Kernel: VirtualRange doesn't store physical addresses of pages

This was unnecessarry allocation, since the page table allready
contains virtual address -> physical address mappings.

.gitmodules

@@ -0,0 +1,4 @@
+[submodule "kernel/lai"]
+	path = kernel/lai
+	url = https://github.com/managarm/lai.git
+	ignore = untracked

BAN/include/BAN/LinkedList.h

@@ -195,7 +195,7 @@ namespace BAN
 	template<typename T>
 	void LinkedList<T>::pop_back()
 	{
-		return remove(m_last);
+		remove(iterator(m_last, false));
 	}
 
 	template<typename T>

CMakeLists.txt

@@ -13,10 +13,16 @@ set(CMAKE_CXX_STANDARD_REQUIRED True)
 set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}/bin/${BANAN_ARCH}-banan_os-g++)
 set(CMAKE_CXX_COMPILER_WORKS True)
 
+set(CMAKE_C_COMPILER ${TOOLCHAIN_PREFIX}/bin/${BANAN_ARCH}-banan_os-gcc)
+set(CMAKE_C_COMPILER_WORKS True)
+
 if(NOT EXISTS ${CMAKE_CXX_COMPILER})
 	set(CMAKE_CXX_COMPILER g++)
 endif()
 
+add_compile_options(-mno-sse -mno-sse2)
+add_compile_definitions(__enable_sse=0)
+
 project(banan-os CXX)
 
 set(BANAN_BASE_SYSROOT ${CMAKE_SOURCE_DIR}/base-sysroot.tar.gz)
@@ -84,7 +90,13 @@ add_custom_target(check-fs
 )
 
 add_custom_target(qemu
-	COMMAND ${CMAKE_COMMAND} -E env BANAN_ARCH="${BANAN_ARCH}" DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/qemu.sh
+	COMMAND ${CMAKE_COMMAND} -E env BANAN_ARCH="${BANAN_ARCH}" DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/qemu.sh -accel kvm
+	DEPENDS image
+	USES_TERMINAL
+)
+
+add_custom_target(qemu-debug
+	COMMAND ${CMAKE_COMMAND} -E env BANAN_ARCH="${BANAN_ARCH}" DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/qemu.sh -d int -no-reboot
 	DEPENDS image
 	USES_TERMINAL
 )

kernel/CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.26)
 
-project(kernel CXX ASM)
+project(kernel CXX C ASM)
 
 if("${BANAN_ARCH}" STREQUAL "x86_64")
 	set(ELF_FORMAT elf64-x86-64)
@@ -32,7 +32,6 @@ set(KERNEL_SOURCES
 	kernel/Input/PS2Keymap.cpp
 	kernel/InterruptController.cpp
 	kernel/kernel.cpp
-	kernel/Memory/FixedWidthAllocator.cpp
 	kernel/Memory/GeneralAllocator.cpp
 	kernel/Memory/Heap.cpp
 	kernel/Memory/kmalloc.cpp
@@ -98,6 +97,14 @@ else()
 	message(FATAL_ERROR "unsupported architecure ${BANAN_ARCH}")
 endif()
 
+file(GLOB_RECURSE LAI_SOURCES
+	lai/*.c
+)
+set(LAI_SOURCES
+	${LAI_SOURCES}
+	kernel/lai_host.cpp
+)
+
 set(BAN_SOURCES
 	../BAN/BAN/New.cpp
 	../BAN/BAN/String.cpp
@@ -116,6 +123,7 @@ set(LIBELF_SOURCES
 
 set(KERNEL_SOURCES
 	${KERNEL_SOURCES}
+	${LAI_SOURCES}
 	${BAN_SOURCES}
 	${LIBC_SOURCES}
 	${LIBELF_SOURCES}
@@ -128,10 +136,9 @@ target_compile_definitions(kernel PUBLIC __is_kernel)
 target_compile_definitions(kernel PUBLIC __arch=${BANAN_ARCH})
 
 target_compile_options(kernel PUBLIC -O2 -g)
-target_compile_options(kernel PUBLIC -Wno-literal-suffix)
-target_compile_options(kernel PUBLIC -fno-rtti -fno-exceptions)
+target_compile_options(kernel PUBLIC $<$<COMPILE_LANGUAGE:CXX>:-Wno-literal-suffix -fno-rtti -fno-exceptions>)
 target_compile_options(kernel PUBLIC -fmacro-prefix-map=${CMAKE_CURRENT_SOURCE_DIR}=.)
-target_compile_options(kernel PUBLIC -fstack-protector -ffreestanding -Wall -Wextra -Werror=return-type -Wstack-usage=1024 -fno-omit-frame-pointer -mgeneral-regs-only)
+target_compile_options(kernel PUBLIC -fstack-protector -ffreestanding -Wall -Werror=return-type -Wstack-usage=1024 -fno-omit-frame-pointer -mgeneral-regs-only)
 
 if(ENABLE_KERNEL_UBSAN)
 	target_compile_options(kernel PUBLIC -fsanitize=undefined)
@@ -160,6 +167,7 @@ add_custom_command(
 
 add_custom_target(kernel-headers
 	COMMAND sudo rsync -a ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
+	COMMAND sudo rsync -a ${CMAKE_CURRENT_SOURCE_DIR}/lai/include/ ${BANAN_INCLUDE}/
 	DEPENDS sysroot
 	USES_TERMINAL
 )

kernel/arch/x86_64/IDT.cpp

@@ -139,10 +139,11 @@ namespace IDT
 
 	extern "C" void cpp_isr_handler(uint64_t isr, uint64_t error, Kernel::InterruptStack& interrupt_stack, const Registers* regs)
 	{
+#if __enable_sse
 		bool from_userspace = (interrupt_stack.cs & 0b11) == 0b11;
-
 		if (from_userspace)
 			Kernel::Thread::current().save_sse();
+#endif
 
 		pid_t tid = Kernel::Scheduler::current_tid();
 		pid_t pid = tid ? Kernel::Process::current().pid() : 0;
@@ -205,19 +206,22 @@ namespace IDT
 
 		ASSERT(Kernel::Thread::current().state() != Kernel::Thread::State::Terminated);
 
+#if __enable_sse
 		if (from_userspace)
 		{
 			ASSERT(Kernel::Thread::current().state() == Kernel::Thread::State::Executing);
 			Kernel::Thread::current().load_sse();
 		}
+#endif
 	}
 
 	extern "C" void cpp_irq_handler(uint64_t irq, Kernel::InterruptStack& interrupt_stack)
 	{
+#if __enable_sse
 		bool from_userspace = (interrupt_stack.cs & 0b11) == 0b11;
-
 		if (from_userspace)
 			Kernel::Thread::current().save_sse();
+#endif
 
 		if (Kernel::Scheduler::current_tid())
 		{
@@ -240,11 +244,13 @@ namespace IDT
 
 		ASSERT(Kernel::Thread::current().state() != Kernel::Thread::State::Terminated);
 
+#if __enable_sse
 		if (from_userspace)
 		{
 			ASSERT(Kernel::Thread::current().state() == Kernel::Thread::State::Executing);
 			Kernel::Thread::current().load_sse();
 		}
+#endif
 	}
 
 	static void flush_idt()

kernel/arch/x86_64/PageTable.cpp

@@ -110,6 +110,13 @@ namespace Kernel
 		return *s_current;
 	}
 
+	bool PageTable::is_valid_pointer(uintptr_t pointer)
+	{
+		if (!is_canonical(pointer))
+			return false;
+		return true;
+	}
+
 	static uint64_t* allocate_zeroed_page_aligned_page()
 	{
 		void* page = kmalloc(PAGE_SIZE, PAGE_SIZE, true);

kernel/include/kernel/ACPI.h

@@ -114,20 +114,31 @@ namespace Kernel
 		ACPI() = default;
 		BAN::ErrorOr<void> initialize_impl();
 
-		const SDTHeader* get_header_from_index(size_t);
-
 	private:
 		paddr_t m_header_table_paddr = 0;
 		vaddr_t m_header_table_vaddr = 0;
 		uint32_t m_entry_size = 0;
-		uint32_t m_entry_count = 0;
 
 		struct MappedPage
 		{
 			Kernel::paddr_t paddr;
 			Kernel::vaddr_t vaddr;
+
+			SDTHeader* as_header() { return (SDTHeader*)vaddr; }
 		};
 		BAN::Vector<MappedPage> m_mapped_headers;		
 	};
 
-}
+}
+
+namespace BAN::Formatter
+{
+	template<typename F>
+	void print_argument(F putc, const Kernel::ACPI::SDTHeader& header, const ValueFormat& format)
+	{ 
+		putc(header.signature[0]);
+		putc(header.signature[1]);
+		putc(header.signature[2]);
+		putc(header.signature[3]);
+	}
+}

kernel/include/kernel/Arch.h

@@ -21,4 +21,8 @@
 
 #include <stdint.h>
 
+#ifdef __cplusplus
 extern "C" uintptr_t read_rip();
+#else
+extern uintptr_t read_rip();
+#endif

kernel/include/kernel/Debug.h

@@ -29,6 +29,24 @@
 		Debug::DebugLock::unlock();							\
 	} while(false)
 
+#define dprintln_if(cond, ...)		\
+	do {							\
+		if constexpr(cond)			\
+			dprintln(__VA_ARGS__);	\
+	} while(false)
+
+#define dwarnln_if(cond, ...)		\
+	do {							\
+		if constexpr(cond)			\
+			dwarnln(__VA_ARGS__);	\
+	} while(false)
+
+#define derrorln_if(cond, ...)		\
+	do {							\
+		if constexpr(cond)			\
+			derrorln(__VA_ARGS__);	\
+	} while(false)
+
 #define BOCHS_BREAK() asm volatile("xchgw %bx, %bx")
 
 namespace Debug

kernel/include/kernel/Memory/FixedWidthAllocator.h

@@ -1,64 +0,0 @@
-#pragma once
-
-#include <BAN/Errors.h>
-#include <BAN/UniqPtr.h>
-#include <kernel/Memory/Heap.h>
-#include <kernel/Memory/PageTable.h>
-
-namespace Kernel
-{
-
-	class FixedWidthAllocator
-	{
-		BAN_NON_COPYABLE(FixedWidthAllocator);
-		BAN_NON_MOVABLE(FixedWidthAllocator);
-
-	public:
-		static BAN::ErrorOr<BAN::UniqPtr<FixedWidthAllocator>> create(PageTable&, uint32_t);
-		~FixedWidthAllocator();
-
-		BAN::ErrorOr<BAN::UniqPtr<FixedWidthAllocator>> clone(PageTable&);
-
-		vaddr_t allocate();
-		bool deallocate(vaddr_t);
-
-		uint32_t allocation_size() const { return m_allocation_size; }
-
-		uint32_t allocations() const { return m_allocations; }
-		uint32_t max_allocations() const;
-
-	private:
-		FixedWidthAllocator(PageTable&, uint32_t);
-		BAN::ErrorOr<void> initialize();
-
-		bool allocate_page_if_needed(vaddr_t, uint8_t flags);
-
-		struct node
-		{
-			node* prev { nullptr };
-			node* next { nullptr };
-			bool allocated { false };
-		};
-		vaddr_t address_of_node(const node*) const;
-		node* node_from_address(vaddr_t) const;
-		void allocate_page_for_node_if_needed(const node*);
-
-		void allocate_node(node*);
-		void deallocate_node(node*);
-
-	private:
-		static constexpr uint32_t m_min_allocation_size = 16;
-
-		PageTable& m_page_table;
-		const uint32_t m_allocation_size;
-		
-		vaddr_t m_nodes_page { 0 };
-		vaddr_t m_allocated_pages { 0 };
-
-		node* m_free_list { nullptr };
-		node* m_used_list { nullptr };
-
-		uint32_t m_allocations { 0 };
-	};
-
-}

kernel/include/kernel/Memory/PageTable.h

@@ -29,13 +29,15 @@ namespace Kernel
 		static PageTable& kernel();
 		static PageTable& current();
 
+		static bool is_valid_pointer(uintptr_t);
+
 		static BAN::ErrorOr<PageTable*> create_userspace();
 		~PageTable();
 
 		void unmap_page(vaddr_t);
 		void unmap_range(vaddr_t, size_t bytes);
 
-		void map_range_at(paddr_t, vaddr_t, size_t, flags_t);
+		void map_range_at(paddr_t, vaddr_t, size_t bytes, flags_t);
 		void map_page_at(paddr_t, vaddr_t, flags_t);
 
 		paddr_t physical_address_of(vaddr_t) const;

kernel/include/kernel/Memory/VirtualRange.h

@@ -40,7 +40,6 @@ namespace Kernel
 		vaddr_t					m_vaddr { 0 };
 		size_t					m_size { 0 };
 		PageTable::flags_t		m_flags { 0 };
-		BAN::Vector<paddr_t>	m_physical_pages;
 	};
 
 }

kernel/include/kernel/Networking/E1000.h

@@ -13,7 +13,7 @@ namespace Kernel
 	class E1000 final : public NetworkDriver
 	{
 	public:
-		static BAN::ErrorOr<BAN::UniqPtr<E1000>> create(const PCIDevice&);
+		static BAN::ErrorOr<BAN::UniqPtr<E1000>> create(PCI::Device&);
 		~E1000();
 
 		virtual uint8_t* get_mac_address() override { return m_mac_address; }
@@ -24,12 +24,12 @@ namespace Kernel
 
 	private:
 		E1000() = default;
-		BAN::ErrorOr<void> initialize(const PCIDevice&);
+		BAN::ErrorOr<void> initialize(PCI::Device&);
 
 		static void interrupt_handler();
 
-		void write32(uint16_t reg, uint32_t value);
 		uint32_t read32(uint16_t reg);
+		void write32(uint16_t reg, uint32_t value);
 
 		void detect_eeprom();
 		uint32_t eeprom_read(uint8_t addr);
@@ -44,8 +44,7 @@ namespace Kernel
 		void handle_receive();
 
 	private:
-		PCIDevice::BarType		m_bar_type {};
-		uint64_t				m_bar_addr {};
+		BAN::UniqPtr<PCI::BarRegion> m_bar_region;
 		bool					m_has_eerprom { false };
 		uint8_t					m_mac_address[6] {};
 		uint16_t				m_rx_current {};

kernel/include/kernel/PCI.h

@@ -1,28 +1,65 @@
 #pragma once
 
+#include <BAN/UniqPtr.h>
 #include <BAN/Vector.h>
+#include <kernel/Memory/Types.h>
 
-namespace Kernel
+namespace Kernel::PCI
 {
 
-	class PCIDevice
+	enum class BarType
 	{
-	public:
-		enum class BarType
-		{
-			INVAL,
-			MEM,
-			IO,
-		};
+		INVALID,
+		MEM,
+		IO,
+	};
+
+	class Device;
+
+	class BarRegion
+	{
+		BAN_NON_COPYABLE(BarRegion);
 
 	public:
-		PCIDevice(uint8_t, uint8_t, uint8_t);
+		static BAN::ErrorOr<BAN::UniqPtr<BarRegion>> create(PCI::Device&, uint8_t bar_num);
+		~BarRegion();
+
+		BarType type() const { return m_type; }
+		vaddr_t vaddr() const { return m_vaddr; }
+		paddr_t paddr() const { return m_paddr; }
+		size_t size() const { return m_size; }
+
+		void write8(off_t, uint8_t);
+		void write16(off_t, uint16_t);
+		void write32(off_t, uint32_t);
+
+		uint8_t read8(off_t);
+		uint16_t read16(off_t);
+		uint32_t read32(off_t);
+
+	private:
+		BarRegion(BarType, paddr_t, size_t);
+		BAN::ErrorOr<void> initialize();
+
+	private:
+		const BarType	m_type	{};
+		const paddr_t	m_paddr	{};
+		const size_t	m_size	{};
+		vaddr_t			m_vaddr	{};
+	};
+
+	class Device
+	{
+	public:
+		Device(uint8_t, uint8_t, uint8_t);
 
 		uint32_t read_dword(uint8_t) const;
 		uint16_t read_word(uint8_t) const;
 		uint8_t  read_byte(uint8_t) const;
 
-		void write_dword(uint8_t, uint32_t) const;
+		void write_dword(uint8_t, uint32_t);
+		void write_word(uint8_t, uint16_t);
+		void write_byte(uint8_t, uint8_t);
 
 		uint8_t bus() const { return m_bus; }
 		uint8_t dev() const { return m_dev; }
@@ -32,17 +69,24 @@ namespace Kernel
 		uint8_t subclass() const { return m_subclass; }
 		uint8_t prog_if() const { return m_prog_if; }
 
-		BarType read_bar_type(uint8_t) const;
-		uint64_t read_bar_address(uint8_t) const;
+		uint8_t header_type() const { return m_header_type; }
 
-		void enable_bus_mastering() const;
-		void disable_bus_mastering() const;
+		BAN::ErrorOr<BAN::UniqPtr<BarRegion>> allocate_bar_region(uint8_t bar_num);
 
-		void enable_memory_space() const;
-		void disable_memory_space() const;
+		void enable_bus_mastering();
+		void disable_bus_mastering();
 
-		void enable_pin_interrupts() const;
-		void disable_pin_interrupts() const;
+		void enable_memory_space();
+		void disable_memory_space();
+
+		void enable_io_space();
+		void disable_io_space();
+
+		void enable_pin_interrupts();
+		void disable_pin_interrupts();
+
+	private:
+		void enumerate_capabilites();
 
 	private:
 		uint8_t m_bus;
@@ -56,19 +100,27 @@ namespace Kernel
 		uint8_t m_header_type;
 	};
 
-	class PCI
+	class PCIManager
 	{
-		BAN_NON_COPYABLE(PCI);
-		BAN_NON_MOVABLE(PCI);
+		BAN_NON_COPYABLE(PCIManager);
+		BAN_NON_MOVABLE(PCIManager);
 
 	public:
 		static void initialize();
-		static PCI& get();
+		static PCIManager& get();
 		
-		const BAN::Vector<PCIDevice>& devices() const { return m_devices; }
+		const BAN::Vector<PCI::Device>& devices() const { return m_devices; }
+
+		static uint32_t read_config_dword(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset);
+		static uint16_t read_config_word(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset);
+		static uint8_t read_config_byte(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset);
+
+		static void write_config_dword(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset, uint32_t value);
+		static void write_config_word(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset, uint16_t value);
+		static void write_config_byte(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset, uint8_t value);
 
 	private:
-		PCI() = default;
+		PCIManager() = default;
 		void check_function(uint8_t bus, uint8_t dev, uint8_t func);
 		void check_device(uint8_t bus, uint8_t dev);
 		void check_bus(uint8_t bus);
@@ -76,7 +128,7 @@ namespace Kernel
 		void initialize_devices();
 
 	private:
-		BAN::Vector<PCIDevice> m_devices;
+		BAN::Vector<PCI::Device> m_devices;
 	};
 
 }

kernel/include/kernel/Process.h

@@ -6,8 +6,6 @@
 #include <BAN/Vector.h>
 #include <kernel/Credentials.h>
 #include <kernel/FS/Inode.h>
-#include <kernel/Memory/FixedWidthAllocator.h>
-#include <kernel/Memory/GeneralAllocator.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/VirtualRange.h>
 #include <kernel/OpenFileDescriptorSet.h>
@@ -15,6 +13,7 @@
 #include <kernel/Terminal/TTY.h>
 #include <kernel/Thread.h>
 
+#include <sys/mman.h>
 #include <termios.h>
 
 namespace LibELF { class ELF; }
@@ -70,8 +69,6 @@ namespace Kernel
 		BAN::ErrorOr<long> sys_sleep(int seconds);
 		BAN::ErrorOr<long> sys_nanosleep(const timespec* rqtp, timespec* rmtp);
 
-		BAN::ErrorOr<long> sys_setenvp(char** envp);
-
 		BAN::ErrorOr<long> sys_setpwd(const char* path);
 		BAN::ErrorOr<long> sys_getpwd(char* buffer, size_t size);
 
@@ -115,8 +112,8 @@ namespace Kernel
 
 		BAN::ErrorOr<long> sys_read_dir_entries(int fd, DirectoryEntryList* buffer, size_t buffer_size);
 
-		BAN::ErrorOr<long> sys_alloc(size_t);
-		BAN::ErrorOr<long> sys_free(void*);
+		BAN::ErrorOr<long> sys_mmap(const sys_mmap_t&);
+		BAN::ErrorOr<long> sys_munmap(void* addr, size_t len);
 
 		BAN::ErrorOr<long> sys_signal(int, void (*)(int));
 		BAN::ErrorOr<long> sys_raise(int signal);
@@ -143,7 +140,7 @@ namespace Kernel
 		static void register_process(Process*);
 
 		// Load an elf file to virtual address space of the current page table
-		static BAN::ErrorOr<BAN::UniqPtr<LibELF::ELF>> load_elf_for_exec(const Credentials&, BAN::StringView file_path, const BAN::String& cwd, const BAN::Vector<BAN::StringView>& path_env);
+		static BAN::ErrorOr<BAN::UniqPtr<LibELF::ELF>> load_elf_for_exec(const Credentials&, BAN::StringView file_path, const BAN::String& cwd);
 		
 		// Copy an elf file from the current page table to the processes own
 		void load_elf_to_memory(LibELF::ELF&);
@@ -161,11 +158,17 @@ namespace Kernel
 			int waiting { 0 };
 		};
 
+		struct MappedRange
+		{
+			bool can_be_unmapped;
+			BAN::UniqPtr<VirtualRange> range;
+		};
+
 		Credentials m_credentials;
 
 		OpenFileDescriptorSet m_open_file_descriptors;
 
-		BAN::Vector<BAN::UniqPtr<VirtualRange>> m_mapped_ranges;
+		BAN::Vector<MappedRange> m_mapped_ranges;
 
 		pid_t m_sid;
 		pid_t m_pgrp;
@@ -177,9 +180,6 @@ namespace Kernel
 		BAN::String m_working_directory;
 		BAN::Vector<Thread*> m_threads;
 
-		BAN::Vector<BAN::UniqPtr<FixedWidthAllocator>> m_fixed_width_allocators;
-		BAN::UniqPtr<GeneralAllocator> m_general_allocator;
-
 		vaddr_t m_signal_handlers[_SIGMAX + 1] { };
 		uint64_t m_signal_pending_mask { 0 };
 

kernel/include/kernel/Storage/ATAController.h

@@ -11,13 +11,13 @@ namespace Kernel
 	class ATAController final : public StorageController
 	{
 	public:
-		static BAN::ErrorOr<BAN::RefPtr<ATAController>> create(const PCIDevice&);
+		static BAN::ErrorOr<BAN::RefPtr<ATAController>> create(const PCI::Device&);
 
 		virtual BAN::Vector<BAN::RefPtr<StorageDevice>> devices() override;
 
 	private:
 		ATAController();
-		BAN::ErrorOr<void> initialize(const PCIDevice& device);
+		BAN::ErrorOr<void> initialize(const PCI::Device& device);
 
 	private:
 		ATABus* m_buses[2] { nullptr, nullptr };

kernel/include/kernel/Thread.h

@@ -82,8 +82,10 @@ namespace Kernel
 
 		bool is_userspace() const { return m_is_userspace; }
 
+#if __enable_sse
 		void save_sse() { asm volatile("fxsave %0" :: "m"(m_sse_storage)); }
 		void load_sse() { asm volatile("fxrstor %0" :: "m"(m_sse_storage)); }
+#endif
 
 	private:
 		Thread(pid_t tid, Process*);
@@ -114,7 +116,9 @@ namespace Kernel
 
 		uint64_t m_terminate_blockers { 0 };
 
+#if __enable_sse
 		alignas(16) uint8_t m_sse_storage[512] {};
+#endif
 
 		friend class Scheduler;
 	};

kernel/include/kernel/Timer/Timer.h

@@ -4,6 +4,8 @@
 #include <BAN/Vector.h>
 #include <kernel/Timer/RTC.h>
 
+#include <time.h>
+
 namespace Kernel
 {
 

kernel/kernel/ACPI.cpp

@@ -3,6 +3,8 @@
 #include <kernel/ACPI.h>
 #include <kernel/Memory/PageTable.h>
 
+#include <lai/core.h>
+
 #define RSPD_SIZE	20
 #define RSPDv2_SIZE	36
 
@@ -43,6 +45,7 @@ namespace Kernel
 		if (s_instance == nullptr)
 			return BAN::Error::from_errno(ENOMEM);
 		TRY(s_instance->initialize_impl());
+		lai_create_namespace();
 		return {};
 	}
 
@@ -101,6 +104,9 @@ namespace Kernel
 		const RSDP* rsdp = locate_rsdp();
 		if (rsdp == nullptr)
 			return BAN::Error::from_error_code(ErrorCode::ACPI_NoRootSDT);
+		lai_set_acpi_revision(rsdp->revision);
+
+		uint32_t root_entry_count = 0;
 
 		if (rsdp->revision >= 2)
 		{
@@ -115,7 +121,7 @@ namespace Kernel
 
 			m_header_table_paddr = (paddr_t)xsdt->entries + (rsdp->rsdt_address & PAGE_ADDR_MASK);
 			m_entry_size = 8;
-			m_entry_count = (xsdt->length - sizeof(SDTHeader)) / 8;
+			root_entry_count = (xsdt->length - sizeof(SDTHeader)) / 8;
 		}
 		else
 		{
@@ -130,10 +136,10 @@ namespace Kernel
 
 			m_header_table_paddr = (paddr_t)rsdt->entries + (rsdp->rsdt_address & PAGE_ADDR_MASK);
 			m_entry_size = 4;
-			m_entry_count = (rsdt->length - sizeof(SDTHeader)) / 4;
+			root_entry_count = (rsdt->length - sizeof(SDTHeader)) / 4;
 		}
 
-		size_t needed_pages = range_page_count(m_header_table_paddr, m_entry_count * m_entry_size);
+		size_t needed_pages = range_page_count(m_header_table_paddr, root_entry_count * m_entry_size);
 		m_header_table_vaddr = PageTable::kernel().reserve_free_contiguous_pages(needed_pages, KERNEL_OFFSET);
 		ASSERT(m_header_table_vaddr);
 
@@ -146,61 +152,85 @@ namespace Kernel
 			PageTable::Flags::Present
 		);
 
-		for (uint32_t i = 0; i < m_entry_count; i++)
+		auto map_header =
+			[](paddr_t header_paddr) -> vaddr_t
+			{
+				PageTable::kernel().map_page_at(header_paddr & PAGE_ADDR_MASK, 0, PageTable::Flags::Present);
+				size_t header_length = ((SDTHeader*)(header_paddr % PAGE_SIZE))->length;
+				PageTable::kernel().unmap_page(0);
+
+				size_t needed_pages = range_page_count(header_paddr, header_length);
+				vaddr_t page_vaddr = PageTable::kernel().reserve_free_contiguous_pages(needed_pages, KERNEL_OFFSET);
+				ASSERT(page_vaddr);
+				
+				PageTable::kernel().map_range_at(
+					header_paddr & PAGE_ADDR_MASK,
+					page_vaddr,
+					needed_pages * PAGE_SIZE,
+					PageTable::Flags::Present
+				);
+
+				auto* header = (SDTHeader*)(page_vaddr + (header_paddr % PAGE_SIZE));
+				if (!is_valid_std_header(header))
+				{
+					PageTable::kernel().unmap_range(page_vaddr, needed_pages * PAGE_SIZE);
+					return 0;
+				}
+
+				return page_vaddr + (header_paddr % PAGE_SIZE);
+			};
+
+		for (uint32_t i = 0; i < root_entry_count; i++)
 		{
 			paddr_t header_paddr = (m_entry_size == 4) ?
 				((uint32_t*)m_header_table_vaddr)[i] :
 				((uint64_t*)m_header_table_vaddr)[i];
 			
-			PageTable::kernel().map_page_at(header_paddr & PAGE_ADDR_MASK, 0, PageTable::Flags::Present);
-			size_t header_length = ((SDTHeader*)(header_paddr % PAGE_SIZE))->length;
-			PageTable::kernel().unmap_page(0);
-
-			size_t needed_pages = range_page_count(header_paddr, header_length);
-			vaddr_t page_vaddr = PageTable::kernel().reserve_free_contiguous_pages(needed_pages, KERNEL_OFFSET);
-			ASSERT(page_vaddr);
-			
-			PageTable::kernel().map_range_at(
-				header_paddr & PAGE_ADDR_MASK,
-				page_vaddr,
-				needed_pages * PAGE_SIZE,
-				PageTable::Flags::Present
-			);
+			vaddr_t header_vaddr = map_header(header_paddr);
+			if (header_vaddr == 0)
+				continue;
 
 			MUST(m_mapped_headers.push_back({
 				.paddr = header_paddr,
-				.vaddr = page_vaddr + (header_paddr % PAGE_SIZE)
+				.vaddr = header_vaddr
 			}));
 		}
 
+		for (size_t i = 0; i < m_mapped_headers.size(); i++)
+		{
+			auto* header = m_mapped_headers[i].as_header();
+			dprintln("found header {}", *header);
+
+			if (memcmp(header->signature, "FACP", 4) == 0)
+			{
+				auto* fadt = (FADT*)header;
+				paddr_t dsdt_paddr = fadt->x_dsdt;
+				if (dsdt_paddr == 0 || !PageTable::is_valid_pointer(dsdt_paddr))
+					dsdt_paddr = fadt->dsdt;
+
+				vaddr_t dsdt_vaddr = map_header(dsdt_paddr);
+				if (dsdt_vaddr == 0)
+					continue;
+
+				MUST(m_mapped_headers.push_back({
+					.paddr = dsdt_paddr,
+					.vaddr = dsdt_vaddr
+				}));
+			}
+		}
+
 		return {};
 	}
 
 	const ACPI::SDTHeader* ACPI::get_header(const char signature[4])
 	{
-		for (uint32_t i = 0; i < m_entry_count; i++)
+		for (auto& mapped_header : m_mapped_headers)
 		{
-			const SDTHeader* header = get_header_from_index(i);
-			if (is_valid_std_header(header) && memcmp(header->signature, signature, 4) == 0)
+			auto* header = mapped_header.as_header();
+			if (memcmp(header->signature, signature, 4) == 0)
 				return header;
 		}
 		return nullptr;
 	}
 
-	const ACPI::SDTHeader* ACPI::get_header_from_index(size_t index)
-	{
-		ASSERT(index < m_entry_count);
-		ASSERT(m_entry_size == 4 || m_entry_size == 8);
-
-		paddr_t header_paddr = (m_entry_size == 4) ?
-			((uint32_t*)m_header_table_vaddr)[index] :
-			((uint64_t*)m_header_table_vaddr)[index];
-
-		for (const auto& page : m_mapped_headers)
-			if (page.paddr == header_paddr)
-				return (SDTHeader*)page.vaddr;
-
-		ASSERT_NOT_REACHED();
-	}
-
 }

kernel/kernel/Memory/FixedWidthAllocator.cpp

@@ -1,288 +0,0 @@
-#include <kernel/Memory/FixedWidthAllocator.h>
-
-namespace Kernel
-{
-
-	BAN::ErrorOr<BAN::UniqPtr<FixedWidthAllocator>> FixedWidthAllocator::create(PageTable& page_table, uint32_t allocation_size)
-	{
-		auto* allocator_ptr = new FixedWidthAllocator(page_table, allocation_size);
-		if (allocator_ptr == nullptr)
-			return BAN::Error::from_errno(ENOMEM);
-		auto allocator = BAN::UniqPtr<FixedWidthAllocator>::adopt(allocator_ptr);
-		TRY(allocator->initialize());
-		return allocator;
-	}
-
-	FixedWidthAllocator::FixedWidthAllocator(PageTable& page_table, uint32_t allocation_size)
-		: m_page_table(page_table)
-		, m_allocation_size(BAN::Math::max(allocation_size, m_min_allocation_size))
-	{
-		ASSERT(BAN::Math::is_power_of_two(allocation_size));
-	}
-
-	BAN::ErrorOr<void> FixedWidthAllocator::initialize()
-	{
-		m_nodes_page = (vaddr_t)kmalloc(PAGE_SIZE);
-		if (!m_nodes_page)
-			return BAN::Error::from_errno(ENOMEM);
-
-		m_allocated_pages = (vaddr_t)kmalloc(PAGE_SIZE);
-		if (!m_allocated_pages)
-		{
-			kfree((void*)m_nodes_page);
-			m_nodes_page = 0;
-			return BAN::Error::from_errno(ENOMEM);
-		}
-
-		memset((void*)m_nodes_page, 0, PAGE_SIZE);
-		memset((void*)m_allocated_pages, 0, PAGE_SIZE);
-
-		node* node_table = (node*)m_nodes_page;
-		for (uint32_t i = 0; i < PAGE_SIZE / sizeof(node); i++)
-		{
-			node_table[i].next = &node_table[i + 1];
-			node_table[i].prev = &node_table[i - 1];
-		}
-		node_table[0].prev = nullptr;
-		node_table[PAGE_SIZE / sizeof(node) - 1].next = nullptr;
-
-		m_free_list = node_table;
-		m_used_list = nullptr;
-
-		return {};
-	}
-
-	FixedWidthAllocator::~FixedWidthAllocator()
-	{
-		if (m_nodes_page && m_allocated_pages)
-		{
-			for (uint32_t page_index = 0; page_index < PAGE_SIZE / sizeof(vaddr_t); page_index++)
-			{
-				vaddr_t page_vaddr = ((vaddr_t*)m_allocated_pages)[page_index];
-				if (page_vaddr == 0)
-					continue;
-
-				ASSERT(!m_page_table.is_page_free(page_vaddr));
-				Heap::get().release_page(m_page_table.physical_address_of(page_vaddr));
-				m_page_table.unmap_page(page_vaddr);
-			}
-		}
-
-		if (m_nodes_page)
-			kfree((void*)m_nodes_page);
-		if (m_allocated_pages)
-			kfree((void*)m_allocated_pages);
-	}
-
-	paddr_t FixedWidthAllocator::allocate()
-	{
-		if (m_free_list == nullptr)
-			return 0;
-		node* node = m_free_list;
-		allocate_node(node);
-		allocate_page_for_node_if_needed(node);
-		return address_of_node(node);
-	}
-
-	bool FixedWidthAllocator::deallocate(vaddr_t address)
-	{
-		if (address % m_allocation_size)
-			return false;
-		if (m_allocations == 0)
-			return false;
-		
-		node* node = node_from_address(address);
-		if (node == nullptr)
-			return false;
-
-		if (!node->allocated)
-		{
-			dwarnln("deallocate called on unallocated address");
-			return true;
-		}
-
-		deallocate_node(node);
-		return true;
-	}
-
-	void FixedWidthAllocator::allocate_node(node* node)
-	{
-		ASSERT(!node->allocated);
-		node->allocated = true;
-
-		if (node == m_free_list)
-			m_free_list = node->next;
-
-		if (node->prev)
-			node->prev->next = node->next;
-		if (node->next)
-			node->next->prev = node->prev;
-
-		node->next = m_used_list;
-		node->prev = nullptr;
-
-		if (m_used_list)
-			m_used_list->prev = node;
-		m_used_list = node;
-
-		m_allocations++;
-	}
-
-	void FixedWidthAllocator::deallocate_node(node* node)
-	{
-		ASSERT(node->allocated);
-		node->allocated = false;
-
-		if (node == m_used_list)
-			m_used_list = node->next;
-
-		if (node->prev)
-			node->prev->next = node->next;
-		if (node->next)
-			node->next->prev = node->prev;
-
-		node->next = m_free_list;
-		node->prev = nullptr;
-
-		if (m_free_list)
-			m_free_list->prev = node;
-		m_free_list = node;
-
-		m_allocations--;
-	}
-
-	uint32_t FixedWidthAllocator::max_allocations() const
-	{
-		return PAGE_SIZE / sizeof(node);
-	}
-
-	vaddr_t FixedWidthAllocator::address_of_node(const node* node) const
-	{
-		uint32_t index = node - (struct node*)m_nodes_page;
-
-		uint32_t page_index = index / (PAGE_SIZE / m_allocation_size);
-		ASSERT(page_index < PAGE_SIZE / sizeof(vaddr_t));
-
-		uint32_t offset = index % (PAGE_SIZE / m_allocation_size);
-
-		vaddr_t page_begin = ((vaddr_t*)m_allocated_pages)[page_index];
-		ASSERT(page_begin);
-
-		return page_begin + offset * m_allocation_size;
-	}
-
-	FixedWidthAllocator::node* FixedWidthAllocator::node_from_address(vaddr_t address) const
-	{
-		// TODO: This probably should be optimized from O(n) preferably to O(1) but I
-		//       don't want to think about performance now.
-		
-		ASSERT(address % m_allocation_size == 0);
-
-		vaddr_t page_begin = address / PAGE_SIZE * PAGE_SIZE;
-
-		for (uint32_t page_index = 0; page_index < PAGE_SIZE / sizeof(vaddr_t); page_index++)
-		{
-			vaddr_t vaddr = ((vaddr_t*)m_allocated_pages)[page_index];
-			if (vaddr != page_begin)
-				continue;
-			
-			uint32_t offset = (address - page_begin) / m_allocation_size;
-
-			node* result = (node*)m_nodes_page;
-			result += page_index * PAGE_SIZE / m_allocation_size;
-			result += offset;
-			ASSERT(address_of_node(result) == address);
-			return result;
-		}
-
-		return nullptr;
-	}
-
-	void FixedWidthAllocator::allocate_page_for_node_if_needed(const node* node)
-	{
-		uint32_t index = node - (struct node*)m_nodes_page;
-
-		uint32_t page_index = index / (PAGE_SIZE / m_allocation_size);
-		ASSERT(page_index < PAGE_SIZE / sizeof(vaddr_t));
-
-		vaddr_t& page_vaddr = ((vaddr_t*)m_allocated_pages)[page_index];
-		if (page_vaddr)
-			return;
-		
-		paddr_t page_paddr = Heap::get().take_free_page();
-		ASSERT(page_paddr);
-
-		page_vaddr = m_page_table.reserve_free_page(0x300000);
-		ASSERT(page_vaddr);
-		
-		m_page_table.map_page_at(page_paddr, page_vaddr, PageTable::Flags::UserSupervisor | PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-	}
-
-	bool FixedWidthAllocator::allocate_page_if_needed(vaddr_t vaddr, uint8_t flags)
-	{
-		ASSERT(vaddr % PAGE_SIZE == 0);
-
-		// Check if page is already allocated
-		for (uint32_t page_index = 0; page_index < PAGE_SIZE / sizeof(vaddr_t); page_index++)
-		{
-			vaddr_t page_begin = ((vaddr_t*)m_allocated_pages)[page_index];
-			if (vaddr == page_begin)
-				return false;
-		}
-
-		// Page is not allocated so the vaddr must not be in use
-		ASSERT(m_page_table.is_page_free(vaddr));
-
-		// Allocate the vaddr on empty page
-		for (uint32_t page_index = 0; page_index < PAGE_SIZE / sizeof(vaddr_t); page_index++)
-		{
-			vaddr_t& page_begin = ((vaddr_t*)m_allocated_pages)[page_index];
-			if (page_begin == 0)
-			{
-				paddr_t paddr = Heap::get().take_free_page();
-				ASSERT(paddr);
-				m_page_table.map_page_at(paddr, vaddr, flags);
-				page_begin = vaddr;
-				return true;
-			}
-		}
-
-		ASSERT_NOT_REACHED();
-	}
-
-	BAN::ErrorOr<BAN::UniqPtr<FixedWidthAllocator>> FixedWidthAllocator::clone(PageTable& new_page_table)
-	{
-		auto allocator = TRY(FixedWidthAllocator::create(new_page_table, allocation_size()));
-
-		m_page_table.lock();
-		ASSERT(m_page_table.is_page_free(0));
-
-		for (node* node = m_used_list; node; node = node->next)
-		{
-			ASSERT(node->allocated);
-
-			vaddr_t vaddr = address_of_node(node);
-			vaddr_t page_begin = vaddr & PAGE_ADDR_MASK;
-			PageTable::flags_t flags = m_page_table.get_page_flags(page_begin);
-
-			// Allocate and copy all data from this allocation to the new one
-			if (allocator->allocate_page_if_needed(page_begin, flags))
-			{
-				paddr_t paddr = new_page_table.physical_address_of(page_begin);
-				m_page_table.map_page_at(paddr, 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-				memcpy((void*)0, (void*)page_begin, PAGE_SIZE);
-			}
-
-			// Now that we are sure the page is allocated, we can access the node
-			struct node* new_node = allocator->node_from_address(vaddr);
-			allocator->allocate_node(new_node);
-		}
-
-		m_page_table.unmap_page(0);
-
-		m_page_table.unlock();
-
-		return allocator;
-	}
-
-}

kernel/kernel/Memory/VirtualRange.cpp

@@ -1,4 +1,3 @@
-#include <BAN/ScopeGuard.h>
 #include <kernel/LockGuard.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/VirtualRange.h>
@@ -21,27 +20,25 @@ namespace Kernel
 		result->m_vaddr = vaddr;
 		result->m_size = size;
 		result->m_flags = flags;
-		TRY(result->m_physical_pages.reserve(size / PAGE_SIZE));
 
 		ASSERT(page_table.reserve_range(vaddr, size));
-		BAN::ScopeGuard unmapper([vaddr, size, &page_table] { page_table.unmap_range(vaddr, size); });
 
-		TRY(result->m_physical_pages.reserve(size / PAGE_SIZE));
-		for (size_t offset = 0; offset < size; offset += PAGE_SIZE)
+		size_t needed_pages = size / PAGE_SIZE;
+
+		for (size_t i = 0; i < needed_pages; i++)
 		{
 			paddr_t paddr = Heap::get().take_free_page();
 			if (paddr == 0)
 			{
-				for (paddr_t release : result->m_physical_pages)
-					Heap::get().release_page(release);
+				for (size_t j = 0; j < i; j++)
+					Heap::get().release_page(page_table.physical_address_of(vaddr + j * PAGE_SIZE));
+				page_table.unmap_range(vaddr, size);
+				result->m_vaddr = 0;
 				return BAN::Error::from_errno(ENOMEM);
 			}
-			MUST(result->m_physical_pages.push_back(paddr));
-			page_table.map_page_at(paddr, vaddr + offset, flags);
+			page_table.map_page_at(paddr, vaddr + i * PAGE_SIZE, flags);
 		}
 
-		unmapper.disable();
-
 		return result;
 	}
 
@@ -49,6 +46,7 @@ namespace Kernel
 	{
 		ASSERT(size % PAGE_SIZE == 0);
 		ASSERT(vaddr_start > 0);
+		ASSERT(vaddr_start + size <= vaddr_end);
 
 		// Align vaddr range to page boundaries
 		if (size_t rem = vaddr_start % PAGE_SIZE)
@@ -64,37 +62,32 @@ namespace Kernel
 		auto result = BAN::UniqPtr<VirtualRange>::adopt(result_ptr);
 
 		result->m_kmalloc = false;
+		result->m_vaddr = 0;
 		result->m_size = size;
 		result->m_flags = flags;
-		TRY(result->m_physical_pages.reserve(size / PAGE_SIZE));
 
 		vaddr_t vaddr = page_table.reserve_free_contiguous_pages(size / PAGE_SIZE, vaddr_start, vaddr_end);
 		if (vaddr == 0)
 			return BAN::Error::from_errno(ENOMEM);
+		ASSERT(vaddr + size <= vaddr_end);
 		result->m_vaddr = vaddr;
 
-		BAN::ScopeGuard unmapper([vaddr, size, &page_table] { page_table.unmap_range(vaddr, size); });
-		if (vaddr + size > vaddr_end)
-			return BAN::Error::from_errno(ENOMEM);
+		size_t needed_pages = size / PAGE_SIZE;
 
-		result->m_vaddr = vaddr;
-
-		TRY(result->m_physical_pages.reserve(size / PAGE_SIZE));
-		for (size_t offset = 0; offset < size; offset += PAGE_SIZE)
+		for (size_t i = 0; i < needed_pages; i++)
 		{
 			paddr_t paddr = Heap::get().take_free_page();
 			if (paddr == 0)
 			{
-				for (paddr_t release : result->m_physical_pages)
-					Heap::get().release_page(release);
+				for (size_t j = 0; j < i; j++)
+					Heap::get().release_page(page_table.physical_address_of(vaddr + j * PAGE_SIZE));
+				page_table.unmap_range(vaddr, size);
+				result->m_vaddr = 0;
 				return BAN::Error::from_errno(ENOMEM);
 			}
-			MUST(result->m_physical_pages.push_back(paddr));
-			page_table.map_page_at(paddr, vaddr + offset, flags);
+			page_table.map_page_at(paddr, vaddr + i * PAGE_SIZE, flags);
 		}
 
-		unmapper.disable();
-
 		return result;
 	}
 
@@ -122,33 +115,34 @@ namespace Kernel
 
 	VirtualRange::~VirtualRange()
 	{
-		if (m_kmalloc)
-		{
-			kfree((void*)m_vaddr);
+		if (m_vaddr == 0)
 			return;
-		}
 
-		m_page_table.unmap_range(vaddr(), size());
-		for (paddr_t page : m_physical_pages)
-			Heap::get().release_page(page);
+		if (m_kmalloc)
+			kfree((void*)m_vaddr);
+		else
+		{
+			for (size_t offset = 0; offset < size(); offset += PAGE_SIZE)
+				Heap::get().release_page(m_page_table.physical_address_of(vaddr() + offset));
+			m_page_table.unmap_range(vaddr(), size());
+		}
 	}
 
 	BAN::ErrorOr<BAN::UniqPtr<VirtualRange>> VirtualRange::clone(PageTable& page_table)
 	{
+		ASSERT(&PageTable::current() == &m_page_table);
+
 		auto result = TRY(create_to_vaddr(page_table, vaddr(), size(), flags()));
 
-		m_page_table.lock();
-
+		LockGuard _(m_page_table);
 		ASSERT(m_page_table.is_page_free(0));
-		for (size_t i = 0; i < result->m_physical_pages.size(); i++)
+		for (size_t offset = 0; offset < size(); offset += PAGE_SIZE)
 		{
-			m_page_table.map_page_at(result->m_physical_pages[i], 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-			memcpy((void*)0, (void*)(vaddr() + i * PAGE_SIZE), PAGE_SIZE);
+			m_page_table.map_page_at(result->m_page_table.physical_address_of(vaddr() + offset), 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
+			memcpy((void*)0, (void*)(vaddr() + offset), PAGE_SIZE);
 		}
 		m_page_table.unmap_page(0);
 
-		m_page_table.unlock();
-
 		return result;
 	}
 
@@ -162,17 +156,14 @@ namespace Kernel
 			return;
 		}
 
-		page_table.lock();
+		LockGuard _(page_table);
 		ASSERT(page_table.is_page_free(0));
-
-		for (size_t i = 0; i < m_physical_pages.size(); i++)
+		for (size_t offset = 0; offset < size(); offset += PAGE_SIZE)
 		{
-			page_table.map_page_at(m_physical_pages[i], 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
+			page_table.map_page_at(m_page_table.physical_address_of(vaddr() + offset), 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
 			memset((void*)0, 0, PAGE_SIZE);
 		}
 		page_table.unmap_page(0);
-
-		page_table.unlock();
 	}
 
 	void VirtualRange::copy_from(size_t offset, const uint8_t* buffer, size_t bytes)
@@ -193,14 +184,14 @@ namespace Kernel
 			return;
 		}
 
-		page_table.lock();
+		LockGuard _(page_table);
 		ASSERT(page_table.is_page_free(0));
 
 		size_t off = offset % PAGE_SIZE;
 		size_t i = offset / PAGE_SIZE;
 
 		// NOTE: we map the first page separately since it needs extra calculations
-		page_table.map_page_at(m_physical_pages[i], 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
+		page_table.map_page_at(m_page_table.physical_address_of(vaddr() + i * PAGE_SIZE), 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
 
 		memcpy((void*)off, buffer, PAGE_SIZE - off);
 
@@ -212,7 +203,7 @@ namespace Kernel
 		{
 			size_t len = BAN::Math::min<size_t>(PAGE_SIZE, bytes);
 
-			page_table.map_page_at(m_physical_pages[i], 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
+			page_table.map_page_at(m_page_table.physical_address_of(vaddr() + i * PAGE_SIZE), 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
 
 			memcpy((void*)0, buffer, len);
 
@@ -221,8 +212,6 @@ namespace Kernel
 			i++;
 		}
 		page_table.unmap_page(0);
-
-		page_table.unlock();
 	}
 
 }

kernel/kernel/Networking/E1000.cpp

@@ -5,7 +5,7 @@
 #include <kernel/MMIO.h>
 #include <kernel/Networking/E1000.h>
 
-#define E1000_GENERAL_MEM_SIZE		(128 * 1024)
+#define DEBUG_E1000 1
 
 #define E1000_REG_CTRL				0x0000
 #define E1000_REG_STATUS			0x0008
@@ -112,7 +112,7 @@ namespace Kernel
 		volatile uint16_t special;
 	} __attribute__((packed));
 
-	BAN::ErrorOr<BAN::UniqPtr<E1000>> E1000::create(const PCIDevice& pci_device)
+	BAN::ErrorOr<BAN::UniqPtr<E1000>> E1000::create(PCI::Device& pci_device)
 	{
 		E1000* e1000 = new E1000();
 		ASSERT(e1000);
@@ -126,42 +126,26 @@ namespace Kernel
 
 	E1000::~E1000()
 	{
-		if (m_bar_type == PCIDevice::BarType::MEM && m_bar_addr)
-			PageTable::kernel().unmap_range(m_bar_addr & PAGE_ADDR_MASK, E1000_GENERAL_MEM_SIZE);
 	}
 
-	BAN::ErrorOr<void> E1000::initialize(const PCIDevice& pci_device)
+	BAN::ErrorOr<void> E1000::initialize(PCI::Device& pci_device)
 	{
-		m_bar_type = pci_device.read_bar_type(0);
-		if (m_bar_type == PCIDevice::BarType::INVAL)
-		{
-			dwarnln("invalid bar0 type");
-			return BAN::Error::from_errno(EINVAL);
-		}
-
-		if (m_bar_type == PCIDevice::BarType::MEM)
-		{
-			uint64_t bar_addr = pci_device.read_bar_address(0);
-
-			vaddr_t page_vaddr = PageTable::kernel().reserve_free_contiguous_pages(E1000_GENERAL_MEM_SIZE / PAGE_SIZE, KERNEL_OFFSET);
-			paddr_t page_paddr = bar_addr & PAGE_ADDR_MASK;
-			PageTable::kernel().map_range_at(page_paddr, page_vaddr, E1000_GENERAL_MEM_SIZE, PageTable::Flags::CacheDisable | PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-
-			m_bar_addr = page_vaddr + (bar_addr % PAGE_SIZE);
-		}
-		else if (m_bar_type == PCIDevice::BarType::IO)
-		{
-			m_bar_addr = pci_device.read_bar_address(0);
-		}
-
+		m_bar_region = TRY(pci_device.allocate_bar_region(0));
 		pci_device.enable_bus_mastering();
 
 		detect_eeprom();
 
 		TRY(read_mac_address());
 		
-		dprintln("E1000 at PCI {}:{}.{}", pci_device.bus(), pci_device.dev(), pci_device.func());
 
+		initialize_rx();
+		initialize_tx();
+
+		enable_link();
+		enable_interrupts();
+		
+#if DEBUG_E1000
+		dprintln("E1000 at PCI {}:{}.{}", pci_device.bus(), pci_device.dev(), pci_device.func());
 		dprintln("  MAC: {2H}:{2H}:{2H}:{2H}:{2H}:{2H}",
 			m_mac_address[0],
 			m_mac_address[1],
@@ -170,52 +154,22 @@ namespace Kernel
 			m_mac_address[4],
 			m_mac_address[5]
 		);
-
-		initialize_rx();
-		initialize_tx();
-
-		enable_link();
-		enable_interrupts();
-		
 		dprintln("  link up: {}", link_up());
 		if (link_up())
 			dprintln("  link speed: {} Mbps", link_speed());
+#endif
 
 		return {};
 	}
 
 	void E1000::write32(uint16_t reg, uint32_t value)
 	{
-		switch (m_bar_type)
-		{
-			case PCIDevice::BarType::MEM:
-				MMIO::write32(m_bar_addr + reg, value);
-				break;
-			case PCIDevice::BarType::IO:
-				IO::outl(m_bar_addr, reg);
-				IO::outl(m_bar_addr + 4, value);
-				break;
-			default:
-				ASSERT_NOT_REACHED();
-		}
+		m_bar_region->write32(reg, value);
 	}
 
 	uint32_t E1000::read32(uint16_t reg)
 	{
-		uint32_t result = 0;
-		switch (m_bar_type)
-		{
-			case PCIDevice::BarType::MEM:
-				result = MMIO::read32(m_bar_addr + reg);
-				break;
-			case PCIDevice::BarType::IO:
-				IO::outl(m_bar_addr, reg);
-				result = IO::inl(m_bar_addr + 4);
-				break;
-			default:
-				ASSERT_NOT_REACHED();
-		}
-		return result;
+		return m_bar_region->read32(reg);
 	}
 
 	void E1000::detect_eeprom()

kernel/kernel/PCI.cpp

@@ -1,61 +1,99 @@
 #include <kernel/IO.h>
+#include <kernel/Memory/PageTable.h>
+#include <kernel/MMIO.h>
 #include <kernel/Networking/E1000.h>
 #include <kernel/PCI.h>
 #include <kernel/Storage/ATAController.h>
 
-#define INVALID 0xFFFF
+#define INVALID_VENDOR 0xFFFF
 #define MULTI_FUNCTION 0x80
 
 #define CONFIG_ADDRESS 0xCF8
 #define CONFIG_DATA 0xCFC
 
-namespace Kernel
+#define DEBUG_PCI 1
+
+namespace Kernel::PCI
 {
 
-	static PCI* s_instance = nullptr;
+	static PCIManager* s_instance = nullptr;
 
-	void PCI::initialize()
-	{
-		ASSERT(s_instance == nullptr);
-		s_instance = new PCI();
-		ASSERT(s_instance);
-		s_instance->check_all_buses();
-		s_instance->initialize_devices();
-	}
-
-	PCI& PCI::get()
-	{
-		ASSERT(s_instance);
-		return *s_instance;
-	}
-
-	static uint32_t read_config_dword(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset)
+	uint32_t PCIManager::read_config_dword(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset)
 	{
+		ASSERT(offset % 4 == 0);
 		uint32_t config_addr = 0x80000000 | ((uint32_t)bus << 16) | ((uint32_t)dev << 11) | ((uint32_t)func << 8) | offset;
 		IO::outl(CONFIG_ADDRESS, config_addr);
 		return IO::inl(CONFIG_DATA);
 	}
 
-	static void write_config_dword(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset, uint32_t value)
+	uint16_t PCIManager::read_config_word(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset)
 	{
+		ASSERT(offset % 2 == 0);
+		uint32_t dword = read_config_dword(bus, dev, func, offset & ~3);
+		return (dword >> ((offset & 3) * 8)) & 0xFFFF;
+	}
+
+	uint8_t PCIManager::read_config_byte(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset)
+	{
+		uint32_t dword = read_config_dword(bus, dev, func, offset & ~3);
+		return (dword >> ((offset & 3) * 8)) & 0xFF;
+	}
+
+	void PCIManager::write_config_dword(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset, uint32_t value)
+	{
+		ASSERT(offset % 4 == 0);
 		uint32_t config_addr = 0x80000000 | ((uint32_t)bus << 16) | ((uint32_t)dev << 11) | ((uint32_t)func << 8) | offset;
 		IO::outl(CONFIG_ADDRESS, config_addr);
 		IO::outl(CONFIG_DATA, value);
 	}
 
+	void PCIManager::write_config_word(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset, uint16_t value)
+	{
+		ASSERT(offset % 2 == 0);
+		uint32_t byte = (offset & 3) * 8;
+		uint32_t temp = read_config_dword(bus, dev, func, offset & ~3);
+		temp &= ~(0xFFFF << byte);
+		temp |= (uint32_t)value << byte;
+		write_config_dword(bus, dev, func, offset & ~3, temp);
+	}
+
+	void PCIManager::write_config_byte(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset, uint8_t value)
+	{
+		uint32_t byte = (offset & 3) * 8;
+		uint32_t temp = read_config_dword(bus, dev, func, offset & ~3);
+		temp &= ~(0xFF << byte);
+		temp |= (uint32_t)value << byte;
+		write_config_dword(bus, dev, func, offset, temp);
+	}
+
 	static uint16_t get_vendor_id(uint8_t bus, uint8_t dev, uint8_t func)
 	{
-		uint32_t dword = read_config_dword(bus, dev, func, 0x00);
+		uint32_t dword = PCIManager::read_config_dword(bus, dev, func, 0x00);
 		return dword & 0xFFFF;
 	}
 
 	static uint8_t get_header_type(uint8_t bus, uint8_t dev, uint8_t func)
 	{
-		uint32_t dword = read_config_dword(bus, dev, func, 0x0C);
+		uint32_t dword = PCIManager::read_config_dword(bus, dev, func, 0x0C);
 		return (dword >> 16) & 0xFF;
 	}
 
-	void PCI::check_function(uint8_t bus, uint8_t dev, uint8_t func)
+	void PCIManager::initialize()
+	{
+		ASSERT(s_instance == nullptr);
+		s_instance = new PCIManager();
+		ASSERT(s_instance);
+		s_instance->check_all_buses();
+		s_instance->initialize_devices();
+	}
+
+	PCIManager& PCIManager::get()
+	{
+		ASSERT(s_instance);
+		return *s_instance;
+	}
+
+	void PCIManager::check_function(uint8_t bus, uint8_t dev, uint8_t func)
 	{
 		MUST(m_devices.emplace_back(bus, dev, func));
 		auto& device = m_devices.back();
@@ -63,29 +101,29 @@ namespace Kernel
 			check_bus(device.read_byte(0x19));
 	}
 
-	void PCI::check_device(uint8_t bus, uint8_t dev)
+	void PCIManager::check_device(uint8_t bus, uint8_t dev)
 	{
-		if (get_vendor_id(bus, dev, 0) == INVALID)
+		if (get_vendor_id(bus, dev, 0) == INVALID_VENDOR)
 			return;
 		
 		check_function(bus, dev, 0);
 		if (get_header_type(bus, dev, 0) & MULTI_FUNCTION)
 			for (uint8_t func = 1; func < 8; func++)
-				if (get_vendor_id(bus, dev, func) != INVALID)
+				if (get_vendor_id(bus, dev, func) != INVALID_VENDOR)
 					check_function(bus, dev, func);
 	}
 
-	void PCI::check_bus(uint8_t bus)
+	void PCIManager::check_bus(uint8_t bus)
 	{
 		for (uint8_t dev = 0; dev < 32; dev++)
 			check_device(bus, dev);
 	}
 
-	void PCI::check_all_buses()
+	void PCIManager::check_all_buses()
 	{
 		if (get_header_type(0, 0, 0) & MULTI_FUNCTION)
 		{
-			for (int func = 0; func < 8 && get_vendor_id(0, 0, func) != INVALID; func++)
+			for (int func = 0; func < 8 && get_vendor_id(0, 0, func) != INVALID_VENDOR; func++)
 				check_bus(func);
 		}
 		else
@@ -94,9 +132,9 @@ namespace Kernel
 		}
 	}
 
-	void PCI::initialize_devices()
+	void PCIManager::initialize_devices()
 	{
-		for (const auto& pci_device : PCI::get().devices())
+		for (auto& pci_device : m_devices)
 		{
 			switch (pci_device.class_code())
 			{
@@ -134,7 +172,144 @@ namespace Kernel
 		}
 	}
 
-	PCIDevice::PCIDevice(uint8_t bus, uint8_t dev, uint8_t func)
+	BAN::ErrorOr<BAN::UniqPtr<BarRegion>> BarRegion::create(PCI::Device& device, uint8_t bar_num)
+	{
+		ASSERT(device.header_type() == 0x00);
+
+		uint32_t command_status = device.read_dword(0x04);
+
+		// disable io/mem space while reading bar
+		device.write_dword(0x04, command_status & ~3);
+
+		uint8_t offset = 0x10 + bar_num * 8;
+
+		uint64_t addr = device.read_dword(offset);
+
+		device.write_dword(offset, 0xFFFFFFFF);
+		uint32_t size = device.read_dword(0x10 + bar_num * 8);
+		size = ~size + 1;
+		device.write_dword(offset, addr);
+
+		// determine bar type
+		BarType type = BarType::INVALID;
+		if (addr & 1)
+		{
+			type = BarType::IO;
+			addr &= 0xFFFFFFFC;
+		}
+		else if ((addr & 0b110) == 0b000)
+		{
+			type = BarType::MEM;
+			addr &= 0xFFFFFFF0;
+		}
+		else if ((addr & 0b110) == 0b100)
+		{
+			type = BarType::MEM;
+			addr &= 0xFFFFFFF0;
+			addr |= (uint64_t)device.read_dword(offset + 8) << 32;
+		}
+
+		if (type == BarType::INVALID)
+		{
+			dwarnln("invalid pci device bar");
+			return BAN::Error::from_errno(EINVAL);
+		}
+
+		auto* region_ptr = new BarRegion(type, addr, size);
+		ASSERT(region_ptr);
+
+		auto region = BAN::UniqPtr<BarRegion>::adopt(region_ptr);
+		TRY(region->initialize());
+
+		// restore old command register and enable correct IO/MEM
+		command_status |= (type == BarType::IO) ? 1 : 2;
+		device.write_dword(0x04, command_status);
+
+#if DEBUG_PCI
+		dprintln("created BAR region for PCI {}:{}.{}",
+			device.bus(),
+			device.dev(),
+			device.func()
+		);
+		dprintln("  type: {}", region->type() == BarType::IO ? "IO" : "MEM");
+		dprintln("  paddr {}", (void*)region->paddr());
+		dprintln("  vaddr {}", (void*)region->vaddr());
+		dprintln("  size  {}", region->size());
+#endif
+
+		return region;
+	}
+
+	BarRegion::BarRegion(BarType type, paddr_t paddr, size_t size)
+		: m_type(type)
+		, m_paddr(paddr)
+		, m_size(size)
+	{ }
+
+	BarRegion::~BarRegion()
+	{
+		if (m_type == BarType::MEM && m_vaddr)
+			PageTable::kernel().unmap_range(m_vaddr, m_size);
+		m_vaddr = 0;		
+	}
+
+	BAN::ErrorOr<void> BarRegion::initialize()
+	{
+		if (m_type == BarType::IO)
+			return {};
+
+		size_t needed_pages = BAN::Math::div_round_up<size_t>(m_size, PAGE_SIZE);
+		m_vaddr = PageTable::kernel().reserve_free_contiguous_pages(needed_pages, KERNEL_OFFSET);
+		if (m_vaddr == 0)
+			return BAN::Error::from_errno(ENOMEM);
+		PageTable::kernel().map_range_at(m_paddr, m_vaddr, m_size, PageTable::Flags::CacheDisable | PageTable::Flags::ReadWrite | PageTable::Flags::Present);
+
+		return {};
+	}
+
+	void BarRegion::write8(off_t reg, uint8_t val)
+	{
+		if (m_type == BarType::IO)
+			return IO::outb(m_vaddr + reg, val);
+		MMIO::write8(m_vaddr + reg, val);
+	}
+
+	void BarRegion::write16(off_t reg, uint16_t val)
+	{
+		if (m_type == BarType::IO)
+			return IO::outw(m_vaddr + reg, val);
+		MMIO::write16(m_vaddr + reg, val);
+	}
+
+	void BarRegion::write32(off_t reg, uint32_t val)
+	{
+		if (m_type == BarType::IO)
+			return IO::outl(m_vaddr + reg, val);
+		MMIO::write32(m_vaddr + reg, val);
+	}
+
+	uint8_t BarRegion::read8(off_t reg)
+	{
+		if (m_type == BarType::IO)
+			return IO::inb(m_vaddr + reg);
+		return MMIO::read8(m_vaddr + reg);
+	}
+
+	uint16_t BarRegion::read16(off_t reg)
+	{
+		if (m_type == BarType::IO)
+			return IO::inw(m_vaddr + reg);
+		return MMIO::read16(m_vaddr + reg);
+	}
+
+	uint32_t BarRegion::read32(off_t reg)
+	{
+		if (m_type == BarType::IO)
+			return IO::inl(m_vaddr + reg);
+		return MMIO::read32(m_vaddr + reg);
+	}
+
+	PCI::Device::Device(uint8_t bus, uint8_t dev, uint8_t func)
 		: m_bus(bus), m_dev(dev), m_func(func)
 	{
 		uint32_t type = read_word(0x0A);
@@ -142,87 +317,101 @@ namespace Kernel
 		m_subclass    = (uint8_t)(type);
 		m_prog_if     = read_byte(0x09);
 		m_header_type = read_byte(0x0E);
+
+		enumerate_capabilites();
 	}
 
-	uint32_t PCIDevice::read_dword(uint8_t offset) const
+	uint32_t PCI::Device::read_dword(uint8_t offset) const
 	{
-		ASSERT((offset & 0x03) == 0);
-		return read_config_dword(m_bus, m_dev, m_func, offset);
+		ASSERT(offset % 4 == 0);
+		return PCIManager::read_config_dword(m_bus, m_dev, m_func, offset);
 	}
 
-	uint16_t PCIDevice::read_word(uint8_t offset) const
+	uint16_t PCI::Device::read_word(uint8_t offset) const
 	{
-		ASSERT((offset & 0x01) == 0);
-		uint32_t dword = read_config_dword(m_bus, m_dev, m_func, offset & 0xFC);
-		return (uint16_t)(dword >> (8 * (offset & 0x03)));
+		ASSERT(offset % 2 == 0);
+		return PCIManager::read_config_word(m_bus, m_dev, m_func, offset);
 	}
 
-	uint8_t PCIDevice::read_byte(uint8_t offset) const
+	uint8_t PCI::Device::read_byte(uint8_t offset) const
 	{
-		uint32_t dword = read_config_dword(m_bus, m_dev, m_func, offset & 0xFC);
-		return (uint8_t)(dword >> (8 * (offset & 0x03)));
+		return PCIManager::read_config_byte(m_bus, m_dev, m_func, offset);
 	}
 
-	void PCIDevice::write_dword(uint8_t offset, uint32_t value) const
+	void PCI::Device::write_dword(uint8_t offset, uint32_t value)
 	{
-		ASSERT((offset & 0x03) == 0);
-		write_config_dword(m_bus, m_dev, m_func, offset, value);
+		ASSERT(offset % 4 == 0);
+		PCIManager::write_config_dword(m_bus, m_dev, m_func, offset, value);
 	}
 
-	PCIDevice::BarType PCIDevice::read_bar_type(uint8_t bar) const
+	void PCI::Device::write_word(uint8_t offset, uint16_t value)
 	{
-		ASSERT(m_header_type == 0x00);
-		ASSERT(bar <= 5);
-
-		uint32_t type = read_dword(0x10 + bar * 4) & 0b111;
-		if (type & 1)
-			return BarType::IO;
-		type >>= 1;
-		if (type == 0x0 || type == 0x2)
-			return BarType::MEM;
-		return BarType::INVAL;
+		ASSERT(offset % 2 == 0);
+		PCIManager::write_config_word(m_bus, m_dev, m_func, offset, value);
 	}
 
-	uint64_t PCIDevice::read_bar_address(uint8_t bar) const
+	void PCI::Device::write_byte(uint8_t offset, uint8_t value)
 	{
-		ASSERT(m_header_type == 0x00);
-		ASSERT(bar <= 5);
-
-		uint64_t address = read_dword(0x10 + bar * 4);
-		if (address & 1)
-			return address & 0xFFFFFFFC;
-		if ((address & 0b110) == 0b100)
-			address |= (uint64_t)read_dword(0x10 + bar * 4 + 4) << 32;
-		return address & 0xFFFFFFFFFFFFFFF0;
+		PCIManager::write_config_byte(m_bus, m_dev, m_func, offset, value);
 	}
 
-	void PCIDevice::enable_bus_mastering() const
+	BAN::ErrorOr<BAN::UniqPtr<BarRegion>> PCI::Device::allocate_bar_region(uint8_t bar_num)
+	{
+		return BarRegion::create(*this, bar_num);
+	}
+
+	void PCI::Device::enumerate_capabilites()
+	{
+		uint16_t status = read_word(0x06);
+		if (!(status & (1 << 4)))
+			return;
+
+		uint8_t capabilities = read_byte(0x34) & 0xFC;
+		while (capabilities)
+		{
+			uint16_t next = read_word(capabilities);
+			dprintln("  cap {2H}", next & 0xFF);
+			capabilities = (next >> 8) & 0xFC;
+		}
+	}
+
+	void PCI::Device::enable_bus_mastering()
 	{
 		write_dword(0x04, read_dword(0x04) | 1u << 2);
 	}
 
-	void PCIDevice::disable_bus_mastering() const
+	void PCI::Device::disable_bus_mastering()
 	{
 		write_dword(0x04, read_dword(0x04) & ~(1u << 2));
 
 	}
 
-	void PCIDevice::enable_memory_space() const
+	void PCI::Device::enable_memory_space()
 	{
 		write_dword(0x04, read_dword(0x04) | 1u << 1);
 	}
 
-	void PCIDevice::disable_memory_space() const
+	void PCI::Device::disable_memory_space()
 	{
 		write_dword(0x04, read_dword(0x04) & ~(1u << 1));
 	}
 
-	void PCIDevice::enable_pin_interrupts() const
+	void PCI::Device::enable_io_space()
+	{
+		write_dword(0x04, read_dword(0x04) | 1u << 0);
+	}
+
+	void PCI::Device::disable_io_space()
+	{
+		write_dword(0x04, read_dword(0x04) & ~(1u << 0));
+	}
+
+	void PCI::Device::enable_pin_interrupts()
 	{
 		write_dword(0x04, read_dword(0x04) | 1u << 10);
 	}
 
-	void PCIDevice::disable_pin_interrupts() const
+	void PCI::Device::disable_pin_interrupts()
 	{
 		write_dword(0x04, read_dword(0x04) & ~(1u << 10));
 	}

kernel/kernel/Process.cpp

@@ -99,7 +99,7 @@ namespace Kernel
 
 	BAN::ErrorOr<Process*> Process::create_userspace(const Credentials& credentials, BAN::StringView path)
 	{
-		auto elf = TRY(load_elf_for_exec(credentials, path, "/"sv, {}));
+		auto elf = TRY(load_elf_for_exec(credentials, path, "/"sv));
 
 		auto* process = create_process(credentials, 0);
 		MUST(process->m_working_directory.push_back('/'));
@@ -114,27 +114,35 @@ namespace Kernel
 		elf.clear();
 
 		char** argv = nullptr;
-		char** envp = nullptr;
 		{
 			PageTableScope _(process->page_table());
 
-			argv = (char**)MUST(process->sys_alloc(sizeof(char**) * 2));
-			argv[0] = (char*)MUST(process->sys_alloc(path.size() + 1));
-			memcpy(argv[0], path.data(), path.size());
-			argv[0][path.size()] = '\0';
-			argv[1] = nullptr;
+			size_t needed_bytes = sizeof(char*) * 2 + path.size() + 1;
+			if (auto rem = needed_bytes % PAGE_SIZE)
+				needed_bytes += PAGE_SIZE - rem;
 
-			BAN::StringView env1 = "PATH=/bin:/usr/bin"sv;
-			envp = (char**)MUST(process->sys_alloc(sizeof(char**) * 2));
-			envp[0] = (char*)MUST(process->sys_alloc(env1.size() + 1));
-			memcpy(envp[0], env1.data(), env1.size());
-			envp[0][env1.size()] = '\0';
-			envp[1] = nullptr;
+			auto argv_range = MUST(VirtualRange::create_to_vaddr_range(
+				process->page_table(),
+				0x400000, KERNEL_OFFSET,
+				needed_bytes,
+				PageTable::Flags::UserSupervisor | PageTable::Flags::ReadWrite | PageTable::Flags::Present
+			));
+			argv_range->set_zero();
+
+			uintptr_t temp = argv_range->vaddr() + sizeof(char*) * 2;
+			argv_range->copy_from(0, (uint8_t*)&temp, sizeof(char*));			
+
+			temp = 0;
+			argv_range->copy_from(sizeof(char*), (uint8_t*)&temp, sizeof(char*));	
+
+			argv_range->copy_from(sizeof(char*) * 2, (const uint8_t*)path.data(), path.size());
+
+			MUST(process->m_mapped_ranges.emplace_back(false, BAN::move(argv_range)));
 		}
 
 		process->m_userspace_info.argc = 1;
 		process->m_userspace_info.argv = argv;
-		process->m_userspace_info.envp = envp;
+		process->m_userspace_info.envp = nullptr;
 
 		auto* thread = MUST(Thread::create_userspace(process));
 		process->add_thread(thread);
@@ -157,8 +165,6 @@ namespace Kernel
 	Process::~Process()
 	{
 		ASSERT(m_threads.empty());
-		ASSERT(m_fixed_width_allocators.empty());
-		ASSERT(!m_general_allocator);
 		ASSERT(m_mapped_ranges.empty());
 		ASSERT(m_exit_status.waiting == 0);
 		ASSERT(&PageTable::current() != m_page_table.ptr());
@@ -193,10 +199,6 @@ namespace Kernel
 
 		// NOTE: We must unmap ranges while the page table is still alive
 		m_mapped_ranges.clear();
-
-		// NOTE: We must clear allocators while the page table is still alive
-		m_fixed_width_allocators.clear();
-		m_general_allocator.clear();
 	}
 
 	void Process::on_thread_exit(Thread& thread)
@@ -273,7 +275,7 @@ namespace Kernel
 		return 0;
 	}
 
-	BAN::ErrorOr<BAN::UniqPtr<LibELF::ELF>> Process::load_elf_for_exec(const Credentials& credentials, BAN::StringView file_path, const BAN::String& cwd, const BAN::Vector<BAN::StringView>& path_env)
+	BAN::ErrorOr<BAN::UniqPtr<LibELF::ELF>> Process::load_elf_for_exec(const Credentials& credentials, BAN::StringView file_path, const BAN::String& cwd)
 	{
 		if (file_path.empty())
 			return BAN::Error::from_errno(ENOENT);
@@ -281,44 +283,13 @@ namespace Kernel
 		BAN::String absolute_path;
 
 		if (file_path.front() == '/')
-		{
-			// We have an absolute path
 			TRY(absolute_path.append(file_path));
-		}
-		else if (file_path.front() == '.' || file_path.contains('/'))
+		else
 		{
-			// We have a relative path
 			TRY(absolute_path.append(cwd));
 			TRY(absolute_path.push_back('/'));
 			TRY(absolute_path.append(file_path));
 		}
-		else
-		{
-			// We have neither relative or absolute path,
-			// search from PATH environment
-			for (auto path_part : path_env)
-			{
-				if (path_part.empty())
-					continue;
-
-				if (path_part.front() != '/')
-				{
-					TRY(absolute_path.append(cwd));
-					TRY(absolute_path.push_back('/'));
-				}
-				TRY(absolute_path.append(path_part));
-				TRY(absolute_path.push_back('/'));
-				TRY(absolute_path.append(file_path));
-
-				if (!VirtualFileSystem::get().file_from_absolute_path(credentials, absolute_path, O_EXEC).is_error())
-					break;
-
-				absolute_path.clear();
-			}
-
-			if (absolute_path.empty())
-				return BAN::Error::from_errno(ENOENT);
-		}
 
 		auto file = TRY(VirtualFileSystem::get().file_from_absolute_path(credentials, absolute_path, O_EXEC));
 
@@ -358,20 +329,10 @@ namespace Kernel
 		OpenFileDescriptorSet open_file_descriptors(m_credentials);
 		TRY(open_file_descriptors.clone_from(m_open_file_descriptors));
 
-		BAN::Vector<BAN::UniqPtr<VirtualRange>> mapped_ranges;
+		BAN::Vector<MappedRange> mapped_ranges;
 		TRY(mapped_ranges.reserve(m_mapped_ranges.size()));
 		for (auto& mapped_range : m_mapped_ranges)
-			MUST(mapped_ranges.push_back(TRY(mapped_range->clone(*page_table))));
-
-		BAN::Vector<BAN::UniqPtr<FixedWidthAllocator>> fixed_width_allocators;
-		TRY(fixed_width_allocators.reserve(m_fixed_width_allocators.size()));
-		for (auto& allocator : m_fixed_width_allocators)
-			if (allocator->allocations() > 0)
-				MUST(fixed_width_allocators.push_back(TRY(allocator->clone(*page_table))));
-
-		BAN::UniqPtr<GeneralAllocator> general_allocator;
-		if (m_general_allocator)
-			general_allocator = TRY(m_general_allocator->clone(*page_table));
+			MUST(mapped_ranges.emplace_back(mapped_range.can_be_unmapped, TRY(mapped_range.range->clone(*page_table))));
 
 		Process* forked = create_process(m_credentials, m_pid, m_sid, m_pgrp);
 		forked->m_controlling_terminal = m_controlling_terminal;
@@ -379,8 +340,6 @@ namespace Kernel
 		forked->m_page_table = BAN::move(page_table);
 		forked->m_open_file_descriptors = BAN::move(open_file_descriptors);
 		forked->m_mapped_ranges = BAN::move(mapped_ranges);
-		forked->m_fixed_width_allocators = BAN::move(fixed_width_allocators);
-		forked->m_general_allocator = BAN::move(general_allocator);
 		forked->m_is_userspace = m_is_userspace;
 		forked->m_userspace_info = m_userspace_info;
 		forked->m_has_called_exec = false;
@@ -404,14 +363,9 @@ namespace Kernel
 			for (int i = 0; argv && argv[i]; i++)
 				TRY(str_argv.emplace_back(argv[i]));
 
-			BAN::Vector<BAN::StringView> path_env;
 			BAN::Vector<BAN::String> str_envp;
 			for (int i = 0; envp && envp[i]; i++)
-			{
 				TRY(str_envp.emplace_back(envp[i]));
-				if (strncmp(envp[i], "PATH=", 5) == 0)
-					path_env = TRY(BAN::StringView(envp[i]).substring(5).split(':'));
-			}
 
 			BAN::String working_directory;
 
@@ -420,14 +374,12 @@ namespace Kernel
 				TRY(working_directory.append(m_working_directory));
 			}
 
-			auto elf = TRY(load_elf_for_exec(m_credentials, path, working_directory, path_env));
+			auto elf = TRY(load_elf_for_exec(m_credentials, path, working_directory));
 
 			LockGuard lock_guard(m_lock);
 
 			m_open_file_descriptors.close_cloexec();
 
-			m_fixed_width_allocators.clear();
-			m_general_allocator.clear();
 			m_mapped_ranges.clear();
 
 			load_elf_to_memory(*elf);
@@ -444,27 +396,46 @@ namespace Kernel
 			ASSERT(&Process::current() == this);
 
 			// allocate memory on the new process for arguments and environment
-			{
-				LockGuard _(page_table());
-
-				m_userspace_info.argv = (char**)MUST(sys_alloc(sizeof(char**) * (str_argv.size() + 1)));
-				for (size_t i = 0; i < str_argv.size(); i++)
+			auto create_range =
+				[&](const auto& container) -> BAN::UniqPtr<VirtualRange>
 				{
-					m_userspace_info.argv[i] = (char*)MUST(sys_alloc(str_argv[i].size() + 1));
-					memcpy(m_userspace_info.argv[i], str_argv[i].data(), str_argv[i].size());
-					m_userspace_info.argv[i][str_argv[i].size()] = '\0';
-				}
-				m_userspace_info.argv[str_argv.size()] = nullptr;
+					size_t bytes = sizeof(char*);
+					for (auto& elem : container)
+						bytes += sizeof(char*) + elem.size() + 1;
 
-				m_userspace_info.envp = (char**)MUST(sys_alloc(sizeof(char**) * (str_envp.size() + 1)));
-				for (size_t i = 0; i < str_envp.size(); i++)
-				{
-					m_userspace_info.envp[i] = (char*)MUST(sys_alloc(str_envp[i].size() + 1));
-					memcpy(m_userspace_info.envp[i], str_envp[i].data(), str_envp[i].size());
-					m_userspace_info.envp[i][str_envp[i].size()] = '\0';
-				}
-				m_userspace_info.envp[str_envp.size()] = nullptr;
-			}
+					if (auto rem = bytes % PAGE_SIZE)
+						bytes += PAGE_SIZE - rem;
+
+					auto range = MUST(VirtualRange::create_to_vaddr_range(
+						page_table(),
+						0x400000, KERNEL_OFFSET,
+						bytes,
+						PageTable::Flags::UserSupervisor | PageTable::Flags::ReadWrite | PageTable::Flags::Present
+					));
+					range->set_zero();
+
+					size_t data_offset = sizeof(char*) * (container.size() + 1);
+					for (size_t i = 0; i < container.size(); i++)
+					{
+						uintptr_t ptr_addr = range->vaddr() + data_offset;
+						range->copy_from(sizeof(char*) * i, (const uint8_t*)&ptr_addr, sizeof(char*));
+						range->copy_from(data_offset, (const uint8_t*)container[i].data(), container[i].size());
+						data_offset += container[i].size() + 1;
+					}
+
+					uintptr_t null = 0;
+					range->copy_from(sizeof(char*) * container.size(), (const uint8_t*)&null, sizeof(char*));
+
+					return BAN::move(range);
+				};
+
+			auto argv_range = create_range(str_argv);
+			m_userspace_info.argv = (char**)argv_range->vaddr();
+			MUST(m_mapped_ranges.emplace_back(false, BAN::move(argv_range)));
+
+			auto envp_range = create_range(str_envp);
+			m_userspace_info.envp = (char**)envp_range->vaddr();
+			MUST(m_mapped_ranges.emplace_back(false, BAN::move(envp_range)));
 
 			m_userspace_info.argc = str_argv.size();
 
@@ -538,13 +509,6 @@ namespace Kernel
 		return 0;
 	}
 
-	BAN::ErrorOr<long> Process::sys_setenvp(char** envp)
-	{
-		LockGuard _(m_lock);
-		m_userspace_info.envp = envp;
-		return 0;
-	}
-
 	void Process::load_elf_to_memory(LibELF::ELF& elf)
 	{
 		ASSERT(elf.is_native());
@@ -583,9 +547,11 @@ namespace Kernel
 
 				{
 					LockGuard _(m_lock);
-					MUST(m_mapped_ranges.push_back(MUST(VirtualRange::create_to_vaddr(page_table(), page_start * PAGE_SIZE, page_count * PAGE_SIZE, flags))));
-					m_mapped_ranges.back()->set_zero();
-					m_mapped_ranges.back()->copy_from(elf_program_header.p_vaddr % PAGE_SIZE, elf.data() + elf_program_header.p_offset, elf_program_header.p_filesz);
+					auto range = MUST(VirtualRange::create_to_vaddr(page_table(), page_start * PAGE_SIZE, page_count * PAGE_SIZE, flags));
+					range->set_zero();
+					range->copy_from(elf_program_header.p_vaddr % PAGE_SIZE, elf.data() + elf_program_header.p_offset, elf_program_header.p_filesz);
+
+					MUST(m_mapped_ranges.emplace_back(false, BAN::move(range)));
 				}
 
 				page_table().unlock();
@@ -811,90 +777,66 @@ namespace Kernel
 		return (long)buffer;
 	}
 
-	static constexpr size_t allocator_size_for_allocation(size_t value)
+	BAN::ErrorOr<long> Process::sys_mmap(const sys_mmap_t& args)
 	{
-		if (value <= 256) {
-			if (value <= 64)
-				return 64;
-			else
-				return 256;
-		} else {
-			if (value <= 1024)
-				return 1024;
-			else
-				return 4096;
-		}
-	}
+		if (args.prot != PROT_NONE && args.prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
+			return BAN::Error::from_errno(EINVAL);
 
-	BAN::ErrorOr<long> Process::sys_alloc(size_t bytes)
-	{
-		vaddr_t address = 0;
+		PageTable::flags_t flags = PageTable::Flags::UserSupervisor;
+		if (args.prot & PROT_READ)
+			flags |= PageTable::Flags::Present;
+		if (args.prot & PROT_WRITE)
+			flags |= PageTable::Flags::ReadWrite | PageTable::Flags::Present;
+		if (args.prot & PROT_EXEC)
+			flags |= PageTable::Flags::Execute | PageTable::Flags::Present;
 
-		if (bytes <= PAGE_SIZE)
+		if (args.flags == (MAP_ANONYMOUS | MAP_PRIVATE))
 		{
-			// Do fixed width allocation
-			size_t allocation_size = allocator_size_for_allocation(bytes);
-			ASSERT(bytes <= allocation_size);
-			ASSERT(allocation_size <= PAGE_SIZE);
+			if (args.addr != nullptr)
+				return BAN::Error::from_errno(ENOTSUP);
+			if (args.off != 0)
+				return BAN::Error::from_errno(EINVAL);
+			if (args.len % PAGE_SIZE != 0)
+				return BAN::Error::from_errno(EINVAL);
+
+			auto range = TRY(VirtualRange::create_to_vaddr_range(
+				page_table(),
+				0x400000, KERNEL_OFFSET,
+				args.len,
+				PageTable::Flags::UserSupervisor | PageTable::Flags::ReadWrite | PageTable::Flags::Present
+			));
+			range->set_zero();
 
 			LockGuard _(m_lock);
-
-			bool needs_new_allocator { true };
-
-			for (auto& allocator : m_fixed_width_allocators)
-			{
-				if (allocator->allocation_size() == allocation_size && allocator->allocations() < allocator->max_allocations())
-				{
-					address = allocator->allocate();
-					needs_new_allocator = false;
-					break;
-				}
-			}
-
-			if (needs_new_allocator)
-			{
-				auto allocator = TRY(FixedWidthAllocator::create(page_table(), allocation_size));
-				TRY(m_fixed_width_allocators.push_back(BAN::move(allocator)));
-				address = m_fixed_width_allocators.back()->allocate();
-			}
-		}
-		else
-		{
-			LockGuard _(m_lock);
-
-			if (!m_general_allocator)
-				m_general_allocator = TRY(GeneralAllocator::create(page_table(), 0x400000));
-
-			address = m_general_allocator->allocate(bytes);
+			TRY(m_mapped_ranges.emplace_back(true, BAN::move(range)));
+			return m_mapped_ranges.back().range->vaddr();
 		}
 
-		if (address == 0)
-			return BAN::Error::from_errno(ENOMEM);
-		return address;
+		return BAN::Error::from_errno(ENOTSUP);
 	}
 
-	BAN::ErrorOr<long> Process::sys_free(void* ptr)
+	BAN::ErrorOr<long> Process::sys_munmap(void* addr, size_t len)
 	{
+		if (len == 0)
+			return BAN::Error::from_errno(EINVAL);
+
+		vaddr_t vaddr = (vaddr_t)addr;
+		if (vaddr % PAGE_SIZE != 0)
+			return BAN::Error::from_errno(EINVAL);
+
 		LockGuard _(m_lock);
 
-		for (size_t i = 0; i < m_fixed_width_allocators.size(); i++)
+		for (size_t i = 0; i < m_mapped_ranges.size(); i++)
 		{
-			auto& allocator = m_fixed_width_allocators[i];
-			if (allocator->deallocate((vaddr_t)ptr))
-			{
-				// TODO: This might be too much. Maybe we should only
-				//       remove allocators when we have low memory... ?
-				if (allocator->allocations() == 0)
-					m_fixed_width_allocators.remove(i);
-				return 0;
-			}
+			if (!m_mapped_ranges[i].can_be_unmapped)
+				continue;
+			auto& range = m_mapped_ranges[i].range;
+			if (vaddr + len < range->vaddr() || vaddr >= range->vaddr() + range->size())
+				continue;
+			m_mapped_ranges.remove(i);
 		}
 
-		if (m_general_allocator && m_general_allocator->deallocate((vaddr_t)ptr))
-			return 0;
-
-		dwarnln("free called on pointer that was not allocated");
-		return BAN::Error::from_errno(EINVAL);
+		return 0;
 	}
 
 	BAN::ErrorOr<long> Process::sys_termid(char* buffer) const

kernel/kernel/Storage/ATAController.cpp

@@ -11,7 +11,7 @@
 namespace Kernel
 {
 
-	BAN::ErrorOr<BAN::RefPtr<ATAController>> ATAController::create(const PCIDevice& device)
+	BAN::ErrorOr<BAN::RefPtr<ATAController>> ATAController::create(const PCI::Device& device)
 	{
 		ATAController* controller = new ATAController();
 		if (controller == nullptr)
@@ -50,7 +50,7 @@ namespace Kernel
 		: m_rdev(makedev(DevFileSystem::get().get_next_dev(), 0))
 	{ }
 
-	BAN::ErrorOr<void> ATAController::initialize(const PCIDevice& pci_device)
+	BAN::ErrorOr<void> ATAController::initialize(const PCI::Device& pci_device)
 	{
 		struct Bus
 		{

kernel/kernel/Syscall.cpp

@@ -32,7 +32,9 @@ namespace Kernel
 			return 0;
 		}
 
+#if __enable_sse
 		Thread::current().save_sse();
+#endif
 
 		asm volatile("sti");
 
@@ -68,12 +70,6 @@ namespace Kernel
 		case SYS_OPENAT:
 			ret = Process::current().sys_openat((int)arg1, (const char*)arg2, (int)arg3, (mode_t)arg4);
 			break;
-		case SYS_ALLOC:
-			ret = Process::current().sys_alloc((size_t)arg1);
-			break;
-		case SYS_FREE:
-			ret = Process::current().sys_free((void*)arg1);
-			break;
 		case SYS_SEEK:
 			ret = Process::current().sys_seek((int)arg1, (long)arg2, (int)arg3);
 			break;
@@ -101,9 +97,6 @@ namespace Kernel
 		case SYS_FSTAT:
 			ret = Process::current().sys_fstat((int)arg1, (struct stat*)arg2);
 			break;
-		case SYS_SETENVP:
-			ret = Process::current().sys_setenvp((char**)arg1);
-			break;
 		case SYS_READ_DIR_ENTRIES:
 			ret = Process::current().sys_read_dir_entries((int)arg1, (API::DirectoryEntryList*)arg2, (size_t)arg3);
 			break;
@@ -194,6 +187,12 @@ namespace Kernel
 		case SYS_SYNC:
 			ret = Process::current().sys_sync();
 			break;
+		case SYS_MMAP:
+			ret = Process::current().sys_mmap(*(const sys_mmap_t*)arg1);
+			break;
+		case SYS_MUNMAP:
+			ret = Process::current().sys_munmap((void*)arg1, (size_t)arg2);
+			break;
 		default:
 			dwarnln("Unknown syscall {}", syscall);
 			break;
@@ -205,7 +204,10 @@ namespace Kernel
 			Kernel::panic("Kernel error while returning to userspace {}", ret.error());
 
 		ASSERT(Kernel::Thread::current().state() == Kernel::Thread::State::Executing);
+
+#if __enable_sse
 		Thread::current().load_sse();
+#endif
 
 		if (ret.is_error())
 			return -ret.error().get_error_code();

kernel/kernel/kernel.cpp

@@ -167,7 +167,7 @@ static void init2(void*)
 
 	DevFileSystem::get().initialize_device_updater();
 
-	PCI::initialize();
+	PCI::PCIManager::initialize();
 	dprintln("PCI initialized");
 
 	VirtualFileSystem::initialize(cmdline.root);

kernel/kernel/lai_host.cpp

@@ -0,0 +1,150 @@
+#include <kernel/ACPI.h>
+#include <kernel/IO.h>
+#include <kernel/Memory/kmalloc.h>
+#include <kernel/Memory/PageTable.h>
+#include <kernel/PCI.h>
+#include <kernel/Timer/Timer.h>
+
+#include <lai/host.h>
+
+using namespace Kernel;
+
+void* laihost_malloc(size_t size)
+{
+	return kmalloc(size);
+}
+
+void* laihost_realloc(void* ptr, size_t newsize, size_t oldsize)
+{
+	if (ptr == nullptr)
+		return laihost_malloc(newsize);
+
+	void* new_ptr = laihost_malloc(newsize);
+	if (new_ptr == nullptr)
+		return nullptr;
+
+	memcpy(new_ptr, ptr, BAN::Math::min(newsize, oldsize));
+	kfree(ptr);
+
+	return new_ptr;
+}
+
+void laihost_free(void* ptr, size_t)
+{
+	kfree(ptr);
+}
+
+void laihost_log(int level, const char* msg)
+{
+	if (level == LAI_DEBUG_LOG)
+		dprintln(msg);
+	else if (level == LAI_WARN_LOG)
+		dwarnln(msg);
+	else
+		ASSERT_NOT_REACHED();
+}
+
+void laihost_panic(const char* msg)
+{
+	Kernel::panic(msg);
+}
+
+void* laihost_scan(const char* sig, size_t index)
+{
+	ASSERT(index == 0);
+	return (void*)ACPI::get().get_header(sig);
+}
+
+void* laihost_map(size_t address, size_t count)
+{
+	size_t needed_pages = range_page_count(address, count);
+	vaddr_t vaddr = PageTable::kernel().reserve_free_contiguous_pages(needed_pages, KERNEL_OFFSET);
+	ASSERT(vaddr);
+
+	PageTable::kernel().map_range_at(address & PAGE_ADDR_MASK, vaddr, needed_pages * PAGE_SIZE, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
+
+	return (void*)(vaddr + (address % PAGE_SIZE));
+}
+
+void laihost_unmap(void* ptr, size_t count)
+{
+	PageTable::kernel().unmap_range((vaddr_t)ptr, count);
+}
+
+void laihost_outb(uint16_t port, uint8_t val)
+{
+	IO::outb(port, val);
+}
+
+void laihost_outw(uint16_t port, uint16_t val)
+{
+	IO::outw(port, val);
+}
+
+void laihost_outd(uint16_t port, uint32_t val)
+{
+	IO::outl(port, val);
+}
+
+uint8_t laihost_inb(uint16_t port)
+{
+	return IO::inb(port);
+}
+
+uint16_t laihost_inw(uint16_t port)
+{
+	return IO::inw(port);
+}
+
+uint32_t laihost_ind(uint16_t port)
+{
+	return IO::inl(port);
+}
+
+void laihost_pci_writeb(uint16_t seg, uint8_t bus, uint8_t slot, uint8_t fun, uint16_t offset, uint8_t val)
+{
+	ASSERT(seg == 0);
+	PCI::PCIManager::write_config_byte(bus, slot, fun, offset, val);
+}
+
+void laihost_pci_writew(uint16_t seg, uint8_t bus, uint8_t slot, uint8_t fun, uint16_t offset, uint16_t val)
+{
+	ASSERT(seg == 0);
+	PCI::PCIManager::write_config_word(bus, slot, fun, offset, val);
+}
+
+void laihost_pci_writed(uint16_t seg, uint8_t bus, uint8_t slot, uint8_t fun, uint16_t offset, uint32_t val)
+{
+	ASSERT(seg == 0);
+	PCI::PCIManager::write_config_dword(bus, slot, fun, offset, val);
+}
+
+uint8_t laihost_pci_readb(uint16_t seg, uint8_t bus, uint8_t slot, uint8_t fun, uint16_t offset)
+{
+	ASSERT(seg == 0);
+	return PCI::PCIManager::read_config_byte(bus, slot, fun, offset);
+}
+
+uint16_t laihost_pci_readw(uint16_t seg, uint8_t bus, uint8_t slot, uint8_t fun, uint16_t offset)
+{
+	ASSERT(seg == 0);
+	return PCI::PCIManager::read_config_word(bus, slot, fun, offset);
+
+}
+
+uint32_t laihost_pci_readd(uint16_t seg, uint8_t bus, uint8_t slot, uint8_t fun, uint16_t offset)
+{
+	ASSERT(seg == 0);
+	return PCI::PCIManager::read_config_dword(bus, slot, fun, offset);
+}
+
+void laihost_sleep(uint64_t ms)
+{
+	SystemTimer::get().sleep(ms);
+}
+
+uint64_t laihost_timer(void)
+{
+	auto time = SystemTimer::get().time_since_boot();
+	return (1'000'000'000ull * time.tv_sec + time.tv_nsec) / 100;
+}

kernel/lai

@@ -0,0 +1 @@
+Subproject commit a228465314ee3a542f62d4bdefeb8fbe2b48da41

libc/CMakeLists.txt

@@ -7,12 +7,14 @@ set(LIBC_SOURCES
 	ctype.cpp
 	dirent.cpp
 	fcntl.cpp
+	malloc.cpp
 	printf_impl.cpp
 	pwd.cpp
 	signal.cpp
 	stdio.cpp
 	stdlib.cpp
 	string.cpp
+	sys/mman.cpp
 	sys/stat.cpp
 	sys/wait.cpp
 	termios.cpp

libc/include/sys/mman.h

@@ -46,6 +46,16 @@ struct posix_typed_mem_info
 	size_t posix_tmi_length;	/* Maximum length which may be allocated from a typed memory object. */
 };
 
+struct sys_mmap_t
+{
+	void* addr;
+	size_t len;
+	int prot;
+	int flags;
+	int fildes;
+	off_t off;
+};
+
 int		mlock(const void* addr, size_t len);
 int		mlockall(int flags);
 void*	mmap(void* addr, size_t len, int prot, int flags, int fildes, off_t off);

libc/include/sys/syscall.h

@@ -12,9 +12,6 @@ __BEGIN_DECLS
 #define SYS_CLOSE 5
 #define SYS_OPEN 6
 #define SYS_OPENAT 7
-#define SYS_ALLOC 8
-#define SYS_REALLOC 9
-#define SYS_FREE 10
 #define SYS_SEEK 11
 #define SYS_TELL 12
 #define SYS_GET_TERMIOS 13
@@ -24,7 +21,6 @@ __BEGIN_DECLS
 #define SYS_SLEEP 17
 #define SYS_WAIT 18
 #define SYS_FSTAT 19
-#define SYS_SETENVP 20
 #define SYS_READ_DIR_ENTRIES 21
 #define SYS_SET_UID 22
 #define SYS_SET_GID 23
@@ -55,6 +51,8 @@ __BEGIN_DECLS
 #define SYS_FSTATAT 48
 #define SYS_STAT 49 // stat/lstat
 #define SYS_SYNC 50
+#define SYS_MMAP 51
+#define SYS_MUNMAP 52
 
 __END_DECLS
 

libc/malloc.cpp

@@ -0,0 +1,222 @@
+#include <assert.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+static consteval size_t log_size_t(size_t value, size_t base)
+{
+	size_t result = 0;
+	while (value /= base)
+		result++;
+	return result;
+}
+
+static constexpr size_t s_malloc_pool_size_initial = 4096;
+static constexpr size_t s_malloc_pool_size_multiplier = 2;
+static constexpr size_t s_malloc_pool_count = sizeof(size_t) * 8 - log_size_t(s_malloc_pool_size_initial, s_malloc_pool_size_multiplier);
+static constexpr size_t s_malloc_default_align = 16;
+
+struct malloc_node_t
+{
+	bool allocated;
+	size_t size;
+	uint8_t data[0];
+
+	size_t data_size() const { return size - sizeof(malloc_node_t); }
+	malloc_node_t* next() { return (malloc_node_t*)(data + data_size()); }
+};
+
+struct malloc_pool_t
+{
+	uint8_t* start;
+	size_t size;
+};
+
+static malloc_pool_t s_malloc_pools[s_malloc_pool_count];
+
+void init_malloc()
+{
+	size_t pool_size = s_malloc_pool_size_initial;
+	for (size_t i = 0; i < s_malloc_pool_count; i++)
+	{
+		s_malloc_pools[i].start = nullptr;
+		s_malloc_pools[i].size = pool_size;
+		pool_size *= s_malloc_pool_size_multiplier;
+	}
+}
+
+static bool allocate_pool(size_t pool_index)
+{
+	auto& pool = s_malloc_pools[pool_index];
+	assert(pool.start == nullptr);
+
+	// allocate memory for pool
+	pool.start = (uint8_t*)mmap(nullptr, pool.size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+	if (pool.start == nullptr)
+		return false;
+
+	// initialize pool to single unallocated node
+	auto* node = (malloc_node_t*)pool.start;
+	node->allocated = false;
+	node->size = pool.size;
+
+	return true;
+}
+
+static void* allocate_from_pool(size_t pool_index, size_t size)
+{
+	assert(size % s_malloc_default_align == 0);
+
+	auto& pool = s_malloc_pools[pool_index];
+	assert(pool.start != nullptr);
+
+	uint8_t* pool_end = pool.start + pool.size;
+
+	for (auto* node = (malloc_node_t*)pool.start; (uint8_t*)node < pool_end; node = node->next())
+	{
+		if (node->allocated)
+			continue;
+
+		{
+			// merge two unallocated nodes next to each other
+			auto* next = node->next();
+			if ((uint8_t*)next < pool_end && !next->allocated)
+				node->size += next->size;
+		}
+		
+		if (node->data_size() < size)
+			continue;
+
+		node->allocated = true;
+
+		// shrink node if needed
+		if (node->data_size() - size > sizeof(malloc_node_t))
+		{
+			uint8_t* node_end = (uint8_t*)node->next();
+
+			node->size = sizeof(malloc_node_t) + size;
+
+			auto* next = node->next();
+			next->allocated = false;
+			next->size = node_end - (uint8_t*)next;
+		}
+
+		return node->data;
+	}
+
+	return nullptr;
+}
+
+static malloc_node_t* node_from_data_pointer(void* data_pointer)
+{
+	return (malloc_node_t*)((uint8_t*)data_pointer - sizeof(malloc_node_t));
+}
+
+void* malloc(size_t size)
+{
+	// align size to s_malloc_default_align boundary
+	if (size_t ret = size % s_malloc_default_align)
+		size += s_malloc_default_align - ret;
+
+	// find the first pool with size atleast size
+	size_t first_usable_pool = 0;
+	while (s_malloc_pools[first_usable_pool].size < size)
+		first_usable_pool++;
+	// first_usable_pool = ceil(log(size/s_malloc_smallest_pool, s_malloc_pool_size_mult))
+
+	// try to find any already existing pools that we can allocate in
+	for (size_t i = first_usable_pool; i < s_malloc_pool_count; i++)
+		if (s_malloc_pools[i].start != nullptr)
+			if (void* ret = allocate_from_pool(i, size))
+				return ret;
+
+	// allocate new pool
+	for (size_t i = first_usable_pool; i < s_malloc_pool_count; i++)
+	{
+		if (s_malloc_pools[i].start != nullptr)
+			continue;
+		if (!allocate_pool(i))
+			break;
+		return allocate_from_pool(i, size);
+	}
+
+	errno = ENOMEM;
+	return nullptr;
+}
+
+void* realloc(void* ptr, size_t size)
+{
+	if (ptr == nullptr)
+		return malloc(size);
+	
+	// align size to s_malloc_default_align boundary
+	if (size_t ret = size % s_malloc_default_align)
+		size += s_malloc_default_align - ret;
+
+	auto* node = node_from_data_pointer(ptr);
+	size_t oldsize = node->data_size();
+
+	if (oldsize == size)
+		return ptr;
+
+	// shrink allocation if needed
+	if (oldsize > size)
+	{
+		if (node->data_size() - size > sizeof(malloc_node_t))
+		{
+			uint8_t* node_end = (uint8_t*)node->next();
+
+			node->size = sizeof(malloc_node_t) + size;
+
+			auto* next = node->next();
+			next->allocated = false;
+			next->size = node_end - (uint8_t*)next;
+		}
+		return ptr;
+	}
+
+	// FIXME: try to expand allocation
+
+	// allocate new pointer
+	void* new_ptr = malloc(size);
+	if (new_ptr == nullptr)
+		return nullptr;
+	
+	// move data to the new pointer
+	size_t bytes_to_copy = oldsize < size ? oldsize : size;
+	memcpy(new_ptr, ptr, bytes_to_copy);
+	free(ptr);
+
+	return new_ptr;
+}
+
+void free(void* ptr)
+{
+	if (ptr == nullptr)
+		return;
+
+	auto* node = node_from_data_pointer(ptr);
+
+	// mark node as unallocated and try to merge with the next node
+	node->allocated = false;
+	if (!node->next()->allocated)
+		node->size += node->next()->size;
+}
+
+void* calloc(size_t nmemb, size_t size)
+{
+	size_t total = nmemb * size;
+	if (size != 0 && total / size != nmemb)
+	{
+		errno = ENOMEM;
+		return nullptr;
+	}
+	void* ptr = malloc(total);
+	if (ptr == nullptr)
+		return nullptr;
+	memset(ptr, 0, total);
+	return ptr;
+}

libc/printf_impl.cpp

@@ -104,6 +104,7 @@ static void integer_to_string(char* buffer, T value, int base, bool upper, forma
 	buffer[offset++] = '\0';
 }
 
+#if __enable_sse
 template<BAN::floating_point T>
 static void floating_point_to_string(char* buffer, T value, bool upper, const format_options_t options)
 {
@@ -227,6 +228,7 @@ static void floating_point_to_exponent_string(char* buffer, T value, bool upper,
 	exponent_options.width = 3;
 	integer_to_string<int>(buffer + offset, exponent, 10, upper, exponent_options);
 }
+#endif
 
 extern "C" int printf_impl(const char* format, va_list arguments, int (*putc_fun)(int, void*), void* data)
 {
@@ -349,6 +351,7 @@ extern "C" int printf_impl(const char* format, va_list arguments, int (*putc_fun
 				format++;
 				break;
 			}
+#if __enable_sse
 			case 'e':
 			case 'E':
 			{
@@ -367,6 +370,7 @@ extern "C" int printf_impl(const char* format, va_list arguments, int (*putc_fun
 				format++;
 				break;
 			}
+#endif
 			case 'g':
 			case 'G':
 				// TODO

libc/stdlib.cpp

@@ -124,6 +124,16 @@ int putenv(char* string)
 		return -1;
 	}
 
+	if (!environ)
+	{
+		environ = (char**)malloc(sizeof(char*) * 2);
+		if (!environ)
+			return -1;
+		environ[0] = string;
+		environ[1] = nullptr;
+		return 0;
+	}
+
 	int cnt = 0;
 	for (int i = 0; string[i]; i++)
 		if (string[i] == '=')
@@ -151,10 +161,7 @@ int putenv(char* string)
 
 	char** new_envp = (char**)malloc(sizeof(char*) * (env_count + 2));
 	if (new_envp == nullptr)
-	{
-		errno = ENOMEM;
 		return -1;
-	}
 
 	for (int i = 0; i < env_count; i++)
 		new_envp[i] = environ[i];
@@ -164,47 +171,9 @@ int putenv(char* string)
 	free(environ);
 	environ = new_envp;
 
-	if (syscall(SYS_SETENVP, environ) == -1)
-		return -1;
 	return 0;
 }
 
-void* malloc(size_t bytes)
-{
-	long res = syscall(SYS_ALLOC, bytes);
-	if (res < 0)
-		return nullptr;
-	return (void*)res;
-}
-
-void* calloc(size_t nmemb, size_t size)
-{
-	if (nmemb * size < nmemb)
-		return nullptr;
-	void* ptr = malloc(nmemb * size);
-	if (ptr == nullptr)
-		return nullptr;
-	memset(ptr, 0, nmemb * size);
-	return ptr;
-}
-
-void* realloc(void* ptr, size_t size)
-{
-	if (ptr == nullptr)
-		return malloc(size);
-	long ret = syscall(SYS_REALLOC, ptr, size);
-	if (ret == -1)
-		return nullptr;
-	return (void*)ret;
-}
-
-void free(void* ptr)
-{
-	if (ptr == nullptr)
-		return;
-	syscall(SYS_FREE, ptr);
-}
-
 // Constants and algorithm from https://en.wikipedia.org/wiki/Permuted_congruential_generator
 
 static uint64_t s_rand_state = 0x4d595df4d0f33173;

libc/sys/mman.cpp

@@ -0,0 +1,23 @@
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+void* mmap(void* addr, size_t len, int prot, int flags, int fildes, off_t off)
+{
+	sys_mmap_t args {
+		.addr = addr,
+		.len = len,
+		.prot = prot,
+		.flags = flags,
+		.off = off
+	};
+	long ret = syscall(SYS_MMAP, &args);
+	if (ret == -1)
+		return nullptr;
+	return (void*)ret;
+}
+
+int munmap(void* addr, size_t len)
+{
+	return syscall(SYS_MUNMAP, addr, len);
+}

libc/unistd.cpp

@@ -11,9 +11,26 @@
 
 char** environ;
 
+extern void init_malloc();
 extern "C" void _init_libc(char** _environ)
 {
-	environ = _environ;
+	init_malloc();
+
+	if (!_environ)
+		return;
+
+	size_t env_count = 0;
+	while (_environ[env_count])
+		env_count++;
+	
+	environ = (char**)malloc(sizeof(char*) * env_count + 1);
+	for (size_t i = 0; i < env_count; i++)
+	{
+		size_t bytes = strlen(_environ[i]) + 1;
+		environ[i] = (char*)malloc(bytes);
+		memcpy(environ[i], _environ[i], bytes);
+	}
+	environ[env_count] = nullptr;
 }
 
 void _exit(int status)

linecount.sh

@@ -1,3 +0,0 @@
-#!/bin/bash
-
-find . | grep -vE '(build|toolchain)' | grep -E '\.(cpp|h|S)$' | xargs wc -l | sort -n

qemu.sh

@@ -6,4 +6,4 @@ qemu-system-$BANAN_ARCH										\
 	-smp 2													\
 	-drive format=raw,media=disk,file=${DISK_IMAGE_PATH}	\
 	-serial stdio											\
-	-accel kvm												\
+	$@														\

userspace/Shell/main.cpp

@@ -437,6 +437,40 @@ pid_t execute_command_no_wait(BAN::Vector<BAN::String>& args, int fd_in, int fd_
 		MUST(cmd_args.push_back((char*)arg.data()));
 	MUST(cmd_args.push_back(nullptr));
 
+	// do PATH resolution
+	BAN::String executable_file;
+	if (!args.front().empty() && args.front().front() != '.' && args.front().front() != '/')
+	{
+		char* path_env_cstr = getenv("PATH");
+		if (path_env_cstr)
+		{
+			auto path_env_list = MUST(BAN::StringView(path_env_cstr).split(':'));
+			for (auto path_env : path_env_list)
+			{
+				BAN::String test_file = path_env;
+				MUST(test_file.push_back('/'));
+				MUST(test_file.append(args.front()));
+
+				struct stat st;
+				if (stat(test_file.data(), &st) == 0)
+				{
+					executable_file = BAN::move(test_file);
+					break;
+				}
+			}
+
+			if (executable_file.empty())
+			{
+				fprintf(stderr, "command not found: %s\n", args.front().data());
+				return -1;
+			}
+		}
+	}
+	else
+	{
+		executable_file = args.front();
+	}
+
 	pid_t pid = fork();
 	if (pid == 0)
 	{
@@ -477,11 +511,14 @@ pid_t execute_command_no_wait(BAN::Vector<BAN::String>& args, int fd_in, int fd_
 			setpgid(0, pgrp);
 		}
 
-		execv(cmd_args.front(), cmd_args.data());
+		execv(executable_file.data(), cmd_args.data());
 		perror("execv");
 		exit(1);
 	}
 
+	if (pid == -1)
+		ERROR_RETURN("fork", -1);
+
 	return pid;
 }
 
@@ -489,7 +526,7 @@ int execute_command(BAN::Vector<BAN::String>& args, int fd_in, int fd_out)
 {
 	pid_t pid = execute_command_no_wait(args, fd_in, fd_out, 0);
 	if (pid == -1)
-		ERROR_RETURN("fork", 1);
+		return 1;
 
 	int status;
 	if (waitpid(pid, &status, 0) == -1)

userspace/init/main.cpp

@@ -74,6 +74,8 @@ int main()
 			if (setuid(pwd->pw_uid) == -1)
 				perror("setuid");
 
+			setenv("PATH", "/bin:/usr/bin", 0);
+
 			setenv("HOME", pwd->pw_dir, 1);
 			chdir(pwd->pw_dir);