metal-cos/sys/amd64/trap.c

285 lines
6.3 KiB
C

#include <stdbool.h>
#include <stdint.h>
#include <sys/kconfig.h>
#include <sys/kassert.h>
#include <sys/kdebug.h>
#include <sys/kmem.h>
#include <sys/ktime.h>
#include <sys/spinlock.h>
#include <sys/irq.h>
#include <sys/syscall.h>
#include <sys/mp.h>
#include <machine/amd64.h>
#include <machine/lapic.h>
#include <machine/trap.h>
#include <machine/mp.h>
#include <sys/thread.h>
extern uint64_t trap_table[T_MAX];
extern void trap_pop(TrapFrame *tf);
extern void Debug_Breakpoint(TrapFrame *tf);
extern void Debug_HaltIPI(TrapFrame *tf);
extern void KTimer_Process();
static InteruptGate64 idt[256];
static PseudoDescriptor idtdesc;
static uint64_t intStats[256];
void
Trap_Init()
{
int i;
kprintf("Initializing IDT... ");
for (i = 0; i < T_MAX; i++) {
idt[i].pc_low = trap_table[i] & 0x0000ffff;
idt[i].pc_mid = (trap_table[i] >> 16) & 0x0000ffff;
idt[i].pc_high = trap_table[i] >> 32;
idt[i].cs = 0x0008;
idt[i].type = 0x8E;
idt[i].ist = 0x00;
idt[i]._unused1 = 0x00000000;
}
for (; i < 256; i++) {
idt[i].pc_low = trap_table[63] & 0x0000ffff;
idt[i].pc_mid = (trap_table[63] >> 16) & 0x0000ffff;
idt[i].pc_high = trap_table[63] >> 32;
idt[i].cs = 0x0008;
idt[i].type = 0x8E;
idt[i].ist = 0;
idt[i]._unused1 = 0;
}
// Double fault handler
idt[T_NMI].ist = 0x01;
idt[T_DF].ist = 0x01;
idt[T_GP].ist = 0x01;
idt[T_NP].ist = 0x01;
idt[T_SS].ist = 0x01;
// Enable Breakpoint and Syscall from Userspace
idt[T_DB].type = 0xEE;
idt[T_BP].type = 0xEE;
idt[T_SYSCALL].type = 0xEE;
idtdesc.off = (uint64_t)&idt;
idtdesc.lim = sizeof(idt) - 1;
lidt(&idtdesc);
// Zero out interrupt stats
for (i = 0; i < 256; i++) {
intStats[i] = 0;
}
kprintf("Done!\n");
}
void
Trap_InitAP()
{
lidt(&idtdesc);
}
void
Trap_Dump(TrapFrame *tf)
{
kprintf("CPU %d\n", CPU());
kprintf("Interrupt %d Error Code: %016llx\n",
tf->vector, tf->errcode);
kprintf("cr0: %016llx cr2: %016llx\n",
read_cr0(), read_cr2());
kprintf("cr3: %016llx cr4: %016llx\n",
read_cr3(), read_cr4());
kprintf("dr0: %016llx dr1: %016llx dr2: %016llx\n",
read_dr0(), read_dr1(), read_dr2());
kprintf("dr3: %016llx dr6: %016llx dr7: %016llx\n",
read_dr3(), read_dr6(), read_dr7());
kprintf("rip: %04x:%016llx rsp: %04x:%016llx\n",
tf->cs, tf->rip, tf->ss, tf->rsp);
kprintf("rflags: %016llx ds: %04x es: %04x fs: %04x gs: %04x\n",
tf->rflags, read_ds(), read_es(), read_fs(), read_gs());
kprintf("rax: %016llx rbx: %016llx rcx: %016llx\n",
tf->rax, tf->rbx, tf->rcx);
kprintf("rdx: %016llx rsi: %016llx rdi: %016llx\n",
tf->rdx, tf->rsi, tf->rdi);
kprintf("rbp: %016llx r8: %016llx r9: %016llx\n",
tf->rbp, tf->r8, tf->r9);
kprintf("r10: %016llx r11: %016llx r12: %016llx\n",
tf->r10, tf->r11, tf->r12);
kprintf("r13: %016llx r14: %016llx r15: %016llx\n",
tf->r13, tf->r14, tf->r15);
}
void
Trap_StackDump(TrapFrame *tf)
{
uint64_t rsp;
uint64_t *data;
// XXX: This should use safe copy
for (rsp = tf->rsp; (rsp & 0xFFF) != 0; rsp += 8) {
data = (uint64_t *)rsp;
kprintf("%016llx: %016llx\n", rsp, *data);
}
}
extern int copy_unsafe(void *to, void *from, uintptr_t len);
extern void copy_unsafe_done(void);
extern void copy_unsafe_fault(void);
extern int copystr_unsafe(void *to, void *from, uintptr_t len);
extern void copystr_unsafe_done(void);
extern void copystr_unsafe_fault(void);
void
trap_entry(TrapFrame *tf)
{
// XXX: USE ATOMIC!
intStats[tf->vector]++;
// Debug NMI (should be T_DEBUGIPI)
if (tf->vector == T_NMI) {
Debug_HaltIPI(tf);
LAPIC_SendEOI();
return;
}
// Kernel
if (tf->cs == SEL_KCS)
{
// Kernel Debugger
if (tf->vector == T_BP || tf->vector == T_DE) {
Debug_Breakpoint(tf);
return;
}
// User IO
if ((tf->vector == T_PF) &&
(tf->rip >= (uint64_t)&copy_unsafe) &&
(tf->rip <= (uint64_t)&copy_unsafe_done)) {
kprintf("Faulted in copy_unsafe\n");
tf->rip = (uint64_t)&copy_unsafe_fault;
return;
}
// User IO
if ((tf->vector == T_PF) &&
(tf->rip >= (uint64_t)&copystr_unsafe) &&
(tf->rip <= (uint64_t)&copystr_unsafe_done)) {
kprintf("Faulted in copystr_unsafe\n");
tf->rip = (uint64_t)&copystr_unsafe_fault;
return;
}
// Halt on kernel errors
if (tf->vector <= T_CPU_LAST)
{
Critical_Enter();
kprintf("Kernel Fault: Vector %d\n", tf->vector);
Trap_Dump(tf);
Debug_Breakpoint(tf);
while (1)
hlt();
}
}
// User space exceptions
switch (tf->vector)
{
case T_DE:
kprintf("Divide by Zero\n");
return;
case T_DB:
case T_BP:
case T_UD: {
kprintf("Userlevel breakpoint\n");
Debug_Breakpoint(tf);
return;
}
case T_PF: {
Trap_Dump(tf);
Trap_StackDump(tf);
Debug_Breakpoint(tf);
}
case T_SYSCALL: {
VLOG(syscall, "Syscall %016llx\n", tf->rdi);
tf->rax = Syscall_Entry(tf->rdi, tf->rsi, tf->rdx, tf->rcx, tf->r8, tf->r9);
VLOG(syscall, "Return %016llx\n", tf->rax);
return;
}
}
// IRQs
if (tf->vector >= T_IRQ_BASE && tf->vector <= T_IRQ_MAX)
{
LAPIC_SendEOI();
IRQ_Handler(tf->vector - T_IRQ_BASE);
if (tf->vector == T_IRQ_TIMER) {
KTimer_Process();
Sched_Scheduler();
}
return;
}
// Cross calls
if (tf->vector == T_CROSSCALL)
{
MP_CrossCallTrap();
LAPIC_SendEOI();
return;
}
// LAPIC Special Vectors
if (tf->vector == T_IRQ_SPURIOUS)
{
kprintf("Spurious Interrupt!\n");
return;
}
if (tf->vector == T_IRQ_ERROR)
{
kprintf("LAPIC Error!\n");
while (1)
hlt();
}
if (tf->vector == T_IRQ_THERMAL)
{
kprintf("Thermal Error!\n");
while (1)
hlt();
}
kprintf("Unhandled Interrupt 0x%x!\n", tf->vector);
Trap_Dump(tf);
while (1)
hlt();
}
static void
Debug_Traps(int argc, const char *argv[])
{
int i;
kprintf("Trap Interrupts Trap Interrupts\n");
for (i = 0; i < T_MAX / 2; i++)
{
kprintf("%-4d %-12d %-4d %-12d\n",
i, intStats[i],
T_MAX / 2 + i, intStats[T_MAX / 2 + i]);
}
}
REGISTER_DBGCMD(traps, "Print trap statistics", Debug_Traps);