBuffer>> {
+		if !self.up {
+			return Ok(None);
+		}
+		Ok(self.rx_queue.pop_front())
+	}
+
+	fn set_up(&mut self, up: bool) -> Result<()> {
+		self.up = up;
+		Ok(())
+	}
+
+	fn set_mac_address(&mut self, _mac: MacAddress) -> Result<()> {
+		// The loopback interface doesn't have a real MAC address.
+		Ok(())
+	}
+}
+
+/// Network stack
+struct PendingArpRequest {
+	packet: NetworkBuffer,
+	ip: Ipv4Address,
+	timestamp: u64,
+}
+
+pub struct NetworkStack {
+	interfaces: BTreeMap<String, Box<dyn NetworkInterface>>,
+	interface_stats: BTreeMap<String, InterfaceStats>,
+	routing_table: Vec<RouteEntry>,
+	arp_table: BTreeMap<Ipv4Address, MacAddress>,
+	pending_arp_requests: Vec<PendingArpRequest>,
+}
+
+/// Routing table entry
+#[derive(Debug, Clone)]
+pub struct RouteEntry {
+	pub destination: Ipv4Address,
+	pub netmask: Ipv4Address,
+	pub gateway: Option<Ipv4Address>,
+	pub interface: String,
+	pub metric: u32,
+}
+
+impl NetworkStack {
+	const fn new() -> Self {
+		Self {
+			interfaces: BTreeMap::new(),
+			interface_stats: BTreeMap::new(),
+			routing_table: Vec::new(),
+			arp_table: BTreeMap::new(),
+			pending_arp_requests: Vec::new(),
+		}
+	}
+
+	pub fn add_interface(&mut self, name: String, interface: Box<dyn NetworkInterface>) {
+		self.interface_stats
+			.insert(name.clone(), InterfaceStats::default());
+		self.interfaces.insert(name, interface);
+	}
+
+	pub fn remove_interface(&mut self, name: &str) -> Option<Box<dyn NetworkInterface>> {
+		self.interface_stats.remove(name);
+		self.interfaces.remove(name)
+	}
+
+	pub fn get_interface(&self, name: &str) -> Option<&dyn NetworkInterface> {
+		self.interfaces.get(name).map(|i| i.as_ref())
+	}
+
+	pub fn get_interface_mut<'a>(
+		&'a mut self,
+		name: &str,
+	) -> Option<&'a mut (dyn NetworkInterface + 'a)> {
+		if let Some(interface) = self.interfaces.get_mut(name) {
+			Some(interface.as_mut())
+		} else {
+			None
+		}
+	}
+
+	pub fn list_interfaces(&self) -> Vec<String> {
+		self.interfaces.keys().cloned().collect()
+	}
+
+	pub fn add_route(&mut self, route: RouteEntry) {
+		self.routing_table.push(route);
+		// Sort by metric (lower is better)
+		self.routing_table.sort_by_key(|r| r.metric);
+	}
+
+	pub fn find_route(&self, dest: Ipv4Address) -> Option<&RouteEntry> {
+		for route in &self.routing_table {
+			let dest_u32 = dest.to_u32();
+			let route_dest = route.destination.to_u32();
+			let netmask = route.netmask.to_u32();
+
+			if (dest_u32 & netmask) == (route_dest & netmask) {
+				return Some(route);
+			}
+		}
+		None
+	}
+
+	pub fn add_arp_entry(&mut self, ip: Ipv4Address, mac: MacAddress) {
+		self.arp_table.insert(ip, mac);
+	}
+
+	pub fn lookup_arp(&self, ip: Ipv4Address) -> Option<MacAddress> {
+		self.arp_table.get(&ip).copied()
+	}
+
+	pub fn send_packet(
+		&mut self,
+		dest: Ipv4Address,
+		data: &[u8],
+		protocol: ProtocolType,
+	) -> Result<()> {
+		// Clean up timed out ARP requests
+		let now = crate::time::get_time_ns();
+		self.pending_arp_requests
+			.retain(|req| now - req.timestamp < 10_000_000_000); // 10 seconds
+
+		// Find route (borrow self immutably)
+		let route = {
+			let route = self.find_route(dest).ok_or(Error::NetworkUnreachable)?;
+			route.clone() // Clone to avoid borrowing issues
+		};
+
+		// Look up MAC address first (borrow self immutably)
+		let dest_mac = if let Some(gateway) = route.gateway {
+			self.lookup_arp(gateway)
+		} else {
+			self.lookup_arp(dest)
+		};
+
+		let dest_mac = if let Some(mac) = dest_mac {
+			mac
+		} else {
+			// ARP lookup failed, send an ARP request and queue the packet
+			let interface = self
+				.get_interface(&route.interface)
+				.ok_or(Error::DeviceNotFound)?;
+			let arp_request = crate::arp::ArpPacket::new(
+				crate::arp::ArpOperation::Request,
+				interface.mac_address(),
+				interface.ip_address().unwrap_or(Ipv4Address::any()),
+				MacAddress::zero(),
+				dest,
+			);
+			let mut buffer = NetworkBuffer::new(28);
+			buffer.set_protocol(ProtocolType::ARP);
+			buffer.set_mac_addresses(interface.mac_address(), MacAddress::broadcast());
+			buffer.extend_from_slice(&arp_request.to_bytes())?;
+			let interface_mut = self
+				.get_interface_mut(&route.interface)
+				.ok_or(Error::DeviceNotFound)?;
+			interface_mut.send_packet(&buffer)?;
+
+			// Queue the original packet
+			let mut packet_to_queue = NetworkBuffer::new(data.len());
+			packet_to_queue.extend_from_slice(data)?;
+			packet_to_queue.set_protocol(protocol);
+			packet_to_queue.set_ip_addresses(Ipv4Address::any(), dest); // TODO: Set source IP
+			self.pending_arp_requests.push(PendingArpRequest {
+				packet: packet_to_queue,
+				ip: dest,
+				timestamp: crate::time::get_time_ns(),
+			});
+
+			return Ok(()); // We'll have to wait for the reply
+		};
+
+		// Get interface MAC address
+		let interface_mac = {
+			let interface = self
+				.get_interface(&route.interface)
+				.ok_or(Error::DeviceNotFound)?;
+			interface.mac_address()
+		};
+
+		// Build packet
+		let mut buffer = NetworkBuffer::new(1500);
+		buffer.set_protocol(protocol);
+		buffer.set_mac_addresses(interface_mac, dest_mac);
+		buffer.extend_from_slice(data)?;
+
+		// Send packet (borrow self mutably)
+		{
+			let interface = self
+				.get_interface_mut(&route.interface)
+				.ok_or(Error::DeviceNotFound)?;
+			interface.send_packet(&buffer)?;
+		}
+
+		// Update statistics
+		if let Some(stats) = self.interface_stats.get_mut(&route.interface) {
+			stats.packets_sent += 1;
+			stats.bytes_sent += buffer.len() as u64;
+		}
+
+		Ok(())
+	}
+
+	pub fn receive_and_handle_packets(&mut self) -> Result<Vec<NetworkBuffer>> {
+		let mut received_packets = Vec::new();
+		let mut unhandled_packets = Vec::new();
+
+		// First, receive all packets from all interfaces
+		for (name, interface) in &mut self.interfaces {
+			while let Some(packet) = interface.receive_packet()? {
+				if let Some(stats) = self.interface_stats.get_mut(name) {
+					stats.packets_received += 1;
+					stats.bytes_received += packet.len() as u64;
+				}
+				received_packets.push((name.clone(), packet));
+			}
+		}
+
+		// Now, process the received packets
+		for (interface_name, packet) in received_packets {
+			if packet.protocol == ProtocolType::ARP {
+				if let Ok(arp_packet) =
+					crate::arp::ArpPacket::from_bytes(packet.data())
+				{
+					self.handle_arp_packet(&arp_packet, &interface_name)?;
+				}
+			} else if packet.protocol == ProtocolType::ICMP {
+				if let Some(source_ip) = packet.source_ip {
+					self.handle_icmp_packet(source_ip, packet.data())?;
+				}
+			} else {
+				unhandled_packets.push(packet);
+			}
+		}
+
+		Ok(unhandled_packets)
+	}
+
+	pub fn receive_packets(&mut self) -> Result<Vec<NetworkBuffer>> {
+		self.receive_and_handle_packets()
+	}
+
+	pub fn get_interface_stats(&self, name: &str) -> Option<&InterfaceStats> {
+		self.interface_stats.get(name)
+	}
+
+	fn handle_arp_packet(
+		&mut self,
+		packet: &crate::arp::ArpPacket,
+		interface_name: &str,
+	) -> Result<()> {
+		// Add the sender to the ARP table
+		self.add_arp_entry(packet.spa, packet.sha);
+
+		// If it's a request for us, send a reply
+		if u16::from_be_bytes(packet.oper) == crate::arp::ArpOperation::Request as u16 {
+			if let Some(interface) = self.get_interface(interface_name) {
+				if let Some(ip_addr) = interface.ip_address() {
+					if ip_addr == packet.tpa {
+						let reply = crate::arp::ArpPacket::new(
+							crate::arp::ArpOperation::Reply,
+							interface.mac_address(),
+							ip_addr,
+							packet.sha,
+							packet.spa,
+						);
+						let mut buffer = NetworkBuffer::new(28);
+						buffer.set_protocol(ProtocolType::ARP);
+						buffer.set_mac_addresses(
+							interface.mac_address(),
+							packet.sha,
+						);
+						buffer.extend_from_slice(&reply.to_bytes())?;
+						if let Some(interface) =
+							self.get_interface_mut(interface_name)
+						{
+							interface.send_packet(&buffer)?;
+						}
+					}
+				}
+			}
+		}
+
+		// Check for pending packets
+		let mut packets_to_send = Vec::new();
+		let mut still_pending = Vec::new();
+		for pending in self.pending_arp_requests.drain(..) {
+			if pending.ip == packet.spa {
+				packets_to_send.push(pending);
+			} else {
+				still_pending.push(pending);
+			}
+		}
+		self.pending_arp_requests = still_pending;
+
+		for pending in packets_to_send {
+			self.send_packet(
+				pending.ip,
+				pending.packet.data(),
+				pending.packet.protocol,
+			)?;
+		}
+
+		Ok(())
+	}
+
+	fn handle_icmp_packet(&mut self, source_ip: Ipv4Address, packet: &[u8]) -> Result<()> {
+		if packet.len() < 8 {
+			return Err(Error::InvalidArgument);
+		}
+		let icmp_type = packet[0];
+		if icmp_type == crate::icmp::IcmpType::EchoRequest as u8 {
+			let mut reply = packet.to_vec();
+			reply[0] = crate::icmp::IcmpType::EchoReply as u8;
+			// Recalculate checksum
+			let checksum = utils::calculate_checksum(&reply);
+			reply[2] = (checksum >> 8) as u8;
+			reply[3] = (checksum & 0xFF) as u8;
+
+			self.send_packet(source_ip, &reply, ProtocolType::ICMP)?;
+		}
+		Ok(())
+	}
+}
+
+/// Global network stack
+pub static NETWORK_STACK: Spinlock<Option<NetworkStack>> = Spinlock::new(None);
+
+/// Initialize network stack
+pub fn init() -> Result<()> {
+	let mut stack = NETWORK_STACK.lock();
+	let mut network_stack = NetworkStack::new();
+
+	// Add loopback interface
+	let loopback = LoopbackInterface::new();
+	network_stack.add_interface("lo".to_string(), Box::new(loopback));
+
+	// Add route for loopback
+	network_stack.add_route(RouteEntry {
+		destination: Ipv4Address::new(127, 0, 0, 0),
+		netmask: Ipv4Address::new(255, 0, 0, 0),
+		gateway: None,
+		interface: "lo".to_string(),
+		metric: 0,
+	});
+
+	// Add ARP entry for loopback
+	network_stack.add_arp_entry(Ipv4Address::localhost(), MacAddress::zero());
+
+	*stack = Some(network_stack);
+	crate::info!("Network stack initialized");
+	Ok(())
+}
+
+/// Add a network interface
+pub fn add_network_interface(name: String, interface: Box<dyn NetworkInterface>) -> Result<()> {
+	let mut stack_opt = NETWORK_STACK.lock();
+	if let Some(ref mut stack) = *stack_opt {
+		stack.add_interface(name, interface);
+		Ok(())
+	} else {
+		Err(Error::NotInitialized)
+	}
+}
+
+pub mod utils {
+	/// Calculate checksum
+	pub fn calculate_checksum(data: &[u8]) -> u16 {
+		let mut sum = 0u32;
+
+		// Sum all 16-bit words
+		for chunk in data.chunks(2) {
+			if chunk.len() == 2 {
+				sum += ((chunk[0] as u32) << 8) + (chunk[1] as u32);
+			} else {
+				sum += (chunk[0] as u32) << 8;
+			}
+		}
+
+		// Add carry
+		while sum >> 16 != 0 {
+			sum = (sum & 0xFFFF) + (sum >> 16);
+		}
+
+		// One's complement
+		!sum as u16
+	}
+}
+
+/// Send a packet
+pub fn send_packet(dest: Ipv4Address, data: &[u8], protocol: ProtocolType) -> Result<()> {
+	let mut stack_opt = NETWORK_STACK.lock();
+	if let Some(ref mut stack) = *stack_opt {
+		stack.send_packet(dest, data, protocol)
+	} else {
+		Err(Error::NotInitialized)
+	}
+}
+
+/// Add a route
+pub fn add_route(
+	destination: Ipv4Address,
+	netmask: Ipv4Address,
+	gateway: Option<Ipv4Address>,
+	interface: String,
+	metric: u32,
+) -> Result<()> {
+	let mut stack_opt = NETWORK_STACK.lock();
+	if let Some(ref mut stack) = *stack_opt {
+		stack.add_route(RouteEntry {
+			destination,
+			netmask,
+			gateway,
+			interface,
+			metric,
+		});
+		Ok(())
+	} else {
+		Err(Error::NotInitialized)
+	}
+}
+
+/// Add an ARP entry
+pub fn add_arp_entry(ip: Ipv4Address, mac: MacAddress) -> Result<()> {
+	let mut stack_opt = NETWORK_STACK.lock();
+	if let Some(ref mut stack) = *stack_opt {
+		stack.add_arp_entry(ip, mac);
+		Ok(())
+	} else {
+		Err(Error::NotInitialized)
+	}
+}

kernel/src/panic.rs

@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel panic handler
+
+use core::fmt::Write;
+use core::panic::PanicInfo;
+
+/// Panic handler
+#[panic_handler]
+pub fn panic_handler(info: &PanicInfo) -> ! {
+	// Disable interrupts
+	#[cfg(target_arch = "x86_64")]
+	unsafe {
+		core::arch::asm!("cli");
+	}
+
+	// Print panic information
+	let mut writer = PanicWriter;
+	writeln!(writer, "\n\n=== KERNEL PANIC ===").ok();
+
+	if let Some(location) = info.location() {
+		writeln!(
+			writer,
+			"Panic at {}:{}:{}",
+			location.file(),
+			location.line(),
+			location.column()
+		)
+		.ok();
+	}
+
+	let message = info.message();
+	writeln!(writer, "Message: {}", message).ok();
+
+	writeln!(writer, "===================\n").ok();
+
+	// Print stack trace
+	print_stack_trace(&mut writer);
+
+	// Save panic information to system log
+	save_panic_info(info);
+
+	// Halt the system
+	loop {
+		#[cfg(target_arch = "x86_64")]
+		unsafe {
+			core::arch::asm!("hlt");
+		}
+
+		#[cfg(not(target_arch = "x86_64"))]
+		core::hint::spin_loop();
+	}
+}
+
+/// Print a simple stack trace
+fn print_stack_trace<W: core::fmt::Write>(writer: &mut W) {
+	writeln!(writer, "Stack trace:").ok();
+
+	// Get current frame pointer
+	let mut rbp: *const usize;
+	unsafe {
+		core::arch::asm!("mov {}, rbp", out(reg) rbp);
+	}
+
+	// Walk the stack (simplified)
+	let mut frame_count = 0;
+	while !rbp.is_null() && frame_count < 10 {
+		unsafe {
+			// Read return address from stack frame
+			let ret_addr = rbp.add(1).read_volatile();
+			writeln!(writer, "  #{}: 0x{:016x}", frame_count, ret_addr).ok();
+
+			// Move to previous frame
+			rbp = rbp.read_volatile() as *const usize;
+			frame_count += 1;
+
+			// Safety check to avoid infinite loops
+			if (rbp as usize) < 0x1000 || (rbp as usize) > 0x7FFFFFFFFFFF {
+				break;
+			}
+		}
+	}
+}
+
+/// Save panic information to system log
+fn save_panic_info(info: &core::panic::PanicInfo) {
+	// In a real implementation, this would write to a persistent log
+	// For now, we'll just store it in memory for potential retrieval
+
+	if let Some(location) = info.location() {
+		crate::info!(
+			"PANIC LOGGED: {}:{}:{} - {}",
+			location.file(),
+			location.line(),
+			location.column(),
+			info.message()
+		);
+	} else {
+		crate::info!("PANIC LOGGED: {}", info.message());
+	}
+}
+
+/// Writer for panic messages
+struct PanicWriter;
+
+impl Write for PanicWriter {
+	fn write_str(&mut self, s: &str) -> core::fmt::Result {
+		// Write directly to VGA buffer or serial port
+		for byte in s.bytes() {
+			#[cfg(target_arch = "x86_64")]
+			unsafe {
+				// Write to serial port (COM1)
+				core::arch::asm!(
+				    "out dx, al",
+				    in("dx") 0x3f8u16,
+				    in("al") byte,
+				);
+			}
+		}
+		Ok(())
+	}
+}

kernel/src/perf.rs

@@ -0,0 +1,317 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Performance monitoring and profiling
+
+use alloc::{collections::BTreeMap, format, string::String, vec::Vec};
+use core::sync::atomic::{AtomicU64, Ordering};
+
+use crate::error::Result;
+use crate::sync::Spinlock;
+use crate::types::Jiffies;
+
+/// Performance counter types
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub enum CounterType {
+	CpuCycles,
+	Instructions,
+	CacheMisses,
+	BranchMisses,
+	PageFaults,
+	ContextSwitches,
+	Interrupts,
+	SystemCalls,
+	MemoryAllocations,
+	FileOperations,
+	NetworkPackets,
+	Custom(u32),
+}
+
+/// Performance event
+#[derive(Debug, Clone)]
+pub struct PerfEvent {
+	pub counter_type: CounterType,
+	pub count: u64,
+	pub timestamp: Jiffies,
+	pub pid: Option<u32>,
+	pub cpu: Option<u32>,
+}
+
+/// Performance counter
+#[derive(Debug)]
+pub struct PerfCounter {
+	pub counter_type: CounterType,
+	pub value: AtomicU64,
+	pub enabled: bool,
+	pub description: String,
+}
+
+impl PerfCounter {
+	pub fn new(counter_type: CounterType, description: String) -> Self {
+		Self {
+			counter_type,
+			value: AtomicU64::new(0),
+			enabled: true,
+			description,
+		}
+	}
+
+	pub fn increment(&self) {
+		if self.enabled {
+			self.value.fetch_add(1, Ordering::Relaxed);
+		}
+	}
+
+	pub fn add(&self, value: u64) {
+		if self.enabled {
+			self.value.fetch_add(value, Ordering::Relaxed);
+		}
+	}
+
+	pub fn get(&self) -> u64 {
+		self.value.load(Ordering::Relaxed)
+	}
+
+	pub fn reset(&self) {
+		self.value.store(0, Ordering::Relaxed);
+	}
+
+	pub fn enable(&mut self) {
+		self.enabled = true;
+	}
+
+	pub fn disable(&mut self) {
+		self.enabled = false;
+	}
+}
+
+/// Performance monitoring subsystem
+pub struct PerfMonitor {
+	counters: BTreeMap<CounterType, PerfCounter>,
+	events: Vec<PerfEvent>,
+	max_events: usize,
+}
+
+impl PerfMonitor {
+	pub const fn new() -> Self {
+		Self {
+			counters: BTreeMap::new(),
+			events: Vec::new(),
+			max_events: 10000,
+		}
+	}
+
+	pub fn init(&mut self) {
+		// Initialize standard counters
+		self.add_counter(CounterType::CpuCycles, "CPU cycles executed".into());
+		self.add_counter(CounterType::Instructions, "Instructions executed".into());
+		self.add_counter(CounterType::CacheMisses, "Cache misses".into());
+		self.add_counter(CounterType::BranchMisses, "Branch prediction misses".into());
+		self.add_counter(CounterType::PageFaults, "Page faults".into());
+		self.add_counter(CounterType::ContextSwitches, "Context switches".into());
+		self.add_counter(CounterType::Interrupts, "Interrupts handled".into());
+		self.add_counter(CounterType::SystemCalls, "System calls".into());
+		self.add_counter(CounterType::MemoryAllocations, "Memory allocations".into());
+		self.add_counter(CounterType::FileOperations, "File operations".into());
+		self.add_counter(CounterType::NetworkPackets, "Network packets".into());
+	}
+
+	pub fn add_counter(&mut self, counter_type: CounterType, description: String) {
+		let counter = PerfCounter::new(counter_type, description);
+		self.counters.insert(counter_type, counter);
+	}
+
+	pub fn increment_counter(&self, counter_type: CounterType) {
+		if let Some(counter) = self.counters.get(&counter_type) {
+			counter.increment();
+		}
+	}
+
+	pub fn add_to_counter(&self, counter_type: CounterType, value: u64) {
+		if let Some(counter) = self.counters.get(&counter_type) {
+			counter.add(value);
+		}
+	}
+
+	pub fn get_counter(&self, counter_type: CounterType) -> Option<u64> {
+		self.counters.get(&counter_type).map(|c| c.get())
+	}
+
+	pub fn reset_counter(&self, counter_type: CounterType) {
+		if let Some(counter) = self.counters.get(&counter_type) {
+			counter.reset();
+		}
+	}
+
+	pub fn record_event(&mut self, event: PerfEvent) {
+		if self.events.len() >= self.max_events {
+			self.events.remove(0); // Remove oldest event
+		}
+		self.events.push(event);
+	}
+
+	pub fn get_events(&self) -> &[PerfEvent] {
+		&self.events
+	}
+
+	pub fn clear_events(&mut self) {
+		self.events.clear();
+	}
+
+	pub fn get_counters(&self) -> &BTreeMap<CounterType, PerfCounter> {
+		&self.counters
+	}
+
+	pub fn generate_report(&self) -> String {
+		let mut report = String::from("Performance Monitor Report\n");
+		report.push_str("==========================\n\n");
+
+		for (counter_type, counter) in &self.counters {
+			report.push_str(&format!(
+				"{:?}: {} ({})\n",
+				counter_type,
+				counter.get(),
+				counter.description
+			));
+		}
+
+		report.push_str(&format!("\nTotal events recorded: {}\n", self.events.len()));
+
+		if !self.events.is_empty() {
+			report.push_str("\nRecent events:\n");
+			for event in self.events.iter().rev().take(10) {
+				report.push_str(&format!(
+					"  {:?}: {} at {:?}\n",
+					event.counter_type, event.count, event.timestamp
+				));
+			}
+		}
+
+		report
+	}
+}
+
+/// Global performance monitor
+static PERF_MONITOR: Spinlock<Option<PerfMonitor>> = Spinlock::new(None);
+
+/// Initialize performance monitoring
+pub fn init_perf_monitor() -> Result<()> {
+	let mut monitor = PERF_MONITOR.lock();
+	*monitor = Some(PerfMonitor::new());
+	if let Some(ref mut m) = *monitor {
+		m.init();
+	}
+	crate::info!("Performance monitoring initialized");
+	Ok(())
+}
+
+/// Increment a performance counter
+pub fn perf_counter_inc(counter_type: CounterType) {
+	let monitor = PERF_MONITOR.lock();
+	if let Some(ref m) = *monitor {
+		m.increment_counter(counter_type);
+	}
+}
+
+/// Add to a performance counter
+pub fn perf_counter_add(counter_type: CounterType, value: u64) {
+	let monitor = PERF_MONITOR.lock();
+	if let Some(ref m) = *monitor {
+		m.add_to_counter(counter_type, value);
+	}
+}
+
+/// Get performance counter value
+pub fn perf_counter_get(counter_type: CounterType) -> Option<u64> {
+	let monitor = PERF_MONITOR.lock();
+	if let Some(ref m) = *monitor {
+		m.get_counter(counter_type)
+	} else {
+		None
+	}
+}
+
+/// Reset performance counter
+pub fn perf_counter_reset(counter_type: CounterType) {
+	let monitor = PERF_MONITOR.lock();
+	if let Some(ref m) = *monitor {
+		m.reset_counter(counter_type);
+	}
+}
+
+/// Record performance event
+pub fn perf_event_record(counter_type: CounterType, count: u64) {
+	let mut monitor = PERF_MONITOR.lock();
+	if let Some(ref mut m) = *monitor {
+		let event = PerfEvent {
+			counter_type,
+			count,
+			timestamp: crate::time::get_jiffies(),
+			pid: crate::process::current_process_pid().map(|p| p.0),
+			cpu: Some(0), // TODO: Get current CPU ID
+		};
+		m.record_event(event);
+	}
+}
+
+/// Generate performance report
+pub fn perf_generate_report() -> String {
+	let monitor = PERF_MONITOR.lock();
+	if let Some(ref m) = *monitor {
+		m.generate_report()
+	} else {
+		"Performance monitoring not initialized".into()
+	}
+}
+
+/// Clear performance events
+pub fn perf_clear_events() {
+	let mut monitor = PERF_MONITOR.lock();
+	if let Some(ref mut m) = *monitor {
+		m.clear_events();
+	}
+}
+
+/// Performance measurement macro
+#[macro_export]
+macro_rules! perf_measure {
+	($counter_type:expr, $code:block) => {{
+		let start = crate::time::get_jiffies();
+		let result = $code;
+		let end = crate::time::get_jiffies();
+		crate::perf::perf_counter_add($counter_type, (end - start).as_u64());
+		result
+	}};
+}
+
+/// Convenience functions for common performance counters
+pub mod counters {
+	use super::*;
+
+	pub fn inc_page_faults() {
+		perf_counter_inc(CounterType::PageFaults);
+	}
+
+	pub fn inc_context_switches() {
+		perf_counter_inc(CounterType::ContextSwitches);
+	}
+
+	pub fn inc_interrupts() {
+		perf_counter_inc(CounterType::Interrupts);
+	}
+
+	pub fn inc_syscalls() {
+		perf_counter_inc(CounterType::SystemCalls);
+	}
+
+	pub fn inc_memory_allocs() {
+		perf_counter_inc(CounterType::MemoryAllocations);
+	}
+
+	pub fn inc_file_ops() {
+		perf_counter_inc(CounterType::FileOperations);
+	}
+
+	pub fn inc_network_packets() {
+		perf_counter_inc(CounterType::NetworkPackets);
+	}
+}

kernel/src/prelude.rs

@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel prelude - commonly used types and traits
+
+// Re-export macros
+pub use alloc::vec;
+// Re-export common alloc types
+pub use alloc::{
+	boxed::Box,
+	collections::{BTreeMap, BTreeSet},
+	format,
+	string::{String, ToString},
+	vec::Vec,
+};
+// Re-export core types
+pub use core::{
+	fmt, mem,
+	option::Option::{self, None, Some},
+	ptr,
+	result::Result as CoreResult,
+	slice, str,
+};
+
+pub use crate::device::Device;
+pub use crate::driver::{BlockDriverOps, CharDriverOps, Driver};
+pub use crate::error::{Error, Result};
+pub use crate::memory::{PageTable, PhysAddr, UserPtr, UserSlicePtr, VirtAddr};
+pub use crate::process::{Process, Thread};
+pub use crate::sync::{Mutex, RwLock, Spinlock};
+pub use crate::task::Task;
+pub use crate::types::*;
+
+/// Print macros for kernel logging
+#[macro_export]
+macro_rules! print {
+    ($($arg:tt)*) => ($crate::console::_print(format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! println {
+    () => ($crate::print!("\n"));
+    ($($arg:tt)*) => ($crate::print!("{}\n", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! kprint {
+    ($($arg:tt)*) => ($crate::console::_kprint(format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! kprintln {
+    () => ($crate::kprint!("\n"));
+    ($($arg:tt)*) => ($crate::kprint!("[KERNEL] {}\n", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! debug {
+    ($($arg:tt)*) => {
+        #[cfg(feature = "debug")]
+        $crate::kprintln!("[DEBUG] {}", format_args!($($arg)*))
+    };
+}
+
+#[macro_export]
+macro_rules! info {
+    ($($arg:tt)*) => ($crate::kprintln!("[INFO] {}", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! warn {
+    ($($arg:tt)*) => ($crate::kprintln!("[WARN] {}", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! error {
+    ($($arg:tt)*) => ($crate::kprintln!("[ERROR] {}", format_args!($($arg)*)));
+}
+
+/// Module definition macro
+#[macro_export]
+macro_rules! module {
+	(
+		type:
+		$type:ty,name:
+		$name:expr,author:
+		$author:expr,description:
+		$description:expr,license:
+		$license:expr $(,)?
+	) => {
+		static __THIS_MODULE: $crate::module::ThisModule = $crate::module::ThisModule {
+			name: $name,
+			author: $author,
+			description: $description,
+			license: $license,
+		};
+
+		#[no_mangle]
+		pub extern "C" fn init_module() -> core::ffi::c_int {
+			match <$type as $crate::module::Module>::init(&__THIS_MODULE) {
+				Ok(_) => 0,
+				Err(e) => e.to_errno(),
+			}
+		}
+
+		#[no_mangle]
+		pub extern "C" fn cleanup_module() {
+			<$type as $crate::module::Module>::exit(&__THIS_MODULE)
+		}
+	};
+}

kernel/src/process.rs

@@ -0,0 +1,378 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Process and thread management
+
+use alloc::{
+	collections::BTreeMap,
+	string::{String, ToString},
+	vec::Vec,
+};
+use core::sync::atomic::{AtomicU32, Ordering};
+
+use crate::arch::x86_64::context::Context;
+use crate::error::{Error, Result};
+use crate::memory::VirtAddr;
+use crate::sync::Spinlock;
+use crate::types::{Gid, Pid, Tid, Uid};
+
+/// Process state - compatible with Linux kernel
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ProcessState {
+	Running,
+	Sleeping,
+	Stopped,
+	Zombie,
+	Dead,
+}
+
+/// Process structure - similar to Linux task_struct
+#[derive(Debug, Clone)]
+pub struct Process {
+	pub pid: Pid,
+	pub parent: Option<Pid>,
+	pub state: ProcessState,
+	pub uid: Uid,
+	pub gid: Gid,
+	pub name: String,
+	pub threads: Vec<Thread>,
+	pub memory_map: Option<VirtAddr>, // Points to mm_struct equivalent
+	pub files: Vec<u32>,              // File descriptor table
+	pub signal_pending: bool,
+	pub exit_code: i32,
+}
+
+impl Process {
+	pub fn new(pid: Pid, name: String, uid: Uid, gid: Gid) -> Self {
+		Self {
+			pid,
+			parent: None,
+			state: ProcessState::Running,
+			uid,
+			gid,
+			name,
+			threads: Vec::new(),
+			memory_map: None,
+			files: Vec::new(),
+			signal_pending: false,
+			exit_code: 0,
+		}
+	}
+
+	/// Add a thread to this process
+	pub fn add_thread(&mut self, thread: Thread) {
+		self.threads.push(thread);
+	}
+
+	/// Get the main thread
+	pub fn main_thread(&self) -> Option<&Thread> {
+		self.threads.first()
+	}
+
+	/// Set process state
+	pub fn set_state(&mut self, state: ProcessState) {
+		self.state = state;
+	}
+
+	/// Check if process is running
+	pub fn is_running(&self) -> bool {
+		self.state == ProcessState::Running
+	}
+
+	/// Fork the current process (create a copy)
+	pub fn fork(&self) -> Result<Process> {
+		let new_pid = allocate_pid();
+		let mut child = self.clone();
+		child.pid = new_pid;
+		child.parent = Some(self.pid);
+		child.state = ProcessState::Running;
+
+		// TODO: Copy memory space (copy-on-write)
+		// TODO: Copy file descriptor table
+		// TODO: Set up new page tables
+
+		Ok(child)
+	}
+
+	/// Execute a new program in this process
+	pub fn exec(&mut self, program_path: &str, args: Vec<String>) -> Result<()> {
+		// TODO: Load program from filesystem
+		// TODO: Set up new memory layout
+		// TODO: Initialize stack with arguments
+		// TODO: Set entry point
+
+		self.name = program_path.to_string();
+		Ok(())
+	}
+
+	/// Terminate the process with given exit code
+	pub fn exit(&mut self, exit_code: i32) {
+		self.state = ProcessState::Zombie;
+		self.exit_code = exit_code;
+
+		// TODO: Free memory
+		// TODO: Close file descriptors
+		// TODO: Notify parent
+		// TODO: Reparent children to init
+	}
+
+	/// Send a signal to the process
+	pub fn send_signal(&mut self, signal: i32) -> Result<()> {
+		match signal {
+			9 => {
+				// SIGKILL
+				self.state = ProcessState::Dead;
+			}
+			15 => {
+				// SIGTERM
+				self.signal_pending = true;
+				// TODO: Add to signal queue
+			}
+			_ => {
+				// TODO: Handle other signals
+			}
+		}
+		Ok(())
+	}
+
+	/// Wait for child processes
+	pub fn wait(&self) -> Result<(Pid, i32)> {
+		// TODO: Block until child exits
+		// TODO: Return child PID and exit status
+		Err(Error::ECHILD)
+	}
+}
+
+/// Thread structure - Linux-compatible
+#[derive(Debug, Clone)]
+pub struct Thread {
+	pub tid: Tid,
+	pub process_pid: Pid,
+	pub state: ProcessState,
+	pub stack_pointer: VirtAddr,
+	pub instruction_pointer: VirtAddr,
+	pub priority: i32,
+	pub nice: i32,     // Nice value (-20 to 19)
+	pub cpu_time: u64, // Nanoseconds
+	pub context: Context,
+}
+
+impl Thread {
+	pub fn new(tid: Tid, process_pid: Pid, priority: i32) -> Self {
+		Self {
+			tid,
+			process_pid,
+			state: ProcessState::Running,
+			stack_pointer: VirtAddr::new(0),
+			instruction_pointer: VirtAddr::new(0),
+			priority,
+			nice: 0,
+			cpu_time: 0,
+			context: Context::new(),
+		}
+	}
+
+	/// Set thread state
+	pub fn set_state(&mut self, state: ProcessState) {
+		self.state = state;
+	}
+
+	/// Update CPU time
+	pub fn add_cpu_time(&mut self, time: u64) {
+		self.cpu_time += time;
+	}
+}
+
+/// Global process table
+pub static PROCESS_TABLE: Spinlock<ProcessTable> = Spinlock::new(ProcessTable::new());
+static NEXT_PID: AtomicU32 = AtomicU32::new(1);
+static NEXT_TID: AtomicU32 = AtomicU32::new(1);
+
+/// Process table implementation
+pub struct ProcessTable {
+	processes: BTreeMap<Pid, Process>,
+	current_process: Option<Pid>,
+}
+
+impl ProcessTable {
+	const fn new() -> Self {
+		Self {
+			processes: BTreeMap::new(),
+			current_process: None,
+		}
+	}
+
+	pub fn add_process(&mut self, process: Process) {
+		let pid = process.pid;
+		self.processes.insert(pid, process);
+		if self.current_process.is_none() {
+			self.current_process = Some(pid);
+		}
+	}
+
+	fn get_process(&self, pid: Pid) -> Option<&Process> {
+		self.processes.get(&pid)
+	}
+
+	fn get_process_mut(&mut self, pid: Pid) -> Option<&mut Process> {
+		self.processes.get_mut(&pid)
+	}
+
+	#[allow(dead_code)]
+	fn remove_process(&mut self, pid: Pid) -> Option<Process> {
+		let process = self.processes.remove(&pid);
+		if self.current_process == Some(pid) {
+			self.current_process = self.processes.keys().next().copied();
+		}
+		process
+	}
+
+	fn list_processes(&self) -> Vec<Pid> {
+		self.processes.keys().copied().collect()
+	}
+
+	pub fn find_thread(&self, tid: Tid) -> Option<&Thread> {
+		for process in self.processes.values() {
+			for thread in &process.threads {
+				if thread.tid == tid {
+					return Some(thread);
+				}
+			}
+		}
+		None
+	}
+
+	pub fn find_thread_mut(&mut self, tid: Tid) -> Option<&mut Thread> {
+		for process in self.processes.values_mut() {
+			for thread in &mut process.threads {
+				if thread.tid == tid {
+					return Some(thread);
+				}
+			}
+		}
+		None
+	}
+
+	pub fn find_two_threads_mut(
+		&mut self,
+		tid1: Tid,
+		tid2: Tid,
+	) -> (Option<&mut Thread>, Option<&mut Thread>) {
+		if tid1 == tid2 {
+			let t = self.find_thread_mut(tid1);
+			return (t, None);
+		}
+
+		// This is a bit inefficient but safe
+		// We can't easily return two mutable references to the same structure
+		// But since they are in different processes or different threads, they are distinct memory locations.
+		// We can use unsafe to cheat the borrow checker, knowing that tid1 != tid2.
+
+		let ptr = self as *mut ProcessTable;
+		unsafe {
+			let t1 = (*ptr).find_thread_mut(tid1);
+			let t2 = (*ptr).find_thread_mut(tid2);
+			(t1, t2)
+		}
+	}
+}
+
+/// Allocate a new PID
+pub fn allocate_pid() -> Pid {
+	Pid(NEXT_PID.fetch_add(1, Ordering::SeqCst))
+}
+
+/// Allocate a new TID
+pub fn allocate_tid() -> Tid {
+	Tid(NEXT_TID.fetch_add(1, Ordering::SeqCst))
+}
+
+/// Create a new process
+pub fn create_process(name: String, uid: Uid, gid: Gid) -> Result<Pid> {
+	let pid = allocate_pid();
+	let mut process = Process::new(pid, name, uid, gid);
+
+	// Create main thread
+	let tid = allocate_tid();
+	let main_thread = Thread::new(tid, pid, 0);
+	process.add_thread(main_thread);
+
+	let mut table = PROCESS_TABLE.lock();
+	table.add_process(process);
+
+	Ok(pid)
+}
+
+/// Add a thread to the kernel process (PID 0)
+pub fn add_kernel_thread(tid: Tid, context: Context, stack_pointer: VirtAddr) -> Result<()> {
+	let mut table = PROCESS_TABLE.lock();
+	if let Some(process) = table.get_process_mut(Pid(0)) {
+		let mut thread = Thread::new(tid, Pid(0), 0);
+		thread.context = context;
+		thread.stack_pointer = stack_pointer;
+		process.add_thread(thread);
+		Ok(())
+	} else {
+		Err(Error::NotFound)
+	}
+}
+
+/// Get current process PID
+pub fn current_process_pid() -> Option<Pid> {
+	let table = PROCESS_TABLE.lock();
+	table.current_process
+}
+
+/// Get current process object
+pub fn current_process() -> Option<Process> {
+	let table = PROCESS_TABLE.lock();
+	if let Some(pid) = table.current_process {
+		table.get_process(pid).cloned()
+	} else {
+		None
+	}
+}
+
+/// Get process by PID
+pub fn find_process(pid: Pid) -> Option<Process> {
+	let table = PROCESS_TABLE.lock();
+	table.get_process(pid).cloned()
+}
+
+/// Kill a process
+pub fn kill_process(pid: Pid, signal: i32) -> Result<()> {
+	let mut table = PROCESS_TABLE.lock();
+	if let Some(process) = table.get_process_mut(pid) {
+		process.set_state(ProcessState::Dead);
+		process.exit_code = signal;
+		Ok(())
+	} else {
+		Err(Error::NotFound)
+	}
+}
+
+/// List all processes
+pub fn list_processes() -> Vec<Pid> {
+	let table = PROCESS_TABLE.lock();
+	table.list_processes()
+}
+
+/// Initialize process management
+pub fn init_process_management() -> Result<()> {
+	init()
+}
+
+/// Initialize the process subsystem
+pub fn init() -> Result<()> {
+	// Initialize the process table and create kernel process (PID 0)
+	let kernel_pid = create_process(
+		"kernel".to_string(),
+		Uid(0), // root
+		Gid(0), // root
+	)?;
+
+	crate::info!(
+		"Process management initialized with kernel PID {}",
+		kernel_pid.0
+	);
+	Ok(())
+}

kernel/src/scheduler.rs

@@ -0,0 +1,670 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Task scheduler compatible with Linux kernel CFS (Completely Fair Scheduler)
+
+use alloc::{
+	collections::{BTreeMap, VecDeque},
+	vec::Vec,
+};
+use core::sync::atomic::{AtomicU64, Ordering};
+
+use crate::arch::x86_64::context::{switch_context, Context};
+use crate::error::{Error, Result};
+use crate::process::{Thread, PROCESS_TABLE};
+use crate::sync::Spinlock;
+use crate::time;
+use crate::types::Tid;
+
+/// Scheduler policies - Linux compatible
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum SchedulerPolicy {
+	Normal = 0,     // SCHED_NORMAL
+	Fifo = 1,       // SCHED_FIFO
+	RoundRobin = 2, // SCHED_RR
+	Batch = 3,      // SCHED_BATCH
+	Idle = 5,       // SCHED_IDLE
+	Deadline = 6,   // SCHED_DEADLINE
+}
+
+/// Scheduler priority levels
+pub const MAX_PRIO: i32 = 140;
+pub const MAX_USER_RT_PRIO: i32 = 100;
+pub const MAX_RT_PRIO: i32 = MAX_USER_RT_PRIO;
+pub const DEFAULT_PRIO: i32 = MAX_RT_PRIO + 20;
+pub const MIN_NICE: i32 = -20;
+pub const MAX_NICE: i32 = 19;
+
+/// Convert nice value to priority
+pub fn nice_to_prio(nice: i32) -> i32 {
+	DEFAULT_PRIO + nice
+}
+
+/// Convert priority to nice value
+pub fn prio_to_nice(prio: i32) -> i32 {
+	prio - DEFAULT_PRIO
+}
+
+/// Scheduler entity - represents a schedulable unit
+#[derive(Debug, Clone)]
+pub struct SchedEntity {
+	pub tid: Tid,
+	pub policy: SchedulerPolicy,
+	pub priority: i32,
+	pub nice: i32,
+	pub vruntime: u64,         // Virtual runtime for CFS
+	pub exec_start: u64,       // Last execution start time
+	pub sum_exec_runtime: u64, // Total execution time
+	pub prev_sum_exec_runtime: u64,
+	pub load_weight: u32, // Load weight for this entity
+	pub runnable_weight: u32,
+	pub on_rq: bool, // On run queue?
+}
+
+impl SchedEntity {
+	pub fn new(tid: Tid, policy: SchedulerPolicy, nice: i32) -> Self {
+		let priority = nice_to_prio(nice);
+		Self {
+			tid,
+			policy,
+			priority,
+			nice,
+			vruntime: 0,
+			exec_start: 0,
+			sum_exec_runtime: 0,
+			prev_sum_exec_runtime: 0,
+			load_weight: nice_to_weight(nice),
+			runnable_weight: nice_to_weight(nice),
+			on_rq: false,
+		}
+	}
+
+	/// Update virtual runtime
+	pub fn update_vruntime(&mut self, delta: u64) {
+		// Virtual runtime is weighted by load
+		let weighted_delta = delta * 1024 / self.load_weight as u64;
+		self.vruntime += weighted_delta;
+	}
+}
+
+/// Convert nice value to load weight (Linux compatible)
+fn nice_to_weight(nice: i32) -> u32 {
+	// Linux nice-to-weight table (simplified)
+	match nice {
+		-20 => 88761,
+		-19 => 71755,
+		-18 => 56483,
+		-17 => 46273,
+		-16 => 36291,
+		-15 => 29154,
+		-14 => 23254,
+		-13 => 18705,
+		-12 => 14949,
+		-11 => 11916,
+		-10 => 9548,
+		-9 => 7620,
+		-8 => 6100,
+		-7 => 4904,
+		-6 => 3906,
+		-5 => 3121,
+		-4 => 2501,
+		-3 => 1991,
+		-2 => 1586,
+		-1 => 1277,
+		0 => 1024, // Default weight
+		1 => 820,
+		2 => 655,
+		3 => 526,
+		4 => 423,
+		5 => 335,
+		6 => 272,
+		7 => 215,
+		8 => 172,
+		9 => 137,
+		10 => 110,
+		11 => 87,
+		12 => 70,
+		13 => 56,
+		14 => 45,
+		15 => 36,
+		16 => 29,
+		17 => 23,
+		18 => 18,
+		19 => 15,
+		_ => 1024, // Default for out-of-range values
+	}
+}
+
+/// CFS (Completely Fair Scheduler) run queue
+#[derive(Debug)]
+pub struct CfsRunQueue {
+	tasks_timeline: BTreeMap<u64, SchedEntity>, // Red-black tree equivalent
+	min_vruntime: u64,
+	nr_running: u32,
+	load_weight: u64,
+	runnable_weight: u64,
+}
+
+impl CfsRunQueue {
+	pub fn new() -> Self {
+		Self {
+			tasks_timeline: BTreeMap::new(),
+			min_vruntime: 0,
+			nr_running: 0,
+			load_weight: 0,
+			runnable_weight: 0,
+		}
+	}
+
+	/// Add task to run queue
+	pub fn enqueue_task(&mut self, mut se: SchedEntity) {
+		// Place entity in timeline
+		if !se.on_rq {
+			se.on_rq = true;
+
+			// Ensure vruntime is not too far behind
+			if se.vruntime < self.min_vruntime {
+				se.vruntime = self.min_vruntime;
+			}
+
+			self.tasks_timeline.insert(se.vruntime, se.clone());
+			self.nr_running += 1;
+			self.load_weight += se.load_weight as u64;
+			self.runnable_weight += se.runnable_weight as u64;
+		}
+	}
+
+	/// Remove task from run queue
+	pub fn dequeue_task(&mut self, se: &SchedEntity) -> bool {
+		if se.on_rq {
+			self.tasks_timeline.remove(&se.vruntime);
+			self.nr_running -= 1;
+			self.load_weight -= se.load_weight as u64;
+			self.runnable_weight -= se.runnable_weight as u64;
+			true
+		} else {
+			false
+		}
+	}
+
+	/// Pick next task to run
+	pub fn pick_next_task(&mut self) -> Option<SchedEntity> {
+		// Pick leftmost task (smallest vruntime)
+		if let Some((vruntime, se)) = self.tasks_timeline.iter().next() {
+			let se = se.clone();
+			let vruntime = *vruntime;
+			self.tasks_timeline.remove(&vruntime);
+			self.nr_running -= 1;
+			self.load_weight -= se.load_weight as u64;
+			self.runnable_weight -= se.runnable_weight as u64;
+
+			// Update min_vruntime
+			if let Some((next_vruntime, _)) = self.tasks_timeline.iter().next() {
+				self.min_vruntime =
+					core::cmp::max(self.min_vruntime, *next_vruntime);
+			} else {
+				self.min_vruntime = se.vruntime;
+			}
+
+			Some(se)
+		} else {
+			None
+		}
+	}
+
+	/// Update minimum virtual runtime
+	pub fn update_min_vruntime(&mut self) {
+		if let Some((&next_vruntime, _)) = self.tasks_timeline.iter().next() {
+			self.min_vruntime = core::cmp::max(self.min_vruntime, next_vruntime);
+		}
+	}
+}
+
+/// Real-time run queue  
+#[derive(Debug)]
+pub struct RtRunQueue {
+	runqueue: VecDeque<SchedEntity>,
+	nr_running: u32,
+}
+
+impl RtRunQueue {
+	pub const fn new() -> Self {
+		Self {
+			runqueue: VecDeque::new(),
+			nr_running: 0,
+		}
+	}
+
+	pub fn enqueue_task(&mut self, se: SchedEntity) {
+		self.runqueue.push_back(se);
+		self.nr_running += 1;
+	}
+
+	pub fn dequeue_task(&mut self, se: &SchedEntity) -> bool {
+		if let Some(pos) = self.runqueue.iter().position(|task| task.tid == se.tid) {
+			self.nr_running -= 1;
+			self.runqueue.remove(pos);
+			true
+		} else {
+			false
+		}
+	}
+
+	pub fn pick_next_task(&mut self) -> Option<SchedEntity> {
+		if self.nr_running > 0 {
+			self.nr_running -= 1;
+			self.runqueue.pop_front()
+		} else {
+			None
+		}
+	}
+}
+
+/// Per-CPU run queue
+#[derive(Debug)]
+pub struct RunQueue {
+	pub cpu: u32,
+	pub nr_running: u32,
+	pub current: Option<SchedEntity>,
+	pub cfs: CfsRunQueue,
+	pub rt: RtRunQueue,
+	pub idle_task: Option<SchedEntity>,
+	pub clock: u64,
+	pub clock_task: u64,
+}
+
+impl RunQueue {
+	pub fn new(cpu: u32) -> Self {
+		Self {
+			cpu,
+			nr_running: 0,
+			current: None,
+			cfs: CfsRunQueue::new(),
+			rt: RtRunQueue::new(),
+			idle_task: None,
+			clock: 0,
+			clock_task: 0,
+		}
+	}
+
+	/// Update run queue clock
+	pub fn update_rq_clock(&mut self) {
+		self.clock = time::get_time_ns();
+		self.clock_task = self.clock;
+	}
+
+	/// Enqueue a task
+	pub fn enqueue_task(&mut self, se: SchedEntity) {
+		match se.policy {
+			SchedulerPolicy::Normal
+			| SchedulerPolicy::Batch
+			| SchedulerPolicy::Idle => {
+				self.cfs.enqueue_task(se);
+			}
+			SchedulerPolicy::Fifo | SchedulerPolicy::RoundRobin => {
+				self.rt.enqueue_task(se);
+			}
+			SchedulerPolicy::Deadline => {
+				// TODO: implement deadline scheduler
+				self.cfs.enqueue_task(se);
+			}
+		}
+		self.nr_running += 1;
+	}
+
+	/// Dequeue a task
+	pub fn dequeue_task(&mut self, se: &SchedEntity) -> bool {
+		let result = match se.policy {
+			SchedulerPolicy::Normal
+			| SchedulerPolicy::Batch
+			| SchedulerPolicy::Idle => self.cfs.dequeue_task(se),
+			SchedulerPolicy::Fifo | SchedulerPolicy::RoundRobin => {
+				self.rt.dequeue_task(se)
+			}
+			SchedulerPolicy::Deadline => self.cfs.dequeue_task(se),
+		};
+
+		if result {
+			self.nr_running -= 1;
+		}
+		result
+	}
+
+	/// Pick next task to run
+	pub fn pick_next_task(&mut self) -> Option<SchedEntity> {
+		// Real-time tasks have priority
+		if let Some(se) = self.rt.pick_next_task() {
+			return Some(se);
+		}
+
+		// Then CFS tasks
+		if let Some(se) = self.cfs.pick_next_task() {
+			return Some(se);
+		}
+
+		// Finally, idle task
+		self.idle_task.clone()
+	}
+}
+
+/// Global scheduler state
+static SCHEDULER: Spinlock<Scheduler> = Spinlock::new(Scheduler::new());
+static SCHEDULE_CLOCK: AtomicU64 = AtomicU64::new(0);
+
+/// Main scheduler structure
+struct Scheduler {
+	run_queues: Vec<RunQueue>,
+	nr_cpus: u32,
+	entities: BTreeMap<Tid, SchedEntity>,
+	need_resched: bool,
+	cfs: CfsRunQueue,
+	rt: RtRunQueue,
+	current: Option<Tid>,
+	nr_switches: u64,
+}
+
+impl Scheduler {
+	const fn new() -> Self {
+		Self {
+			run_queues: Vec::new(),
+			nr_cpus: 1, // Single CPU for now
+			entities: BTreeMap::new(),
+			need_resched: false,
+			cfs: CfsRunQueue {
+				tasks_timeline: BTreeMap::new(),
+				min_vruntime: 0,
+				nr_running: 0,
+				load_weight: 0,
+				runnable_weight: 0,
+			},
+			rt: RtRunQueue {
+				runqueue: VecDeque::new(),
+				nr_running: 0,
+			},
+			current: None,
+			nr_switches: 0,
+		}
+	}
+
+	fn init(&mut self) -> Result<()> {
+		// Create run queues for each CPU
+		for cpu in 0..self.nr_cpus {
+			let mut rq = RunQueue::new(cpu);
+
+			// Create idle task for this CPU
+			let idle_se = SchedEntity::new(
+				crate::process::allocate_tid(),
+				SchedulerPolicy::Idle,
+				MAX_NICE,
+			);
+			rq.idle_task = Some(idle_se);
+
+			self.run_queues.push(rq);
+		}
+		Ok(())
+	}
+
+	fn add_task(&mut self, tid: Tid, policy: SchedulerPolicy, nice: i32) {
+		let se = SchedEntity::new(tid, policy, nice);
+		self.entities.insert(tid, se.clone());
+
+		// Add to CPU 0's run queue for simplicity
+		if let Some(rq) = self.run_queues.get_mut(0) {
+			rq.enqueue_task(se);
+		}
+	}
+
+	fn remove_task(&mut self, tid: Tid) {
+		if let Some(se) = self.entities.remove(&tid) {
+			// Remove from all run queues
+			for rq in &mut self.run_queues {
+				rq.dequeue_task(&se);
+			}
+		}
+	}
+
+	fn schedule(&mut self) -> Option<Tid> {
+		// Simple single-CPU scheduling for now
+		if let Some(rq) = self.run_queues.get_mut(0) {
+			rq.update_rq_clock();
+
+			if let Some(se) = rq.pick_next_task() {
+				rq.current = Some(se.clone());
+				return Some(se.tid);
+			}
+		}
+		None
+	}
+
+	/// Pick next task to run
+	fn pick_next_task(&mut self) -> Option<Tid> {
+		// Try CFS first
+		if let Some(se) = self.cfs.pick_next_task() {
+			self.current = Some(se.tid);
+			return Some(se.tid);
+		}
+
+		// Then try RT
+		if let Some(se) = self.rt.pick_next_task() {
+			self.current = Some(se.tid);
+			return Some(se.tid);
+		}
+
+		None
+	}
+
+	/// Switch to a task
+	fn switch_to(&mut self, tid: Tid) {
+		// Save current task's context
+		if let Some(current_tid) = self.current {
+			if current_tid != tid {
+				// Look up current and next threads
+				// We need to use a scope to ensure the lock is dropped before switching
+				let (current_ctx_ptr, next_ctx_ptr) = {
+					let mut process_table = PROCESS_TABLE.lock();
+
+					let (current_thread, next_thread) = process_table
+						.find_two_threads_mut(current_tid, tid);
+
+					let current_ptr = if let Some(t) = current_thread {
+						&mut t.context as *mut Context
+					} else {
+						return; // Current thread not found?
+					};
+
+					let next_ptr = if let Some(t) = next_thread {
+						&t.context as *const Context
+					} else {
+						return; // Next thread not found
+					};
+
+					(current_ptr, next_ptr)
+				};
+
+				// Update scheduler state
+				self.current = Some(tid);
+				self.nr_switches += 1;
+
+				// Perform the context switch
+				// SAFETY: We have valid pointers to the contexts and we've dropped the lock
+				unsafe {
+					switch_context(&mut *current_ctx_ptr, &*next_ctx_ptr);
+				}
+
+				return;
+			}
+		}
+
+		// First task or same task
+		self.current = Some(tid);
+		self.nr_switches += 1;
+	}
+
+	/// Set need resched flag
+	fn set_need_resched(&mut self) {
+		self.need_resched = true;
+	}
+}
+
+/// Initialize the scheduler
+pub fn init() -> Result<()> {
+	let mut scheduler = SCHEDULER.lock();
+	scheduler.init()?;
+
+	crate::info!("Scheduler initialized with {} CPUs", scheduler.nr_cpus);
+	Ok(())
+}
+
+/// Add a task to the scheduler
+pub fn add_task(pid: crate::types::Pid) -> Result<()> {
+	let mut scheduler = SCHEDULER.lock();
+
+	// Create a scheduler entity for the process
+	let tid = crate::types::Tid(pid.0); // Simple mapping for now
+	let se = SchedEntity::new(tid, SchedulerPolicy::Normal, DEFAULT_PRIO);
+
+	// Add to CFS runqueue
+	scheduler.cfs.enqueue_task(se);
+
+	Ok(())
+}
+
+/// Remove a task from the scheduler
+pub fn remove_task(pid: crate::types::Pid) -> Result<()> {
+	let mut scheduler = SCHEDULER.lock();
+
+	// Remove from all runqueues
+	let tid = crate::types::Tid(pid.0);
+
+	// Create a minimal SchedEntity for removal
+	let se = SchedEntity::new(tid, SchedulerPolicy::Normal, DEFAULT_PRIO);
+	scheduler.cfs.dequeue_task(&se);
+	scheduler.rt.dequeue_task(&se);
+
+	Ok(())
+}
+
+/// Schedule next task (called from syscall exit or timer interrupt)
+pub fn schedule() {
+	let mut scheduler = SCHEDULER.lock();
+
+	// Pick next task to run
+	if let Some(next) = scheduler.pick_next_task() {
+		// Switch to next task
+		scheduler.switch_to(next);
+	}
+}
+
+/// Get current running task
+pub fn current_task() -> Option<crate::types::Pid> {
+	let scheduler = SCHEDULER.lock();
+	scheduler.current.map(|tid| crate::types::Pid(tid.0))
+}
+
+/// Yield current task (alias for yield_task)
+pub fn yield_now() {
+	yield_task();
+}
+
+/// Yield current task
+pub fn yield_task() {
+	let mut scheduler = SCHEDULER.lock();
+	scheduler.set_need_resched();
+}
+
+/// Sleep current task for specified duration
+pub fn sleep_task(duration_ms: u64) {
+	// TODO: implement proper sleep mechanism with timer integration
+	// For now, just yield
+	yield_task();
+}
+
+/// Wake up a task
+pub fn wake_task(pid: crate::types::Pid) -> Result<()> {
+	let mut scheduler = SCHEDULER.lock();
+	let tid = crate::types::Tid(pid.0);
+
+	// TODO: Move from wait queue to runqueue
+	// For now, just ensure it's in the runqueue
+	let se = SchedEntity::new(tid, SchedulerPolicy::Normal, DEFAULT_PRIO);
+	scheduler.cfs.enqueue_task(se);
+
+	Ok(())
+}
+
+/// Set task priority
+pub fn set_task_priority(pid: crate::types::Pid, priority: i32) -> Result<()> {
+	let mut scheduler = SCHEDULER.lock();
+	let tid = crate::types::Tid(pid.0);
+
+	// TODO: Update priority in runqueue
+	// This would require finding the task and updating its priority
+
+	Ok(())
+}
+
+/// Get scheduler statistics
+pub fn get_scheduler_stats() -> SchedulerStats {
+	let scheduler = SCHEDULER.lock();
+	SchedulerStats {
+		total_tasks: (scheduler.cfs.nr_running + scheduler.rt.nr_running) as usize,
+		running_tasks: if scheduler.current.is_some() { 1 } else { 0 },
+		context_switches: scheduler.nr_switches,
+		load_average: scheduler.cfs.load_weight as f64 / 1024.0,
+	}
+}
+
+/// Scheduler statistics
+#[derive(Debug, Clone)]
+pub struct SchedulerStats {
+	pub total_tasks: usize,
+	pub running_tasks: usize,
+	pub context_switches: u64,
+	pub load_average: f64,
+}
+
+/// Calculate time slice for a task based on its weight
+fn calculate_time_slice(se: &SchedEntity) -> u64 {
+	// Linux-like time slice calculation
+	let sched_latency = 6_000_000; // 6ms in nanoseconds
+	let min_granularity = 750_000; // 0.75ms in nanoseconds
+
+	// Time slice proportional to weight
+	let time_slice = sched_latency * se.load_weight as u64 / 1024;
+	core::cmp::max(time_slice, min_granularity)
+}
+
+/// Timer tick - called from timer interrupt
+pub fn scheduler_tick() {
+	SCHEDULE_CLOCK.fetch_add(1, Ordering::Relaxed);
+
+	let mut scheduler = SCHEDULER.lock();
+
+	// Update current task's runtime
+	if let Some(rq) = scheduler.run_queues.get_mut(0) {
+		if let Some(ref mut current) = rq.current {
+			let now = rq.clock;
+			let delta = now - current.exec_start;
+			current.sum_exec_runtime += delta;
+			current.update_vruntime(delta);
+			current.exec_start = now;
+
+			// Check if we need to reschedule
+			// For CFS, check if current task has run long enough
+			if current.policy == SchedulerPolicy::Normal {
+				let time_slice = calculate_time_slice(current);
+				if current.sum_exec_runtime - current.prev_sum_exec_runtime
+					>= time_slice
+				{
+					scheduler.set_need_resched();
+				}
+			}
+		}
+	}
+}
+
+/// Perform a manual context switch to a specific task
+/// This is used by the enhanced scheduler to execute its scheduling decisions
+pub fn context_switch_to(tid: Tid) {
+	let mut scheduler = SCHEDULER.lock();
+	scheduler.switch_to(tid);
+}

kernel/src/stress_test.rs

@@ -0,0 +1,278 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! System stress testing and load generation
+
+use alloc::{format, string::String, vec::Vec};
+
+use crate::error::Result;
+use crate::time::get_jiffies;
+use crate::types::Jiffies;
+
+/// Stress test types
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum StressTestType {
+	Memory,
+	CPU,
+	IO,
+	FileSystem,
+	Network,
+	All,
+}
+
+/// Stress test results
+#[derive(Debug, Clone)]
+pub struct StressTestResult {
+	pub test_type: StressTestType,
+	pub duration_jiffies: u64,
+	pub operations_completed: u64,
+	pub operations_per_second: u64,
+	pub errors_encountered: u64,
+	pub details: String,
+}
+
+/// Memory stress test - allocate and free memory rapidly
+pub fn memory_stress_test(duration_seconds: u64) -> Result<StressTestResult> {
+	let start_time = get_jiffies();
+	let duration_jiffies = duration_seconds * 1000; // Convert to jiffies (1000 Hz)
+	let mut operations = 0u64;
+	let mut errors = 0u64;
+	let mut allocations: Vec<*mut u8> = Vec::new();
+
+	while (get_jiffies() - start_time).as_u64() < duration_jiffies {
+		// Allocate memory
+		match crate::memory::kmalloc::kmalloc(1024) {
+			Ok(ptr) => {
+				allocations.push(ptr);
+				operations += 1;
+
+				// Free every 100 allocations to prevent exhaustion
+				if allocations.len() >= 100 {
+					for ptr in allocations.drain(..) {
+						crate::memory::kmalloc::kfree(ptr);
+						operations += 1;
+					}
+				}
+			}
+			Err(_) => {
+				errors += 1;
+				// Free all allocations on error
+				for ptr in allocations.drain(..) {
+					crate::memory::kmalloc::kfree(ptr);
+				}
+			}
+		}
+	}
+
+	// Clean up remaining allocations
+	for ptr in allocations.drain(..) {
+		crate::memory::kmalloc::kfree(ptr);
+		operations += 1;
+	}
+
+	let actual_duration = (get_jiffies() - start_time).as_u64();
+	let ops_per_second = if actual_duration > 0 {
+		(operations * 1000) / actual_duration
+	} else {
+		0
+	};
+
+	Ok(StressTestResult {
+		test_type: StressTestType::Memory,
+		duration_jiffies: actual_duration,
+		operations_completed: operations,
+		operations_per_second: ops_per_second,
+		errors_encountered: errors,
+		details: format!("Allocated/freed {} KB total", operations / 2),
+	})
+}
+
+/// CPU stress test - perform intensive calculations
+pub fn cpu_stress_test(duration_seconds: u64) -> Result<StressTestResult> {
+	let start_time = get_jiffies();
+	let duration_jiffies = duration_seconds * 1000;
+	let mut operations = 0u64;
+	let mut result = 1u64;
+
+	while (get_jiffies() - start_time).as_u64() < duration_jiffies {
+		// Perform some CPU-intensive operations
+		for i in 1..1000 {
+			result = result.wrapping_mul(i).wrapping_add(i * i);
+			operations += 1;
+		}
+
+		// Prevent optimization from removing the loop
+		if result == 0 {
+			break;
+		}
+	}
+
+	let actual_duration = (get_jiffies() - start_time).as_u64();
+	let ops_per_second = if actual_duration > 0 {
+		(operations * 1000) / actual_duration
+	} else {
+		0
+	};
+
+	Ok(StressTestResult {
+		test_type: StressTestType::CPU,
+		duration_jiffies: actual_duration,
+		operations_completed: operations,
+		operations_per_second: ops_per_second,
+		errors_encountered: 0,
+		details: format!("Final calculation result: {}", result),
+	})
+}
+
+/// File system stress test - create, write, read, delete files
+pub fn filesystem_stress_test(duration_seconds: u64) -> Result<StressTestResult> {
+	let start_time = get_jiffies();
+	let duration_jiffies = duration_seconds * 1000;
+	let mut operations = 0u64;
+	let mut errors = 0u64;
+	let mut file_counter = 0u32;
+
+	while (get_jiffies() - start_time).as_u64() < duration_jiffies {
+		let filename = format!("/tmp/stress_test_{}", file_counter);
+		file_counter += 1;
+
+		// Create file
+		match crate::memfs::fs_create_file(&filename) {
+			Ok(()) => operations += 1,
+			Err(_) => errors += 1,
+		}
+
+		// Write to file (not implemented in memfs, but count the attempt)
+		operations += 1;
+
+		// Read file (attempt)
+		match crate::memfs::fs_read(&filename) {
+			Ok(_) => operations += 1,
+			Err(_) => errors += 1,
+		}
+
+		// Delete file
+		match crate::memfs::fs_remove(&filename) {
+			Ok(()) => operations += 1,
+			Err(_) => errors += 1,
+		}
+	}
+
+	let actual_duration = (get_jiffies() - start_time).as_u64();
+	let ops_per_second = if actual_duration > 0 {
+		(operations * 1000) / actual_duration
+	} else {
+		0
+	};
+
+	Ok(StressTestResult {
+		test_type: StressTestType::FileSystem,
+		duration_jiffies: actual_duration,
+		operations_completed: operations,
+		operations_per_second: ops_per_second,
+		errors_encountered: errors,
+		details: format!("Created and deleted {} files", file_counter),
+	})
+}
+
+/// Combined stress test
+pub fn combined_stress_test(duration_seconds: u64) -> Result<Vec<StressTestResult>> {
+	let mut results = Vec::new();
+
+	// Run tests in sequence (parallel would be more stressful but harder to
+	// implement)
+	let per_test_duration = duration_seconds / 3;
+
+	if let Ok(result) = memory_stress_test(per_test_duration) {
+		results.push(result);
+	}
+
+	if let Ok(result) = cpu_stress_test(per_test_duration) {
+		results.push(result);
+	}
+
+	if let Ok(result) = filesystem_stress_test(per_test_duration) {
+		results.push(result);
+	}
+
+	Ok(results)
+}
+
+/// Generate system load for testing purposes
+pub fn generate_load(test_type: StressTestType, duration_seconds: u64) -> Result<StressTestResult> {
+	// Add diagnostic entry about starting stress test
+	crate::diagnostics::add_diagnostic(
+		crate::diagnostics::DiagnosticCategory::Kernel,
+		crate::diagnostics::HealthStatus::Warning,
+		&format!(
+			"Starting {:?} stress test for {} seconds",
+			test_type, duration_seconds
+		),
+		None,
+	);
+
+	let result = match test_type {
+		StressTestType::Memory => memory_stress_test(duration_seconds),
+		StressTestType::CPU => cpu_stress_test(duration_seconds),
+		StressTestType::FileSystem => filesystem_stress_test(duration_seconds),
+		StressTestType::IO | StressTestType::Network => {
+			// Not implemented yet
+			Err(crate::error::Error::NotSupported)
+		}
+		StressTestType::All => {
+			// Run combined test and return the first result
+			match combined_stress_test(duration_seconds) {
+				Ok(results) if !results.is_empty() => Ok(results[0].clone()),
+				Ok(_) => Err(crate::error::Error::Generic),
+				Err(e) => Err(e),
+			}
+		}
+	};
+
+	// Add diagnostic entry about completing stress test
+	match &result {
+		Ok(test_result) => {
+			crate::diagnostics::add_diagnostic(
+				crate::diagnostics::DiagnosticCategory::Kernel,
+				crate::diagnostics::HealthStatus::Healthy,
+				&format!(
+					"Completed {:?} stress test: {} ops/sec",
+					test_result.test_type, test_result.operations_per_second
+				),
+				Some(&format!(
+					"Duration: {}ms, Operations: {}, Errors: {}",
+					test_result.duration_jiffies,
+					test_result.operations_completed,
+					test_result.errors_encountered
+				)),
+			);
+		}
+		Err(e) => {
+			crate::diagnostics::add_diagnostic(
+				crate::diagnostics::DiagnosticCategory::Kernel,
+				crate::diagnostics::HealthStatus::Critical,
+				&format!("Stress test failed: {}", e),
+				None,
+			);
+		}
+	}
+
+	result
+}
+
+/// Format stress test results for display
+pub fn format_stress_test_result(result: &StressTestResult) -> String {
+	format!(
+		"{:?} Stress Test Results:\n\
+         Duration: {} ms\n\
+         Operations: {}\n\
+         Rate: {} ops/sec\n\
+         Errors: {}\n\
+         Details: {}",
+		result.test_type,
+		result.duration_jiffies,
+		result.operations_completed,
+		result.operations_per_second,
+		result.errors_encountered,
+		result.details
+	)
+}

kernel/src/sync.rs

@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Synchronization primitives
+
+// Re-export common synchronization types
+pub use alloc::sync::Arc;
+use core::cell::UnsafeCell;
+use core::ops::{Deref, DerefMut};
+use core::sync::atomic::{AtomicBool, Ordering};
+
+pub use spin::Mutex;
+pub use spin::RwLock;
+
+/// Spinlock implementation
+pub struct Spinlock<T> {
+	locked: AtomicBool,
+	data: UnsafeCell<T>,
+}
+
+unsafe impl<T: Send> Sync for Spinlock<T> {}
+unsafe impl<T: Send> Send for Spinlock<T> {}
+
+impl<T> Spinlock<T> {
+	pub const fn new(data: T) -> Self {
+		Self {
+			locked: AtomicBool::new(false),
+			data: UnsafeCell::new(data),
+		}
+	}
+
+	pub fn lock(&self) -> SpinlockGuard<'_, T> {
+		while self
+			.locked
+			.compare_exchange_weak(false, true, Ordering::Acquire, Ordering::Relaxed)
+			.is_err()
+		{
+			// Busy wait
+			while self.locked.load(Ordering::Relaxed) {
+				core::hint::spin_loop();
+			}
+		}
+
+		SpinlockGuard { lock: self }
+	}
+
+	pub fn try_lock(&self) -> Option<SpinlockGuard<'_, T>> {
+		if self.locked
+			.compare_exchange(false, true, Ordering::Acquire, Ordering::Relaxed)
+			.is_ok()
+		{
+			Some(SpinlockGuard { lock: self })
+		} else {
+			None
+		}
+	}
+}
+
+pub struct SpinlockGuard<'a, T> {
+	lock: &'a Spinlock<T>,
+}
+
+impl<T> Deref for SpinlockGuard<'_, T> {
+	type Target = T;
+
+	fn deref(&self) -> &Self::Target {
+		unsafe { &*self.lock.data.get() }
+	}
+}
+
+impl<T> DerefMut for SpinlockGuard<'_, T> {
+	fn deref_mut(&mut self) -> &mut Self::Target {
+		unsafe { &mut *self.lock.data.get() }
+	}
+}
+
+impl<T> Drop for SpinlockGuard<'_, T> {
+	fn drop(&mut self) {
+		self.lock.locked.store(false, Ordering::Release);
+	}
+}
+
+// Note: We use spin::Mutex and spin::RwLock for actual implementations
+// The Spinlock above is for cases where we need a simple spinlock specifically

kernel/src/syscall.rs

@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! System call interface
+use crate::error::Result;
+
+pub fn init() -> Result<()> {
+	Ok(())
+}

kernel/src/syscalls.rs

@@ -0,0 +1,518 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! System call interface - Linux compatible
+
+use crate::error::{Error, Result};
+use crate::process::{allocate_pid, current_process, find_process};
+use crate::types::Pid;
+
+/// System call numbers (Linux compatible subset)
+#[derive(Debug, Clone, Copy)]
+#[repr(u64)]
+pub enum SyscallNumber {
+	Read = 0,
+	Write = 1,
+	Open = 2,
+	Close = 3,
+	Stat = 4,
+	Fstat = 5,
+	Lseek = 8,
+	Mmap = 9,
+	Munmap = 11,
+	Brk = 12,
+	Ioctl = 16,
+	Access = 21,
+	Pipe = 22,
+	Select = 23,
+	Socket = 41,
+	Connect = 42,
+	Accept = 43,
+	Fork = 57,
+	Execve = 59,
+	Exit = 60,
+	Wait4 = 61,
+	Kill = 62,
+	Getpid = 39,
+	Getppid = 110,
+	Getuid = 102,
+	Setuid = 105,
+	Getgid = 104,
+	Setgid = 106,
+	Gettid = 186,
+	Clone = 56,
+	Futex = 202,
+}
+
+/// System call arguments structure
+#[derive(Debug)]
+pub struct SyscallArgs {
+	pub syscall_num: u64,
+	pub arg0: u64,
+	pub arg1: u64,
+	pub arg2: u64,
+	pub arg3: u64,
+	pub arg4: u64,
+	pub arg5: u64,
+}
+
+/// System call dispatcher
+pub fn handle_syscall(args: SyscallArgs) -> u64 {
+	let result = match args.syscall_num {
+		// Process management
+		57 => sys_fork(),                                            // fork
+		59 => sys_execve(args.arg0, args.arg1, args.arg2),           // execve
+		60 => sys_exit(args.arg0 as i32),                            // exit
+		61 => sys_wait4(args.arg0, args.arg1, args.arg2, args.arg3), // wait4
+		62 => sys_kill(args.arg0 as i32, args.arg1 as i32),          // kill
+
+		// Process info
+		39 => Ok(sys_getpid() as u64),   // getpid
+		110 => Ok(sys_getppid() as u64), // getppid
+		102 => Ok(sys_getuid() as u64),  // getuid
+		104 => Ok(sys_getgid() as u64),  // getgid
+		186 => Ok(sys_gettid() as u64),  // gettid
+
+		// File operations
+		0 => sys_read(args.arg0 as i32, args.arg1, args.arg2), // read
+		1 => sys_write(args.arg0 as i32, args.arg1, args.arg2), // write
+		2 => sys_open(args.arg0, args.arg1 as i32, args.arg2 as u32), // open
+		3 => sys_close(args.arg0 as i32),                      // close
+
+		// Memory management
+		9 => sys_mmap(
+			args.arg0,
+			args.arg1,
+			args.arg2 as i32,
+			args.arg3 as i32,
+			args.arg4 as i32,
+			args.arg5 as i64,
+		), // mmap
+		11 => sys_munmap(args.arg0, args.arg1), // munmap
+		12 => sys_brk(args.arg0),               // brk
+
+		// Unimplemented syscalls
+		_ => Err(Error::ENOSYS),
+	};
+
+	match result {
+		Ok(value) => value,
+		Err(error) => (-error.to_errno()) as u64,
+	}
+}
+
+/// Process management syscalls
+pub fn sys_fork() -> Result<u64> {
+	use crate::process::create_process;
+	use crate::scheduler::add_task;
+
+	// Get current process
+	let current = current_process().ok_or(Error::ESRCH)?;
+
+	// Fork the process
+	let child = current.fork()?;
+	let child_pid = child.pid;
+
+	// Add child to process table and scheduler
+	let mut table = crate::process::PROCESS_TABLE.lock();
+	table.add_process(child.clone());
+	drop(table);
+
+	// Add to scheduler
+	add_task(child_pid)?;
+
+	// Return child PID to parent (in child, this would return 0)
+	Ok(child_pid.0 as u64)
+}
+
+pub fn sys_execve(filename: u64, argv: u64, envp: u64) -> Result<u64> {
+	use crate::memory::{copy_string_from_user, UserPtr};
+
+	// Copy filename from user space
+	let user_ptr = UserPtr::from_const(filename as *const u8)?;
+	let filename_str = copy_string_from_user(user_ptr, 256)?;
+
+	// Get current process
+	let mut current = current_process().ok_or(Error::ESRCH)?;
+
+	// Execute new program (with empty args for now)
+	current.exec(&filename_str, alloc::vec![])?;
+
+	// This doesn't return on success
+	Ok(0)
+}
+
+pub fn sys_exit(exit_code: i32) -> Result<u64> {
+	use crate::scheduler::remove_task;
+
+	// Get current process
+	if let Some(mut current) = current_process() {
+		// Set exit code and mark as zombie
+		current.exit(exit_code);
+
+		// Remove from scheduler
+		let _ = remove_task(current.pid);
+
+		// In a real implementation, this would:
+		// 1. Free all process resources
+		// 2. Notify parent process
+		// 3. Reparent children to init
+		// 4. Schedule next process
+
+		// Signal scheduler to switch to next process
+		crate::scheduler::schedule();
+	}
+
+	// This syscall doesn't return
+	loop {
+		unsafe { core::arch::asm!("hlt") };
+	}
+}
+
+pub fn sys_wait4(pid: u64, status: u64, options: u64, rusage: u64) -> Result<u64> {
+	use crate::memory::{copy_to_user, UserPtr};
+
+	// Get current process
+	let current = current_process().ok_or(Error::ESRCH)?;
+
+	// Wait for child process
+	let (child_pid, exit_status) = current.wait()?;
+
+	// If status pointer is provided, write exit status
+	if status != 0 {
+		let status_ptr = UserPtr::new(status as *mut i32)?;
+		copy_to_user(status_ptr.cast(), &exit_status.to_ne_bytes())?;
+	}
+
+	Ok(child_pid.0 as u64)
+}
+
+pub fn sys_kill(pid: i32, signal: i32) -> Result<u64> {
+	if let Some(mut process) = find_process(Pid(pid as u32)) {
+		process.send_signal(signal)?;
+		Ok(0)
+	} else {
+		Err(Error::ESRCH)
+	}
+}
+
+/// Process info syscalls
+pub fn sys_getpid() -> u32 {
+	current_process().map(|p| p.pid.0).unwrap_or(0)
+}
+
+pub fn sys_getppid() -> u32 {
+	current_process()
+		.and_then(|p| p.parent)
+		.map(|p| p.0)
+		.unwrap_or(0)
+}
+
+pub fn sys_getuid() -> u32 {
+	current_process().map(|p| p.uid.0).unwrap_or(0)
+}
+
+pub fn sys_getgid() -> u32 {
+	current_process().map(|p| p.gid.0).unwrap_or(0)
+}
+
+pub fn sys_gettid() -> u32 {
+	// For now, return PID (single-threaded processes)
+	sys_getpid()
+}
+
+/// File operation syscalls
+pub fn sys_read(fd: i32, buf: u64, count: u64) -> Result<u64> {
+	use crate::fs::{get_file_descriptor, read_file};
+	use crate::memory::{copy_to_user, UserPtr};
+
+	// Validate parameters
+	if count == 0 {
+		return Ok(0);
+	}
+
+	// Get file from file descriptor table
+	let file = get_file_descriptor(fd).ok_or(Error::EBADF)?;
+
+	// Create a kernel buffer to read into
+	let mut kernel_buf = alloc::vec![0u8; count as usize];
+
+	// Read from file
+	let bytes_read = read_file(&file, &mut kernel_buf)?;
+
+	// Copy to user buffer
+	let user_ptr = UserPtr::new(buf as *mut u8)?;
+	copy_to_user(user_ptr, &kernel_buf[..bytes_read])?;
+
+	Ok(bytes_read as u64)
+}
+
+pub fn sys_write(fd: i32, buf: u64, count: u64) -> Result<u64> {
+	use crate::fs::{get_file_descriptor, write_file};
+	use crate::memory::{copy_from_user, UserPtr};
+
+	// Validate parameters
+	if count == 0 {
+		return Ok(0);
+	}
+
+	// Handle stdout/stderr specially for now
+	if fd == 1 || fd == 2 {
+		// Create kernel buffer and copy from user
+		let mut kernel_buf = alloc::vec![0u8; count as usize];
+		let user_ptr = UserPtr::from_const(buf as *const u8)?;
+		copy_from_user(&mut kernel_buf, user_ptr)?;
+
+		// Write to console (for debugging)
+		if let Ok(s) = core::str::from_utf8(&kernel_buf) {
+			crate::print!("{}", s);
+		}
+
+		return Ok(count);
+	}
+
+	// Get file from file descriptor table
+	let file = get_file_descriptor(fd).ok_or(Error::EBADF)?;
+
+	// Create kernel buffer and copy from user
+	let mut kernel_buf = alloc::vec![0u8; count as usize];
+	let user_ptr = UserPtr::from_const(buf as *const u8)?;
+	copy_from_user(&mut kernel_buf, user_ptr)?;
+
+	// Write to file
+	let bytes_written = write_file(&file, &kernel_buf)?;
+
+	Ok(bytes_written as u64)
+}
+
+pub fn sys_open(filename: u64, flags: i32, mode: u32) -> Result<u64> {
+	use crate::fs::{allocate_file_descriptor, open_file};
+	use crate::memory::{copy_string_from_user, UserPtr};
+
+	// Copy filename from user space
+	let user_ptr = UserPtr::from_const(filename as *const u8)?;
+	let filename_str = copy_string_from_user(user_ptr, 256)?; // Max 256 chars
+
+	// Open file in VFS
+	let file = open_file(&filename_str, flags, mode)?;
+
+	// Allocate file descriptor and add to process file table
+	let fd = allocate_file_descriptor(file)?;
+
+	Ok(fd as u64)
+}
+
+pub fn sys_close(fd: i32) -> Result<u64> {
+	use crate::fs::close_file_descriptor;
+
+	// Close file descriptor
+	close_file_descriptor(fd)?;
+
+	Ok(0)
+}
+
+/// Memory management syscalls
+pub fn sys_mmap(
+	addr: u64,
+	length: u64,
+	prot: i32,
+	flags: i32,
+	fd: i32,
+	offset: i64,
+) -> Result<u64> {
+	use crate::memory::{allocate_virtual_memory, VirtAddr, VmaArea};
+
+	// Validate parameters
+	if length == 0 {
+		return Err(Error::EINVAL);
+	}
+
+	// Align length to page boundary
+	let page_size = 4096u64;
+	let aligned_length = (length + page_size - 1) & !(page_size - 1);
+
+	// Allocate virtual memory region
+	let vma = if addr == 0 {
+		// Let kernel choose address
+		allocate_virtual_memory(aligned_length, prot as u32, flags as u32)?
+	} else {
+		// Use specified address (with validation)
+		let virt_addr = VirtAddr::new(addr as usize);
+
+		// Validate that the address range is available
+		if !crate::memory::is_virtual_range_free(virt_addr, aligned_length) {
+			return Err(Error::EEXIST);
+		}
+
+		// Allocate and map the memory
+		let vma = allocate_virtual_memory(aligned_length, prot as u32, flags as u32)?;
+		vma
+	};
+
+	// Handle file mapping
+	if fd >= 0 {
+		// Map file into memory - simplified implementation
+		crate::info!("File mapping requested for fd {} at offset {}", fd, offset);
+		// In a real implementation, this would:
+		// 1. Get the file descriptor from current process
+		// 2. Map file pages into the VMA
+		// 3. Set up page fault handler for demand paging
+	}
+
+	Ok(vma.vm_start.as_usize() as u64)
+}
+
+pub fn sys_munmap(addr: u64, length: u64) -> Result<u64> {
+	use crate::memory::{free_virtual_memory, VirtAddr};
+
+	// Validate parameters
+	if length == 0 {
+		return Err(Error::EINVAL);
+	}
+
+	// Align to page boundaries
+	let page_size = 4096u64;
+	let aligned_addr = addr & !(page_size - 1);
+	let aligned_length = (length + page_size - 1) & !(page_size - 1);
+
+	// Free virtual memory region
+	free_virtual_memory(VirtAddr::new(aligned_addr as usize), aligned_length)?;
+
+	Ok(0)
+}
+
+pub fn sys_brk(addr: u64) -> Result<u64> {
+	use crate::memory::{get_heap_end, set_heap_end, VirtAddr};
+
+	// Get current heap end
+	let current_brk = get_heap_end();
+
+	if addr == 0 {
+		// Return current heap end
+		return Ok(current_brk.as_usize() as u64);
+	}
+
+	let new_brk = VirtAddr::new(addr as usize);
+
+	// Validate new address
+	if new_brk < current_brk {
+		// Shrinking heap - free pages
+		let pages_to_free = (current_brk.as_usize() - new_brk.as_usize() + 4095) / 4096;
+		crate::info!("Shrinking heap, freeing {} pages", pages_to_free);
+		// In a real implementation, this would free the actual pages
+	} else if new_brk > current_brk {
+		// Expanding heap - allocate pages
+		let pages_to_alloc = (new_brk.as_usize() - current_brk.as_usize() + 4095) / 4096;
+		crate::info!("Expanding heap, allocating {} pages", pages_to_alloc);
+		// In a real implementation, this would allocate and map new
+		// pages
+	}
+
+	// Update heap end
+	set_heap_end(new_brk)?;
+
+	Ok(new_brk.as_usize() as u64)
+}
+
+/// Architecture-specific syscall entry point
+#[cfg(target_arch = "x86_64")]
+pub mod arch {
+	use super::*;
+
+	/// x86_64 syscall entry point (called from assembly)
+	#[no_mangle]
+	pub extern "C" fn syscall_entry(
+		syscall_num: u64,
+		arg0: u64,
+		arg1: u64,
+		arg2: u64,
+		arg3: u64,
+		arg4: u64,
+		arg5: u64,
+	) -> u64 {
+		let args = SyscallArgs {
+			syscall_num,
+			arg0,
+			arg1,
+			arg2,
+			arg3,
+			arg4,
+			arg5,
+		};
+
+		handle_syscall(args)
+	}
+}
+
+/// Initialize syscall handling
+pub fn init_syscalls() -> Result<()> {
+	// Set up syscall entry point for x86_64
+	#[cfg(target_arch = "x86_64")]
+	unsafe {
+		// Enable SYSCALL/SYSRET instructions
+		// Set up STAR MSR (syscall target address register)
+		let star_msr = 0xC0000081u32;
+		let lstar_msr = 0xC0000082u32;
+		let sfmask_msr = 0xC0000084u32;
+
+		// Set up kernel and user code segments in STAR
+		// Format: [63:48] user CS, [47:32] kernel CS
+		let star_value = (0x1Bu64 << 48) | (0x08u64 << 32);
+
+		// Write STAR MSR
+		core::arch::asm!(
+		    "wrmsr",
+		    in("ecx") star_msr,
+		    in("eax") (star_value & 0xFFFFFFFF) as u32,
+		    in("edx") (star_value >> 32) as u32,
+		    options(nostack, preserves_flags)
+		);
+
+		// Set LSTAR to point to our syscall entry
+		let entry_addr = arch::syscall_entry as *const () as u64;
+		core::arch::asm!(
+		    "wrmsr",
+		    in("ecx") lstar_msr,
+		    in("eax") (entry_addr & 0xFFFFFFFF) as u32,
+		    in("edx") (entry_addr >> 32) as u32,
+		    options(nostack, preserves_flags)
+		);
+
+		// Set SFMASK to mask interrupt flag during syscall
+		core::arch::asm!(
+		    "wrmsr",
+		    in("ecx") sfmask_msr,
+		    in("eax") 0x200u32, // Mask IF (interrupt flag)
+		    in("edx") 0u32,
+		    options(nostack, preserves_flags)
+		);
+
+		// Enable SCE (System Call Extensions) in EFER
+		let efer_msr = 0xC0000080u32;
+		let mut efer_low: u32;
+		let mut efer_high: u32;
+
+		// Read current EFER
+		core::arch::asm!(
+		    "rdmsr",
+		    in("ecx") efer_msr,
+		    out("eax") efer_low,
+		    out("edx") efer_high,
+		    options(nostack, preserves_flags)
+		);
+
+		// Set SCE bit (bit 0)
+		efer_low |= 1;
+
+		// Write back EFER
+		core::arch::asm!(
+		    "wrmsr",
+		    in("ecx") efer_msr,
+		    in("eax") efer_low,
+		    in("edx") efer_high,
+		    options(nostack, preserves_flags)
+		);
+	}
+
+	crate::info!("Syscall handling initialized");
+	Ok(())
+}

kernel/src/sysinfo.rs

@@ -0,0 +1,432 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! System information and hardware detection
+
+use alloc::{format, string::String, vec::Vec};
+
+use crate::error::Result;
+use crate::sync::Spinlock;
+
+/// CPU information structure
+#[derive(Debug, Clone)]
+pub struct CpuInfo {
+	pub vendor: String,
+	pub model_name: String,
+	pub family: u32,
+	pub model: u32,
+	pub stepping: u32,
+	pub features: Vec<String>,
+	pub cache_size: Option<usize>,
+	pub frequency: Option<u64>, // MHz
+	pub cores: u32,
+	pub threads: u32,
+}
+
+impl CpuInfo {
+	pub fn new() -> Self {
+		Self {
+			vendor: "Unknown".into(),
+			model_name: "Unknown CPU".into(),
+			family: 0,
+			model: 0,
+			stepping: 0,
+			features: Vec::new(),
+			cache_size: None,
+			frequency: None,
+			cores: 1,
+			threads: 1,
+		}
+	}
+
+	pub fn detect() -> Self {
+		let mut info = Self::new();
+
+		// Basic CPUID detection for x86_64
+		#[cfg(target_arch = "x86_64")]
+		{
+			info.detect_x86_64();
+		}
+
+		info
+	}
+
+	#[cfg(target_arch = "x86_64")]
+	fn detect_x86_64(&mut self) {
+		use core::arch::asm;
+
+		// Check if CPUID is supported
+		let mut eax: u32;
+		let mut ebx: u32 = 0;
+		let mut ecx: u32 = 0;
+		let mut edx: u32 = 0;
+
+		unsafe {
+			asm!("cpuid", inout("eax") 0 => eax, out("ecx") _, out("edx") _, options(preserves_flags));
+		}
+
+		if eax >= 1 {
+			// Get basic CPU info - avoid using ebx directly due to LLVM restrictions
+			unsafe {
+				asm!("mov {ebx_save}, rbx",
+                     "cpuid", 
+                     "mov {ebx_out:e}, ebx",
+                     "mov rbx, {ebx_save}",
+                     ebx_save = out(reg) _,
+                     ebx_out = out(reg) ebx,
+                     inout("eax") 1 => eax, 
+                     out("ecx") ecx, 
+                     out("edx") edx,
+                     options(preserves_flags));
+			}
+
+			self.family = ((eax >> 8) & 0xF) as u32;
+			self.model = ((eax >> 4) & 0xF) as u32;
+			self.stepping = (eax & 0xF) as u32;
+
+			// Detect features
+			if edx & (1 << 0) != 0 {
+				self.features.push("FPU".into());
+			}
+			if edx & (1 << 4) != 0 {
+				self.features.push("TSC".into());
+			}
+			if edx & (1 << 5) != 0 {
+				self.features.push("MSR".into());
+			}
+			if edx & (1 << 6) != 0 {
+				self.features.push("PAE".into());
+			}
+			if edx & (1 << 8) != 0 {
+				self.features.push("CX8".into());
+			}
+			if edx & (1 << 11) != 0 {
+				self.features.push("SEP".into());
+			}
+			if edx & (1 << 13) != 0 {
+				self.features.push("PGE".into());
+			}
+			if edx & (1 << 15) != 0 {
+				self.features.push("CMOV".into());
+			}
+			if edx & (1 << 23) != 0 {
+				self.features.push("MMX".into());
+			}
+			if edx & (1 << 25) != 0 {
+				self.features.push("SSE".into());
+			}
+			if edx & (1 << 26) != 0 {
+				self.features.push("SSE2".into());
+			}
+
+			if ecx & (1 << 0) != 0 {
+				self.features.push("SSE3".into());
+			}
+			if ecx & (1 << 9) != 0 {
+				self.features.push("SSSE3".into());
+			}
+			if ecx & (1 << 19) != 0 {
+				self.features.push("SSE4.1".into());
+			}
+			if ecx & (1 << 20) != 0 {
+				self.features.push("SSE4.2".into());
+			}
+			if ecx & (1 << 28) != 0 {
+				self.features.push("AVX".into());
+			}
+		}
+
+		// Try to get vendor string
+		unsafe {
+			let mut vendor_eax: u32;
+			let mut vendor_ebx: u32;
+			let mut vendor_ecx: u32;
+			let mut vendor_edx: u32;
+
+			asm!("mov {ebx_save}, rbx",
+                 "cpuid", 
+                 "mov {ebx_out:e}, ebx",
+                 "mov rbx, {ebx_save}",
+                 ebx_save = out(reg) _,
+                 ebx_out = out(reg) vendor_ebx,
+                 inout("eax") 0 => vendor_eax, 
+                 out("ecx") vendor_ecx, 
+                 out("edx") vendor_edx,
+                 options(preserves_flags));
+
+			if vendor_eax >= 0 {
+				let mut vendor_string = [0u8; 12];
+				vendor_string[0..4].copy_from_slice(&vendor_ebx.to_le_bytes());
+				vendor_string[4..8].copy_from_slice(&vendor_edx.to_le_bytes());
+				vendor_string[8..12].copy_from_slice(&vendor_ecx.to_le_bytes());
+
+				if let Ok(vendor) = core::str::from_utf8(&vendor_string) {
+					self.vendor = vendor.into();
+				}
+			}
+		}
+	}
+}
+
+/// Memory information
+#[derive(Debug, Clone)]
+pub struct MemoryInfo {
+	pub total_ram: usize,
+	pub available_ram: usize,
+	pub used_ram: usize,
+	pub kernel_memory: usize,
+	pub user_memory: usize,
+	pub cache_memory: usize,
+	pub swap_total: usize,
+	pub swap_used: usize,
+}
+
+impl MemoryInfo {
+	pub fn detect() -> Self {
+		let boot_info = unsafe { crate::boot::get_boot_info() };
+		let (total_pages, allocated_pages, free_pages) = crate::memory::page::stats();
+
+		let page_size = 4096; // 4KB pages
+		let total_ram = total_pages * page_size;
+		let used_ram = allocated_pages * page_size;
+		let available_ram = free_pages * page_size;
+
+		Self {
+			total_ram,
+			available_ram,
+			used_ram,
+			kernel_memory: used_ram, // Simplified for now
+			user_memory: 0,
+			cache_memory: 0,
+			swap_total: 0,
+			swap_used: 0,
+		}
+	}
+}
+
+/// System uptime and load information
+#[derive(Debug, Clone)]
+pub struct SystemStats {
+	pub uptime_seconds: u64,
+	pub boot_time: u64,
+	pub processes: u32,
+	pub threads: u32,
+	pub load_average: (f32, f32, f32), // 1min, 5min, 15min
+	pub context_switches: u64,
+	pub interrupts: u64,
+}
+
+impl SystemStats {
+	pub fn collect() -> Self {
+		let uptime = crate::time::get_jiffies().as_u64() / 1000; // Convert to seconds
+
+		// Collect performance counters
+		let context_switches =
+			crate::perf::perf_counter_get(crate::perf::CounterType::ContextSwitches)
+				.unwrap_or(0);
+		let interrupts =
+			crate::perf::perf_counter_get(crate::perf::CounterType::Interrupts)
+				.unwrap_or(0);
+
+		Self {
+			uptime_seconds: uptime,
+			boot_time: 0,                  // TODO: Get actual boot time
+			processes: 1,                  // TODO: Count actual processes
+			threads: 1,                    // TODO: Count actual threads
+			load_average: (0.0, 0.0, 0.0), // TODO: Calculate load average
+			context_switches,
+			interrupts,
+		}
+	}
+}
+
+/// Hardware device information
+#[derive(Debug, Clone)]
+pub struct DeviceInfo {
+	pub name: String,
+	pub device_type: String,
+	pub vendor: Option<String>,
+	pub device_id: Option<u32>,
+	pub driver: Option<String>,
+	pub status: String,
+}
+
+/// Complete system information
+#[derive(Debug)]
+pub struct SystemInfo {
+	pub kernel_version: String,
+	pub architecture: String,
+	pub cpu_info: CpuInfo,
+	pub memory_info: MemoryInfo,
+	pub system_stats: SystemStats,
+	pub devices: Vec<DeviceInfo>,
+}
+
+impl SystemInfo {
+	pub fn collect() -> Self {
+		Self {
+			kernel_version: format!("{} v{}", crate::NAME, crate::VERSION),
+			architecture: "x86_64".into(),
+			cpu_info: CpuInfo::detect(),
+			memory_info: MemoryInfo::detect(),
+			system_stats: SystemStats::collect(),
+			devices: Vec::new(), // TODO: Enumerate devices
+		}
+	}
+
+	pub fn format_detailed(&self) -> String {
+		let mut output = String::new();
+
+		output.push_str("System Information\n");
+		output.push_str("==================\n\n");
+
+		output.push_str(&format!("Kernel: {}\n", self.kernel_version));
+		output.push_str(&format!("Architecture: {}\n", self.architecture));
+		output.push_str(&format!(
+			"Uptime: {} seconds\n",
+			self.system_stats.uptime_seconds
+		));
+
+		output.push_str("\nCPU Information:\n");
+		output.push_str(&format!("  Vendor: {}\n", self.cpu_info.vendor));
+		output.push_str(&format!("  Model: {}\n", self.cpu_info.model_name));
+		output.push_str(&format!(
+			"  Family: {}, Model: {}, Stepping: {}\n",
+			self.cpu_info.family, self.cpu_info.model, self.cpu_info.stepping
+		));
+		output.push_str(&format!(
+			"  Cores: {}, Threads: {}\n",
+			self.cpu_info.cores, self.cpu_info.threads
+		));
+		if !self.cpu_info.features.is_empty() {
+			output.push_str(&format!(
+				"  Features: {}\n",
+				self.cpu_info.features.join(", ")
+			));
+		}
+
+		output.push_str("\nMemory Information:\n");
+		output.push_str(&format!(
+			"  Total RAM: {} KB\n",
+			self.memory_info.total_ram / 1024
+		));
+		output.push_str(&format!(
+			"  Available RAM: {} KB\n",
+			self.memory_info.available_ram / 1024
+		));
+		output.push_str(&format!(
+			"  Used RAM: {} KB\n",
+			self.memory_info.used_ram / 1024
+		));
+		output.push_str(&format!(
+			"  Kernel Memory: {} KB\n",
+			self.memory_info.kernel_memory / 1024
+		));
+
+		output.push_str("\nSystem Statistics:\n");
+		output.push_str(&format!("  Processes: {}\n", self.system_stats.processes));
+		output.push_str(&format!("  Threads: {}\n", self.system_stats.threads));
+		output.push_str(&format!(
+			"  Context Switches: {}\n",
+			self.system_stats.context_switches
+		));
+		output.push_str(&format!("  Interrupts: {}\n", self.system_stats.interrupts));
+
+		if !self.devices.is_empty() {
+			output.push_str("\nDevices:\n");
+			for device in &self.devices {
+				output.push_str(&format!(
+					"  {} ({}): {}\n",
+					device.name, device.device_type, device.status
+				));
+			}
+		}
+
+		output
+	}
+
+	pub fn format_compact(&self) -> String {
+		format!(
+			"{} {} - Uptime: {}s, RAM: {}/{} KB, CPU: {}",
+			self.kernel_version,
+			self.architecture,
+			self.system_stats.uptime_seconds,
+			self.memory_info.used_ram / 1024,
+			self.memory_info.total_ram / 1024,
+			self.cpu_info.vendor
+		)
+	}
+}
+
+/// Global system information cache
+static SYSTEM_INFO_CACHE: Spinlock<Option<SystemInfo>> = Spinlock::new(None);
+
+/// Initialize system information collection
+pub fn init_sysinfo() -> Result<()> {
+	let mut cache = SYSTEM_INFO_CACHE.lock();
+	*cache = Some(SystemInfo::collect());
+
+	crate::info!("System information collection initialized");
+	Ok(())
+}
+
+/// Get current system information (cached)
+pub fn get_system_info() -> SystemInfo {
+	let mut cache = SYSTEM_INFO_CACHE.lock();
+
+	// Refresh cache with current data
+	*cache = Some(SystemInfo::collect());
+
+	if let Some(ref info) = *cache {
+		// Create a copy since we can't return a reference
+		SystemInfo {
+			kernel_version: info.kernel_version.clone(),
+			architecture: info.architecture.clone(),
+			cpu_info: info.cpu_info.clone(),
+			memory_info: info.memory_info.clone(),
+			system_stats: info.system_stats.clone(),
+			devices: info.devices.clone(),
+		}
+	} else {
+		SystemInfo::collect()
+	}
+}
+
+/// Get formatted system information
+pub fn get_system_info_detailed() -> String {
+	let info = get_system_info();
+	info.format_detailed()
+}
+
+/// Get compact system information
+pub fn get_system_info_compact() -> String {
+	let info = get_system_info();
+	info.format_compact()
+}
+
+/// CPU benchmark utilities
+pub mod benchmark {
+	use super::*;
+
+	pub fn cpu_speed_test() -> u64 {
+		let start = crate::time::get_jiffies();
+
+		// Simple CPU-intensive operation
+		let mut result = 0u64;
+		for i in 0..1000000 {
+			result = result.wrapping_add(i * i);
+		}
+
+		let end = crate::time::get_jiffies();
+		let duration = (end - start).as_u64();
+
+		// Prevent optimization from removing the loop
+		core::hint::black_box(result);
+
+		duration
+	}
+
+	pub fn memory_speed_test() -> u64 {
+		// TODO: Implement memory speed test
+		0
+	}
+}

kernel/src/task.rs

@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Task management
+use crate::error::Result;
+
+pub struct Task;
+
+pub fn init() -> Result<()> {
+	Ok(())
+}

kernel/src/test_init.rs

@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Kernel initialization testing and validation
+
+use crate::error::Result;
+use crate::{error, info, warn};
+
+/// Test kernel subsystem initialization
+pub fn run_init_tests() -> Result<()> {
+	info!("Running kernel initialization tests");
+
+	// Test memory management
+	test_memory_management()?;
+
+	// Test interrupt handling
+	test_interrupt_handling()?;
+
+	// Test basic device operations
+	test_device_subsystem()?;
+
+	// Test scheduler
+	test_scheduler()?;
+
+	// Test filesystem
+	test_filesystem()?;
+
+	info!("All initialization tests passed");
+	Ok(())
+}
+
+/// Test memory management subsystem
+pub fn test_memory_management() -> Result<()> {
+	info!("Testing memory management...");
+
+	// Test basic allocation
+	let test_alloc = alloc::vec![1u8, 2, 3, 4, 5];
+	if test_alloc.len() != 5 {
+		return Err(crate::error::Error::Generic);
+	}
+
+	// Test page allocation
+	if let Ok(page) = crate::memory::page::alloc_page() {
+		crate::memory::page::free_page(page);
+		info!("Page allocation test passed");
+	} else {
+		warn!("Page allocation test failed - might not be implemented yet");
+	}
+
+	info!("Memory management tests completed");
+	Ok(())
+}
+
+/// Test interrupt handling
+fn test_interrupt_handling() -> Result<()> {
+	info!("Testing interrupt handling...");
+
+	// Test interrupt enable/disable
+	crate::interrupt::disable();
+	crate::interrupt::enable();
+
+	info!("Interrupt handling tests completed");
+	Ok(())
+}
+
+/// Test device subsystem
+fn test_device_subsystem() -> Result<()> {
+	info!("Testing device subsystem...");
+
+	// Test device registration (if implemented)
+	warn!("Device subsystem tests skipped - implementation pending");
+
+	Ok(())
+}
+
+/// Test scheduler
+fn test_scheduler() -> Result<()> {
+	info!("Testing scheduler...");
+
+	// Basic scheduler tests (if implemented)
+	warn!("Scheduler tests skipped - implementation pending");
+
+	Ok(())
+}
+
+/// Test filesystem
+fn test_filesystem() -> Result<()> {
+	info!("Testing filesystem...");
+
+	// Basic VFS tests (if implemented)
+	warn!("Filesystem tests skipped - implementation pending");
+
+	Ok(())
+}
+
+/// Display system information
+pub fn display_system_info() {
+	info!("=== System Information ===");
+
+	unsafe {
+		let boot_info = &crate::boot::BOOT_INFO;
+		info!("Memory size: {} bytes", boot_info.memory_size);
+		info!("Available memory: {} bytes", boot_info.available_memory);
+		info!("CPU count: {}", boot_info.cpu_count);
+
+		if let Some(ref cmdline) = boot_info.command_line {
+			info!("Command line: {}", cmdline);
+		}
+
+		if let Some(initrd_start) = boot_info.initrd_start {
+			info!("Initrd start: 0x{:x}", initrd_start);
+			if let Some(initrd_size) = boot_info.initrd_size {
+				info!("Initrd size: {} bytes", initrd_size);
+			}
+		}
+	}
+
+	info!("=========================");
+}
+
+/// Run basic functionality tests
+pub fn run_basic_tests() -> Result<()> {
+	info!("Running basic kernel functionality tests");
+
+	// Test string operations
+	let test_string = alloc::string::String::from("Hello Rust Kernel!");
+	if test_string.len() != 18 {
+		return Err(crate::error::Error::Generic);
+	}
+	info!("String operations test passed");
+
+	// Test vector operations
+	let mut test_vec = alloc::vec::Vec::new();
+	for i in 0..10 {
+		test_vec.push(i);
+	}
+	if test_vec.len() != 10 {
+		return Err(crate::error::Error::Generic);
+	}
+	info!("Vector operations test passed");
+
+	// Test basic arithmetic
+	let result = 42 * 42;
+	if result != 1764 {
+		return Err(crate::error::Error::Generic);
+	}
+	info!("Arithmetic operations test passed");
+
+	info!("All basic functionality tests passed");
+	Ok(())
+}

kernel/src/test_suite.rs

@@ -0,0 +1,660 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Comprehensive kernel test suite
+
+use alloc::string::{String, ToString};
+use alloc::vec::Vec;
+
+use crate::error::{Error, Result};
+
+/// Test result structure
+#[derive(Debug, Clone)]
+pub struct TestResult {
+	pub name: String,
+	pub passed: bool,
+	pub message: String,
+	pub duration_ms: u64,
+}
+
+/// Test suite statistics
+#[derive(Debug, Clone)]
+pub struct TestStats {
+	pub total_tests: u32,
+	pub passed_tests: u32,
+	pub failed_tests: u32,
+	pub total_duration_ms: u64,
+}
+
+/// Run all kernel tests
+pub fn run_all_tests() -> Result<TestStats> {
+	crate::info!("Starting comprehensive kernel test suite...");
+
+	let mut results = Vec::new();
+	let start_time = crate::time::get_time_ns();
+
+	// Memory management tests
+	results.extend(test_memory_management()?);
+
+	// Scheduler tests
+	results.extend(test_scheduler()?);
+
+	// IPC tests
+	results.extend(test_ipc()?);
+
+	// Performance monitoring tests
+	results.extend(test_performance_monitoring()?);
+
+	// File system tests
+	results.extend(test_filesystem()?);
+
+	// Hardware detection tests
+	results.extend(test_hardware_detection()?);
+
+	// Timer tests
+	results.extend(test_timer_functionality()?);
+
+	let end_time = crate::time::get_time_ns();
+	let total_duration = (end_time - start_time) / 1_000_000; // Convert to ms
+
+	// Calculate statistics
+	let stats = TestStats {
+		total_tests: results.len() as u32,
+		passed_tests: results.iter().filter(|r| r.passed).count() as u32,
+		failed_tests: results.iter().filter(|r| !r.passed).count() as u32,
+		total_duration_ms: total_duration,
+	};
+
+	// Print results summary
+	print_test_summary(&results, &stats);
+
+	Ok(stats)
+}
+
+/// Test memory management functionality
+fn test_memory_management() -> Result<Vec<TestResult>> {
+	let mut results = Vec::new();
+
+	// Test basic allocation
+	results.push(test_basic_allocation());
+
+	// Test advanced allocator stats
+	results.push(test_allocator_stats());
+
+	// Test heap operations
+	results.push(test_heap_operations());
+
+	Ok(results)
+}
+
+/// Test basic memory allocation
+fn test_basic_allocation() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		// Test kmalloc
+		let ptr = crate::memory::kmalloc::kmalloc(1024)?;
+		if ptr.is_null() {
+			return Err(crate::error::Error::ENOMEM);
+		}
+
+		// Test writing to allocated memory
+		unsafe {
+			core::ptr::write(ptr, 42u8);
+			let value = core::ptr::read(ptr);
+			if value != 42 {
+				return Err(crate::error::Error::EIO);
+			}
+		}
+
+		// Free memory
+		crate::memory::kmalloc::kfree(ptr);
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Basic Memory Allocation".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test allocator statistics
+fn test_allocator_stats() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let stats = crate::memory::advanced_allocator::get_memory_stats();
+
+		// Basic sanity checks
+		if stats.allocation_count < stats.active_allocations as u64 {
+			return Err(crate::error::Error::EIO);
+		}
+
+		if stats.peak_usage < stats.current_allocated {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Allocator Statistics".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Stats validation failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test heap operations
+fn test_heap_operations() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let initial_heap = crate::memory::get_heap_end();
+		let new_heap = crate::types::VirtAddr::new(initial_heap.as_usize() + 4096);
+
+		// Test heap expansion
+		crate::memory::set_heap_end(new_heap)?;
+
+		let current_heap = crate::memory::get_heap_end();
+		if current_heap != new_heap {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Heap Operations".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Heap operations failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test scheduler functionality
+fn test_scheduler() -> Result<Vec<TestResult>> {
+	let mut results = Vec::new();
+
+	results.push(test_scheduler_stats());
+	results.push(test_task_creation());
+
+	Ok(results)
+}
+
+/// Test scheduler statistics
+fn test_scheduler_stats() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let stats = crate::enhanced_scheduler::get_scheduler_stats();
+
+		// Basic validation
+		if stats.total_tasks < stats.runnable_tasks {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Scheduler Statistics".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Scheduler stats invalid".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test task creation
+fn test_task_creation() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let initial_count = crate::working_task::get_task_count();
+
+		// Create a test task
+		let _task_id =
+			crate::working_task::create_kernel_task("test_task", test_task_function)?;
+
+		let new_count = crate::working_task::get_task_count();
+		if new_count <= initial_count {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Task Creation".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Task creation failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test IPC functionality
+fn test_ipc() -> Result<Vec<TestResult>> {
+	let mut results = Vec::new();
+
+	results.push(test_ipc_stats());
+	results.push(test_message_queue());
+
+	Ok(results)
+}
+
+/// Test IPC statistics
+fn test_ipc_stats() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let stats = crate::ipc::get_ipc_stats();
+
+		// Basic validation - stats should be consistent
+		if stats.messages_sent < stats.messages_received && stats.messages_received > 0 {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "IPC Statistics".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"IPC stats invalid".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test message queue operations
+fn test_message_queue() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		// Create a message queue (simplified test)
+		let test_tid = crate::types::Tid(1);
+		let _queue_result = crate::ipc::create_message_queue(test_tid, 1024);
+
+		// Send a test message
+		let test_data = b"Hello, IPC!";
+		let sender_tid = crate::types::Tid(1);
+		let recipient_tid = crate::types::Tid(2);
+		let message_type = crate::ipc::MessageType::Data;
+		let data_vec = test_data.to_vec();
+		let _send_result = crate::ipc::send_message(
+			sender_tid,
+			recipient_tid,
+			message_type,
+			data_vec,
+			1,
+		);
+
+		// Try to receive the message
+		if let Ok(Some(_message)) = crate::ipc::receive_message(test_tid) {
+			Ok(())
+		} else {
+			Err(crate::error::Error::EIO)
+		}
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Message Queue Operations".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Message queue test failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test performance monitoring
+fn test_performance_monitoring() -> Result<Vec<TestResult>> {
+	let mut results = Vec::new();
+
+	results.push(test_perf_counters());
+	results.push(test_profiling());
+
+	Ok(results)
+}
+
+/// Test performance counters
+fn test_perf_counters() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let summary = crate::advanced_perf::get_performance_summary();
+
+		// Check if monitoring is enabled
+		if !summary.monitoring_enabled {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Performance Counters".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Performance monitoring disabled".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test profiling functionality
+fn test_profiling() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		// Start profiling for a test function
+		let _guard = crate::advanced_perf::profile_function("test_function");
+
+		// Do some work
+		for _i in 0..1000 {
+			unsafe { core::arch::asm!("nop") };
+		}
+
+		// Guard should automatically stop profiling when dropped
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Function Profiling".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Profiling failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test file system functionality
+fn test_filesystem() -> Result<Vec<TestResult>> {
+	let mut results = Vec::new();
+
+	results.push(test_fs_basic_ops());
+
+	Ok(results)
+}
+
+/// Test basic file system operations
+fn test_fs_basic_ops() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		// Test VFS initialization
+		let _vfs = crate::fs::get_root_fs()?;
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "File System Basic Operations".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"VFS operations failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test hardware detection
+fn test_hardware_detection() -> Result<Vec<TestResult>> {
+	let mut results = Vec::new();
+
+	results.push(test_cpu_detection());
+	results.push(test_memory_detection());
+
+	Ok(results)
+}
+
+/// Test CPU detection
+fn test_cpu_detection() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let cpu_info = crate::hardware::detect_cpu()?;
+
+		if cpu_info.vendor.is_empty() {
+			return Err(crate::error::Error::EIO);
+		}
+
+		if cpu_info.core_count == 0 {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "CPU Detection".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"CPU detection failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test memory detection
+fn test_memory_detection() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let memory_size = crate::hardware::detect_memory()?;
+
+		if memory_size < 16 * 1024 * 1024 {
+			// Less than 16MB seems wrong
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Memory Detection".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Memory detection failed".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test timer functionality
+fn test_timer_functionality() -> Result<Vec<TestResult>> {
+	let mut results = Vec::new();
+
+	results.push(test_timer_basic());
+	results.push(test_jiffies());
+
+	Ok(results)
+}
+
+/// Test basic timer functionality
+fn test_timer_basic() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let time1 = crate::time::get_time_ns();
+
+		// Do some work
+		for _i in 0..100 {
+			unsafe { core::arch::asm!("nop") };
+		}
+
+		let time2 = crate::time::get_time_ns();
+
+		if time2 <= time1 {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Timer Basic Functionality".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Timer not working".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test jiffies counter
+fn test_jiffies() -> TestResult {
+	let start = crate::time::get_time_ns();
+
+	let result = || -> Result<()> {
+		let jiffies1 = crate::time::get_jiffies();
+
+		// Wait a bit (simulate time passing)
+		for _i in 0..1000 {
+			unsafe { core::arch::asm!("nop") };
+		}
+
+		let jiffies2 = crate::time::get_jiffies();
+
+		// Jiffies should either be the same or have incremented
+		if jiffies2.0 < jiffies1.0 {
+			return Err(crate::error::Error::EIO);
+		}
+
+		Ok(())
+	}();
+
+	let end = crate::time::get_time_ns();
+	let duration = (end - start) / 1_000_000;
+
+	TestResult {
+		name: "Jiffies Counter".to_string(),
+		passed: result.is_ok(),
+		message: if result.is_ok() {
+			"Passed".to_string()
+		} else {
+			"Jiffies counter broken".to_string()
+		},
+		duration_ms: duration,
+	}
+}
+
+/// Test task function for task creation test
+fn test_task_function() {
+	// Simple test task that does nothing
+	crate::info!("Test task executing");
+}
+
+/// Print test results summary
+fn print_test_summary(results: &[TestResult], stats: &TestStats) {
+	crate::info!("=== KERNEL TEST SUITE RESULTS ===");
+	crate::info!("Total tests: {}", stats.total_tests);
+	crate::info!("Passed: {}", stats.passed_tests);
+	crate::info!("Failed: {}", stats.failed_tests);
+	crate::info!(
+		"Success rate: {:.1}%",
+		(stats.passed_tests as f32 / stats.total_tests as f32) * 100.0
+	);
+	crate::info!("Total duration: {} ms", stats.total_duration_ms);
+
+	if stats.failed_tests > 0 {
+		crate::info!("Failed tests:");
+		for result in results {
+			if !result.passed {
+				crate::info!(
+					"  - {} ({}ms): {}",
+					result.name,
+					result.duration_ms,
+					result.message
+				);
+			}
+		}
+	}
+
+	crate::info!("=== END TEST RESULTS ===");
+}
+
+/// Initialize test suite
+pub fn init() -> Result<()> {
+	crate::info!("Kernel test suite initialized");
+	Ok(())
+}

kernel/src/time.rs

@@ -0,0 +1,507 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Time management compatible with Linux kernel
+
+use alloc::vec::Vec;
+use core::sync::atomic::{AtomicU64, Ordering};
+
+use crate::error::Result;
+use crate::types::Jiffies; // Add Vec import
+
+/// System clock frequency (Hz) - typically 1000 for 1ms ticks
+pub const HZ: u64 = 1000;
+
+/// Nanoseconds per second
+pub const NSEC_PER_SEC: u64 = 1_000_000_000;
+
+/// Nanoseconds per millisecond
+pub const NSEC_PER_MSEC: u64 = 1_000_000;
+
+/// Nanoseconds per microsecond
+pub const NSEC_PER_USEC: u64 = 1_000;
+
+/// Nanoseconds per jiffy
+pub const NSEC_PER_JIFFY: u64 = NSEC_PER_SEC / HZ;
+
+/// Global time counters
+static JIFFIES_COUNTER: AtomicU64 = AtomicU64::new(0);
+static BOOTTIME_NS: AtomicU64 = AtomicU64::new(0);
+
+/// TSC (Time Stamp Counter) related globals
+pub static TSC_FREQUENCY: AtomicU64 = AtomicU64::new(0);
+static BOOT_TSC: AtomicU64 = AtomicU64::new(0);
+
+/// Time structure - Linux compatible
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct TimeSpec {
+	pub tv_sec: i64,
+	pub tv_nsec: i64,
+}
+
+impl TimeSpec {
+	pub const fn new(sec: i64, nsec: i64) -> Self {
+		Self {
+			tv_sec: sec,
+			tv_nsec: nsec,
+		}
+	}
+
+	pub fn zero() -> Self {
+		Self::new(0, 0)
+	}
+
+	pub fn to_ns(&self) -> u64 {
+		(self.tv_sec as u64 * NSEC_PER_SEC) + self.tv_nsec as u64
+	}
+
+	pub fn from_ns(ns: u64) -> Self {
+		let sec = (ns / NSEC_PER_SEC) as i64;
+		let nsec = (ns % NSEC_PER_SEC) as i64;
+		Self::new(sec, nsec)
+	}
+}
+
+/// Get current system time
+pub fn get_current_time() -> TimeSpec {
+	// In a real implementation, this would read from a real-time clock
+	// For now, we'll use the boot time plus jiffies
+	let boot_ns = BOOTTIME_NS.load(Ordering::Relaxed);
+	let jiffies = get_jiffies();
+	let current_ns = boot_ns + (jiffies * NSEC_PER_JIFFY);
+	TimeSpec::from_ns(current_ns)
+}
+
+/// High resolution timer structure
+#[derive(Debug, Clone)]
+pub struct HrTimer {
+	pub expires: TimeSpec,
+	pub function: Option<fn()>,
+	pub base: HrTimerBase,
+}
+
+/// Timer bases - Linux compatible
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum HrTimerBase {
+	Monotonic,
+	Realtime,
+	Boottime,
+	Tai,
+}
+
+impl HrTimer {
+	pub fn new(base: HrTimerBase) -> Self {
+		Self {
+			expires: TimeSpec::zero(),
+			function: None,
+			base,
+		}
+	}
+
+	pub fn set_expires(&mut self, expires: TimeSpec) {
+		self.expires = expires;
+	}
+
+	pub fn set_function(&mut self, function: fn()) {
+		self.function = Some(function);
+	}
+
+	pub fn is_expired(&self) -> bool {
+		let now = match self.base {
+			HrTimerBase::Monotonic => monotonic_time(),
+			HrTimerBase::Realtime => get_realtime(),
+			HrTimerBase::Boottime => get_boottime(),
+			HrTimerBase::Tai => get_realtime(), // Simplified
+		};
+		now >= self.expires
+	}
+}
+
+/// Initialize time management
+pub fn init() -> Result<()> {
+	// Initialize system clocks
+	let boot_time = read_hardware_clock();
+	BOOTTIME_NS.store(boot_time, Ordering::Relaxed);
+
+	// Set up timer interrupts through our timer module
+	crate::timer::init_timer()?;
+
+	// Initialize high-resolution timers
+	init_high_res_timers()?;
+
+	crate::info!("Time management initialized, boot time: {} ns", boot_time);
+	Ok(())
+}
+
+/// Initialize high-resolution timers
+fn init_high_res_timers() -> Result<()> {
+	// Initialize TSC (Time Stamp Counter) frequency detection
+	let tsc_freq = detect_tsc_frequency();
+	TSC_FREQUENCY.store(tsc_freq, Ordering::Relaxed);
+
+	// Store initial TSC value for relative timing
+	BOOT_TSC.store(read_tsc(), Ordering::Relaxed);
+
+	crate::info!(
+		"High-resolution timers initialized, TSC frequency: {} Hz",
+		tsc_freq
+	);
+	Ok(())
+}
+
+/// Detect TSC frequency using PIT calibration
+fn detect_tsc_frequency() -> u64 {
+	// Calibrate TSC against PIT (Programmable Interval Timer)
+	// This is a simplified implementation
+
+	unsafe {
+		// Set PIT to mode 2 (rate generator) with a known frequency
+		crate::arch::x86_64::port::outb(0x43, 0x34); // Channel 0, mode 2
+
+		// Set frequency to ~1193 Hz (divisor = 1000)
+		let divisor = 1000u16;
+		crate::arch::x86_64::port::outb(0x40, (divisor & 0xFF) as u8);
+		crate::arch::x86_64::port::outb(0x40, (divisor >> 8) as u8);
+
+		// Read initial TSC
+		let tsc_start = read_tsc();
+
+		// Wait for a PIT tick (simplified timing)
+		let mut last_pit = read_pit_count();
+		let mut pit_ticks = 0;
+
+		while pit_ticks < 10 {
+			// Wait for ~10ms
+			let current_pit = read_pit_count();
+			if current_pit != last_pit {
+				pit_ticks += 1;
+				last_pit = current_pit;
+			}
+		}
+
+		// Read final TSC
+		let tsc_end = read_tsc();
+		let tsc_delta = tsc_end - tsc_start;
+
+		// Calculate frequency (rough approximation)
+		// 10 PIT ticks at ~1193 Hz = ~8.4ms
+		let frequency = (tsc_delta * 1193) / 10;
+
+		// Reasonable bounds checking
+		if frequency < 100_000_000 || frequency > 10_000_000_000 {
+			// Default to 2.4 GHz if calibration seems wrong
+			2_400_000_000
+		} else {
+			frequency
+		}
+	}
+}
+
+/// Read PIT counter value
+unsafe fn read_pit_count() -> u16 {
+	crate::arch::x86_64::port::outb(0x43, 0x00); // Latch counter 0
+	let low = crate::arch::x86_64::port::inb(0x40) as u16;
+	let high = crate::arch::x86_64::port::inb(0x40) as u16;
+	(high << 8) | low
+}
+
+/// Initialize time management subsystem
+pub fn init_time() -> Result<()> {
+	// Initialize the timer wheel
+	let _timer_wheel = get_timer_wheel();
+
+	// Set initial boot time (in a real implementation, this would read from RTC)
+	BOOTTIME_NS.store(0, Ordering::Relaxed);
+
+	// Reset jiffies counter
+	JIFFIES_COUNTER.store(0, Ordering::Relaxed);
+
+	crate::info!("Time management initialized");
+	Ok(())
+}
+
+/// Read hardware clock implementation
+fn read_hardware_clock() -> u64 {
+	// Read from CMOS RTC (Real Time Clock)
+	// This is a simplified implementation
+	unsafe {
+		// Disable NMI and read seconds
+		crate::arch::x86_64::port::outb(0x70, 0x00);
+		let seconds = crate::arch::x86_64::port::inb(0x71);
+
+		// Read minutes
+		crate::arch::x86_64::port::outb(0x70, 0x02);
+		let minutes = crate::arch::x86_64::port::inb(0x71);
+
+		// Read hours
+		crate::arch::x86_64::port::outb(0x70, 0x04);
+		let hours = crate::arch::x86_64::port::inb(0x71);
+
+		// Convert BCD to binary if needed (simplified)
+		let sec = bcd_to_bin(seconds);
+		let min = bcd_to_bin(minutes);
+		let hr = bcd_to_bin(hours);
+
+		// Convert to nanoseconds since epoch (simplified calculation)
+		let total_seconds = (hr as u64 * 3600) + (min as u64 * 60) + sec as u64;
+		total_seconds * 1_000_000_000 // Convert to nanoseconds
+	}
+}
+
+/// Convert BCD to binary
+fn bcd_to_bin(bcd: u8) -> u8 {
+	((bcd >> 4) * 10) + (bcd & 0x0F)
+}
+
+/// Get current jiffies count
+pub fn get_jiffies() -> Jiffies {
+	Jiffies(JIFFIES_COUNTER.load(Ordering::Relaxed))
+}
+
+/// Increment jiffies counter (called from timer interrupt)
+pub fn update_jiffies() {
+	JIFFIES_COUNTER.fetch_add(1, Ordering::Relaxed);
+}
+
+/// Get current time in nanoseconds since boot
+pub fn get_time_ns() -> u64 {
+	// Use TSC for high-resolution timing
+	let tsc_freq = TSC_FREQUENCY.load(Ordering::Relaxed);
+	if tsc_freq > 0 {
+		let tsc = read_tsc();
+		let boot_tsc = BOOT_TSC.load(Ordering::Relaxed);
+		if tsc >= boot_tsc {
+			((tsc - boot_tsc) * 1_000_000_000) / tsc_freq
+		} else {
+			// Handle TSC overflow (rare)
+			get_jiffies().0 * NSEC_PER_JIFFY
+		}
+	} else {
+		// Fallback to jiffies-based timing
+		get_jiffies().0 * NSEC_PER_JIFFY
+	}
+}
+
+/// Get high resolution time
+pub fn ktime_get() -> TimeSpec {
+	let ns = get_time_ns();
+	TimeSpec {
+		tv_sec: (ns / 1_000_000_000) as i64,
+		tv_nsec: (ns % 1_000_000_000) as i64,
+	}
+}
+
+/// Read Time Stamp Counter
+fn read_tsc() -> u64 {
+	unsafe {
+		let low: u32;
+		let high: u32;
+		core::arch::asm!(
+		    "rdtsc",
+		    out("eax") low,
+		    out("edx") high,
+		    options(nomem, nostack, preserves_flags)
+		);
+		((high as u64) << 32) | (low as u64)
+	}
+}
+
+/// Get monotonic time (time since boot)
+pub fn monotonic_time() -> TimeSpec {
+	let jiffies = get_jiffies();
+	let ns = jiffies.0 * NSEC_PER_JIFFY;
+	TimeSpec::from_ns(ns)
+}
+
+/// Get boot time
+pub fn get_boottime() -> TimeSpec {
+	let boot_ns = BOOTTIME_NS.load(Ordering::Relaxed);
+	let current_ns = get_time_ns();
+	TimeSpec::from_ns(boot_ns + current_ns)
+}
+
+/// Get real time (wall clock time)
+pub fn get_realtime() -> TimeSpec {
+	get_boottime()
+}
+
+/// Convert nanoseconds to jiffies
+pub fn ns_to_jiffies(ns: u64) -> Jiffies {
+	Jiffies(ns / NSEC_PER_JIFFY)
+}
+
+/// Convert jiffies to nanoseconds
+pub fn jiffies_to_ns(jiffies: Jiffies) -> u64 {
+	jiffies.0 * NSEC_PER_JIFFY
+}
+
+/// Convert milliseconds to jiffies
+pub fn msecs_to_jiffies(ms: u64) -> Jiffies {
+	ns_to_jiffies(ms * NSEC_PER_MSEC)
+}
+
+/// Convert jiffies to milliseconds
+pub fn jiffies_to_msecs(jiffies: Jiffies) -> u64 {
+	jiffies_to_ns(jiffies) / NSEC_PER_MSEC
+}
+
+/// Convert microseconds to jiffies
+pub fn usecs_to_jiffies(us: u64) -> Jiffies {
+	ns_to_jiffies(us * NSEC_PER_USEC)
+}
+
+/// Convert jiffies to microseconds
+pub fn jiffies_to_usecs(jiffies: Jiffies) -> u64 {
+	jiffies_to_ns(jiffies) / NSEC_PER_USEC
+}
+
+/// Sleep functions - Linux compatible
+pub fn msleep(ms: u64) {
+	let target_jiffies = get_jiffies().0 + msecs_to_jiffies(ms).0;
+	while get_jiffies().0 < target_jiffies {
+		crate::scheduler::yield_now();
+	}
+}
+
+pub fn usleep_range(min_us: u64, max_us: u64) {
+	let us = (min_us + max_us) / 2; // Use average
+	let target_jiffies = get_jiffies().0 + usecs_to_jiffies(us).0;
+	while get_jiffies().0 < target_jiffies {
+		crate::scheduler::yield_now();
+	}
+}
+
+pub fn ndelay(ns: u64) {
+	// Busy wait for nanoseconds (not recommended for long delays)
+	let start = get_time_ns();
+	while get_time_ns() - start < ns {
+		core::hint::spin_loop();
+	}
+}
+
+pub fn udelay(us: u64) {
+	ndelay(us * NSEC_PER_USEC);
+}
+
+pub fn mdelay(ms: u64) {
+	ndelay(ms * NSEC_PER_MSEC);
+}
+
+/// Timer wheel for managing timers
+#[derive(Debug)]
+pub struct TimerWheel {
+	levels: [Vec<HrTimer>; 8], // Multiple levels for different time ranges
+	current_jiffies: u64,
+}
+
+impl TimerWheel {
+	pub fn new() -> Self {
+		const EMPTY_VEC: Vec<HrTimer> = Vec::new();
+		Self {
+			levels: [EMPTY_VEC; 8],
+			current_jiffies: 0,
+		}
+	}
+
+	pub fn add_timer(&mut self, timer: HrTimer) {
+		let now_ns = get_time_ns();
+		let expires_ns = timer.expires.to_ns();
+
+		// If already expired or expires very soon, put in level 0
+		if expires_ns <= now_ns {
+			self.levels[0].push(timer);
+			return;
+		}
+
+		let delta_ns = expires_ns - now_ns;
+		let delta_jiffies = delta_ns / NSEC_PER_JIFFY;
+
+		// Determine level based on delta
+		// Level 0: Immediate to ~256ms
+		// Level 1: ~256ms to ~16s
+		// Level 2: ~16s to ~17m
+		// Level 3: ~17m to ~18h
+		// Level 4+: Far future
+		let level = if delta_jiffies < 256 {
+			0
+		} else if delta_jiffies < 256 * 64 {
+			1
+		} else if delta_jiffies < 256 * 64 * 64 {
+			2
+		} else if delta_jiffies < 256 * 64 * 64 * 64 {
+			3
+		} else {
+			4
+		};
+
+		let level = core::cmp::min(level, 7);
+		self.levels[level].push(timer);
+	}
+
+	pub fn run_timers(&mut self) {
+		self.current_jiffies = get_jiffies().0;
+
+		// Check and run expired timers
+		for level in &mut self.levels {
+			level.retain(|timer| {
+				if timer.is_expired() {
+					if let Some(function) = timer.function {
+						function();
+					}
+					false // Remove expired timer
+				} else {
+					true // Keep timer
+				}
+			});
+		}
+	}
+}
+
+use core::sync::atomic::AtomicBool;
+
+/// Global timer wheel
+use crate::sync::Spinlock;
+
+static TIMER_WHEEL_INIT: AtomicBool = AtomicBool::new(false);
+static mut TIMER_WHEEL_STORAGE: Option<Spinlock<TimerWheel>> = None;
+
+fn get_timer_wheel() -> &'static Spinlock<TimerWheel> {
+	if !TIMER_WHEEL_INIT.load(Ordering::Acquire) {
+		// Initialize timer wheel
+		let wheel = TimerWheel::new();
+		unsafe {
+			TIMER_WHEEL_STORAGE = Some(Spinlock::new(wheel));
+		}
+		TIMER_WHEEL_INIT.store(true, Ordering::Release);
+	}
+
+	#[allow(static_mut_refs)]
+	unsafe {
+		TIMER_WHEEL_STORAGE.as_ref().unwrap()
+	}
+}
+
+/// Add a timer to the system
+pub fn add_timer(timer: HrTimer) {
+	let timer_wheel = get_timer_wheel();
+	let mut wheel = timer_wheel.lock();
+	wheel.add_timer(timer);
+}
+
+/// Run expired timers (called from timer interrupt)
+pub fn run_timers() {
+	let timer_wheel = get_timer_wheel();
+	let mut wheel = timer_wheel.lock();
+	wheel.run_timers();
+}
+
+/// Timer interrupt handler
+pub fn timer_interrupt() {
+	// Update jiffies
+	update_jiffies();
+
+	// Run expired timers
+	run_timers();
+
+	// Update scheduler tick
+	crate::scheduler::scheduler_tick();
+}

kernel/src/timer.rs

@@ -0,0 +1,251 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Timer interrupt handler for preemptive scheduling
+
+use core::sync::atomic::{AtomicBool, AtomicU64, Ordering};
+
+use crate::enhanced_scheduler;
+use crate::sync::Spinlock;
+use crate::time::get_jiffies;
+use crate::types::Jiffies;
+
+/// Timer frequency (Hz) - how often timer interrupt fires
+const TIMER_FREQUENCY: u64 = 1000; // 1000 Hz = 1ms intervals
+
+/// Scheduler quantum (time slice) in timer ticks
+const SCHEDULER_QUANTUM: u64 = 10; // 10ms default quantum
+
+/// Timer statistics
+#[derive(Debug, Clone)]
+pub struct TimerStats {
+	pub total_interrupts: u64,
+	pub scheduler_invocations: u64,
+	pub context_switches: u64,
+	pub last_update: Jiffies,
+}
+
+/// Global timer state
+pub struct TimerState {
+	tick_count: AtomicU64,
+	last_schedule_tick: AtomicU64,
+	preemption_enabled: AtomicBool,
+	stats: Spinlock<TimerStats>,
+}
+
+impl TimerState {
+	const fn new() -> Self {
+		Self {
+			tick_count: AtomicU64::new(0),
+			last_schedule_tick: AtomicU64::new(0),
+			preemption_enabled: AtomicBool::new(true),
+			stats: Spinlock::new(TimerStats {
+				total_interrupts: 0,
+				scheduler_invocations: 0,
+				context_switches: 0,
+				last_update: Jiffies(0),
+			}),
+		}
+	}
+
+	/// Handle timer interrupt
+	pub fn handle_timer_interrupt(&self) {
+		let current_tick = self.tick_count.fetch_add(1, Ordering::SeqCst);
+		let last_schedule = self.last_schedule_tick.load(Ordering::SeqCst);
+
+		// Update statistics
+		{
+			let mut stats = self.stats.lock();
+			stats.total_interrupts += 1;
+			stats.last_update = get_jiffies();
+		}
+
+		// Check if we should invoke the scheduler
+		if self.preemption_enabled.load(Ordering::SeqCst) {
+			let ticks_since_schedule = current_tick - last_schedule;
+
+			if ticks_since_schedule >= SCHEDULER_QUANTUM {
+				self.invoke_scheduler();
+				self.last_schedule_tick
+					.store(current_tick, Ordering::SeqCst);
+			}
+		}
+
+		// Update current task runtime
+		enhanced_scheduler::update_current_task_runtime(1);
+	}
+
+	/// Invoke the scheduler for preemptive multitasking
+	fn invoke_scheduler(&self) {
+		// Update statistics
+		{
+			let mut stats = self.stats.lock();
+			stats.scheduler_invocations += 1;
+		}
+
+		// Get next task to run
+		if let Some(next_tid) = enhanced_scheduler::schedule_next() {
+			let current_tid = enhanced_scheduler::get_current_task();
+
+			// Only switch if different task
+			if current_tid != Some(next_tid) {
+				if let Ok(()) = enhanced_scheduler::switch_to_task(next_tid) {
+					// Update context switch statistics
+					let mut stats = self.stats.lock();
+					stats.context_switches += 1;
+
+					// Perform actual context switch
+					// This will save current CPU state and restore the state of the next task
+					crate::scheduler::context_switch_to(next_tid);
+
+					crate::info!(
+						"Context switch: {:?} -> {:?}",
+						current_tid,
+						next_tid
+					);
+				}
+			}
+		}
+	}
+
+	/// Enable or disable preemption
+	pub fn set_preemption_enabled(&self, enabled: bool) {
+		self.preemption_enabled.store(enabled, Ordering::SeqCst);
+		enhanced_scheduler::set_preemption_enabled(enabled);
+	}
+
+	/// Get timer statistics
+	pub fn get_stats(&self) -> TimerStats {
+		self.stats.lock().clone()
+	}
+
+	/// Get current tick count
+	pub fn get_tick_count(&self) -> u64 {
+		self.tick_count.load(Ordering::SeqCst)
+	}
+
+	/// Reset statistics
+	pub fn reset_stats(&self) {
+		let mut stats = self.stats.lock();
+		stats.total_interrupts = 0;
+		stats.scheduler_invocations = 0;
+		stats.context_switches = 0;
+		stats.last_update = get_jiffies();
+	}
+
+	/// Check if preemption is enabled
+	pub fn is_preemption_enabled(&self) -> bool {
+		self.preemption_enabled.load(Ordering::SeqCst)
+	}
+}
+
+/// Timer interrupt counter
+static TIMER_INTERRUPTS: AtomicU64 = AtomicU64::new(0);
+
+/// Get timer interrupt count
+pub fn get_timer_interrupts() -> u64 {
+	TIMER_INTERRUPTS.load(Ordering::Relaxed)
+}
+
+/// Increment timer interrupt counter
+pub fn increment_timer_interrupts() {
+	TIMER_INTERRUPTS.fetch_add(1, Ordering::Relaxed);
+}
+
+/// Global timer state
+static TIMER_STATE: TimerState = TimerState::new();
+
+/// Initialize timer for preemptive scheduling
+pub fn init_timer() -> crate::error::Result<()> {
+	// Initialize the Programmable Interval Timer (PIT)
+	init_pit(TIMER_FREQUENCY)?;
+
+	// Enable timer interrupts
+	crate::arch::x86_64::idt::register_timer_handler(timer_interrupt_handler);
+
+	crate::info!(
+		"Timer initialized for preemptive scheduling ({}Hz)",
+		TIMER_FREQUENCY
+	);
+	Ok(())
+}
+
+/// Timer interrupt handler (called from IDT)
+pub extern "C" fn timer_interrupt_handler() {
+	TIMER_STATE.handle_timer_interrupt();
+	increment_timer_interrupts();
+
+	// Send EOI to PIC
+	unsafe {
+		crate::arch::x86_64::pic::send_eoi(0); // Timer is IRQ 0
+	}
+}
+
+/// Initialize Programmable Interval Timer (PIT)
+fn init_pit(frequency: u64) -> crate::error::Result<()> {
+	use crate::arch::x86_64::port::Port;
+
+	// PIT frequency is 1.193182 MHz
+	const PIT_FREQUENCY: u64 = 1193182;
+
+	// Calculate divisor for desired frequency
+	let divisor = PIT_FREQUENCY / frequency;
+	if divisor > 65535 {
+		return Err(crate::error::Error::InvalidArgument);
+	}
+
+	unsafe {
+		// Configure PIT channel 0 for periodic mode
+		let mut cmd_port = Port::new(0x43);
+		let mut data_port = Port::new(0x40);
+
+		// Command: Channel 0, Access mode lobyte/hibyte, Mode 2 (rate generator)
+		cmd_port.write(0x34u32);
+
+		// Set divisor (low byte first, then high byte)
+		data_port.write((divisor & 0xFF) as u32);
+		data_port.write((divisor >> 8) as u32);
+	}
+
+	Ok(())
+}
+
+/// Get timer statistics
+pub fn get_timer_stats() -> TimerStats {
+	TIMER_STATE.get_stats()
+}
+
+/// Enable/disable preemptive scheduling
+pub fn set_preemption_enabled(enabled: bool) {
+	TIMER_STATE.set_preemption_enabled(enabled);
+}
+
+/// Get current timer tick count
+pub fn get_timer_ticks() -> u64 {
+	TIMER_STATE.get_tick_count()
+}
+
+/// Reset timer statistics
+pub fn reset_timer_stats() {
+	TIMER_STATE.reset_stats();
+}
+
+/// Sleep for specified number of timer ticks
+pub fn sleep_ticks(ticks: u64) -> crate::error::Result<()> {
+	enhanced_scheduler::sleep_current_task(ticks)
+}
+
+/// Yield current task to scheduler
+pub fn yield_task() {
+	TIMER_STATE.invoke_scheduler();
+}
+
+/// Handle timer tick - called from kernel loops for timing updates
+pub fn handle_timer_tick() {
+	// Update timer statistics
+	TIMER_STATE.handle_timer_interrupt();
+
+	// Trigger scheduler if preemption is enabled
+	if TIMER_STATE.is_preemption_enabled() {
+		yield_task();
+	}
+}

kernel/src/types.rs

@@ -0,0 +1,206 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Common kernel types
+
+use core::fmt;
+use core::ops::{Add, Mul, Sub};
+
+/// Process ID type
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Pid(pub u32);
+
+impl fmt::Display for Pid {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		write!(f, "{}", self.0)
+	}
+}
+
+/// Thread ID type
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Tid(pub u32);
+
+impl fmt::Display for Tid {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		write!(f, "{}", self.0)
+	}
+}
+
+/// User ID type
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Uid(pub u32);
+
+/// Group ID type  
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Gid(pub u32);
+
+/// Physical address type
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct PhysAddr(pub usize);
+
+impl PhysAddr {
+	pub const fn new(addr: usize) -> Self {
+		Self(addr)
+	}
+
+	pub const fn as_u64(self) -> u64 {
+		self.0 as u64
+	}
+
+	pub const fn as_usize(self) -> usize {
+		self.0
+	}
+}
+
+impl Add<usize> for PhysAddr {
+	type Output = Self;
+
+	fn add(self, rhs: usize) -> Self::Output {
+		Self(self.0 + rhs)
+	}
+}
+
+impl Sub<usize> for PhysAddr {
+	type Output = Self;
+
+	fn sub(self, rhs: usize) -> Self::Output {
+		Self(self.0 - rhs)
+	}
+}
+
+/// Virtual address type
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct VirtAddr(pub usize);
+
+impl VirtAddr {
+	pub const fn new(addr: usize) -> Self {
+		Self(addr)
+	}
+
+	pub const fn as_u64(self) -> u64 {
+		self.0 as u64
+	}
+
+	pub const fn as_usize(self) -> usize {
+		self.0
+	}
+
+	pub const fn as_ptr<T>(self) -> *const T {
+		self.0 as *const T
+	}
+
+	pub const fn as_mut_ptr<T>(self) -> *mut T {
+		self.0 as *mut T
+	}
+}
+
+impl Add<usize> for VirtAddr {
+	type Output = Self;
+
+	fn add(self, rhs: usize) -> Self::Output {
+		Self(self.0 + rhs)
+	}
+}
+
+impl Sub<usize> for VirtAddr {
+	type Output = Self;
+
+	fn sub(self, rhs: usize) -> Self::Output {
+		Self(self.0 - rhs)
+	}
+}
+
+impl Sub<VirtAddr> for VirtAddr {
+	type Output = usize;
+
+	fn sub(self, rhs: VirtAddr) -> Self::Output {
+		self.0 - rhs.0
+	}
+}
+
+impl fmt::Display for VirtAddr {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		write!(f, "0x{:x}", self.0)
+	}
+}
+
+/// Page size constants
+pub const PAGE_SIZE: usize = 4096;
+pub const PAGE_SHIFT: usize = 12;
+
+/// Page frame number
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Pfn(pub usize);
+
+impl Pfn {
+	pub fn from_phys_addr(addr: PhysAddr) -> Self {
+		Self(addr.0 >> PAGE_SHIFT)
+	}
+
+	pub fn to_phys_addr(self) -> PhysAddr {
+		PhysAddr(self.0 << PAGE_SHIFT)
+	}
+}
+
+/// CPU number type
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct CpuId(pub u32);
+
+/// IRQ number type
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Irq(pub u32);
+
+/// Time types
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Jiffies(pub u64);
+
+impl Jiffies {
+	pub fn as_u64(self) -> u64 {
+		self.0
+	}
+}
+
+impl Mul<u64> for Jiffies {
+	type Output = u64;
+
+	fn mul(self, rhs: u64) -> Self::Output {
+		self.0 * rhs
+	}
+}
+
+impl core::ops::Add<u64> for Jiffies {
+	type Output = Jiffies;
+
+	fn add(self, rhs: u64) -> Self::Output {
+		Jiffies(self.0 + rhs)
+	}
+}
+
+impl core::ops::Sub<Jiffies> for Jiffies {
+	type Output = Jiffies;
+
+	fn sub(self, rhs: Jiffies) -> Self::Output {
+		Jiffies(self.0.saturating_sub(rhs.0))
+	}
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Nanoseconds(pub u64);
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Microseconds(pub u64);
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Milliseconds(pub u64);
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Seconds(pub u64);
+
+/// Device ID type
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct DeviceId(pub u32);
+
+impl fmt::Display for DeviceId {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		write!(f, "{}", self.0)
+	}
+}

kernel/src/usermode.rs

@@ -0,0 +1,368 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! User mode program support
+
+use alloc::{boxed::Box, string::String, vec, vec::Vec};
+
+use crate::arch::x86_64::context::Context;
+use crate::error::{Error, Result};
+use crate::memory::{PageFlags, PhysAddr, VirtAddr};
+use crate::process::{Process, ProcessState, Thread};
+use crate::types::{Gid, Uid};
+
+/// User mode privilege level
+pub const USER_CS: u16 = 0x1B; // GDT selector for user code segment
+pub const USER_DS: u16 = 0x23; // GDT selector for user data segment
+
+/// User mode stack size
+pub const USER_STACK_SIZE: usize = 8 * 1024 * 1024; // 8MB stack
+
+/// User mode heap start address
+pub const USER_HEAP_START: u64 = 0x40000000; // 1GB
+
+/// Simple ELF header for user programs
+#[repr(C)]
+#[derive(Debug, Clone)]
+pub struct SimpleElfHeader {
+	pub magic: [u8; 4],
+	pub class: u8,               // 32-bit or 64-bit
+	pub data: u8,                // Endianness
+	pub version: u8,             // ELF version
+	pub entry: u64,              // Entry point
+	pub program_offset: u64,     // Program header offset
+	pub section_offset: u64,     // Section header offset
+	pub flags: u32,              // Architecture-specific flags
+	pub header_size: u16,        // ELF header size
+	pub program_entry_size: u16, // Program header entry size
+	pub program_count: u16,      // Number of program headers
+	pub section_entry_size: u16, // Section header entry size
+	pub section_count: u16,      // Number of section headers
+	pub section_names: u16,      // Section header string table index
+}
+
+/// Simple program header
+#[repr(C)]
+#[derive(Debug, Clone)]
+pub struct ProgramHeader {
+	pub type_: u32,  // Segment type
+	pub flags: u32,  // Segment flags
+	pub offset: u64, // Offset in file
+	pub vaddr: u64,  // Virtual address
+	pub paddr: u64,  // Physical address (ignored)
+	pub filesz: u64, // Size in file
+	pub memsz: u64,  // Size in memory
+	pub align: u64,  // Alignment
+}
+
+/// User program structure
+pub struct UserProgram {
+	pub name: String,
+	pub entry_point: u64,
+	pub code: Vec<u8>,
+	pub data: Vec<u8>,
+	pub bss_size: usize,
+}
+
+impl UserProgram {
+	/// Create a new user program
+	pub fn new(name: String, code: Vec<u8>) -> Self {
+		Self {
+			name,
+			entry_point: 0x400000, // Default entry point
+			code,
+			data: Vec::new(),
+			bss_size: 0,
+		}
+	}
+
+	/// Set entry point
+	pub fn set_entry_point(mut self, entry: u64) -> Self {
+		self.entry_point = entry;
+		self
+	}
+
+	/// Add data section
+	pub fn with_data(mut self, data: Vec<u8>) -> Self {
+		self.data = data;
+		self
+	}
+
+	/// Set BSS size
+	pub fn with_bss_size(mut self, size: usize) -> Self {
+		self.bss_size = size;
+		self
+	}
+}
+
+/// User mode manager
+pub struct UserModeManager {
+	programs: Vec<UserProgram>,
+}
+
+impl UserModeManager {
+	/// Create a new user mode manager
+	pub fn new() -> Self {
+		Self {
+			programs: Vec::new(),
+		}
+	}
+
+	/// Register a user program
+	pub fn register_program(&mut self, program: UserProgram) {
+		crate::info!("Registering user program: {}", program.name);
+		self.programs.push(program);
+	}
+
+	/// Load and execute a user program
+	pub fn exec_program(&self, name: &str, args: Vec<String>) -> Result<u32> {
+		// Find the program
+		let program = self
+			.programs
+			.iter()
+			.find(|p| p.name == name)
+			.ok_or(Error::NotFound)?;
+
+		crate::info!("Loading user program: {}", name);
+
+		// Create a new process
+		let pid = crate::process::allocate_pid();
+		let mut process = Process::new(pid, name.into(), Uid(0), Gid(0)); // Use dummy uid/gid
+
+		// Set up user mode address space
+		self.setup_user_address_space(&mut process, program)?;
+
+		// Create initial thread
+		let tid = crate::process::allocate_tid();
+		let mut thread = Thread::new(tid, pid, 0);
+
+		// Set up user mode context
+		let mut context = Context::new();
+		context.rip = program.entry_point;
+		context.rsp = 0x7FFFFFFFFFFF - 16; // Near top of user space
+		context.cs = USER_CS;
+		context.ss = USER_DS;
+		context.rflags = 0x202; // Enable interrupts
+
+		thread.context = context;
+		thread.state = ProcessState::Running;
+
+		// Add thread to process
+		process.add_thread(thread);
+
+		// Add process to process table
+		let mut table = crate::process::PROCESS_TABLE.lock();
+		table.add_process(process);
+
+		// Schedule the process
+		crate::scheduler::add_task(pid)?;
+
+		crate::info!("User program {} loaded and scheduled", name);
+		Ok(pid.0)
+	}
+
+	/// Set up user mode address space
+	fn setup_user_address_space(
+		&self,
+		process: &mut Process,
+		program: &UserProgram,
+	) -> Result<()> {
+		// Map code segment (executable)
+		let code_pages = (program.code.len() + 4095) / 4096;
+		for i in 0..code_pages {
+			let vaddr =
+				VirtAddr::new((program.entry_point + (i * 4096) as u64) as usize);
+			let paddr = crate::memory::allocate_page()?;
+
+			// Copy code data
+			let src_offset = i * 4096;
+			let src_len = core::cmp::min(4096, program.code.len() - src_offset);
+			if src_len > 0 {
+				unsafe {
+					let dst = paddr.as_u64() as *mut u8;
+					let src = program.code.as_ptr().add(src_offset);
+					core::ptr::copy_nonoverlapping(src, dst, src_len);
+				}
+			}
+
+			// Map with execute and read permissions
+			crate::memory::map_page(
+				vaddr,
+				paddr,
+				PageFlags::USER | PageFlags::PRESENT | PageFlags::EXECUTABLE,
+			)?;
+		}
+
+		// Map data segment (read/write)
+		if !program.data.is_empty() {
+			let data_start = 0x500000; // Data starts at 5MB
+			let data_pages = (program.data.len() + 4095) / 4096;
+
+			for i in 0..data_pages {
+				let vaddr =
+					VirtAddr::new((data_start + (i * 4096) as u64) as usize);
+				let paddr = crate::memory::allocate_page()?;
+
+				// Copy data
+				let src_offset = i * 4096;
+				let src_len = core::cmp::min(4096, program.data.len() - src_offset);
+				if src_len > 0 {
+					unsafe {
+						let dst = paddr.as_u64() as *mut u8;
+						let src = program.data.as_ptr().add(src_offset);
+						core::ptr::copy_nonoverlapping(src, dst, src_len);
+					}
+				}
+
+				// Map with read/write permissions
+				crate::memory::map_page(
+					vaddr,
+					paddr,
+					PageFlags::USER | PageFlags::PRESENT | PageFlags::WRITABLE,
+				)?;
+			}
+		}
+
+		// Map BSS segment (zero-initialized)
+		if program.bss_size > 0 {
+			let bss_start = 0x600000; // BSS starts at 6MB
+			let bss_pages = (program.bss_size + 4095) / 4096;
+
+			for i in 0..bss_pages {
+				let vaddr = VirtAddr::new((bss_start + (i * 4096) as u64) as usize);
+				let paddr = crate::memory::allocate_page()?;
+
+				// Zero-initialize
+				unsafe {
+					let dst = paddr.as_u64() as *mut u8;
+					core::ptr::write_bytes(dst, 0, 4096);
+				}
+
+				// Map with read/write permissions
+				crate::memory::map_page(
+					vaddr,
+					paddr,
+					PageFlags::USER | PageFlags::PRESENT | PageFlags::WRITABLE,
+				)?;
+			}
+		}
+
+		// Map user stack
+		let stack_pages = USER_STACK_SIZE / 4096;
+		let stack_start = 0x7FFFFFFFF000 - USER_STACK_SIZE as u64; // Near top of user space
+
+		for i in 0..stack_pages {
+			let vaddr = VirtAddr::new((stack_start + (i * 4096) as u64) as usize);
+			let paddr = crate::memory::allocate_page()?;
+
+			// Zero-initialize stack
+			unsafe {
+				let dst = paddr.as_u64() as *mut u8;
+				core::ptr::write_bytes(dst, 0, 4096);
+			}
+
+			// Map with read/write permissions
+			crate::memory::map_page(
+				vaddr,
+				paddr,
+				PageFlags::USER | PageFlags::PRESENT | PageFlags::WRITABLE,
+			)?;
+		}
+
+		crate::info!("User address space set up for process {}", process.pid);
+		Ok(())
+	}
+
+	/// List available programs
+	pub fn list_programs(&self) -> Vec<&str> {
+		self.programs.iter().map(|p| p.name.as_str()).collect()
+	}
+}
+
+/// Global user mode manager
+static mut USER_MODE_MANAGER: Option<UserModeManager> = None;
+static USER_MODE_INIT: core::sync::atomic::AtomicBool = core::sync::atomic::AtomicBool::new(false);
+
+/// Initialize user mode support
+pub fn init_usermode() -> Result<()> {
+	if USER_MODE_INIT.load(core::sync::atomic::Ordering::Acquire) {
+		return Ok(());
+	}
+
+	crate::info!("Initializing user mode support");
+
+	unsafe {
+		USER_MODE_MANAGER = Some(UserModeManager::new());
+	}
+
+	// Create some simple test programs
+	create_test_programs()?;
+
+	USER_MODE_INIT.store(true, core::sync::atomic::Ordering::Release);
+	crate::info!("User mode support initialized");
+	Ok(())
+}
+
+/// Get the global user mode manager
+pub fn get_user_mode_manager() -> Result<&'static mut UserModeManager> {
+	if !USER_MODE_INIT.load(core::sync::atomic::Ordering::Acquire) {
+		return Err(Error::WouldBlock);
+	}
+
+	unsafe { USER_MODE_MANAGER.as_mut().ok_or(Error::OutOfMemory) }
+}
+
+/// Create test user programs
+fn create_test_programs() -> Result<()> {
+	let manager = get_user_mode_manager()?;
+
+	// Simple "hello world" program
+	// This would normally be compiled user code, but for demo we'll use inline
+	// assembly
+	let hello_code = vec![
+		// mov rax, 1      ; sys_write
+		0x48, 0xc7, 0xc0, 0x01, 0x00, 0x00, 0x00, // mov rdi, 1      ; stdout
+		0x48, 0xc7, 0xc7, 0x01, 0x00, 0x00, 0x00,
+		// mov rsi, msg    ; message address (would be set at runtime)
+		0x48, 0xc7, 0xc6, 0x00, 0x50, 0x40, 0x00,
+		// mov rdx, 13     ; message length
+		0x48, 0xc7, 0xc2, 0x0d, 0x00, 0x00, 0x00, // syscall
+		0x0f, 0x05, // mov rax, 60     ; sys_exit
+		0x48, 0xc7, 0xc0, 0x3c, 0x00, 0x00, 0x00, // mov rdi, 0      ; exit code
+		0x48, 0xc7, 0xc7, 0x00, 0x00, 0x00, 0x00, // syscall
+		0x0f, 0x05,
+	];
+
+	let hello_data = b"Hello, World!\n".to_vec();
+
+	let hello_program = UserProgram::new("hello".into(), hello_code)
+		.set_entry_point(0x400000)
+		.with_data(hello_data);
+
+	manager.register_program(hello_program);
+
+	// Simple loop program (infinite loop for testing)
+	let loop_code = vec![
+		// loop:
+		// jmp loop
+		0xeb, 0xfe,
+	];
+
+	let loop_program = UserProgram::new("loop".into(), loop_code).set_entry_point(0x400000);
+
+	manager.register_program(loop_program);
+
+	crate::info!("Test user programs created");
+	Ok(())
+}
+
+/// Execute a user program
+pub fn exec_user_program(name: &str, args: Vec<String>) -> Result<u32> {
+	let manager = get_user_mode_manager()?;
+	manager.exec_program(name, args)
+}
+
+/// List available user programs
+pub fn list_user_programs() -> Result<Vec<&'static str>> {
+	let manager = get_user_mode_manager()?;
+	Ok(manager.list_programs())
+}

kernel/src/working_task.rs

@@ -0,0 +1,345 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Working kernel task implementation with actual functionality
+
+use alloc::{
+	boxed::Box,
+	format,
+	string::{String, ToString},
+	vec::Vec,
+};
+use core::sync::atomic::{AtomicU32, Ordering};
+
+use crate::arch::x86_64::context::Context;
+use crate::error::{Error, Result};
+use crate::memory::kmalloc;
+use crate::sync::Spinlock;
+use crate::types::{Pid, Tid};
+
+/// Task function type
+pub type TaskFunction = fn() -> ();
+
+/// Task state
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum TaskState {
+	Running,
+	Ready,
+	Blocked,
+	Terminated,
+}
+
+/// Working task structure
+#[derive(Debug, Clone)]
+pub struct Task {
+	pub tid: Tid,
+	pub pid: Pid,
+	pub name: String,
+	pub state: TaskState,
+	pub context: Context,
+	pub stack_base: usize,
+	pub stack_size: usize,
+	pub priority: u8,
+	pub cpu_time: u64,
+	pub creation_time: u64,
+}
+
+impl Task {
+	/// Create a new kernel task
+	pub fn new_kernel_task(
+		name: String,
+		function: TaskFunction,
+		stack_size: usize,
+	) -> Result<Self> {
+		// Use process subsystem to allocate TID to ensure uniqueness
+		let tid = crate::process::allocate_tid();
+
+		// Allocate stack
+		let stack_ptr = kmalloc::kmalloc(stack_size)?;
+		let stack_base = stack_ptr as usize;
+		let stack_top = stack_base + stack_size;
+
+		// Set up initial context
+		let mut context = Context::new();
+		context.rsp = (stack_top - 8) as u64; // Leave space for return address
+		context.rip = function as usize as u64;
+		context.rflags = 0x202; // Enable interrupts
+		context.cs = 0x08; // Kernel code segment
+		context.ds = 0x10; // Kernel data segment
+		context.es = 0x10;
+		context.fs = 0x10;
+		context.gs = 0x10;
+		context.ss = 0x10;
+
+		// Write a dummy return address to stack (for if function returns)
+		unsafe {
+			let return_addr_ptr = (stack_top - 8) as *mut u64;
+			*return_addr_ptr = task_exit_wrapper as usize as u64;
+		}
+
+		Ok(Task {
+			tid,
+			pid: Pid(0), // Kernel process
+			name,
+			state: TaskState::Ready,
+			context,
+			stack_base,
+			stack_size,
+			priority: 128, // Default priority
+			cpu_time: 0,
+			creation_time: crate::time::get_jiffies().0,
+		})
+	}
+
+	/// Set task priority
+	pub fn set_priority(&mut self, priority: u8) {
+		self.priority = priority;
+	}
+
+	/// Update CPU time
+	pub fn add_cpu_time(&mut self, time: u64) {
+		self.cpu_time += time;
+	}
+
+	/// Check if task should be scheduled
+	pub fn is_schedulable(&self) -> bool {
+		matches!(self.state, TaskState::Ready | TaskState::Running)
+	}
+
+	/// Terminate task
+	pub fn terminate(&mut self) {
+		self.state = TaskState::Terminated;
+
+		// Free stack memory
+		unsafe {
+			kmalloc::kfree(self.stack_base as *mut u8);
+		}
+	}
+}
+
+/// Wrapper function called when a task function returns
+extern "C" fn task_exit_wrapper() -> ! {
+	crate::info!("Kernel task exited normally");
+
+	// Mark current task as terminated
+	if let Some(current_tid) = crate::enhanced_scheduler::get_current_task() {
+		let _ = crate::enhanced_scheduler::remove_task(current_tid);
+	}
+
+	// Yield to scheduler
+	loop {
+		crate::enhanced_scheduler::schedule_next();
+		// If we get here, no other tasks to schedule
+		unsafe {
+			core::arch::asm!("hlt");
+		}
+	}
+}
+
+/// Working task manager
+pub struct TaskManager {
+	tasks: Spinlock<Vec<Task>>,
+	next_tid: AtomicU32,
+}
+
+impl TaskManager {
+	pub const fn new() -> Self {
+		Self {
+			tasks: Spinlock::new(Vec::new()),
+			next_tid: AtomicU32::new(1),
+		}
+	}
+
+	/// Spawn a new kernel task
+	pub fn spawn_kernel_task(
+		&self,
+		name: String,
+		function: TaskFunction,
+		stack_size: usize,
+	) -> Result<Tid> {
+		let task = Task::new_kernel_task(name.clone(), function, stack_size)?;
+		let tid = task.tid;
+
+		// Add to local task list
+		self.tasks.lock().push(task.clone());
+
+		// Add to PROCESS_TABLE so the low-level scheduler can find it
+		crate::process::add_kernel_thread(
+			tid,
+			task.context,
+			crate::memory::VirtAddr::new(task.context.rsp as usize),
+		)?;
+
+		// Add to enhanced scheduler
+		crate::enhanced_scheduler::add_task(
+			format!("task-{}", tid.0),
+			crate::enhanced_scheduler::Priority::Normal,
+		)?;
+
+		crate::info!(
+			"Spawned kernel task {} with TID {:?}",
+			format!("task-{}", tid.0),
+			tid
+		);
+
+		Ok(tid)
+	}
+
+	/// Get task by TID
+	pub fn get_task(&self, tid: Tid) -> Option<Task> {
+		self.tasks
+			.lock()
+			.iter()
+			.find(|task| task.tid == tid)
+			.cloned()
+	}
+
+	/// Update task state
+	pub fn set_task_state(&self, tid: Tid, state: TaskState) -> Result<()> {
+		let mut tasks = self.tasks.lock();
+		match tasks.iter_mut().find(|task| task.tid == tid) {
+			Some(task) => {
+				task.state = state;
+				Ok(())
+			}
+			None => Err(Error::NotFound),
+		}
+	}
+
+	/// Get all tasks
+	pub fn get_all_tasks(&self) -> Vec<Task> {
+		self.tasks.lock().clone()
+	}
+
+	/// Clean up terminated tasks
+	pub fn cleanup_terminated_tasks(&self) {
+		let mut tasks = self.tasks.lock();
+		tasks.retain(|task| task.state != TaskState::Terminated);
+	}
+
+	/// Get total number of tasks
+	pub fn get_task_count(&self) -> usize {
+		self.tasks.lock().len()
+	}
+}
+
+/// Global task manager
+static TASK_MANAGER: TaskManager = TaskManager::new();
+
+/// Initialize task management
+pub fn init_task_management() -> Result<()> {
+	crate::info!("Task management initialized");
+	Ok(())
+}
+
+/// Spawn a kernel task
+pub fn spawn_kernel_task(name: String, function: TaskFunction, stack_size: usize) -> Result<Tid> {
+	TASK_MANAGER.spawn_kernel_task(name, function, stack_size)
+}
+
+/// Create and spawn a kernel task (alias for compatibility)
+pub fn create_kernel_task(name: &str, function: TaskFunction) -> Result<Tid> {
+	spawn_kernel_task(name.to_string(), function, 8192) // 8KB default stack
+}
+
+/// Get task information
+pub fn get_task_info(tid: Tid) -> Option<Task> {
+	TASK_MANAGER.get_task(tid)
+}
+
+/// Set task state  
+pub fn set_task_state(tid: Tid, state: TaskState) -> Result<()> {
+	TASK_MANAGER.set_task_state(tid, state)
+}
+
+/// Get all tasks
+pub fn get_all_tasks() -> Vec<Task> {
+	TASK_MANAGER.get_all_tasks()
+}
+
+/// Clean up terminated tasks
+pub fn cleanup_tasks() {
+	TASK_MANAGER.cleanup_terminated_tasks();
+}
+
+/// Get total task count
+pub fn get_task_count() -> usize {
+	TASK_MANAGER.get_task_count()
+}
+
+/// Example kernel tasks for testing
+
+/// Idle task that runs when no other tasks are ready
+pub fn idle_task() {
+	loop {
+		unsafe {
+			core::arch::asm!("hlt"); // Halt until interrupt
+		}
+	}
+}
+
+/// Heartbeat task that prints periodic messages
+pub fn heartbeat_task() {
+	let mut counter = 0;
+	loop {
+		counter += 1;
+		crate::info!("Heartbeat: {}", counter);
+
+		// Sleep for a while (simplified - just loop)
+		for _ in 0..1_000_000 {
+			unsafe {
+				core::arch::asm!("pause");
+			}
+		}
+
+		if counter >= 10 {
+			crate::info!("Heartbeat task exiting after 10 beats");
+			break;
+		}
+	}
+}
+
+/// Memory monitor task
+pub fn memory_monitor_task() {
+	loop {
+		let stats = crate::memory::advanced_allocator::get_memory_stats();
+		crate::info!(
+			"Memory: allocated={} KB, peak={} KB, active_allocs={}",
+			stats.current_allocated / 1024,
+			stats.peak_usage / 1024,
+			stats.active_allocations
+		);
+
+		// Sleep for a while
+		for _ in 0..5_000_000 {
+			unsafe {
+				core::arch::asm!("pause");
+			}
+		}
+	}
+}
+
+/// Performance monitor task
+pub fn performance_monitor_task() {
+	loop {
+		let summary = crate::advanced_perf::get_performance_summary();
+		let mut total_counters = 0;
+		for (_, value) in &summary.counters {
+			total_counters += value;
+		}
+
+		if total_counters > 0 {
+			crate::info!(
+				"Performance: {} events, {} profilers active",
+				summary.total_events,
+				summary.profilers.len()
+			);
+		}
+
+		// Sleep for a while
+		for _ in 0..10_000_000 {
+			unsafe {
+				core::arch::asm!("pause");
+			}
+		}
+	}
+}