Kernel: Implement basic SpinLock

kernel/Makefile

@@ -45,6 +45,7 @@ kernel/PIT.o					\
 kernel/RTC.o					\
 kernel/Serial.o					\
 kernel/Shell.o					\
+kernel/SpinLock.o				\
 kernel/SSP.o					\
 kernel/TTY.o					\
 kernel/VesaTerminalDriver.o		\

kernel/arch/i386/SpinLock.S

@@ -0,0 +1,17 @@
+.global spinlock_lock_asm
+spinlock_lock_asm:
+	lock; btsl $0, (%edi)
+	jnc .done
+.retry:
+	pause
+	testl $1, (%edi)
+	jne .retry
+	lock; btsl $0, (%edi)
+	jc .retry
+.done:
+	ret
+
+.global spinlock_unlock_asm
+spinlock_unlock_asm:
+	movl $0, (%edi)
+	ret

kernel/arch/i386/make.config

@@ -7,4 +7,5 @@ KERNEL_ARCH_OBJS=		\
 $(ARCHDIR)/boot.o		\
 $(ARCHDIR)/IDT.o		\
 $(ARCHDIR)/MMU.o		\
+$(ARCHDIR)/SpinLock.o	\
  

kernel/arch/x86_64/SpinLock.S

@@ -0,0 +1,17 @@
+.global spinlock_lock_asm
+spinlock_lock_asm:
+	lock; btsq $0, (%rdi)
+	jnc .done
+.retry:
+	pause
+	testq $1, (%rdi)
+	jne .retry
+	lock; btsq $0, (%rdi)
+	jc .retry
+.done:
+	ret
+
+.global spinlock_unlock_asm
+spinlock_unlock_asm:
+	movq $0, (%rdi)
+	ret

kernel/arch/x86_64/make.config

@@ -6,6 +6,7 @@ KERNEL_ARCH_LIBS=
 KERNEL_ARCH_OBJS=		\
 $(ARCHDIR)/boot.o		\
 $(ARCHDIR)/IDT.o		\
-$(ARCHDIR)/MMU.o		\
 $(ARCHDIR)/interrupts.o	\
+$(ARCHDIR)/MMU.o		\
+$(ARCHDIR)/SpinLock.o	\
  

kernel/include/kernel/LockGuard.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <BAN/NoCopyMove.h>
+
+namespace Kernel
+{
+
+	template<typename Lock>
+	class LockGuard
+	{
+		BAN_NON_COPYABLE(LockGuard<Lock>);
+		BAN_NON_MOVABLE(LockGuard<Lock>);
+
+	public:
+		LockGuard(Lock& lock)
+			: m_lock(lock)
+		{
+			m_lock.lock();	
+		}
+
+		~LockGuard()
+		{
+			m_lock.unlock();
+		}
+	
+	private:
+		Lock& m_lock;
+	};
+
+}

kernel/include/kernel/SpinLock.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <BAN/NoCopyMove.h>
+
+namespace Kernel
+{
+
+	class SpinLock
+	{
+		BAN_NON_COPYABLE(SpinLock);
+		BAN_NON_MOVABLE(SpinLock);
+
+	public:
+		SpinLock() = default;
+		void lock();
+		void unlock();
+	
+	private:
+		int m_lock = 0;
+	};
+
+}

kernel/kernel/SpinLock.cpp

@@ -0,0 +1,19 @@
+#include <kernel/SpinLock.h>
+
+namespace Kernel
+{
+
+	extern "C" void spinlock_lock_asm(int*);
+	extern "C" void spinlock_unlock_asm(int*);
+
+	void SpinLock::lock()
+	{
+		spinlock_lock_asm(&m_lock);
+	}
+
+	void SpinLock::unlock()
+	{
+		spinlock_unlock_asm(&m_lock);
+	}
+
+}