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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"
#include "syscall.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;
if(v == T_SYSCALL){
struct proc *cp = curproc[cpu()];
if(cp == 0)
panic("syscall with no proc");
if(cp->killed)
proc_exit();
cp->tf = tf;
syscall();
if(cp != curproc[cpu()])
panic("trap ret wrong curproc");
if(cp->state != RUNNING)
panic("trap ret but not RUNNING");
if(tf != cp->tf)
panic("trap ret wrong tf");
if(read_esp() < (unsigned)cp->kstack ||
read_esp() >= (unsigned)cp->kstack + KSTACKSIZE)
panic("trap ret esp wrong");
if(cp->killed)
proc_exit();
return;
}
if(v == (IRQ_OFFSET + IRQ_TIMER)){
struct proc *cp = curproc[cpu()];
lapic_timerintr();
if(cp){
if(cpus[cpu()].clis != 0)
panic("trap clis > 0");
cpus[cpu()].clis += 1;
sti();
if(cp->killed)
proc_exit();
yield();
}
return;
}
if(v == (IRQ_OFFSET + IRQ_IDE)){
ide_intr();
return;
}
// XXX probably ought to lgdt on trap return
return;
}
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