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/stddef.h>
19 #include <linux/tty.h>
20 #include <linux/binfmts.h>
21 #include <linux/bitops.h>
22 #include <linux/syscalls.h>
23 #include <linux/tracehook.h>
25 #include <asm/uaccess.h>
26 #include <asm/sigcontext.h>
27 #include <asm/ucontext.h>
34 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
36 asmlinkage void ret_from_sys_call(void);
39 * The OSF/1 sigprocmask calling sequence is different from the
40 * C sigprocmask() sequence..
42 SYSCALL_DEFINE2(osf_sigprocmask, int, how, unsigned long, newmask)
48 siginitset(&mask, newmask & _BLOCKABLE);
49 res = sigprocmask(how, &mask, &oldmask);
51 force_successful_syscall_return();
57 SYSCALL_DEFINE3(osf_sigaction, int, sig,
58 const struct osf_sigaction __user *, act,
59 struct osf_sigaction __user *, oact)
61 struct k_sigaction new_ka, old_ka;
66 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
67 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
68 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
69 __get_user(mask, &act->sa_mask))
71 siginitset(&new_ka.sa.sa_mask, mask);
72 new_ka.ka_restorer = NULL;
75 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
78 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
79 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
80 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
81 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
88 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
89 struct sigaction __user *, oact,
90 size_t, sigsetsize, void __user *, restorer)
92 struct k_sigaction new_ka, old_ka;
95 /* XXX: Don't preclude handling different sized sigset_t's. */
96 if (sigsetsize != sizeof(sigset_t))
100 new_ka.ka_restorer = restorer;
101 if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
105 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
108 if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
116 * Atomically swap in the new signal mask, and wait for a signal.
118 SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask)
121 siginitset(&blocked, mask);
122 return sigsuspend(&blocked);
126 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
128 return do_sigaltstack(uss, uoss, rdusp());
132 * Do a signal return; undo the signal stack.
136 # error "Non SA_SIGINFO frame needs rearranging"
141 struct sigcontext sc;
142 unsigned int retcode[3];
149 unsigned int retcode[3];
152 /* If this changes, userland unwinders that Know Things about our signal
153 frame will break. Do not undertake lightly. It also implies an ABI
154 change wrt the size of siginfo_t, which may cause some pain. */
155 extern char compile_time_assert
156 [offsetof(struct rt_sigframe, uc.uc_mcontext) == 176 ? 1 : -1];
158 #define INSN_MOV_R30_R16 0x47fe0410
159 #define INSN_LDI_R0 0x201f0000
160 #define INSN_CALLSYS 0x00000083
163 restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
164 struct switch_stack *sw)
167 long i, err = __get_user(regs->pc, &sc->sc_pc);
169 current_thread_info()->restart_block.fn = do_no_restart_syscall;
171 sw->r26 = (unsigned long) ret_from_sys_call;
173 err |= __get_user(regs->r0, sc->sc_regs+0);
174 err |= __get_user(regs->r1, sc->sc_regs+1);
175 err |= __get_user(regs->r2, sc->sc_regs+2);
176 err |= __get_user(regs->r3, sc->sc_regs+3);
177 err |= __get_user(regs->r4, sc->sc_regs+4);
178 err |= __get_user(regs->r5, sc->sc_regs+5);
179 err |= __get_user(regs->r6, sc->sc_regs+6);
180 err |= __get_user(regs->r7, sc->sc_regs+7);
181 err |= __get_user(regs->r8, sc->sc_regs+8);
182 err |= __get_user(sw->r9, sc->sc_regs+9);
183 err |= __get_user(sw->r10, sc->sc_regs+10);
184 err |= __get_user(sw->r11, sc->sc_regs+11);
185 err |= __get_user(sw->r12, sc->sc_regs+12);
186 err |= __get_user(sw->r13, sc->sc_regs+13);
187 err |= __get_user(sw->r14, sc->sc_regs+14);
188 err |= __get_user(sw->r15, sc->sc_regs+15);
189 err |= __get_user(regs->r16, sc->sc_regs+16);
190 err |= __get_user(regs->r17, sc->sc_regs+17);
191 err |= __get_user(regs->r18, sc->sc_regs+18);
192 err |= __get_user(regs->r19, sc->sc_regs+19);
193 err |= __get_user(regs->r20, sc->sc_regs+20);
194 err |= __get_user(regs->r21, sc->sc_regs+21);
195 err |= __get_user(regs->r22, sc->sc_regs+22);
196 err |= __get_user(regs->r23, sc->sc_regs+23);
197 err |= __get_user(regs->r24, sc->sc_regs+24);
198 err |= __get_user(regs->r25, sc->sc_regs+25);
199 err |= __get_user(regs->r26, sc->sc_regs+26);
200 err |= __get_user(regs->r27, sc->sc_regs+27);
201 err |= __get_user(regs->r28, sc->sc_regs+28);
202 err |= __get_user(regs->gp, sc->sc_regs+29);
203 err |= __get_user(usp, sc->sc_regs+30);
206 for (i = 0; i < 31; i++)
207 err |= __get_user(sw->fp[i], sc->sc_fpregs+i);
208 err |= __get_user(sw->fp[31], &sc->sc_fpcr);
213 /* Note that this syscall is also used by setcontext(3) to install
214 a given sigcontext. This because it's impossible to set *all*
215 registers and transfer control from userland. */
218 do_sigreturn(struct sigcontext __user *sc, struct pt_regs *regs,
219 struct switch_stack *sw)
223 /* Verify that it's a good sigcontext before using it */
224 if (!access_ok(VERIFY_READ, sc, sizeof(*sc)))
226 if (__get_user(set.sig[0], &sc->sc_mask))
229 sigdelsetmask(&set, ~_BLOCKABLE);
230 set_current_blocked(&set);
232 if (restore_sigcontext(sc, regs, sw))
235 /* Send SIGTRAP if we're single-stepping: */
236 if (ptrace_cancel_bpt (current)) {
239 info.si_signo = SIGTRAP;
241 info.si_code = TRAP_BRKPT;
242 info.si_addr = (void __user *) regs->pc;
244 send_sig_info(SIGTRAP, &info, current);
249 force_sig(SIGSEGV, current);
253 do_rt_sigreturn(struct rt_sigframe __user *frame, struct pt_regs *regs,
254 struct switch_stack *sw)
258 /* Verify that it's a good ucontext_t before using it */
259 if (!access_ok(VERIFY_READ, &frame->uc, sizeof(frame->uc)))
261 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
264 sigdelsetmask(&set, ~_BLOCKABLE);
265 set_current_blocked(&set);
267 if (restore_sigcontext(&frame->uc.uc_mcontext, regs, sw))
270 /* Send SIGTRAP if we're single-stepping: */
271 if (ptrace_cancel_bpt (current)) {
274 info.si_signo = SIGTRAP;
276 info.si_code = TRAP_BRKPT;
277 info.si_addr = (void __user *) regs->pc;
279 send_sig_info(SIGTRAP, &info, current);
284 force_sig(SIGSEGV, current);
289 * Set up a signal frame.
292 static inline void __user *
293 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
295 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
296 sp = current->sas_ss_sp + current->sas_ss_size;
298 return (void __user *)((sp - frame_size) & -32ul);
302 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
303 struct switch_stack *sw, unsigned long mask, unsigned long sp)
307 err |= __put_user(on_sig_stack((unsigned long)sc), &sc->sc_onstack);
308 err |= __put_user(mask, &sc->sc_mask);
309 err |= __put_user(regs->pc, &sc->sc_pc);
310 err |= __put_user(8, &sc->sc_ps);
312 err |= __put_user(regs->r0 , sc->sc_regs+0);
313 err |= __put_user(regs->r1 , sc->sc_regs+1);
314 err |= __put_user(regs->r2 , sc->sc_regs+2);
315 err |= __put_user(regs->r3 , sc->sc_regs+3);
316 err |= __put_user(regs->r4 , sc->sc_regs+4);
317 err |= __put_user(regs->r5 , sc->sc_regs+5);
318 err |= __put_user(regs->r6 , sc->sc_regs+6);
319 err |= __put_user(regs->r7 , sc->sc_regs+7);
320 err |= __put_user(regs->r8 , sc->sc_regs+8);
321 err |= __put_user(sw->r9 , sc->sc_regs+9);
322 err |= __put_user(sw->r10 , sc->sc_regs+10);
323 err |= __put_user(sw->r11 , sc->sc_regs+11);
324 err |= __put_user(sw->r12 , sc->sc_regs+12);
325 err |= __put_user(sw->r13 , sc->sc_regs+13);
326 err |= __put_user(sw->r14 , sc->sc_regs+14);
327 err |= __put_user(sw->r15 , sc->sc_regs+15);
328 err |= __put_user(regs->r16, sc->sc_regs+16);
329 err |= __put_user(regs->r17, sc->sc_regs+17);
330 err |= __put_user(regs->r18, sc->sc_regs+18);
331 err |= __put_user(regs->r19, sc->sc_regs+19);
332 err |= __put_user(regs->r20, sc->sc_regs+20);
333 err |= __put_user(regs->r21, sc->sc_regs+21);
334 err |= __put_user(regs->r22, sc->sc_regs+22);
335 err |= __put_user(regs->r23, sc->sc_regs+23);
336 err |= __put_user(regs->r24, sc->sc_regs+24);
337 err |= __put_user(regs->r25, sc->sc_regs+25);
338 err |= __put_user(regs->r26, sc->sc_regs+26);
339 err |= __put_user(regs->r27, sc->sc_regs+27);
340 err |= __put_user(regs->r28, sc->sc_regs+28);
341 err |= __put_user(regs->gp , sc->sc_regs+29);
342 err |= __put_user(sp, sc->sc_regs+30);
343 err |= __put_user(0, sc->sc_regs+31);
345 for (i = 0; i < 31; i++)
346 err |= __put_user(sw->fp[i], sc->sc_fpregs+i);
347 err |= __put_user(0, sc->sc_fpregs+31);
348 err |= __put_user(sw->fp[31], &sc->sc_fpcr);
350 err |= __put_user(regs->trap_a0, &sc->sc_traparg_a0);
351 err |= __put_user(regs->trap_a1, &sc->sc_traparg_a1);
352 err |= __put_user(regs->trap_a2, &sc->sc_traparg_a2);
358 setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
359 struct pt_regs *regs, struct switch_stack * sw)
361 unsigned long oldsp, r26, err = 0;
362 struct sigframe __user *frame;
365 frame = get_sigframe(ka, oldsp, sizeof(*frame));
366 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
369 err |= setup_sigcontext(&frame->sc, regs, sw, set->sig[0], oldsp);
373 /* Set up to return from userspace. If provided, use a stub
374 already in userspace. */
375 if (ka->ka_restorer) {
376 r26 = (unsigned long) ka->ka_restorer;
378 err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
379 err |= __put_user(INSN_LDI_R0+__NR_sigreturn, frame->retcode+1);
380 err |= __put_user(INSN_CALLSYS, frame->retcode+2);
382 r26 = (unsigned long) frame->retcode;
385 /* Check that everything was written properly. */
389 /* "Return" to the handler */
391 regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
392 regs->r16 = sig; /* a0: signal number */
393 regs->r17 = 0; /* a1: exception code */
394 regs->r18 = (unsigned long) &frame->sc; /* a2: sigcontext pointer */
395 wrusp((unsigned long) frame);
398 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
399 current->comm, current->pid, frame, regs->pc, regs->r26);
405 setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
406 sigset_t *set, struct pt_regs *regs, struct switch_stack * sw)
408 unsigned long oldsp, r26, err = 0;
409 struct rt_sigframe __user *frame;
412 frame = get_sigframe(ka, oldsp, sizeof(*frame));
413 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
416 err |= copy_siginfo_to_user(&frame->info, info);
418 /* Create the ucontext. */
419 err |= __put_user(0, &frame->uc.uc_flags);
420 err |= __put_user(0, &frame->uc.uc_link);
421 err |= __put_user(set->sig[0], &frame->uc.uc_osf_sigmask);
422 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
423 err |= __put_user(sas_ss_flags(oldsp), &frame->uc.uc_stack.ss_flags);
424 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
425 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, sw,
427 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
431 /* Set up to return from userspace. If provided, use a stub
432 already in userspace. */
433 if (ka->ka_restorer) {
434 r26 = (unsigned long) ka->ka_restorer;
436 err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
437 err |= __put_user(INSN_LDI_R0+__NR_rt_sigreturn,
439 err |= __put_user(INSN_CALLSYS, frame->retcode+2);
441 r26 = (unsigned long) frame->retcode;
447 /* "Return" to the handler */
449 regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
450 regs->r16 = sig; /* a0: signal number */
451 regs->r17 = (unsigned long) &frame->info; /* a1: siginfo pointer */
452 regs->r18 = (unsigned long) &frame->uc; /* a2: ucontext pointer */
453 wrusp((unsigned long) frame);
456 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
457 current->comm, current->pid, frame, regs->pc, regs->r26);
465 * OK, we're invoking a handler.
468 handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
469 struct pt_regs * regs, struct switch_stack *sw)
471 sigset_t *oldset = sigmask_to_save();
474 if (ka->sa.sa_flags & SA_SIGINFO)
475 ret = setup_rt_frame(sig, ka, info, oldset, regs, sw);
477 ret = setup_frame(sig, ka, oldset, regs, sw);
480 force_sigsegv(sig, current);
483 block_sigmask(ka, sig);
487 syscall_restart(unsigned long r0, unsigned long r19,
488 struct pt_regs *regs, struct k_sigaction *ka)
492 if (!(ka->sa.sa_flags & SA_RESTART)) {
499 regs->r0 = r0; /* reset v0 and a3 and replay syscall */
503 case ERESTART_RESTARTBLOCK:
511 * Note that 'init' is a special process: it doesn't get signals it doesn't
512 * want to handle. Thus you cannot kill init even with a SIGKILL even by
515 * Note that we go through the signals twice: once to check the signals that
516 * the kernel can handle, and then we build all the user-level signal handling
517 * stack-frames in one go after that.
519 * "r0" and "r19" are the registers we need to restore for system call
520 * restart. "r0" is also used as an indicator whether we can restart at
521 * all (if we get here from anything but a syscall return, it will be 0)
524 do_signal(struct pt_regs * regs, struct switch_stack * sw,
525 unsigned long r0, unsigned long r19)
529 unsigned long single_stepping = ptrace_cancel_bpt(current);
530 struct k_sigaction ka;
532 /* This lets the debugger run, ... */
533 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
535 /* ... so re-check the single stepping. */
536 single_stepping |= ptrace_cancel_bpt(current);
539 /* Whee! Actually deliver the signal. */
541 syscall_restart(r0, r19, regs, &ka);
542 handle_signal(signr, &ka, &info, regs, sw);
544 ptrace_set_bpt(current); /* re-set bpt */
553 /* Reset v0 and a3 and replay syscall. */
558 case ERESTART_RESTARTBLOCK:
559 /* Force v0 to the restart syscall and reply. */
560 regs->r0 = __NR_restart_syscall;
566 /* If there's no signal to deliver, we just restore the saved mask. */
567 restore_saved_sigmask();
569 ptrace_set_bpt(current); /* re-set breakpoint */
573 do_notify_resume(struct pt_regs *regs, struct switch_stack *sw,
574 unsigned long thread_info_flags,
575 unsigned long r0, unsigned long r19)
577 if (thread_info_flags & _TIF_SIGPENDING)
578 do_signal(regs, sw, r0, r19);
580 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
581 clear_thread_flag(TIF_NOTIFY_RESUME);
582 tracehook_notify_resume(regs);