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/*
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
* Copyright (C) 1995, 1996 TooLs GmbH.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $NetBSD: trap.c,v 1.26 2000/05/27 00:40:40 sommerfeld Exp $
*/
#ifndef lint
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include "opt_ddb.h"
#include "opt_ktrace.h"
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/ktr.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/pioctl.h>
#include <sys/reboot.h>
#include <sys/syscall.h>
#include <sys/sysent.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <sys/user.h>
#ifdef KTRACE
#include <sys/ktrace.h>
#endif
#include <sys/vmmeter.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_extern.h>
#include <vm/vm_kern.h>
#include <vm/vm_map.h>
#include <vm/vm_param.h>
#include <machine/cpu.h>
#include <machine/frame.h>
#include <machine/pcb.h>
#include <machine/psl.h>
#include <machine/trap.h>
/* These definitions should probably be somewhere else XXX */
#define FIRSTARG 3 /* first argument is in reg 3 */
#define NARGREG 8 /* 8 args are in registers */
#define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */
#ifdef WITNESS
extern char *syscallnames[];
#endif
#if 0 /* XXX: not used yet */
static int fix_unaligned(struct proc *p, struct trapframe *frame);
#endif
static void trap_fatal(struct trapframe *frame);
static void printtrap(int vector, struct trapframe *frame, int isfatal,
int user);
static int trap_pfault(struct trapframe *frame, int user);
static int handle_onfault (struct trapframe *frame);
static const char *ppc_exception_names[] = {
"reserved 0", /* 0 */
"reset", /* 1 */
"machine check", /* 2 */
"data storage interrupt", /* 3 */
"instruction storage interrupt", /* 4 */
"external interrupt", /* 5 */
"alignment interrupt", /* 6 */
"program interrupt", /* 7 */
"floating point unavailable", /* 8 */
"decrementer interrupt", /* 9 */
"reserved", /* 10 */
"reserved", /* 11 */
"system call", /* 12 */
"trace", /* 13 */
"floating point assist", /* 14 */
"performance monitoring", /* 15 */
"instruction tlb miss", /* 16 */
"data load tlb miss", /* 17 */
"data store tlb miss", /* 18 */
"instruction breakpoint", /* 19 */
"system management interrupt", /* 20 */
"reserved 21", /* 21 */
"reserved 22", /* 22 */
"reserved 23", /* 23 */
"reserved 24", /* 24 */
"reserved 25", /* 25 */
"reserved 26", /* 26 */
"reserved 27", /* 27 */
"reserved 28", /* 28 */
"reserved 29", /* 29 */
"reserved 30", /* 30 */
"reserved 31", /* 31 */
"reserved 32", /* 32 */
"reserved 33", /* 33 */
"reserved 34", /* 34 */
"reserved 35", /* 35 */
"reserved 36", /* 36 */
"reserved 37", /* 37 */
"reserved 38", /* 38 */
"reserved 39", /* 39 */
"reserved 40", /* 40 */
"reserved 41", /* 41 */
"reserved 42", /* 42 */
"reserved 43", /* 43 */
"reserved 44", /* 44 */
"reserved 45", /* 45 */
"reserved 46", /* 46 */
"reserved 47", /* 47 */
};
static void
printtrap(int vector, struct trapframe *frame, int isfatal, int user)
{
printf("\n");
printf("%s %s trap:\n", isfatal ? "fatal" : "handled",
user ? "user" : "kernel");
printf("\n");
printf(" exception = 0x%x (%s)\n", vector >> 8,
ppc_exception_names[vector >> 8]);
switch (vector) {
case EXC_DSI:
printf(" virtual address = 0x%x\n", frame->dar);
break;
case EXC_ISI:
printf(" virtual address = 0x%x\n", frame->srr0);
break;
}
printf(" srr0 = 0x%x", frame->srr0);
printf(" curthread = %p\n", curthread);
if (curthread != NULL)
printf(" pid = %d, comm = %s\n",
curthread->td_proc->p_pid, curthread->td_proc->p_comm);
printf("\n");
}
static void
trap_fatal(struct trapframe *frame)
{
printtrap(frame->exc, frame, 1, (frame->srr1 & PSL_PR));
#ifdef DDB
if ((debugger_on_panic || db_active) && kdb_trap(frame->exc, 0, frame))
return;
#endif
panic("%s Trap", ppc_exception_names[frame->exc >> 8]);
}
/*
* Handles a fatal fault when we have onfault state to recover. Returns
* non-zero if there was onfault recovery state available.
*/
static int
handle_onfault (struct trapframe *frame)
{
struct thread *td;
faultbuf *fb;
td = curthread;
fb = td->td_pcb->pcb_onfault;
if (fb != NULL) {
frame->srr0 = (*fb)[0];
frame->fixreg[1] = (*fb)[1];
frame->fixreg[2] = (*fb)[2];
frame->cr = (*fb)[3];
bcopy(&(*fb)[4], &frame->fixreg[13],
19 * sizeof(register_t));
return (1);
}
return (0);
}
void
trap(struct trapframe *frame)
{
struct thread *td;
struct proc *p;
int sig, type, user;
u_int sticks, ucode;
atomic_add_int(&cnt.v_trap, 1);
td = curthread;
p = td->td_proc;
type = frame->exc;
ucode = type;
sig = 0;
user = (frame->srr1 & PSL_PR);
sticks = 0;
CTR3(KTR_TRAP, "trap: %s type=%s (%s)", p->p_comm,
ppc_exception_names[type >> 8],
user ? "user" : "kernel");
if (user) {
sticks = td->td_kse->ke_sticks;
td->td_frame = frame;
if (td->td_ucred != p->p_ucred)
cred_update_thread(td);
/* User Mode Traps */
switch (type) {
case EXC_TRC:
frame->srr1 &= ~PSL_SE;
sig = SIGTRAP;
break;
case EXC_DSI:
case EXC_ISI:
sig = trap_pfault(frame, 1);
break;
case EXC_SC:
syscall(frame);
break;
case EXC_FPU:
enable_fpu(PCPU_GET(curpcb));
frame->srr1 |= PSL_FP;
break;
case EXC_ALI:
#if 0
if (fix_unaligned(p, frame) != 0)
#endif
sig = SIGBUS;
#if 0
else
frame->srr0 += 4;
#endif
break;
case EXC_PGM:
/* XXX temporarily */
/* XXX: Magic Number? */
if (frame->srr1 & 0x0002000)
sig = SIGTRAP;
else
sig = SIGILL;
break;
default:
trap_fatal(frame);
}
} else {
/* Kernel Mode Traps */
KASSERT(cold || td->td_ucred != NULL,
("kernel trap doesn't have ucred"));
switch (type) {
case EXC_DSI:
if (trap_pfault(frame, 0) == 0)
return;
break;
case EXC_MCHK:
if (handle_onfault(frame))
return;
break;
default:
trap_fatal(frame);
}
/* NOTREACHED */
}
if (sig != 0) {
if (p->p_sysent->sv_transtrap != NULL)
sig = (p->p_sysent->sv_transtrap)(sig, type);
trapsignal(p, sig, ucode);
}
userret(td, frame, sticks);
mtx_assert(&Giant, MA_NOTOWNED);
#ifdef DIAGNOSTIC
cred_free_thread(td);
#endif
}
void
syscall(struct trapframe *frame)
{
caddr_t params;
struct sysent *callp;
struct thread *td;
struct proc *p;
int error, n;
size_t narg;
register_t args[10];
u_int code;
td = curthread;
p = td->td_proc;
atomic_add_int(&cnt.v_syscall, 1);
code = frame->fixreg[0];
params = (caddr_t) (frame->fixreg + FIRSTARG);
if (p->p_sysent->sv_prepsyscall)
/*
* The prep code is MP aware.
*/
(*p->p_sysent->sv_prepsyscall)(frame, args, &code, ¶ms);
else if (code == SYS_syscall)
/*
* code is first argument,
* followed by actual args.
*/
code = *params++;
else if (code == SYS___syscall) {
/*
* Like syscall, but code is a quad,
* so as to maintain quad alignment
* for the rest of the args.
*/
params++;
code = *params++;
}
if (p->p_sysent->sv_mask)
code &= p->p_sysent->sv_mask;
if (code >= p->p_sysent->sv_size)
callp = &p->p_sysent->sv_table[0];
else
callp = &p->p_sysent->sv_table[code];
narg = callp->sy_narg & SYF_ARGMASK;
n = NARGREG - (params - (caddr_t)(frame->fixreg + FIRSTARG));
if (narg > n * sizeof(register_t)) {
bcopy(params, args, n * sizeof(register_t));
if (error = copyin(MOREARGS(frame->fixreg[1]), args + n,
narg - n * sizeof(register_t))) {
#ifdef KTRACE
/* Can't get all the arguments! */
if (KTRPOINT(p, KTR_SYSCALL))
ktrsyscall(p->p_tracep, code, narg, args);
#endif
goto bad;
}
params = (caddr_t) args;
}
/*
* Try to run the syscall without Giant if the syscall is MP safe.
*/
if ((callp->sy_narg & SYF_MPSAFE) == 0)
mtx_lock(&Giant);
#ifdef KTRACE
if (KTRPOINT(p, KTR_SYSCALL))
ktrsyscall(p->p_tracep, code, narg, params);
#endif
td->td_retval[0] = 0;
td->td_retval[1] = frame->fixreg[FIRSTARG + 1];
STOPEVENT(p, S_SCE, narg);
error = (*callp->sy_call)(td, args);
switch (error) {
case 0:
frame->fixreg[FIRSTARG] = td->td_retval[0];
frame->fixreg[FIRSTARG + 1] = td->td_retval[1];
/* XXX: Magic number */
frame->cr &= ~0x10000000;
break;
case ERESTART:
/*
* Set user's pc back to redo the system call.
*/
frame->srr0 -= 4;
break;
case EJUSTRETURN:
/* nothing to do */
break;
default:
bad:
if (p->p_sysent->sv_errsize) {
if (error >= p->p_sysent->sv_errsize)
error = -1; /* XXX */
else
error = p->p_sysent->sv_errtbl[error];
}
frame->fixreg[FIRSTARG] = error;
/* XXX: Magic number: Carry Flag Equivalent? */
frame->cr |= 0x10000000;
break;
}
#ifdef KTRACE
if (KTRPOINT(p, KTR_SYSRET))
ktrsysret(p->p_tracep, code, error, td->td_retval[0]);
#endif
if ((callp->sy_narg & SYF_MPSAFE) == 0)
mtx_unlock(&Giant);
/*
* Does the comment in the i386 code about errno apply here?
*/
STOPEVENT(p, S_SCX, code);
#ifdef WITNESS
if (witness_list(td)) {
panic("system call %s returning with mutex(s) held\n",
syscallnames[code]);
}
#endif
mtx_assert(&sched_lock, MA_NOTOWNED);
mtx_assert(&Giant, MA_NOTOWNED);
}
static int
trap_pfault(struct trapframe *frame, int user)
{
vm_offset_t eva, va;
struct thread *td;
struct proc *p;
vm_map_t map;
vm_prot_t ftype;
int rv;
td = curthread;
p = td->td_proc;
if (frame->exc == EXC_ISI) {
eva = frame->srr0;
ftype = VM_PROT_READ | VM_PROT_EXECUTE;
} else {
eva = frame->dar;
if (frame->dsisr & DSISR_STORE)
ftype = VM_PROT_READ | VM_PROT_WRITE;
else
ftype = VM_PROT_READ;
}
if ((eva >> ADDR_SR_SHFT) != USER_SR) {
if (user)
return (SIGSEGV);
map = kernel_map;
} else {
u_int user_sr;
if (p->p_vmspace == NULL)
return (SIGSEGV);
__asm ("mfsr %0, %1"
: "=r"(user_sr)
: "K"(USER_SR));
eva &= ADDR_PIDX | ADDR_POFF;
eva |= user_sr << ADDR_SR_SHFT;
map = &p->p_vmspace->vm_map;
}
va = trunc_page(eva);
if (map != kernel_map) {
/*
* Keep swapout from messing with us during this
* critical time.
*/
PROC_LOCK(p);
++p->p_lock;
PROC_UNLOCK(p);
/* Fault in the user page: */
rv = vm_fault(map, va, ftype,
(ftype & VM_PROT_WRITE) ? VM_FAULT_DIRTY
: VM_FAULT_NORMAL);
PROC_LOCK(p);
--p->p_lock;
PROC_UNLOCK(p);
} else {
/*
* Don't have to worry about process locking or stacks in the
* kernel.
*/
rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL);
}
if (rv == KERN_SUCCESS)
return (0);
if (!user && handle_onfault(frame))
return (0);
return (SIGSEGV);
}
#if 0 /* XXX: child_return not used */
/*
* XXX: the trapframe return values should be setup in vm_machdep.c in
* cpu_fork().
*/
void
child_return(void *arg)
{
struct proc *p;
struct trapframe *tf;
p = arg;
tf = trapframe(p);
tf->fixreg[FIRSTARG] = 0;
tf->fixreg[FIRSTARG + 1] = 1;
tf->cr &= ~0x10000000;
tf->srr1 &= ~PSL_FP; /* Disable FPU, as we can't be fpuproc */
#ifdef KTRACE
if (KTRPOINT(p, KTR_SYSRET))
ktrsysret(p, SYS_fork, 0, 0);
#endif
/* Profiling? XXX */
curcpu()->ci_schedstate.spc_curpriority = p->p_priority;
}
#endif
#if 0 /* XXX: not used yet */
/*
* kcopy(const void *src, void *dst, size_t len);
*
* Copy len bytes from src to dst, aborting if we encounter a fatal
* page fault.
*
* kcopy() _must_ save and restore the old fault handler since it is
* called by uiomove(), which may be in the path of servicing a non-fatal
* page fault.
*/
int
kcopy(const void *src, void *dst, size_t len)
{
faultbuf env, *oldfault;
oldfault = PCPU_GET(curpcb)->pcb_onfault;
if (setfault(env)) {
PCPU_GET(curpcb)->pcb_onfault = oldfault;
return EFAULT;
}
bcopy(src, dst, len);
PCPU_GET(curpcb)->pcb_onfault = oldfault;
return 0;
}
int
badaddr(void *addr, size_t size)
{
return badaddr_read(addr, size, NULL);
}
int
badaddr_read(void *addr, size_t size, int *rptr)
{
faultbuf env;
int x;
/* Get rid of any stale machine checks that have been waiting. */
__asm __volatile ("sync; isync");
if (setfault(env)) {
PCPU_GET(curpcb)->pcb_onfault = 0;
__asm __volatile ("sync");
return 1;
}
__asm __volatile ("sync");
switch (size) {
case 1:
x = *(volatile int8_t *)addr;
break;
case 2:
x = *(volatile int16_t *)addr;
break;
case 4:
x = *(volatile int32_t *)addr;
break;
default:
panic("badaddr: invalid size (%d)", size);
}
/* Make sure we took the machine check, if we caused one. */
__asm __volatile ("sync; isync");
PCPU_GET(curpcb)->pcb_onfault = 0;
__asm __volatile ("sync"); /* To be sure. */
/* Use the value to avoid reorder. */
if (rptr)
*rptr = x;
return 0;
}
#endif
/*
* For now, this only deals with the particular unaligned access case
* that gcc tends to generate. Eventually it should handle all of the
* possibilities that can happen on a 32-bit PowerPC in big-endian mode.
*/
#if 0 /* XXX: Not used yet */
static int
fix_unaligned(p, frame)
struct proc *p;
struct trapframe *frame;
{
int indicator;
indicator = EXC_ALI_OPCODE_INDICATOR(frame->dsisr);
switch (indicator) {
case EXC_ALI_LFD:
case EXC_ALI_STFD:
{
int reg = EXC_ALI_RST(frame->dsisr);
double *fpr = &p->p_addr->u_pcb.pcb_fpu.fpr[reg];
/* Juggle the FPU to ensure that we've initialized
* the FPRs, and that their current state is in
* the PCB.
*/
if (!(pcb->pcb_flags & PCB_FPU))
enable_fpu(PCPU_GET(curpcb));
frame->srr1 |= PSL_FP;
}
save_fpu(PCPU_GET(curpcb));
if (indicator == EXC_ALI_LFD) {
if (copyin((void *)frame->dar, fpr,
sizeof(double)) != 0)
return -1;
if (!(pcb->pcb_flags & PCB_FPU))
enable_fpu(PCPU_GET(curpcb));
frame->srr1 |= PSL_FP;
}
} else {
if (copyout(fpr, (void *)frame->dar,
sizeof(double)) != 0)
return -1;
}
return 0;
}
break;
}
return -1;
}
#endif
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