~kris/9p

9hist

ref: a68bb721e9fcc08363e1ebcf97bd2a8b7c7352b4 9hist/gnot/trap.c -rw-r--r-- 5.3 KiB
a68bb721 — David du Colombier Plan 9 from Bell Labs 1990-04-19 36 years ago
                                                                                
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#include	"u.h"
#include	"lib.h"
#include	"mem.h"
#include	"dat.h"
#include	"fns.h"
#include	"ureg.h"
#include	"io.h"

void	notify(Ureg*);
void	noted(Ureg**);
void	rfnote(Ureg**);

char *regname[]={
	"R0",
	"R1",
	"R2",
	"R3",
	"R4",
	"R5",
	"R6",
	"R7",
	"A0",
	"A1",
	"A2",
	"A3",
	"A4",
	"A5",
	"A6",
	"A7",
};

long	ticks;

char *trapname[]={
	"reset isp",
	"reset ipc",
	"bus error",
	"address error",
	"illegal instruction",
	"zero divide",
	"chk, chk2 instruction",
	"cptrapcc, trapcc, trapv instruction",
	"privilege violation",
	"trace",
	"line 1010 emulator",
	"line 1111 emulator",
	"reserved",
	"coprocessor protocol violation",
	"format error",
	"uninitialized interrupt",
	"unassigned 0x40",
	"unassigned 0x44",
	"unassigned 0x48",
	"unassigned 0x4C",
	"unassigned 0x50",
	"unassigned 0x54",
	"unassigned 0x58",
	"unassigned 0x5C",
	"spurious interrupt",
	"level 1 autovector (tac)",
	"level 2 autovector (port)",
	"level 3 autovector (incon)",
	"level 4 autovector (mouse)",
	"level 5 autovector (uart)",
	"level 6 autovector (sync)",
	"level 7 autovector",
};

char*
excname(unsigned vo)
{
	static char buf[32];	/* BUG: not reentrant! */

	vo &= 0x0FFF;
	vo >>= 2;
	if(vo < sizeof trapname/sizeof(char*))
		return trapname[vo];
	sprint(buf, "offset 0x%ux", vo<<2);
	return buf;
}

void
trap(Ureg *ur)
{
	int user;
	char buf[64];

	user = !(ur->sr&SUPER);

	if(u)
		u->p->pc = ur->pc;		/* BUG */
	if(user){
		sprint(buf, "pc=%lux trap: %s", ur->pc, excname(ur->vo));
		postnote(u->p, 1, buf, NDebug);
	}else{
		print("kernel trap vo=%ux pc=%lux\n", ur->vo, ur->pc);
		dumpregs(ur);
		exit();
	}
	if(user && u->nnote)
		notify(ur);
}

void
dumpstack(void)
{
	ulong l, v;
	extern ulong etext;

	if(u)
		for(l=(ulong)&l; l<USERADDR+BY2PG; l+=4){
			v = *(ulong*)l;
			if(KTZERO < v && v < (ulong)&etext)
				print("%lux=%lux\n", l, v);
		}
}

void
dumpregs(Ureg *ur)
{
	int i;
	ulong *l;

	if(u)
		print("registers for %s %d\n", u->p->text, u->p->pid);
	else
		print("registers for kernel\n");
	print("SR=%ux PC=%lux VO=%lux, USP=%lux\n", ur->sr, ur->pc, ur->vo, ur->usp);
	l = &ur->r0;
	for(i=0; i<sizeof regname/sizeof(char*); i+=2, l+=2)
		print("%s\t%.8lux\t%s\t%.8lux\n", regname[i], l[0], regname[i+1], l[1]);
	dumpstack();
}

/*
 * Call user, if necessary, with note
 */
void
notify(Ureg *ur)
{
	ulong sp;

	lock(&u->p->debug);
	if(u->nnote==0){
		unlock(&u->p->debug);
		return;
	}
	if(u->note[0].flag!=NUser && (u->notified || u->notify==0)){
		if(u->note[0].flag == NDebug)
			pprint("suicide: %s\n", u->note[0].msg);
    Die:
		unlock(&u->p->debug);
		pexit(u->note[0].msg, u->note[0].flag!=NDebug);
	}
	if(!u->notified){
		if(!u->notify)
			goto Die;
		#ifdef asdfasdf
		sp = ur->sp;
		sp -= sizeof(Ureg);
		u->ureg = (void*)sp;
		memcpy((Ureg*)sp, ur, sizeof(Ureg));
		sp -= ERRLEN;
		memcpy((char*)sp, u->note[0].msg, ERRLEN);
		sp -= 3*BY2WD;
		*(ulong*)(sp+2*BY2WD) = sp+3*BY2WD;	/* arg 2 is string */
		*(ulong*)(sp+1*BY2WD) = (ulong)u->ureg;	/* arg 1 is ureg* */
		*(ulong*)(sp+0*BY2WD) = 0;		/* arg 0 is pc */
		ur->sp = sp;
		ur->pc = (ulong)u->notify;
		u->notified = 1;
		u->nnote--;
		memcpy(&u->note[0], &u->note[1], u->nnote*sizeof(Note));
		#endif
		panic("notify");
	}
	unlock(&u->p->debug);
}

/*
 * Return user to state before notify()
 */
void
noted(Ureg **urp)
{
	#ifdef asdfasdf
	lock(&u->p->debug);
	u->notified = 0;
	memcpy(*urp, u->ureg, sizeof(Ureg));
	unlock(&u->p->debug);
	splhi();
	rfnote(urp);
	#endif
	panic("noted");
}

#undef	CHDIR	/* BUG */
#include "/sys/src/libc/680209sys/sys.h"

typedef long Syscall(ulong*);
Syscall	sysr1, sysfork, sysexec, sysgetpid, syssleep, sysexits, syslasterr, syswait;
Syscall	sysopen, sysclose, sysread, syswrite, sysseek, syserrstr, sysaccess, sysstat, sysfstat;
Syscall sysdup, syschdir, sysforkpgrp, sysbind, sysmount, syspipe, syscreate, sysuserstr;
Syscall	sysbrk_, sysremove, syswstat, sysfwstat;

Syscall *systab[]={
	sysr1,
	sysaccess,
	sysbind,
	syschdir,
	sysclose,
	sysdup,
	syserrstr,
	sysexec,
	sysexits,
	sysfork,
	sysforkpgrp,
	sysfstat,
	syslasterr,
	sysmount,
	sysopen,
	sysread,
	sysseek,
	syssleep,
	sysstat,
	syswait,
	syswrite,
	syspipe,
	syscreate,
	sysuserstr,
	sysbrk_,
	sysremove,
	syswstat,
	sysfwstat,
};

long
syscall(Ureg *aur)
{
	long ret;
	ulong sp;
	ulong r0;
	Ureg *ur;

	u->p->insyscall = 1;
	ur = aur;
	u->p->pc = ur->pc;
	if(ur->sr & SUPER)
		panic("recursive system call");
#ifdef asdf
	/*
	 * since the system call interface does not
	 * guarantee anything about registers
	 */
	if(u->p->fpstate == FPactive) {
		u->p->fpstate = FPinit;		/* BUG */
		ur->status &= ~CU1;
	}
#endif
	r0 = ur->r0;
	sp = ur->usp;
	if(r0 >= sizeof systab/BY2WD)
		panic("syscall %d\n", r0);
	if(sp & (BY2WD-1))
		panic("syscall odd sp");
	if(sp<(USTKTOP-BY2PG) || sp>(USTKTOP-4*BY2WD))
		validaddr(sp, 4*BY2WD, 0);

	u->nerrlab = 0;
	ret = -1;
	if(!waserror())
		ret = (*systab[r0])((ulong*)(sp+BY2WD));
/* else print("syscall %d err %d %d\n", r0, u->error.type, u->error.code); /**/
	u->nerrlab = 0;
	u->p->insyscall = 0;
	if(r0 == NOTED)	/* ugly hack */
		noted(&aur);	/* doesn't return */
	if(u->nnote){
		ur->r0 = ret;
		notify(ur);
	}
	return ret;
}

void
error(Chan *c, int code)
{
	if(c){
		u->error.type = c->type;
		u->error.dev = c->dev;
	}else{
		u->error.type = 0;
		u->error.dev = 0;
	}
	u->error.code = code;
	nexterror();
}

void
nexterror(void)
{
	gotolabel(&u->errlab[--u->nerrlab]);
}