trap.c revision 1.33 1 /* $NetBSD: trap.c,v 1.33 2006/05/14 21:56:32 elad 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 1.33 2006/05/14 21:56:32 elad Exp $");
71
72 #include "opt_altivec.h"
73 #include "opt_ddb.h"
74
75 #include <sys/param.h>
76 #include <sys/proc.h>
77 #include <sys/reboot.h>
78 #include <sys/syscall.h>
79 #include <sys/systm.h>
80 #include <sys/user.h>
81 #include <sys/pool.h>
82 #include <sys/sa.h>
83 #include <sys/savar.h>
84 #include <sys/userret.h>
85
86 #include <uvm/uvm_extern.h>
87
88 #include <dev/cons.h>
89
90 #include <machine/cpu.h>
91 #include <machine/db_machdep.h>
92 #include <machine/fpu.h>
93 #include <machine/frame.h>
94 #include <machine/pcb.h>
95 #include <machine/psl.h>
96 #include <machine/trap.h>
97
98 #include <powerpc/spr.h>
99 #include <powerpc/ibm4xx/pmap.h>
100 #include <powerpc/ibm4xx/tlb.h>
101 #include <powerpc/fpu/fpu_extern.h>
102
103 /* These definitions should probably be somewhere else XXX */
104 #define FIRSTARG 3 /* first argument is in reg 3 */
105 #define NARGREG 8 /* 8 args are in registers */
106 #define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */
107
108 static int fix_unaligned __P((struct lwp *l, struct trapframe *frame));
109
110 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */
111 /* Why are these not defined in a header? */
112 int badaddr __P((void *, size_t));
113 int badaddr_read __P((void *, size_t, int *));
114 int ctx_setup __P((int, int));
115
116 #ifdef DEBUG
117 #define TDB_ALL 0x1
118 int trapdebug = /* TDB_ALL */ 0;
119 #define DBPRINTF(x, y) if (trapdebug & (x)) printf y
120 #else
121 #define DBPRINTF(x, y)
122 #endif
123
124 void
125 trap(struct trapframe *frame)
126 {
127 struct lwp *l = curlwp;
128 struct proc *p = l ? l->l_proc : NULL;
129 int type = frame->exc;
130 int ftype, rv;
131 ksiginfo_t ksi;
132
133 KASSERT(l == 0 || (l->l_stat == LSONPROC));
134
135 if (frame->srr1 & PSL_PR)
136 type |= EXC_USER;
137
138 ftype = VM_PROT_READ;
139
140 DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n",
141 type, frame->srr0, frame, &frame));
142
143 switch (type) {
144 case EXC_DEBUG|EXC_USER:
145 {
146 int srr2, srr3;
147
148 __asm volatile("mfspr %0,0x3f0" :
149 "=r" (rv), "=r" (srr2), "=r" (srr3) :);
150 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2,
151 srr3);
152 /* XXX fall through or break here?! */
153 }
154 /*
155 * DEBUG intr -- probably single-step.
156 */
157 case EXC_TRC|EXC_USER:
158 frame->srr1 &= ~PSL_SE;
159 KSI_INIT_TRAP(&ksi);
160 ksi.ksi_signo = SIGTRAP;
161 ksi.ksi_trap = EXC_TRC;
162 ksi.ksi_addr = (void *)frame->srr0;
163 KERNEL_PROC_LOCK(l);
164 trapsignal(l, &ksi);
165 KERNEL_PROC_UNLOCK(l);
166 break;
167
168 /*
169 * If we could not find and install appropriate TLB entry, fall through.
170 */
171
172 case EXC_DSI:
173 /* FALLTHROUGH */
174 case EXC_DTMISS:
175 {
176 struct vm_map *map;
177 vaddr_t va;
178 struct faultbuf *fb = NULL;
179
180 KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE);
181 va = frame->dar;
182 if (frame->tf_xtra[TF_PID] == KERNEL_PID) {
183 map = kernel_map;
184 } else {
185 map = &p->p_vmspace->vm_map;
186 if (l->l_flag & L_SA) {
187 l->l_savp->savp_faultaddr = va;
188 l->l_flag |= L_SA_PAGEFAULT;
189 }
190 }
191
192 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ))
193 ftype = VM_PROT_WRITE;
194
195 DBPRINTF(TDB_ALL,
196 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n",
197 frame->srr0,
198 (ftype & VM_PROT_WRITE) ? "write" : "read",
199 (void *)va, frame->tf_xtra[TF_ESR]));
200 rv = uvm_fault(map, trunc_page(va), ftype);
201 KERNEL_UNLOCK();
202 if (map != kernel_map)
203 l->l_flag &= ~L_SA_PAGEFAULT;
204 if (rv == 0)
205 goto done;
206 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) {
207 frame->tf_xtra[TF_PID] = KERNEL_PID;
208 frame->srr0 = fb->fb_pc;
209 frame->srr1 |= PSL_IR; /* Re-enable IMMU */
210 frame->fixreg[1] = fb->fb_sp;
211 frame->fixreg[2] = fb->fb_r2;
212 frame->fixreg[3] = 1; /* Return TRUE */
213 frame->cr = fb->fb_cr;
214 memcpy(&frame->fixreg[13], fb->fb_fixreg,
215 sizeof(fb->fb_fixreg));
216 goto done;
217 }
218 }
219 goto brain_damage;
220
221 case EXC_DSI|EXC_USER:
222 /* FALLTHROUGH */
223 case EXC_DTMISS|EXC_USER:
224 KERNEL_PROC_LOCK(l);
225
226 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ))
227 ftype = VM_PROT_WRITE;
228
229 DBPRINTF(TDB_ALL,
230 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n",
231 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read",
232 frame->dar, frame->tf_xtra[TF_ESR]));
233 KASSERT(l == curlwp && (l->l_stat == LSONPROC));
234 if (l->l_flag & L_SA) {
235 l->l_savp->savp_faultaddr = (vaddr_t)frame->dar;
236 l->l_flag |= L_SA_PAGEFAULT;
237 }
238 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar),
239 ftype);
240 if (rv == 0) {
241 l->l_flag &= ~L_SA_PAGEFAULT;
242 KERNEL_PROC_UNLOCK(l);
243 break;
244 }
245 KSI_INIT_TRAP(&ksi);
246 ksi.ksi_signo = SIGSEGV;
247 ksi.ksi_trap = EXC_DSI;
248 ksi.ksi_addr = (void *)frame->dar;
249 if (rv == ENOMEM) {
250 printf("UVM: pid %d (%s) lid %d, uid %d killed: "
251 "out of swap\n",
252 p->p_pid, p->p_comm, l->l_lid,
253 p->p_cred ?
254 kauth_cred_geteuid(p->p_cred) : -1);
255 ksi.ksi_signo = SIGKILL;
256 }
257 trapsignal(l, &ksi);
258 l->l_flag &= ~L_SA_PAGEFAULT;
259 KERNEL_PROC_UNLOCK(l);
260 break;
261
262 case EXC_ITMISS|EXC_USER:
263 case EXC_ISI|EXC_USER:
264 KERNEL_PROC_LOCK(l);
265 if (l->l_flag & L_SA) {
266 l->l_savp->savp_faultaddr = (vaddr_t)frame->srr0;
267 l->l_flag |= L_SA_PAGEFAULT;
268 }
269 ftype = VM_PROT_EXECUTE;
270 DBPRINTF(TDB_ALL,
271 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n",
272 frame->srr0, frame));
273 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0),
274 ftype);
275 if (rv == 0) {
276 l->l_flag &= ~L_SA_PAGEFAULT;
277 KERNEL_PROC_UNLOCK(l);
278 break;
279 }
280 KSI_INIT_TRAP(&ksi);
281 ksi.ksi_signo = SIGSEGV;
282 ksi.ksi_trap = EXC_ISI;
283 ksi.ksi_addr = (void *)frame->srr0;
284 ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR);
285 trapsignal(l, &ksi);
286 l->l_flag &= ~L_SA_PAGEFAULT;
287 KERNEL_PROC_UNLOCK(l);
288 break;
289
290 case EXC_AST|EXC_USER:
291 curcpu()->ci_astpending = 0; /* we are about to do it */
292 KERNEL_PROC_LOCK(l);
293 uvmexp.softs++;
294 if (p->p_flag & P_OWEUPC) {
295 p->p_flag &= ~P_OWEUPC;
296 ADDUPROF(p);
297 }
298 /* Check whether we are being preempted. */
299 if (curcpu()->ci_want_resched)
300 preempt(0);
301 KERNEL_PROC_UNLOCK(l);
302 break;
303
304
305 case EXC_ALI|EXC_USER:
306 KERNEL_PROC_LOCK(l);
307 if (fix_unaligned(l, frame) != 0) {
308 KSI_INIT_TRAP(&ksi);
309 ksi.ksi_signo = SIGBUS;
310 ksi.ksi_trap = EXC_ALI;
311 ksi.ksi_addr = (void *)frame->dar;
312 trapsignal(l, &ksi);
313 } else
314 frame->srr0 += 4;
315 KERNEL_PROC_UNLOCK(l);
316 break;
317
318 case EXC_PGM|EXC_USER:
319 /*
320 * Illegal insn:
321 *
322 * let's try to see if it's FPU and can be emulated.
323 */
324 uvmexp.traps++;
325 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) {
326 memset(&l->l_addr->u_pcb.pcb_fpu, 0,
327 sizeof l->l_addr->u_pcb.pcb_fpu);
328 l->l_addr->u_pcb.pcb_flags |= PCB_FPU;
329 }
330
331 if ((rv = fpu_emulate(frame,
332 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) {
333 KSI_INIT_TRAP(&ksi);
334 ksi.ksi_signo = rv;
335 ksi.ksi_trap = EXC_PGM;
336 ksi.ksi_addr = (void *)frame->srr0;
337 KERNEL_PROC_LOCK(l);
338 trapsignal(l, &ksi);
339 KERNEL_PROC_UNLOCK(l);
340 }
341 break;
342
343 case EXC_MCHK:
344 {
345 struct faultbuf *fb;
346
347 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) {
348 frame->tf_xtra[TF_PID] = KERNEL_PID;
349 frame->srr0 = fb->fb_pc;
350 frame->srr1 |= PSL_IR; /* Re-enable IMMU */
351 frame->fixreg[1] = fb->fb_sp;
352 frame->fixreg[2] = fb->fb_r2;
353 frame->fixreg[3] = 1; /* Return TRUE */
354 frame->cr = fb->fb_cr;
355 memcpy(&frame->fixreg[13], fb->fb_fixreg,
356 sizeof(fb->fb_fixreg));
357 goto done;
358 }
359 }
360 goto brain_damage;
361 default:
362 brain_damage:
363 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0);
364 #ifdef DDB
365 if (kdb_trap(type, frame))
366 goto done;
367 #endif
368 #ifdef TRAP_PANICWAIT
369 printf("Press a key to panic.\n");
370 cngetc();
371 #endif
372 panic("trap");
373 }
374
375 /* Invoke MI userret code */
376 mi_userret(l);
377
378 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri;
379 done:
380 return;
381 }
382
383 int
384 ctx_setup(int ctx, int srr1)
385 {
386 volatile struct pmap *pm;
387
388 /* Update PID if we're returning to user mode. */
389 if (srr1 & PSL_PR) {
390 pm = curproc->p_vmspace->vm_map.pmap;
391 if (!pm->pm_ctx) {
392 ctx_alloc(__UNVOLATILE(pm));
393 }
394 ctx = pm->pm_ctx;
395 if (srr1 & PSL_SE) {
396 int dbreg, mask = 0x48000000;
397 /*
398 * Set the Internal Debug and
399 * Instruction Completion bits of
400 * the DBCR0 register.
401 *
402 * XXX this is also used by jtag debuggers...
403 */
404 __asm volatile("mfspr %0,0x3f2;"
405 "or %0,%0,%1;"
406 "mtspr 0x3f2,%0;" :
407 "=&r" (dbreg) : "r" (mask));
408 }
409 }
410 else if (!ctx) {
411 ctx = KERNEL_PID;
412 }
413 return (ctx);
414 }
415
416 /*
417 * Used by copyin()/copyout()
418 */
419 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int));
420 extern void vunmaprange __P((vaddr_t, vsize_t));
421 static int bigcopyin __P((const void *, void *, size_t ));
422 static int bigcopyout __P((const void *, void *, size_t ));
423
424 int
425 copyin(const void *udaddr, void *kaddr, size_t len)
426 {
427 struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
428 int msr, pid, tmp, ctx;
429 struct faultbuf env;
430
431 /* For bigger buffers use the faster copy */
432 if (len > 256)
433 return (bigcopyin(udaddr, kaddr, len));
434
435 if (setfault(&env)) {
436 curpcb->pcb_onfault = 0;
437 return EFAULT;
438 }
439
440 if (!(ctx = pm->pm_ctx)) {
441 /* No context -- assign it one */
442 ctx_alloc(pm);
443 ctx = pm->pm_ctx;
444 }
445
446 __asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */
447 "mfmsr %0;" /* Save MSR */
448 "li %1,0x20; "
449 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */
450 "mfpid %1;" /* Save old PID */
451 "sync; isync;"
452
453 "1: bdz 2f;" /* while len */
454 "mtpid %3; sync;" /* Load user ctx */
455 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */
456 "sync; isync;"
457 "mtpid %1;sync;"
458 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */
459 "sync; isync;"
460 "b 1b;" /* repeat */
461
462 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */
463 "sync; isync;"
464 : "=&r" (msr), "=&r" (pid), "=&r" (tmp)
465 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len));
466
467 curpcb->pcb_onfault = 0;
468 return 0;
469 }
470
471 static int
472 bigcopyin(const void *udaddr, void *kaddr, size_t len)
473 {
474 const char *up;
475 char *kp = kaddr;
476 struct lwp *l = curlwp;
477 struct proc *p;
478 int error;
479
480 if (!l) {
481 return EFAULT;
482 }
483
484 p = l->l_proc;
485
486 /*
487 * Stolen from physio():
488 */
489 PHOLD(l);
490 error = uvm_vslock(p, __UNCONST(udaddr), len, VM_PROT_READ);
491 if (error) {
492 PRELE(l);
493 return EFAULT;
494 }
495 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ);
496
497 memcpy(kp, up, len);
498 vunmaprange((vaddr_t)up, len);
499 uvm_vsunlock(p, __UNCONST(udaddr), len);
500 PRELE(l);
501
502 return 0;
503 }
504
505 int
506 copyout(const void *kaddr, void *udaddr, size_t len)
507 {
508 struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
509 int msr, pid, tmp, ctx;
510 struct faultbuf env;
511
512 /* For big copies use more efficient routine */
513 if (len > 256)
514 return (bigcopyout(kaddr, udaddr, len));
515
516 if (setfault(&env)) {
517 curpcb->pcb_onfault = 0;
518 return EFAULT;
519 }
520
521 if (!(ctx = pm->pm_ctx)) {
522 /* No context -- assign it one */
523 ctx_alloc(pm);
524 ctx = pm->pm_ctx;
525 }
526
527 __asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */
528 "mfmsr %0;" /* Save MSR */
529 "li %1,0x20; "
530 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */
531 "mfpid %1;" /* Save old PID */
532 "sync; isync;"
533
534 "1: bdz 2f;" /* while len */
535 "mtpid %1;sync;"
536 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */
537 "sync; isync;"
538 "mtpid %3; sync;" /* Load user ctx */
539 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */
540 "sync; isync;"
541 "b 1b;" /* repeat */
542
543 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */
544 "sync; isync;"
545 : "=&r" (msr), "=&r" (pid), "=&r" (tmp)
546 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len));
547
548 curpcb->pcb_onfault = 0;
549 return 0;
550 }
551
552 static int
553 bigcopyout(const void *kaddr, void *udaddr, size_t len)
554 {
555 char *up;
556 const char *kp = (const char *)kaddr;
557 struct lwp *l = curlwp;
558 struct proc *p;
559 int error;
560
561 if (!l) {
562 return EFAULT;
563 }
564
565 p = l->l_proc;
566
567 /*
568 * Stolen from physio():
569 */
570 PHOLD(l);
571 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE);
572 if (error) {
573 PRELE(l);
574 return EFAULT;
575 }
576 up = (char *)vmaprange(p, (vaddr_t)udaddr, len,
577 VM_PROT_READ | VM_PROT_WRITE);
578
579 memcpy(up, kp, len);
580 vunmaprange((vaddr_t)up, len);
581 uvm_vsunlock(p, udaddr, len);
582 PRELE(l);
583
584 return 0;
585 }
586
587 /*
588 * kcopy(const void *src, void *dst, size_t len);
589 *
590 * Copy len bytes from src to dst, aborting if we encounter a fatal
591 * page fault.
592 *
593 * kcopy() _must_ save and restore the old fault handler since it is
594 * called by uiomove(), which may be in the path of servicing a non-fatal
595 * page fault.
596 */
597 int
598 kcopy(const void *src, void *dst, size_t len)
599 {
600 struct faultbuf env, *oldfault;
601
602 oldfault = curpcb->pcb_onfault;
603 if (setfault(&env)) {
604 curpcb->pcb_onfault = oldfault;
605 return EFAULT;
606 }
607
608 memcpy(dst, src, len);
609
610 curpcb->pcb_onfault = oldfault;
611 return 0;
612 }
613
614 int
615 badaddr(void *addr, size_t size)
616 {
617
618 return badaddr_read(addr, size, NULL);
619 }
620
621 int
622 badaddr_read(void *addr, size_t size, int *rptr)
623 {
624 struct faultbuf env;
625 int x;
626
627 /* Get rid of any stale machine checks that have been waiting. */
628 __asm volatile ("sync; isync");
629
630 if (setfault(&env)) {
631 curpcb->pcb_onfault = 0;
632 __asm volatile ("sync");
633 return 1;
634 }
635
636 __asm volatile ("sync");
637
638 switch (size) {
639 case 1:
640 x = *(volatile int8_t *)addr;
641 break;
642 case 2:
643 x = *(volatile int16_t *)addr;
644 break;
645 case 4:
646 x = *(volatile int32_t *)addr;
647 break;
648 default:
649 panic("badaddr: invalid size (%d)", size);
650 }
651
652 /* Make sure we took the machine check, if we caused one. */
653 __asm volatile ("sync; isync");
654
655 curpcb->pcb_onfault = 0;
656 __asm volatile ("sync"); /* To be sure. */
657
658 /* Use the value to avoid reorder. */
659 if (rptr)
660 *rptr = x;
661
662 return 0;
663 }
664
665 /*
666 * For now, this only deals with the particular unaligned access case
667 * that gcc tends to generate. Eventually it should handle all of the
668 * possibilities that can happen on a 32-bit PowerPC in big-endian mode.
669 */
670
671 static int
672 fix_unaligned(struct lwp *l, struct trapframe *frame)
673 {
674
675 return -1;
676 }
677
678 /*
679 * Start a new LWP
680 */
681 void
682 startlwp(arg)
683 void *arg;
684 {
685 int err;
686 ucontext_t *uc = arg;
687 struct lwp *l = curlwp;
688
689 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags);
690 #if DIAGNOSTIC
691 if (err) {
692 printf("Error %d from cpu_setmcontext.", err);
693 }
694 #endif
695 pool_put(&lwp_uc_pool, uc);
696
697 upcallret(l);
698 }
699
700 /*
701 * XXX This is a terrible name.
702 */
703 void
704 upcallret(l)
705 struct lwp *l;
706 {
707
708 /* Invoke MI userret code */
709 mi_userret(l);
710
711 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri;
712 }
713