xref: /netbsd-src/sys/arch/powerpc/ibm4xx/trap.c (revision cac8e449158efc7261bebc8657cbb0125a2cfdde)
1 /*	$NetBSD: trap.c,v 1.48 2008/01/02 11:48:27 ad Exp $	*/
2 
3 /*
4  * Copyright 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*
39  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
40  * Copyright (C) 1995, 1996 TooLs GmbH.
41  * All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by TooLs GmbH.
54  * 4. The name of TooLs GmbH may not be used to endorse or promote products
55  *    derived from this software without specific prior written permission.
56  *
57  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
58  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
59  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
60  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
61  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
62  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
63  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
64  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
65  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
66  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
67  */
68 
69 #include <sys/cdefs.h>
70 __KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.48 2008/01/02 11:48:27 ad Exp $");
71 
72 #include "opt_altivec.h"
73 #include "opt_ddb.h"
74 #include "opt_kgdb.h"
75 
76 #include <sys/param.h>
77 #include <sys/proc.h>
78 #include <sys/reboot.h>
79 #include <sys/syscall.h>
80 #include <sys/systm.h>
81 #include <sys/user.h>
82 #include <sys/pool.h>
83 #include <sys/userret.h>
84 #include <sys/kauth.h>
85 
86 #if defined(KGDB)
87 #include <sys/kgdb.h>
88 #endif
89 
90 #include <uvm/uvm_extern.h>
91 
92 #include <dev/cons.h>
93 
94 #include <machine/cpu.h>
95 #include <machine/db_machdep.h>
96 #include <machine/fpu.h>
97 #include <machine/frame.h>
98 #include <machine/pcb.h>
99 #include <machine/psl.h>
100 #include <machine/trap.h>
101 
102 #include <powerpc/spr.h>
103 #include <powerpc/ibm4xx/pmap.h>
104 #include <powerpc/ibm4xx/tlb.h>
105 #include <powerpc/fpu/fpu_extern.h>
106 
107 /* These definitions should probably be somewhere else			XXX */
108 #define	FIRSTARG	3		/* first argument is in reg 3 */
109 #define	NARGREG		8		/* 8 args are in registers */
110 #define	MOREARGS(sp)	((void *)((int)(sp) + 8)) /* more args go here */
111 
112 static int fix_unaligned __P((struct lwp *l, struct trapframe *frame));
113 
114 void trap __P((struct trapframe *));	/* Called from locore / trap_subr */
115 /* Why are these not defined in a header? */
116 int badaddr __P((void *, size_t));
117 int badaddr_read __P((void *, size_t, int *));
118 int ctx_setup __P((int, int));
119 
120 #ifdef DEBUG
121 #define TDB_ALL	0x1
122 int trapdebug = /* TDB_ALL */ 0;
123 #define	DBPRINTF(x, y)	if (trapdebug & (x)) printf y
124 #else
125 #define DBPRINTF(x, y)
126 #endif
127 
128 void
129 trap(struct trapframe *frame)
130 {
131 	struct lwp *l = curlwp;
132 	struct proc *p = l ? l->l_proc : NULL;
133 	int type = frame->exc;
134 	int ftype, rv;
135 	ksiginfo_t ksi;
136 
137 	KASSERT(l == 0 || (l->l_stat == LSONPROC));
138 
139 	if (frame->srr1 & PSL_PR) {
140 		LWP_CACHE_CREDS(l, p);
141 		type |= EXC_USER;
142 	}
143 
144 	ftype = VM_PROT_READ;
145 
146 	DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n",
147 	    type, frame->srr0, frame, &frame));
148 
149 	switch (type) {
150 	case EXC_DEBUG|EXC_USER:
151 		{
152 			int srr2, srr3;
153 
154 			__asm volatile("mfspr %0,0x3f0" :
155 			    "=r" (rv), "=r" (srr2), "=r" (srr3) :);
156 			printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2,
157 			    srr3);
158 			/* XXX fall through or break here?! */
159 		}
160 		/*
161 		 * DEBUG intr -- probably single-step.
162 		 */
163 	case EXC_TRC|EXC_USER:
164 		frame->srr1 &= ~PSL_SE;
165 		KSI_INIT_TRAP(&ksi);
166 		ksi.ksi_signo = SIGTRAP;
167 		ksi.ksi_trap = EXC_TRC;
168 		ksi.ksi_addr = (void *)frame->srr0;
169 		trapsignal(l, &ksi);
170 		break;
171 
172 	/*
173 	 * If we could not find and install appropriate TLB entry, fall through.
174 	 */
175 
176 	case EXC_DSI:
177 		/* FALLTHROUGH */
178 	case EXC_DTMISS:
179 		{
180 			struct vm_map *map;
181 			vaddr_t va;
182 			struct faultbuf *fb = NULL;
183 
184 			va = frame->dar;
185 			if (frame->tf_xtra[TF_PID] == KERNEL_PID) {
186 				map = kernel_map;
187 			} else {
188 				map = &p->p_vmspace->vm_map;
189 			}
190 
191 			if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ))
192 				ftype = VM_PROT_WRITE;
193 
194 			DBPRINTF(TDB_ALL,
195 			    ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n",
196 			    frame->srr0,
197 			    (ftype & VM_PROT_WRITE) ? "write" : "read",
198 			    (void *)va, frame->tf_xtra[TF_ESR]));
199 			rv = uvm_fault(map, trunc_page(va), ftype);
200 			if (rv == 0)
201 				goto done;
202 			if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) {
203 				frame->tf_xtra[TF_PID] = KERNEL_PID;
204 				frame->srr0 = fb->fb_pc;
205 				frame->srr1 |= PSL_IR; /* Re-enable IMMU */
206 				frame->fixreg[1] = fb->fb_sp;
207 				frame->fixreg[2] = fb->fb_r2;
208 				frame->fixreg[3] = 1; /* Return TRUE */
209 				frame->cr = fb->fb_cr;
210 				memcpy(&frame->fixreg[13], fb->fb_fixreg,
211 				    sizeof(fb->fb_fixreg));
212 				goto done;
213 			}
214 		}
215 		goto brain_damage;
216 
217 	case EXC_DSI|EXC_USER:
218 		/* FALLTHROUGH */
219 	case EXC_DTMISS|EXC_USER:
220 		if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ))
221 			ftype = VM_PROT_WRITE;
222 
223 		DBPRINTF(TDB_ALL,
224 		    ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n",
225 		    frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read",
226 		    frame->dar, frame->tf_xtra[TF_ESR]));
227 		KASSERT(l == curlwp && (l->l_stat == LSONPROC));
228 		rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar),
229 		    ftype);
230 		if (rv == 0) {
231 			break;
232 		}
233 		KSI_INIT_TRAP(&ksi);
234 		ksi.ksi_signo = SIGSEGV;
235 		ksi.ksi_trap = EXC_DSI;
236 		ksi.ksi_addr = (void *)frame->dar;
237 		if (rv == ENOMEM) {
238 			printf("UVM: pid %d (%s) lid %d, uid %d killed: "
239 			    "out of swap\n",
240 			    p->p_pid, p->p_comm, l->l_lid,
241 			    l->l_cred ?
242 			    kauth_cred_geteuid(l->l_cred) : -1);
243 			ksi.ksi_signo = SIGKILL;
244 		}
245 		trapsignal(l, &ksi);
246 		break;
247 
248 	case EXC_ITMISS|EXC_USER:
249 	case EXC_ISI|EXC_USER:
250 		ftype = VM_PROT_EXECUTE;
251 		DBPRINTF(TDB_ALL,
252 		    ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n",
253 		    frame->srr0, frame));
254 		rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0),
255 		    ftype);
256 		if (rv == 0) {
257 			break;
258 		}
259 		KSI_INIT_TRAP(&ksi);
260 		ksi.ksi_signo = SIGSEGV;
261 		ksi.ksi_trap = EXC_ISI;
262 		ksi.ksi_addr = (void *)frame->srr0;
263 		ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR);
264 		trapsignal(l, &ksi);
265 		break;
266 
267 	case EXC_AST|EXC_USER:
268 		curcpu()->ci_astpending = 0;	/* we are about to do it */
269 		uvmexp.softs++;
270 		if (l->l_pflag & LP_OWEUPC) {
271 			l->l_pflag &= ~LP_OWEUPC;
272 			ADDUPROF(l);
273 		}
274 		/* Check whether we are being preempted. */
275 		if (curcpu()->ci_want_resched)
276 			preempt();
277 		break;
278 
279 
280 	case EXC_ALI|EXC_USER:
281 		if (fix_unaligned(l, frame) != 0) {
282 			KSI_INIT_TRAP(&ksi);
283 			ksi.ksi_signo = SIGBUS;
284 			ksi.ksi_trap = EXC_ALI;
285 			ksi.ksi_addr = (void *)frame->dar;
286 			trapsignal(l, &ksi);
287 		} else
288 			frame->srr0 += 4;
289 		break;
290 
291 	case EXC_PGM|EXC_USER:
292 		/*
293 		 * Illegal insn:
294 		 *
295 		 * let's try to see if it's FPU and can be emulated.
296 		 */
297 		uvmexp.traps++;
298 		if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) {
299 			memset(&l->l_addr->u_pcb.pcb_fpu, 0,
300 				sizeof l->l_addr->u_pcb.pcb_fpu);
301 			l->l_addr->u_pcb.pcb_flags |= PCB_FPU;
302 		}
303 
304 		if ((rv = fpu_emulate(frame,
305 			(struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) {
306 			KSI_INIT_TRAP(&ksi);
307 			ksi.ksi_signo = rv;
308 			ksi.ksi_trap = EXC_PGM;
309 			ksi.ksi_addr = (void *)frame->srr0;
310 			trapsignal(l, &ksi);
311 		}
312 		break;
313 
314 	case EXC_MCHK:
315 		{
316 			struct faultbuf *fb;
317 
318 			if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) {
319 				frame->tf_xtra[TF_PID] = KERNEL_PID;
320 				frame->srr0 = fb->fb_pc;
321 				frame->srr1 |= PSL_IR; /* Re-enable IMMU */
322 				frame->fixreg[1] = fb->fb_sp;
323 				frame->fixreg[2] = fb->fb_r2;
324 				frame->fixreg[3] = 1; /* Return TRUE */
325 				frame->cr = fb->fb_cr;
326 				memcpy(&frame->fixreg[13], fb->fb_fixreg,
327 				    sizeof(fb->fb_fixreg));
328 				goto done;
329 			}
330 		}
331 		goto brain_damage;
332 	default:
333  brain_damage:
334 		printf("trap type 0x%x at 0x%lx\n", type, frame->srr0);
335 #if defined(DDB) || defined(KGDB)
336 		if (kdb_trap(type, frame))
337 			goto done;
338 #endif
339 #ifdef TRAP_PANICWAIT
340 		printf("Press a key to panic.\n");
341 		cngetc();
342 #endif
343 		panic("trap");
344 	}
345 
346 	/* Invoke MI userret code */
347 	mi_userret(l);
348  done:
349 	return;
350 }
351 
352 int
353 ctx_setup(int ctx, int srr1)
354 {
355 	volatile struct pmap *pm;
356 
357 	/* Update PID if we're returning to user mode. */
358 	if (srr1 & PSL_PR) {
359 		pm = curproc->p_vmspace->vm_map.pmap;
360 		if (!pm->pm_ctx) {
361 			ctx_alloc(__UNVOLATILE(pm));
362 		}
363 		ctx = pm->pm_ctx;
364 		if (srr1 & PSL_SE) {
365 			int dbreg, mask = 0x48000000;
366 				/*
367 				 * Set the Internal Debug and
368 				 * Instruction Completion bits of
369 				 * the DBCR0 register.
370 				 *
371 				 * XXX this is also used by jtag debuggers...
372 				 */
373 			__asm volatile("mfspr %0,0x3f2;"
374 			    "or %0,%0,%1;"
375 			    "mtspr 0x3f2,%0;" :
376 			    "=&r" (dbreg) : "r" (mask));
377 		}
378 	}
379 	else if (!ctx) {
380 		ctx = KERNEL_PID;
381 	}
382 	return (ctx);
383 }
384 
385 /*
386  * Used by copyin()/copyout()
387  */
388 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int));
389 extern void vunmaprange __P((vaddr_t, vsize_t));
390 static int bigcopyin __P((const void *, void *, size_t ));
391 static int bigcopyout __P((const void *, void *, size_t ));
392 
393 int
394 copyin(const void *udaddr, void *kaddr, size_t len)
395 {
396 	struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
397 	int msr, pid, tmp, ctx, count=0;
398 	struct faultbuf env;
399 
400 	/* For bigger buffers use the faster copy */
401 	if (len > 1024)
402 		return (bigcopyin(udaddr, kaddr, len));
403 
404 	if (setfault(&env)) {
405 		curpcb->pcb_onfault = 0;
406 		return EFAULT;
407 	}
408 
409 	if (!(ctx = pm->pm_ctx)) {
410 		/* No context -- assign it one */
411 		ctx_alloc(pm);
412 		ctx = pm->pm_ctx;
413 	}
414 
415 	__asm volatile(
416 		"   mfmsr %[msr];"          /* Save MSR */
417 		"   li %[pid],0x20; "
418 		"   andc %[pid],%[msr],%[pid]; mtmsr %[pid];"   /* Disable IMMU */
419 		"   mfpid %[pid];"          /* Save old PID */
420 		"   sync; isync;"
421 
422 		"   srwi. %[count],%[len],0x2;"     /* How many words? */
423 		"   beq-  2f;"              /* No words. Go do bytes */
424 		"   mtctr %[count];"
425 		"1: mtpid %[ctx]; sync;"
426 		"   lswi %[tmp],%[udaddr],4;"       /* Load user word */
427 		"   addi %[udaddr],%[udaddr],0x4;"  /* next udaddr word */
428 		"   sync; isync;"
429 		"   mtpid %[pid];sync;"
430 		"   stswi %[tmp],%[kaddr],4;"        /* Store kernel word */
431 		"   dcbf 0,%[kaddr];"           /* flush cache */
432 		"   addi %[kaddr],%[kaddr],0x4;"    /* next udaddr word */
433 		"   sync; isync;"
434 		"   bdnz 1b;"               /* repeat */
435 
436 		"2: andi. %[count],%[len],0x3;"     /* How many remaining bytes? */
437 		"   addi %[count],%[count],0x1;"
438 		"   mtctr %[count];"
439 		"3: bdz 10f;"               /* while count */
440 		"   mtpid %[ctx];sync;"
441 		"   lbz %[tmp],0(%[udaddr]);"       /* Load user byte */
442 		"   addi %[udaddr],%[udaddr],0x1;"  /* next udaddr byte */
443 		"   sync; isync;"
444 		"   mtpid %[pid]; sync;"
445 		"   stb %[tmp],0(%[kaddr]);"        /* Store kernel byte */
446 		"   dcbf 0,%[kaddr];"           /* flush cache */
447 		"   addi %[kaddr],%[kaddr],0x1;"
448 		"   sync; isync;"
449 		"   b 3b;"
450 		"10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */
451 		: [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp)
452 		: [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count));
453 
454 	curpcb->pcb_onfault = 0;
455 	return 0;
456 }
457 
458 static int
459 bigcopyin(const void *udaddr, void *kaddr, size_t len)
460 {
461 	const char *up;
462 	char *kp = kaddr;
463 	struct lwp *l = curlwp;
464 	struct proc *p;
465 	int error;
466 
467 	if (!l) {
468 		return EFAULT;
469 	}
470 
471 	p = l->l_proc;
472 
473 	/*
474 	 * Stolen from physio():
475 	 */
476 	uvm_lwp_hold(l);
477 	error = uvm_vslock(p->p_vmspace, __UNCONST(udaddr), len, VM_PROT_READ);
478 	if (error) {
479 		uvm_lwp_rele(l);
480 		return EFAULT;
481 	}
482 	up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ);
483 
484 	memcpy(kp, up, len);
485 	vunmaprange((vaddr_t)up, len);
486 	uvm_vsunlock(p->p_vmspace, __UNCONST(udaddr), len);
487 	uvm_lwp_rele(l);
488 
489 	return 0;
490 }
491 
492 int
493 copyout(const void *kaddr, void *udaddr, size_t len)
494 {
495 	struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
496 	int msr, pid, tmp, ctx, count=0;
497 	struct faultbuf env;
498 
499 	/* For big copies use more efficient routine */
500 	if (len > 1024)
501 		return (bigcopyout(kaddr, udaddr, len));
502 
503 	if (setfault(&env)) {
504 		curpcb->pcb_onfault = 0;
505 		return EFAULT;
506 	}
507 
508 	if (!(ctx = pm->pm_ctx)) {
509 		/* No context -- assign it one */
510 		ctx_alloc(pm);
511 		ctx = pm->pm_ctx;
512 	}
513 
514 	__asm volatile(
515 		"   mfmsr %[msr];"          /* Save MSR */ \
516 		"   li %[pid],0x20; " \
517 		"   andc %[pid],%[msr],%[pid]; mtmsr %[pid];"   /* Disable IMMU */ \
518 		"   mfpid %[pid];"          /* Save old PID */ \
519 		"   sync; isync;"
520 
521 		"   srwi. %[count],%[len],0x2;"     /* How many words? */
522 		"   beq-  2f;"              /* No words. Go do bytes */
523 		"   mtctr %[count];"
524 		"1: mtpid %[pid];sync;"
525 		"   lswi %[tmp],%[kaddr],4;"        /* Load kernel word */
526 		"   addi %[kaddr],%[kaddr],0x4;"    /* next kaddr word */
527 		"   sync; isync;"
528 		"   mtpid %[ctx]; sync;"
529 		"   stswi %[tmp],%[udaddr],4;"       /* Store user word */
530 		"   dcbf 0,%[udaddr];"          /* flush cache */
531 		"   addi %[udaddr],%[udaddr],0x4;"  /* next udaddr word */
532 		"   sync; isync;"
533 		"   bdnz 1b;"               /* repeat */
534 
535 		"2: andi. %[count],%[len],0x3;"     /* How many remaining bytes? */
536 		"   addi %[count],%[count],0x1;"
537 		"   mtctr %[count];"
538 		"3: bdz  10f;"              /* while count */
539 		"   mtpid %[pid];sync;"
540 		"   lbz %[tmp],0(%[kaddr]);"        /* Load kernel byte */
541 		"   addi %[kaddr],%[kaddr],0x1;"    /* next kaddr byte */
542 		"   sync; isync;"
543 		"   mtpid %[ctx]; sync;"
544 		"   stb %[tmp],0(%[udaddr]);"       /* Store user byte */
545 		"   dcbf 0,%[udaddr];"          /* flush cache */
546 		"   addi %[udaddr],%[udaddr],0x1;"
547 		"   sync; isync;"
548 		"   b 3b;"
549 		"10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */
550 		: [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp)
551 		: [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count));
552 
553 	curpcb->pcb_onfault = 0;
554 	return 0;
555 }
556 
557 static int
558 bigcopyout(const void *kaddr, void *udaddr, size_t len)
559 {
560 	char *up;
561 	const char *kp = (const char *)kaddr;
562 	struct lwp *l = curlwp;
563 	struct proc *p;
564 	int error;
565 
566 	if (!l) {
567 		return EFAULT;
568 	}
569 
570 	p = l->l_proc;
571 
572 	/*
573 	 * Stolen from physio():
574 	 */
575 	uvm_lwp_hold(l);
576 	error = uvm_vslock(p->p_vmspace, udaddr, len, VM_PROT_WRITE);
577 	if (error) {
578 		uvm_lwp_rele(l);
579 		return EFAULT;
580 	}
581 	up = (char *)vmaprange(p, (vaddr_t)udaddr, len,
582 	    VM_PROT_READ | VM_PROT_WRITE);
583 
584 	memcpy(up, kp, len);
585 	vunmaprange((vaddr_t)up, len);
586 	uvm_vsunlock(p->p_vmspace, udaddr, len);
587 	uvm_lwp_rele(l);
588 
589 	return 0;
590 }
591 
592 /*
593  * kcopy(const void *src, void *dst, size_t len);
594  *
595  * Copy len bytes from src to dst, aborting if we encounter a fatal
596  * page fault.
597  *
598  * kcopy() _must_ save and restore the old fault handler since it is
599  * called by uiomove(), which may be in the path of servicing a non-fatal
600  * page fault.
601  */
602 int
603 kcopy(const void *src, void *dst, size_t len)
604 {
605 	struct faultbuf env, *oldfault;
606 
607 	oldfault = curpcb->pcb_onfault;
608 	if (setfault(&env)) {
609 		curpcb->pcb_onfault = oldfault;
610 		return EFAULT;
611 	}
612 
613 	memcpy(dst, src, len);
614 
615 	curpcb->pcb_onfault = oldfault;
616 	return 0;
617 }
618 
619 int
620 badaddr(void *addr, size_t size)
621 {
622 
623 	return badaddr_read(addr, size, NULL);
624 }
625 
626 int
627 badaddr_read(void *addr, size_t size, int *rptr)
628 {
629 	struct faultbuf env;
630 	int x;
631 
632 	/* Get rid of any stale machine checks that have been waiting.  */
633 	__asm volatile ("sync; isync");
634 
635 	if (setfault(&env)) {
636 		curpcb->pcb_onfault = 0;
637 		__asm volatile ("sync");
638 		return 1;
639 	}
640 
641 	__asm volatile ("sync");
642 
643 	switch (size) {
644 	case 1:
645 		x = *(volatile int8_t *)addr;
646 		break;
647 	case 2:
648 		x = *(volatile int16_t *)addr;
649 		break;
650 	case 4:
651 		x = *(volatile int32_t *)addr;
652 		break;
653 	default:
654 		panic("badaddr: invalid size (%d)", size);
655 	}
656 
657 	/* Make sure we took the machine check, if we caused one. */
658 	__asm volatile ("sync; isync");
659 
660 	curpcb->pcb_onfault = 0;
661 	__asm volatile ("sync");	/* To be sure. */
662 
663 	/* Use the value to avoid reorder. */
664 	if (rptr)
665 		*rptr = x;
666 
667 	return 0;
668 }
669 
670 /*
671  * For now, this only deals with the particular unaligned access case
672  * that gcc tends to generate.  Eventually it should handle all of the
673  * possibilities that can happen on a 32-bit PowerPC in big-endian mode.
674  */
675 
676 static int
677 fix_unaligned(struct lwp *l, struct trapframe *frame)
678 {
679 
680 	return -1;
681 }
682 
683 /*
684  * Start a new LWP
685  */
686 void
687 startlwp(arg)
688 	void *arg;
689 {
690 	int err;
691 	ucontext_t *uc = arg;
692 	struct lwp *l = curlwp;
693 
694 	err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags);
695 #if DIAGNOSTIC
696 	if (err) {
697 		printf("Error %d from cpu_setmcontext.", err);
698 	}
699 #endif
700 	pool_put(&lwp_uc_pool, uc);
701 
702 	/* Invoke MI userret code */
703 	mi_userret(l);
704 }
705