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#include "types.h"
#include "param.h"
#include "mmu.h"
#include "proc.h"
#include "defs.h"
#include "x86.h"
#include "traps.h"
struct Gatedesc idt[256];
struct Pseudodesc idt_pd = { 0, sizeof(idt) - 1, (unsigned) &idt };
extern unsigned vectors[]; /* vectors.S, array of 256 entry point addresses */
extern void trapenter();
extern void trapenter1();
void
tvinit()
{
int i;
for(i = 0; i < 256; i++){
SETGATE(idt[i], 1, SEG_KCODE << 3, vectors[i], 0);
}
SETGATE(idt[T_SYSCALL], T_SYSCALL, SEG_KCODE << 3, vectors[48], 3);
}
void
idtinit()
{
asm volatile("lidt %0" : : "g" (idt_pd.pd_lim));
}
void
trap(struct Trapframe *tf)
{
int v = tf->tf_trapno;
acquire_spinlock(&kernel_lock); // released in trapret in trapasm.S
if(v == T_SYSCALL){
curproc[cpu()]->tf = tf;
syscall();
return;
}
if(v == (IRQ_OFFSET + IRQ_TIMER)){
curproc[cpu()]->tf = tf;
lapic_timerintr();
return;
}
cprintf("trap %d eip %x:%x\n", tf->tf_trapno, tf->tf_cs, tf->tf_eip);
// XXX probably ought to lgdt on trap return
return;
}
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