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#include <kernel/syscall.h>
#include <kernel/panic.h>
#include <kernel/gdt.h>
#include <kernel/isr.h>
#include <kernel/io.h>
#include <kernel/pic.h>
#include <kernel/string.h>
#include <kernel/paging.h>
#include <stdint.h>
__attribute__((aligned(0x10)))
struct idt_entry idt[256];
struct idt_ptr idtr;
const char* exceptions[] = {
"Division by zero",
"Debug",
"Non-maskable interrupt",
"Breakpoint",
"Overflow",
"Out-of-bounds",
"Invalid opcode",
"FPU not available",
"Double fault",
"RESERVED",
"Invalid TSS",
"Segment not present",
"Stack fault",
"General protection fault",
"Page fault",
"RESERVED",
"FPU exception",
"Alignment check",
"Machine check",
"FPU-SIMD exception",
"Virtualization exception",
"Control protection"
"RESERVED",
"Hypervisor injection",
"VMM exception",
"Security exception",
"RESERVED",
"Triple fault",
"RESERVED"
};
__attribute__((noreturn))
void halt_catch_fire(struct isr_frame *frame) {
dump_reg(frame);
kprintf("ERRNO=%x\n", frame->errno);
__asm__ volatile("cli;hlt");
while (1);
}
void exception_handler(struct isr_frame *frame) {
switch (frame->vector) {
case 0x00:
panic("Division by zero in kernel address space");
halt_catch_fire(frame);
case 0x06:
panic("Invalid opcode in kernel address space");
halt_catch_fire(frame);
case 0x08:
panic("Double fault in interrupt handler");
halt_catch_fire(frame);
case 0x0D:
panic("Protection fault in kernel address space");
halt_catch_fire(frame);
case 0x0E:
page_fault_handler(frame);
break;
default:
panic("Unhandled exception");
halt_catch_fire(frame);
}
}
void interrupt_handler(struct isr_frame frame) {
if (frame.vector < 32) {
exception_handler(&frame);
} else if (frame.vector < 48) {
irq_dispatch(&frame);
} else {
switch (frame.vector) {
case 0x80:
handle_syscall(&frame);
break;
default:
panic("Unmapped interrupt");
halt_catch_fire(&frame);
__asm__ volatile("cli;hlt");
}
}
}
void idt_set_gate(uint8_t num, void (*handler)(void), uint16_t cs, uint8_t flags) {
struct idt_entry *desc = &idt[num];
desc->isr_low = (uint16_t)(((uint32_t)handler >> 0) & 0xFFFF);
desc->isr_high = (uint16_t)(((uint32_t)handler >> 16) & 0xFFFF);
desc->reserved = 0;
desc->kernel_cs = cs;
desc->flags = flags;
}
void idt_install(void) {
idtr.limit = (uint16_t)sizeof(struct idt_entry) * 256 - 1;
idtr.base = (uint32_t)idt;
idt_set_gate(0x0, isr_stub_0, 0x08, IDT_EXCEPTION);
idt_set_gate(0x1, isr_stub_1, 0x08, IDT_EXCEPTION);
idt_set_gate(0x2, isr_stub_2, 0x08, IDT_EXCEPTION);
idt_set_gate(0x3, isr_stub_3, 0x08, IDT_EXCEPTION);
idt_set_gate(0x4, isr_stub_4, 0x08, IDT_EXCEPTION);
idt_set_gate(0x5, isr_stub_5, 0x08, IDT_EXCEPTION);
idt_set_gate(0x6, isr_stub_6, 0x08, IDT_EXCEPTION);
idt_set_gate(0x7, isr_stub_7, 0x08, IDT_EXCEPTION);
idt_set_gate(0x8, isr_stub_8, 0x08, IDT_EXCEPTION);
idt_set_gate(0x9, isr_stub_9, 0x08, IDT_EXCEPTION);
idt_set_gate(0xA, isr_stub_10, 0x08, IDT_EXCEPTION);
idt_set_gate(0xB, isr_stub_11, 0x08, IDT_EXCEPTION);
idt_set_gate(0xC, isr_stub_12, 0x08, IDT_EXCEPTION);
idt_set_gate(0xD, isr_stub_13, 0x08, IDT_EXCEPTION);
idt_set_gate(0xE, isr_stub_14, 0x08, IDT_EXCEPTION);
idt_set_gate(0xF, isr_stub_15, 0x08, IDT_EXCEPTION);
idt_set_gate(0x10, isr_stub_16, 0x08, IDT_EXCEPTION);
idt_set_gate(0x11, isr_stub_17, 0x08, IDT_EXCEPTION);
idt_set_gate(0x12, isr_stub_18, 0x08, IDT_EXCEPTION);
idt_set_gate(0x13, isr_stub_19, 0x08, IDT_EXCEPTION);
idt_set_gate(0x14, isr_stub_20, 0x08, IDT_EXCEPTION);
idt_set_gate(0x15, isr_stub_21, 0x08, IDT_EXCEPTION);
idt_set_gate(0x16, isr_stub_22, 0x08, IDT_EXCEPTION);
idt_set_gate(0x17, isr_stub_23, 0x08, IDT_EXCEPTION);
idt_set_gate(0x18, isr_stub_24, 0x08, IDT_EXCEPTION);
idt_set_gate(0x19, isr_stub_25, 0x08, IDT_EXCEPTION);
idt_set_gate(0x1A, isr_stub_26, 0x08, IDT_EXCEPTION);
idt_set_gate(0x1B, isr_stub_27, 0x08, IDT_EXCEPTION);
idt_set_gate(0x1C, isr_stub_28, 0x08, IDT_EXCEPTION);
idt_set_gate(0x1D, isr_stub_29, 0x08, IDT_EXCEPTION);
idt_set_gate(0x1E, isr_stub_30, 0x08, IDT_EXCEPTION);
idt_set_gate(0x1F, isr_stub_31, 0x08, IDT_EXCEPTION);
idt_set_gate(0x20, irq_stub_0, 0x08, IDT_INTERRUPT);
idt_set_gate(0x21, irq_stub_1, 0x08, IDT_INTERRUPT);
idt_set_gate(0x22, irq_stub_2, 0x08, IDT_INTERRUPT);
idt_set_gate(0x23, irq_stub_3, 0x08, IDT_INTERRUPT);
idt_set_gate(0x24, irq_stub_4, 0x08, IDT_INTERRUPT);
idt_set_gate(0x25, irq_stub_5, 0x08, IDT_INTERRUPT);
idt_set_gate(0x26, irq_stub_6, 0x08, IDT_INTERRUPT);
idt_set_gate(0x27, irq_stub_7, 0x08, IDT_INTERRUPT);
idt_set_gate(0x28, irq_stub_8, 0x08, IDT_INTERRUPT);
idt_set_gate(0x29, irq_stub_9, 0x08, IDT_INTERRUPT);
idt_set_gate(0x2A, irq_stub_10, 0x08, IDT_INTERRUPT);
idt_set_gate(0x2B, irq_stub_11, 0x08, IDT_INTERRUPT);
idt_set_gate(0x2C, irq_stub_12, 0x08, IDT_INTERRUPT);
idt_set_gate(0x2D, irq_stub_13, 0x08, IDT_INTERRUPT);
idt_set_gate(0x2E, irq_stub_14, 0x08, IDT_INTERRUPT);
idt_set_gate(0x2F, irq_stub_15, 0x08, IDT_INTERRUPT);
idt_set_gate(0x80, syscall_stub, 0x08, IDT_INTERRUPT);
__asm__ volatile("lidt %0" : : "memory"(idtr));
}
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