CMakeLists.txt

@@ -8,7 +8,6 @@ endif()
 
 set(TOOLCHAIN_PREFIX ${CMAKE_SOURCE_DIR}/toolchain/local)
 
-if(EXISTS ${TOOLCHAIN_PREFIX}/bin/${BANAN_ARCH}-banan_os-g++)
 set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED True)
 set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}/bin/${BANAN_ARCH}-banan_os-g++)
@@ -16,6 +15,9 @@ if(EXISTS ${TOOLCHAIN_PREFIX}/bin/${BANAN_ARCH}-banan_os-g++)
 
 set(CMAKE_C_COMPILER ${TOOLCHAIN_PREFIX}/bin/${BANAN_ARCH}-banan_os-gcc)
 set(CMAKE_C_COMPILER_WORKS True)
+
+if(NOT EXISTS ${CMAKE_CXX_COMPILER})
+	set(CMAKE_CXX_COMPILER g++)
 endif()
 
 if(DEFINED QEMU_ACCEL)

kernel/CMakeLists.txt

@@ -194,10 +194,10 @@ add_custom_command(
 	COMMAND cp ${CRTEND} .
 )
 
-#add_custom_command(
+add_custom_command(
-#	TARGET kernel POST_BUILD
+	TARGET kernel POST_BUILD
-#	COMMAND x86_64-banan_os-strip ${CMAKE_CURRENT_BINARY_DIR}/kernel
+	COMMAND x86_64-banan_os-strip ${CMAKE_CURRENT_BINARY_DIR}/kernel
-#)
+)
 
 add_custom_command(
 	OUTPUT font/prefs.psf.o

kernel/arch/x86_64/IDT.cpp

@@ -13,7 +13,7 @@
 #define REGISTER_ISR_HANDLER(i) register_interrupt_handler(i, isr ## i)
 #define REGISTER_IRQ_HANDLER(i) register_interrupt_handler(IRQ_VECTOR_BASE + i, irq ## i)
 
-namespace Kernel::IDT
+namespace IDT
 {
 
 	struct Registers
@@ -63,7 +63,7 @@ namespace Kernel::IDT
 	static IDTR				s_idtr;
 	static GateDescriptor*	s_idt = nullptr;
 
-	static Interruptable* s_interruptables[0x10] {};
+	static void(*s_irq_handlers[0x10])() { nullptr };
 
 	enum ISR
 	{
@@ -160,62 +160,53 @@ namespace Kernel::IDT
 		"Unkown Exception 0x1F",
 	};
 
-	extern "C" void cpp_isr_handler(uint64_t isr, uint64_t error, InterruptStack& interrupt_stack, const Registers* regs)
+	extern "C" void cpp_isr_handler(uint64_t isr, uint64_t error, Kernel::InterruptStack& interrupt_stack, const Registers* regs)
 	{
 #if __enable_sse
 		bool from_userspace = (interrupt_stack.cs & 0b11) == 0b11;
 		if (from_userspace)
-			Thread::current().save_sse();
+			Kernel::Thread::current().save_sse();
 #endif
 
-		pid_t tid = Scheduler::current_tid();
+		pid_t tid = Kernel::Scheduler::current_tid();
-		pid_t pid = tid ? Process::current().pid() : 0;
+		pid_t pid = tid ? Kernel::Process::current().pid() : 0;
 
-		if (tid)
+		if (pid && isr == ISR::PageFault)
 		{
-			Thread::current().set_return_rsp(interrupt_stack.rsp);
-			Thread::current().set_return_rip(interrupt_stack.rip);
-
-			if (isr == ISR::PageFault)
-			{
-				// Check if stack is OOB
-				auto& stack = Thread::current().stack();
-				if (interrupt_stack.rsp < stack.vaddr())
-				{
-					derrorln("Stack overflow");
-					goto done;
-				}
-				if (interrupt_stack.rsp >= stack.vaddr() + stack.size())
-				{
-					derrorln("Stack underflow");
-					goto done;
-				}
-
-				// Try demand paging on non present pages
 			PageFaultError page_fault_error;
 			page_fault_error.raw = error;
+
+			// Try demand paging on non present pages
 			if (!page_fault_error.present)
 			{
 				asm volatile("sti");
-					auto result = Process::current().allocate_page_for_demand_paging(regs->cr2);
+				auto result = Kernel::Process::current().allocate_page_for_demand_paging(regs->cr2);
 				asm volatile("cli");
 
 				if (!result.is_error() && result.value())
-						goto done;
+					return;
 
 				if (result.is_error())
 				{
 					dwarnln("Demand paging: {}", result.error());
-						Thread::current().handle_signal(SIGTERM);
+					Kernel::Thread::current().handle_signal(SIGTERM);
-						goto done;
-					}
 				}
 			}
 		}
 
-		if (PageTable::current().get_page_flags(interrupt_stack.rip & PAGE_ADDR_MASK) & PageTable::Flags::Present)
+		if (tid)
 		{
-			auto* machine_code = (const uint8_t*)interrupt_stack.rip;
+			auto start = Kernel::Thread::current().stack_base();
+			auto end = start + Kernel::Thread::current().stack_size();
+			if (interrupt_stack.rsp < start)
+				derrorln("Stack overflow");
+			if (interrupt_stack.rsp >= end)
+				derrorln("Stack underflow");
+		}
+
+		if (Kernel::PageTable::current().get_page_flags(interrupt_stack.rip & PAGE_ADDR_MASK) & Kernel::PageTable::Flags::Present)
+		{
+			uint8_t* machine_code = (uint8_t*)interrupt_stack.rip;
 			dwarnln("While executing: {2H}{2H}{2H}{2H}{2H}{2H}{2H}{2H}",
 				machine_code[0],
 				machine_code[1],
@@ -242,10 +233,16 @@ namespace Kernel::IDT
 			regs->cr0, regs->cr2, regs->cr3, regs->cr4
 		);
 		if (isr == ISR::PageFault)
-			PageTable::current().debug_dump();
+			Kernel::PageTable::current().debug_dump();
 		Debug::dump_stack_trace();
 
-		if (tid && Thread::current().is_userspace())
+		if (tid)
+		{
+			Kernel::Thread::current().set_return_rsp(interrupt_stack.rsp);
+			Kernel::Thread::current().set_return_rip(interrupt_stack.rip);
+		}
+
+		if (tid && Kernel::Thread::current().is_userspace())
 		{
 			// TODO: Confirm and fix the exception to signal mappings
 
@@ -273,38 +270,36 @@ namespace Kernel::IDT
 				break;
 			}
 
-			Thread::current().handle_signal(signal);
+			Kernel::Thread::current().handle_signal(signal);
 		}
 		else
 		{
-			panic("Unhandled exception");
+			Kernel::panic("Unhandled exception");
 		}
 
-		ASSERT(Thread::current().state() != Thread::State::Terminated);
+		ASSERT(Kernel::Thread::current().state() != Kernel::Thread::State::Terminated);
 
-done:
 #if __enable_sse
 		if (from_userspace)
 		{
-			ASSERT(Thread::current().state() == Thread::State::Executing);
+			ASSERT(Kernel::Thread::current().state() == Kernel::Thread::State::Executing);
-			Thread::current().load_sse();
+			Kernel::Thread::current().load_sse();
 		}
 #endif
-		return;
 	}
 
-	extern "C" void cpp_irq_handler(uint64_t irq, InterruptStack& interrupt_stack)
+	extern "C" void cpp_irq_handler(uint64_t irq, Kernel::InterruptStack& interrupt_stack)
 	{
 #if __enable_sse
 		bool from_userspace = (interrupt_stack.cs & 0b11) == 0b11;
 		if (from_userspace)
-			Thread::current().save_sse();
+			Kernel::Thread::current().save_sse();
 #endif
 
-		if (Scheduler::current_tid())
+		if (Kernel::Scheduler::current_tid())
 		{
-			Thread::current().set_return_rsp(interrupt_stack.rsp);
+			Kernel::Thread::current().set_return_rsp(interrupt_stack.rsp);
-			Thread::current().set_return_rip(interrupt_stack.rip);
+			Kernel::Thread::current().set_return_rip(interrupt_stack.rip);
 		}
 
 		if (!InterruptController::get().is_in_service(irq))
@@ -312,21 +307,21 @@ done:
 		else
 		{
 			InterruptController::get().eoi(irq);
-			if (s_interruptables[irq])
+			if (s_irq_handlers[irq])
-				s_interruptables[irq]->handle_irq();
+				s_irq_handlers[irq]();
 			else
 				dprintln("no handler for irq 0x{2H}\n", irq);
 		}
 
-		Scheduler::get().reschedule_if_idling();
+		Kernel::Scheduler::get().reschedule_if_idling();
 
-		ASSERT(Thread::current().state() != Thread::State::Terminated);
+		ASSERT(Kernel::Thread::current().state() != Kernel::Thread::State::Terminated);
 
 #if __enable_sse
 		if (from_userspace)
 		{
-			ASSERT(Thread::current().state() == Thread::State::Executing);
+			ASSERT(Kernel::Thread::current().state() == Kernel::Thread::State::Executing);
-			Thread::current().load_sse();
+			Kernel::Thread::current().load_sse();
 		}
 #endif
 	}
@@ -354,9 +349,9 @@ done:
 		s_idt[index].flags = 0xEE;
 	}
 
-	void register_irq_handler(uint8_t irq, Interruptable* interruptable)
+	void register_irq_handler(uint8_t irq, void(*handler)())
 	{
-		s_interruptables[irq] = interruptable;
+		s_irq_handlers[irq] = handler;
 	}
 
 	extern "C" void isr0();

kernel/include/kernel/APIC.h

@@ -4,9 +4,6 @@
 #include <kernel/InterruptController.h>
 #include <kernel/Memory/Types.h>
 
-namespace Kernel
-{
-
 class APIC final : public InterruptController
 {
 public:
@@ -55,5 +52,3 @@ namespace Kernel
 	BAN::Vector<IOAPIC>		m_io_apics;	
 	uint8_t					m_irq_overrides[0x100] {};
 };
-
-}

kernel/include/kernel/IDT.h

@@ -4,10 +4,11 @@
 
 constexpr uint8_t IRQ_VECTOR_BASE = 0x20;
 
-namespace Kernel::IDT
+namespace IDT
 {
 
 	void initialize();
+	void register_irq_handler(uint8_t irq, void(*f)());
 	[[noreturn]] void force_triple_fault();
 
 }

kernel/include/kernel/Input/PS2Config.h

@@ -1,97 +0,0 @@
-#pragma once
-
-#include <stdint.h>
-
-namespace Kernel::Input::PS2
-{
-
-	enum IOPort : uint8_t
-	{
-		DATA = 0x60,
-		STATUS = 0x64,
-		COMMAND = 0x64,
-	};
-
-	enum Status : uint8_t
-	{
-		OUTPUT_FULL = (1 << 0),
-		INPUT_FULL = (1 << 1),
-		SYSTEM = (1 << 2),
-		DEVICE_OR_CONTROLLER = (1 << 3),
-		TIMEOUT_ERROR = (1 << 6),
-		PARITY_ERROR = (1 << 7),
-	};
-
-	enum Config : uint8_t
-	{
-		INTERRUPT_FIRST_PORT = (1 << 0),
-		INTERRUPT_SECOND_PORT = (1 << 1),
-		SYSTEM_FLAG = (1 << 2),
-		ZERO1 = (1 << 3),
-		CLOCK_FIRST_PORT = (1 << 4),
-		CLOCK_SECOND_PORT = (1 << 5),
-		TRANSLATION_FIRST_PORT = (1 << 6),
-		ZERO2 = (1 << 7),
-	};
-
-	enum Command : uint8_t
-	{
-		READ_CONFIG = 0x20,
-		WRITE_CONFIG = 0x60,
-		DISABLE_SECOND_PORT = 0xA7,
-		ENABLE_SECOND_PORT = 0xA8,
-		TEST_SECOND_PORT = 0xA9,
-		TEST_CONTROLLER = 0xAA,
-		TEST_FIRST_PORT = 0xAB,
-		DISABLE_FIRST_PORT = 0xAD,
-		ENABLE_FIRST_PORT = 0xAE,
-		WRITE_TO_SECOND_PORT = 0xD4,
-	};
-
-	enum Response : uint8_t
-	{
-		TEST_FIRST_PORT_PASS = 0x00,
-		TEST_SECOND_PORT_PASS = 0x00,
-		TEST_CONTROLLER_PASS = 0x55,
-		SELF_TEST_PASS = 0xAA,
-		ACK = 0xFA,
-	};
-
-	enum DeviceCommand : uint8_t
-	{
-		ENABLE_SCANNING = 0xF4,
-		DISABLE_SCANNING = 0xF5,
-		IDENTIFY = 0xF2,
-		RESET = 0xFF,
-	};
-
-	enum IRQ : uint8_t
-	{
-		DEVICE0 = 1,
-		DEVICE1 = 12,
-	};
-
-	enum KBResponse : uint8_t
-	{
-		KEY_ERROR_OR_BUFFER_OVERRUN1 = 0x00,
-		SELF_TEST_PASSED = 0xAA,
-		ECHO_RESPONSE = 0xEE,
-		RESEND = 0xFE,
-		KEY_ERROR_OR_BUFFER_OVERRUN2 = 0xFF,
-	};
-
-	enum KBScancode : uint8_t
-	{
-		SET_SCANCODE_SET1 = 1,
-		SET_SCANCODE_SET2 = 2,
-		SET_SCANCODE_SET3 = 3,
-	};
-
-	enum KBLeds : uint8_t
-	{
-		SCROLL_LOCK	= (1 << 0),
-		NUM_LOCK	= (1 << 1),
-		CAPS_LOCK	= (1 << 2),
-	};
-
-}

kernel/include/kernel/Input/PS2Controller.h

@@ -1,15 +1,15 @@
 #pragma once
 
 #include <kernel/Device/Device.h>
-#include <kernel/InterruptController.h>
 
 namespace Kernel::Input
 {
 
-	class PS2Device : public CharacterDevice, public Interruptable
+	class PS2Device : public CharacterDevice
 	{
 	public:
 		virtual ~PS2Device() {}
+		virtual void on_byte(uint8_t) = 0;
 		
 	public:
 		PS2Device()
@@ -33,6 +33,9 @@ namespace Kernel::Input
 		BAN::ErrorOr<void> reset_device(uint8_t);
 		BAN::ErrorOr<void> set_scanning(uint8_t, bool);
 
+		static void device0_irq();
+		static void device1_irq();
+
 	private:
 		PS2Device* m_devices[2] { nullptr, nullptr };
 	};

kernel/include/kernel/Input/PS2Keyboard.h

@@ -29,7 +29,7 @@ namespace Kernel::Input
 	public:
 		static BAN::ErrorOr<PS2Keyboard*> create(PS2Controller&);
 
-		virtual void handle_irq() override;
+		virtual void on_byte(uint8_t) override;
 		virtual void update() override;
 
 	private:

kernel/include/kernel/InterruptController.h

@@ -5,24 +5,6 @@
 #define DISABLE_INTERRUPTS() asm volatile("cli")
 #define ENABLE_INTERRUPTS() asm volatile("sti")
 
-namespace Kernel
-{
-
-	class Interruptable
-	{
-	public:
-		Interruptable() = default;
-
-		void set_irq(int irq);
-		void enable_interrupt();
-		void disable_interrupt();
-
-		virtual void handle_irq() = 0;
-
-	private:
-		int m_irq { -1 };
-	};
-
 class InterruptController
 {
 public:
@@ -42,5 +24,3 @@ namespace Kernel
 };
 
 bool interrupts_enabled();
-
-}

kernel/include/kernel/PIC.h

@@ -2,9 +2,6 @@
 
 #include <kernel/InterruptController.h>
 
-namespace Kernel
-{
-
 class PIC final : public InterruptController
 {
 public:
@@ -19,5 +16,3 @@ namespace Kernel
 	static PIC* create();
 	friend class InterruptController;
 };
-
-}

kernel/include/kernel/Storage/ATABus.h

@@ -1,7 +1,6 @@
 #pragma once
 
 #include <BAN/Errors.h>
-#include <kernel/InterruptController.h>
 #include <kernel/SpinLock.h>
 #include <kernel/Storage/ATAController.h>
 
@@ -10,7 +9,7 @@ namespace Kernel
 
 	class ATADevice;
 
-	class ATABus : public Interruptable
+	class ATABus
 	{
 	public:
 		enum class DeviceType
@@ -28,7 +27,7 @@ namespace Kernel
 
 		ATAController& controller() { return m_controller; }
 
-		virtual void handle_irq() override;
+		void on_irq();
 
 	private:
 		ATABus(ATAController& controller, uint16_t base, uint16_t ctrl)

kernel/include/kernel/Terminal/Serial.h

@@ -1,8 +1,6 @@
 #pragma once
 
-#include <BAN/CircularQueue.h>
 #include <BAN/Errors.h>
-#include <kernel/InterruptController.h>
 #include <kernel/Terminal/TTY.h>
 
 namespace Kernel
@@ -36,7 +34,7 @@ namespace Kernel
 		uint32_t m_height { 0 };
 	};
 
-	class SerialTTY final : public TTY, public Interruptable
+	class SerialTTY final : public TTY
 	{
 	public:
 		static BAN::ErrorOr<BAN::RefPtr<SerialTTY>> create(Serial);
@@ -47,8 +45,6 @@ namespace Kernel
 
 		virtual void update() override;
 
-		virtual void handle_irq() override;
-
 	protected:
 		virtual BAN::StringView name() const override { return m_name; }
 
@@ -59,7 +55,6 @@ namespace Kernel
 	private:
 		BAN::String m_name;
 		Serial m_serial;
-		BAN::CircularQueue<uint8_t, 128> m_input;
 
 	public:
 		virtual dev_t rdev() const override { return m_rdev; }

kernel/include/kernel/Timer/HPET.h

@@ -1,12 +1,11 @@
 #pragma once
 
-#include <kernel/InterruptController.h>
 #include <kernel/Timer/Timer.h>
 
 namespace Kernel
 {
 
-	class HPET final : public Timer, public Interruptable
+	class HPET final : public Timer
 	{
 	public:
 		static BAN::ErrorOr<BAN::UniqPtr<HPET>> create(bool force_pic);
@@ -14,8 +13,6 @@ namespace Kernel
 		virtual uint64_t ms_since_boot() const override;
 		virtual timespec time_since_boot() const override;
 
-		virtual void handle_irq() override;
-
 	private:
 		HPET() = default;
 		BAN::ErrorOr<void> initialize(bool force_pic);

kernel/include/kernel/Timer/PIT.h

@@ -1,12 +1,14 @@
 #pragma once
 
-#include <kernel/InterruptController.h>
 #include <kernel/Timer/Timer.h>
+#include <stdint.h>
+
+#define PIT_IRQ 0
 
 namespace Kernel
 {
 
-	class PIT final : public Timer, public Interruptable
+	class PIT final : public Timer
 	{
 	public:
 		static BAN::ErrorOr<BAN::UniqPtr<PIT>> create();
@@ -14,13 +16,8 @@ namespace Kernel
 		virtual uint64_t ms_since_boot() const override;
 		virtual timespec time_since_boot() const override;
 
-		virtual void handle_irq() override;
-
 	private:
 		void initialize();
-
-	private:
-		volatile uint64_t m_system_time { 0 };
 	};
 
 }

kernel/kernel/APIC.cpp

@@ -20,9 +20,6 @@
 
 // https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#multiple-apic-description-table-madt-format
 
-namespace Kernel
-{
-
 struct MADT : public Kernel::ACPI::SDTHeader
 {
 	uint32_t local_apic;
@@ -85,6 +82,8 @@ namespace Kernel
 	};
 };
 
+using namespace Kernel;
+
 APIC* APIC::create()
 {
 	uint32_t ecx, edx;
@@ -257,5 +256,3 @@ namespace Kernel
 	uint32_t isr = read_from_local_apic(LAPIC_IS_REG + dword * 0x10);
 	return isr & (1 << bit);
 }
-
-}

kernel/kernel/Debug.cpp

@@ -76,13 +76,13 @@ namespace Debug
 
 	void DebugLock::lock()
 	{
-		if (Kernel::interrupts_enabled())
+		if (interrupts_enabled())
 			s_debug_lock.lock();
 	}
 
 	void DebugLock::unlock()
 	{
-		if (Kernel::interrupts_enabled())
+		if (interrupts_enabled())
 			s_debug_lock.unlock();
 	}
 

kernel/kernel/Input/PS2Controller.cpp

@@ -2,7 +2,6 @@
 #include <kernel/ACPI.h>
 #include <kernel/FS/DevFS/FileSystem.h>
 #include <kernel/IDT.h>
-#include <kernel/Input/PS2Config.h>
 #include <kernel/Input/PS2Controller.h>
 #include <kernel/Input/PS2Keyboard.h>
 #include <kernel/InterruptController.h>
@@ -12,6 +11,77 @@
 namespace Kernel::Input
 {
 
+	namespace PS2
+	{
+
+		enum IOPort : uint8_t
+		{
+			DATA = 0x60,
+			STATUS = 0x64,
+			COMMAND = 0x64,
+		};
+
+		enum Status : uint8_t
+		{
+			OUTPUT_FULL = (1 << 0),
+			INPUT_FULL = (1 << 1),
+			SYSTEM = (1 << 2),
+			DEVICE_OR_CONTROLLER = (1 << 3),
+			TIMEOUT_ERROR = (1 << 6),
+			PARITY_ERROR = (1 << 7),
+		};
+
+		enum Config : uint8_t
+		{
+			INTERRUPT_FIRST_PORT = (1 << 0),
+			INTERRUPT_SECOND_PORT = (1 << 1),
+			SYSTEM_FLAG = (1 << 2),
+			ZERO1 = (1 << 3),
+			CLOCK_FIRST_PORT = (1 << 4),
+			CLOCK_SECOND_PORT = (1 << 5),
+			TRANSLATION_FIRST_PORT = (1 << 6),
+			ZERO2 = (1 << 7),
+		};
+
+		enum Command : uint8_t
+		{
+			READ_CONFIG = 0x20,
+			WRITE_CONFIG = 0x60,
+			DISABLE_SECOND_PORT = 0xA7,
+			ENABLE_SECOND_PORT = 0xA8,
+			TEST_SECOND_PORT = 0xA9,
+			TEST_CONTROLLER = 0xAA,
+			TEST_FIRST_PORT = 0xAB,
+			DISABLE_FIRST_PORT = 0xAD,
+			ENABLE_FIRST_PORT = 0xAE,
+			WRITE_TO_SECOND_PORT = 0xD4,
+		};
+
+		enum Response
+		{
+			TEST_FIRST_PORT_PASS = 0x00,
+			TEST_SECOND_PORT_PASS = 0x00,
+			TEST_CONTROLLER_PASS = 0x55,
+			SELF_TEST_PASS = 0xAA,
+			ACK = 0xFA,
+		};
+
+		enum DeviceCommand
+		{
+			ENABLE_SCANNING = 0xF4,
+			DISABLE_SCANNING = 0xF5,
+			IDENTIFY = 0xF2,
+			RESET = 0xFF,
+		};
+
+		enum IRQ
+		{
+			DEVICE0 = 1,
+			DEVICE1 = 12,
+		};
+
+	}
+
 	static constexpr uint64_t s_device_timeout_ms = 100;
 
 	static void controller_send_command(PS2::Command command)
@@ -66,6 +136,20 @@ namespace Kernel::Input
 		return {};
 	}
 
+	void PS2Controller::device0_irq()
+	{
+		auto& controller = PS2Controller::get();
+		ASSERT(controller.m_devices[0] != nullptr);
+		controller.m_devices[0]->on_byte(IO::inb(PS2::IOPort::DATA));
+	}
+
+	void PS2Controller::device1_irq()
+	{
+		auto& controller = PS2Controller::get();
+		ASSERT(controller.m_devices[1] != nullptr);
+		controller.m_devices[1]->on_byte(IO::inb(PS2::IOPort::DATA));
+	}
+
 	static PS2Controller* s_instance = nullptr;
 
 	BAN::ErrorOr<void> PS2Controller::initialize()
@@ -172,15 +256,15 @@ namespace Kernel::Input
 
 		if (m_devices[0])
 		{
-			m_devices[0]->set_irq(PS2::IRQ::DEVICE0);
+			IDT::register_irq_handler(PS2::IRQ::DEVICE0, device0_irq);
-			m_devices[0]->enable_interrupt();
+			InterruptController::get().enable_irq(PS2::IRQ::DEVICE0);
 			config |= PS2::Config::INTERRUPT_FIRST_PORT;
 			DevFileSystem::get().add_device("input0", m_devices[0]);
 		}
 		if (m_devices[1])
 		{
-			m_devices[1]->set_irq(PS2::IRQ::DEVICE1);
+			IDT::register_irq_handler(PS2::IRQ::DEVICE1, device1_irq);
-			m_devices[1]->enable_interrupt();
+			InterruptController::get().enable_irq(PS2::IRQ::DEVICE1);
 			config |= PS2::Config::INTERRUPT_SECOND_PORT;
 			DevFileSystem::get().add_device("input1", m_devices[1]);
 		}

kernel/kernel/Input/PS2Keyboard.cpp

@@ -1,9 +1,7 @@
 #include <BAN/ScopeGuard.h>
 #include <kernel/CriticalScope.h>
 #include <kernel/FS/DevFS/FileSystem.h>
-#include <kernel/Input/PS2Config.h>
 #include <kernel/Input/PS2Keyboard.h>
-#include <kernel/IO.h>
 #include <kernel/Timer/Timer.h>
 
 #include <sys/sysmacros.h>
@@ -14,6 +12,35 @@
 namespace Kernel::Input
 {
 
+	namespace PS2
+	{
+
+		enum Response
+		{
+			KEY_ERROR_OR_BUFFER_OVERRUN1 = 0x00,
+			SELF_TEST_PASSED = 0xAA,
+			ECHO_RESPONSE = 0xEE,
+			ACK = 0xFA,
+			RESEND = 0xFE,
+			KEY_ERROR_OR_BUFFER_OVERRUN2 = 0xFF,
+		};
+
+		enum Scancode
+		{
+			SET_SCANCODE_SET1 = 1,
+			SET_SCANCODE_SET2 = 2,
+			SET_SCANCODE_SET3 = 3,
+		};
+
+		enum Leds
+		{
+			SCROLL_LOCK	= (1 << 0),
+			NUM_LOCK	= (1 << 1),
+			CAPS_LOCK	= (1 << 2),
+		};
+
+	}
+
 	BAN::ErrorOr<PS2Keyboard*> PS2Keyboard::create(PS2Controller& controller)
 	{
 		PS2Keyboard* keyboard = new PS2Keyboard(controller);
@@ -30,10 +57,8 @@ namespace Kernel::Input
 		, m_rdev(makedev(DevFileSystem::get().get_next_dev(), 0))
 	{ }
 
-	void PS2Keyboard::handle_irq()
+	void PS2Keyboard::on_byte(uint8_t byte)
 	{
-		uint8_t byte = IO::inb(PS2::IOPort::DATA);
-
 		// NOTE: This implementation does not allow using commands
 		//       that respond with more bytes than ACK
 		switch (m_state)
@@ -46,11 +71,11 @@ namespace Kernel::Input
 						m_command_queue.pop();
 						m_state = State::Normal;
 						break;
-					case PS2::KBResponse::RESEND:
+					case PS2::Response::RESEND:
 						m_state = State::Normal;
 						break;
-					case PS2::KBResponse::KEY_ERROR_OR_BUFFER_OVERRUN1:
+					case PS2::Response::KEY_ERROR_OR_BUFFER_OVERRUN1:
-					case PS2::KBResponse::KEY_ERROR_OR_BUFFER_OVERRUN2:
+					case PS2::Response::KEY_ERROR_OR_BUFFER_OVERRUN2:
 						dwarnln("Key detection error or internal buffer overrun");
 						break;
 					default:
@@ -72,7 +97,7 @@ namespace Kernel::Input
 	BAN::ErrorOr<void> PS2Keyboard::initialize()
 	{
 		append_command_queue(Command::SET_LEDS, 0x00);
-		append_command_queue(Command::SCANCODE, PS2::KBScancode::SET_SCANCODE_SET2);
+		append_command_queue(Command::SCANCODE, PS2::Scancode::SET_SCANCODE_SET2);
 		append_command_queue(Command::ENABLE_SCANNING);
 		return {};
 	}
@@ -209,11 +234,11 @@ namespace Kernel::Input
 	{
 		uint8_t new_leds = 0;
 		if (m_modifiers & (uint8_t)Input::KeyEvent::Modifier::ScrollLock)
-			new_leds |= PS2::KBLeds::SCROLL_LOCK;
+			new_leds |= PS2::Leds::SCROLL_LOCK;
 		if (m_modifiers & (uint8_t)Input::KeyEvent::Modifier::NumLock)
-			new_leds |= PS2::KBLeds::NUM_LOCK;
+			new_leds |= PS2::Leds::NUM_LOCK;
 		if (m_modifiers & (uint8_t)Input::KeyEvent::Modifier::CapsLock)
-			new_leds |= PS2::KBLeds::CAPS_LOCK;
+			new_leds |= PS2::Leds::CAPS_LOCK;
 		append_command_queue(Command::SET_LEDS, new_leds);
 	}
 

kernel/kernel/InterruptController.cpp

@@ -5,32 +5,8 @@
 
 #include <lai/helpers/sci.h>
 
-namespace Kernel
-{
-
-	namespace IDT { void register_irq_handler(uint8_t irq, Interruptable*); }
-
 static InterruptController* s_instance = nullptr;
 
-	void Interruptable::set_irq(int irq)
-	{
-		if (m_irq != -1)
-			IDT::register_irq_handler(m_irq, nullptr);
-		m_irq = irq;
-		IDT::register_irq_handler(irq, this);
-	}
-
-	void Interruptable::enable_interrupt()
-	{
-		ASSERT(m_irq != -1);
-		InterruptController::get().enable_irq(m_irq);
-	}
-
-	void Interruptable::disable_interrupt()
-	{
-		ASSERT_NOT_REACHED();
-	}
-
 InterruptController& InterruptController::get()
 {
 	ASSERT(s_instance);
@@ -73,5 +49,3 @@ namespace Kernel
 	asm volatile("pushf; pop %0" : "=r"(flags) :: "memory");
 	return flags & (1 << 9);
 }
-
-}

kernel/kernel/Memory/PhysicalRange.cpp

@@ -66,7 +66,7 @@ namespace Kernel
 		ASSERT(page->next == nullptr);
 
 		// Detatch page from top of the free list
-		m_free_list = m_free_list->prev;
+		m_free_list = m_free_list->prev ? m_free_list->prev : nullptr;
 		if (m_free_list)
 			m_free_list->next = nullptr;
 

kernel/kernel/PIC.cpp

@@ -17,9 +17,6 @@
 
 #define ICW4_8086	0x01
 
-namespace Kernel
-{
-
 PIC* PIC::create()
 {
 	mask_all();
@@ -97,5 +94,3 @@ namespace Kernel
 	IO::outb(port, PIC_ISR);
 	return IO::inb(port) & (1 << irq);
 }
-
-}

kernel/kernel/Storage/ATABus.cpp

@@ -11,6 +11,40 @@
 namespace Kernel
 {
 
+	static void bus_irq_handler0();
+	static void bus_irq_handler1();
+
+	struct BusIRQ
+	{
+		ATABus* bus { nullptr };
+		void (*handler)() { nullptr };
+		uint8_t irq { 0 };
+	};
+	static BusIRQ s_bus_irqs[] {
+		{ nullptr, bus_irq_handler0, 0 },
+		{ nullptr, bus_irq_handler1, 0 },
+	};
+
+	static void bus_irq_handler0() { ASSERT(s_bus_irqs[0].bus); s_bus_irqs[0].bus->on_irq(); }
+	static void bus_irq_handler1() { ASSERT(s_bus_irqs[1].bus); s_bus_irqs[1].bus->on_irq(); }
+
+	static void register_bus_irq_handler(ATABus* bus, uint8_t irq)
+	{
+		for (uint8_t i = 0; i < sizeof(s_bus_irqs) / sizeof(BusIRQ); i++)
+		{
+			if (s_bus_irqs[i].bus == nullptr)
+			{
+				s_bus_irqs[i].bus = bus;
+				s_bus_irqs[i].irq = irq;
+
+				IDT::register_irq_handler(irq, s_bus_irqs[i].handler);
+				InterruptController::get().enable_irq(irq);
+				return;
+			}
+		}
+		ASSERT_NOT_REACHED();
+	}
+
 	ATABus* ATABus::create(ATAController& controller, uint16_t base, uint16_t ctrl, uint8_t irq)
 	{
 		ATABus* bus = new ATABus(controller, base, ctrl);
@@ -21,11 +55,11 @@ namespace Kernel
 
 	void ATABus::initialize(uint8_t irq)
 	{
-		set_irq(irq);
+		register_bus_irq_handler(this, irq);
-		enable_interrupt();
 
-		BAN::Vector<uint16_t> identify_buffer;
+		uint16_t* identify_buffer = new uint16_t[256];
-		MUST(identify_buffer.resize(256));
+		ASSERT(identify_buffer);
+		BAN::ScopeGuard _([identify_buffer] { delete[] identify_buffer; });
 
 		for (uint8_t i = 0; i < 2; i++)
 		{
@@ -38,11 +72,11 @@ namespace Kernel
 
 			BAN::ScopeGuard guard([this, i] { m_devices[i] = nullptr; });
 
-			auto type = identify(device, identify_buffer.data());
+			auto type = identify(device, identify_buffer);
 			if (type == DeviceType::None)
 				continue;
 
-			auto res = device.initialize(type, identify_buffer.data());
+			auto res = device.initialize(type, identify_buffer);
 			if (res.is_error())
 			{
 				dprintln("{}", res.error());
@@ -115,7 +149,7 @@ namespace Kernel
 		return type;
 	}
 
-	void ATABus::handle_irq()
+	void ATABus::on_irq()
 	{
 		ASSERT(!m_has_got_irq);
 		if (io_read(ATA_PORT_STATUS) & ATA_STATUS_ERR)

kernel/kernel/Terminal/Serial.cpp

@@ -1,4 +1,5 @@
 #include <BAN/Array.h>
+#include <BAN/CircularQueue.h>
 #include <kernel/CriticalScope.h>
 #include <kernel/FS/DevFS/FileSystem.h>
 #include <kernel/IDT.h>
@@ -37,9 +38,37 @@ namespace Kernel
 	static BAN::Array<Serial, sizeof(s_serial_ports) / sizeof(*s_serial_ports)> s_serial_drivers;
 	static bool s_has_devices { false };
 
+	static BAN::CircularQueue<uint8_t, 128> s_com1_input;
+	static BAN::CircularQueue<uint8_t, 128> s_com2_input;
 	static BAN::RefPtr<SerialTTY> s_com1;
 	static BAN::RefPtr<SerialTTY> s_com2;
 
+	static void irq3_handler()
+	{
+		if (!s_serial_drivers[1].is_valid())
+			return;
+		uint8_t ch = IO::inb(COM2_PORT);
+		if (s_com2_input.full())
+		{
+			dwarnln("COM2 buffer full");
+			s_com2_input.pop();
+		}
+		s_com2_input.push(ch);
+	}
+
+	static void irq4_handler()
+	{
+		if (!s_serial_drivers[0].is_valid())
+			return;
+		uint8_t ch = IO::inb(COM1_PORT);
+		if (s_com1_input.full())
+		{
+			dwarnln("COM1 buffer full");
+			s_com1_input.pop();
+		}
+		s_com1_input.push(ch);
+	}
+
 	static dev_t next_rdev()
 	{
 		static dev_t major = DevFileSystem::get().get_next_dev();
@@ -191,14 +220,14 @@ namespace Kernel
 		if (serial.port() == COM1_PORT)
 		{
 			IO::outb(COM1_PORT + 1, 1);
-			tty->set_irq(COM1_IRQ);
+			InterruptController::get().enable_irq(COM1_IRQ);
-			tty->enable_interrupt();
+			IDT::register_irq_handler(COM1_IRQ, irq4_handler);
 		}
 		else if (serial.port() == COM2_PORT)
 		{
 			IO::outb(COM2_PORT + 1, 1);
-			tty->set_irq(COM2_IRQ);
+			InterruptController::get().enable_irq(COM2_IRQ);
-			tty->enable_interrupt();
+			IDT::register_irq_handler(COM2_IRQ, irq3_handler);
 		}
 
 		auto ref_ptr = BAN::RefPtr<SerialTTY>::adopt(tty);
@@ -210,45 +239,41 @@ namespace Kernel
 		return ref_ptr;
 	}
 
-	void SerialTTY::handle_irq()
-	{
-		uint8_t ch = IO::inb(m_serial.port());
-		if (m_input.full())
-		{
-			dwarnln("Serial buffer full");
-			m_input.pop();
-		}
-		m_input.push(ch);
-	}
-
 	void SerialTTY::update()
 	{
 		if (m_serial.port() != COM1_PORT && m_serial.port() != COM2_PORT)
 			return;
 
-		uint8_t buffer[128];
+		static uint8_t buffer[128];
 
+		auto update_com =
+			[&](auto& device, auto& input_queue)
 			{
-			CriticalScope _;
+				if (input_queue.empty())
-			if (m_input.empty())
 					return;
 				uint8_t* ptr = buffer;
-			while (!m_input.empty())
+				while (!input_queue.empty())
 				{
-				*ptr = m_input.front();
+					*ptr = input_queue.front();
 					if (*ptr == '\r')
 						*ptr = '\n';
 					if (*ptr == 127)
 						*ptr++ = '\b', *ptr++ = ' ', *ptr = '\b';
-				m_input.pop();
+					input_queue.pop();
 					ptr++;
 				}
 				*ptr = '\0';
-		}
 
-		const uint8_t* ptr = buffer;
+				ptr = buffer;
 				while (*ptr)
-			handle_input_byte(*ptr++);
+					device->handle_input_byte(*ptr++);
+			};
+
+		CriticalScope _;
+		if (m_serial.port() == COM1_PORT)
+			update_com(s_com1, s_com1_input);
+		if (m_serial.port() == COM2_PORT)
+			update_com(s_com2, s_com2_input);
 	}
 
 	uint32_t SerialTTY::width() const

kernel/kernel/Timer/HPET.cpp

@@ -131,17 +131,12 @@ namespace Kernel
 		for (int i = 1; i <= header->comparator_count; i++)
 			write_register(HPET_REG_TIMER_CONFIG(i), 0);
 
-		set_irq(irq);
+		IDT::register_irq_handler(irq, [] { Scheduler::get().timer_reschedule(); });
-		enable_interrupt();
+		InterruptController::get().enable_irq(irq);
 
 		return {};
 	}
 
-	void HPET::handle_irq()
-	{
-		Scheduler::get().timer_reschedule();
-	}
-
 	uint64_t HPET::ms_since_boot() const
 	{
 		// FIXME: 32 bit CPUs should use 32 bit counter with 32 bit reads

kernel/kernel/Timer/PIT.cpp

@@ -4,8 +4,6 @@
 #include <kernel/Scheduler.h>
 #include <kernel/Timer/PIT.h>
 
-#define PIT_IRQ 0
-
 #define TIMER0_CTL			0x40
 #define TIMER1_CTL			0x41
 #define TIMER2_CTL			0x42
@@ -29,6 +27,14 @@
 namespace Kernel
 {
 
+	static volatile uint64_t s_system_time = 0;
+
+	void irq_handler()
+	{
+		s_system_time = s_system_time + 1;
+		Kernel::Scheduler::get().timer_reschedule();
+	}
+
 	BAN::ErrorOr<BAN::UniqPtr<PIT>> PIT::create()
 	{
 		PIT* pit = new PIT();
@@ -47,24 +53,19 @@ namespace Kernel
 		IO::outb(TIMER0_CTL, (timer_reload >> 0) & 0xff);
 		IO::outb(TIMER0_CTL, (timer_reload >> 8) & 0xff);
 
-		set_irq(PIT_IRQ);
+		IDT::register_irq_handler(PIT_IRQ, irq_handler);
-		enable_interrupt();
-	}
 
-	void PIT::handle_irq()
+		InterruptController::get().enable_irq(PIT_IRQ);
-	{
-		m_system_time = m_system_time + 1;
-		Kernel::Scheduler::get().timer_reschedule();
 	}
 
 	uint64_t PIT::ms_since_boot() const
 	{
-		return m_system_time * (MS_PER_S / TICKS_PER_SECOND);
+		return s_system_time * (MS_PER_S / TICKS_PER_SECOND);
 	}
 
 	timespec PIT::time_since_boot() const
 	{
-		uint64_t ticks = m_system_time;
+		uint64_t ticks = s_system_time;
 		return timespec {
 			.tv_sec = ticks / TICKS_PER_SECOND,
 			.tv_nsec = (long)((ticks % TICKS_PER_SECOND) * (NS_PER_S / TICKS_PER_SECOND))