minix/kernel/arch/i386/exception.c
Ben Gras 6f77685609 Split of architecture-dependent and -independent functions for i386,
mainly in the kernel and headers. This split based on work by
Ingmar Alting <iaalting@cs.vu.nl> done for his Minix PowerPC architecture
port.

 . kernel does not program the interrupt controller directly, do any
   other architecture-dependent operations, or contain assembly any more,
   but uses architecture-dependent functions in arch/$(ARCH)/.
 . architecture-dependent constants and types defined in arch/$(ARCH)/include.
 . <ibm/portio.h> moved to <minix/portio.h>, as they have become, for now,
   architecture-independent functions.
 . int86, sdevio, readbios, and iopenable are now i386-specific kernel calls
   and live in arch/i386/do_* now.
 . i386 arch now supports even less 86 code; e.g. mpx86.s and klib86.s have
   gone, and 'machine.protected' is gone (and always taken to be 1 in i386).
   If 86 support is to return, it should be a new architecture.
 . prototypes for the architecture-dependent functions defined in
   kernel/arch/$(ARCH)/*.c but used in kernel/ are in kernel/proto.h
 . /etc/make.conf included in makefiles and shell scripts that need to
   know the building architecture; it defines ARCH=<arch>, currently only
   i386.
 . some basic per-architecture build support outside of the kernel (lib)
 . in clock.c, only dequeue a process if it was ready
 . fixes for new include files

files deleted:
 . mpx/klib.s - only for choosing between mpx/klib86 and -386
 . klib86.s - only for 86

i386-specific files files moved (or arch-dependent stuff moved) to arch/i386/:
 . mpx386.s (entry point)
 . klib386.s
 . sconst.h
 . exception.c
 . protect.c
 . protect.h
 . i8269.c
2006-12-22 15:22:27 +00:00

121 lines
3.4 KiB
C
Executable file

/* This file contains a simple exception handler. Exceptions in user
* processes are converted to signals. Exceptions in a kernel task cause
* a panic.
*/
#include "../../kernel.h"
#include <signal.h>
#include "../../proc.h"
/*===========================================================================*
* exception *
*===========================================================================*/
PUBLIC void exception(unsigned vec_nr)
{
/* An exception or unexpected interrupt has occurred. */
struct ex_s {
char *msg;
int signum;
int minprocessor;
};
static struct ex_s ex_data[] = {
{ "Divide error", SIGFPE, 86 },
{ "Debug exception", SIGTRAP, 86 },
{ "Nonmaskable interrupt", SIGBUS, 86 },
{ "Breakpoint", SIGEMT, 86 },
{ "Overflow", SIGFPE, 86 },
{ "Bounds check", SIGFPE, 186 },
{ "Invalid opcode", SIGILL, 186 },
{ "Coprocessor not available", SIGFPE, 186 },
{ "Double fault", SIGBUS, 286 },
{ "Copressor segment overrun", SIGSEGV, 286 },
{ "Invalid TSS", SIGSEGV, 286 },
{ "Segment not present", SIGSEGV, 286 },
{ "Stack exception", SIGSEGV, 286 }, /* STACK_FAULT already used */
{ "General protection", SIGSEGV, 286 },
{ "Page fault", SIGSEGV, 386 }, /* not close */
{ NIL_PTR, SIGILL, 0 }, /* probably software trap */
{ "Coprocessor error", SIGFPE, 386 },
};
register struct ex_s *ep;
struct proc *saved_proc;
/* Save proc_ptr, because it may be changed by debug statements. */
saved_proc = proc_ptr;
ep = &ex_data[vec_nr];
if (vec_nr == 2) { /* spurious NMI on some machines */
kprintf("got spurious NMI\n");
return;
}
/* If an exception occurs while running a process, the k_reenter variable
* will be zero. Exceptions in interrupt handlers or system traps will make
* k_reenter larger than zero.
*/
if (k_reenter == 0 && ! iskernelp(saved_proc)) {
#if 0
{
kprintf(
"exception for process %d, pc = 0x%x:0x%x, sp = 0x%x:0x%x\n",
proc_nr(saved_proc),
saved_proc->p_reg.cs, saved_proc->p_reg.pc,
saved_proc->p_reg.ss, saved_proc->p_reg.sp);
kprintf("edi = 0x%x\n", saved_proc->p_reg.di);
#if DEBUG_STACKTRACE
stacktrace(saved_proc);
#endif
}
#endif
cause_sig(proc_nr(saved_proc), ep->signum);
return;
}
/* Exception in system code. This is not supposed to happen. */
if (ep->msg == NIL_PTR || machine.processor < ep->minprocessor)
kprintf("\nIntel-reserved exception %d\n", vec_nr);
else
kprintf("\n%s\n", ep->msg);
kprintf("k_reenter = %d ", k_reenter);
kprintf("process %d (%s), ", proc_nr(saved_proc), saved_proc->p_name);
kprintf("pc = %u:0x%x", (unsigned) saved_proc->p_reg.cs,
(unsigned) saved_proc->p_reg.pc);
panic("exception in a kernel task", NO_NUM);
}
#if DEBUG_STACKTRACE
/*===========================================================================*
* stacktrace *
*===========================================================================*/
PUBLIC void stacktrace(struct proc *proc)
{
reg_t bp, v_bp, v_pc, v_hbp;
v_bp = proc->p_reg.fp;
kprintf("stacktrace: ");
while(v_bp) {
phys_bytes p;
if(!(p = umap_local(proc, D, v_bp, sizeof(v_bp)))) {
kprintf("(bad bp %lx)", v_bp);
break;
}
phys_copy(p+sizeof(v_pc), vir2phys(&v_pc), sizeof(v_pc));
phys_copy(p, vir2phys(&v_hbp), sizeof(v_hbp));
kprintf("0x%lx ", (unsigned long) v_pc);
if(v_hbp != 0 && v_hbp <= v_bp) {
kprintf("(bad hbp %lx)", v_hbp);
break;
}
v_bp = v_hbp;
}
kprintf("\n");
}
#endif