Kernel: Fix all broken locks from new mutexes

LibELF/LibELF/ELF.cpp

@@ -4,7 +4,6 @@
 
 #ifdef __is_kernel
 #include <kernel/FS/VirtualFileSystem.h>
-#include <kernel/Memory/PageTableScope.h>
 #include <kernel/Process.h>
 #endif
 

LibELF/LibELF/LoadableELF.cpp

@@ -1,7 +1,7 @@
 #include <BAN/ScopeGuard.h>
 #include <kernel/CriticalScope.h>
 #include <kernel/Memory/Heap.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <LibELF/LoadableELF.h>
 #include <LibELF/Values.h>
 
@@ -282,10 +282,6 @@ namespace LibELF
 
 		elf->reserve_address_space();
 
-		ASSERT(&PageTable::current() == &m_page_table);
-		LockGuard _(m_page_table);
-		ASSERT(m_page_table.is_page_free(0));
-
 		for (const auto& program_header : m_program_headers)
 		{
 			switch (program_header.p_type)
@@ -315,12 +311,9 @@ namespace LibELF
 						if (paddr == 0)
 							return BAN::Error::from_errno(ENOMEM);
 
-						{
+						PageTable::with_fast_page(paddr, [&] {
-							CriticalScope _;
-							PageTable::map_fast_page(paddr);
 							memcpy(PageTable::fast_page_as_ptr(), (void*)(start + i * PAGE_SIZE), PAGE_SIZE);
-							PageTable::unmap_fast_page();
+						});
-						}
 
 						new_page_table.map_page_at(paddr, start + i * PAGE_SIZE, flags);
 						elf->m_physical_page_count++;

kernel/CMakeLists.txt

@@ -42,6 +42,7 @@ set(KERNEL_SOURCES
 	kernel/Input/PS2/Mouse.cpp
 	kernel/InterruptController.cpp
 	kernel/kernel.cpp
+	kernel/Lock/SpinLock.cpp
 	kernel/Memory/DMARegion.cpp
 	kernel/Memory/FileBackedRegion.cpp
 	kernel/Memory/Heap.cpp
@@ -68,7 +69,6 @@ set(KERNEL_SOURCES
 	kernel/Random.cpp
 	kernel/Scheduler.cpp
 	kernel/Semaphore.cpp
-	kernel/SpinLock.cpp
 	kernel/SSP.cpp
 	kernel/Storage/ATA/AHCI/Controller.cpp
 	kernel/Storage/ATA/AHCI/Device.cpp

kernel/arch/x86_64/PageTable.cpp

@@ -1,7 +1,7 @@
 #include <kernel/Arch.h>
 #include <kernel/CPUID.h>
 #include <kernel/InterruptController.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/SpinLock.h>
 #include <kernel/Memory/kmalloc.h>
 #include <kernel/Memory/PageTable.h>
 
@@ -17,6 +17,8 @@ extern uint8_t g_userspace_end[];
 namespace Kernel
 {
 
+	SpinLock PageTable::s_fast_page_lock;
+
 	static PageTable* s_kernel = nullptr;
 	static PageTable* s_current = nullptr;
 	static bool s_has_nxe = false;
@@ -250,7 +252,7 @@ namespace Kernel
 
 	BAN::ErrorOr<PageTable*> PageTable::create_userspace()
 	{
-		LockGuard _(s_kernel->m_lock);
+		SpinLockGuard _(s_kernel->m_lock);
 		PageTable* page_table = new PageTable;
 		if (page_table == nullptr)
 			return BAN::Error::from_errno(ENOMEM);
@@ -331,7 +333,7 @@ namespace Kernel
 		uint64_t pde   = (uc_vaddr >> 21) & 0x1FF;
 		uint64_t pte   = (uc_vaddr >> 12) & 0x1FF;
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 
 		if (is_page_free(vaddr))
 		{
@@ -353,7 +355,7 @@ namespace Kernel
 		vaddr_t s_page = vaddr / PAGE_SIZE;
 		vaddr_t e_page = BAN::Math::div_round_up<vaddr_t>(vaddr + size, PAGE_SIZE);
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		for (vaddr_t page = s_page; page < e_page; page++)
 			unmap_page(page * PAGE_SIZE);
 	}
@@ -392,7 +394,7 @@ namespace Kernel
 		// NOTE: we add present here, since it has to be available in higher level structures
 		flags_t uwr_flags = (flags & (Flags::UserSupervisor | Flags::ReadWrite)) | Flags::Present;
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 
 		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
 		if ((pml4[pml4e] & uwr_flags) != uwr_flags)
@@ -437,7 +439,7 @@ namespace Kernel
 
 		size_t page_count = range_page_count(vaddr, size);
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		for (size_t page = 0; page < page_count; page++)
 			map_page_at(paddr + page * PAGE_SIZE, vaddr + page * PAGE_SIZE, flags);
 	}
@@ -454,7 +456,7 @@ namespace Kernel
 		uint64_t pde   = (uc_vaddr >> 21) & 0x1FF;
 		uint64_t pte   = (uc_vaddr >> 12) & 0x1FF;
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 
 		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
 		if (!(pml4[pml4e] & Flags::Present))
@@ -488,7 +490,7 @@ namespace Kernel
 
 	bool PageTable::reserve_page(vaddr_t vaddr, bool only_free)
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		ASSERT(vaddr % PAGE_SIZE == 0);
 		if (only_free && !is_page_free(vaddr))
 			return false;
@@ -502,7 +504,7 @@ namespace Kernel
 			bytes += PAGE_SIZE - rem;
 		ASSERT(vaddr % PAGE_SIZE == 0);
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		if (only_free && !is_range_free(vaddr, bytes))
 			return false;
 		for (size_t offset = 0; offset < bytes; offset += PAGE_SIZE)
@@ -534,7 +536,7 @@ namespace Kernel
 		const uint16_t e_pde   = (uc_vaddr_end >> 21) & 0x1FF;
 		const uint16_t e_pte   = (uc_vaddr_end >> 12) & 0x1FF;
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 
 		// Try to find free page that can be mapped without
 		// allocations (page table with unused entries)
@@ -607,7 +609,7 @@ namespace Kernel
 		ASSERT(is_canonical(first_address));
 		ASSERT(is_canonical(last_address));
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 
 		for (vaddr_t vaddr = first_address; vaddr < last_address;)
 		{
@@ -648,7 +650,7 @@ namespace Kernel
 		vaddr_t s_page = vaddr / PAGE_SIZE;
 		vaddr_t e_page = BAN::Math::div_round_up<vaddr_t>(vaddr + size, PAGE_SIZE);
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		for (vaddr_t page = s_page; page < e_page; page++)
 			if (!is_page_free(page * PAGE_SIZE))
 				return false;
@@ -671,7 +673,7 @@ namespace Kernel
 
 	void PageTable::debug_dump()
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 
 		flags_t flags = 0;
 		vaddr_t start = 0;

kernel/icxxabi.cpp

@@ -1,6 +1,5 @@
-#include <kernel/LockGuard.h>
+#include <BAN/Atomic.h>
 #include <kernel/Panic.h>
-#include <kernel/SpinLock.h>
 
 #define ATEXIT_MAX_FUNCS 128
 
@@ -115,22 +114,18 @@ void __cxa_finalize(void *f)
 
 namespace __cxxabiv1
 {
-	/* guard variables */
+	using __guard = uint64_t;
-	static Kernel::SpinLock s_spin_lock;
-
-	/* The ABI requires a 64-bit type.  */
-	__extension__ typedef int __guard __attribute__((mode(__DI__)));
 
 	int __cxa_guard_acquire (__guard* g)
 	{
-		Kernel::LockGuard lock_guard(s_spin_lock);
+		auto& atomic = *reinterpret_cast<BAN::Atomic<__guard>*>(g);
-		return !*(int*)g;
+		return atomic == 0;
 	}
 
 	void __cxa_guard_release (__guard* g)
 	{
-		Kernel::LockGuard lock_guard(s_spin_lock);
+		auto& atomic = *reinterpret_cast<BAN::Atomic<__guard>*>(g);
-		*(int*)g = 1;
+		atomic = 1;
 	}
 
 	void __cxa_guard_abort (__guard*)

kernel/include/kernel/Debug.h

@@ -1,32 +1,30 @@
 #pragma once
 
 #include <BAN/Formatter.h>
+#include <kernel/Lock/SpinLock.h>
 
 #define dprintln(...)										\
 	do {													\
-		Debug::DebugLock::lock();							\
+		Kernel::SpinLockGuard _(Debug::s_debug_lock);		\
 		Debug::print_prefix(__FILE__, __LINE__);			\
 		BAN::Formatter::print(Debug::putchar, __VA_ARGS__);	\
 		BAN::Formatter::print(Debug::putchar, "\r\n");		\
-		Debug::DebugLock::unlock();							\
 	} while(false)
 
 #define dwarnln(...)										\
 	do {													\
-		Debug::DebugLock::lock();							\
+		Kernel::SpinLockGuard _(Debug::s_debug_lock);		\
 		BAN::Formatter::print(Debug::putchar, "\e[33m");	\
 		dprintln(__VA_ARGS__);								\
 		BAN::Formatter::print(Debug::putchar, "\e[m");		\
-		Debug::DebugLock::unlock();							\
 	} while(false)
 
 #define derrorln(...)										\
 	do {													\
-		Debug::DebugLock::lock();							\
+		Kernel::SpinLockGuard _(Debug::s_debug_lock);		\
 		BAN::Formatter::print(Debug::putchar, "\e[31m");	\
 		dprintln(__VA_ARGS__);								\
 		BAN::Formatter::print(Debug::putchar, "\e[m");		\
-		Debug::DebugLock::unlock();							\
 	} while(false)
 
 #define dprintln_if(cond, ...)		\
@@ -55,10 +53,5 @@ namespace Debug
 	void putchar(char);
 	void print_prefix(const char*, int);
 
-	class DebugLock
+	extern Kernel::RecursiveSpinLock s_debug_lock;
-	{
-	public:
-		static void lock();
-		static void unlock();
-	};
 }

kernel/include/kernel/FS/DevFS/FileSystem.h

@@ -3,6 +3,7 @@
 #include <BAN/Vector.h>
 #include <kernel/Device/Device.h>
 #include <kernel/FS/TmpFS/FileSystem.h>
+#include <kernel/Lock/Mutex.h>
 #include <kernel/Semaphore.h>
 
 namespace Kernel
@@ -29,7 +30,7 @@ namespace Kernel
 		{ }
 
 	private:
-		mutable SpinLock m_device_lock;
+		mutable Mutex m_device_lock;
 
 		BAN::Vector<BAN::RefPtr<Device>> m_devices;
 

kernel/include/kernel/FS/Ext2/FileSystem.h

@@ -106,7 +106,7 @@ namespace Kernel
 		};
 
 	private:
-		RecursiveSpinLock m_lock;
+		Mutex m_mutex;
 
 		BAN::RefPtr<BlockDevice> m_block_device;
 

kernel/include/kernel/FS/Inode.h

@@ -9,7 +9,8 @@
 
 #include <kernel/API/DirectoryEntry.h>
 #include <kernel/Credentials.h>
-#include <kernel/SpinLock.h>
+#include <kernel/Debug.h>
+#include <kernel/Lock/Mutex.h>
 
 #include <sys/socket.h>
 #include <sys/types.h>
@@ -157,7 +158,7 @@ namespace Kernel
 		virtual BAN::ErrorOr<long> ioctl_impl(int request, void* arg)		{ return BAN::Error::from_errno(ENOTSUP); }
 
 	protected:
-		mutable RecursivePrioritySpinLock m_lock;
+		mutable PriorityMutex m_mutex;
 
 	private:
 		BAN::WeakPtr<SharedFileData> m_shared_region;

kernel/include/kernel/FS/Pipe.h

@@ -2,7 +2,6 @@
 
 #include <kernel/FS/Inode.h>
 #include <kernel/Semaphore.h>
-#include <kernel/SpinLock.h>
 
 namespace Kernel
 {

kernel/include/kernel/FS/TmpFS/FileSystem.h

@@ -4,9 +4,8 @@
 #include <BAN/Iteration.h>
 #include <kernel/FS/FileSystem.h>
 #include <kernel/FS/TmpFS/Inode.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Memory/PageTable.h>
-#include <kernel/SpinLock.h>
 
 namespace Kernel
 {
@@ -119,7 +118,7 @@ namespace Kernel
 	private:
 		const dev_t m_rdev;
 
-		RecursiveSpinLock m_lock;
+		Mutex m_mutex;
 
 		BAN::HashMap<ino_t, BAN::RefPtr<TmpInode>> m_inode_cache;
 		BAN::RefPtr<TmpDirectoryInode> m_root_inode;
@@ -155,7 +154,7 @@ namespace Kernel
 	template<TmpFuncs::with_block_buffer_callback F>
 	void TmpFileSystem::with_block_buffer(size_t index, F callback)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		paddr_t block_paddr = find_block(index);
 		PageTable::with_fast_page(block_paddr, [&] {
 			BAN::ByteSpan buffer(reinterpret_cast<uint8_t*>(PageTable::fast_page()), PAGE_SIZE);
@@ -166,7 +165,7 @@ namespace Kernel
 	template<TmpFuncs::for_each_inode_callback F>
 	void TmpFileSystem::for_each_inode(F callback)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		for (auto& [_, inode] : m_inode_cache)
 		{
 			switch (callback(inode))

kernel/include/kernel/FS/VirtualFileSystem.h

@@ -3,7 +3,7 @@
 #include <BAN/String.h>
 #include <BAN/Vector.h>
 #include <kernel/FS/FileSystem.h>
-#include <kernel/SpinLock.h>
+#include <kernel/Lock/Mutex.h>
 
 namespace Kernel
 {
@@ -42,7 +42,7 @@ namespace Kernel
 		MountPoint* mount_from_root_inode(BAN::RefPtr<Inode>);
 
 	private:
-		SpinLock				m_lock;
+		Mutex					m_mutex;
 		FileSystem*				m_root_fs = nullptr;
 		BAN::Vector<MountPoint>	m_mount_points;
 	};

kernel/include/kernel/Input/PS2/Controller.h

@@ -5,7 +5,7 @@
 #include <kernel/Device/Device.h>
 #include <kernel/Input/PS2/Config.h>
 #include <kernel/InterruptController.h>
-#include <kernel/SpinLock.h>
+#include <kernel/Lock/Mutex.h>
 
 namespace Kernel::Input
 {
@@ -60,7 +60,7 @@ namespace Kernel::Input
 
 	private:
 		BAN::RefPtr<PS2Device> m_devices[2];
-		RecursiveSpinLock m_lock;
+		Mutex m_mutex;
 
 		BAN::CircularQueue<Command, 128> m_command_queue;
 		uint64_t m_command_send_time { 0 };

kernel/include/kernel/InterruptController.h

@@ -51,6 +51,11 @@ namespace Kernel
 		bool m_using_apic { false };
 	};
 
-	bool interrupts_enabled();
+	inline bool interrupts_enabled()
+	{
+		uintptr_t flags;
+		asm volatile("pushf; pop %0" : "=r"(flags) :: "memory");
+		return flags & (1 << 9);
+	}
 
 }

kernel/include/kernel/Lock/Mutex.h

@@ -0,0 +1,131 @@
+#pragma once
+
+#include <BAN/Atomic.h>
+#include <BAN/NoCopyMove.h>
+#include <kernel/Scheduler.h>
+
+#include <sys/types.h>
+
+namespace Kernel
+{
+
+	class Mutex
+	{
+		BAN_NON_COPYABLE(Mutex);
+		BAN_NON_MOVABLE(Mutex);
+
+	public:
+		Mutex() = default;
+
+		void lock()
+		{
+			auto tid = Scheduler::current_tid();
+			if (tid == m_locker)
+				ASSERT_GT(m_lock_depth, 0);
+			else
+			{
+				while (!m_locker.compare_exchange(-1, tid))
+					Scheduler::get().reschedule();
+				ASSERT_EQ(m_lock_depth, 0);
+			}
+			m_lock_depth++;
+		}
+
+		bool try_lock()
+		{
+			auto tid = Scheduler::current_tid();
+			if (tid == m_locker)
+				ASSERT_GT(m_lock_depth, 0);
+			else
+			{
+				if (!m_locker.compare_exchange(-1, tid))
+					return false;
+				ASSERT_EQ(m_lock_depth, 0);
+			}
+			m_lock_depth++;
+		}
+
+		void unlock()
+		{
+			ASSERT_EQ(m_locker.load(), Scheduler::current_tid());
+			ASSERT_GT(m_lock_depth, 0);
+			if (--m_lock_depth == 0)
+				m_locker = -1;
+		}
+
+		pid_t locker() const { return m_locker; }
+		bool is_locked() const { return m_locker != -1; }
+		uint32_t lock_depth() const { return m_lock_depth; }
+
+	private:
+		BAN::Atomic<pid_t>	m_locker		{ -1 };
+		uint32_t			m_lock_depth	{  0 };
+	};
+
+	class PriorityMutex
+	{
+		BAN_NON_COPYABLE(PriorityMutex);
+		BAN_NON_MOVABLE(PriorityMutex);
+
+	public:
+		PriorityMutex() = default;
+
+		void lock()
+		{
+			auto tid = Scheduler::current_tid();
+			if (tid == m_locker)
+				ASSERT_GT(m_lock_depth, 0);
+			else
+			{
+				bool has_priority = tid ? !Thread::current().is_userspace() : true;
+				if (has_priority)
+					m_queue_length++;
+				while (!(has_priority || m_queue_length == 0) || !m_locker.compare_exchange(-1, tid))
+					Scheduler::get().reschedule();
+				ASSERT_EQ(m_lock_depth, 0);
+			}
+			m_lock_depth++;
+		}
+
+		bool try_lock()
+		{
+			auto tid = Scheduler::current_tid();
+			if (tid == m_locker)
+				ASSERT_GT(m_lock_depth, 0);
+			else
+			{
+				bool has_priority = tid ? !Thread::current().is_userspace() : true;
+				if (!(has_priority || m_queue_length == 0) || !m_locker.compare_exchange(-1, tid))
+					return false;
+				if (has_priority)
+					m_queue_length++;
+				ASSERT_EQ(m_lock_depth, 0);
+			}
+			m_lock_depth++;
+		}
+
+		void unlock()
+		{
+			auto tid = Scheduler::current_tid();
+			ASSERT_EQ(m_locker.load(), tid);
+			ASSERT_GT(m_lock_depth, 0);
+			if (--m_lock_depth == 0)
+			{
+				bool has_priority = tid ? !Thread::current().is_userspace() : true;
+				if (has_priority)
+					m_queue_length--;
+				m_locker = -1;
+			}
+		}
+
+		pid_t locker() const { return m_locker; }
+		bool is_locked() const { return m_locker != -1; }
+		uint32_t lock_depth() const { return m_lock_depth; }
+
+	private:
+		BAN::Atomic<pid_t>		m_locker		{ -1 };
+		uint32_t				m_lock_depth	{  0 };
+		BAN::Atomic<uint32_t>	m_queue_length	{  0 };
+	};
+
+}

kernel/include/kernel/Lock/SpinLock.h

@@ -0,0 +1,67 @@
+#pragma once
+
+#include <BAN/Atomic.h>
+#include <BAN/NoCopyMove.h>
+
+#include <sys/types.h>
+
+namespace Kernel
+{
+
+	using InterruptState = bool;
+
+	class SpinLock
+	{
+		BAN_NON_COPYABLE(SpinLock);
+		BAN_NON_MOVABLE(SpinLock);
+
+	public:
+		SpinLock() = default;
+
+		InterruptState lock();
+		void unlock(InterruptState state);
+
+	private:
+		BAN::Atomic<pid_t> m_locker { -1 };
+	};
+
+	class RecursiveSpinLock
+	{
+		BAN_NON_COPYABLE(RecursiveSpinLock);
+		BAN_NON_MOVABLE(RecursiveSpinLock);
+
+	public:
+		RecursiveSpinLock() = default;
+
+		InterruptState lock();
+		void unlock(InterruptState state);
+
+	private:
+		BAN::Atomic<pid_t> m_locker { -1 };
+		uint32_t m_lock_depth { 0 };
+	};
+
+	template<typename Lock>
+	class SpinLockGuard
+	{
+		BAN_NON_COPYABLE(SpinLockGuard);
+		BAN_NON_MOVABLE(SpinLockGuard);
+
+	public:
+		SpinLockGuard(Lock& lock)
+			: m_lock(lock)
+		{
+			m_state = m_lock.lock();
+		}
+
+		~SpinLockGuard()
+		{
+			m_lock.unlock(m_state);
+		}
+
+	private:
+		Lock& m_lock;
+		InterruptState m_state;
+	};
+
+}

kernel/include/kernel/Memory/Heap.h

@@ -3,8 +3,8 @@
 #include <BAN/NoCopyMove.h>
 #include <BAN/Vector.h>
 
+#include <kernel/Lock/SpinLock.h>
 #include <kernel/Memory/PhysicalRange.h>
-#include <kernel/SpinLock.h>
 
 namespace Kernel
 {

kernel/include/kernel/Memory/PageTable.h

@@ -3,8 +3,8 @@
 #include <BAN/Errors.h>
 #include <BAN/Traits.h>
 #include <kernel/CriticalScope.h>
+#include <kernel/Lock/SpinLock.h>
 #include <kernel/Memory/Types.h>
-#include <kernel/SpinLock.h>
 
 namespace Kernel
 {
@@ -15,6 +15,12 @@ namespace Kernel
 		requires BAN::is_same_v<decltype(func()), void>;
 	};
 
+	template<typename F>
+	concept with_fast_page_callback_error = requires(F func)
+	{
+		requires BAN::is_same_v<decltype(func()), BAN::ErrorOr<void>>;
+	};
+
 	class PageTable
 	{
 	public:
@@ -37,19 +43,27 @@ namespace Kernel
 		static PageTable& kernel();
 		static PageTable& current();
 
-		static void map_fast_page(paddr_t);
-		static void unmap_fast_page();
 		static constexpr vaddr_t fast_page() { return KERNEL_OFFSET; }
 
 		template<with_fast_page_callback F>
 		static void with_fast_page(paddr_t paddr, F callback)
 		{
-			CriticalScope _;
+			SpinLockGuard _(s_fast_page_lock);
 			map_fast_page(paddr);
 			callback();
 			unmap_fast_page();
 		}
 
+		template<with_fast_page_callback_error F>
+		static BAN::ErrorOr<void> with_fast_page(paddr_t paddr, F callback)
+		{
+			SpinLockGuard _(s_fast_page_lock);
+			map_fast_page(paddr);
+			auto ret = callback();
+			unmap_fast_page();
+			return ret;
+		}
+
 		// FIXME: implement sized checks, return span, etc
 		static void* fast_page_as_ptr(size_t offset = 0)
 		{
@@ -97,8 +111,8 @@ namespace Kernel
 
 		void load();
 
-		void lock() const { m_lock.lock(); }
+		InterruptState lock() const { return m_lock.lock(); }
-		void unlock() const { m_lock.unlock(); }
+		void unlock(InterruptState state) const { m_lock.unlock(state); }
 
 		void debug_dump();
 
@@ -110,9 +124,13 @@ namespace Kernel
 		void prepare_fast_page();
 		static void invalidate(vaddr_t);
 
+		static void map_fast_page(paddr_t);
+		static void unmap_fast_page();
+
 	private:
 		paddr_t						m_highest_paging_struct { 0 };
 		mutable RecursiveSpinLock	m_lock;
+		static SpinLock				s_fast_page_lock;
 	};
 
 	static constexpr size_t range_page_count(vaddr_t start, size_t bytes)

kernel/include/kernel/Memory/PageTableScope.h

@@ -1,33 +0,0 @@
-#pragma once
-
-#include <kernel/CriticalScope.h>
-#include <kernel/LockGuard.h>
-#include <kernel/Memory/PageTable.h>
-
-namespace Kernel
-{
-
-	class PageTableScope
-	{
-	public:
-		PageTableScope(PageTable& page_table)
-			: m_guard(page_table)
-			, m_old(PageTable::current())
-			, m_temp(page_table)
-		{
-			if (&m_old != &m_temp)
-				m_temp.load();
-		}
-		~PageTableScope()
-		{
-			if (&m_old != &m_temp)
-				m_old.load();
-		}
-	private:
-		LockGuard<PageTable> m_guard;
-		CriticalScope m_scope;
-		PageTable& m_old;
-		PageTable& m_temp;
-	};
-
-}

kernel/include/kernel/Networking/ARPTable.h

@@ -51,7 +51,7 @@ namespace Kernel
 		};
 
 	private:
-		SpinLock m_lock;
+		SpinLock m_table_lock;
 
 		BAN::HashMap<BAN::IPv4Address, BAN::MACAddress> m_arp_table;
 

kernel/include/kernel/Networking/IPv4Layer.h

@@ -12,7 +12,6 @@
 #include <kernel/Networking/NetworkLayer.h>
 #include <kernel/Networking/NetworkSocket.h>
 #include <kernel/Process.h>
-#include <kernel/SpinLock.h>
 
 namespace Kernel
 {
@@ -68,7 +67,7 @@ namespace Kernel
 		};
 
 	private:
-		RecursiveSpinLock		m_lock;
+		RecursiveSpinLock		m_bound_socket_lock;
 
 		BAN::UniqPtr<ARPTable>	m_arp_table;
 		Process*				m_process { nullptr };

kernel/include/kernel/Networking/TCPSocket.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <BAN/Endianness.h>
+#include <kernel/Lock/Mutex.h>
 #include <kernel/Memory/VirtualRange.h>
 #include <kernel/Networking/NetworkInterface.h>
 #include <kernel/Networking/NetworkSocket.h>
@@ -119,7 +120,7 @@ namespace Kernel
 
 		uint64_t m_time_wait_start_ms { 0 };
 
-		RecursiveSpinLock	m_lock;
+		Mutex		m_lock;
 		Semaphore	m_semaphore;
 
 		BAN::Atomic<bool> m_should_ack { false };

kernel/include/kernel/Networking/UDPSocket.h

@@ -2,6 +2,7 @@
 
 #include <BAN/CircularQueue.h>
 #include <BAN/Endianness.h>
+#include <kernel/Lock/SpinLock.h>
 #include <kernel/Memory/VirtualRange.h>
 #include <kernel/Networking/NetworkInterface.h>
 #include <kernel/Networking/NetworkSocket.h>

kernel/include/kernel/Networking/UNIX/Socket.h

@@ -4,6 +4,7 @@
 #include <BAN/WeakPtr.h>
 #include <kernel/FS/Socket.h>
 #include <kernel/FS/TmpFS/Inode.h>
+#include <kernel/Lock/SpinLock.h>
 
 namespace Kernel
 {
@@ -65,6 +66,7 @@ namespace Kernel
 		BAN::CircularQueue<size_t, 128>	m_packet_sizes;
 		size_t							m_packet_size_total { 0 };
 		BAN::UniqPtr<VirtualRange>		m_packet_buffer;
+		SpinLock						m_packet_lock;
 		Semaphore						m_packet_semaphore;
 
 		friend class BAN::RefPtr<UnixDomainSocket>;

kernel/include/kernel/Process.h

@@ -7,10 +7,10 @@
 #include <BAN/Vector.h>
 #include <kernel/Credentials.h>
 #include <kernel/FS/Inode.h>
+#include <kernel/Lock/Mutex.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/MemoryRegion.h>
 #include <kernel/OpenFileDescriptorSet.h>
-#include <kernel/SpinLock.h>
 #include <kernel/Terminal/TTY.h>
 #include <kernel/Thread.h>
 
@@ -51,9 +51,6 @@ namespace Kernel
 		void register_to_scheduler();
 		void exit(int status, int signal);
 
-		static void for_each_process(const BAN::Function<BAN::Iteration(Process&)>& callback);
-		static void for_each_process_in_session(pid_t sid, const BAN::Function<BAN::Iteration(Process&)>& callback);
-
 		void add_thread(Thread*);
 		void on_thread_exit(Thread&);
 
@@ -222,7 +219,7 @@ namespace Kernel
 		const pid_t m_pid;
 		const pid_t m_parent;
 
-		mutable RecursiveSpinLock m_lock;
+		mutable Mutex m_process_lock;
 
 		BAN::String m_working_directory;
 		BAN::Vector<Thread*> m_threads;

kernel/include/kernel/SpinLock.h

@@ -1,65 +0,0 @@
-#pragma once
-
-#include <BAN/Atomic.h>
-#include <BAN/NoCopyMove.h>
-
-#include <sys/types.h>
-
-namespace Kernel
-{
-
-	class SpinLock
-	{
-		BAN_NON_COPYABLE(SpinLock);
-		BAN_NON_MOVABLE(SpinLock);
-
-	public:
-		SpinLock() = default;
-		void lock();
-		void unlock();
-		bool is_locked() const;
-
-		uint32_t lock_depth() const { return m_locker != -1; }
-
-	private:
-		BAN::Atomic<pid_t> m_locker = -1;
-	};
-
-	class RecursiveSpinLock
-	{
-		BAN_NON_COPYABLE(RecursiveSpinLock);
-		BAN_NON_MOVABLE(RecursiveSpinLock);
-
-	public:
-		RecursiveSpinLock() = default;
-		void lock();
-		void unlock();
-		bool is_locked() const;
-
-		uint32_t lock_depth() const { return m_lock_depth; }
-
-	private:
-		BAN::Atomic<pid_t>		m_locker		= -1;
-		BAN::Atomic<uint32_t>	m_lock_depth	= 0;
-	};
-
-	class RecursivePrioritySpinLock
-	{
-		BAN_NON_COPYABLE(RecursivePrioritySpinLock);
-		BAN_NON_MOVABLE(RecursivePrioritySpinLock);
-
-	public:
-		RecursivePrioritySpinLock() = default;
-		void lock();
-		void unlock();
-		bool is_locked() const;
-
-		uint32_t lock_depth() const { return m_lock_depth; }
-
-	private:
-		BAN::Atomic<pid_t>		m_locker		= -1;
-		BAN::Atomic<uint32_t>	m_lock_depth	= 0;
-		BAN::Atomic<uint32_t>	m_queue_length	= 0;
-	};
-
-}

kernel/include/kernel/Storage/ATA/ATABus.h

@@ -4,7 +4,7 @@
 #include <BAN/RefPtr.h>
 #include <BAN/Vector.h>
 #include <kernel/InterruptController.h>
-#include <kernel/SpinLock.h>
+#include <kernel/Lock/Mutex.h>
 
 namespace Kernel
 {
@@ -51,7 +51,7 @@ namespace Kernel
 	private:
 		const uint16_t m_base;
 		const uint16_t m_ctrl;
-		SpinLock m_lock;
+		Mutex m_mutex;
 
 		volatile bool m_has_got_irq { false };
 

kernel/include/kernel/Storage/DiskCache.h

@@ -3,7 +3,6 @@
 #include <BAN/Array.h>
 #include <BAN/ByteSpan.h>
 #include <kernel/Memory/Types.h>
-#include <kernel/SpinLock.h>
 
 namespace Kernel
 {

kernel/include/kernel/Storage/NVMe/Queue.h

@@ -3,6 +3,7 @@
 #include <BAN/UniqPtr.h>
 #include <BAN/Vector.h>
 #include <kernel/InterruptController.h>
+#include <kernel/Lock/Mutex.h>
 #include <kernel/Memory/DMARegion.h>
 #include <kernel/Semaphore.h>
 #include <kernel/Storage/NVMe/Definitions.h>
@@ -20,7 +21,7 @@ namespace Kernel
 		virtual void handle_irq() final override;
 
 	private:
-		SpinLock m_lock;
+		Mutex m_mutex;
 		BAN::UniqPtr<Kernel::DMARegion> m_completion_queue;
 		BAN::UniqPtr<Kernel::DMARegion> m_submission_queue;
 		volatile NVMe::DoorbellRegisters& m_doorbell;

kernel/include/kernel/Storage/StorageDevice.h

@@ -2,6 +2,7 @@
 
 #include <BAN/Vector.h>
 #include <kernel/Device/Device.h>
+#include <kernel/Lock/Mutex.h>
 #include <kernel/Storage/DiskCache.h>
 #include <kernel/Storage/Partition.h>
 
@@ -44,7 +45,7 @@ namespace Kernel
 		virtual bool has_error_impl() const override { return false; }
 
 	private:
-		SpinLock							m_lock;
+		Mutex								m_mutex;
 		BAN::Optional<DiskCache>			m_disk_cache;
 		BAN::Vector<BAN::RefPtr<Partition>>	m_partitions;
 

kernel/include/kernel/Terminal/TTY.h

@@ -3,7 +3,7 @@
 #include <BAN/Array.h>
 #include <kernel/Device/Device.h>
 #include <kernel/Input/KeyEvent.h>
-#include <kernel/SpinLock.h>
+#include <kernel/Lock/SpinLock.h>
 #include <kernel/Terminal/TerminalDriver.h>
 #include <kernel/Terminal/termios.h>
 #include <kernel/Semaphore.h>
@@ -84,6 +84,8 @@ namespace Kernel
 			Semaphore semaphore;
 		};
 		Buffer m_output;
+
+		RecursiveSpinLock m_write_lock;
 	};
 
 }

kernel/include/kernel/Terminal/VirtualTTY.h

@@ -3,7 +3,6 @@
 #include <BAN/Array.h>
 #include <kernel/Device/Device.h>
 #include <kernel/Input/KeyEvent.h>
-#include <kernel/SpinLock.h>
 #include <kernel/Terminal/TerminalDriver.h>
 #include <kernel/Terminal/termios.h>
 #include <kernel/Terminal/TTY.h>

kernel/kernel/ACPI.cpp

@@ -99,10 +99,10 @@ namespace Kernel
 
 		if (rsdp->revision >= 2)
 		{
-			PageTable::map_fast_page(rsdp->xsdt_address & PAGE_ADDR_MASK);
+			TRY(PageTable::with_fast_page(rsdp->xsdt_address & PAGE_ADDR_MASK,
+				[&]() -> BAN::ErrorOr<void>
+				{
 					auto& xsdt = PageTable::fast_page_as<const XSDT>(rsdp->xsdt_address % PAGE_SIZE);
-			BAN::ScopeGuard _([] { PageTable::unmap_fast_page(); });
-
 					if (memcmp(xsdt.signature, "XSDT", 4) != 0)
 						return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
 					if (!is_valid_std_header(&xsdt))
@@ -111,13 +111,16 @@ namespace Kernel
 					m_header_table_paddr = rsdp->xsdt_address + offsetof(XSDT, entries);
 					m_entry_size = 8;
 					root_entry_count = (xsdt.length - sizeof(SDTHeader)) / 8;
+					return {};
+				}
+			));
 		}
 		else
 		{
-			PageTable::map_fast_page(rsdp->rsdt_address & PAGE_ADDR_MASK);
+			TRY(PageTable::with_fast_page(rsdp->rsdt_address & PAGE_ADDR_MASK,
+				[&]() -> BAN::ErrorOr<void>
+				{
 					auto& rsdt = PageTable::fast_page_as<const RSDT>(rsdp->rsdt_address % PAGE_SIZE);
-			BAN::ScopeGuard _([] { PageTable::unmap_fast_page(); });
-
 					if (memcmp(rsdt.signature, "RSDT", 4) != 0)
 						return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
 					if (!is_valid_std_header(&rsdt))
@@ -126,6 +129,9 @@ namespace Kernel
 					m_header_table_paddr = rsdp->rsdt_address + offsetof(RSDT, entries);
 					m_entry_size = 4;
 					root_entry_count = (rsdt.length - sizeof(SDTHeader)) / 4;
+					return {};
+				}
+			));
 		}
 
 		size_t needed_pages = range_page_count(m_header_table_paddr, root_entry_count * m_entry_size);
@@ -144,9 +150,10 @@ namespace Kernel
 		auto map_header =
 			[](paddr_t header_paddr) -> vaddr_t
 			{
-				PageTable::map_fast_page(header_paddr & PAGE_ADDR_MASK);
+				size_t header_length;
-				size_t header_length = PageTable::fast_page_as<SDTHeader>(header_paddr % PAGE_SIZE).length;
+				PageTable::with_fast_page(header_paddr & PAGE_ADDR_MASK, [&] {
-				PageTable::unmap_fast_page();
+					header_length = PageTable::fast_page_as<SDTHeader>(header_paddr % PAGE_SIZE).length;
+				});
 
 				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);

kernel/kernel/APIC.cpp

@@ -1,8 +1,8 @@
 #include <BAN/ScopeGuard.h>
-#include <kernel/Debug.h>
 #include <kernel/ACPI.h>
 #include <kernel/APIC.h>
 #include <kernel/CPUID.h>
+#include <kernel/Debug.h>
 #include <kernel/IDT.h>
 #include <kernel/Memory/PageTable.h>
 #include <kernel/MMIO.h>

kernel/kernel/Debug.cpp

@@ -1,7 +1,7 @@
 #include <kernel/Debug.h>
 #include <kernel/InterruptController.h>
+#include <kernel/Lock/SpinLock.h>
 #include <kernel/Memory/PageTable.h>
-#include <kernel/SpinLock.h>
 #include <kernel/Terminal/Serial.h>
 #include <kernel/Terminal/TTY.h>
 #include <kernel/Timer/Timer.h>
@@ -13,6 +13,8 @@ extern TerminalDriver* g_terminal_driver;
 namespace Debug
 {
 
+	Kernel::RecursiveSpinLock s_debug_lock;
+
 	void dump_stack_trace()
 	{
 		using namespace Kernel;
@@ -120,18 +122,4 @@ namespace Debug
 		BAN::Formatter::print(Debug::putchar, "[{5}.{3}] {}:{}: ", ms_since_boot / 1000, ms_since_boot % 1000, file, line);
 	}
 
-	static Kernel::RecursiveSpinLock s_debug_lock;
-
-	void DebugLock::lock()
-	{
-		if (Kernel::interrupts_enabled())
-			s_debug_lock.lock();
-	}
-
-	void DebugLock::unlock()
-	{
-		if (Kernel::interrupts_enabled())
-			s_debug_lock.unlock();
-	}
-
 }

kernel/kernel/Device/DebugDevice.cpp

@@ -20,7 +20,7 @@ namespace Kernel
 	BAN::ErrorOr<size_t> DebugDevice::write_impl(off_t, BAN::ConstByteSpan buffer)
 	{
 		auto ms_since_boot = SystemTimer::get().ms_since_boot();
-		Debug::DebugLock::lock();
+		SpinLockGuard _(Debug::s_debug_lock);
 		BAN::Formatter::print(Debug::putchar, "[{5}.{3}] {}: ",
 			ms_since_boot / 1000,
 			ms_since_boot % 1000,
@@ -28,7 +28,6 @@ namespace Kernel
 		);
 		for (size_t i = 0; i < buffer.size(); i++)
 			Debug::putchar(buffer[i]);
-		Debug::DebugLock::unlock();
 		return buffer.size();
 	}
 

kernel/kernel/FS/DevFS/FileSystem.cpp

@@ -5,7 +5,7 @@
 #include <kernel/Device/ZeroDevice.h>
 #include <kernel/FS/DevFS/FileSystem.h>
 #include <kernel/FS/TmpFS/Inode.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Process.h>
 #include <kernel/Scheduler.h>
 #include <kernel/Storage/StorageDevice.h>
@@ -56,12 +56,9 @@ namespace Kernel
 		sync_process->add_thread(MUST(Thread::create_kernel(
 			[](void*)
 			{
-				// NOTE: we lock the device lock here and unlock
-				//       it only while semaphore is blocking
-				s_instance->m_device_lock.lock();
-
 				while (true)
 				{
+					LockGuard _(s_instance->m_device_lock);
 					while (!s_instance->m_should_sync)
 					{
 						LockFreeGuard _(s_instance->m_device_lock);

kernel/kernel/FS/Ext2/FileSystem.cpp

@@ -1,6 +1,6 @@
 #include <BAN/ScopeGuard.h>
 #include <kernel/FS/Ext2/FileSystem.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 
 #define EXT2_DEBUG_PRINT 0
 #define EXT2_VERIFY_INODE 0
@@ -139,7 +139,7 @@ namespace Kernel
 
 	BAN::ErrorOr<uint32_t> Ext2FS::create_inode(const Ext2::Inode& ext2_inode)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(ext2_inode.size == 0);
 
@@ -218,7 +218,7 @@ namespace Kernel
 
 	void Ext2FS::delete_inode(uint32_t ino)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(ino >= superblock().first_ino);
 		ASSERT(ino <= superblock().inodes_count);
@@ -271,7 +271,7 @@ namespace Kernel
 
 	void Ext2FS::read_block(uint32_t block, BlockBufferWrapper& buffer)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		const uint32_t sector_size = m_block_device->blksize();
 		const uint32_t block_size = this->block_size();
@@ -284,7 +284,7 @@ namespace Kernel
 
 	void Ext2FS::write_block(uint32_t block, const BlockBufferWrapper& buffer)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		const uint32_t sector_size = m_block_device->blksize();
 		const uint32_t block_size = this->block_size();
@@ -297,7 +297,7 @@ namespace Kernel
 
 	void Ext2FS::sync_superblock()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		const uint32_t sector_size = m_block_device->blksize();
 		ASSERT(1024 % sector_size == 0);
@@ -322,13 +322,13 @@ namespace Kernel
 
 	Ext2FS::BlockBufferWrapper Ext2FS::get_block_buffer()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		return m_buffer_manager.get_buffer();
 	}
 
 	BAN::ErrorOr<uint32_t> Ext2FS::reserve_free_block(uint32_t primary_bgd)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (m_superblock.r_blocks_count >= m_superblock.free_blocks_count)
 			return BAN::Error::from_errno(ENOSPC);
@@ -389,7 +389,7 @@ namespace Kernel
 
 	void Ext2FS::release_block(uint32_t block)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(block >= m_superblock.first_data_block);
 		ASSERT(block < m_superblock.blocks_count);
@@ -422,7 +422,7 @@ namespace Kernel
 
 	Ext2FS::BlockLocation Ext2FS::locate_inode(uint32_t ino)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(ino <= superblock().inodes_count);
 
@@ -464,7 +464,7 @@ namespace Kernel
 
 	Ext2FS::BlockLocation Ext2FS::locate_block_group_descriptior(uint32_t group_index)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		const uint32_t block_size = this->block_size();
 

kernel/kernel/FS/Inode.cpp

@@ -1,5 +1,5 @@
 #include <kernel/FS/Inode.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 
 #include <fcntl.h>
 
@@ -58,13 +58,13 @@ namespace Kernel
 
 	void Inode::on_close()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		on_close_impl();
 	}
 
 	BAN::ErrorOr<BAN::RefPtr<Inode>> Inode::find_inode(BAN::StringView name)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
 		return find_inode_impl(name);
@@ -72,7 +72,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Inode::list_next_inodes(off_t offset, DirectoryEntryList* list, size_t list_len)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
 		return list_next_inodes_impl(offset, list, list_len);
@@ -80,7 +80,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Inode::create_file(BAN::StringView name, mode_t mode, uid_t uid, gid_t gid)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!this->mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
 		if (Mode(mode).ifdir())
@@ -90,7 +90,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Inode::create_directory(BAN::StringView name, mode_t mode, uid_t uid, gid_t gid)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!this->mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
 		if (!Mode(mode).ifdir())
@@ -100,7 +100,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Inode::unlink(BAN::StringView name)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
 		if (name == "."sv || name == ".."sv)
@@ -110,7 +110,7 @@ namespace Kernel
 
 	BAN::ErrorOr<BAN::String> Inode::link_target()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().iflnk())
 			return BAN::Error::from_errno(EINVAL);
 		return link_target_impl();
@@ -118,7 +118,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Inode::accept(sockaddr* address, socklen_t* address_len)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifsock())
 			return BAN::Error::from_errno(ENOTSOCK);
 		return accept_impl(address, address_len);
@@ -126,7 +126,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Inode::bind(const sockaddr* address, socklen_t address_len)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifsock())
 			return BAN::Error::from_errno(ENOTSOCK);
 		return bind_impl(address, address_len);
@@ -134,7 +134,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Inode::connect(const sockaddr* address, socklen_t address_len)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifsock())
 			return BAN::Error::from_errno(ENOTSOCK);
 		return connect_impl(address, address_len);
@@ -142,7 +142,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Inode::listen(int backlog)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifsock())
 			return BAN::Error::from_errno(ENOTSOCK);
 		return listen_impl(backlog);
@@ -150,7 +150,7 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> Inode::sendto(BAN::ConstByteSpan message, const sockaddr* address, socklen_t address_len)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifsock())
 			return BAN::Error::from_errno(ENOTSOCK);
 		return sendto_impl(message, address, address_len);
@@ -158,7 +158,7 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> Inode::recvfrom(BAN::ByteSpan buffer, sockaddr* address, socklen_t* address_len)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (!mode().ifsock())
 			return BAN::Error::from_errno(ENOTSOCK);
 		return recvfrom_impl(buffer, address, address_len);
@@ -166,7 +166,7 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> Inode::read(off_t offset, BAN::ByteSpan buffer)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (mode().ifdir())
 			return BAN::Error::from_errno(EISDIR);
 		return read_impl(offset, buffer);
@@ -174,7 +174,7 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> Inode::write(off_t offset, BAN::ConstByteSpan buffer)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (mode().ifdir())
 			return BAN::Error::from_errno(EISDIR);
 		return write_impl(offset, buffer);
@@ -182,7 +182,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Inode::truncate(size_t size)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (mode().ifdir())
 			return BAN::Error::from_errno(EISDIR);
 		return truncate_impl(size);
@@ -191,37 +191,37 @@ namespace Kernel
 	BAN::ErrorOr<void> Inode::chmod(mode_t mode)
 	{
 		ASSERT((mode & Inode::Mode::TYPE_MASK) == 0);
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		return chmod_impl(mode);
 	}
 
 	BAN::ErrorOr<void> Inode::chown(uid_t uid, gid_t gid)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		return chown_impl(uid, gid);
 	}
 
 	bool Inode::can_read() const
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		return can_read_impl();
 	}
 
 	bool Inode::can_write() const
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		return can_write_impl();
 	}
 
 	bool Inode::has_error() const
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		return has_error_impl();
 	}
 
 	BAN::ErrorOr<long> Inode::ioctl(int request, void* arg)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		return ioctl_impl(request, arg);
 	}
 

kernel/kernel/FS/Pipe.cpp

@@ -1,5 +1,5 @@
 #include <kernel/FS/Pipe.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Thread.h>
 #include <kernel/Timer/Timer.h>
 
@@ -26,14 +26,14 @@ namespace Kernel
 
 	void Pipe::clone_writing()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		ASSERT(m_writing_count > 0);
 		m_writing_count++;
 	}
 
 	void Pipe::close_writing()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		ASSERT(m_writing_count > 0);
 		m_writing_count--;
 		if (m_writing_count == 0)
@@ -42,12 +42,12 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> Pipe::read_impl(off_t, BAN::ByteSpan buffer)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		while (m_buffer.empty())
 		{
 			if (m_writing_count == 0)
 				return 0;
-			LockFreeGuard lock_free(m_lock);
+			LockFreeGuard lock_free(m_mutex);
 			TRY(Thread::current().block_or_eintr_indefinite(m_semaphore));
 		}
 
@@ -66,7 +66,7 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> Pipe::write_impl(off_t, BAN::ConstByteSpan buffer)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		size_t old_size = m_buffer.size();
 

kernel/kernel/FS/ProcFS/FileSystem.cpp

@@ -1,6 +1,6 @@
 #include <kernel/FS/ProcFS/FileSystem.h>
 #include <kernel/FS/ProcFS/Inode.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 
 namespace Kernel
 {

kernel/kernel/FS/TmpFS/FileSystem.cpp

@@ -66,7 +66,7 @@ namespace Kernel
 
 	BAN::ErrorOr<BAN::RefPtr<TmpInode>> TmpFileSystem::open_inode(ino_t ino)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (m_inode_cache.contains(ino))
 			return m_inode_cache[ino];
@@ -85,7 +85,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> TmpFileSystem::add_to_cache(BAN::RefPtr<TmpInode> inode)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (!m_inode_cache.contains(inode->ino()))
 			TRY(m_inode_cache.insert(inode->ino(), inode));
@@ -94,7 +94,7 @@ namespace Kernel
 
 	void TmpFileSystem::remove_from_cache(BAN::RefPtr<TmpInode> inode)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(m_inode_cache.contains(inode->ino()));
 		m_inode_cache.remove(inode->ino());
@@ -102,7 +102,7 @@ namespace Kernel
 
 	void TmpFileSystem::read_inode(ino_t ino, TmpInodeInfo& out)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		auto inode_location = find_inode(ino);
 		PageTable::with_fast_page(inode_location.paddr, [&] {
@@ -112,7 +112,7 @@ namespace Kernel
 
 	void TmpFileSystem::write_inode(ino_t ino, const TmpInodeInfo& info)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		auto inode_location = find_inode(ino);
 		PageTable::with_fast_page(inode_location.paddr, [&] {
@@ -123,7 +123,7 @@ namespace Kernel
 
 	void TmpFileSystem::delete_inode(ino_t ino)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		auto inode_location = find_inode(ino);
 		PageTable::with_fast_page(inode_location.paddr, [&] {
@@ -138,7 +138,7 @@ namespace Kernel
 
 	BAN::ErrorOr<ino_t> TmpFileSystem::allocate_inode(const TmpInodeInfo& info)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		constexpr size_t inodes_per_page = PAGE_SIZE / sizeof(TmpInodeInfo);
 
@@ -164,7 +164,7 @@ namespace Kernel
 
 	TmpFileSystem::InodeLocation TmpFileSystem::find_inode(ino_t ino)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT_GTE(ino, first_inode);
 		ASSERT_LT(ino, max_inodes);
@@ -182,7 +182,7 @@ namespace Kernel
 
 	void TmpFileSystem::free_block(size_t index)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		constexpr size_t addresses_per_page = PAGE_SIZE / sizeof(PageInfo);
 
@@ -204,7 +204,7 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> TmpFileSystem::allocate_block()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		size_t result = first_data_page;
 		TRY(for_each_indirect_paddr_allocating(m_data_pages, [&] (paddr_t, bool allocated) {
@@ -218,7 +218,7 @@ namespace Kernel
 
 	paddr_t TmpFileSystem::find_block(size_t index)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT_GT(index, 0);
 		return find_indirect(m_data_pages, index - first_data_page, 3);
@@ -226,7 +226,7 @@ namespace Kernel
 
 	paddr_t TmpFileSystem::find_indirect(PageInfo root, size_t index, size_t depth)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(root.flags() & PageInfo::Flags::Present);
 		if (depth == 0)
@@ -257,7 +257,7 @@ namespace Kernel
 	template<TmpFuncs::for_each_indirect_paddr_allocating_callback F>
 	BAN::ErrorOr<BAN::Iteration> TmpFileSystem::for_each_indirect_paddr_allocating_internal(PageInfo page_info, F callback, size_t depth)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(page_info.flags() & PageInfo::Flags::Present);
 		if (depth == 0)
@@ -316,7 +316,7 @@ namespace Kernel
 	template<TmpFuncs::for_each_indirect_paddr_allocating_callback F>
 	BAN::ErrorOr<void> TmpFileSystem::for_each_indirect_paddr_allocating(PageInfo page_info, F callback, size_t depth)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		BAN::Iteration result = TRY(for_each_indirect_paddr_allocating_internal(page_info, callback, depth));
 		ASSERT(result == BAN::Iteration::Break);

kernel/kernel/FS/VirtualFileSystem.cpp

@@ -5,7 +5,7 @@
 #include <kernel/FS/ProcFS/FileSystem.h>
 #include <kernel/FS/TmpFS/FileSystem.h>
 #include <kernel/FS/VirtualFileSystem.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <fcntl.h>
 
 namespace Kernel
@@ -63,15 +63,14 @@ namespace Kernel
 		if (!file.inode->mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		TRY(m_mount_points.push_back({ file, file_system }));
-
 		return {};
 	}
 
 	VirtualFileSystem::MountPoint* VirtualFileSystem::mount_from_host_inode(BAN::RefPtr<Inode> inode)
 	{
-		ASSERT(m_lock.is_locked());
+		LockGuard _(m_mutex);
 		for (MountPoint& mount : m_mount_points)
 			if (*mount.host.inode == *inode)
 				return &mount;
@@ -80,7 +79,7 @@ namespace Kernel
 
 	VirtualFileSystem::MountPoint* VirtualFileSystem::mount_from_root_inode(BAN::RefPtr<Inode> inode)
 	{
-		ASSERT(m_lock.is_locked());
+		LockGuard _(m_mutex);
 		for (MountPoint& mount : m_mount_points)
 			if (*mount.target->root_inode() == *inode)
 				return &mount;
@@ -89,7 +88,7 @@ namespace Kernel
 
 	BAN::ErrorOr<VirtualFileSystem::File> VirtualFileSystem::file_from_absolute_path(const Credentials& credentials, BAN::StringView path, int flags)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(path.front() == '/');
 

kernel/kernel/Input/PS2/Controller.cpp

@@ -22,7 +22,7 @@ namespace Kernel::Input
 	BAN::ErrorOr<void> PS2Controller::send_byte(uint16_t port, uint8_t byte)
 	{
 		ASSERT(interrupts_enabled());
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		uint64_t timeout = SystemTimer::get().ms_since_boot() + s_ps2_timeout_ms;
 		while (SystemTimer::get().ms_since_boot() < timeout)
 		{
@@ -37,7 +37,7 @@ namespace Kernel::Input
 	BAN::ErrorOr<uint8_t> PS2Controller::read_byte()
 	{
 		ASSERT(interrupts_enabled());
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		uint64_t timeout = SystemTimer::get().ms_since_boot() + s_ps2_timeout_ms;
 		while (SystemTimer::get().ms_since_boot() < timeout)
 		{
@@ -50,14 +50,14 @@ namespace Kernel::Input
 
 	BAN::ErrorOr<void> PS2Controller::send_command(PS2::Command command)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		TRY(send_byte(PS2::IOPort::COMMAND, command));
 		return {};
 	}
 
 	BAN::ErrorOr<void> PS2Controller::send_command(PS2::Command command, uint8_t data)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		TRY(send_byte(PS2::IOPort::COMMAND, command));
 		TRY(send_byte(PS2::IOPort::DATA, data));
 		return {};
@@ -65,7 +65,7 @@ namespace Kernel::Input
 
 	BAN::ErrorOr<void> PS2Controller::device_send_byte(uint8_t device_index, uint8_t byte)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (device_index == 1)
 			TRY(send_byte(PS2::IOPort::COMMAND, PS2::Command::WRITE_TO_SECOND_PORT));
 		TRY(send_byte(PS2::IOPort::DATA, byte));
@@ -74,7 +74,7 @@ namespace Kernel::Input
 
 	BAN::ErrorOr<void> PS2Controller::device_send_byte_and_wait_ack(uint8_t device_index, uint8_t byte)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		for (;;)
 		{
 			TRY(device_send_byte(device_index, byte));

kernel/kernel/InterruptController.cpp

@@ -67,11 +67,4 @@ namespace Kernel
 			dwarnln("could not enter acpi mode");
 	}
 
-	bool interrupts_enabled()
-	{
-		uintptr_t flags;
-		asm volatile("pushf; pop %0" : "=r"(flags) :: "memory");
-		return flags & (1 << 9);
-	}
-
 }

kernel/kernel/Lock/SpinLock.cpp

@@ -0,0 +1,64 @@
+#include <kernel/InterruptController.h>
+#include <kernel/Lock/SpinLock.h>
+#include <kernel/Scheduler.h>
+
+// FIXME: try to move these to header
+
+namespace Kernel
+{
+
+	InterruptState SpinLock::lock()
+	{
+		auto tid = Scheduler::current_tid();
+		ASSERT_NEQ(m_locker.load(), tid);
+
+		InterruptState state = interrupts_enabled();
+		DISABLE_INTERRUPTS();
+
+		if (!m_locker.compare_exchange(-1, tid))
+			ASSERT_NOT_REACHED();
+
+		return state;
+	}
+
+	void SpinLock::unlock(InterruptState state)
+	{
+		ASSERT_EQ(m_locker.load(), Scheduler::current_tid());
+		m_locker.store(-1);
+		if (state)
+			ENABLE_INTERRUPTS();
+	}
+
+	InterruptState RecursiveSpinLock::lock()
+	{
+		auto tid = Scheduler::current_tid();
+
+		InterruptState state = interrupts_enabled();
+		DISABLE_INTERRUPTS();
+
+		if (tid == m_locker)
+			ASSERT_GT(m_lock_depth, 0);
+		else
+		{
+			if (!m_locker.compare_exchange(-1, tid))
+				ASSERT_NOT_REACHED();
+			ASSERT_EQ(m_lock_depth, 0);
+		}
+
+		m_lock_depth++;
+
+		return state;
+	}
+
+	void RecursiveSpinLock::unlock(InterruptState state)
+	{
+		auto tid = Scheduler::current_tid();
+		ASSERT_EQ(m_locker.load(), tid);
+		ASSERT_GT(m_lock_depth, 0);
+		if (--m_lock_depth == 0)
+			m_locker = -1;
+		if (state)
+			ENABLE_INTERRUPTS();
+	}
+
+}

kernel/kernel/Memory/FileBackedRegion.cpp

@@ -1,5 +1,5 @@
 #include <kernel/CriticalScope.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Memory/FileBackedRegion.h>
 #include <kernel/Memory/Heap.h>
 
@@ -26,7 +26,7 @@ namespace Kernel
 
 		if (type == Type::SHARED)
 		{
-			LockGuard _(inode->m_lock);
+			LockGuard _(inode->m_mutex);
 			if (inode->m_shared_region.valid())
 				region->m_shared_data = inode->m_shared_region.lock();
 			else
@@ -157,7 +157,7 @@ namespace Kernel
 		}
 		else if	(m_type == Type::SHARED)
 		{
-			LockGuard _(m_inode->m_lock);
+			LockGuard _(m_inode->m_mutex);
 			ASSERT(m_inode->m_shared_region.valid());
 			ASSERT(m_shared_data->pages.size() == BAN::Math::div_round_up<size_t>(m_inode->size(), PAGE_SIZE));
 
@@ -175,10 +175,9 @@ namespace Kernel
 
 				TRY(m_inode->read(offset, BAN::ByteSpan(m_shared_data->page_buffer, bytes)));
 
-				CriticalScope _;
+				PageTable::with_fast_page(pages[page_index], [&] {
-				PageTable::map_fast_page(pages[page_index]);
 					memcpy(PageTable::fast_page_as_ptr(), m_shared_data->page_buffer, PAGE_SIZE);
-				PageTable::unmap_fast_page();
+				});
 			}
 
 			paddr_t paddr = pages[page_index];

kernel/kernel/Memory/Heap.cpp

@@ -1,5 +1,4 @@
 #include <kernel/BootInfo.h>
-#include <kernel/LockGuard.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/PageTable.h>
 
@@ -67,7 +66,7 @@ namespace Kernel
 
 	paddr_t Heap::take_free_page()
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		for (auto& range : m_physical_ranges)
 			if (range.free_pages() >= 1)
 				return range.reserve_page();
@@ -76,7 +75,7 @@ namespace Kernel
 
 	void Heap::release_page(paddr_t paddr)
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		for (auto& range : m_physical_ranges)
 			if (range.contains(paddr))
 				return range.release_page(paddr);
@@ -85,7 +84,7 @@ namespace Kernel
 
 	paddr_t Heap::take_free_contiguous_pages(size_t pages)
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		for (auto& range : m_physical_ranges)
 			if (range.free_pages() >= pages)
 				if (paddr_t paddr = range.reserve_contiguous_pages(pages))
@@ -95,7 +94,7 @@ namespace Kernel
 
 	void Heap::release_contiguous_pages(paddr_t paddr, size_t pages)
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		for (auto& range : m_physical_ranges)
 			if (range.contains(paddr))
 				return range.release_contiguous_pages(paddr, pages);
@@ -104,7 +103,7 @@ namespace Kernel
 
 	size_t Heap::used_pages() const
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		size_t result = 0;
 		for (const auto& range : m_physical_ranges)
 			result += range.used_pages();
@@ -113,7 +112,7 @@ namespace Kernel
 
 	size_t Heap::free_pages() const
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_lock);
 		size_t result = 0;
 		for (const auto& range : m_physical_ranges)
 			result += range.free_pages();

kernel/kernel/Memory/MemoryBackedRegion.cpp

@@ -1,5 +1,5 @@
 #include <kernel/CriticalScope.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/MemoryBackedRegion.h>
 
@@ -57,15 +57,9 @@ namespace Kernel
 		m_page_table.map_page_at(paddr, vaddr, m_flags);
 
 		// Zero out the new page
-		if (&PageTable::current() == &m_page_table)
+		PageTable::with_fast_page(paddr, [&] {
-			memset((void*)vaddr, 0x00, PAGE_SIZE);
-		else
-		{
-			CriticalScope _;
-			PageTable::map_fast_page(paddr);
 			memset(PageTable::fast_page_as_ptr(), 0x00, PAGE_SIZE);
-			PageTable::unmap_fast_page();
+		});
-		}
 
 		return true;
 	}
@@ -100,15 +94,9 @@ namespace Kernel
 
 			TRY(allocate_page_containing(write_vaddr));
 
-			if (&PageTable::current() == &m_page_table)
+			PageTable::with_fast_page(m_page_table.physical_address_of(write_vaddr & PAGE_ADDR_MASK), [&] {
-				memcpy((void*)write_vaddr, (void*)(buffer + written), bytes);
-			else
-			{
-				CriticalScope _;
-				PageTable::map_fast_page(m_page_table.physical_address_of(write_vaddr & PAGE_ADDR_MASK));
 				memcpy(PageTable::fast_page_as_ptr(page_offset), (void*)(buffer + written), bytes);
-				PageTable::unmap_fast_page();
+			});
-			}
 
 			written += bytes;
 		}

kernel/kernel/Memory/VirtualRange.cpp

@@ -1,5 +1,5 @@
 #include <kernel/CriticalScope.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/VirtualRange.h>
 
@@ -68,7 +68,7 @@ namespace Kernel
 		}
 		ASSERT(vaddr + size <= vaddr_end);
 
-		LockGuard _(page_table);
+		SpinLockGuard _(page_table);
 		page_table.unmap_range(vaddr, size); // We have to unmap here to allow reservation in create_to_vaddr()
 		return create_to_vaddr(page_table, vaddr, size, flags, preallocate_pages);
 	}
@@ -99,7 +99,7 @@ namespace Kernel
 
 		auto result = TRY(create_to_vaddr(page_table, vaddr(), size(), flags(), m_preallocated));
 
-		LockGuard _(m_page_table);
+		SpinLockGuard _(m_page_table);
 		for (size_t offset = 0; offset < size(); offset += PAGE_SIZE)
 		{
 			if (!m_preallocated && m_page_table.physical_address_of(vaddr() + offset))
@@ -110,10 +110,9 @@ namespace Kernel
 				result->m_page_table.map_page_at(paddr, vaddr() + offset, m_flags);
 			}
 
-			CriticalScope _;
+			PageTable::with_fast_page(result->m_page_table.physical_address_of(vaddr() + offset), [&] {
-			PageTable::map_fast_page(result->m_page_table.physical_address_of(vaddr() + offset));
 				memcpy(PageTable::fast_page_as_ptr(), (void*)(vaddr() + offset), PAGE_SIZE);
-			PageTable::unmap_fast_page();
+			});
 		}
 
 		return result;
@@ -148,10 +147,9 @@ namespace Kernel
 
 		for (size_t offset = 0; offset < size(); offset += PAGE_SIZE)
 		{
-			CriticalScope _;
+			PageTable::with_fast_page(m_page_table.physical_address_of(vaddr() + offset), [&] {
-			PageTable::map_fast_page(m_page_table.physical_address_of(vaddr() + offset));
 				memset(PageTable::fast_page_as_ptr(), 0x00, PAGE_SIZE);
-			PageTable::unmap_fast_page();
+			});
 		}
 	}
 
@@ -176,12 +174,9 @@ namespace Kernel
 
 		while (bytes > 0)
 		{
-			{
+			PageTable::with_fast_page(m_page_table.physical_address_of(vaddr() + page_index * PAGE_SIZE), [&] {
-				CriticalScope _;
-				PageTable::map_fast_page(m_page_table.physical_address_of(vaddr() + page_index * PAGE_SIZE));
 				memcpy(PageTable::fast_page_as_ptr(page_offset), buffer, PAGE_SIZE - page_offset);
-				PageTable::unmap_fast_page();
+			});
-			}
 
 			buffer += PAGE_SIZE - page_offset;
 			bytes  -= PAGE_SIZE - page_offset;

kernel/kernel/Networking/ARPTable.cpp

@@ -1,4 +1,3 @@
-#include <kernel/LockGuard.h>
 #include <kernel/Networking/ARPTable.h>
 #include <kernel/Scheduler.h>
 #include <kernel/Timer/Timer.h>
@@ -52,9 +51,10 @@ namespace Kernel
 			ipv4_address = interface.get_gateway();
 
 		{
-			LockGuard _(m_lock);
+			SpinLockGuard _(m_table_lock);
-			if (m_arp_table.contains(ipv4_address))
+			auto it = m_arp_table.find(ipv4_address);
-				return m_arp_table[ipv4_address];
+			if (it != m_arp_table.end())
+				return it->value;
 		}
 
 		ARPPacket arp_request;
@@ -74,9 +74,10 @@ namespace Kernel
 		while (SystemTimer::get().ms_since_boot() < timeout)
 		{
 			{
-				LockGuard _(m_lock);
+				SpinLockGuard _(m_table_lock);
-				if (m_arp_table.contains(ipv4_address))
+				auto it = m_arp_table.find(ipv4_address);
-					return m_arp_table[ipv4_address];
+				if (it != m_arp_table.end())
+					return it->value;
 			}
 			Scheduler::get().reschedule();
 		}
@@ -114,13 +115,15 @@ namespace Kernel
 			}
 			case ARPOperation::Reply:
 			{
-				LockGuard _(m_lock);
+				SpinLockGuard _(m_table_lock);
-				if (m_arp_table.contains(packet.spa))
+				auto it = m_arp_table.find(packet.spa);
+
+				if (it != m_arp_table.end())
 				{
-					if (m_arp_table[packet.spa] != packet.sha)
+					if (it->value != packet.sha)
 					{
 						dprintln("Update IPv4 {} MAC to {}", packet.spa, packet.sha);
-						m_arp_table[packet.spa] = packet.sha;
+						it->value = packet.sha;
 					}
 				}
 				else

kernel/kernel/Networking/IPv4Layer.cpp

@@ -70,12 +70,14 @@ namespace Kernel
 
 	void IPv4Layer::unbind_socket(BAN::RefPtr<NetworkSocket> socket, uint16_t port)
 	{
-		LockGuard _(m_lock);
-		if (m_bound_sockets.contains(port))
 		{
-			ASSERT(m_bound_sockets[port].valid());
+			SpinLockGuard _(m_bound_socket_lock);
-			ASSERT(m_bound_sockets[port].lock() == socket);
+			auto it = m_bound_sockets.find(port);
-			m_bound_sockets.remove(port);
+			if (it != m_bound_sockets.end())
+			{
+				ASSERT(it->value.lock() == socket);
+				m_bound_sockets.remove(it);
+			}
 		}
 		NetworkManager::get().TmpFileSystem::remove_from_cache(socket);
 	}
@@ -88,7 +90,7 @@ namespace Kernel
 			return BAN::Error::from_errno(EAFNOSUPPORT);
 		auto& sockaddr_in = *reinterpret_cast<const struct sockaddr_in*>(address);
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_bound_socket_lock);
 
 		uint16_t port = NetworkSocket::PORT_NONE;
 		for (uint32_t i = 0; i < 100 && port == NetworkSocket::PORT_NONE; i++)
@@ -124,7 +126,7 @@ namespace Kernel
 		auto& sockaddr_in = *reinterpret_cast<const struct sockaddr_in*>(address);
 		uint16_t port = BAN::host_to_network_endian(sockaddr_in.sin_port);
 
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_bound_socket_lock);
 
 		if (m_bound_sockets.contains(port))
 			return BAN::Error::from_errno(EADDRINUSE);
@@ -250,13 +252,14 @@ namespace Kernel
 		BAN::RefPtr<Kernel::NetworkSocket> bound_socket;
 
 		{
-			LockGuard _(m_lock);
+			SpinLockGuard _(m_bound_socket_lock);
-			if (!m_bound_sockets.contains(dst_port))
+			auto it = m_bound_sockets.find(dst_port);
+			if (it == m_bound_sockets.end())
 			{
 				dprintln_if(DEBUG_IPV4, "no one is listening on port {}", dst_port);
 				return {};
 			}
-			bound_socket = m_bound_sockets[dst_port].lock();
+			bound_socket = it->value.lock();
 		}
 
 		if (!bound_socket)

kernel/kernel/Networking/TCPSocket.cpp

@@ -1,4 +1,4 @@
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Networking/TCPSocket.h>
 #include <kernel/Random.h>
 #include <kernel/Timer/Timer.h>
@@ -68,7 +68,7 @@ namespace Kernel
 
 	void TCPSocket::on_close_impl()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (!is_bound())
 			return;
@@ -103,7 +103,7 @@ namespace Kernel
 		if (address_len > (socklen_t)sizeof(sockaddr_storage))
 			address_len = sizeof(sockaddr_storage);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(!m_connection_info.has_value());
 
@@ -139,7 +139,7 @@ namespace Kernel
 		uint64_t wake_time_ms = SystemTimer::get().ms_since_boot() + 5000;
 		while (m_state != State::Established)
 		{
-			LockFreeGuard free(m_lock);
+			LockFreeGuard free(m_mutex);
 			if (SystemTimer::get().ms_since_boot() >= wake_time_ms)
 				return BAN::Error::from_errno(ECONNREFUSED);
 			TRY(Thread::current().block_or_eintr_or_waketime(m_semaphore, wake_time_ms, true));
@@ -212,7 +212,7 @@ namespace Kernel
 		{
 			case State::Closed:
 			{
-				LockGuard _(m_lock);
+				LockGuard _(m_mutex);
 				header.syn = 1;
 				add_tcp_header_option<0, TCPOption::MaximumSeqmentSize>(header, m_interface->payload_mtu() - m_network_layer.header_size());
 				add_tcp_header_option<4, TCPOption::WindowScale>(header, 0);
@@ -233,7 +233,7 @@ namespace Kernel
 				break;
 			case State::CloseWait:
 			{
-				LockGuard _(m_lock);
+				LockGuard _(m_mutex);
 				header.ack = 1;
 				header.fin = 1;
 				m_state = State::LastAck;
@@ -242,7 +242,7 @@ namespace Kernel
 			}
 			case State::FinWait1:
 			{
-				LockGuard _(m_lock);
+				LockGuard _(m_mutex);
 				header.ack = 1;
 				header.fin = 1;
 				m_state = State::FinWait2;
@@ -250,7 +250,7 @@ namespace Kernel
 			}
 			case State::FinWait2:
 			{
-				LockGuard _(m_lock);
+				LockGuard _(m_mutex);
 				header.ack = 1;
 				m_state = State::TimeWait;
 				m_time_wait_start_ms = SystemTimer::get().ms_since_boot();
@@ -312,7 +312,7 @@ namespace Kernel
 				if (!header.ack || !header.syn)
 					break;
 
-				LockGuard _(m_lock);
+				LockGuard _(m_mutex);
 
 				if (header.ack_number != m_send_window.current_seq)
 				{
@@ -345,7 +345,7 @@ namespace Kernel
 				if (!header.ack)
 					break;
 
-				LockGuard _(m_lock);
+				LockGuard _(m_mutex);
 
 				if (header.fin)
 				{
@@ -436,7 +436,7 @@ namespace Kernel
 				set_connection_as_closed();
 
 			{
-				LockGuard _(m_lock);
+				LockGuard _(m_mutex);
 
 				if (m_should_ack)
 				{
@@ -518,7 +518,7 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> TCPSocket::recvfrom_impl(BAN::ByteSpan buffer, sockaddr*, socklen_t*)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (m_state == State::Closed)
 			return BAN::Error::from_errno(ENOTCONN);
@@ -542,7 +542,7 @@ namespace Kernel
 				case State::Closing:	ASSERT_NOT_REACHED();
 			};
 
-			LockFreeGuard free(m_lock);
+			LockFreeGuard free(m_mutex);
 			TRY(Thread::current().block_or_eintr_indefinite(m_semaphore));
 		}
 
@@ -575,7 +575,7 @@ namespace Kernel
 			return message.size();
 		}
 
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (m_state == State::Closed)
 			return BAN::Error::from_errno(ENOTCONN);
@@ -602,7 +602,7 @@ namespace Kernel
 			if (m_send_window.data_size + message.size() <= m_send_window.buffer->size())
 				break;
 
-			LockFreeGuard free(m_lock);
+			LockFreeGuard free(m_mutex);
 			TRY(Thread::current().block_or_eintr_indefinite(m_semaphore));
 		}
 
@@ -634,7 +634,7 @@ namespace Kernel
 				case State::Closing:	ASSERT_NOT_REACHED();
 			};
 
-			LockFreeGuard free(m_lock);
+			LockFreeGuard free(m_mutex);
 			TRY(Thread::current().block_or_eintr_indefinite(m_semaphore));
 		}
 

kernel/kernel/Networking/UDPSocket.cpp

@@ -1,4 +1,3 @@
-#include <kernel/LockGuard.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Networking/UDPSocket.h>
 #include <kernel/Thread.h>
@@ -46,7 +45,7 @@ namespace Kernel
 		//auto& header = packet.as<const UDPHeader>();
 		auto payload = packet.slice(sizeof(UDPHeader));
 
-		LockGuard _(m_packet_lock);
+		SpinLockGuard _(m_packet_lock);
 
 		if (m_packets.full())
 		{
@@ -88,12 +87,12 @@ namespace Kernel
 		}
 		ASSERT(m_port != PORT_NONE);
 
-		LockGuard _(m_packet_lock);
+		auto state = m_packet_lock.lock();
-
 		while (m_packets.empty())
 		{
-			LockFreeGuard free(m_packet_lock);
+			m_packet_lock.unlock(state);
 			TRY(Thread::current().block_or_eintr_indefinite(m_packet_semaphore));
+			state = m_packet_lock.lock();
 		}
 
 		auto packet_info = m_packets.front();
@@ -115,6 +114,8 @@ namespace Kernel
 
 		m_packet_total_size -= packet_info.packet_size;
 
+		m_packet_lock.unlock(state);
+
 		if (address && address_len)
 		{
 			if (*address_len > (socklen_t)sizeof(sockaddr_storage))

kernel/kernel/Networking/UNIX/Socket.cpp

@@ -51,9 +51,10 @@ namespace Kernel
 	{
 		if (is_bound() && !is_bound_to_unused())
 		{
-			LockGuard _(s_bound_socket_lock);
+			SpinLockGuard _(s_bound_socket_lock);
-			if (s_bound_sockets.contains(m_bound_path))
+			auto it = s_bound_sockets.find(m_bound_path);
-				s_bound_sockets.remove(m_bound_path);
+			if (it != s_bound_sockets.end())
+				s_bound_sockets.remove(it);
 		}
 	}
 
@@ -71,7 +72,7 @@ namespace Kernel
 		BAN::RefPtr<UnixDomainSocket> pending;
 
 		{
-			LockGuard _(connection_info.pending_lock);
+			SpinLockGuard _(connection_info.pending_lock);
 			pending = connection_info.pending_connections.front();
 			connection_info.pending_connections.pop();
 			connection_info.pending_semaphore.unblock();
@@ -120,10 +121,11 @@ namespace Kernel
 		BAN::RefPtr<UnixDomainSocket> target;
 
 		{
-			LockGuard _(s_bound_socket_lock);
+			SpinLockGuard _(s_bound_socket_lock);
-			if (!s_bound_sockets.contains(file.canonical_path))
+			auto it = s_bound_sockets.find(file.canonical_path);
+			if (it == s_bound_sockets.end())
 				return BAN::Error::from_errno(ECONNREFUSED);
-			target = s_bound_sockets[file.canonical_path].lock();
+			target = it->value.lock();
 			if (!target)
 				return BAN::Error::from_errno(ECONNREFUSED);
 		}
@@ -150,7 +152,7 @@ namespace Kernel
 		{
 			auto& target_info = target->m_info.get<ConnectionInfo>();
 			{
-				LockGuard _(target_info.pending_lock);
+				SpinLockGuard _(target_info.pending_lock);
 				if (target_info.pending_connections.size() < target_info.pending_connections.capacity())
 				{
 					MUST(target_info.pending_connections.push(this));
@@ -205,7 +207,7 @@ namespace Kernel
 			O_RDWR
 		));
 
-		LockGuard _(s_bound_socket_lock);
+		SpinLockGuard _(s_bound_socket_lock);
 		ASSERT(!s_bound_sockets.contains(file.canonical_path));
 		TRY(s_bound_sockets.emplace(file.canonical_path, TRY(get_weak_ptr())));
 		m_bound_path = BAN::move(file.canonical_path);
@@ -229,12 +231,12 @@ namespace Kernel
 
 	BAN::ErrorOr<void> UnixDomainSocket::add_packet(BAN::ConstByteSpan packet)
 	{
-		LockGuard _(m_lock);
+		auto state = m_packet_lock.lock();
-
 		while (m_packet_sizes.full() || m_packet_size_total + packet.size() > s_packet_buffer_size)
 		{
-			LockFreeGuard _(m_lock);
+			m_packet_lock.unlock(state);
 			TRY(Thread::current().block_or_eintr_indefinite(m_packet_semaphore));
+			state = m_packet_lock.lock();
 		}
 
 		uint8_t* packet_buffer = reinterpret_cast<uint8_t*>(m_packet_buffer->vaddr() + m_packet_size_total);
@@ -245,6 +247,7 @@ namespace Kernel
 			m_packet_sizes.push(packet.size());
 
 		m_packet_semaphore.unblock();
+		m_packet_lock.unlock(state);
 		return {};
 	}
 
@@ -318,10 +321,11 @@ namespace Kernel
 				canonical_path = BAN::move(file.canonical_path);
 			}
 
-			LockGuard _(s_bound_socket_lock);
+			SpinLockGuard _(s_bound_socket_lock);
-			if (!s_bound_sockets.contains(canonical_path))
+			auto it = s_bound_sockets.find(canonical_path);
+			if (it == s_bound_sockets.end())
 				return BAN::Error::from_errno(EDESTADDRREQ);
-			auto target = s_bound_sockets[canonical_path].lock();
+			auto target = it->value.lock();
 			if (!target)
 				return BAN::Error::from_errno(EDESTADDRREQ);
 			TRY(target->add_packet(message));
@@ -338,10 +342,12 @@ namespace Kernel
 				return BAN::Error::from_errno(ENOTCONN);
 		}
 
+		auto state = m_packet_lock.lock();
 		while (m_packet_size_total == 0)
 		{
-			LockFreeGuard _(m_lock);
+			m_packet_lock.unlock(state);
 			TRY(Thread::current().block_or_eintr_indefinite(m_packet_semaphore));
+			state = m_packet_lock.lock();
 		}
 
 		uint8_t* packet_buffer = reinterpret_cast<uint8_t*>(m_packet_buffer->vaddr());
@@ -360,6 +366,7 @@ namespace Kernel
 		m_packet_size_total -= nread;
 
 		m_packet_semaphore.unblock();
+		m_packet_lock.unlock(state);
 
 		return nread;
 	}

kernel/kernel/Process.cpp

@@ -7,11 +7,10 @@
 #include <kernel/IDT.h>
 #include <kernel/Input/KeyboardLayout.h>
 #include <kernel/InterruptController.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Memory/FileBackedRegion.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/MemoryBackedRegion.h>
-#include <kernel/Memory/PageTableScope.h>
 #include <kernel/Process.h>
 #include <kernel/Scheduler.h>
 #include <kernel/Storage/StorageDevice.h>
@@ -33,9 +32,9 @@ namespace Kernel
 	static BAN::Vector<Process*> s_processes;
 	static RecursiveSpinLock s_process_lock;
 
-	void Process::for_each_process(const BAN::Function<BAN::Iteration(Process&)>& callback)
+	static void for_each_process(const BAN::Function<BAN::Iteration(Process&)>& callback)
 	{
-		LockGuard _(s_process_lock);
+		SpinLockGuard _(s_process_lock);
 
 		for (auto* process : s_processes)
 		{
@@ -46,9 +45,9 @@ namespace Kernel
 		}
 	}
 
-	void Process::for_each_process_in_session(pid_t sid, const BAN::Function<BAN::Iteration(Process&)>& callback)
+	static void for_each_process_in_session(pid_t sid, const BAN::Function<BAN::Iteration(Process&)>& callback)
 	{
-		LockGuard _(s_process_lock);
+		SpinLockGuard _(s_process_lock);
 
 		for (auto* process : s_processes)
 		{
@@ -90,9 +89,10 @@ namespace Kernel
 
 	void Process::register_to_scheduler()
 	{
-		s_process_lock.lock();
+		{
+			SpinLockGuard _(s_process_lock);
 			MUST(s_processes.push_back(this));
-		s_process_lock.unlock();
+		}
 		for (auto* thread : m_threads)
 			MUST(Scheduler::get().add_thread(thread));
 	}
@@ -138,8 +138,6 @@ namespace Kernel
 
 		char** argv = nullptr;
 		{
-			PageTableScope _(process->page_table());
-
 			size_t needed_bytes = sizeof(char*) * 2 + path.size() + 1;
 			if (auto rem = needed_bytes % PAGE_SIZE)
 				needed_bytes += PAGE_SIZE - rem;
@@ -196,14 +194,14 @@ namespace Kernel
 
 	void Process::add_thread(Thread* thread)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		MUST(m_threads.push_back(thread));
 	}
 
 	void Process::cleanup_function()
 	{
 		{
-			LockGuard _(s_process_lock);
+			SpinLockGuard _(s_process_lock);
 			for (size_t i = 0; i < s_processes.size(); i++)
 				if (s_processes[i] == this)
 					s_processes.remove(i);
@@ -217,7 +215,7 @@ namespace Kernel
 		while (m_exit_status.waiting > 0)
 			Scheduler::get().reschedule();
 
-		m_lock.lock();
+		m_process_lock.lock();
 
 		m_open_file_descriptors.close_all();
 
@@ -256,7 +254,7 @@ namespace Kernel
 
 	void Process::exit(int status, int signal)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		m_exit_status.exit_code = __WGENEXITCODE(status, signal);
 		for (auto* thread : m_threads)
 			if (thread != &Thread::current())
@@ -277,7 +275,7 @@ namespace Kernel
 		meminfo.phys_pages = 0;
 
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			for (auto* thread : m_threads)
 			{
 				meminfo.virt_pages += thread->virtual_page_count();
@@ -326,13 +324,13 @@ namespace Kernel
 
 	size_t Process::proc_cmdline(off_t offset, BAN::ByteSpan buffer) const
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		return read_from_vec_of_str(m_cmdline, offset, buffer);
 	}
 
 	size_t Process::proc_environ(off_t offset, BAN::ByteSpan buffer) const
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		return read_from_vec_of_str(m_environ, offset, buffer);
 	}
 
@@ -345,7 +343,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_gettermios(::termios* termios)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		TRY(validate_pointer_access(termios, sizeof(::termios)));
 
@@ -364,7 +362,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_settermios(const ::termios* termios)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		TRY(validate_pointer_access(termios, sizeof(::termios)));
 
@@ -403,7 +401,7 @@ namespace Kernel
 	{
 		auto page_table = BAN::UniqPtr<PageTable>::adopt(TRY(PageTable::create_userspace()));
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		BAN::String working_directory;
 		TRY(working_directory.append(m_working_directory));
@@ -443,7 +441,7 @@ namespace Kernel
 	{
 		// NOTE: We scope everything for automatic deletion
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 
 			TRY(validate_string_access(path));
 			auto loadable_elf = TRY(load_elf_for_exec(m_credentials, path, m_working_directory, page_table()));
@@ -579,7 +577,7 @@ namespace Kernel
 	BAN::ErrorOr<long> Process::sys_wait(pid_t pid, int* stat_loc, int options)
 	{
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			TRY(validate_pointer_access(stat_loc, sizeof(int)));
 		}
 
@@ -612,7 +610,7 @@ namespace Kernel
 	BAN::ErrorOr<long> Process::sys_nanosleep(const timespec* rqtp, timespec* rmtp)
 	{
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			TRY(validate_pointer_access(rqtp, sizeof(timespec)));
 			if (rmtp)
 				TRY(validate_pointer_access(rmtp, sizeof(timespec)));
@@ -654,7 +652,7 @@ namespace Kernel
 				return BAN::Error::from_errno(ENOTSUP);
 		}
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		auto absolute_path = TRY(absolute_path_of(path));
 
@@ -683,7 +681,7 @@ namespace Kernel
 	{
 		ASSERT(&Process::current() == this);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		if (Thread::current().stack().contains(address))
 		{
@@ -711,13 +709,13 @@ namespace Kernel
 	BAN::ErrorOr<long> Process::open_inode(BAN::RefPtr<Inode> inode, int flags)
 	{
 		ASSERT(inode);
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		return TRY(m_open_file_descriptors.open(inode, flags));
 	}
 
 	BAN::ErrorOr<long> Process::open_file(BAN::StringView path, int flags, mode_t mode)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		BAN::String absolute_path = TRY(absolute_path_of(path));
 
@@ -750,14 +748,14 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_open(const char* path, int flags, mode_t mode)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 		return open_file(path, flags, mode);
 	}
 
 	BAN::ErrorOr<long> Process::sys_openat(int fd, const char* path, int flags, mode_t mode)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		TRY(validate_string_access(path));
 
@@ -773,28 +771,28 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_close(int fd)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(m_open_file_descriptors.close(fd));
 		return 0;
 	}
 
 	BAN::ErrorOr<long> Process::sys_read(int fd, void* buffer, size_t count)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(buffer, count));
 		return TRY(m_open_file_descriptors.read(fd, BAN::ByteSpan((uint8_t*)buffer, count)));
 	}
 
 	BAN::ErrorOr<long> Process::sys_write(int fd, const void* buffer, size_t count)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(buffer, count));
 		return TRY(m_open_file_descriptors.write(fd, BAN::ByteSpan((uint8_t*)buffer, count)));
 	}
 
 	BAN::ErrorOr<long> Process::sys_create(const char* path, mode_t mode)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 		TRY(create_file_or_dir(path, mode));
 		return 0;
@@ -802,7 +800,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_create_dir(const char* path, mode_t mode)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 		BAN::StringView path_sv(path);
 		if (!path_sv.empty() && path_sv.back() == '/')
@@ -813,7 +811,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_unlink(const char* path)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 
 		auto absolute_path = TRY(absolute_path_of(path));
@@ -846,7 +844,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_readlink(const char* path, char* buffer, size_t bufsize)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 		TRY(validate_pointer_access(buffer, bufsize));
 
@@ -857,7 +855,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_readlinkat(int fd, const char* path, char* buffer, size_t bufsize)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 		TRY(validate_pointer_access(buffer, bufsize));
 
@@ -874,7 +872,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_pread(int fd, void* buffer, size_t count, off_t offset)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(buffer, count));
 		auto inode = TRY(m_open_file_descriptors.inode_of(fd));
 		return TRY(inode->read(offset, { (uint8_t*)buffer, count }));
@@ -885,7 +883,7 @@ namespace Kernel
 		if (mode & S_IFMASK)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 
 		auto absolute_path = TRY(absolute_path_of(path));
@@ -897,7 +895,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_chown(const char* path, uid_t uid, gid_t gid)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 
 		auto absolute_path = TRY(absolute_path_of(path));
@@ -909,7 +907,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_socket(int domain, int type, int protocol)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		return TRY(m_open_file_descriptors.socket(domain, type, protocol));
 	}
 
@@ -920,7 +918,7 @@ namespace Kernel
 		if (!address && address_len)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		if (address)
 		{
 			TRY(validate_pointer_access(address_len, sizeof(*address_len)));
@@ -936,7 +934,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_bind(int socket, const sockaddr* address, socklen_t address_len)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(address, address_len));
 
 		auto inode = TRY(m_open_file_descriptors.inode_of(socket));
@@ -949,7 +947,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_connect(int socket, const sockaddr* address, socklen_t address_len)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(address, address_len));
 
 		auto inode = TRY(m_open_file_descriptors.inode_of(socket));
@@ -962,7 +960,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_listen(int socket, int backlog)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		auto inode = TRY(m_open_file_descriptors.inode_of(socket));
 		if (!inode->mode().ifsock())
@@ -974,7 +972,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_sendto(const sys_sendto_t* arguments)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(arguments, sizeof(sys_sendto_t)));
 		TRY(validate_pointer_access(arguments->message, arguments->length));
 		TRY(validate_pointer_access(arguments->dest_addr, arguments->dest_len));
@@ -994,7 +992,7 @@ namespace Kernel
 		if (!arguments->address && arguments->address_len)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(arguments, sizeof(sys_recvfrom_t)));
 		TRY(validate_pointer_access(arguments->buffer, arguments->length));
 		if (arguments->address)
@@ -1013,14 +1011,14 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_ioctl(int fildes, int request, void* arg)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		auto inode = TRY(m_open_file_descriptors.inode_of(fildes));
 		return TRY(inode->ioctl(request, arg));
 	}
 
 	BAN::ErrorOr<long> Process::sys_pselect(sys_pselect_t* arguments)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		TRY(validate_pointer_access(arguments, sizeof(sys_pselect_t)));
 		if (arguments->readfds)
@@ -1089,7 +1087,7 @@ namespace Kernel
 			if (set_bits > 0)
 				break;
 
-			LockFreeGuard free(m_lock);
+			LockFreeGuard free(m_process_lock);
 			SystemTimer::get().sleep(1);
 		}
 
@@ -1115,7 +1113,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_pipe(int fildes[2])
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(fildes, sizeof(int) * 2));
 		TRY(m_open_file_descriptors.pipe(fildes));
 		return 0;
@@ -1123,32 +1121,32 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_dup(int fildes)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		return TRY(m_open_file_descriptors.dup(fildes));
 	}
 
 	BAN::ErrorOr<long> Process::sys_dup2(int fildes, int fildes2)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		return TRY(m_open_file_descriptors.dup2(fildes, fildes2));
 	}
 
 	BAN::ErrorOr<long> Process::sys_fcntl(int fildes, int cmd, int extra)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		return TRY(m_open_file_descriptors.fcntl(fildes, cmd, extra));
 	}
 
 	BAN::ErrorOr<long> Process::sys_seek(int fd, off_t offset, int whence)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(m_open_file_descriptors.seek(fd, offset, whence));
 		return 0;
 	}
 
 	BAN::ErrorOr<long> Process::sys_tell(int fd)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		return TRY(m_open_file_descriptors.tell(fd));
 	}
 
@@ -1156,7 +1154,7 @@ namespace Kernel
 	{
 		BAN::String absolute_source, absolute_target;
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			TRY(absolute_source.append(TRY(absolute_path_of(source))));
 			TRY(absolute_target.append(TRY(absolute_path_of(target))));
 		}
@@ -1166,7 +1164,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_fstat(int fd, struct stat* buf)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(buf, sizeof(struct stat)));
 		TRY(m_open_file_descriptors.fstat(fd, buf));
 		return 0;
@@ -1174,7 +1172,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_fstatat(int fd, const char* path, struct stat* buf, int flag)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(buf, sizeof(struct stat)));
 		TRY(m_open_file_descriptors.fstatat(fd, path, buf, flag));
 		return 0;
@@ -1182,7 +1180,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_stat(const char* path, struct stat* buf, int flag)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(buf, sizeof(struct stat)));
 		TRY(m_open_file_descriptors.stat(TRY(absolute_path_of(path)), buf, flag));
 		return 0;
@@ -1235,7 +1233,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_readdir(int fd, DirectoryEntryList* list, size_t list_size)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_pointer_access(list, list_size));
 		TRY(m_open_file_descriptors.read_dir_entries(fd, list, list_size));
 		return 0;
@@ -1246,7 +1244,7 @@ namespace Kernel
 		BAN::String absolute_path;
 
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			TRY(validate_string_access(path));
 			absolute_path = TRY(absolute_path_of(path));
 		}
@@ -1255,7 +1253,7 @@ namespace Kernel
 		if (!file.inode->mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		m_working_directory = BAN::move(file.canonical_path);
 
 		return 0;
@@ -1263,7 +1261,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_getpwd(char* buffer, size_t size)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		TRY(validate_pointer_access(buffer, size));
 
@@ -1279,7 +1277,7 @@ namespace Kernel
 	BAN::ErrorOr<long> Process::sys_mmap(const sys_mmap_t* args)
 	{
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			TRY(validate_pointer_access(args, sizeof(sys_mmap_t)));
 		}
 
@@ -1320,7 +1318,7 @@ namespace Kernel
 				region_type, page_flags
 			));
 
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			TRY(m_mapped_regions.push_back(BAN::move(region)));
 			return m_mapped_regions.back()->vaddr();
 		}
@@ -1328,7 +1326,7 @@ namespace Kernel
 		if (args->addr != nullptr)
 			return BAN::Error::from_errno(ENOTSUP);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		auto inode = TRY(m_open_file_descriptors.inode_of(args->fildes));
 
@@ -1376,7 +1374,7 @@ namespace Kernel
 		if (vaddr % PAGE_SIZE != 0)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		// FIXME: We should only map partial regions
 		for (size_t i = 0; i < m_mapped_regions.size(); i++)
@@ -1395,7 +1393,7 @@ namespace Kernel
 		if (vaddr % PAGE_SIZE != 0)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		for (auto& mapped_region : m_mapped_regions)
 			if (mapped_region->overlaps(vaddr, len))
@@ -1406,7 +1404,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_tty_ctrl(int fildes, int command, int flags)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		auto inode = TRY(m_open_file_descriptors.inode_of(fildes));
 		if (!inode->is_tty())
@@ -1419,7 +1417,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_termid(char* buffer)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		TRY(validate_string_access(buffer));
 
@@ -1440,7 +1438,7 @@ namespace Kernel
 	BAN::ErrorOr<long> Process::sys_clock_gettime(clockid_t clock_id, timespec* tp)
 	{
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			TRY(validate_pointer_access(tp, sizeof(timespec)));
 		}
 
@@ -1465,7 +1463,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_load_keymap(const char* path)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 		TRY(validate_string_access(path));
 
 		if (!m_credentials.is_superuser())
@@ -1482,7 +1480,7 @@ namespace Kernel
 			return BAN::Error::from_errno(EINVAL);
 
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_process_lock);
 			TRY(validate_pointer_access((void*)handler, sizeof(handler)));
 		}
 
@@ -1532,7 +1530,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_tcsetpgrp(int fd, pid_t pgrp)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		if (!m_controlling_terminal)
 			return BAN::Error::from_errno(ENOTTY);
@@ -1568,7 +1566,7 @@ namespace Kernel
 		if (uid < 0 || uid >= 1'000'000'000)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		// If the process has appropriate privileges, setuid() shall set the real user ID, effective user ID, and the saved
 		// set-user-ID of the calling process to uid.
@@ -1598,7 +1596,7 @@ namespace Kernel
 		if (gid < 0 || gid >= 1'000'000'000)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		// If the process has appropriate privileges, setgid() shall set the real group ID, effective group ID, and the saved
 		// set-group-ID of the calling process to gid.
@@ -1626,7 +1624,7 @@ namespace Kernel
 		if (uid < 0 || uid >= 1'000'000'000)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		// If uid is equal to the real user ID or the saved set-user-ID, or if the process has appropriate privileges, seteuid()
 		// shall set the effective user ID of the calling process to uid; the real user ID and saved set-user-ID shall remain unchanged.
@@ -1645,7 +1643,7 @@ namespace Kernel
 		if (gid < 0 || gid >= 1'000'000'000)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		// If gid is equal to the real group ID or the saved set-group-ID, or if the process has appropriate privileges, setegid()
 		// shall set the effective group ID of the calling process to gid; the real group ID, saved set-group-ID, and any
@@ -1673,7 +1671,7 @@ namespace Kernel
 		// by the ruid and euid arguments. If ruid or euid is -1, the corresponding effective or real user ID of the current
 		// process shall be left unchanged.
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		// A process with appropriate privileges can set either ID to any value.
 		if (!m_credentials.is_superuser())
@@ -1721,7 +1719,7 @@ namespace Kernel
 
 		// The real and effective group IDs may be set to different values in the same call.
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		// Only a process with appropriate privileges can set the real group ID and the effective group ID to any valid value.
 		if (!m_credentials.is_superuser())
@@ -1754,7 +1752,7 @@ namespace Kernel
 		if (pgid < 0)
 			return BAN::Error::from_errno(EINVAL);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		if (pid == 0)
 			pid = m_pid;
@@ -1819,7 +1817,7 @@ namespace Kernel
 
 	BAN::ErrorOr<long> Process::sys_getpgid(pid_t pid)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		if (pid == 0 || pid == m_pid)
 			return m_pgrp;
@@ -1851,7 +1849,7 @@ namespace Kernel
 
 	BAN::ErrorOr<BAN::String> Process::absolute_path_of(BAN::StringView path) const
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_process_lock);
 
 		if (path.empty() || path == "."sv)
 			return m_working_directory;

kernel/kernel/Scheduler.cpp

@@ -35,9 +35,10 @@ namespace Kernel
 	BAN::ErrorOr<void> Scheduler::initialize()
 	{
 		ASSERT(s_instance == nullptr);
-		s_instance = new Scheduler();
+		Scheduler* scheduler = new Scheduler();
-		ASSERT(s_instance);
+		ASSERT(scheduler);
-		s_instance->m_idle_thread = TRY(Thread::create_kernel([](void*) { for (;;) asm volatile("hlt"); }, nullptr, nullptr));
+		scheduler->m_idle_thread = TRY(Thread::create_kernel([](void*) { for (;;) asm volatile("hlt"); }, nullptr, nullptr));
+		s_instance = scheduler;
 		return {};
 	}
 

kernel/kernel/SpinLock.cpp

@@ -1,86 +0,0 @@
-#include <kernel/Scheduler.h>
-#include <kernel/SpinLock.h>
-
-namespace Kernel
-{
-
-	void SpinLock::lock()
-	{
-		pid_t tid = Scheduler::current_tid();
-		ASSERT(tid != m_locker);
-		while (!m_locker.compare_exchange(-1, tid))
-			Scheduler::get().reschedule();
-	}
-
-	void SpinLock::unlock()
-	{
-		ASSERT(m_locker == Scheduler::current_tid());
-		m_locker = -1;
-	}
-
-	bool SpinLock::is_locked() const
-	{
-		return m_locker != -1;
-	}
-
-	void RecursiveSpinLock::lock()
-	{
-		pid_t tid = Scheduler::current_tid();
-		if (m_locker != tid)
-		{
-			while (!m_locker.compare_exchange(-1, tid))
-				Scheduler::get().reschedule();
-			ASSERT(m_lock_depth == 0);
-		}
-		m_lock_depth++;
-	}
-
-	void RecursiveSpinLock::unlock()
-	{
-		ASSERT(m_lock_depth > 0);
-		ASSERT(m_locker == Scheduler::current_tid());
-		if (--m_lock_depth == 0)
-			m_locker = -1;
-	}
-
-	bool RecursiveSpinLock::is_locked() const
-	{
-		return m_locker != -1;
-	}
-
-	void RecursivePrioritySpinLock::lock()
-	{
-		pid_t tid = Scheduler::current_tid();
-
-		bool has_priority = !Thread::current().is_userspace();
-		if (has_priority)
-			m_queue_length++;
-
-		if (m_locker != tid)
-		{
-			while (!((has_priority || m_queue_length == 0) && m_locker.compare_exchange(-1, tid)))
-				Scheduler::get().reschedule();
-			ASSERT(m_lock_depth == 0);
-		}
-		m_lock_depth++;
-	}
-
-	void RecursivePrioritySpinLock::unlock()
-	{
-		ASSERT(m_lock_depth > 0);
-		ASSERT(m_locker == Scheduler::current_tid());
-
-		bool has_priority = !Thread::current().is_userspace();
-		if (has_priority)
-			m_queue_length--;
-
-		if (--m_lock_depth == 0)
-			m_locker = -1;
-	}
-
-	bool RecursivePrioritySpinLock::is_locked() const
-	{
-		return m_locker != -1;
-	}
-
-}

kernel/kernel/Storage/ATA/ATABus.cpp

@@ -2,7 +2,7 @@
 #include <kernel/IDT.h>
 #include <kernel/InterruptController.h>
 #include <kernel/IO.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Storage/ATA/ATABus.h>
 #include <kernel/Storage/ATA/ATADefinitions.h>
 #include <kernel/Storage/ATA/ATADevice.h>
@@ -261,7 +261,7 @@ namespace Kernel
 		if (lba + sector_count > device.sector_count())
 			return BAN::Error::from_error_code(ErrorCode::Storage_Boundaries);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (lba < (1 << 28))
 		{
@@ -298,7 +298,7 @@ namespace Kernel
 		if (lba + sector_count > device.sector_count())
 			return BAN::Error::from_error_code(ErrorCode::Storage_Boundaries);
 
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (lba < (1 << 28))
 		{

kernel/kernel/Storage/DiskCache.cpp

@@ -1,5 +1,5 @@
 #include <kernel/CriticalScope.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/PageTable.h>
 #include <kernel/Storage/DiskCache.h>
@@ -32,10 +32,6 @@ namespace Kernel
 		uint64_t page_cache_offset = sector % sectors_per_page;
 		uint64_t page_cache_start = sector - page_cache_offset;
 
-		PageTable& page_table = PageTable::current();
-		LockGuard page_table_locker(page_table);
-		ASSERT(page_table.is_page_free(0));
-
 		for (auto& cache : m_cache)
 		{
 			if (cache.first_sector < page_cache_start)
@@ -46,10 +42,9 @@ namespace Kernel
 			if (!(cache.sector_mask & (1 << page_cache_offset)))
 				continue;
 
-			CriticalScope _;
+			PageTable::with_fast_page(cache.paddr, [&] {
-			PageTable::map_fast_page(cache.paddr);
 				memcpy(buffer.data(), PageTable::fast_page_as_ptr(page_cache_offset * m_sector_size), m_sector_size);
-			PageTable::unmap_fast_page();
+			});
 
 			return true;
 		}
@@ -64,10 +59,6 @@ namespace Kernel
 		uint64_t page_cache_offset = sector % sectors_per_page;
 		uint64_t page_cache_start = sector - page_cache_offset;
 
-		PageTable& page_table = PageTable::current();
-		LockGuard page_table_locker(page_table);
-		ASSERT(page_table.is_page_free(0));
-
 		size_t index = 0;
 
 		// Search the cache if the have this sector in memory
@@ -80,12 +71,9 @@ namespace Kernel
 			if (cache.first_sector > page_cache_start)
 				break;
 
-			{
+			PageTable::with_fast_page(cache.paddr, [&] {
-				CriticalScope _;
-				PageTable::map_fast_page(cache.paddr);
 				memcpy(PageTable::fast_page_as_ptr(page_cache_offset * m_sector_size), buffer.data(), m_sector_size);
-				PageTable::unmap_fast_page();
+			});
-			}
 
 			cache.sector_mask |= 1 << page_cache_offset;
 			if (dirty)
@@ -111,12 +99,9 @@ namespace Kernel
 			return ret.error();
 		}
 
-		{
+		PageTable::with_fast_page(cache.paddr, [&] {
-			CriticalScope _;
-			PageTable::map_fast_page(cache.paddr);
 			memcpy(PageTable::fast_page_as_ptr(page_cache_offset * m_sector_size), buffer.data(), m_sector_size);
-			PageTable::unmap_fast_page();
+		});
-		}
 
 		return {};
 	}
@@ -128,12 +113,9 @@ namespace Kernel
 			if (cache.dirty_mask == 0)
 				continue;
 
-			{
+			PageTable::with_fast_page(cache.paddr, [&] {
-				CriticalScope _;
-				PageTable::map_fast_page(cache.paddr);
 				memcpy(m_sync_cache.data(), PageTable::fast_page_as_ptr(), PAGE_SIZE);
-				PageTable::unmap_fast_page();
+			});
-			}
 
 			uint8_t sector_start = 0;
 			uint8_t sector_count = 0;

kernel/kernel/Storage/NVMe/Queue.cpp

@@ -1,4 +1,4 @@
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Scheduler.h>
 #include <kernel/Storage/NVMe/Queue.h>
 #include <kernel/Timer/Timer.h>
@@ -44,7 +44,7 @@ namespace Kernel
 
 	uint16_t NVMeQueue::submit_command(NVMe::SubmissionQueueEntry& sqe)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		ASSERT(m_done == false);
 		m_status = 0;

kernel/kernel/Storage/StorageDevice.cpp

@@ -4,7 +4,7 @@
 #include <BAN/UTF8.h>
 #include <kernel/FS/DevFS/FileSystem.h>
 #include <kernel/FS/VirtualFileSystem.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/PCI.h>
 #include <kernel/Storage/StorageDevice.h>
 #include <kernel/Thread.h>
@@ -150,7 +150,7 @@ namespace Kernel
 		BAN::Vector<uint8_t> lba1;
 		TRY(lba1.resize(sector_size()));
 
-		TRY(read_sectors(1, 1, lba1.span()));
+		TRY(read_sectors(1, 1, BAN::ByteSpan { lba1.span() }));
 
 		const GPTHeader& header = *(const GPTHeader*)lba1.data();
 		if (!is_valid_gpt_header(header, sector_size()))
@@ -165,7 +165,7 @@ namespace Kernel
 
 		BAN::Vector<uint8_t> entry_array;
 		TRY(entry_array.resize(size));
-		TRY(read_sectors(header.partition_entry_lba, size / sector_size(), entry_array.span()));
+		TRY(read_sectors(header.partition_entry_lba, size / sector_size(), BAN::ByteSpan { entry_array.span() }));
 
 		if (!is_valid_gpt_crc32(header, lba1, entry_array))
 			return BAN::Error::from_error_code(ErrorCode::Storage_GPTHeader);
@@ -207,14 +207,14 @@ namespace Kernel
 
 	void StorageDevice::add_disk_cache()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		ASSERT(!m_disk_cache.has_value());
 		m_disk_cache.emplace(sector_size(), *this);
 	}
 
 	BAN::ErrorOr<void> StorageDevice::sync_disk_cache()
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 		if (m_disk_cache.has_value())
 			TRY(m_disk_cache->sync());
 		return {};
@@ -225,14 +225,14 @@ namespace Kernel
 		ASSERT(buffer.size() >= sector_count * sector_size());
 
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_mutex);
 			if (!m_disk_cache.has_value())
 				return read_sectors_impl(lba, sector_count, buffer);
 		}
 
 		for (uint64_t offset = 0; offset < sector_count; offset++)
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_mutex);
 			auto sector_buffer = buffer.slice(offset * sector_size(), sector_size());
 			if (m_disk_cache->read_from_cache(lba + offset, sector_buffer))
 				continue;
@@ -248,14 +248,14 @@ namespace Kernel
 		ASSERT(buffer.size() >= sector_count * sector_size());
 
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_mutex);
 			if (!m_disk_cache.has_value())
 				return write_sectors_impl(lba, sector_count, buffer);
 		}
 
 		for (uint8_t offset = 0; offset < sector_count; offset++)
 		{
-			LockGuard _(m_lock);
+			LockGuard _(m_mutex);
 			auto sector_buffer = buffer.slice(offset * sector_size(), sector_size());
 			if (m_disk_cache->write_to_cache(lba + offset, sector_buffer, true).is_error())
 				TRY(write_sectors_impl(lba + offset, 1, sector_buffer));

kernel/kernel/Terminal/TTY.cpp

@@ -4,7 +4,7 @@
 #include <kernel/Debug.h>
 #include <kernel/FS/DevFS/FileSystem.h>
 #include <kernel/FS/VirtualFileSystem.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Process.h>
 #include <kernel/Terminal/TTY.h>
 
@@ -122,7 +122,7 @@ namespace Kernel
 
 	void TTY::on_key_event(Input::KeyEvent event)
 	{
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		if (event.released())
 			return;
@@ -205,7 +205,7 @@ namespace Kernel
 		if (ch == 0)
 			return;
 
-		LockGuard _(m_lock);
+		LockGuard _(m_mutex);
 
 		// ^C
 		if (ch == '\x03')
@@ -310,24 +310,17 @@ namespace Kernel
 
 	void TTY::putchar(uint8_t ch)
 	{
+		SpinLockGuard _(m_write_lock);
 		if (m_tty_ctrl.draw_graphics)
 			putchar_impl(ch);
 	}
 
 	BAN::ErrorOr<size_t> TTY::read_impl(off_t, BAN::ByteSpan buffer)
 	{
-		LockGuard _(m_lock);
 		while (!m_output.flush)
 		{
-			// FIXME: this is very hacky way to unlock lock temporarily
+			LockFreeGuard _(m_mutex);
-			uint32_t depth = m_lock.lock_depth();
+			TRY(Thread::current().block_or_eintr_indefinite(m_output.semaphore));
-			for (uint32_t i = 0; i < depth; i++)
-				m_lock.unlock();
-			auto eintr = Thread::current().block_or_eintr_indefinite(m_output.semaphore);
-			for (uint32_t i = 0; i < depth; i++)
-				m_lock.lock();
-			if (eintr.is_error())
-				return eintr.release_error();
 		}
 
 		if (m_output.bytes == 0)
@@ -352,7 +345,7 @@ namespace Kernel
 
 	BAN::ErrorOr<size_t> TTY::write_impl(off_t, BAN::ConstByteSpan buffer)
 	{
-		LockGuard _(m_lock);
+		SpinLockGuard _(m_write_lock);
 		for (size_t i = 0; i < buffer.size(); i++)
 			putchar(buffer[i]);
 		return buffer.size();
@@ -361,7 +354,7 @@ namespace Kernel
 	void TTY::putchar_current(uint8_t ch)
 	{
 		ASSERT(s_tty);
-		LockGuard _(s_tty->m_lock);
+		SpinLockGuard _(s_tty->m_write_lock);
 		s_tty->putchar(ch);
 	}
 

kernel/kernel/Terminal/VirtualTTY.cpp

@@ -4,7 +4,7 @@
 #include <kernel/Debug.h>
 #include <kernel/Device/DeviceNumbers.h>
 #include <kernel/FS/DevFS/FileSystem.h>
-#include <kernel/LockGuard.h>
+#include <kernel/Lock/LockGuard.h>
 #include <kernel/Process.h>
 #include <kernel/Terminal/VirtualTTY.h>
 
@@ -306,8 +306,6 @@ namespace Kernel
 
 	void VirtualTTY::putchar_impl(uint8_t ch)
 	{
-		ASSERT(m_lock.is_locked());
-
 		uint32_t codepoint = ch;
 
 		switch (m_state)

kernel/kernel/Thread.cpp

@@ -4,7 +4,6 @@
 #include <kernel/InterruptController.h>
 #include <kernel/InterruptStack.h>
 #include <kernel/Memory/kmalloc.h>
-#include <kernel/Memory/PageTableScope.h>
 #include <kernel/Process.h>
 #include <kernel/Scheduler.h>
 #include <kernel/Thread.h>