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#include <kernel/arch/amd64/interrupts.h>
#include <kernel/arch/amd64/port_io.h>
#include <kernel/arch/generic.h>
#include <kernel/malloc.h>
#include <kernel/panic.h>
#include <kernel/proc.h>
#include <stdbool.h>
#include <stdint.h>
enum {
Nmi = 0x02,
GpFault = 0x0d,
PageFault = 0x0e,
};
typedef struct {
uint64_t ip, cs, flags;
/* only valid if switching from/into user mode */
uint64_t sp, ss;
} IretFrame;
typedef struct IsrFrame {
UserRegs regs; /* doesn't include ip, flags, sp */
uint64_t _retaddr;
uint64_t errcode;
IretFrame iret;
} __attribute__((packed)) IsrFrame;
void (*irq_fn[16])(void) = {0};
static uint64_t
getcr2(void)
{
uint64_t cr2;
asm("mov %%cr2, %0" : "=r"(cr2));
return cr2;
}
static void
log_interrupt(uint8_t inr, IsrFrame *sf)
{
IretFrame *iret = &sf->iret;
kprintf("interrupt %d, rip = k/%08x, cs 0x%x, code 0x%x\n",
inr, iret->ip, iret->cs, sf->errcode);
if ((iret->cs & 0x3) == 0) { /* ring 0? */
uint64_t *stack = (void*)iret->sp;
kprintf("kernel rsp = %p, *rsp = %p\n", stack, *stack);
}
if (inr == PageFault) {
kprintf("addr 0x%x\n", getcr2());
}
}
void
isr_stage3(uint8_t inr, IsrFrame *sf)
{
IretFrame *iret = &sf->iret;
uint8_t irqn = inr - IRQ_IBASE;
if (irqn < 16) {
if (irq_fn[irqn]) {
irq_fn[irqn]();
irq_eoi(irqn);
return;
}
}
if (inr == Nmi) { /* print some debugging information */
log_interrupt(inr, sf);
mem_debugprint();
return;
}
if ((iret->cs & 0x3) == 0) { /* ring 0? */
log_interrupt(inr, sf);
cpu_halt();
} else { /* in user */
if (inr == PageFault) {
char buf[64];
int len = snprintf(
buf, sizeof(buf),
"sys: fault %s ip=%p cr2=%p", /* format inspired by plan9 */
(sf->errcode & 2) ? "write" : "read",
sf->iret.ip,
getcr2()
);
/* save registers (ignoring SSE) */
proc_cur->regs = sf->regs;
proc_cur->regs.rsp = sf->iret.sp;
proc_cur->regs.rip = sf->iret.ip;
proc_cur->regs.flags = sf->iret.flags;
proc_intr(proc_cur, buf, len);
proc_intr_deliver(proc_cur);
/* restore */
sf->regs = proc_cur->regs;
sf->iret.sp = proc_cur->regs.rsp;
sf->iret.ip = proc_cur->regs.rip;
sf->iret.flags = proc_cur->regs.flags;
return;
}
proc_kill(proc_cur, inr);
proc_switch_any();
}
}
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