xv6-cs450/trap.c

#include "types.h"
#include "param.h"
#include "mmu.h"
#include "proc.h"
#include "defs.h"
#include "x86.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();


int xx;

void
tinit()
{
  int i;

  xx = 0;
  for(i = 0; i < 256; i++){
    SETGATE(idt[i], 1, SEG_KCODE << 3, vectors[i], 3);
  }
  asm volatile("lidt %0" : : "g" (idt_pd.pd_lim));
}

void
trap(struct Trapframe *tf)
{
  /* which process are we running? */
  if(xx < 10)
    cprintf("%d\n", tf->tf_trapno);
  xx++;
  //while(1)
  //;
  // XXX probably ought to lgdt on trap return
}