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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];
extern uint vectors[]; /* vectors.S, array of 256 entry point addresses */
extern void trapenter(void);
extern void trapenter1(void);
void
tvinit(void)
{
int i;
for(i = 0; i < 256; i++){
SETGATE(idt[i], 1, SEG_KCODE << 3, vectors[i], 0);
}
SETGATE(idt[T_SYSCALL], 1, SEG_KCODE << 3, vectors[48], 3);
}
void
idtinit(void)
{
lidt(idt, sizeof idt);
}
void
trap(struct trapframe *tf)
{
int v = tf->trapno;
if(v == T_SYSCALL){
struct proc *cp = curproc[cpu()];
if(cp->killed)
proc_exit();
cp->tf = tf;
syscall();
if(cp->killed)
proc_exit();
return;
}
if(v == (IRQ_OFFSET + IRQ_TIMER)){
struct proc *cp = curproc[cpu()];
lapic_timerintr();
if(cp){
// Force process exit if it has been killed
// and the interrupt came from user space.
// (If the kernel was executing at time of interrupt,
// don't kill the process. Let the process get back
// out to its regular system call return.)
if((tf->cs&3) == 3 && cp->killed)
proc_exit();
// Force process to give up CPU and let others run.
if(cp->state == RUNNING)
yield();
}
return;
}
if(v == (IRQ_OFFSET + IRQ_IDE)){
ide_intr();
cli(); // prevent a waiting interrupt from overflowing stack
lapic_eoi();
return;
}
if(v == (IRQ_OFFSET + IRQ_KBD)){
kbd_intr();
cli(); // prevent a waiting interrupt from overflowing stack
lapic_eoi();
return;
}
if(v == (IRQ_OFFSET + IRQ_SPURIOUS)){
cprintf("spurious interrupt from cpu %d eip %x\n", cpu(), tf->eip);
return; // no eoi for this one.
}
if(curproc[cpu()]) {
cprintf("pid %d: unhandled trap %d on cpu %d eip %x---terminate process\n",
curproc[cpu()]->pid, v, cpu(), tf->eip);
proc_exit();
}
cprintf("unexpected trap %d from cpu %d eip %x\n", v, cpu(), tf->eip);
panic("trap");
}
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