trap.c revision 1.24 1 /* $NetBSD: trap.c,v 1.24 2005/01/19 11:41:07 simonb 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 1.24 2005/01/19 11:41:07 simonb Exp $");
71
72 #include "opt_altivec.h"
73 #include "opt_ddb.h"
74 #include "opt_ktrace.h"
75 #include "opt_systrace.h"
76 #include "opt_syscall_debug.h"
77
78 #include <sys/param.h>
79 #include <sys/proc.h>
80 #include <sys/reboot.h>
81 #include <sys/syscall.h>
82 #include <sys/systm.h>
83 #include <sys/user.h>
84 #ifdef KTRACE
85 #include <sys/ktrace.h>
86 #endif
87 #include <sys/pool.h>
88 #include <sys/sa.h>
89 #include <sys/savar.h>
90 #ifdef SYSTRACE
91 #include <sys/systrace.h>
92 #endif
93 #include <sys/userret.h>
94
95 #include <uvm/uvm_extern.h>
96
97 #include <dev/cons.h>
98
99 #include <machine/cpu.h>
100 #include <machine/db_machdep.h>
101 #include <machine/fpu.h>
102 #include <machine/frame.h>
103 #include <machine/pcb.h>
104 #include <machine/psl.h>
105 #include <machine/trap.h>
106
107 #include <powerpc/spr.h>
108 #include <powerpc/ibm4xx/pmap.h>
109 #include <powerpc/ibm4xx/tlb.h>
110 #include <powerpc/fpu/fpu_extern.h>
111
112 /* These definitions should probably be somewhere else XXX */
113 #define FIRSTARG 3 /* first argument is in reg 3 */
114 #define NARGREG 8 /* 8 args are in registers */
115 #define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */
116
117 static int fix_unaligned __P((struct lwp *l, struct trapframe *frame));
118
119 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */
120 /* Why are these not defined in a header? */
121 int badaddr __P((void *, size_t));
122 int badaddr_read __P((void *, size_t, int *));
123 int ctx_setup __P((int, int));
124
125 #ifdef DEBUG
126 #define TDB_ALL 0x1
127 int trapdebug = /* TDB_ALL */ 0;
128 #define DBPRINTF(x, y) if (trapdebug & (x)) printf y
129 #else
130 #define DBPRINTF(x, y)
131 #endif
132
133 void
134 trap(struct trapframe *frame)
135 {
136 struct lwp *l = curlwp;
137 struct proc *p = l ? l->l_proc : NULL;
138 int type = frame->exc;
139 int ftype, rv;
140 ksiginfo_t ksi;
141
142 KASSERT(l == 0 || (l->l_stat == LSONPROC));
143
144 if (frame->srr1 & PSL_PR)
145 type |= EXC_USER;
146
147 ftype = VM_PROT_READ;
148
149 DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n",
150 type, frame->srr0, frame, &frame));
151
152 switch (type) {
153 case EXC_DEBUG|EXC_USER:
154 {
155 int srr2, srr3;
156
157 __asm __volatile("mfspr %0,0x3f0" :
158 "=r" (rv), "=r" (srr2), "=r" (srr3) :);
159 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2,
160 srr3);
161 /* XXX fall through or break here?! */
162 }
163 /*
164 * DEBUG intr -- probably single-step.
165 */
166 case EXC_TRC|EXC_USER:
167 frame->srr1 &= ~PSL_SE;
168 KSI_INIT_TRAP(&ksi);
169 ksi.ksi_signo = SIGTRAP;
170 ksi.ksi_trap = EXC_TRC;
171 ksi.ksi_addr = (void *)frame->srr0;
172 KERNEL_PROC_LOCK(l);
173 trapsignal(l, &ksi);
174 KERNEL_PROC_UNLOCK(l);
175 break;
176
177 /*
178 * If we could not find and install appropriate TLB entry, fall through.
179 */
180
181 case EXC_DSI:
182 /* FALLTHROUGH */
183 case EXC_DTMISS:
184 {
185 struct vm_map *map;
186 vaddr_t va;
187 struct faultbuf *fb = NULL;
188
189 KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE);
190 va = frame->dar;
191 if (frame->tf_xtra[TF_PID] == KERNEL_PID) {
192 map = kernel_map;
193 } else {
194 map = &p->p_vmspace->vm_map;
195 if (l->l_flag & L_SA) {
196 l->l_savp->savp_faultaddr = va;
197 l->l_flag |= L_SA_PAGEFAULT;
198 }
199 }
200
201 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ))
202 ftype = VM_PROT_WRITE;
203
204 DBPRINTF(TDB_ALL,
205 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n",
206 frame->srr0,
207 (ftype & VM_PROT_WRITE) ? "write" : "read",
208 (void *)va, frame->tf_xtra[TF_ESR]));
209 rv = uvm_fault(map, trunc_page(va), 0, ftype);
210 KERNEL_UNLOCK();
211 if (map != kernel_map)
212 l->l_flag &= ~L_SA_PAGEFAULT;
213 if (rv == 0)
214 goto done;
215 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) {
216 frame->tf_xtra[TF_PID] = KERNEL_PID;
217 frame->srr0 = fb->fb_pc;
218 frame->srr1 |= PSL_IR; /* Re-enable IMMU */
219 frame->fixreg[1] = fb->fb_sp;
220 frame->fixreg[2] = fb->fb_r2;
221 frame->fixreg[3] = 1; /* Return TRUE */
222 frame->cr = fb->fb_cr;
223 memcpy(&frame->fixreg[13], fb->fb_fixreg,
224 sizeof(fb->fb_fixreg));
225 goto done;
226 }
227 }
228 goto brain_damage;
229
230 case EXC_DSI|EXC_USER:
231 /* FALLTHROUGH */
232 case EXC_DTMISS|EXC_USER:
233 KERNEL_PROC_LOCK(l);
234
235 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ))
236 ftype = VM_PROT_WRITE;
237
238 DBPRINTF(TDB_ALL,
239 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n",
240 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read",
241 frame->dar, frame->tf_xtra[TF_ESR]));
242 KASSERT(l == curlwp && (l->l_stat == LSONPROC));
243 if (l->l_flag & L_SA) {
244 l->l_savp->savp_faultaddr = (vaddr_t)frame->dar;
245 l->l_flag |= L_SA_PAGEFAULT;
246 }
247 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar),
248 0, ftype);
249 if (rv == 0) {
250 l->l_flag &= ~L_SA_PAGEFAULT;
251 KERNEL_PROC_UNLOCK(l);
252 break;
253 }
254 KSI_INIT_TRAP(&ksi);
255 ksi.ksi_signo = SIGSEGV;
256 ksi.ksi_trap = EXC_DSI;
257 ksi.ksi_addr = (void *)frame->dar;
258 if (rv == ENOMEM) {
259 printf("UVM: pid %d (%s) lid %d, uid %d killed: "
260 "out of swap\n",
261 p->p_pid, p->p_comm, l->l_lid,
262 p->p_cred && p->p_ucred ?
263 p->p_ucred->cr_uid : -1);
264 ksi.ksi_signo = SIGKILL;
265 }
266 trapsignal(l, &ksi);
267 l->l_flag &= ~L_SA_PAGEFAULT;
268 KERNEL_PROC_UNLOCK(l);
269 break;
270
271 case EXC_ITMISS|EXC_USER:
272 case EXC_ISI|EXC_USER:
273 KERNEL_PROC_LOCK(l);
274 if (l->l_flag & L_SA) {
275 l->l_savp->savp_faultaddr = (vaddr_t)frame->srr0;
276 l->l_flag |= L_SA_PAGEFAULT;
277 }
278 ftype = VM_PROT_EXECUTE;
279 DBPRINTF(TDB_ALL,
280 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n",
281 frame->srr0, frame));
282 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0),
283 0, ftype);
284 if (rv == 0) {
285 l->l_flag &= ~L_SA_PAGEFAULT;
286 KERNEL_PROC_UNLOCK(l);
287 break;
288 }
289 KSI_INIT_TRAP(&ksi);
290 ksi.ksi_signo = SIGSEGV;
291 ksi.ksi_trap = EXC_ISI;
292 ksi.ksi_addr = (void *)frame->srr0;
293 ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR);
294 trapsignal(l, &ksi);
295 l->l_flag &= ~L_SA_PAGEFAULT;
296 KERNEL_PROC_UNLOCK(l);
297 break;
298
299 case EXC_AST|EXC_USER:
300 curcpu()->ci_astpending = 0; /* we are about to do it */
301 KERNEL_PROC_LOCK(l);
302 uvmexp.softs++;
303 if (p->p_flag & P_OWEUPC) {
304 p->p_flag &= ~P_OWEUPC;
305 ADDUPROF(p);
306 }
307 /* Check whether we are being preempted. */
308 if (curcpu()->ci_want_resched)
309 preempt(0);
310 KERNEL_PROC_UNLOCK(l);
311 break;
312
313
314 case EXC_ALI|EXC_USER:
315 KERNEL_PROC_LOCK(l);
316 if (fix_unaligned(l, frame) != 0) {
317 KSI_INIT_TRAP(&ksi);
318 ksi.ksi_signo = SIGBUS;
319 ksi.ksi_trap = EXC_ALI;
320 ksi.ksi_addr = (void *)frame->dar;
321 trapsignal(l, &ksi);
322 } else
323 frame->srr0 += 4;
324 KERNEL_PROC_UNLOCK(l);
325 break;
326
327 case EXC_PGM|EXC_USER:
328 /*
329 * Illegal insn:
330 *
331 * let's try to see if it's FPU and can be emulated.
332 */
333 uvmexp.traps++;
334 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) {
335 memset(&l->l_addr->u_pcb.pcb_fpu, 0,
336 sizeof l->l_addr->u_pcb.pcb_fpu);
337 l->l_addr->u_pcb.pcb_flags |= PCB_FPU;
338 }
339
340 if ((rv = fpu_emulate(frame,
341 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) {
342 KSI_INIT_TRAP(&ksi);
343 ksi.ksi_signo = rv;
344 ksi.ksi_trap = EXC_PGM;
345 ksi.ksi_addr = (void *)frame->srr0;
346 KERNEL_PROC_LOCK(l);
347 trapsignal(l, &ksi);
348 KERNEL_PROC_UNLOCK(l);
349 }
350 break;
351
352 case EXC_MCHK:
353 {
354 struct faultbuf *fb;
355
356 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) {
357 frame->tf_xtra[TF_PID] = KERNEL_PID;
358 frame->srr0 = fb->fb_pc;
359 frame->srr1 |= PSL_IR; /* Re-enable IMMU */
360 frame->fixreg[1] = fb->fb_sp;
361 frame->fixreg[2] = fb->fb_r2;
362 frame->fixreg[3] = 1; /* Return TRUE */
363 frame->cr = fb->fb_cr;
364 memcpy(&frame->fixreg[13], fb->fb_fixreg,
365 sizeof(fb->fb_fixreg));
366 goto done;
367 }
368 }
369 goto brain_damage;
370 default:
371 brain_damage:
372 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0);
373 #ifdef DDB
374 if (kdb_trap(type, frame))
375 goto done;
376 #endif
377 #ifdef TRAP_PANICWAIT
378 printf("Press a key to panic.\n");
379 cngetc();
380 #endif
381 panic("trap");
382 }
383
384 /* Invoke MI userret code */
385 mi_userret(l);
386
387 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri;
388 done:
389 return;
390 }
391
392 int
393 ctx_setup(int ctx, int srr1)
394 {
395 volatile struct pmap *pm;
396
397 /* Update PID if we're returning to user mode. */
398 if (srr1 & PSL_PR) {
399 pm = curproc->p_vmspace->vm_map.pmap;
400 if (!pm->pm_ctx) {
401 ctx_alloc((struct pmap *)pm);
402 }
403 ctx = pm->pm_ctx;
404 if (srr1 & PSL_SE) {
405 int dbreg, mask = 0x48000000;
406 /*
407 * Set the Internal Debug and
408 * Instruction Completion bits of
409 * the DBCR0 register.
410 *
411 * XXX this is also used by jtag debuggers...
412 */
413 __asm __volatile("mfspr %0,0x3f2;"
414 "or %0,%0,%1;"
415 "mtspr 0x3f2,%0;" :
416 "=&r" (dbreg) : "r" (mask));
417 }
418 }
419 else if (!ctx) {
420 ctx = KERNEL_PID;
421 }
422 return (ctx);
423 }
424
425 /*
426 * Used by copyin()/copyout()
427 */
428 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int));
429 extern void vunmaprange __P((vaddr_t, vsize_t));
430 static int bigcopyin __P((const void *, void *, size_t ));
431 static int bigcopyout __P((const void *, void *, size_t ));
432
433 int
434 copyin(const void *udaddr, void *kaddr, size_t len)
435 {
436 struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
437 int msr, pid, tmp, ctx;
438 struct faultbuf env;
439
440 /* For bigger buffers use the faster copy */
441 if (len > 256) return (bigcopyin(udaddr, kaddr, len));
442
443 if (setfault(&env)) {
444 curpcb->pcb_onfault = 0;
445 return EFAULT;
446 }
447
448 if (!(ctx = pm->pm_ctx)) {
449 /* No context -- assign it one */
450 ctx_alloc(pm);
451 ctx = pm->pm_ctx;
452 }
453
454 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */
455 "mfmsr %0;" /* Save MSR */
456 "li %1,0x20; "
457 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */
458 "mfpid %1;" /* Save old PID */
459 "sync; isync;"
460
461 "1: bdz 2f;" /* while len */
462 "mtpid %3; sync;" /* Load user ctx */
463 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */
464 "sync; isync;"
465 "mtpid %1;sync;"
466 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */
467 "sync; isync;"
468 "b 1b;" /* repeat */
469
470 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */
471 "sync; isync;"
472 : "=&r" (msr), "=&r" (pid), "=&r" (tmp)
473 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len));
474
475 curpcb->pcb_onfault = 0;
476 return 0;
477 }
478
479 static int
480 bigcopyin(const void *udaddr, void *kaddr, size_t len)
481 {
482 const char *up;
483 char *kp = kaddr;
484 struct lwp *l = curlwp;
485 struct proc *p;
486 int error;
487
488 if (!l) {
489 return EFAULT;
490 }
491
492 p = l->l_proc;
493
494 /*
495 * Stolen from physio():
496 */
497 PHOLD(l);
498 error = uvm_vslock(p, (caddr_t)udaddr, len, VM_PROT_READ);
499 if (error) {
500 PRELE(l);
501 return EFAULT;
502 }
503 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ);
504
505 memcpy(kp, up, len);
506 vunmaprange((vaddr_t)up, len);
507 uvm_vsunlock(p, (caddr_t)udaddr, len);
508 PRELE(l);
509
510 return 0;
511 }
512
513 int
514 copyout(const void *kaddr, void *udaddr, size_t len)
515 {
516 struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
517 int msr, pid, tmp, ctx;
518 struct faultbuf env;
519
520 /* For big copies use more efficient routine */
521 if (len > 256) return (bigcopyout(kaddr, udaddr, len));
522
523 if (setfault(&env)) {
524 curpcb->pcb_onfault = 0;
525 return EFAULT;
526 }
527
528 if (!(ctx = pm->pm_ctx)) {
529 /* No context -- assign it one */
530 ctx_alloc(pm);
531 ctx = pm->pm_ctx;
532 }
533
534 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */
535 "mfmsr %0;" /* Save MSR */
536 "li %1,0x20; "
537 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */
538 "mfpid %1;" /* Save old PID */
539 "sync; isync;"
540
541 "1: bdz 2f;" /* while len */
542 "mtpid %1;sync;"
543 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */
544 "sync; isync;"
545 "mtpid %3; sync;" /* Load user ctx */
546 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */
547 "sync; isync;"
548 "b 1b;" /* repeat */
549
550 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */
551 "sync; isync;"
552 : "=&r" (msr), "=&r" (pid), "=&r" (tmp)
553 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len));
554
555 curpcb->pcb_onfault = 0;
556 return 0;
557 }
558
559 static int
560 bigcopyout(const void *kaddr, void *udaddr, size_t len)
561 {
562 char *up;
563 const char *kp = (char *)kaddr;
564 struct lwp *l = curlwp;
565 struct proc *p;
566 int error;
567
568 if (!l) {
569 return EFAULT;
570 }
571
572 p = l->l_proc;
573
574 /*
575 * Stolen from physio():
576 */
577 PHOLD(l);
578 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE);
579 if (error) {
580 PRELE(l);
581 return EFAULT;
582 }
583 up = (char *)vmaprange(p, (vaddr_t)udaddr, len,
584 VM_PROT_READ | VM_PROT_WRITE);
585
586 memcpy(up, kp, len);
587 vunmaprange((vaddr_t)up, len);
588 uvm_vsunlock(p, udaddr, len);
589 PRELE(l);
590
591 return 0;
592 }
593
594 /*
595 * kcopy(const void *src, void *dst, size_t len);
596 *
597 * Copy len bytes from src to dst, aborting if we encounter a fatal
598 * page fault.
599 *
600 * kcopy() _must_ save and restore the old fault handler since it is
601 * called by uiomove(), which may be in the path of servicing a non-fatal
602 * page fault.
603 */
604 int
605 kcopy(const void *src, void *dst, size_t len)
606 {
607 struct faultbuf env, *oldfault;
608
609 oldfault = curpcb->pcb_onfault;
610 if (setfault(&env)) {
611 curpcb->pcb_onfault = oldfault;
612 return EFAULT;
613 }
614
615 memcpy(dst, src, len);
616
617 curpcb->pcb_onfault = oldfault;
618 return 0;
619 }
620
621 int
622 badaddr(void *addr, size_t size)
623 {
624
625 return badaddr_read(addr, size, NULL);
626 }
627
628 int
629 badaddr_read(void *addr, size_t size, int *rptr)
630 {
631 struct faultbuf env;
632 int x;
633
634 /* Get rid of any stale machine checks that have been waiting. */
635 __asm __volatile ("sync; isync");
636
637 if (setfault(&env)) {
638 curpcb->pcb_onfault = 0;
639 __asm __volatile ("sync");
640 return 1;
641 }
642
643 __asm __volatile ("sync");
644
645 switch (size) {
646 case 1:
647 x = *(volatile int8_t *)addr;
648 break;
649 case 2:
650 x = *(volatile int16_t *)addr;
651 break;
652 case 4:
653 x = *(volatile int32_t *)addr;
654 break;
655 default:
656 panic("badaddr: invalid size (%d)", size);
657 }
658
659 /* Make sure we took the machine check, if we caused one. */
660 __asm __volatile ("sync; isync");
661
662 curpcb->pcb_onfault = 0;
663 __asm __volatile ("sync"); /* To be sure. */
664
665 /* Use the value to avoid reorder. */
666 if (rptr)
667 *rptr = x;
668
669 return 0;
670 }
671
672 /*
673 * For now, this only deals with the particular unaligned access case
674 * that gcc tends to generate. Eventually it should handle all of the
675 * possibilities that can happen on a 32-bit PowerPC in big-endian mode.
676 */
677
678 static int
679 fix_unaligned(struct lwp *l, struct trapframe *frame)
680 {
681
682 return -1;
683 }
684
685 /*
686 * Start a new LWP
687 */
688 void
689 startlwp(arg)
690 void *arg;
691 {
692 int err;
693 ucontext_t *uc = arg;
694 struct lwp *l = curlwp;
695
696 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags);
697 #if DIAGNOSTIC
698 if (err) {
699 printf("Error %d from cpu_setmcontext.", err);
700 }
701 #endif
702 pool_put(&lwp_uc_pool, uc);
703
704 upcallret(l);
705 }
706
707 /*
708 * XXX This is a terrible name.
709 */
710 void
711 upcallret(l)
712 struct lwp *l;
713 {
714
715 /* Invoke MI userret code */
716 mi_userret(l);
717
718 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri;
719 }
720