ref: a7b1ab8236b7ccd41e96e9e4008cbc3213294724
dir: /trap.c/
#include "u.h"
#include <ureg.h>
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "../port/error.h"
#include "tos.h"
static void
_dumpstack(Ureg *ureg)
{
uintptr l, v, i, estack;
extern ulong etext;
int x;
char *s;
iprint("%s", "DUMP STACK\n");
if((s = getconf("*nodumpstack")) != nil && strcmp(s, "0") != 0){
iprint("dumpstack disabled\n");
return;
}
iprint("cpu%d: dumpstack\n", m->machno);
x = 0;
x += iprint("ktrace /arm/9bbb %.8lux %.8lux %.8lux <<EOF\n", ureg->pc, ureg->sp, ureg->r14);
i = 0;
if(up
&& (uintptr)&l >= (uintptr)up->kstack
&& (uintptr)&l <= (uintptr)up->kstack+KSTACK)
estack = (uintptr)up->kstack+KSTACK;
else if((uintptr)&l >= (uintptr)m->stack
&& (uintptr)&l <= (uintptr)m+MACHSIZE)
estack = (uintptr)m+MACHSIZE;
else
return;
x += iprint("estackx %p\n", estack);
for(l = (uintptr)&l; l < estack; l += sizeof(uintptr)){
v = *(uintptr*)l;
if((KTZERO < v && v < (uintptr)&etext) || estack-l < 32){
x += iprint("%.8p=%.8p ", l, v);
i++;
}
if(i == 4){
i = 0;
x += iprint("\n");
}
}
if(i)
iprint("\n");
iprint("EOF\n");
}
static char*
faulterr[0x20] = {
[0x01] "alignement fault",
[0x02] "debug event",
[0x04] "fault on instruction cache maintenance",
[0x08] "synchronous external abort",
[0x0C] "synchronous external abort on translation table walk L1",
[0x0E] "synchronous external abort on translation table walk L2",
[0x10] "tlb conflict abort",
[0x16] "asynchronous external abort",
[0x19] "synchronous parity error on memory access",
[0x1C] "synchronous parity error on translation table walk L1",
[0x1E] "synchronous parity error on translation table walk L2",
};
static void
faultarm(Ureg *ureg, ulong fsr, uintptr addr)
{
int user, insyscall, read;
static char buf[ERRMAX];
char *err;
read = (fsr & (1<<11)) == 0;
user = userureg(ureg);
if(!user){
if(addr >= USTKTOP || up == nil)
_dumpstack(ureg);
if(addr >= USTKTOP)
panic("kernel fault: bad address pc=%#.8lux addr=%#.8lux fsr=%#.8lux", ureg->pc, addr, fsr);
if(up == nil)
panic("kernel fault: no user process pc=%#.8lux addr=%#.8lux fsr=%#.8lux", ureg->pc, addr, fsr);
}
if(up == nil)
panic("user fault: up=nil pc=%#.8lux addr=%#.8lux fsr=%#.8lux", ureg->pc, addr, fsr);
insyscall = up->insyscall;
up->insyscall = 1;
switch(fsr & 0x1F){
case 0x05: /* translation fault L1 */
case 0x07: /* translation fault L2 */
case 0x03: /* access flag fault L1 */
case 0x06: /* access flag fault L2 */
case 0x09: /* domain fault L1 */
case 0x0B: /* domain fault L2 */
case 0x0D: /* permission fault L1 */
case 0x0F: /* permission fault L2 */
//iprint("fsr=%08x, addr=%#p, read=%d\n", fsr&0x1f, addr, read);
if(fault(addr, read) == 0)
break;
//iprint("wet floor\n");
/* wet floor */
default:
err = faulterr[fsr & 0x1F];
if(err == nil)
err = "fault";
if(!user){
dumpregs(ureg);
_dumpstack(ureg);
panic("kernel %s: pc=%#.8lux addr=%#.8lux fsr=%#.8lux", err, ureg->pc, addr, fsr);
}
sprint(buf, "sys: trap: %s %s addr=%#.8lux", err, read ? "read" : "write", addr);
print("%s\n", buf);
postnote(up, 1, buf, NDebug);
}
up->insyscall = insyscall;
}
static void
mathtrap(Ureg *, ulong)
{
int s;
if((up->fpstate & FPillegal) != 0){
postnote(up, 1, "sys: floating point in note handler", NDebug);
return;
}
switch(up->fpstate){
case FPinit:
s = splhi();
fpinit();
up->fpstate = FPactive;
splx(s);
break;
case FPinactive:
s = splhi();
fprestore(up->fpsave);
up->fpstate = FPactive;
splx(s);
break;
case FPactive:
postnote(up, 1, "sys: floating point error", NDebug);
break;
}
}
void vectors(void);
void
trap(Ureg *ureg)
{
int user;
ulong opc, cp;
user = userureg(ureg);
if(user){
if(up == nil)
panic("user trap: up=nil");
up->dbgreg = ureg;
cycles(&up->kentry);
}
switch(ureg->type){
case PsrMund:
ureg->pc -= 4;
if(user){
spllo();
if(okaddr(ureg->pc, 4, 0)){
opc = *(ulong*)ureg->pc;
if((opc & 0x0f000000) == 0x0e000000 || (opc & 0x0e000000) == 0x0c000000){
cp = opc >> 8 & 15;
if(cp == 10 || cp == 11){
mathtrap(ureg, opc);
break;
}
}
}
postnote(up, 1, "sys: trap: invalid opcode", NDebug);
break;
}
dumpregs(ureg);
panic("invalid opcode at pc=%#.8lux lr=%#.8lux", ureg->pc, ureg->r14);
break;
case PsrMiabt:
ureg->pc -= 4;
faultarm(ureg, getifsr(), getifar());
break;
case PsrMabt:
ureg->pc -= 8;
faultarm(ureg, getdfsr(), getdfar());
break;
case PsrMirq:
ureg->pc -= 4;
intr(ureg);
break;
default:
iprint("cpu%d: unknown trap type %ulx\n", m->machno, ureg->type);
}
splhi();
if(user){
if(up->procctl || up->nnote)
notify(ureg);
kexit(ureg);
}
}
#include "../port/systab.h"
void
syscall(Ureg *ureg)
{
char *e;
uintptr sp;
long ret;
int i, s;
ulong scallnr;
vlong startns, stopns;
if(!userureg(ureg))
panic("syscall: pc=%#.8lux", ureg->pc);
cycles(&up->kentry);
m->syscall++;
up->insyscall = 1;
up->pc = ureg->pc;
up->dbgreg = ureg;
sp = ureg->sp;
up->scallnr = scallnr = ureg->r0;
spllo();
up->nerrlab = 0;
ret = -1;
if(!waserror()){
if(sp < USTKTOP - BY2PG || sp > USTKTOP - sizeof(Sargs) - BY2WD){
validaddr(sp, sizeof(Sargs)+BY2WD, 0);
evenaddr(sp);
}
up->s = *((Sargs*) (sp + BY2WD));
if(up->procctl == Proc_tracesyscall){
syscallfmt(scallnr, ureg->pc, (va_list) up->s.args);
s = splhi();
up->procctl = Proc_stopme;
procctl();
splx(s);
startns = todget(nil);
}
if(scallnr >= nsyscall || systab[scallnr] == 0){
pprint("bad sys call number %lud pc %lux", scallnr, ureg->pc);
postnote(up, 1, "sys: bad sys call", NDebug);
error(Ebadarg);
}
up->psstate = sysctab[scallnr];
ret = systab[scallnr]((va_list)up->s.args);
poperror();
}else{
e = up->syserrstr;
up->syserrstr = up->errstr;
up->errstr = e;
}
if(up->nerrlab){
print("bad errstack [%lud]: %d extra\n", scallnr, up->nerrlab);
for(i = 0; i < NERR; i++)
print("sp=%lux pc=%lux\n", up->errlab[i].sp, up->errlab[i].pc);
panic("error stack");
}
ureg->r0 = ret;
if(up->procctl == Proc_tracesyscall){
stopns = todget(nil);
sysretfmt(scallnr, (va_list) up->s.args, ret, startns, stopns);
s = splhi();
up->procctl = Proc_stopme;
procctl();
splx(s);
}
up->insyscall = 0;
up->psstate = 0;
if(scallnr == NOTED)
noted(ureg, *((ulong *) up->s.args));
if(scallnr != RFORK && (up->procctl || up->nnote)){
splhi();
notify(ureg);
}
if(up->delaysched)
sched();
kexit(ureg);
splhi();
}
int
notify(Ureg *ureg)
{
int l;
ulong s, sp;
Note *n;
if(up->procctl)
procctl();
if(up->nnote == 0)
return 0;
if(up->fpstate == FPactive){
fpsave(up->fpsave);
up->fpstate = FPinactive;
}
up->fpstate |= FPillegal;
s = spllo();
qlock(&up->debug);
up->notepending = 0;
n = &up->note[0];
if(strncmp(n->msg, "sys:", 4) == 0){
l = strlen(n->msg);
if(l > ERRMAX-15) /* " pc=0x12345678\0" */
l = ERRMAX-15;
sprint(n->msg+l, " pc=0x%.8lux", ureg->pc);
}
if(n->flag!=NUser && (up->notified || up->notify==0)){
qunlock(&up->debug);
if(n->flag == NDebug)
pprint("suicide: %s\n", n->msg);
pexit(n->msg, n->flag!=NDebug);
}
if(up->notified){
qunlock(&up->debug);
splhi();
return 0;
}
if(!up->notify){
qunlock(&up->debug);
pexit(n->msg, n->flag!=NDebug);
}
sp = ureg->sp;
sp -= 256; /* debugging: preserve context causing problem */
sp -= sizeof(Ureg);
if(!okaddr((uintptr)up->notify, 1, 0)
|| !okaddr(sp-ERRMAX-4*BY2WD, sizeof(Ureg)+ERRMAX+4*BY2WD, 1)
|| ((uintptr) up->notify & 3) != 0
|| (sp & 3) != 0){
qunlock(&up->debug);
pprint("suicide: bad address in notify\n");
pexit("Suicide", 0);
}
memmove((Ureg*)sp, ureg, sizeof(Ureg));
*(Ureg**)(sp-BY2WD) = up->ureg; /* word under Ureg is old up->ureg */
up->ureg = (void*)sp;
sp -= BY2WD+ERRMAX;
memmove((char*)sp, up->note[0].msg, ERRMAX);
sp -= 3*BY2WD;
*(ulong*)(sp+2*BY2WD) = sp+3*BY2WD;
*(ulong*)(sp+1*BY2WD) = (ulong)up->ureg;
ureg->r0 = (uintptr) up->ureg;
ureg->sp = sp;
ureg->pc = (uintptr) up->notify;
ureg->r14 = 0;
up->notified = 1;
up->nnote--;
memmove(&up->lastnote, &up->note[0], sizeof(Note));
memmove(&up->note[0], &up->note[1], up->nnote*sizeof(Note));
qunlock(&up->debug);
splx(s);
return 1;
}
void
noted(Ureg *ureg, ulong arg0)
{
Ureg *nureg;
ulong oureg, sp;
qlock(&up->debug);
if(arg0 != NRSTR && !up->notified){
qunlock(&up->debug);
pprint("call to noted() when not notified\n");
pexit("Suicide", 0);
}
up->notified = 0;
nureg = up->ureg;
up->fpstate &= ~FPillegal;
oureg = (ulong) nureg;
if(!okaddr(oureg - BY2WD, BY2WD + sizeof(Ureg), 0) || (oureg & 3) != 0){
qunlock(&up->debug);
pprint("bad ureg in noted or call to noted when not notified\n");
pexit("Suicide", 0);
}
nureg->psr = nureg->psr & 0xf80f0000 | ureg->psr & 0x07f0ffff;
memmove(ureg, nureg, sizeof(Ureg));
switch(arg0){
case NCONT: case NRSTR:
if(!okaddr(nureg->pc, BY2WD, 0) || !okaddr(nureg->sp, BY2WD, 0) ||
(nureg->pc & 3) != 0 || (nureg->sp & 3) != 0){
qunlock(&up->debug);
pprint("suicide: trap in noted\n");
pexit("Suicide", 0);
}
up->ureg = (Ureg *) (*(ulong *) (oureg - BY2WD));
qunlock(&up->debug);
break;
case NSAVE:
if(!okaddr(nureg->pc, BY2WD, 0) || !okaddr(nureg->sp, BY2WD, 0) ||
(nureg->pc & 3) != 0 || (nureg->sp & 3) != 0){
qunlock(&up->debug);
pprint("suicide: trap in noted\n");
pexit("Suicide", 0);
}
qunlock(&up->debug);
sp = oureg - 4 * BY2WD - ERRMAX;
splhi();
ureg->sp = sp;
ureg->r0 = (uintptr) oureg;
((ulong *) sp)[1] = oureg;
((ulong *) sp)[0] = 0;
break;
default:
up->lastnote.flag = NDebug;
case NDFLT:
qunlock(&up->debug);
if(up->lastnote.flag == NDebug)
pprint("suicide: %s\n", up->lastnote.msg);
pexit(up->lastnote.msg, up->lastnote.flag != NDebug);
}
}
void
dumpstack(void)
{
callwithureg(_dumpstack);
}
void
dumpregs(Ureg *ureg)
{
iprint("trap: %lux psr %8.8lux type %2.2lux pc %8.8lux link %8.8lux\n",
ureg->type, ureg->psr, ureg->type, ureg->pc, ureg->link);
iprint("R14 %8.8lux R13 %8.8lux R12 %8.8lux R11 %8.8lux R10 %8.8lux\n",
ureg->r14, ureg->r13, ureg->r12, ureg->r11, ureg->r10);
iprint("R9 %8.8lux R8 %8.8lux R7 %8.8lux R6 %8.8lux R5 %8.8lux\n",
ureg->r9, ureg->r8, ureg->r7, ureg->r6, ureg->r5);
iprint("R4 %8.8lux R3 %8.8lux R2 %8.8lux R1 %8.8lux R0 %8.8lux\n",
ureg->r4, ureg->r3, ureg->r2, ureg->r1, ureg->r0);
iprint("pc %#lux link %#lux\n", ureg->pc, ureg->link);
}
void
setkernur(Ureg *ureg, Proc *p)
{
ureg->pc = p->sched.pc;
ureg->sp = p->sched.sp + 4;
ureg->r14 = (uintptr) sched;
}
void
setregisters(Ureg* ureg, char* pureg, char* uva, int n)
{
ulong v;
v = ureg->psr;
memmove(pureg, uva, n);
ureg->psr = ureg->psr & 0xf80f0000 | v & 0x07f0ffff;
}
void
callwithureg(void (*f) (Ureg *))
{
Ureg u;
u.pc = getcallerpc(&f);
u.sp = (uintptr) &f - 4;
f(&u);
}
uintptr
userpc(void)
{
Ureg *ur;
ur = up->dbgreg;
return ur->pc;
}
uintptr
dbgpc(Proc *)
{
Ureg *ur;
ur = up->dbgreg;
if(ur == nil)
return 0;
return ur->pc;
}
void
procsave(Proc *p)
{
uvlong t;
if(p->fpstate == FPactive){
if(p->state == Moribund)
fpclear();
else
fpsave(p->fpsave);
p->fpstate = FPinactive;
}
cycles(&t);
p->kentry -= t;
p->pcycles += t;
l1switch(&m->l1, 0);
}
void
procrestore(Proc *p)
{
uvlong t;
if(p->kp)
return;
cycles(&t);
p->kentry += t;
p->pcycles -= t;
}
static void
linkproc(void)
{
spllo();
up->kpfun(up->kparg);
pexit("kproc dying", 0);
}
void
kprocchild(Proc* p, void (*func)(void*), void* arg)
{
p->sched.pc = (uintptr) linkproc;
p->sched.sp = (uintptr) p->kstack + KSTACK;
p->kpfun = func;
p->kparg = arg;
}
void
forkchild(Proc *p, Ureg *ureg)
{
Ureg *cureg;
p->sched.pc = (uintptr) forkret;
p->sched.sp = (uintptr) p->kstack + KSTACK - sizeof(Ureg);
cureg = (Ureg*) p->sched.sp;
memmove(cureg, ureg, sizeof(Ureg));
cureg->r0 = 0;
p->psstate = 0;
p->insyscall = 0;
}
uintptr
execregs(uintptr entry, ulong ssize, ulong nargs)
{
ulong *sp;
Ureg *ureg;
sp = (ulong*)(USTKTOP - ssize);
*--sp = nargs;
ureg = up->dbgreg;
ureg->sp = (uintptr) sp;
ureg->pc = entry;
ureg->r14 = 0;
return USTKTOP-sizeof(Tos);
}