Files
banan-os/kernel/include/kernel/IDT.h
Bananymous 2f9b8b6fc9 Kernel/LibC: Rework userspace syscall interface
Kernel syscall API no longer zeros all unused argument registers and
libc now uses inlined syscall macro internally. This significantly
cleans up generated code for basic syscall wrapper functions.
2026-04-11 03:30:52 +03:00

92 lines
1.8 KiB
C++

#pragma once
#include <BAN/Array.h>
#include <BAN/NoCopyMove.h>
#include <kernel/Arch.h>
#include <kernel/Interruptable.h>
#include <stdint.h>
namespace Kernel
{
// IDT entries
// 0x00->0x1F (32): ISR
// 0x20->0x7F (96): PIC/IOAPIC
// 0x80->0xEF (112): MSI
// 0xF0->0xFE (15): internal
constexpr uint8_t IRQ_VECTOR_BASE = 0x20;
constexpr uint8_t IRQ_MSI_BASE = 0x80;
constexpr uint8_t IRQ_MSI_END = 0xF0;
#if ARCH(i686)
constexpr uint8_t IRQ_SYSCALL = 0xF0; // hard coded in kernel/API/Syscall.h
#endif
constexpr uint8_t IRQ_IPI = 0xF1;
constexpr uint8_t IRQ_TIMER = 0xF2;
#if ARCH(x86_64)
struct GateDescriptor
{
uint16_t offset0;
uint16_t selector;
uint8_t IST;
uint8_t flags;
uint16_t offset1;
uint32_t offset2;
uint32_t reserved;
};
static_assert(sizeof(GateDescriptor) == 16);
#elif ARCH(i686)
struct GateDescriptor
{
uint16_t offset0;
uint16_t selector;
uint8_t reserved;
uint8_t flags;
uint16_t offset1;
};
static_assert(sizeof(GateDescriptor) == 8);
#else
#error
#endif
struct IDTR
{
uint16_t size;
uintptr_t offset;
} __attribute__((packed));
class IDT
{
BAN_NON_COPYABLE(IDT);
BAN_NON_MOVABLE(IDT);
public:
static IDT* create();
[[noreturn]] static void force_triple_fault();
void register_irq_handler(uint8_t irq, Interruptable* interruptable);
void load()
{
asm volatile("lidt %0" :: "m"(m_idtr) : "memory");
}
private:
IDT() = default;
void register_interrupt_handler(uint8_t index, void (*handler)(), uint8_t ist = 0);
void register_syscall_handler(uint8_t index, void (*handler)());
private:
BAN::Array<GateDescriptor, 0x100> m_idt;
IDTR m_idtr {
.size = static_cast<uint16_t>(m_idt.size() * sizeof(GateDescriptor) - 1),
.offset = reinterpret_cast<uintptr_t>(m_idt.data())
};
};
}