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/module.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 ((struct switch_stack *)regs - 1)->a5 = current->mm->start_data;
217 /*
218 * set format byte to make stack appear modulo 4, which it will
219 * be when doing the rte
220 */
221 regs->format = 0x4;
222 }
223
save_a5_state(struct sigcontext * sc,struct pt_regs * regs)224 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs)
225 {
226 sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5;
227 }
228
push_cache(unsigned long vaddr)229 static inline void push_cache(unsigned long vaddr)
230 {
231 }
232
233 #endif /* CONFIG_MMU */
234
235 /*
236 * Do a signal return; undo the signal stack.
237 *
238 * Keep the return code on the stack quadword aligned!
239 * That makes the cache flush below easier.
240 */
241
242 struct sigframe
243 {
244 char __user *pretcode;
245 int sig;
246 int code;
247 struct sigcontext __user *psc;
248 char retcode[8];
249 unsigned long extramask[_NSIG_WORDS-1];
250 struct sigcontext sc;
251 };
252
253 struct rt_sigframe
254 {
255 char __user *pretcode;
256 int sig;
257 struct siginfo __user *pinfo;
258 void __user *puc;
259 char retcode[8];
260 struct siginfo info;
261 struct ucontext uc;
262 };
263
264 #define FPCONTEXT_SIZE 216
265 #define uc_fpstate uc_filler[0]
266 #define uc_formatvec uc_filler[FPCONTEXT_SIZE/4]
267 #define uc_extra uc_filler[FPCONTEXT_SIZE/4+1]
268
269 #ifdef CONFIG_FPU
270
271 static unsigned char fpu_version; /* version number of fpu, set by setup_frame */
272
restore_fpu_state(struct sigcontext * sc)273 static inline int restore_fpu_state(struct sigcontext *sc)
274 {
275 int err = 1;
276
277 if (FPU_IS_EMU) {
278 /* restore registers */
279 memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12);
280 memcpy(current->thread.fp, sc->sc_fpregs, 24);
281 return 0;
282 }
283
284 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
285 /* Verify the frame format. */
286 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) &&
287 (sc->sc_fpstate[0] != fpu_version))
288 goto out;
289 if (CPU_IS_020_OR_030) {
290 if (m68k_fputype & FPU_68881 &&
291 !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4))
292 goto out;
293 if (m68k_fputype & FPU_68882 &&
294 !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4))
295 goto out;
296 } else if (CPU_IS_040) {
297 if (!(sc->sc_fpstate[1] == 0x00 ||
298 sc->sc_fpstate[1] == 0x28 ||
299 sc->sc_fpstate[1] == 0x60))
300 goto out;
301 } else if (CPU_IS_060) {
302 if (!(sc->sc_fpstate[3] == 0x00 ||
303 sc->sc_fpstate[3] == 0x60 ||
304 sc->sc_fpstate[3] == 0xe0))
305 goto out;
306 } else if (CPU_IS_COLDFIRE) {
307 if (!(sc->sc_fpstate[0] == 0x00 ||
308 sc->sc_fpstate[0] == 0x05 ||
309 sc->sc_fpstate[0] == 0xe5))
310 goto out;
311 } else
312 goto out;
313
314 if (CPU_IS_COLDFIRE) {
315 __asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t"
316 "fmovel %1,%%fpcr\n\t"
317 "fmovel %2,%%fpsr\n\t"
318 "fmovel %3,%%fpiar"
319 : /* no outputs */
320 : "m" (sc->sc_fpregs[0]),
321 "m" (sc->sc_fpcntl[0]),
322 "m" (sc->sc_fpcntl[1]),
323 "m" (sc->sc_fpcntl[2]));
324 } else {
325 __asm__ volatile (".chip 68k/68881\n\t"
326 "fmovemx %0,%%fp0-%%fp1\n\t"
327 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
328 ".chip 68k"
329 : /* no outputs */
330 : "m" (*sc->sc_fpregs),
331 "m" (*sc->sc_fpcntl));
332 }
333 }
334
335 if (CPU_IS_COLDFIRE) {
336 __asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate));
337 } else {
338 __asm__ volatile (".chip 68k/68881\n\t"
339 "frestore %0\n\t"
340 ".chip 68k"
341 : : "m" (*sc->sc_fpstate));
342 }
343 err = 0;
344
345 out:
346 return err;
347 }
348
rt_restore_fpu_state(struct ucontext __user * uc)349 static inline int rt_restore_fpu_state(struct ucontext __user *uc)
350 {
351 unsigned char fpstate[FPCONTEXT_SIZE];
352 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0);
353 fpregset_t fpregs;
354 int err = 1;
355
356 if (FPU_IS_EMU) {
357 /* restore fpu control register */
358 if (__copy_from_user(current->thread.fpcntl,
359 uc->uc_mcontext.fpregs.f_fpcntl, 12))
360 goto out;
361 /* restore all other fpu register */
362 if (__copy_from_user(current->thread.fp,
363 uc->uc_mcontext.fpregs.f_fpregs, 96))
364 goto out;
365 return 0;
366 }
367
368 if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate))
369 goto out;
370 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
371 if (!(CPU_IS_060 || CPU_IS_COLDFIRE))
372 context_size = fpstate[1];
373 /* Verify the frame format. */
374 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) &&
375 (fpstate[0] != fpu_version))
376 goto out;
377 if (CPU_IS_020_OR_030) {
378 if (m68k_fputype & FPU_68881 &&
379 !(context_size == 0x18 || context_size == 0xb4))
380 goto out;
381 if (m68k_fputype & FPU_68882 &&
382 !(context_size == 0x38 || context_size == 0xd4))
383 goto out;
384 } else if (CPU_IS_040) {
385 if (!(context_size == 0x00 ||
386 context_size == 0x28 ||
387 context_size == 0x60))
388 goto out;
389 } else if (CPU_IS_060) {
390 if (!(fpstate[3] == 0x00 ||
391 fpstate[3] == 0x60 ||
392 fpstate[3] == 0xe0))
393 goto out;
394 } else if (CPU_IS_COLDFIRE) {
395 if (!(fpstate[3] == 0x00 ||
396 fpstate[3] == 0x05 ||
397 fpstate[3] == 0xe5))
398 goto out;
399 } else
400 goto out;
401 if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs,
402 sizeof(fpregs)))
403 goto out;
404
405 if (CPU_IS_COLDFIRE) {
406 __asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t"
407 "fmovel %1,%%fpcr\n\t"
408 "fmovel %2,%%fpsr\n\t"
409 "fmovel %3,%%fpiar"
410 : /* no outputs */
411 : "m" (fpregs.f_fpregs[0]),
412 "m" (fpregs.f_fpcntl[0]),
413 "m" (fpregs.f_fpcntl[1]),
414 "m" (fpregs.f_fpcntl[2]));
415 } else {
416 __asm__ volatile (".chip 68k/68881\n\t"
417 "fmovemx %0,%%fp0-%%fp7\n\t"
418 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
419 ".chip 68k"
420 : /* no outputs */
421 : "m" (*fpregs.f_fpregs),
422 "m" (*fpregs.f_fpcntl));
423 }
424 }
425 if (context_size &&
426 __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1,
427 context_size))
428 goto out;
429
430 if (CPU_IS_COLDFIRE) {
431 __asm__ volatile ("frestore %0" : : "m" (*fpstate));
432 } else {
433 __asm__ volatile (".chip 68k/68881\n\t"
434 "frestore %0\n\t"
435 ".chip 68k"
436 : : "m" (*fpstate));
437 }
438 err = 0;
439
440 out:
441 return err;
442 }
443
444 /*
445 * Set up a signal frame.
446 */
save_fpu_state(struct sigcontext * sc,struct pt_regs * regs)447 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
448 {
449 if (FPU_IS_EMU) {
450 /* save registers */
451 memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12);
452 memcpy(sc->sc_fpregs, current->thread.fp, 24);
453 return;
454 }
455
456 if (CPU_IS_COLDFIRE) {
457 __asm__ volatile ("fsave %0"
458 : : "m" (*sc->sc_fpstate) : "memory");
459 } else {
460 __asm__ volatile (".chip 68k/68881\n\t"
461 "fsave %0\n\t"
462 ".chip 68k"
463 : : "m" (*sc->sc_fpstate) : "memory");
464 }
465
466 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
467 fpu_version = sc->sc_fpstate[0];
468 if (CPU_IS_020_OR_030 &&
469 regs->vector >= (VEC_FPBRUC * 4) &&
470 regs->vector <= (VEC_FPNAN * 4)) {
471 /* Clear pending exception in 68882 idle frame */
472 if (*(unsigned short *) sc->sc_fpstate == 0x1f38)
473 sc->sc_fpstate[0x38] |= 1 << 3;
474 }
475
476 if (CPU_IS_COLDFIRE) {
477 __asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t"
478 "fmovel %%fpcr,%1\n\t"
479 "fmovel %%fpsr,%2\n\t"
480 "fmovel %%fpiar,%3"
481 : "=m" (sc->sc_fpregs[0]),
482 "=m" (sc->sc_fpcntl[0]),
483 "=m" (sc->sc_fpcntl[1]),
484 "=m" (sc->sc_fpcntl[2])
485 : /* no inputs */
486 : "memory");
487 } else {
488 __asm__ volatile (".chip 68k/68881\n\t"
489 "fmovemx %%fp0-%%fp1,%0\n\t"
490 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
491 ".chip 68k"
492 : "=m" (*sc->sc_fpregs),
493 "=m" (*sc->sc_fpcntl)
494 : /* no inputs */
495 : "memory");
496 }
497 }
498 }
499
rt_save_fpu_state(struct ucontext __user * uc,struct pt_regs * regs)500 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
501 {
502 unsigned char fpstate[FPCONTEXT_SIZE];
503 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0);
504 int err = 0;
505
506 if (FPU_IS_EMU) {
507 /* save fpu control register */
508 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl,
509 current->thread.fpcntl, 12);
510 /* save all other fpu register */
511 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs,
512 current->thread.fp, 96);
513 return err;
514 }
515
516 if (CPU_IS_COLDFIRE) {
517 __asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory");
518 } else {
519 __asm__ volatile (".chip 68k/68881\n\t"
520 "fsave %0\n\t"
521 ".chip 68k"
522 : : "m" (*fpstate) : "memory");
523 }
524
525 err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate);
526 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
527 fpregset_t fpregs;
528 if (!(CPU_IS_060 || CPU_IS_COLDFIRE))
529 context_size = fpstate[1];
530 fpu_version = fpstate[0];
531 if (CPU_IS_020_OR_030 &&
532 regs->vector >= (VEC_FPBRUC * 4) &&
533 regs->vector <= (VEC_FPNAN * 4)) {
534 /* Clear pending exception in 68882 idle frame */
535 if (*(unsigned short *) fpstate == 0x1f38)
536 fpstate[0x38] |= 1 << 3;
537 }
538 if (CPU_IS_COLDFIRE) {
539 __asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t"
540 "fmovel %%fpcr,%1\n\t"
541 "fmovel %%fpsr,%2\n\t"
542 "fmovel %%fpiar,%3"
543 : "=m" (fpregs.f_fpregs[0]),
544 "=m" (fpregs.f_fpcntl[0]),
545 "=m" (fpregs.f_fpcntl[1]),
546 "=m" (fpregs.f_fpcntl[2])
547 : /* no inputs */
548 : "memory");
549 } else {
550 __asm__ volatile (".chip 68k/68881\n\t"
551 "fmovemx %%fp0-%%fp7,%0\n\t"
552 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
553 ".chip 68k"
554 : "=m" (*fpregs.f_fpregs),
555 "=m" (*fpregs.f_fpcntl)
556 : /* no inputs */
557 : "memory");
558 }
559 err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs,
560 sizeof(fpregs));
561 }
562 if (context_size)
563 err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4,
564 context_size);
565 return err;
566 }
567
568 #else /* CONFIG_FPU */
569
570 /*
571 * For the case with no FPU configured these all do nothing.
572 */
restore_fpu_state(struct sigcontext * sc)573 static inline int restore_fpu_state(struct sigcontext *sc)
574 {
575 return 0;
576 }
577
rt_restore_fpu_state(struct ucontext __user * uc)578 static inline int rt_restore_fpu_state(struct ucontext __user *uc)
579 {
580 return 0;
581 }
582
save_fpu_state(struct sigcontext * sc,struct pt_regs * regs)583 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
584 {
585 }
586
rt_save_fpu_state(struct ucontext __user * uc,struct pt_regs * regs)587 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
588 {
589 return 0;
590 }
591
592 #endif /* CONFIG_FPU */
593
mangle_kernel_stack(struct pt_regs * regs,int formatvec,void __user * fp)594 static int mangle_kernel_stack(struct pt_regs *regs, int formatvec,
595 void __user *fp)
596 {
597 int fsize = frame_extra_sizes(formatvec >> 12);
598 if (fsize < 0) {
599 /*
600 * user process trying to return with weird frame format
601 */
602 #ifdef DEBUG
603 printk("user process returning with weird frame format\n");
604 #endif
605 return 1;
606 }
607 if (!fsize) {
608 regs->format = formatvec >> 12;
609 regs->vector = formatvec & 0xfff;
610 } else {
611 struct switch_stack *sw = (struct switch_stack *)regs - 1;
612 unsigned long buf[fsize / 2]; /* yes, twice as much */
613
614 /* that'll make sure that expansion won't crap over data */
615 if (copy_from_user(buf + fsize / 4, fp, fsize))
616 return 1;
617
618 /* point of no return */
619 regs->format = formatvec >> 12;
620 regs->vector = formatvec & 0xfff;
621 #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack))
622 __asm__ __volatile__ (
623 #ifdef CONFIG_COLDFIRE
624 " movel %0,%/sp\n\t"
625 " bra ret_from_signal\n"
626 #else
627 " movel %0,%/a0\n\t"
628 " subl %1,%/a0\n\t" /* make room on stack */
629 " movel %/a0,%/sp\n\t" /* set stack pointer */
630 /* move switch_stack and pt_regs */
631 "1: movel %0@+,%/a0@+\n\t"
632 " dbra %2,1b\n\t"
633 " lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */
634 " lsrl #2,%1\n\t"
635 " subql #1,%1\n\t"
636 /* copy to the gap we'd made */
637 "2: movel %4@+,%/a0@+\n\t"
638 " dbra %1,2b\n\t"
639 " bral ret_from_signal\n"
640 #endif
641 : /* no outputs, it doesn't ever return */
642 : "a" (sw), "d" (fsize), "d" (frame_offset/4-1),
643 "n" (frame_offset), "a" (buf + fsize/4)
644 : "a0");
645 #undef frame_offset
646 }
647 return 0;
648 }
649
650 static inline int
restore_sigcontext(struct pt_regs * regs,struct sigcontext __user * usc,void __user * fp)651 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp)
652 {
653 int formatvec;
654 struct sigcontext context;
655 int err = 0;
656
657 /* Always make any pending restarted system calls return -EINTR */
658 current->restart_block.fn = do_no_restart_syscall;
659
660 /* get previous context */
661 if (copy_from_user(&context, usc, sizeof(context)))
662 goto badframe;
663
664 /* restore passed registers */
665 regs->d0 = context.sc_d0;
666 regs->d1 = context.sc_d1;
667 regs->a0 = context.sc_a0;
668 regs->a1 = context.sc_a1;
669 regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff);
670 regs->pc = context.sc_pc;
671 regs->orig_d0 = -1; /* disable syscall checks */
672 wrusp(context.sc_usp);
673 formatvec = context.sc_formatvec;
674
675 err = restore_fpu_state(&context);
676
677 if (err || mangle_kernel_stack(regs, formatvec, fp))
678 goto badframe;
679
680 return 0;
681
682 badframe:
683 return 1;
684 }
685
686 static inline int
rt_restore_ucontext(struct pt_regs * regs,struct switch_stack * sw,struct ucontext __user * uc)687 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
688 struct ucontext __user *uc)
689 {
690 int temp;
691 greg_t __user *gregs = uc->uc_mcontext.gregs;
692 unsigned long usp;
693 int err;
694
695 /* Always make any pending restarted system calls return -EINTR */
696 current->restart_block.fn = do_no_restart_syscall;
697
698 err = __get_user(temp, &uc->uc_mcontext.version);
699 if (temp != MCONTEXT_VERSION)
700 goto badframe;
701 /* restore passed registers */
702 err |= __get_user(regs->d0, &gregs[0]);
703 err |= __get_user(regs->d1, &gregs[1]);
704 err |= __get_user(regs->d2, &gregs[2]);
705 err |= __get_user(regs->d3, &gregs[3]);
706 err |= __get_user(regs->d4, &gregs[4]);
707 err |= __get_user(regs->d5, &gregs[5]);
708 err |= __get_user(sw->d6, &gregs[6]);
709 err |= __get_user(sw->d7, &gregs[7]);
710 err |= __get_user(regs->a0, &gregs[8]);
711 err |= __get_user(regs->a1, &gregs[9]);
712 err |= __get_user(regs->a2, &gregs[10]);
713 err |= __get_user(sw->a3, &gregs[11]);
714 err |= __get_user(sw->a4, &gregs[12]);
715 err |= __get_user(sw->a5, &gregs[13]);
716 err |= __get_user(sw->a6, &gregs[14]);
717 err |= __get_user(usp, &gregs[15]);
718 wrusp(usp);
719 err |= __get_user(regs->pc, &gregs[16]);
720 err |= __get_user(temp, &gregs[17]);
721 regs->sr = (regs->sr & 0xff00) | (temp & 0xff);
722 regs->orig_d0 = -1; /* disable syscall checks */
723 err |= __get_user(temp, &uc->uc_formatvec);
724
725 err |= rt_restore_fpu_state(uc);
726 err |= restore_altstack(&uc->uc_stack);
727
728 if (err)
729 goto badframe;
730
731 if (mangle_kernel_stack(regs, temp, &uc->uc_extra))
732 goto badframe;
733
734 return 0;
735
736 badframe:
737 return 1;
738 }
739
do_sigreturn(unsigned long __unused)740 asmlinkage int do_sigreturn(unsigned long __unused)
741 {
742 struct switch_stack *sw = (struct switch_stack *) &__unused;
743 struct pt_regs *regs = (struct pt_regs *) (sw + 1);
744 unsigned long usp = rdusp();
745 struct sigframe __user *frame = (struct sigframe __user *)(usp - 4);
746 sigset_t set;
747
748 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
749 goto badframe;
750 if (__get_user(set.sig[0], &frame->sc.sc_mask) ||
751 (_NSIG_WORDS > 1 &&
752 __copy_from_user(&set.sig[1], &frame->extramask,
753 sizeof(frame->extramask))))
754 goto badframe;
755
756 set_current_blocked(&set);
757
758 if (restore_sigcontext(regs, &frame->sc, frame + 1))
759 goto badframe;
760 return regs->d0;
761
762 badframe:
763 force_sig(SIGSEGV, current);
764 return 0;
765 }
766
do_rt_sigreturn(unsigned long __unused)767 asmlinkage int do_rt_sigreturn(unsigned long __unused)
768 {
769 struct switch_stack *sw = (struct switch_stack *) &__unused;
770 struct pt_regs *regs = (struct pt_regs *) (sw + 1);
771 unsigned long usp = rdusp();
772 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4);
773 sigset_t set;
774
775 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
776 goto badframe;
777 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
778 goto badframe;
779
780 set_current_blocked(&set);
781
782 if (rt_restore_ucontext(regs, sw, &frame->uc))
783 goto badframe;
784 return regs->d0;
785
786 badframe:
787 force_sig(SIGSEGV, current);
788 return 0;
789 }
790
setup_sigcontext(struct sigcontext * sc,struct pt_regs * regs,unsigned long mask)791 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
792 unsigned long mask)
793 {
794 sc->sc_mask = mask;
795 sc->sc_usp = rdusp();
796 sc->sc_d0 = regs->d0;
797 sc->sc_d1 = regs->d1;
798 sc->sc_a0 = regs->a0;
799 sc->sc_a1 = regs->a1;
800 sc->sc_sr = regs->sr;
801 sc->sc_pc = regs->pc;
802 sc->sc_formatvec = regs->format << 12 | regs->vector;
803 save_a5_state(sc, regs);
804 save_fpu_state(sc, regs);
805 }
806
rt_setup_ucontext(struct ucontext __user * uc,struct pt_regs * regs)807 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs)
808 {
809 struct switch_stack *sw = (struct switch_stack *)regs - 1;
810 greg_t __user *gregs = uc->uc_mcontext.gregs;
811 int err = 0;
812
813 err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
814 err |= __put_user(regs->d0, &gregs[0]);
815 err |= __put_user(regs->d1, &gregs[1]);
816 err |= __put_user(regs->d2, &gregs[2]);
817 err |= __put_user(regs->d3, &gregs[3]);
818 err |= __put_user(regs->d4, &gregs[4]);
819 err |= __put_user(regs->d5, &gregs[5]);
820 err |= __put_user(sw->d6, &gregs[6]);
821 err |= __put_user(sw->d7, &gregs[7]);
822 err |= __put_user(regs->a0, &gregs[8]);
823 err |= __put_user(regs->a1, &gregs[9]);
824 err |= __put_user(regs->a2, &gregs[10]);
825 err |= __put_user(sw->a3, &gregs[11]);
826 err |= __put_user(sw->a4, &gregs[12]);
827 err |= __put_user(sw->a5, &gregs[13]);
828 err |= __put_user(sw->a6, &gregs[14]);
829 err |= __put_user(rdusp(), &gregs[15]);
830 err |= __put_user(regs->pc, &gregs[16]);
831 err |= __put_user(regs->sr, &gregs[17]);
832 err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec);
833 err |= rt_save_fpu_state(uc, regs);
834 return err;
835 }
836
837 static inline void __user *
get_sigframe(struct ksignal * ksig,size_t frame_size)838 get_sigframe(struct ksignal *ksig, size_t frame_size)
839 {
840 unsigned long usp = sigsp(rdusp(), ksig);
841
842 return (void __user *)((usp - frame_size) & -8UL);
843 }
844
setup_frame(struct ksignal * ksig,sigset_t * set,struct pt_regs * regs)845 static int setup_frame(struct ksignal *ksig, sigset_t *set,
846 struct pt_regs *regs)
847 {
848 struct sigframe __user *frame;
849 int fsize = frame_extra_sizes(regs->format);
850 struct sigcontext context;
851 int err = 0, sig = ksig->sig;
852
853 if (fsize < 0) {
854 #ifdef DEBUG
855 printk ("setup_frame: Unknown frame format %#x\n",
856 regs->format);
857 #endif
858 return -EFAULT;
859 }
860
861 frame = get_sigframe(ksig, sizeof(*frame) + fsize);
862
863 if (fsize)
864 err |= copy_to_user (frame + 1, regs + 1, fsize);
865
866 err |= __put_user(sig, &frame->sig);
867
868 err |= __put_user(regs->vector, &frame->code);
869 err |= __put_user(&frame->sc, &frame->psc);
870
871 if (_NSIG_WORDS > 1)
872 err |= copy_to_user(frame->extramask, &set->sig[1],
873 sizeof(frame->extramask));
874
875 setup_sigcontext(&context, regs, set->sig[0]);
876 err |= copy_to_user (&frame->sc, &context, sizeof(context));
877
878 /* Set up to return from userspace. */
879 #ifdef CONFIG_MMU
880 err |= __put_user(frame->retcode, &frame->pretcode);
881 /* moveq #,d0; trap #0 */
882 err |= __put_user(0x70004e40 + (__NR_sigreturn << 16),
883 (long __user *)(frame->retcode));
884 #else
885 err |= __put_user((void *) ret_from_user_signal, &frame->pretcode);
886 #endif
887
888 if (err)
889 return -EFAULT;
890
891 push_cache ((unsigned long) &frame->retcode);
892
893 /*
894 * Set up registers for signal handler. All the state we are about
895 * to destroy is successfully copied to sigframe.
896 */
897 wrusp ((unsigned long) frame);
898 regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
899 adjustformat(regs);
900
901 /*
902 * This is subtle; if we build more than one sigframe, all but the
903 * first one will see frame format 0 and have fsize == 0, so we won't
904 * screw stkadj.
905 */
906 if (fsize)
907 regs->stkadj = fsize;
908
909 /* Prepare to skip over the extra stuff in the exception frame. */
910 if (regs->stkadj) {
911 struct pt_regs *tregs =
912 (struct pt_regs *)((ulong)regs + regs->stkadj);
913 #ifdef DEBUG
914 printk("Performing stackadjust=%04x\n", regs->stkadj);
915 #endif
916 /* This must be copied with decreasing addresses to
917 handle overlaps. */
918 tregs->vector = 0;
919 tregs->format = 0;
920 tregs->pc = regs->pc;
921 tregs->sr = regs->sr;
922 }
923 return 0;
924 }
925
setup_rt_frame(struct ksignal * ksig,sigset_t * set,struct pt_regs * regs)926 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
927 struct pt_regs *regs)
928 {
929 struct rt_sigframe __user *frame;
930 int fsize = frame_extra_sizes(regs->format);
931 int err = 0, sig = ksig->sig;
932
933 if (fsize < 0) {
934 #ifdef DEBUG
935 printk ("setup_frame: Unknown frame format %#x\n",
936 regs->format);
937 #endif
938 return -EFAULT;
939 }
940
941 frame = get_sigframe(ksig, sizeof(*frame));
942
943 if (fsize)
944 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize);
945
946 err |= __put_user(sig, &frame->sig);
947 err |= __put_user(&frame->info, &frame->pinfo);
948 err |= __put_user(&frame->uc, &frame->puc);
949 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
950
951 /* Create the ucontext. */
952 err |= __put_user(0, &frame->uc.uc_flags);
953 err |= __put_user(NULL, &frame->uc.uc_link);
954 err |= __save_altstack(&frame->uc.uc_stack, rdusp());
955 err |= rt_setup_ucontext(&frame->uc, regs);
956 err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set));
957
958 /* Set up to return from userspace. */
959 #ifdef CONFIG_MMU
960 err |= __put_user(frame->retcode, &frame->pretcode);
961 #ifdef __mcoldfire__
962 /* movel #__NR_rt_sigreturn,d0; trap #0 */
963 err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0));
964 err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16),
965 (long __user *)(frame->retcode + 4));
966 #else
967 /* moveq #,d0; notb d0; trap #0 */
968 err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16),
969 (long __user *)(frame->retcode + 0));
970 err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4));
971 #endif
972 #else
973 err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode);
974 #endif /* CONFIG_MMU */
975
976 if (err)
977 return -EFAULT;
978
979 push_cache ((unsigned long) &frame->retcode);
980
981 /*
982 * Set up registers for signal handler. All the state we are about
983 * to destroy is successfully copied to sigframe.
984 */
985 wrusp ((unsigned long) frame);
986 regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
987 adjustformat(regs);
988
989 /*
990 * This is subtle; if we build more than one sigframe, all but the
991 * first one will see frame format 0 and have fsize == 0, so we won't
992 * screw stkadj.
993 */
994 if (fsize)
995 regs->stkadj = fsize;
996
997 /* Prepare to skip over the extra stuff in the exception frame. */
998 if (regs->stkadj) {
999 struct pt_regs *tregs =
1000 (struct pt_regs *)((ulong)regs + regs->stkadj);
1001 #ifdef DEBUG
1002 printk("Performing stackadjust=%04x\n", regs->stkadj);
1003 #endif
1004 /* This must be copied with decreasing addresses to
1005 handle overlaps. */
1006 tregs->vector = 0;
1007 tregs->format = 0;
1008 tregs->pc = regs->pc;
1009 tregs->sr = regs->sr;
1010 }
1011 return 0;
1012 }
1013
1014 static inline void
handle_restart(struct pt_regs * regs,struct k_sigaction * ka,int has_handler)1015 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
1016 {
1017 switch (regs->d0) {
1018 case -ERESTARTNOHAND:
1019 if (!has_handler)
1020 goto do_restart;
1021 regs->d0 = -EINTR;
1022 break;
1023
1024 case -ERESTART_RESTARTBLOCK:
1025 if (!has_handler) {
1026 regs->d0 = __NR_restart_syscall;
1027 regs->pc -= 2;
1028 break;
1029 }
1030 regs->d0 = -EINTR;
1031 break;
1032
1033 case -ERESTARTSYS:
1034 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
1035 regs->d0 = -EINTR;
1036 break;
1037 }
1038 /* fallthrough */
1039 case -ERESTARTNOINTR:
1040 do_restart:
1041 regs->d0 = regs->orig_d0;
1042 regs->pc -= 2;
1043 break;
1044 }
1045 }
1046
1047 /*
1048 * OK, we're invoking a handler
1049 */
1050 static void
handle_signal(struct ksignal * ksig,struct pt_regs * regs)1051 handle_signal(struct ksignal *ksig, struct pt_regs *regs)
1052 {
1053 sigset_t *oldset = sigmask_to_save();
1054 int err;
1055 /* are we from a system call? */
1056 if (regs->orig_d0 >= 0)
1057 /* If so, check system call restarting.. */
1058 handle_restart(regs, &ksig->ka, 1);
1059
1060 /* set up the stack frame */
1061 if (ksig->ka.sa.sa_flags & SA_SIGINFO)
1062 err = setup_rt_frame(ksig, oldset, regs);
1063 else
1064 err = setup_frame(ksig, oldset, regs);
1065
1066 signal_setup_done(err, ksig, 0);
1067
1068 if (test_thread_flag(TIF_DELAYED_TRACE)) {
1069 regs->sr &= ~0x8000;
1070 send_sig(SIGTRAP, current, 1);
1071 }
1072 }
1073
1074 /*
1075 * Note that 'init' is a special process: it doesn't get signals it doesn't
1076 * want to handle. Thus you cannot kill init even with a SIGKILL even by
1077 * mistake.
1078 */
do_signal(struct pt_regs * regs)1079 static void do_signal(struct pt_regs *regs)
1080 {
1081 struct ksignal ksig;
1082
1083 current->thread.esp0 = (unsigned long) regs;
1084
1085 if (get_signal(&ksig)) {
1086 /* Whee! Actually deliver the signal. */
1087 handle_signal(&ksig, regs);
1088 return;
1089 }
1090
1091 /* Did we come from a system call? */
1092 if (regs->orig_d0 >= 0)
1093 /* Restart the system call - no handlers present */
1094 handle_restart(regs, NULL, 0);
1095
1096 /* If there's no signal to deliver, we just restore the saved mask. */
1097 restore_saved_sigmask();
1098 }
1099
do_notify_resume(struct pt_regs * regs)1100 void do_notify_resume(struct pt_regs *regs)
1101 {
1102 if (test_thread_flag(TIF_SIGPENDING))
1103 do_signal(regs);
1104
1105 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
1106 tracehook_notify_resume(regs);
1107 }
1108