xref: /openbsd/sys/arch/hppa/hppa/trap.c (revision 906a25e0)

/*	$OpenBSD: trap.c,v 1.58 2003/01/09 20:48:56 mickey Exp $	*/

/*
 * Copyright (c) 1998-2003 Michael Shalayeff
 * 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 Michael Shalayeff.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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 MIND,
 * 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.
 */

/* #define TRAPDEBUG */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/syscall.h>
#include <sys/ktrace.h>
#include <sys/proc.h>
#include <sys/signalvar.h>
#include <sys/user.h>

#include <net/netisr.h>

#include "systrace.h"
#include <dev/systrace.h>

#include <uvm/uvm.h>

#include <machine/autoconf.h>

#ifdef DDB
#include <machine/db_machdep.h>
#ifdef TRAPDEBUG
#include <ddb/db_output.h>
#endif
#endif

const char *trap_type[] = {
	"invalid",
	"HPMC",
	"power failure",
	"recovery counter",
	"external interrupt",
	"LPMC",
	"ITLB miss fault",
	"instruction protection",
	"Illegal instruction",
	"break instruction",
	"privileged operation",
	"privileged register",
	"overflow",
	"conditional",
	"assist exception",
	"DTLB miss",
	"ITLB non-access miss",
	"DTLB non-access miss",
	"data protection/rights/alignment",
	"data break",
	"TLB dirty",
	"page reference",
	"assist emulation",
	"higher-priv transfer",
	"lower-priv transfer",
	"taken branch",
	"data access rights",
	"data protection",
	"unaligned data ref",
};
int trap_types = sizeof(trap_type)/sizeof(trap_type[0]);

int want_resched, astpending;

void
userret(struct proc *p, register_t pc, u_quad_t oticks)
{
	int sig;

	/* take pending signals */
	while ((sig = CURSIG(p)) != 0)
		postsig(sig);

	p->p_priority = p->p_usrpri;
	if (astpending) {
		astpending = 0;
		if (p->p_flag & P_OWEUPC) {
			p->p_flag &= ~P_OWEUPC;
			ADDUPROF(p);
		}
	}
	if (want_resched) {
		/*
		 * We're being preempted.
		 */
		preempt(NULL);
		while ((sig = CURSIG(p)) != 0)
			postsig(sig);
	}

	/*
	 * If profiling, charge recent system time to the trapped pc.
	 */
	if (p->p_flag & P_PROFIL) {
		extern int psratio;

		addupc_task(p, pc, (int)(p->p_sticks - oticks) * psratio);
	}

	curpriority = p->p_priority;
}

void
trap(type, frame)
	int type;
	struct trapframe *frame;
{
	struct proc *p = curproc;
	vaddr_t va;
	struct vm_map *map;
	struct vmspace *vm;
	register vm_prot_t vftype;
	register pa_space_t space;
	union sigval sv;
	u_int opcode;
	int ret, trapnum;
	const char *tts;
	vm_fault_t fault = VM_FAULT_INVALID;
#ifdef DIAGNOSTIC
	int oldcpl = cpl;
#endif

	trapnum = type & ~T_USER;
	opcode = frame->tf_iir;
	if (trapnum == T_ITLBMISS ||
	    trapnum == T_EXCEPTION || trapnum == T_EMULATION) {
		va = frame->tf_iioq_head;
		space = frame->tf_iisq_head;
		vftype = VM_PROT_EXECUTE;
	} else {
		va = frame->tf_ior;
		space = frame->tf_isr;
		/* what is the vftype for the T_ITLBMISSNA ??? XXX */
		if (va == frame->tf_iioq_head)
			vftype = VM_PROT_EXECUTE;
		else if (inst_store(opcode))
			vftype = VM_PROT_WRITE;
		else
			vftype = VM_PROT_READ;
	}

	if (frame->tf_flags & TFF_LAST)
		p->p_md.md_regs = frame;

#ifdef TRAPDEBUG
	if (trapnum > trap_types)
		tts = "reserved";
	else
		tts = trap_type[trapnum];

	if (trapnum != T_INTERRUPT && trapnum != T_IBREAK)
		db_printf("trap: %x, %s for %x:%x at %x:%x, fl=%x, fp=%p\n",
		    type, tts, space, va, frame->tf_iisq_head,
		    frame->tf_iioq_head, frame->tf_flags, frame);
	else if (trapnum  == T_IBREAK)
		db_printf("trap: break instruction %x:%x at %x:%x, fp=%p\n",
		    break5(opcode), break13(opcode),
		    frame->tf_iisq_head, frame->tf_iioq_head, frame);

	{
		extern int etext;
		if (frame < (struct trapframe *)&etext) {
			printf("trap: bogus frame ptr %p\n", frame);
			goto dead_end;
		}
	}
#endif
	if (trapnum != T_INTERRUPT)
		mtctl(frame->tf_eiem, CR_EIEM);

	switch (type) {
	case T_NONEXIST:
	case T_NONEXIST|T_USER:
		/* we've got screwed up by the central scrutinizer */
		printf("trap: elvis has just left the building!\n");
		goto dead_end;

	case T_RECOVERY:
	case T_RECOVERY|T_USER:
		/* XXX will implement later */
		printf("trap: handicapped");
		goto dead_end;

#ifdef DIAGNOSTIC
	case T_EXCEPTION:
		panic("FPU/SFU emulation botch");

		/* these just can't happen ever */
	case T_PRIV_OP:
	case T_PRIV_REG:
		/* these just can't make it to the trap() ever */
	case T_HPMC:      case T_HPMC | T_USER:
#endif
	case T_IBREAK:
	case T_DATALIGN:
	case T_DBREAK:
	dead_end:
#ifdef DDB
		if (kdb_trap (type, va, frame)) {
			if (type == T_IBREAK) {
				/* skip break instruction */
				frame->tf_iioq_head = frame->tf_iioq_tail;
				frame->tf_iioq_tail += 4;
			}
			return;
		}
#else
		if (type == T_DATALIGN)
			panic ("trap: %s at 0x%x", tts, va);
		else
			panic ("trap: no debugger for \"%s\" (%d)", tts, type);
#endif
		break;

	case T_IBREAK | T_USER:
		/* XXX */
		frame->tf_iioq_head = frame->tf_iioq_tail;
		frame->tf_iioq_tail += 4;
	case T_DBREAK | T_USER:
		/* pass to user debugger */
		break;

	case T_EXCEPTION | T_USER: {
		u_int64_t *fpp = (u_int64_t *)frame->tf_cr30;
		u_int32_t *pex;
		int i, flt;

		pex = (u_int32_t *)&fpp[0];
		for (i = 0, pex++; i < 7 && !*pex; i++, pex++);
		flt = 0;
		if (i < 7) {
			u_int32_t stat = HPPA_FPU_OP(*pex);
			if (stat == HPPA_FPU_UNMPL)
				flt = FPE_FLTINV;
			else if (stat & HPPA_FPU_V)
				flt = FPE_FLTINV;
			else if (stat & HPPA_FPU_Z)
				flt = FPE_FLTDIV;
			else if (stat & HPPA_FPU_I)
				flt = FPE_FLTRES;
			else if (stat & HPPA_FPU_O)
				flt = FPE_FLTOVF;
			else if (stat & HPPA_FPU_U)
				flt = FPE_FLTUND;
			/* still left: under/over-flow w/ inexact */
			*pex = 0;
		}
		/* reset the trap flag, as if there was none */
		fpp[0] &= ~(((u_int64_t)HPPA_FPU_T) << 32);
		/* flush out, since load is done from phys, only 4 regs */
		fdcache(HPPA_SID_KERNEL, (vaddr_t)fpp, 8 * 4);

		sv.sival_int = va;
		trapsignal(p, SIGFPE, type &~ T_USER, flt, sv);
		}
		break;

	case T_EMULATION:
		panic("trap: emulation trap in the kernel");
		break;

	case T_EMULATION | T_USER:
		sv.sival_int = va;
		trapsignal(p, SIGILL, type &~ T_USER, ILL_ILLOPC, sv);
		break;

	case T_OVERFLOW | T_USER:
		sv.sival_int = va;
		trapsignal(p, SIGFPE, type &~ T_USER, FPE_INTOVF, sv);
		break;

	case T_CONDITION | T_USER:
		break;

	case T_ILLEGAL | T_USER:
		sv.sival_int = va;
		trapsignal(p, SIGILL, type &~ T_USER, ILL_ILLOPC, sv);
		break;

	case T_PRIV_OP | T_USER:
		sv.sival_int = va;
		trapsignal(p, SIGILL, type &~ T_USER, ILL_PRVOPC, sv);
		break;

	case T_PRIV_REG | T_USER:
		sv.sival_int = va;
		trapsignal(p, SIGILL, type &~ T_USER, ILL_PRVREG, sv);
		break;

		/* these should never got here */
	case T_HIGHERPL | T_USER:
	case T_LOWERPL | T_USER:
		sv.sival_int = va;
		trapsignal(p, SIGSEGV, vftype, SEGV_ACCERR, sv);
		break;

	case T_IPROT | T_USER:
	case T_DPROT | T_USER:
		sv.sival_int = va;
		trapsignal(p, SIGSEGV, vftype, SEGV_ACCERR, sv);
		break;

	case T_DATACC:   	case T_USER | T_DATACC:
		fault = VM_FAULT_PROTECT;
	case T_ITLBMISS:	case T_USER | T_ITLBMISS:
	case T_DTLBMISS:	case T_USER | T_DTLBMISS:
	case T_ITLBMISSNA:	case T_USER | T_ITLBMISSNA:
	case T_DTLBMISSNA:	case T_USER | T_DTLBMISSNA:
	case T_TLB_DIRTY:	case T_USER | T_TLB_DIRTY:
		/*
		 * user faults out of user addr space are always a fail,
		 * this happens on va >= VM_MAXUSER_ADDRESS, where
		 * space id will be zero and therefore cause
		 * a misbehave lower in the code.
		 */
		if (type & T_USER && va >= VM_MAXUSER_ADDRESS) {
			sv.sival_int = va;
			trapsignal(p, SIGSEGV, vftype, SEGV_ACCERR, sv);
			break;
		}

		if (!(vm = p->p_vmspace)) {
			printf("trap: no vm, p=%p\n", p);
			goto dead_end;
		}

		/*
		 * it could be a kernel map for exec_map faults
		 */
		if (!(type & T_USER) && space == HPPA_SID_KERNEL)
			map = kernel_map;
		else
			map = &vm->vm_map;

		if (map->pmap->pm_space != space) {
			if (map->pmap->pm_space != HPPA_SID_KERNEL) {
				sv.sival_int = va;
				trapsignal(p, SIGSEGV, vftype, SEGV_MAPERR, sv);
			} else {
				printf("trap: space missmatch %d != %d\n",
				    space, map->pmap->pm_space);
				goto dead_end;
			}
		}

#ifdef TRAPDEBUG
		if (space == -1) {
			extern int pmapdebug;
			pmapdebug = 0xffffff;
		}
#endif
		ret = uvm_fault(map, hppa_trunc_page(va), fault, vftype);

#ifdef TRAPDEBUG
		if (space == -1) {
			extern int pmapdebug;
			pmapdebug = 0;
		}

		printf("uvm_fault(%p, %x, %d, %d)=%d\n",
		    map, va, 0, vftype, ret);
#endif

		/*
		 * If this was a stack access we keep track of the maximum
		 * accessed stack size.  Also, if uvm_fault gets a protection
		 * failure it is due to accessing the stack region outside
		 * the current limit and we need to reflect that as an access
		 * error.
		 */
		if (space != 0 && va < (vaddr_t)vm->vm_minsaddr &&
		    va >= (vaddr_t)vm->vm_maxsaddr + ctob(vm->vm_ssize)) {
			if (ret == 0) {
				vsize_t nss = btoc(va - USRSTACK + NBPG - 1);
				if (nss > vm->vm_ssize)
					vm->vm_ssize = nss;
			} else if (ret == EACCES)
				ret = EFAULT;
		}

		if (ret != 0) {
			if (type & T_USER) {
				sv.sival_int = va;
				trapsignal(p, SIGSEGV, vftype,
				    ret == EACCES? SEGV_ACCERR : SEGV_MAPERR,
				    sv);
			} else {
				if (p && p->p_addr->u_pcb.pcb_onfault) {
					frame->tf_iioq_tail = 4 +
					    (frame->tf_iioq_head =
						p->p_addr->u_pcb.pcb_onfault);
#ifdef DDB
					frame->tf_iir = 0;
#endif
				} else {
					panic("trap: "
					    "uvm_fault(%p, %x, %d, %d): %d",
					    map, va, 0, vftype, ret);
				}
			}
		}
		break;

	case T_DATALIGN | T_USER:
		sv.sival_int = va;
		trapsignal(p, SIGBUS, vftype, BUS_ADRALN, sv);
		break;

	case T_INTERRUPT:
	case T_INTERRUPT|T_USER:
		cpu_intr(frame);
		break;

	case T_CONDITION:
		panic("trap: divide by zero in the kernel");
		break;

	case T_LOWERPL:
	case T_DPROT:
	case T_IPROT:
	case T_OVERFLOW:
	case T_ILLEGAL:
	case T_HIGHERPL:
	case T_TAKENBR:
	case T_POWERFAIL:
	case T_LPMC:
	case T_PAGEREF:
	case T_DATAPID:  	case T_DATAPID  | T_USER:
		if (0 /* T-chip */) {
			break;
		}
		/* FALLTHROUGH to unimplemented */
	default:
#if 0
if (kdb_trap (type, va, frame))
	return;
#endif
		panic("trap: unimplemented \'%s\' (%d)", tts, trapnum);
	}

#ifdef DIAGNOSTIC
	if (cpl != oldcpl)
		printf("WARNING: SPL (%d) NOT LOWERED ON "
		    "TRAP (%d) EXIT\n", cpl, trapnum);
#endif

	if (trapnum != T_INTERRUPT)
		splx(cpl);	/* process softints */

	if (type & T_USER)
		userret(p, frame->tf_iioq_head, 0);
}

void
child_return(arg)
	void *arg;
{
	struct proc *p = (struct proc *)arg;
	userret(p, p->p_md.md_regs->tf_iioq_head, 0);
#ifdef KTRACE
	if (KTRPOINT(p, KTR_SYSRET))
		ktrsysret(p, SYS_fork, 0, 0);
#endif
}


/*
 * call actual syscall routine
 */
void
syscall(struct trapframe *frame)
{
	register struct proc *p = curproc;
	register const struct sysent *callp;
	int retq, nsys, code, argsize, argoff, oerror, error;
	register_t args[8], rval[2];
#ifdef DIAGNOSTIC
	int oldcpl = cpl;
#endif

	uvmexp.syscalls++;

	if (!USERMODE(frame->tf_iioq_head))
		panic("syscall");

	p->p_md.md_regs = frame;
	nsys = p->p_emul->e_nsysent;
	callp = p->p_emul->e_sysent;

	argoff = 4; retq = 0;
	switch (code = frame->tf_t1) {
	case SYS_syscall:
		code = frame->tf_arg0;
		args[0] = frame->tf_arg1;
		args[1] = frame->tf_arg2;
		args[2] = frame->tf_arg3;
		argoff = 3;
		break;
	case SYS___syscall:
		if (callp != sysent)
			break;
		/*
		 * this works, because quads get magically swapped
		 * due to the args being layed backwards on the stack
		 * and then copied in words
		 */
		code = frame->tf_arg0;
		args[0] = frame->tf_arg2;
		args[1] = frame->tf_arg3;
		argoff = 2;
		retq = 1;
		break;
	default:
		args[0] = frame->tf_arg0;
		args[1] = frame->tf_arg1;
		args[2] = frame->tf_arg2;
		args[3] = frame->tf_arg3;
		break;
	}

	if (code < 0 || code >= nsys)
		callp += p->p_emul->e_nosys;	/* bad syscall # */
	else
		callp += code;

	oerror = error = 0;
	if ((argsize = callp->sy_argsize)) {
		int i;

		for (i = 0, argsize -= argoff * 4;
		    argsize > 0; i++, argsize -= 4) {
			error = copyin((void *)(frame->tf_sp +
			    HPPA_FRAME_ARG(i + 4)), args + i + argoff, 4);

			if (error)
				break;
		}

		/*
		 * coming from syscall() or __syscall we must be
		 * having one of those w/ a 64 bit arguments,
		 * which needs a word swap due to the order
		 * of the arguments on the stack.
		 * this assumes that none of 'em are called
		 * by their normal syscall number, maybe a regress
		 * test should be used, to whatch the behaviour.
		 */
		if (!error && argoff < 4) {
			int t;

			i = 0;
			switch (code) {
			case SYS_lseek:		retq = 0;
			case SYS_truncate:
			case SYS_ftruncate:	i = 2;	break;
			case SYS_preadv:
			case SYS_pwritev:
			case SYS_pread:
			case SYS_pwrite:	i = 4;	break;
			case SYS_mmap:		i = 6;	break;
			}

			if (i) {
				t = args[i];
				args[i] = args[i + 1];
				args[i + 1] = t;
			}
		}
	}

#ifdef SYSCALL_DEBUG
	scdebug_call(p, code, args);
#endif
#ifdef KTRACE
	if (KTRPOINT(p, KTR_SYSCALL))
		ktrsyscall(p, code, callp->sy_argsize, args);
#endif
	if (error)
		goto bad;

	rval[0] = 0;
	rval[1] = frame->tf_ret1;
#if NSYSTRACE > 0
	if (ISSET(p->p_flag, P_SYSTRACE))
		oerror = error = systrace_redirect(code, p, args, rval);
	else
#endif
		oerror = error = (*callp->sy_call)(p, args, rval);
	switch (error) {
	case 0:
		p = curproc;			/* changes on exec() */
		frame = p->p_md.md_regs;
		frame->tf_ret0 = rval[0];
		frame->tf_ret1 = rval[!retq];
		frame->tf_t1 = 0;
		break;
	case ERESTART:
		frame->tf_iioq_head -= 12;
		frame->tf_iioq_tail -= 12;
		break;
	case EJUSTRETURN:
		p = curproc;
		frame = p->p_md.md_regs;
		break;
	default:
	bad:
		if (p->p_emul->e_errno)
			error = p->p_emul->e_errno[error];
		frame->tf_t1 = error;
		break;
	}
#ifdef SYSCALL_DEBUG
	scdebug_ret(p, code, oerror, rval);
#endif
	userret(p, frame->tf_iioq_head, 0);
	splx(cpl);	/* process softints */
#ifdef KTRACE
	if (KTRPOINT(p, KTR_SYSRET))
		ktrsysret(p, code, oerror, rval[0]);
#endif
#ifdef DIAGNOSTIC
	if (cpl != oldcpl)
		printf("WARNING: SPL (0x%x) NOT LOWERED ON "
		    "syscall(0x%x, 0x%x, 0x%x, 0x%x...) EXIT, PID %d\n",
		    cpl, code, args[0], args[1], args[2], p->p_pid);
#endif
}