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/smp_lock.h>
17 #include <linux/kernel.h>
18 #include <linux/signal.h>
19 #include <linux/errno.h>
20 #include <linux/wait.h>
21 #include <linux/ptrace.h>
22 #include <linux/unistd.h>
23 #include <linux/personality.h>
24 #include <linux/suspend.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 {
38 asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset);
41 * Atomically swap in the new signal mask, and wait for a signal.
43 asmlinkage int sys_sigsuspend(int history0, int history1, old_sigset_t mask)
48 spin_lock_irq(¤t->sighand->siglock);
49 saveset = current->blocked;
50 siginitset(¤t->blocked, mask);
52 spin_unlock_irq(¤t->sighand->siglock);
54 __frame->gr8 = -EINTR;
56 current->state = TASK_INTERRUPTIBLE;
58 if (do_signal(__frame, &saveset))
59 /* return the signal number as the return value of this function
60 * - this is an utterly evil hack. syscalls should not invoke do_signal()
61 * as entry.S sets regs->gr8 to the return value of the system call
62 * - we can't just use sigpending() as we'd have to discard SIG_IGN signals
63 * and call waitpid() if SIGCHLD needed discarding
64 * - this only works on the i386 because it passes arguments to the signal
65 * handler on the stack, and the return value in EAX is effectively
72 asmlinkage int sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize)
74 sigset_t saveset, newset;
76 /* XXX: Don't preclude handling different sized sigset_t's. */
77 if (sigsetsize != sizeof(sigset_t))
80 if (copy_from_user(&newset, unewset, sizeof(newset)))
82 sigdelsetmask(&newset, ~_BLOCKABLE);
84 spin_lock_irq(¤t->sighand->siglock);
85 saveset = current->blocked;
86 current->blocked = newset;
88 spin_unlock_irq(¤t->sighand->siglock);
90 __frame->gr8 = -EINTR;
92 current->state = TASK_INTERRUPTIBLE;
94 if (do_signal(__frame, &saveset))
95 /* return the signal number as the return value of this function
96 * - this is an utterly evil hack. syscalls should not invoke do_signal()
97 * as entry.S sets regs->gr8 to the return value of the system call
98 * - we can't just use sigpending() as we'd have to discard SIG_IGN signals
99 * and call waitpid() if SIGCHLD needed discarding
100 * - this only works on the i386 because it passes arguments to the signal
101 * handler on the stack, and the return value in EAX is effectively
108 asmlinkage int sys_sigaction(int sig,
109 const struct old_sigaction __user *act,
110 struct old_sigaction __user *oact)
112 struct k_sigaction new_ka, old_ka;
117 if (verify_area(VERIFY_READ, act, sizeof(*act)) ||
118 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
119 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
121 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
122 __get_user(mask, &act->sa_mask);
123 siginitset(&new_ka.sa.sa_mask, mask);
126 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
129 if (verify_area(VERIFY_WRITE, oact, sizeof(*oact)) ||
130 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
131 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
133 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
134 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
141 int sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
143 return do_sigaltstack(uss, uoss, __frame->sp);
148 * Do a signal return; undo the signal stack.
153 void (*pretcode)(void);
155 struct sigcontext sc;
156 unsigned long extramask[_NSIG_WORDS-1];
162 void (*pretcode)(void);
164 struct siginfo *pinfo;
171 static int restore_sigcontext(struct sigcontext __user *sc, int *_gr8)
173 struct user_context *user = current->thread.user;
174 unsigned long tbr, psr;
178 if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))
183 restore_user_regs(user);
185 user->i.syscallno = -1; /* disable syscall checks */
187 *_gr8 = user->i.gr[8];
194 asmlinkage int sys_sigreturn(void)
196 struct sigframe __user *frame = (struct sigframe __user *) __frame->sp;
200 if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
202 if (__get_user(set.sig[0], &frame->sc.sc_oldmask))
205 if (_NSIG_WORDS > 1 &&
206 __copy_from_user(&set.sig[1], &frame->extramask, sizeof(frame->extramask)))
209 sigdelsetmask(&set, ~_BLOCKABLE);
210 spin_lock_irq(¤t->sighand->siglock);
211 current->blocked = set;
213 spin_unlock_irq(¤t->sighand->siglock);
215 if (restore_sigcontext(&frame->sc, &gr8))
220 force_sig(SIGSEGV, current);
224 asmlinkage int sys_rt_sigreturn(void)
226 struct rt_sigframe __user *frame = (struct rt_sigframe __user *) __frame->sp;
231 if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
233 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
236 sigdelsetmask(&set, ~_BLOCKABLE);
237 spin_lock_irq(¤t->sighand->siglock);
238 current->blocked = set;
240 spin_unlock_irq(¤t->sighand->siglock);
242 if (restore_sigcontext(&frame->uc.uc_mcontext, &gr8))
245 if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
248 /* It is more difficult to avoid calling this function than to
249 * call it and ignore errors. */
251 * THIS CANNOT WORK! "&st" is a kernel address, and "do_sigaltstack()"
252 * takes a user address (and verifies that it is a user address). End
253 * result: it does exactly _nothing_.
255 do_sigaltstack(&st, NULL, __frame->sp);
260 force_sig(SIGSEGV, current);
265 * Set up a signal frame
267 static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
269 save_user_regs(current->thread.user);
271 if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
274 /* non-iBCS2 extensions.. */
275 if (__put_user(mask, &sc->sc_oldmask) < 0)
284 /*****************************************************************************/
286 * Determine which stack to use..
288 static inline void __user *get_sigframe(struct k_sigaction *ka,
289 struct pt_regs *regs,
294 /* Default to using normal stack */
297 /* This is the X/Open sanctioned signal stack switching. */
298 if (ka->sa.sa_flags & SA_ONSTACK) {
299 if (! on_sig_stack(sp))
300 sp = current->sas_ss_sp + current->sas_ss_size;
303 return (void __user *) ((sp - frame_size) & ~7UL);
304 } /* end get_sigframe() */
306 /*****************************************************************************/
310 static void setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, struct pt_regs * regs)
312 struct sigframe __user *frame;
315 frame = get_sigframe(ka, regs, sizeof(*frame));
317 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
322 __current_thread_info->exec_domain &&
323 __current_thread_info->exec_domain->signal_invmap)
324 rsig = __current_thread_info->exec_domain->signal_invmap[sig];
326 if (__put_user(rsig, &frame->sig) < 0)
329 if (setup_sigcontext(&frame->sc, set->sig[0]))
332 if (_NSIG_WORDS > 1) {
333 if (__copy_to_user(frame->extramask, &set->sig[1],
334 sizeof(frame->extramask)))
338 /* Set up to return from userspace. If provided, use a stub
339 * already in userspace. */
340 if (ka->sa.sa_flags & SA_RESTORER) {
341 if (__put_user(ka->sa.sa_restorer, &frame->pretcode) < 0)
345 /* Set up the following code on the stack:
346 * setlos #__NR_sigreturn,gr7
349 if (__put_user((void (*)(void))frame->retcode, &frame->pretcode) ||
350 __put_user(0x8efc0000|__NR_sigreturn, &frame->retcode[0]) ||
351 __put_user(0xc0700000, &frame->retcode[1]))
354 flush_icache_range((unsigned long) frame->retcode,
355 (unsigned long) (frame->retcode + 2));
358 /* set up registers for signal handler */
359 regs->sp = (unsigned long) frame;
360 regs->lr = (unsigned long) &frame->retcode;
363 if (get_personality & FDPIC_FUNCPTRS) {
364 struct fdpic_func_descriptor __user *funcptr =
365 (struct fdpic_func_descriptor *) ka->sa.sa_handler;
366 __get_user(regs->pc, &funcptr->text);
367 __get_user(regs->gr15, &funcptr->GOT);
369 regs->pc = (unsigned long) ka->sa.sa_handler;
376 printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
377 sig, current->comm, current->pid, frame, regs->pc, frame->pretcode);
384 ka->sa.sa_handler = SIG_DFL;
386 force_sig(SIGSEGV, current);
387 } /* end setup_frame() */
389 /*****************************************************************************/
393 static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
394 sigset_t *set, struct pt_regs * regs)
396 struct rt_sigframe __user *frame;
399 frame = get_sigframe(ka, regs, sizeof(*frame));
401 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
406 __current_thread_info->exec_domain &&
407 __current_thread_info->exec_domain->signal_invmap)
408 rsig = __current_thread_info->exec_domain->signal_invmap[sig];
410 if (__put_user(rsig, &frame->sig) ||
411 __put_user(&frame->info, &frame->pinfo) ||
412 __put_user(&frame->uc, &frame->puc))
415 if (copy_siginfo_to_user(&frame->info, info))
418 /* Create the ucontext. */
419 if (__put_user(0, &frame->uc.uc_flags) ||
420 __put_user(0, &frame->uc.uc_link) ||
421 __put_user((void*)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp) ||
422 __put_user(sas_ss_flags(regs->sp), &frame->uc.uc_stack.ss_flags) ||
423 __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size))
426 if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
429 if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
432 /* Set up to return from userspace. If provided, use a stub
433 * already in userspace. */
434 if (ka->sa.sa_flags & SA_RESTORER) {
435 if (__put_user(ka->sa.sa_restorer, &frame->pretcode))
439 /* Set up the following code on the stack:
440 * setlos #__NR_sigreturn,gr7
443 if (__put_user((void (*)(void))frame->retcode, &frame->pretcode) ||
444 __put_user(0x8efc0000|__NR_rt_sigreturn, &frame->retcode[0]) ||
445 __put_user(0xc0700000, &frame->retcode[1]))
448 flush_icache_range((unsigned long) frame->retcode,
449 (unsigned long) (frame->retcode + 2));
452 /* Set up registers for signal handler */
453 regs->sp = (unsigned long) frame;
454 regs->lr = (unsigned long) &frame->retcode;
456 regs->gr9 = (unsigned long) &frame->info;
458 if (get_personality & FDPIC_FUNCPTRS) {
459 struct fdpic_func_descriptor *funcptr =
460 (struct fdpic_func_descriptor __user *) ka->sa.sa_handler;
461 __get_user(regs->pc, &funcptr->text);
462 __get_user(regs->gr15, &funcptr->GOT);
464 regs->pc = (unsigned long) ka->sa.sa_handler;
471 printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
472 sig, current->comm, current->pid, frame, regs->pc, frame->pretcode);
479 ka->sa.sa_handler = SIG_DFL;
480 force_sig(SIGSEGV, current);
482 } /* end setup_rt_frame() */
484 /*****************************************************************************/
486 * OK, we're invoking a handler
488 static void handle_signal(unsigned long sig, siginfo_t *info,
489 struct k_sigaction *ka, sigset_t *oldset,
490 struct pt_regs *regs)
492 /* Are we from a system call? */
493 if (in_syscall(regs)) {
494 /* If so, check system call restarting.. */
496 case -ERESTART_RESTARTBLOCK:
497 case -ERESTARTNOHAND:
502 if (!(ka->sa.sa_flags & SA_RESTART)) {
507 case -ERESTARTNOINTR:
508 regs->gr8 = regs->orig_gr8;
513 /* Set up the stack frame */
514 if (ka->sa.sa_flags & SA_SIGINFO)
515 setup_rt_frame(sig, ka, info, oldset, regs);
517 setup_frame(sig, ka, oldset, regs);
519 if (!(ka->sa.sa_flags & SA_NODEFER)) {
520 spin_lock_irq(¤t->sighand->siglock);
521 sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask);
522 sigaddset(¤t->blocked, sig);
524 spin_unlock_irq(¤t->sighand->siglock);
526 } /* end handle_signal() */
528 /*****************************************************************************/
530 * Note that 'init' is a special process: it doesn't get signals it doesn't
531 * want to handle. Thus you cannot kill init even with a SIGKILL even by
534 int do_signal(struct pt_regs *regs, sigset_t *oldset)
536 struct k_sigaction ka;
541 * We want the common case to go fast, which
542 * is why we may in certain cases get here from
543 * kernel mode. Just return without doing anything
546 if (!user_mode(regs))
549 if (current->flags & PF_FREEZE) {
555 oldset = ¤t->blocked;
557 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
559 handle_signal(signr, &info, &ka, oldset, regs);
564 /* Did we come from a system call? */
565 if (regs->syscallno >= 0) {
566 /* Restart the system call - no handlers present */
567 if (regs->gr8 == -ERESTARTNOHAND ||
568 regs->gr8 == -ERESTARTSYS ||
569 regs->gr8 == -ERESTARTNOINTR) {
570 regs->gr8 = regs->orig_gr8;
574 if (regs->gr8 == -ERESTART_RESTARTBLOCK){
575 regs->gr8 = __NR_restart_syscall;
581 } /* end do_signal() */
583 /*****************************************************************************/
585 * notification of userspace execution resumption
586 * - triggered by current->work.notify_resume
588 asmlinkage void do_notify_resume(__u32 thread_info_flags)
590 /* pending single-step? */
591 if (thread_info_flags & _TIF_SINGLESTEP)
592 clear_thread_flag(TIF_SINGLESTEP);
594 /* deal with pending signal delivery */
595 if (thread_info_flags & _TIF_SIGPENDING)
596 do_signal(__frame, NULL);
598 } /* end do_notify_resume() */