1 /* signal.c: FRV specific bits of signal handling
3 * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 * - Derived from arch/m68k/kernel/signal.c
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
13 #include <linux/sched.h>
15 #include <linux/smp.h>
16 #include <linux/kernel.h>
17 #include <linux/signal.h>
18 #include <linux/errno.h>
19 #include <linux/wait.h>
20 #include <linux/ptrace.h>
21 #include <linux/unistd.h>
22 #include <linux/personality.h>
23 #include <linux/freezer.h>
24 #include <linux/tracehook.h>
25 #include <asm/ucontext.h>
26 #include <asm/uaccess.h>
27 #include <asm/cacheflush.h>
31 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
33 struct fdpic_func_descriptor {
39 * Atomically swap in the new signal mask, and wait for a signal.
41 asmlinkage int sys_sigsuspend(int history0, int history1, old_sigset_t mask)
44 siginitset(&blocked, mask);
45 return sigsuspend(&blocked);
48 asmlinkage int sys_sigaction(int sig,
49 const struct old_sigaction __user *act,
50 struct old_sigaction __user *oact)
52 struct k_sigaction new_ka, old_ka;
57 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
58 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
59 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
60 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
61 __get_user(mask, &act->sa_mask))
63 siginitset(&new_ka.sa.sa_mask, mask);
66 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
69 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
70 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
71 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
72 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
73 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
81 int sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
83 return do_sigaltstack(uss, uoss, __frame->sp);
88 * Do a signal return; undo the signal stack.
93 __sigrestore_t pretcode;
96 unsigned long extramask[_NSIG_WORDS-1];
102 __sigrestore_t pretcode;
104 struct siginfo __user *pinfo;
111 static int restore_sigcontext(struct sigcontext __user *sc, int *_gr8)
113 struct user_context *user = current->thread.user;
114 unsigned long tbr, psr;
116 /* Always make any pending restarted system calls return -EINTR */
117 current_thread_info()->restart_block.fn = do_no_restart_syscall;
121 if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))
126 restore_user_regs(user);
128 user->i.syscallno = -1; /* disable syscall checks */
130 *_gr8 = user->i.gr[8];
137 asmlinkage int sys_sigreturn(void)
139 struct sigframe __user *frame = (struct sigframe __user *) __frame->sp;
143 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
145 if (__get_user(set.sig[0], &frame->sc.sc_oldmask))
148 if (_NSIG_WORDS > 1 &&
149 __copy_from_user(&set.sig[1], &frame->extramask, sizeof(frame->extramask)))
152 sigdelsetmask(&set, ~_BLOCKABLE);
153 set_current_blocked(&set);
155 if (restore_sigcontext(&frame->sc, &gr8))
160 force_sig(SIGSEGV, current);
164 asmlinkage int sys_rt_sigreturn(void)
166 struct rt_sigframe __user *frame = (struct rt_sigframe __user *) __frame->sp;
170 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
172 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
175 sigdelsetmask(&set, ~_BLOCKABLE);
176 set_current_blocked(&set);
178 if (restore_sigcontext(&frame->uc.uc_mcontext, &gr8))
181 if (do_sigaltstack(&frame->uc.uc_stack, NULL, __frame->sp) == -EFAULT)
187 force_sig(SIGSEGV, current);
192 * Set up a signal frame
194 static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
196 save_user_regs(current->thread.user);
198 if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
201 /* non-iBCS2 extensions.. */
202 if (__put_user(mask, &sc->sc_oldmask) < 0)
211 /*****************************************************************************/
213 * Determine which stack to use..
215 static inline void __user *get_sigframe(struct k_sigaction *ka,
220 /* Default to using normal stack */
223 /* This is the X/Open sanctioned signal stack switching. */
224 if (ka->sa.sa_flags & SA_ONSTACK) {
225 if (! sas_ss_flags(sp))
226 sp = current->sas_ss_sp + current->sas_ss_size;
229 return (void __user *) ((sp - frame_size) & ~7UL);
231 } /* end get_sigframe() */
233 /*****************************************************************************/
237 static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set)
239 struct sigframe __user *frame;
244 frame = get_sigframe(ka, sizeof(*frame));
246 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
251 __current_thread_info->exec_domain &&
252 __current_thread_info->exec_domain->signal_invmap)
253 rsig = __current_thread_info->exec_domain->signal_invmap[sig];
255 if (__put_user(rsig, &frame->sig) < 0)
258 if (setup_sigcontext(&frame->sc, set->sig[0]))
261 if (_NSIG_WORDS > 1) {
262 if (__copy_to_user(frame->extramask, &set->sig[1],
263 sizeof(frame->extramask)))
267 /* Set up to return from userspace. If provided, use a stub
268 * already in userspace. */
269 if (ka->sa.sa_flags & SA_RESTORER) {
270 if (__put_user(ka->sa.sa_restorer, &frame->pretcode) < 0)
274 /* Set up the following code on the stack:
275 * setlos #__NR_sigreturn,gr7
278 if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
279 __put_user(0x8efc0000|__NR_sigreturn, &frame->retcode[0]) ||
280 __put_user(0xc0700000, &frame->retcode[1]))
283 flush_icache_range((unsigned long) frame->retcode,
284 (unsigned long) (frame->retcode + 2));
287 /* Set up registers for the signal handler */
288 if (current->personality & FDPIC_FUNCPTRS) {
289 struct fdpic_func_descriptor __user *funcptr =
290 (struct fdpic_func_descriptor __user *) ka->sa.sa_handler;
291 struct fdpic_func_descriptor desc;
292 if (copy_from_user(&desc, funcptr, sizeof(desc)))
294 __frame->pc = desc.text;
295 __frame->gr15 = desc.GOT;
297 __frame->pc = (unsigned long) ka->sa.sa_handler;
301 __frame->sp = (unsigned long) frame;
302 __frame->lr = (unsigned long) &frame->retcode;
305 /* the tracer may want to single-step inside the handler */
306 if (test_thread_flag(TIF_SINGLESTEP))
307 ptrace_notify(SIGTRAP);
310 printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
311 sig, current->comm, current->pid, frame, __frame->pc,
318 force_sigsegv(sig, current);
321 } /* end setup_frame() */
323 /*****************************************************************************/
327 static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
330 struct rt_sigframe __user *frame;
335 frame = get_sigframe(ka, sizeof(*frame));
337 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
342 __current_thread_info->exec_domain &&
343 __current_thread_info->exec_domain->signal_invmap)
344 rsig = __current_thread_info->exec_domain->signal_invmap[sig];
346 if (__put_user(rsig, &frame->sig) ||
347 __put_user(&frame->info, &frame->pinfo) ||
348 __put_user(&frame->uc, &frame->puc))
351 if (copy_siginfo_to_user(&frame->info, info))
354 /* Create the ucontext. */
355 if (__put_user(0, &frame->uc.uc_flags) ||
356 __put_user(NULL, &frame->uc.uc_link) ||
357 __put_user((void __user *)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp) ||
358 __put_user(sas_ss_flags(__frame->sp), &frame->uc.uc_stack.ss_flags) ||
359 __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size))
362 if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
365 if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
368 /* Set up to return from userspace. If provided, use a stub
369 * already in userspace. */
370 if (ka->sa.sa_flags & SA_RESTORER) {
371 if (__put_user(ka->sa.sa_restorer, &frame->pretcode))
375 /* Set up the following code on the stack:
376 * setlos #__NR_sigreturn,gr7
379 if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
380 __put_user(0x8efc0000|__NR_rt_sigreturn, &frame->retcode[0]) ||
381 __put_user(0xc0700000, &frame->retcode[1]))
384 flush_icache_range((unsigned long) frame->retcode,
385 (unsigned long) (frame->retcode + 2));
388 /* Set up registers for signal handler */
389 if (current->personality & FDPIC_FUNCPTRS) {
390 struct fdpic_func_descriptor __user *funcptr =
391 (struct fdpic_func_descriptor __user *) ka->sa.sa_handler;
392 struct fdpic_func_descriptor desc;
393 if (copy_from_user(&desc, funcptr, sizeof(desc)))
395 __frame->pc = desc.text;
396 __frame->gr15 = desc.GOT;
398 __frame->pc = (unsigned long) ka->sa.sa_handler;
402 __frame->sp = (unsigned long) frame;
403 __frame->lr = (unsigned long) &frame->retcode;
405 __frame->gr9 = (unsigned long) &frame->info;
407 /* the tracer may want to single-step inside the handler */
408 if (test_thread_flag(TIF_SINGLESTEP))
409 ptrace_notify(SIGTRAP);
412 printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
413 sig, current->comm, current->pid, frame, __frame->pc,
420 force_sigsegv(sig, current);
423 } /* end setup_rt_frame() */
425 /*****************************************************************************/
427 * OK, we're invoking a handler
429 static int handle_signal(unsigned long sig, siginfo_t *info,
430 struct k_sigaction *ka, sigset_t *oldset)
434 /* Are we from a system call? */
435 if (__frame->syscallno != -1) {
436 /* If so, check system call restarting.. */
437 switch (__frame->gr8) {
438 case -ERESTART_RESTARTBLOCK:
439 case -ERESTARTNOHAND:
440 __frame->gr8 = -EINTR;
444 if (!(ka->sa.sa_flags & SA_RESTART)) {
445 __frame->gr8 = -EINTR;
450 case -ERESTARTNOINTR:
451 __frame->gr8 = __frame->orig_gr8;
454 __frame->syscallno = -1;
457 /* Set up the stack frame */
458 if (ka->sa.sa_flags & SA_SIGINFO)
459 ret = setup_rt_frame(sig, ka, info, oldset);
461 ret = setup_frame(sig, ka, oldset);
464 block_sigmask(ka, sig);
468 } /* end handle_signal() */
470 /*****************************************************************************/
472 * Note that 'init' is a special process: it doesn't get signals it doesn't
473 * want to handle. Thus you cannot kill init even with a SIGKILL even by
476 static void do_signal(void)
478 struct k_sigaction ka;
484 * We want the common case to go fast, which
485 * is why we may in certain cases get here from
486 * kernel mode. Just return without doing anything
489 if (!user_mode(__frame))
495 if (test_thread_flag(TIF_RESTORE_SIGMASK))
496 oldset = ¤t->saved_sigmask;
498 oldset = ¤t->blocked;
500 signr = get_signal_to_deliver(&info, &ka, __frame, NULL);
502 if (handle_signal(signr, &info, &ka, oldset) == 0) {
503 /* a signal was successfully delivered; the saved
504 * sigmask will have been stored in the signal frame,
505 * and will be restored by sigreturn, so we can simply
506 * clear the TIF_RESTORE_SIGMASK flag */
507 if (test_thread_flag(TIF_RESTORE_SIGMASK))
508 clear_thread_flag(TIF_RESTORE_SIGMASK);
510 tracehook_signal_handler(signr, &info, &ka, __frame,
511 test_thread_flag(TIF_SINGLESTEP));
518 /* Did we come from a system call? */
519 if (__frame->syscallno != -1) {
520 /* Restart the system call - no handlers present */
521 switch (__frame->gr8) {
522 case -ERESTARTNOHAND:
524 case -ERESTARTNOINTR:
525 __frame->gr8 = __frame->orig_gr8;
529 case -ERESTART_RESTARTBLOCK:
530 __frame->gr7 = __NR_restart_syscall;
534 __frame->syscallno = -1;
537 /* if there's no signal to deliver, we just put the saved sigmask
539 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
540 clear_thread_flag(TIF_RESTORE_SIGMASK);
541 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
544 } /* end do_signal() */
546 /*****************************************************************************/
548 * notification of userspace execution resumption
549 * - triggered by the TIF_WORK_MASK flags
551 asmlinkage void do_notify_resume(__u32 thread_info_flags)
553 /* pending single-step? */
554 if (thread_info_flags & _TIF_SINGLESTEP)
555 clear_thread_flag(TIF_SINGLESTEP);
557 /* deal with pending signal delivery */
558 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
561 /* deal with notification on about to resume userspace execution */
562 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
563 clear_thread_flag(TIF_NOTIFY_RESUME);
564 tracehook_notify_resume(__frame);
567 } /* end do_notify_resume() */