2 * linux/arch/alpha/kernel/signal.c
4 * Copyright (C) 1995 Linus Torvalds
6 * 1997-11-02 Modified for POSIX.1b signals by Richard Henderson
9 #include <linux/sched.h>
10 #include <linux/kernel.h>
11 #include <linux/signal.h>
12 #include <linux/errno.h>
13 #include <linux/wait.h>
14 #include <linux/ptrace.h>
15 #include <linux/unistd.h>
17 #include <linux/smp.h>
18 #include <linux/smp_lock.h>
19 #include <linux/stddef.h>
20 #include <linux/tty.h>
21 #include <linux/binfmts.h>
23 #include <asm/bitops.h>
24 #include <asm/uaccess.h>
25 #include <asm/sigcontext.h>
26 #include <asm/ucontext.h>
33 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
35 asmlinkage void ret_from_sys_call(void);
36 static int do_signal(sigset_t *, struct pt_regs *, struct switch_stack *,
37 unsigned long, unsigned long);
41 * The OSF/1 sigprocmask calling sequence is different from the
42 * C sigprocmask() sequence..
49 * We change the range to -1 .. 1 in order to let gcc easily
50 * use the conditional move instructions.
52 * Note that we don't need to acquire the kernel lock for SMP
53 * operation, as all of this is local to this thread.
55 asmlinkage unsigned long
56 osf_sigprocmask(int how, unsigned long newmask, long a2, long a3,
57 long a4, long a5, struct pt_regs regs)
59 unsigned long oldmask = -EINVAL;
61 if ((unsigned long)how-1 <= 2) {
62 long sign = how-2; /* -1 .. 1 */
63 unsigned long block, unblock;
65 newmask &= _BLOCKABLE;
66 spin_lock_irq(¤t->sighand->siglock);
67 oldmask = current->blocked.sig[0];
69 unblock = oldmask & ~newmask;
70 block = oldmask | newmask;
75 if (_NSIG_WORDS > 1 && sign > 0)
76 sigemptyset(¤t->blocked);
77 current->blocked.sig[0] = newmask;
79 spin_unlock_irq(¤t->sighand->siglock);
81 (®s)->r0 = 0; /* special no error return */
87 osf_sigaction(int sig, const struct osf_sigaction *act,
88 struct osf_sigaction *oact)
90 struct k_sigaction new_ka, old_ka;
95 if (verify_area(VERIFY_READ, act, sizeof(*act)) ||
96 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
97 __get_user(new_ka.sa.sa_flags, &act->sa_flags))
99 __get_user(mask, &act->sa_mask);
100 siginitset(&new_ka.sa.sa_mask, mask);
101 new_ka.ka_restorer = NULL;
104 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
107 if (verify_area(VERIFY_WRITE, oact, sizeof(*oact)) ||
108 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
109 __put_user(old_ka.sa.sa_flags, &oact->sa_flags))
111 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
118 sys_rt_sigaction(int sig, const struct sigaction *act, struct sigaction *oact,
119 size_t sigsetsize, void *restorer)
121 struct k_sigaction new_ka, old_ka;
124 /* XXX: Don't preclude handling different sized sigset_t's. */
125 if (sigsetsize != sizeof(sigset_t))
129 new_ka.ka_restorer = restorer;
130 if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
134 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
137 if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
145 * Atomically swap in the new signal mask, and wait for a signal.
148 do_sigsuspend(old_sigset_t mask, struct pt_regs *reg, struct switch_stack *sw)
153 spin_lock_irq(¤t->sighand->siglock);
154 oldset = current->blocked;
155 siginitset(¤t->blocked, mask);
157 spin_unlock_irq(¤t->sighand->siglock);
160 current->state = TASK_INTERRUPTIBLE;
162 if (do_signal(&oldset, reg, sw, 0, 0))
168 do_rt_sigsuspend(sigset_t *uset, size_t sigsetsize,
169 struct pt_regs *reg, struct switch_stack *sw)
171 sigset_t oldset, set;
173 /* XXX: Don't preclude handling different sized sigset_t's. */
174 if (sigsetsize != sizeof(sigset_t))
176 if (copy_from_user(&set, uset, sizeof(set)))
179 sigdelsetmask(&set, ~_BLOCKABLE);
180 spin_lock_irq(¤t->sighand->siglock);
181 oldset = current->blocked;
182 current->blocked = set;
184 spin_unlock_irq(¤t->sighand->siglock);
187 current->state = TASK_INTERRUPTIBLE;
189 if (do_signal(&oldset, reg, sw, 0, 0))
195 sys_sigaltstack(const stack_t *uss, stack_t *uoss)
197 return do_sigaltstack(uss, uoss, rdusp());
201 * Do a signal return; undo the signal stack.
205 # error "Non SA_SIGINFO frame needs rearranging"
210 struct sigcontext sc;
211 unsigned int retcode[3];
218 unsigned int retcode[3];
221 #define INSN_MOV_R30_R16 0x47fe0410
222 #define INSN_LDI_R0 0x201f0000
223 #define INSN_CALLSYS 0x00000083
226 restore_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
227 struct switch_stack *sw)
230 long i, err = __get_user(regs->pc, &sc->sc_pc);
232 sw->r26 = (unsigned long) ret_from_sys_call;
234 err |= __get_user(regs->r0, sc->sc_regs+0);
235 err |= __get_user(regs->r1, sc->sc_regs+1);
236 err |= __get_user(regs->r2, sc->sc_regs+2);
237 err |= __get_user(regs->r3, sc->sc_regs+3);
238 err |= __get_user(regs->r4, sc->sc_regs+4);
239 err |= __get_user(regs->r5, sc->sc_regs+5);
240 err |= __get_user(regs->r6, sc->sc_regs+6);
241 err |= __get_user(regs->r7, sc->sc_regs+7);
242 err |= __get_user(regs->r8, sc->sc_regs+8);
243 err |= __get_user(sw->r9, sc->sc_regs+9);
244 err |= __get_user(sw->r10, sc->sc_regs+10);
245 err |= __get_user(sw->r11, sc->sc_regs+11);
246 err |= __get_user(sw->r12, sc->sc_regs+12);
247 err |= __get_user(sw->r13, sc->sc_regs+13);
248 err |= __get_user(sw->r14, sc->sc_regs+14);
249 err |= __get_user(sw->r15, sc->sc_regs+15);
250 err |= __get_user(regs->r16, sc->sc_regs+16);
251 err |= __get_user(regs->r17, sc->sc_regs+17);
252 err |= __get_user(regs->r18, sc->sc_regs+18);
253 err |= __get_user(regs->r19, sc->sc_regs+19);
254 err |= __get_user(regs->r20, sc->sc_regs+20);
255 err |= __get_user(regs->r21, sc->sc_regs+21);
256 err |= __get_user(regs->r22, sc->sc_regs+22);
257 err |= __get_user(regs->r23, sc->sc_regs+23);
258 err |= __get_user(regs->r24, sc->sc_regs+24);
259 err |= __get_user(regs->r25, sc->sc_regs+25);
260 err |= __get_user(regs->r26, sc->sc_regs+26);
261 err |= __get_user(regs->r27, sc->sc_regs+27);
262 err |= __get_user(regs->r28, sc->sc_regs+28);
263 err |= __get_user(regs->gp, sc->sc_regs+29);
264 err |= __get_user(usp, sc->sc_regs+30);
267 for (i = 0; i < 31; i++)
268 err |= __get_user(sw->fp[i], sc->sc_fpregs+i);
269 err |= __get_user(sw->fp[31], &sc->sc_fpcr);
274 /* Note that this syscall is also used by setcontext(3) to install
275 a given sigcontext. This because it's impossible to set *all*
276 registers and transfer control from userland. */
279 do_sigreturn(struct sigcontext *sc, struct pt_regs *regs,
280 struct switch_stack *sw)
284 /* Verify that it's a good sigcontext before using it */
285 if (verify_area(VERIFY_READ, sc, sizeof(*sc)))
287 if (__get_user(set.sig[0], &sc->sc_mask))
290 sigdelsetmask(&set, ~_BLOCKABLE);
291 spin_lock_irq(¤t->sighand->siglock);
292 current->blocked = set;
294 spin_unlock_irq(¤t->sighand->siglock);
296 if (restore_sigcontext(sc, regs, sw))
299 /* Send SIGTRAP if we're single-stepping: */
300 if (ptrace_cancel_bpt (current)) {
303 info.si_signo = SIGTRAP;
305 info.si_code = TRAP_BRKPT;
306 info.si_addr = (void *) regs->pc;
308 send_sig_info(SIGTRAP, &info, current);
313 force_sig(SIGSEGV, current);
317 do_rt_sigreturn(struct rt_sigframe *frame, struct pt_regs *regs,
318 struct switch_stack *sw)
322 /* Verify that it's a good ucontext_t before using it */
323 if (verify_area(VERIFY_READ, &frame->uc, sizeof(frame->uc)))
325 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
328 sigdelsetmask(&set, ~_BLOCKABLE);
329 spin_lock_irq(¤t->sighand->siglock);
330 current->blocked = set;
332 spin_unlock_irq(¤t->sighand->siglock);
334 if (restore_sigcontext(&frame->uc.uc_mcontext, regs, sw))
337 /* Send SIGTRAP if we're single-stepping: */
338 if (ptrace_cancel_bpt (current)) {
341 info.si_signo = SIGTRAP;
343 info.si_code = TRAP_BRKPT;
344 info.si_addr = (void *) regs->pc;
346 send_sig_info(SIGTRAP, &info, current);
351 force_sig(SIGSEGV, current);
356 * Set up a signal frame.
360 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
362 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp))
363 sp = current->sas_ss_sp + current->sas_ss_size;
365 return (void *)((sp - frame_size) & -32ul);
369 setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
370 struct switch_stack *sw, unsigned long mask, unsigned long sp)
374 err |= __put_user(on_sig_stack((unsigned long)sc), &sc->sc_onstack);
375 err |= __put_user(mask, &sc->sc_mask);
376 err |= __put_user(regs->pc, &sc->sc_pc);
377 err |= __put_user(8, &sc->sc_ps);
379 err |= __put_user(regs->r0 , sc->sc_regs+0);
380 err |= __put_user(regs->r1 , sc->sc_regs+1);
381 err |= __put_user(regs->r2 , sc->sc_regs+2);
382 err |= __put_user(regs->r3 , sc->sc_regs+3);
383 err |= __put_user(regs->r4 , sc->sc_regs+4);
384 err |= __put_user(regs->r5 , sc->sc_regs+5);
385 err |= __put_user(regs->r6 , sc->sc_regs+6);
386 err |= __put_user(regs->r7 , sc->sc_regs+7);
387 err |= __put_user(regs->r8 , sc->sc_regs+8);
388 err |= __put_user(sw->r9 , sc->sc_regs+9);
389 err |= __put_user(sw->r10 , sc->sc_regs+10);
390 err |= __put_user(sw->r11 , sc->sc_regs+11);
391 err |= __put_user(sw->r12 , sc->sc_regs+12);
392 err |= __put_user(sw->r13 , sc->sc_regs+13);
393 err |= __put_user(sw->r14 , sc->sc_regs+14);
394 err |= __put_user(sw->r15 , sc->sc_regs+15);
395 err |= __put_user(regs->r16, sc->sc_regs+16);
396 err |= __put_user(regs->r17, sc->sc_regs+17);
397 err |= __put_user(regs->r18, sc->sc_regs+18);
398 err |= __put_user(regs->r19, sc->sc_regs+19);
399 err |= __put_user(regs->r20, sc->sc_regs+20);
400 err |= __put_user(regs->r21, sc->sc_regs+21);
401 err |= __put_user(regs->r22, sc->sc_regs+22);
402 err |= __put_user(regs->r23, sc->sc_regs+23);
403 err |= __put_user(regs->r24, sc->sc_regs+24);
404 err |= __put_user(regs->r25, sc->sc_regs+25);
405 err |= __put_user(regs->r26, sc->sc_regs+26);
406 err |= __put_user(regs->r27, sc->sc_regs+27);
407 err |= __put_user(regs->r28, sc->sc_regs+28);
408 err |= __put_user(regs->gp , sc->sc_regs+29);
409 err |= __put_user(sp, sc->sc_regs+30);
410 err |= __put_user(0, sc->sc_regs+31);
412 for (i = 0; i < 31; i++)
413 err |= __put_user(sw->fp[i], sc->sc_fpregs+i);
414 err |= __put_user(0, sc->sc_fpregs+31);
415 err |= __put_user(sw->fp[31], &sc->sc_fpcr);
417 err |= __put_user(regs->trap_a0, &sc->sc_traparg_a0);
418 err |= __put_user(regs->trap_a1, &sc->sc_traparg_a1);
419 err |= __put_user(regs->trap_a2, &sc->sc_traparg_a2);
425 setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
426 struct pt_regs *regs, struct switch_stack * sw)
428 unsigned long oldsp, r26, err = 0;
429 struct sigframe *frame;
432 frame = get_sigframe(ka, oldsp, sizeof(*frame));
433 if (verify_area(VERIFY_WRITE, frame, sizeof(*frame)))
436 err |= setup_sigcontext(&frame->sc, regs, sw, set->sig[0], oldsp);
440 /* Set up to return from userspace. If provided, use a stub
441 already in userspace. */
442 if (ka->ka_restorer) {
443 r26 = (unsigned long) ka->ka_restorer;
445 err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
446 err |= __put_user(INSN_LDI_R0+__NR_sigreturn, frame->retcode+1);
447 err |= __put_user(INSN_CALLSYS, frame->retcode+2);
449 r26 = (unsigned long) frame->retcode;
452 /* Check that everything was written properly. */
456 /* "Return" to the handler */
458 regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
459 regs->r16 = sig; /* a0: signal number */
460 regs->r17 = 0; /* a1: exception code */
461 regs->r18 = (unsigned long) &frame->sc; /* a2: sigcontext pointer */
462 wrusp((unsigned long) frame);
465 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
466 current->comm, current->pid, frame, regs->pc, regs->r26);
473 ka->sa.sa_handler = SIG_DFL;
474 force_sig(SIGSEGV, current);
478 setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
479 sigset_t *set, struct pt_regs *regs, struct switch_stack * sw)
481 unsigned long oldsp, r26, err = 0;
482 struct rt_sigframe *frame;
485 frame = get_sigframe(ka, oldsp, sizeof(*frame));
486 if (verify_area(VERIFY_WRITE, frame, sizeof(*frame)))
489 err |= copy_siginfo_to_user(&frame->info, info);
491 /* Create the ucontext. */
492 err |= __put_user(0, &frame->uc.uc_flags);
493 err |= __put_user(0, &frame->uc.uc_link);
494 err |= __put_user(set->sig[0], &frame->uc.uc_osf_sigmask);
495 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
496 err |= __put_user(sas_ss_flags(oldsp), &frame->uc.uc_stack.ss_flags);
497 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
498 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, sw,
500 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
504 /* Set up to return from userspace. If provided, use a stub
505 already in userspace. */
506 if (ka->ka_restorer) {
507 r26 = (unsigned long) ka->ka_restorer;
509 err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
510 err |= __put_user(INSN_LDI_R0+__NR_rt_sigreturn,
512 err |= __put_user(INSN_CALLSYS, frame->retcode+2);
514 r26 = (unsigned long) frame->retcode;
520 /* "Return" to the handler */
522 regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
523 regs->r16 = sig; /* a0: signal number */
524 regs->r17 = (unsigned long) &frame->info; /* a1: siginfo pointer */
525 regs->r18 = (unsigned long) &frame->uc; /* a2: ucontext pointer */
526 wrusp((unsigned long) frame);
529 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
530 current->comm, current->pid, frame, regs->pc, regs->r26);
537 ka->sa.sa_handler = SIG_DFL;
538 force_sig(SIGSEGV, current);
543 * OK, we're invoking a handler.
546 handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
547 sigset_t *oldset, struct pt_regs * regs, struct switch_stack *sw)
549 if (ka->sa.sa_flags & SA_SIGINFO)
550 setup_rt_frame(sig, ka, info, oldset, regs, sw);
552 setup_frame(sig, ka, oldset, regs, sw);
554 if (ka->sa.sa_flags & SA_RESETHAND)
555 ka->sa.sa_handler = SIG_DFL;
557 if (!(ka->sa.sa_flags & SA_NODEFER)) {
558 spin_lock_irq(¤t->sighand->siglock);
559 sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
560 sigaddset(¤t->blocked,sig);
562 spin_unlock_irq(¤t->sighand->siglock);
567 syscall_restart(unsigned long r0, unsigned long r19,
568 struct pt_regs *regs, struct k_sigaction *ka)
572 if (!(ka->sa.sa_flags & SA_RESTART)) {
579 regs->r0 = r0; /* reset v0 and a3 and replay syscall */
583 case ERESTART_RESTARTBLOCK:
584 current_thread_info()->restart_block.fn = do_no_restart_syscall;
592 * Note that 'init' is a special process: it doesn't get signals it doesn't
593 * want to handle. Thus you cannot kill init even with a SIGKILL even by
596 * Note that we go through the signals twice: once to check the signals that
597 * the kernel can handle, and then we build all the user-level signal handling
598 * stack-frames in one go after that.
600 * "r0" and "r19" are the registers we need to restore for system call
601 * restart. "r0" is also used as an indicator whether we can restart at
602 * all (if we get here from anything but a syscall return, it will be 0)
605 do_signal(sigset_t *oldset, struct pt_regs * regs, struct switch_stack * sw,
606 unsigned long r0, unsigned long r19)
610 unsigned long single_stepping = ptrace_cancel_bpt(current);
613 oldset = ¤t->blocked;
615 /* This lets the debugger run, ... */
616 signr = get_signal_to_deliver(&info, regs, NULL);
617 /* ... so re-check the single stepping. */
618 single_stepping |= ptrace_cancel_bpt(current);
621 /* Whee! Actually deliver the signal. */
622 struct k_sigaction *ka = ¤t->sighand->action[signr-1];
624 if (r0) syscall_restart(r0, r19, regs, ka);
625 handle_signal(signr, ka, &info, oldset, regs, sw);
627 ptrace_set_bpt(current); /* re-set bpt */
636 /* Reset v0 and a3 and replay syscall. */
641 case ERESTART_RESTARTBLOCK:
642 /* Force v0 to the restart syscall and reply. */
643 regs->r0 = __NR_restart_syscall;
649 ptrace_set_bpt(current); /* re-set breakpoint */
655 do_notify_resume(sigset_t *oldset, struct pt_regs *regs,
656 struct switch_stack *sw, unsigned long r0,
657 unsigned long r19, unsigned long thread_info_flags)
659 if (thread_info_flags & _TIF_SIGPENDING)
660 do_signal(oldset, regs, sw, r0, r19);