1 /*
2 * linux/arch/m68k/kernel/signal.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file COPYING in the main directory of this archive
8 * for more details.
9 */
10
11 /*
12 * Linux/m68k support by Hamish Macdonald
13 *
14 * 68060 fixes by Jesper Skov
15 *
16 * 1997-12-01 Modified for POSIX.1b signals by Andreas Schwab
17 *
18 * mathemu support by Roman Zippel
19 * (Note: fpstate in the signal context is completely ignored for the emulator
20 * and the internal floating point format is put on stack)
21 */
22
23 /*
24 * ++roman (07/09/96): implemented signal stacks (specially for tosemu on
25 * Atari :-) Current limitation: Only one sigstack can be active at one time.
26 * If a second signal with SA_ONSTACK set arrives while working on a sigstack,
27 * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested
28 * signal handlers!
29 */
30
31 #include <linux/sched.h>
32 #include <linux/mm.h>
33 #include <linux/kernel.h>
34 #include <linux/signal.h>
35 #include <linux/syscalls.h>
36 #include <linux/errno.h>
37 #include <linux/wait.h>
38 #include <linux/ptrace.h>
39 #include <linux/unistd.h>
40 #include <linux/stddef.h>
41 #include <linux/highuid.h>
42 #include <linux/personality.h>
43 #include <linux/tty.h>
44 #include <linux/binfmts.h>
45 #include <linux/extable.h>
46 #include <linux/tracehook.h>
47
48 #include <asm/setup.h>
49 #include <asm/uaccess.h>
50 #include <asm/pgtable.h>
51 #include <asm/traps.h>
52 #include <asm/ucontext.h>
53 #include <asm/cacheflush.h>
54
55 #ifdef CONFIG_MMU
56
57 /*
58 * Handle the slight differences in classic 68k and ColdFire trap frames.
59 */
60 #ifdef CONFIG_COLDFIRE
61 #define FORMAT 4
62 #define FMT4SIZE 0
63 #else
64 #define FORMAT 0
65 #define FMT4SIZE sizeof(((struct frame *)0)->un.fmt4)
66 #endif
67
68 static const int frame_size_change[16] = {
69 [1] = -1, /* sizeof(((struct frame *)0)->un.fmt1), */
70 [2] = sizeof(((struct frame *)0)->un.fmt2),
71 [3] = sizeof(((struct frame *)0)->un.fmt3),
72 [4] = FMT4SIZE,
73 [5] = -1, /* sizeof(((struct frame *)0)->un.fmt5), */
74 [6] = -1, /* sizeof(((struct frame *)0)->un.fmt6), */
75 [7] = sizeof(((struct frame *)0)->un.fmt7),
76 [8] = -1, /* sizeof(((struct frame *)0)->un.fmt8), */
77 [9] = sizeof(((struct frame *)0)->un.fmt9),
78 [10] = sizeof(((struct frame *)0)->un.fmta),
79 [11] = sizeof(((struct frame *)0)->un.fmtb),
80 [12] = -1, /* sizeof(((struct frame *)0)->un.fmtc), */
81 [13] = -1, /* sizeof(((struct frame *)0)->un.fmtd), */
82 [14] = -1, /* sizeof(((struct frame *)0)->un.fmte), */
83 [15] = -1, /* sizeof(((struct frame *)0)->un.fmtf), */
84 };
85
frame_extra_sizes(int f)86 static inline int frame_extra_sizes(int f)
87 {
88 return frame_size_change[f];
89 }
90
handle_kernel_fault(struct pt_regs * regs)91 int handle_kernel_fault(struct pt_regs *regs)
92 {
93 const struct exception_table_entry *fixup;
94 struct pt_regs *tregs;
95
96 /* Are we prepared to handle this kernel fault? */
97 fixup = search_exception_tables(regs->pc);
98 if (!fixup)
99 return 0;
100
101 /* Create a new four word stack frame, discarding the old one. */
102 regs->stkadj = frame_extra_sizes(regs->format);
103 tregs = (struct pt_regs *)((long)regs + regs->stkadj);
104 tregs->vector = regs->vector;
105 tregs->format = FORMAT;
106 tregs->pc = fixup->fixup;
107 tregs->sr = regs->sr;
108
109 return 1;
110 }
111
ptrace_signal_deliver(void)112 void ptrace_signal_deliver(void)
113 {
114 struct pt_regs *regs = signal_pt_regs();
115 if (regs->orig_d0 < 0)
116 return;
117 switch (regs->d0) {
118 case -ERESTARTNOHAND:
119 case -ERESTARTSYS:
120 case -ERESTARTNOINTR:
121 regs->d0 = regs->orig_d0;
122 regs->orig_d0 = -1;
123 regs->pc -= 2;
124 break;
125 }
126 }
127
push_cache(unsigned long vaddr)128 static inline void push_cache (unsigned long vaddr)
129 {
130 /*
131 * Using the old cache_push_v() was really a big waste.
132 *
133 * What we are trying to do is to flush 8 bytes to ram.
134 * Flushing 2 cache lines of 16 bytes is much cheaper than
135 * flushing 1 or 2 pages, as previously done in
136 * cache_push_v().
137 * Jes
138 */
139 if (CPU_IS_040) {
140 unsigned long temp;
141
142 __asm__ __volatile__ (".chip 68040\n\t"
143 "nop\n\t"
144 "ptestr (%1)\n\t"
145 "movec %%mmusr,%0\n\t"
146 ".chip 68k"
147 : "=r" (temp)
148 : "a" (vaddr));
149
150 temp &= PAGE_MASK;
151 temp |= vaddr & ~PAGE_MASK;
152
153 __asm__ __volatile__ (".chip 68040\n\t"
154 "nop\n\t"
155 "cpushl %%bc,(%0)\n\t"
156 ".chip 68k"
157 : : "a" (temp));
158 }
159 else if (CPU_IS_060) {
160 unsigned long temp;
161 __asm__ __volatile__ (".chip 68060\n\t"
162 "plpar (%0)\n\t"
163 ".chip 68k"
164 : "=a" (temp)
165 : "0" (vaddr));
166 __asm__ __volatile__ (".chip 68060\n\t"
167 "cpushl %%bc,(%0)\n\t"
168 ".chip 68k"
169 : : "a" (temp));
170 } else if (!CPU_IS_COLDFIRE) {
171 /*
172 * 68030/68020 have no writeback cache;
173 * still need to clear icache.
174 * Note that vaddr is guaranteed to be long word aligned.
175 */
176 unsigned long temp;
177 asm volatile ("movec %%cacr,%0" : "=r" (temp));
178 temp += 4;
179 asm volatile ("movec %0,%%caar\n\t"
180 "movec %1,%%cacr"
181 : : "r" (vaddr), "r" (temp));
182 asm volatile ("movec %0,%%caar\n\t"
183 "movec %1,%%cacr"
184 : : "r" (vaddr + 4), "r" (temp));
185 } else {
186 /* CPU_IS_COLDFIRE */
187 #if defined(CONFIG_CACHE_COPYBACK)
188 flush_cf_dcache(0, DCACHE_MAX_ADDR);
189 #endif
190 /* Invalidate instruction cache for the pushed bytes */
191 clear_cf_icache(vaddr, vaddr + 8);
192 }
193 }
194
adjustformat(struct pt_regs * regs)195 static inline void adjustformat(struct pt_regs *regs)
196 {
197 }
198
save_a5_state(struct sigcontext * sc,struct pt_regs * regs)199 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs)
200 {
201 }
202
203 #else /* CONFIG_MMU */
204
205 void ret_from_user_signal(void);
206 void ret_from_user_rt_signal(void);
207
frame_extra_sizes(int f)208 static inline int frame_extra_sizes(int f)
209 {
210 /* No frame size adjustments required on non-MMU CPUs */
211 return 0;
212 }
213
adjustformat(struct pt_regs * regs)214 static inline void adjustformat(struct pt_regs *regs)
215 {
216 /*
217 * set format byte to make stack appear modulo 4, which it will
218 * be when doing the rte
219 */
220 regs->format = 0x4;
221 }
222
save_a5_state(struct sigcontext * sc,struct pt_regs * regs)223 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs)
224 {
225 sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5;
226 }
227
push_cache(unsigned long vaddr)228 static inline void push_cache(unsigned long vaddr)
229 {
230 }
231
232 #endif /* CONFIG_MMU */
233
234 /*
235 * Do a signal return; undo the signal stack.
236 *
237 * Keep the return code on the stack quadword aligned!
238 * That makes the cache flush below easier.
239 */
240
241 struct sigframe
242 {
243 char __user *pretcode;
244 int sig;
245 int code;
246 struct sigcontext __user *psc;
247 char retcode[8];
248 unsigned long extramask[_NSIG_WORDS-1];
249 struct sigcontext sc;
250 };
251
252 struct rt_sigframe
253 {
254 char __user *pretcode;
255 int sig;
256 struct siginfo __user *pinfo;
257 void __user *puc;
258 char retcode[8];
259 struct siginfo info;
260 struct ucontext uc;
261 };
262
263 #define FPCONTEXT_SIZE 216
264 #define uc_fpstate uc_filler[0]
265 #define uc_formatvec uc_filler[FPCONTEXT_SIZE/4]
266 #define uc_extra uc_filler[FPCONTEXT_SIZE/4+1]
267
268 #ifdef CONFIG_FPU
269
270 static unsigned char fpu_version; /* version number of fpu, set by setup_frame */
271
restore_fpu_state(struct sigcontext * sc)272 static inline int restore_fpu_state(struct sigcontext *sc)
273 {
274 int err = 1;
275
276 if (FPU_IS_EMU) {
277 /* restore registers */
278 memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12);
279 memcpy(current->thread.fp, sc->sc_fpregs, 24);
280 return 0;
281 }
282
283 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
284 /* Verify the frame format. */
285 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) &&
286 (sc->sc_fpstate[0] != fpu_version))
287 goto out;
288 if (CPU_IS_020_OR_030) {
289 if (m68k_fputype & FPU_68881 &&
290 !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4))
291 goto out;
292 if (m68k_fputype & FPU_68882 &&
293 !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4))
294 goto out;
295 } else if (CPU_IS_040) {
296 if (!(sc->sc_fpstate[1] == 0x00 ||
297 sc->sc_fpstate[1] == 0x28 ||
298 sc->sc_fpstate[1] == 0x60))
299 goto out;
300 } else if (CPU_IS_060) {
301 if (!(sc->sc_fpstate[3] == 0x00 ||
302 sc->sc_fpstate[3] == 0x60 ||
303 sc->sc_fpstate[3] == 0xe0))
304 goto out;
305 } else if (CPU_IS_COLDFIRE) {
306 if (!(sc->sc_fpstate[0] == 0x00 ||
307 sc->sc_fpstate[0] == 0x05 ||
308 sc->sc_fpstate[0] == 0xe5))
309 goto out;
310 } else
311 goto out;
312
313 if (CPU_IS_COLDFIRE) {
314 __asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t"
315 "fmovel %1,%%fpcr\n\t"
316 "fmovel %2,%%fpsr\n\t"
317 "fmovel %3,%%fpiar"
318 : /* no outputs */
319 : "m" (sc->sc_fpregs[0]),
320 "m" (sc->sc_fpcntl[0]),
321 "m" (sc->sc_fpcntl[1]),
322 "m" (sc->sc_fpcntl[2]));
323 } else {
324 __asm__ volatile (".chip 68k/68881\n\t"
325 "fmovemx %0,%%fp0-%%fp1\n\t"
326 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
327 ".chip 68k"
328 : /* no outputs */
329 : "m" (*sc->sc_fpregs),
330 "m" (*sc->sc_fpcntl));
331 }
332 }
333
334 if (CPU_IS_COLDFIRE) {
335 __asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate));
336 } else {
337 __asm__ volatile (".chip 68k/68881\n\t"
338 "frestore %0\n\t"
339 ".chip 68k"
340 : : "m" (*sc->sc_fpstate));
341 }
342 err = 0;
343
344 out:
345 return err;
346 }
347
rt_restore_fpu_state(struct ucontext __user * uc)348 static inline int rt_restore_fpu_state(struct ucontext __user *uc)
349 {
350 unsigned char fpstate[FPCONTEXT_SIZE];
351 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0);
352 fpregset_t fpregs;
353 int err = 1;
354
355 if (FPU_IS_EMU) {
356 /* restore fpu control register */
357 if (__copy_from_user(current->thread.fpcntl,
358 uc->uc_mcontext.fpregs.f_fpcntl, 12))
359 goto out;
360 /* restore all other fpu register */
361 if (__copy_from_user(current->thread.fp,
362 uc->uc_mcontext.fpregs.f_fpregs, 96))
363 goto out;
364 return 0;
365 }
366
367 if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate))
368 goto out;
369 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
370 if (!(CPU_IS_060 || CPU_IS_COLDFIRE))
371 context_size = fpstate[1];
372 /* Verify the frame format. */
373 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) &&
374 (fpstate[0] != fpu_version))
375 goto out;
376 if (CPU_IS_020_OR_030) {
377 if (m68k_fputype & FPU_68881 &&
378 !(context_size == 0x18 || context_size == 0xb4))
379 goto out;
380 if (m68k_fputype & FPU_68882 &&
381 !(context_size == 0x38 || context_size == 0xd4))
382 goto out;
383 } else if (CPU_IS_040) {
384 if (!(context_size == 0x00 ||
385 context_size == 0x28 ||
386 context_size == 0x60))
387 goto out;
388 } else if (CPU_IS_060) {
389 if (!(fpstate[3] == 0x00 ||
390 fpstate[3] == 0x60 ||
391 fpstate[3] == 0xe0))
392 goto out;
393 } else if (CPU_IS_COLDFIRE) {
394 if (!(fpstate[3] == 0x00 ||
395 fpstate[3] == 0x05 ||
396 fpstate[3] == 0xe5))
397 goto out;
398 } else
399 goto out;
400 if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs,
401 sizeof(fpregs)))
402 goto out;
403
404 if (CPU_IS_COLDFIRE) {
405 __asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t"
406 "fmovel %1,%%fpcr\n\t"
407 "fmovel %2,%%fpsr\n\t"
408 "fmovel %3,%%fpiar"
409 : /* no outputs */
410 : "m" (fpregs.f_fpregs[0]),
411 "m" (fpregs.f_fpcntl[0]),
412 "m" (fpregs.f_fpcntl[1]),
413 "m" (fpregs.f_fpcntl[2]));
414 } else {
415 __asm__ volatile (".chip 68k/68881\n\t"
416 "fmovemx %0,%%fp0-%%fp7\n\t"
417 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
418 ".chip 68k"
419 : /* no outputs */
420 : "m" (*fpregs.f_fpregs),
421 "m" (*fpregs.f_fpcntl));
422 }
423 }
424 if (context_size &&
425 __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1,
426 context_size))
427 goto out;
428
429 if (CPU_IS_COLDFIRE) {
430 __asm__ volatile ("frestore %0" : : "m" (*fpstate));
431 } else {
432 __asm__ volatile (".chip 68k/68881\n\t"
433 "frestore %0\n\t"
434 ".chip 68k"
435 : : "m" (*fpstate));
436 }
437 err = 0;
438
439 out:
440 return err;
441 }
442
443 /*
444 * Set up a signal frame.
445 */
save_fpu_state(struct sigcontext * sc,struct pt_regs * regs)446 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
447 {
448 if (FPU_IS_EMU) {
449 /* save registers */
450 memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12);
451 memcpy(sc->sc_fpregs, current->thread.fp, 24);
452 return;
453 }
454
455 if (CPU_IS_COLDFIRE) {
456 __asm__ volatile ("fsave %0"
457 : : "m" (*sc->sc_fpstate) : "memory");
458 } else {
459 __asm__ volatile (".chip 68k/68881\n\t"
460 "fsave %0\n\t"
461 ".chip 68k"
462 : : "m" (*sc->sc_fpstate) : "memory");
463 }
464
465 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
466 fpu_version = sc->sc_fpstate[0];
467 if (CPU_IS_020_OR_030 &&
468 regs->vector >= (VEC_FPBRUC * 4) &&
469 regs->vector <= (VEC_FPNAN * 4)) {
470 /* Clear pending exception in 68882 idle frame */
471 if (*(unsigned short *) sc->sc_fpstate == 0x1f38)
472 sc->sc_fpstate[0x38] |= 1 << 3;
473 }
474
475 if (CPU_IS_COLDFIRE) {
476 __asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t"
477 "fmovel %%fpcr,%1\n\t"
478 "fmovel %%fpsr,%2\n\t"
479 "fmovel %%fpiar,%3"
480 : "=m" (sc->sc_fpregs[0]),
481 "=m" (sc->sc_fpcntl[0]),
482 "=m" (sc->sc_fpcntl[1]),
483 "=m" (sc->sc_fpcntl[2])
484 : /* no inputs */
485 : "memory");
486 } else {
487 __asm__ volatile (".chip 68k/68881\n\t"
488 "fmovemx %%fp0-%%fp1,%0\n\t"
489 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
490 ".chip 68k"
491 : "=m" (*sc->sc_fpregs),
492 "=m" (*sc->sc_fpcntl)
493 : /* no inputs */
494 : "memory");
495 }
496 }
497 }
498
rt_save_fpu_state(struct ucontext __user * uc,struct pt_regs * regs)499 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
500 {
501 unsigned char fpstate[FPCONTEXT_SIZE];
502 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0);
503 int err = 0;
504
505 if (FPU_IS_EMU) {
506 /* save fpu control register */
507 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl,
508 current->thread.fpcntl, 12);
509 /* save all other fpu register */
510 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs,
511 current->thread.fp, 96);
512 return err;
513 }
514
515 if (CPU_IS_COLDFIRE) {
516 __asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory");
517 } else {
518 __asm__ volatile (".chip 68k/68881\n\t"
519 "fsave %0\n\t"
520 ".chip 68k"
521 : : "m" (*fpstate) : "memory");
522 }
523
524 err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate);
525 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
526 fpregset_t fpregs;
527 if (!(CPU_IS_060 || CPU_IS_COLDFIRE))
528 context_size = fpstate[1];
529 fpu_version = fpstate[0];
530 if (CPU_IS_020_OR_030 &&
531 regs->vector >= (VEC_FPBRUC * 4) &&
532 regs->vector <= (VEC_FPNAN * 4)) {
533 /* Clear pending exception in 68882 idle frame */
534 if (*(unsigned short *) fpstate == 0x1f38)
535 fpstate[0x38] |= 1 << 3;
536 }
537 if (CPU_IS_COLDFIRE) {
538 __asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t"
539 "fmovel %%fpcr,%1\n\t"
540 "fmovel %%fpsr,%2\n\t"
541 "fmovel %%fpiar,%3"
542 : "=m" (fpregs.f_fpregs[0]),
543 "=m" (fpregs.f_fpcntl[0]),
544 "=m" (fpregs.f_fpcntl[1]),
545 "=m" (fpregs.f_fpcntl[2])
546 : /* no inputs */
547 : "memory");
548 } else {
549 __asm__ volatile (".chip 68k/68881\n\t"
550 "fmovemx %%fp0-%%fp7,%0\n\t"
551 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
552 ".chip 68k"
553 : "=m" (*fpregs.f_fpregs),
554 "=m" (*fpregs.f_fpcntl)
555 : /* no inputs */
556 : "memory");
557 }
558 err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs,
559 sizeof(fpregs));
560 }
561 if (context_size)
562 err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4,
563 context_size);
564 return err;
565 }
566
567 #else /* CONFIG_FPU */
568
569 /*
570 * For the case with no FPU configured these all do nothing.
571 */
restore_fpu_state(struct sigcontext * sc)572 static inline int restore_fpu_state(struct sigcontext *sc)
573 {
574 return 0;
575 }
576
rt_restore_fpu_state(struct ucontext __user * uc)577 static inline int rt_restore_fpu_state(struct ucontext __user *uc)
578 {
579 return 0;
580 }
581
save_fpu_state(struct sigcontext * sc,struct pt_regs * regs)582 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
583 {
584 }
585
rt_save_fpu_state(struct ucontext __user * uc,struct pt_regs * regs)586 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
587 {
588 return 0;
589 }
590
591 #endif /* CONFIG_FPU */
592
mangle_kernel_stack(struct pt_regs * regs,int formatvec,void __user * fp)593 static int mangle_kernel_stack(struct pt_regs *regs, int formatvec,
594 void __user *fp)
595 {
596 int fsize = frame_extra_sizes(formatvec >> 12);
597 if (fsize < 0) {
598 /*
599 * user process trying to return with weird frame format
600 */
601 #ifdef DEBUG
602 printk("user process returning with weird frame format\n");
603 #endif
604 return 1;
605 }
606 if (!fsize) {
607 regs->format = formatvec >> 12;
608 regs->vector = formatvec & 0xfff;
609 } else {
610 struct switch_stack *sw = (struct switch_stack *)regs - 1;
611 unsigned long buf[fsize / 2]; /* yes, twice as much */
612
613 /* that'll make sure that expansion won't crap over data */
614 if (copy_from_user(buf + fsize / 4, fp, fsize))
615 return 1;
616
617 /* point of no return */
618 regs->format = formatvec >> 12;
619 regs->vector = formatvec & 0xfff;
620 #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack))
621 __asm__ __volatile__ (
622 #ifdef CONFIG_COLDFIRE
623 " movel %0,%/sp\n\t"
624 " bra ret_from_signal\n"
625 #else
626 " movel %0,%/a0\n\t"
627 " subl %1,%/a0\n\t" /* make room on stack */
628 " movel %/a0,%/sp\n\t" /* set stack pointer */
629 /* move switch_stack and pt_regs */
630 "1: movel %0@+,%/a0@+\n\t"
631 " dbra %2,1b\n\t"
632 " lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */
633 " lsrl #2,%1\n\t"
634 " subql #1,%1\n\t"
635 /* copy to the gap we'd made */
636 "2: movel %4@+,%/a0@+\n\t"
637 " dbra %1,2b\n\t"
638 " bral ret_from_signal\n"
639 #endif
640 : /* no outputs, it doesn't ever return */
641 : "a" (sw), "d" (fsize), "d" (frame_offset/4-1),
642 "n" (frame_offset), "a" (buf + fsize/4)
643 : "a0");
644 #undef frame_offset
645 }
646 return 0;
647 }
648
649 static inline int
restore_sigcontext(struct pt_regs * regs,struct sigcontext __user * usc,void __user * fp)650 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp)
651 {
652 int formatvec;
653 struct sigcontext context;
654 int err = 0;
655
656 /* Always make any pending restarted system calls return -EINTR */
657 current->restart_block.fn = do_no_restart_syscall;
658
659 /* get previous context */
660 if (copy_from_user(&context, usc, sizeof(context)))
661 goto badframe;
662
663 /* restore passed registers */
664 regs->d0 = context.sc_d0;
665 regs->d1 = context.sc_d1;
666 regs->a0 = context.sc_a0;
667 regs->a1 = context.sc_a1;
668 regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff);
669 regs->pc = context.sc_pc;
670 regs->orig_d0 = -1; /* disable syscall checks */
671 wrusp(context.sc_usp);
672 formatvec = context.sc_formatvec;
673
674 err = restore_fpu_state(&context);
675
676 if (err || mangle_kernel_stack(regs, formatvec, fp))
677 goto badframe;
678
679 return 0;
680
681 badframe:
682 return 1;
683 }
684
685 static inline int
rt_restore_ucontext(struct pt_regs * regs,struct switch_stack * sw,struct ucontext __user * uc)686 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
687 struct ucontext __user *uc)
688 {
689 int temp;
690 greg_t __user *gregs = uc->uc_mcontext.gregs;
691 unsigned long usp;
692 int err;
693
694 /* Always make any pending restarted system calls return -EINTR */
695 current->restart_block.fn = do_no_restart_syscall;
696
697 err = __get_user(temp, &uc->uc_mcontext.version);
698 if (temp != MCONTEXT_VERSION)
699 goto badframe;
700 /* restore passed registers */
701 err |= __get_user(regs->d0, &gregs[0]);
702 err |= __get_user(regs->d1, &gregs[1]);
703 err |= __get_user(regs->d2, &gregs[2]);
704 err |= __get_user(regs->d3, &gregs[3]);
705 err |= __get_user(regs->d4, &gregs[4]);
706 err |= __get_user(regs->d5, &gregs[5]);
707 err |= __get_user(sw->d6, &gregs[6]);
708 err |= __get_user(sw->d7, &gregs[7]);
709 err |= __get_user(regs->a0, &gregs[8]);
710 err |= __get_user(regs->a1, &gregs[9]);
711 err |= __get_user(regs->a2, &gregs[10]);
712 err |= __get_user(sw->a3, &gregs[11]);
713 err |= __get_user(sw->a4, &gregs[12]);
714 err |= __get_user(sw->a5, &gregs[13]);
715 err |= __get_user(sw->a6, &gregs[14]);
716 err |= __get_user(usp, &gregs[15]);
717 wrusp(usp);
718 err |= __get_user(regs->pc, &gregs[16]);
719 err |= __get_user(temp, &gregs[17]);
720 regs->sr = (regs->sr & 0xff00) | (temp & 0xff);
721 regs->orig_d0 = -1; /* disable syscall checks */
722 err |= __get_user(temp, &uc->uc_formatvec);
723
724 err |= rt_restore_fpu_state(uc);
725 err |= restore_altstack(&uc->uc_stack);
726
727 if (err)
728 goto badframe;
729
730 if (mangle_kernel_stack(regs, temp, &uc->uc_extra))
731 goto badframe;
732
733 return 0;
734
735 badframe:
736 return 1;
737 }
738
do_sigreturn(struct pt_regs * regs,struct switch_stack * sw)739 asmlinkage int do_sigreturn(struct pt_regs *regs, struct switch_stack *sw)
740 {
741 unsigned long usp = rdusp();
742 struct sigframe __user *frame = (struct sigframe __user *)(usp - 4);
743 sigset_t set;
744
745 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
746 goto badframe;
747 if (__get_user(set.sig[0], &frame->sc.sc_mask) ||
748 (_NSIG_WORDS > 1 &&
749 __copy_from_user(&set.sig[1], &frame->extramask,
750 sizeof(frame->extramask))))
751 goto badframe;
752
753 set_current_blocked(&set);
754
755 if (restore_sigcontext(regs, &frame->sc, frame + 1))
756 goto badframe;
757 return regs->d0;
758
759 badframe:
760 force_sig(SIGSEGV, current);
761 return 0;
762 }
763
do_rt_sigreturn(struct pt_regs * regs,struct switch_stack * sw)764 asmlinkage int do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw)
765 {
766 unsigned long usp = rdusp();
767 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4);
768 sigset_t set;
769
770 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
771 goto badframe;
772 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
773 goto badframe;
774
775 set_current_blocked(&set);
776
777 if (rt_restore_ucontext(regs, sw, &frame->uc))
778 goto badframe;
779 return regs->d0;
780
781 badframe:
782 force_sig(SIGSEGV, current);
783 return 0;
784 }
785
setup_sigcontext(struct sigcontext * sc,struct pt_regs * regs,unsigned long mask)786 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
787 unsigned long mask)
788 {
789 sc->sc_mask = mask;
790 sc->sc_usp = rdusp();
791 sc->sc_d0 = regs->d0;
792 sc->sc_d1 = regs->d1;
793 sc->sc_a0 = regs->a0;
794 sc->sc_a1 = regs->a1;
795 sc->sc_sr = regs->sr;
796 sc->sc_pc = regs->pc;
797 sc->sc_formatvec = regs->format << 12 | regs->vector;
798 save_a5_state(sc, regs);
799 save_fpu_state(sc, regs);
800 }
801
rt_setup_ucontext(struct ucontext __user * uc,struct pt_regs * regs)802 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs)
803 {
804 struct switch_stack *sw = (struct switch_stack *)regs - 1;
805 greg_t __user *gregs = uc->uc_mcontext.gregs;
806 int err = 0;
807
808 err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
809 err |= __put_user(regs->d0, &gregs[0]);
810 err |= __put_user(regs->d1, &gregs[1]);
811 err |= __put_user(regs->d2, &gregs[2]);
812 err |= __put_user(regs->d3, &gregs[3]);
813 err |= __put_user(regs->d4, &gregs[4]);
814 err |= __put_user(regs->d5, &gregs[5]);
815 err |= __put_user(sw->d6, &gregs[6]);
816 err |= __put_user(sw->d7, &gregs[7]);
817 err |= __put_user(regs->a0, &gregs[8]);
818 err |= __put_user(regs->a1, &gregs[9]);
819 err |= __put_user(regs->a2, &gregs[10]);
820 err |= __put_user(sw->a3, &gregs[11]);
821 err |= __put_user(sw->a4, &gregs[12]);
822 err |= __put_user(sw->a5, &gregs[13]);
823 err |= __put_user(sw->a6, &gregs[14]);
824 err |= __put_user(rdusp(), &gregs[15]);
825 err |= __put_user(regs->pc, &gregs[16]);
826 err |= __put_user(regs->sr, &gregs[17]);
827 err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec);
828 err |= rt_save_fpu_state(uc, regs);
829 return err;
830 }
831
832 static inline void __user *
get_sigframe(struct ksignal * ksig,size_t frame_size)833 get_sigframe(struct ksignal *ksig, size_t frame_size)
834 {
835 unsigned long usp = sigsp(rdusp(), ksig);
836
837 return (void __user *)((usp - frame_size) & -8UL);
838 }
839
setup_frame(struct ksignal * ksig,sigset_t * set,struct pt_regs * regs)840 static int setup_frame(struct ksignal *ksig, sigset_t *set,
841 struct pt_regs *regs)
842 {
843 struct sigframe __user *frame;
844 int fsize = frame_extra_sizes(regs->format);
845 struct sigcontext context;
846 int err = 0, sig = ksig->sig;
847
848 if (fsize < 0) {
849 #ifdef DEBUG
850 printk ("setup_frame: Unknown frame format %#x\n",
851 regs->format);
852 #endif
853 return -EFAULT;
854 }
855
856 frame = get_sigframe(ksig, sizeof(*frame) + fsize);
857
858 if (fsize)
859 err |= copy_to_user (frame + 1, regs + 1, fsize);
860
861 err |= __put_user(sig, &frame->sig);
862
863 err |= __put_user(regs->vector, &frame->code);
864 err |= __put_user(&frame->sc, &frame->psc);
865
866 if (_NSIG_WORDS > 1)
867 err |= copy_to_user(frame->extramask, &set->sig[1],
868 sizeof(frame->extramask));
869
870 setup_sigcontext(&context, regs, set->sig[0]);
871 err |= copy_to_user (&frame->sc, &context, sizeof(context));
872
873 /* Set up to return from userspace. */
874 #ifdef CONFIG_MMU
875 err |= __put_user(frame->retcode, &frame->pretcode);
876 /* moveq #,d0; trap #0 */
877 err |= __put_user(0x70004e40 + (__NR_sigreturn << 16),
878 (long __user *)(frame->retcode));
879 #else
880 err |= __put_user((void *) ret_from_user_signal, &frame->pretcode);
881 #endif
882
883 if (err)
884 return -EFAULT;
885
886 push_cache ((unsigned long) &frame->retcode);
887
888 /*
889 * Set up registers for signal handler. All the state we are about
890 * to destroy is successfully copied to sigframe.
891 */
892 wrusp ((unsigned long) frame);
893 regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
894 adjustformat(regs);
895
896 /*
897 * This is subtle; if we build more than one sigframe, all but the
898 * first one will see frame format 0 and have fsize == 0, so we won't
899 * screw stkadj.
900 */
901 if (fsize)
902 regs->stkadj = fsize;
903
904 /* Prepare to skip over the extra stuff in the exception frame. */
905 if (regs->stkadj) {
906 struct pt_regs *tregs =
907 (struct pt_regs *)((ulong)regs + regs->stkadj);
908 #ifdef DEBUG
909 printk("Performing stackadjust=%04x\n", regs->stkadj);
910 #endif
911 /* This must be copied with decreasing addresses to
912 handle overlaps. */
913 tregs->vector = 0;
914 tregs->format = 0;
915 tregs->pc = regs->pc;
916 tregs->sr = regs->sr;
917 }
918 return 0;
919 }
920
setup_rt_frame(struct ksignal * ksig,sigset_t * set,struct pt_regs * regs)921 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
922 struct pt_regs *regs)
923 {
924 struct rt_sigframe __user *frame;
925 int fsize = frame_extra_sizes(regs->format);
926 int err = 0, sig = ksig->sig;
927
928 if (fsize < 0) {
929 #ifdef DEBUG
930 printk ("setup_frame: Unknown frame format %#x\n",
931 regs->format);
932 #endif
933 return -EFAULT;
934 }
935
936 frame = get_sigframe(ksig, sizeof(*frame));
937
938 if (fsize)
939 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize);
940
941 err |= __put_user(sig, &frame->sig);
942 err |= __put_user(&frame->info, &frame->pinfo);
943 err |= __put_user(&frame->uc, &frame->puc);
944 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
945
946 /* Create the ucontext. */
947 err |= __put_user(0, &frame->uc.uc_flags);
948 err |= __put_user(NULL, &frame->uc.uc_link);
949 err |= __save_altstack(&frame->uc.uc_stack, rdusp());
950 err |= rt_setup_ucontext(&frame->uc, regs);
951 err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set));
952
953 /* Set up to return from userspace. */
954 #ifdef CONFIG_MMU
955 err |= __put_user(frame->retcode, &frame->pretcode);
956 #ifdef __mcoldfire__
957 /* movel #__NR_rt_sigreturn,d0; trap #0 */
958 err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0));
959 err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16),
960 (long __user *)(frame->retcode + 4));
961 #else
962 /* moveq #,d0; notb d0; trap #0 */
963 err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16),
964 (long __user *)(frame->retcode + 0));
965 err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4));
966 #endif
967 #else
968 err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode);
969 #endif /* CONFIG_MMU */
970
971 if (err)
972 return -EFAULT;
973
974 push_cache ((unsigned long) &frame->retcode);
975
976 /*
977 * Set up registers for signal handler. All the state we are about
978 * to destroy is successfully copied to sigframe.
979 */
980 wrusp ((unsigned long) frame);
981 regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
982 adjustformat(regs);
983
984 /*
985 * This is subtle; if we build more than one sigframe, all but the
986 * first one will see frame format 0 and have fsize == 0, so we won't
987 * screw stkadj.
988 */
989 if (fsize)
990 regs->stkadj = fsize;
991
992 /* Prepare to skip over the extra stuff in the exception frame. */
993 if (regs->stkadj) {
994 struct pt_regs *tregs =
995 (struct pt_regs *)((ulong)regs + regs->stkadj);
996 #ifdef DEBUG
997 printk("Performing stackadjust=%04x\n", regs->stkadj);
998 #endif
999 /* This must be copied with decreasing addresses to
1000 handle overlaps. */
1001 tregs->vector = 0;
1002 tregs->format = 0;
1003 tregs->pc = regs->pc;
1004 tregs->sr = regs->sr;
1005 }
1006 return 0;
1007 }
1008
1009 static inline void
handle_restart(struct pt_regs * regs,struct k_sigaction * ka,int has_handler)1010 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
1011 {
1012 switch (regs->d0) {
1013 case -ERESTARTNOHAND:
1014 if (!has_handler)
1015 goto do_restart;
1016 regs->d0 = -EINTR;
1017 break;
1018
1019 case -ERESTART_RESTARTBLOCK:
1020 if (!has_handler) {
1021 regs->d0 = __NR_restart_syscall;
1022 regs->pc -= 2;
1023 break;
1024 }
1025 regs->d0 = -EINTR;
1026 break;
1027
1028 case -ERESTARTSYS:
1029 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
1030 regs->d0 = -EINTR;
1031 break;
1032 }
1033 /* fallthrough */
1034 case -ERESTARTNOINTR:
1035 do_restart:
1036 regs->d0 = regs->orig_d0;
1037 regs->pc -= 2;
1038 break;
1039 }
1040 }
1041
1042 /*
1043 * OK, we're invoking a handler
1044 */
1045 static void
handle_signal(struct ksignal * ksig,struct pt_regs * regs)1046 handle_signal(struct ksignal *ksig, struct pt_regs *regs)
1047 {
1048 sigset_t *oldset = sigmask_to_save();
1049 int err;
1050 /* are we from a system call? */
1051 if (regs->orig_d0 >= 0)
1052 /* If so, check system call restarting.. */
1053 handle_restart(regs, &ksig->ka, 1);
1054
1055 /* set up the stack frame */
1056 if (ksig->ka.sa.sa_flags & SA_SIGINFO)
1057 err = setup_rt_frame(ksig, oldset, regs);
1058 else
1059 err = setup_frame(ksig, oldset, regs);
1060
1061 signal_setup_done(err, ksig, 0);
1062
1063 if (test_thread_flag(TIF_DELAYED_TRACE)) {
1064 regs->sr &= ~0x8000;
1065 send_sig(SIGTRAP, current, 1);
1066 }
1067 }
1068
1069 /*
1070 * Note that 'init' is a special process: it doesn't get signals it doesn't
1071 * want to handle. Thus you cannot kill init even with a SIGKILL even by
1072 * mistake.
1073 */
do_signal(struct pt_regs * regs)1074 static void do_signal(struct pt_regs *regs)
1075 {
1076 struct ksignal ksig;
1077
1078 current->thread.esp0 = (unsigned long) regs;
1079
1080 if (get_signal(&ksig)) {
1081 /* Whee! Actually deliver the signal. */
1082 handle_signal(&ksig, regs);
1083 return;
1084 }
1085
1086 /* Did we come from a system call? */
1087 if (regs->orig_d0 >= 0)
1088 /* Restart the system call - no handlers present */
1089 handle_restart(regs, NULL, 0);
1090
1091 /* If there's no signal to deliver, we just restore the saved mask. */
1092 restore_saved_sigmask();
1093 }
1094
do_notify_resume(struct pt_regs * regs)1095 void do_notify_resume(struct pt_regs *regs)
1096 {
1097 if (test_thread_flag(TIF_SIGPENDING))
1098 do_signal(regs);
1099
1100 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
1101 tracehook_notify_resume(regs);
1102 }
1103