]>
Commit | Line | Data |
---|---|---|
51533b61 MS |
1 | /* |
2 | * Copyright (C) 2003, Axis Communications AB. | |
3 | */ | |
4 | ||
5 | #include <linux/sched.h> | |
6 | #include <linux/mm.h> | |
7 | #include <linux/kernel.h> | |
8 | #include <linux/signal.h> | |
9 | #include <linux/errno.h> | |
10 | #include <linux/wait.h> | |
11 | #include <linux/ptrace.h> | |
12 | #include <linux/unistd.h> | |
13 | #include <linux/stddef.h> | |
14 | #include <linux/syscalls.h> | |
15 | #include <linux/vmalloc.h> | |
16 | ||
17 | #include <asm/io.h> | |
18 | #include <asm/processor.h> | |
19 | #include <asm/ucontext.h> | |
20 | #include <asm/uaccess.h> | |
21 | #include <asm/arch/ptrace.h> | |
22 | #include <asm/arch/hwregs/cpu_vect.h> | |
23 | ||
24 | extern unsigned long cris_signal_return_page; | |
25 | ||
26 | /* Flag to check if a signal is blockable. */ | |
27 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
28 | ||
29 | /* | |
30 | * A syscall in CRIS is really a "break 13" instruction, which is 2 | |
31 | * bytes. The registers is manipulated so upon return the instruction | |
32 | * will be executed again. | |
33 | * | |
34 | * This relies on that PC points to the instruction after the break call. | |
35 | */ | |
36 | #define RESTART_CRIS_SYS(regs) regs->r10 = regs->orig_r10; regs->erp -= 2; | |
37 | ||
38 | /* Signal frames. */ | |
39 | struct signal_frame { | |
40 | struct sigcontext sc; | |
41 | unsigned long extramask[_NSIG_WORDS - 1]; | |
42 | unsigned char retcode[8]; /* Trampoline code. */ | |
43 | }; | |
44 | ||
45 | struct rt_signal_frame { | |
46 | struct siginfo *pinfo; | |
47 | void *puc; | |
48 | struct siginfo info; | |
49 | struct ucontext uc; | |
50 | unsigned char retcode[8]; /* Trampoline code. */ | |
51 | }; | |
52 | ||
53 | int do_signal(int restart, sigset_t *oldset, struct pt_regs *regs); | |
54 | void keep_debug_flags(unsigned long oldccs, unsigned long oldspc, | |
55 | struct pt_regs *regs); | |
56 | /* | |
57 | * Swap in the new signal mask, and wait for a signal. Define some | |
58 | * dummy arguments to be able to reach the regs argument. | |
59 | */ | |
60 | int | |
61 | sys_sigsuspend(old_sigset_t mask, long r11, long r12, long r13, long mof, | |
62 | long srp, struct pt_regs *regs) | |
63 | { | |
64 | sigset_t saveset; | |
65 | ||
66 | mask &= _BLOCKABLE; | |
67 | ||
68 | spin_lock_irq(¤t->sighand->siglock); | |
69 | ||
70 | saveset = current->blocked; | |
71 | ||
72 | siginitset(¤t->blocked, mask); | |
73 | ||
74 | recalc_sigpending(); | |
75 | spin_unlock_irq(¤t->sighand->siglock); | |
76 | ||
77 | regs->r10 = -EINTR; | |
78 | ||
79 | while (1) { | |
80 | current->state = TASK_INTERRUPTIBLE; | |
81 | schedule(); | |
82 | ||
83 | if (do_signal(0, &saveset, regs)) { | |
84 | /* | |
85 | * This point is reached twice: once to call | |
86 | * the signal handler, then again to return | |
87 | * from the sigsuspend system call. When | |
88 | * calling the signal handler, R10 hold the | |
89 | * signal number as set by do_signal(). The | |
90 | * sigsuspend call will always return with | |
91 | * the restored value above; -EINTR. | |
92 | */ | |
93 | return regs->r10; | |
94 | } | |
95 | } | |
96 | } | |
97 | ||
98 | /* Define some dummy arguments to be able to reach the regs argument. */ | |
99 | int | |
100 | sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, long r12, long r13, | |
101 | long mof, long srp, struct pt_regs *regs) | |
102 | { | |
103 | sigset_t saveset; | |
104 | sigset_t newset; | |
105 | ||
106 | if (sigsetsize != sizeof(sigset_t)) | |
107 | return -EINVAL; | |
108 | ||
109 | if (copy_from_user(&newset, unewset, sizeof(newset))) | |
110 | return -EFAULT; | |
111 | ||
112 | sigdelsetmask(&newset, ~_BLOCKABLE); | |
113 | spin_lock_irq(¤t->sighand->siglock); | |
114 | ||
115 | saveset = current->blocked; | |
116 | current->blocked = newset; | |
117 | ||
118 | recalc_sigpending(); | |
119 | spin_unlock_irq(¤t->sighand->siglock); | |
120 | ||
121 | regs->r10 = -EINTR; | |
122 | ||
123 | while (1) { | |
124 | current->state = TASK_INTERRUPTIBLE; | |
125 | schedule(); | |
126 | ||
127 | if (do_signal(0, &saveset, regs)) { | |
128 | /* See comment in function above. */ | |
129 | return regs->r10; | |
130 | } | |
131 | } | |
132 | } | |
133 | ||
134 | int | |
135 | sys_sigaction(int signal, const struct old_sigaction *act, | |
136 | struct old_sigaction *oact) | |
137 | { | |
138 | int retval; | |
139 | struct k_sigaction newk; | |
140 | struct k_sigaction oldk; | |
141 | ||
142 | if (act) { | |
143 | old_sigset_t mask; | |
144 | ||
145 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | |
146 | __get_user(newk.sa.sa_handler, &act->sa_handler) || | |
147 | __get_user(newk.sa.sa_restorer, &act->sa_restorer)) | |
148 | return -EFAULT; | |
149 | ||
150 | __get_user(newk.sa.sa_flags, &act->sa_flags); | |
151 | __get_user(mask, &act->sa_mask); | |
152 | siginitset(&newk.sa.sa_mask, mask); | |
153 | } | |
154 | ||
155 | retval = do_sigaction(signal, act ? &newk : NULL, oact ? &oldk : NULL); | |
156 | ||
157 | if (!retval && oact) { | |
158 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
159 | __put_user(oldk.sa.sa_handler, &oact->sa_handler) || | |
160 | __put_user(oldk.sa.sa_restorer, &oact->sa_restorer)) | |
161 | return -EFAULT; | |
162 | ||
163 | __put_user(oldk.sa.sa_flags, &oact->sa_flags); | |
164 | __put_user(oldk.sa.sa_mask.sig[0], &oact->sa_mask); | |
165 | } | |
166 | ||
167 | return retval; | |
168 | } | |
169 | ||
170 | int | |
171 | sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss) | |
172 | { | |
173 | return do_sigaltstack(uss, uoss, rdusp()); | |
174 | } | |
175 | ||
176 | static int | |
177 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) | |
178 | { | |
179 | unsigned int err = 0; | |
180 | unsigned long old_usp; | |
181 | ||
182 | /* Always make any pending restarted system calls return -EINTR */ | |
183 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
184 | ||
185 | /* | |
186 | * Restore the registers from &sc->regs. sc is already checked | |
187 | * for VERIFY_READ since the signal_frame was previously | |
188 | * checked in sys_sigreturn(). | |
189 | */ | |
190 | if (__copy_from_user(regs, sc, sizeof(struct pt_regs))) | |
191 | goto badframe; | |
192 | ||
193 | /* Make that the user-mode flag is set. */ | |
194 | regs->ccs |= (1 << (U_CCS_BITNR + CCS_SHIFT)); | |
195 | ||
196 | /* Restore the old USP. */ | |
197 | err |= __get_user(old_usp, &sc->usp); | |
198 | wrusp(old_usp); | |
199 | ||
200 | return err; | |
201 | ||
202 | badframe: | |
203 | return 1; | |
204 | } | |
205 | ||
206 | /* Define some dummy arguments to be able to reach the regs argument. */ | |
207 | asmlinkage int | |
208 | sys_sigreturn(long r10, long r11, long r12, long r13, long mof, long srp, | |
209 | struct pt_regs *regs) | |
210 | { | |
211 | sigset_t set; | |
212 | struct signal_frame __user *frame; | |
213 | unsigned long oldspc = regs->spc; | |
214 | unsigned long oldccs = regs->ccs; | |
215 | ||
216 | frame = (struct signal_frame *) rdusp(); | |
217 | ||
218 | /* | |
219 | * Since the signal is stacked on a dword boundary, the frame | |
220 | * should be dword aligned here as well. It it's not, then the | |
221 | * user is trying some funny business. | |
222 | */ | |
223 | if (((long)frame) & 3) | |
224 | goto badframe; | |
225 | ||
226 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
227 | goto badframe; | |
228 | ||
229 | if (__get_user(set.sig[0], &frame->sc.oldmask) || | |
230 | (_NSIG_WORDS > 1 && __copy_from_user(&set.sig[1], | |
231 | frame->extramask, | |
232 | sizeof(frame->extramask)))) | |
233 | goto badframe; | |
234 | ||
235 | sigdelsetmask(&set, ~_BLOCKABLE); | |
236 | spin_lock_irq(¤t->sighand->siglock); | |
237 | ||
238 | current->blocked = set; | |
239 | ||
240 | recalc_sigpending(); | |
241 | spin_unlock_irq(¤t->sighand->siglock); | |
242 | ||
243 | if (restore_sigcontext(regs, &frame->sc)) | |
244 | goto badframe; | |
245 | ||
246 | keep_debug_flags(oldccs, oldspc, regs); | |
247 | ||
248 | return regs->r10; | |
249 | ||
250 | badframe: | |
251 | force_sig(SIGSEGV, current); | |
252 | return 0; | |
253 | } | |
254 | ||
255 | /* Define some dummy variables to be able to reach the regs argument. */ | |
256 | asmlinkage int | |
257 | sys_rt_sigreturn(long r10, long r11, long r12, long r13, long mof, long srp, | |
258 | struct pt_regs *regs) | |
259 | { | |
260 | sigset_t set; | |
261 | struct rt_signal_frame __user *frame; | |
262 | unsigned long oldspc = regs->spc; | |
263 | unsigned long oldccs = regs->ccs; | |
264 | ||
265 | frame = (struct rt_signal_frame *) rdusp(); | |
266 | ||
267 | /* | |
268 | * Since the signal is stacked on a dword boundary, the frame | |
269 | * should be dword aligned here as well. It it's not, then the | |
270 | * user is trying some funny business. | |
271 | */ | |
272 | if (((long)frame) & 3) | |
273 | goto badframe; | |
274 | ||
275 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
276 | goto badframe; | |
277 | ||
278 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
279 | goto badframe; | |
280 | ||
281 | sigdelsetmask(&set, ~_BLOCKABLE); | |
282 | spin_lock_irq(¤t->sighand->siglock); | |
283 | ||
284 | current->blocked = set; | |
285 | ||
286 | recalc_sigpending(); | |
287 | spin_unlock_irq(¤t->sighand->siglock); | |
288 | ||
289 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) | |
290 | goto badframe; | |
291 | ||
292 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, rdusp()) == -EFAULT) | |
293 | goto badframe; | |
294 | ||
295 | keep_debug_flags(oldccs, oldspc, regs); | |
296 | ||
297 | return regs->r10; | |
298 | ||
299 | badframe: | |
300 | force_sig(SIGSEGV, current); | |
301 | return 0; | |
302 | } | |
303 | ||
304 | /* Setup a signal frame. */ | |
305 | static int | |
306 | setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, | |
307 | unsigned long mask) | |
308 | { | |
309 | int err; | |
310 | unsigned long usp; | |
311 | ||
312 | err = 0; | |
313 | usp = rdusp(); | |
314 | ||
315 | /* | |
316 | * Copy the registers. They are located first in sc, so it's | |
317 | * possible to use sc directly. | |
318 | */ | |
319 | err |= __copy_to_user(sc, regs, sizeof(struct pt_regs)); | |
320 | ||
321 | err |= __put_user(mask, &sc->oldmask); | |
322 | err |= __put_user(usp, &sc->usp); | |
323 | ||
324 | return err; | |
325 | } | |
326 | ||
327 | /* Figure out where to put the new signal frame - usually on the stack. */ | |
328 | static inline void __user * | |
329 | get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) | |
330 | { | |
331 | unsigned long sp; | |
332 | ||
333 | sp = rdusp(); | |
334 | ||
335 | /* This is the X/Open sanctioned signal stack switching. */ | |
336 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
337 | if (!on_sig_stack(sp)) | |
338 | sp = current->sas_ss_sp + current->sas_ss_size; | |
339 | } | |
340 | ||
341 | /* Make sure the frame is dword-aligned. */ | |
342 | sp &= ~3; | |
343 | ||
344 | return (void __user *)(sp - frame_size); | |
345 | } | |
346 | ||
347 | /* Grab and setup a signal frame. | |
348 | * | |
349 | * Basically a lot of state-info is stacked, and arranged for the | |
350 | * user-mode program to return to the kernel using either a trampiline | |
351 | * which performs the syscall sigreturn(), or a provided user-mode | |
352 | * trampoline. | |
353 | */ | |
354 | static void | |
355 | setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, | |
356 | struct pt_regs * regs) | |
357 | { | |
358 | int err; | |
359 | unsigned long return_ip; | |
360 | struct signal_frame __user *frame; | |
361 | ||
362 | err = 0; | |
363 | frame = get_sigframe(ka, regs, sizeof(*frame)); | |
364 | ||
365 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
366 | goto give_sigsegv; | |
367 | ||
368 | err |= setup_sigcontext(&frame->sc, regs, set->sig[0]); | |
369 | ||
370 | if (err) | |
371 | goto give_sigsegv; | |
372 | ||
373 | if (_NSIG_WORDS > 1) { | |
374 | err |= __copy_to_user(frame->extramask, &set->sig[1], | |
375 | sizeof(frame->extramask)); | |
376 | } | |
377 | ||
378 | if (err) | |
379 | goto give_sigsegv; | |
380 | ||
381 | /* | |
382 | * Set up to return from user-space. If provided, use a stub | |
383 | * already located in user-space. | |
384 | */ | |
385 | if (ka->sa.sa_flags & SA_RESTORER) { | |
386 | return_ip = (unsigned long)ka->sa.sa_restorer; | |
387 | } else { | |
388 | /* Trampoline - the desired return ip is in the signal return page. */ | |
389 | return_ip = cris_signal_return_page; | |
390 | ||
391 | /* | |
392 | * This is movu.w __NR_sigreturn, r9; break 13; | |
393 | * | |
394 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
395 | * reasons and because gdb uses it as a signature to notice | |
396 | * signal handler stack frames. | |
397 | */ | |
398 | err |= __put_user(0x9c5f, (short __user*)(frame->retcode+0)); | |
399 | err |= __put_user(__NR_sigreturn, (short __user*)(frame->retcode+2)); | |
400 | err |= __put_user(0xe93d, (short __user*)(frame->retcode+4)); | |
401 | } | |
402 | ||
403 | if (err) | |
404 | goto give_sigsegv; | |
405 | ||
406 | /* | |
407 | * Set up registers for signal handler. | |
408 | * | |
409 | * Where the code enters now. | |
410 | * Where the code enter later. | |
411 | * First argument, signo. | |
412 | */ | |
413 | regs->erp = (unsigned long) ka->sa.sa_handler; | |
414 | regs->srp = return_ip; | |
415 | regs->r10 = sig; | |
416 | ||
417 | /* Actually move the USP to reflect the stacked frame. */ | |
418 | wrusp((unsigned long)frame); | |
419 | ||
420 | return; | |
421 | ||
422 | give_sigsegv: | |
423 | if (sig == SIGSEGV) | |
424 | ka->sa.sa_handler = SIG_DFL; | |
425 | ||
426 | force_sig(SIGSEGV, current); | |
427 | } | |
428 | ||
429 | static void | |
430 | setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
431 | sigset_t *set, struct pt_regs * regs) | |
432 | { | |
433 | int err; | |
434 | unsigned long return_ip; | |
435 | struct rt_signal_frame __user *frame; | |
436 | ||
437 | err = 0; | |
438 | frame = get_sigframe(ka, regs, sizeof(*frame)); | |
439 | ||
440 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
441 | goto give_sigsegv; | |
442 | ||
443 | /* TODO: what is the current->exec_domain stuff and invmap ? */ | |
444 | ||
445 | err |= __put_user(&frame->info, &frame->pinfo); | |
446 | err |= __put_user(&frame->uc, &frame->puc); | |
447 | err |= copy_siginfo_to_user(&frame->info, info); | |
448 | ||
449 | if (err) | |
450 | goto give_sigsegv; | |
451 | ||
452 | /* Clear all the bits of the ucontext we don't use. */ | |
453 | err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext)); | |
454 | err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]); | |
455 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
456 | ||
457 | if (err) | |
458 | goto give_sigsegv; | |
459 | ||
460 | /* | |
461 | * Set up to return from user-space. If provided, use a stub | |
462 | * already located in user-space. | |
463 | */ | |
464 | if (ka->sa.sa_flags & SA_RESTORER) { | |
465 | return_ip = (unsigned long) ka->sa.sa_restorer; | |
466 | } else { | |
467 | /* Trampoline - the desired return ip is in the signal return page. */ | |
468 | return_ip = cris_signal_return_page + 6; | |
469 | ||
470 | /* | |
471 | * This is movu.w __NR_rt_sigreturn, r9; break 13; | |
472 | * | |
473 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
474 | * reasons and because gdb uses it as a signature to notice | |
475 | * signal handler stack frames. | |
476 | */ | |
477 | err |= __put_user(0x9c5f, (short __user*)(frame->retcode+0)); | |
478 | ||
479 | err |= __put_user(__NR_rt_sigreturn, | |
480 | (short __user*)(frame->retcode+2)); | |
481 | ||
482 | err |= __put_user(0xe93d, (short __user*)(frame->retcode+4)); | |
483 | } | |
484 | ||
485 | if (err) | |
486 | goto give_sigsegv; | |
487 | ||
488 | /* | |
489 | * Set up registers for signal handler. | |
490 | * | |
491 | * Where the code enters now. | |
492 | * Where the code enters later. | |
493 | * First argument is signo. | |
494 | * Second argument is (siginfo_t *). | |
495 | * Third argument is unused. | |
496 | */ | |
497 | regs->erp = (unsigned long) ka->sa.sa_handler; | |
498 | regs->srp = return_ip; | |
499 | regs->r10 = sig; | |
500 | regs->r11 = (unsigned long) &frame->info; | |
501 | regs->r12 = 0; | |
502 | ||
503 | /* Actually move the usp to reflect the stacked frame. */ | |
504 | wrusp((unsigned long)frame); | |
505 | ||
506 | return; | |
507 | ||
508 | give_sigsegv: | |
509 | if (sig == SIGSEGV) | |
510 | ka->sa.sa_handler = SIG_DFL; | |
511 | ||
512 | force_sig(SIGSEGV, current); | |
513 | } | |
514 | ||
515 | /* Invoke a singal handler to, well, handle the signal. */ | |
d9b5444e | 516 | static inline void |
51533b61 MS |
517 | handle_signal(int canrestart, unsigned long sig, |
518 | siginfo_t *info, struct k_sigaction *ka, | |
519 | sigset_t *oldset, struct pt_regs * regs) | |
520 | { | |
521 | /* Check if this got called from a system call. */ | |
522 | if (canrestart) { | |
523 | /* If so, check system call restarting. */ | |
524 | switch (regs->r10) { | |
525 | case -ERESTART_RESTARTBLOCK: | |
526 | case -ERESTARTNOHAND: | |
527 | /* | |
528 | * This means that the syscall should | |
529 | * only be restarted if there was no | |
530 | * handler for the signal, and since | |
531 | * this point isn't reached unless | |
532 | * there is a handler, there's no need | |
533 | * to restart. | |
534 | */ | |
535 | regs->r10 = -EINTR; | |
536 | break; | |
537 | ||
538 | case -ERESTARTSYS: | |
539 | /* | |
540 | * This means restart the syscall if | |
541 | * there is no handler, or the handler | |
542 | * was registered with SA_RESTART. | |
543 | */ | |
544 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
545 | regs->r10 = -EINTR; | |
546 | break; | |
547 | } | |
548 | ||
549 | /* Fall through. */ | |
550 | ||
551 | case -ERESTARTNOINTR: | |
552 | /* | |
553 | * This means that the syscall should | |
554 | * be called again after the signal | |
555 | * handler returns. | |
556 | */ | |
557 | RESTART_CRIS_SYS(regs); | |
558 | break; | |
559 | } | |
560 | } | |
561 | ||
562 | /* Set up the stack frame. */ | |
563 | if (ka->sa.sa_flags & SA_SIGINFO) | |
564 | setup_rt_frame(sig, ka, info, oldset, regs); | |
565 | else | |
566 | setup_frame(sig, ka, oldset, regs); | |
567 | ||
568 | if (ka->sa.sa_flags & SA_ONESHOT) | |
569 | ka->sa.sa_handler = SIG_DFL; | |
570 | ||
69be8f18 SR |
571 | spin_lock_irq(¤t->sighand->siglock); |
572 | sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); | |
573 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
51533b61 | 574 | sigaddset(¤t->blocked,sig); |
69be8f18 SR |
575 | recalc_sigpending(); |
576 | spin_unlock_irq(¤t->sighand->siglock); | |
51533b61 MS |
577 | } |
578 | ||
579 | /* | |
580 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
581 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
582 | * mistake. | |
583 | * | |
584 | * Also note that the regs structure given here as an argument, is the latest | |
585 | * pushed pt_regs. It may or may not be the same as the first pushed registers | |
586 | * when the initial usermode->kernelmode transition took place. Therefore | |
587 | * we can use user_mode(regs) to see if we came directly from kernel or user | |
588 | * mode below. | |
589 | */ | |
590 | int | |
591 | do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs) | |
592 | { | |
593 | int signr; | |
594 | siginfo_t info; | |
595 | struct k_sigaction ka; | |
596 | ||
597 | /* | |
598 | * The common case should go fast, which is why this point is | |
599 | * reached from kernel-mode. If that's the case, just return | |
600 | * without doing anything. | |
601 | */ | |
602 | if (!user_mode(regs)) | |
603 | return 1; | |
604 | ||
605 | if (!oldset) | |
606 | oldset = ¤t->blocked; | |
607 | ||
608 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
609 | ||
610 | if (signr > 0) { | |
611 | /* Deliver the signal. */ | |
612 | handle_signal(canrestart, signr, &info, &ka, oldset, regs); | |
613 | return 1; | |
614 | } | |
615 | ||
616 | /* Got here from a system call? */ | |
617 | if (canrestart) { | |
618 | /* Restart the system call - no handlers present. */ | |
619 | if (regs->r10 == -ERESTARTNOHAND || | |
620 | regs->r10 == -ERESTARTSYS || | |
621 | regs->r10 == -ERESTARTNOINTR) { | |
622 | RESTART_CRIS_SYS(regs); | |
623 | } | |
624 | ||
625 | if (regs->r10 == -ERESTART_RESTARTBLOCK){ | |
626 | regs->r10 = __NR_restart_syscall; | |
627 | regs->erp -= 2; | |
628 | } | |
629 | } | |
630 | ||
631 | return 0; | |
632 | } | |
633 | ||
634 | asmlinkage void | |
635 | ugdb_trap_user(struct thread_info *ti, int sig) | |
636 | { | |
637 | if (((user_regs(ti)->exs & 0xff00) >> 8) != SINGLE_STEP_INTR_VECT) { | |
638 | /* Zero single-step PC if the reason we stopped wasn't a single | |
639 | step exception. This is to avoid relying on it when it isn't | |
640 | reliable. */ | |
641 | user_regs(ti)->spc = 0; | |
642 | } | |
643 | /* FIXME: Filter out false h/w breakpoint hits (i.e. EDA | |
644 | not withing any configured h/w breakpoint range). Synchronize with | |
645 | what already exists for kernel debugging. */ | |
646 | if (((user_regs(ti)->exs & 0xff00) >> 8) == BREAK_8_INTR_VECT) { | |
647 | /* Break 8: subtract 2 from ERP unless in a delay slot. */ | |
648 | if (!(user_regs(ti)->erp & 0x1)) | |
649 | user_regs(ti)->erp -= 2; | |
650 | } | |
651 | sys_kill(ti->task->pid, sig); | |
652 | } | |
653 | ||
654 | void | |
655 | keep_debug_flags(unsigned long oldccs, unsigned long oldspc, | |
656 | struct pt_regs *regs) | |
657 | { | |
658 | if (oldccs & (1 << Q_CCS_BITNR)) { | |
659 | /* Pending single step due to single-stepping the break 13 | |
660 | in the signal trampoline: keep the Q flag. */ | |
661 | regs->ccs |= (1 << Q_CCS_BITNR); | |
662 | /* S flag should be set - complain if it's not. */ | |
663 | if (!(oldccs & (1 << (S_CCS_BITNR + CCS_SHIFT)))) { | |
664 | printk("Q flag but no S flag?"); | |
665 | } | |
666 | regs->ccs |= (1 << (S_CCS_BITNR + CCS_SHIFT)); | |
667 | /* Assume the SPC is valid and interesting. */ | |
668 | regs->spc = oldspc; | |
669 | ||
670 | } else if (oldccs & (1 << (S_CCS_BITNR + CCS_SHIFT))) { | |
671 | /* If a h/w bp was set in the signal handler we need | |
672 | to keep the S flag. */ | |
673 | regs->ccs |= (1 << (S_CCS_BITNR + CCS_SHIFT)); | |
674 | /* Don't keep the old SPC though; if we got here due to | |
675 | a single-step, the Q flag should have been set. */ | |
676 | } else if (regs->spc) { | |
677 | /* If we were single-stepping *before* the signal was taken, | |
678 | we don't want to restore that state now, because GDB will | |
679 | have forgotten all about it. */ | |
680 | regs->spc = 0; | |
681 | regs->ccs &= ~(1 << (S_CCS_BITNR + CCS_SHIFT)); | |
682 | } | |
683 | } | |
684 | ||
685 | /* Set up the trampolines on the signal return page. */ | |
686 | int __init | |
687 | cris_init_signal(void) | |
688 | { | |
5cbded58 | 689 | u16* data = kmalloc(PAGE_SIZE, GFP_KERNEL); |
51533b61 MS |
690 | |
691 | /* This is movu.w __NR_sigreturn, r9; break 13; */ | |
692 | data[0] = 0x9c5f; | |
693 | data[1] = __NR_sigreturn; | |
694 | data[2] = 0xe93d; | |
695 | /* This is movu.w __NR_rt_sigreturn, r9; break 13; */ | |
696 | data[3] = 0x9c5f; | |
697 | data[4] = __NR_rt_sigreturn; | |
698 | data[5] = 0xe93d; | |
699 | ||
700 | /* Map to userspace with appropriate permissions (no write access...) */ | |
701 | cris_signal_return_page = (unsigned long) | |
702 | __ioremap_prot(virt_to_phys(data), PAGE_SIZE, PAGE_SIGNAL_TRAMPOLINE); | |
703 | ||
704 | return 0; | |
705 | } | |
706 | ||
707 | __initcall(cris_init_signal); |