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);
37 static void do_signal(struct pt_regs
*, struct switch_stack
*,
38 unsigned long, unsigned long);
42 * The OSF/1 sigprocmask calling sequence is different from the
43 * C sigprocmask() sequence..
50 * We change the range to -1 .. 1 in order to let gcc easily
51 * use the conditional move instructions.
53 * Note that we don't need to acquire the kernel lock for SMP
54 * operation, as all of this is local to this thread.
56 SYSCALL_DEFINE3(osf_sigprocmask
, int, how
, unsigned long, newmask
,
57 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 regs
->r0
= 0; /* special no error return */
86 SYSCALL_DEFINE3(osf_sigaction
, int, sig
,
87 const struct osf_sigaction __user
*, act
,
88 struct osf_sigaction __user
*, oact
)
90 struct k_sigaction new_ka
, old_ka
;
95 if (!access_ok(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 (!access_ok(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
);
117 SYSCALL_DEFINE5(rt_sigaction
, int, sig
, const struct sigaction __user
*, act
,
118 struct sigaction __user
*, oact
,
119 size_t, sigsetsize
, void __user
*, 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
*regs
, struct switch_stack
*sw
)
151 spin_lock_irq(¤t
->sighand
->siglock
);
152 current
->saved_sigmask
= current
->blocked
;
153 siginitset(¤t
->blocked
, mask
);
155 spin_unlock_irq(¤t
->sighand
->siglock
);
157 /* Indicate EINTR on return from any possible signal handler,
158 which will not come back through here, but via sigreturn. */
162 current
->state
= TASK_INTERRUPTIBLE
;
164 set_thread_flag(TIF_RESTORE_SIGMASK
);
165 return -ERESTARTNOHAND
;
169 do_rt_sigsuspend(sigset_t __user
*uset
, size_t sigsetsize
,
170 struct pt_regs
*regs
, struct switch_stack
*sw
)
174 /* XXX: Don't preclude handling different sized sigset_t's. */
175 if (sigsetsize
!= sizeof(sigset_t
))
177 if (copy_from_user(&set
, uset
, sizeof(set
)))
180 sigdelsetmask(&set
, ~_BLOCKABLE
);
181 spin_lock_irq(¤t
->sighand
->siglock
);
182 current
->saved_sigmask
= current
->blocked
;
183 current
->blocked
= set
;
185 spin_unlock_irq(¤t
->sighand
->siglock
);
187 /* Indicate EINTR on return from any possible signal handler,
188 which will not come back through here, but via sigreturn. */
192 current
->state
= TASK_INTERRUPTIBLE
;
194 set_thread_flag(TIF_RESTORE_SIGMASK
);
195 return -ERESTARTNOHAND
;
199 sys_sigaltstack(const stack_t __user
*uss
, stack_t __user
*uoss
)
201 return do_sigaltstack(uss
, uoss
, rdusp());
205 * Do a signal return; undo the signal stack.
209 # error "Non SA_SIGINFO frame needs rearranging"
214 struct sigcontext sc
;
215 unsigned int retcode
[3];
222 unsigned int retcode
[3];
225 /* If this changes, userland unwinders that Know Things about our signal
226 frame will break. Do not undertake lightly. It also implies an ABI
227 change wrt the size of siginfo_t, which may cause some pain. */
228 extern char compile_time_assert
229 [offsetof(struct rt_sigframe
, uc
.uc_mcontext
) == 176 ? 1 : -1];
231 #define INSN_MOV_R30_R16 0x47fe0410
232 #define INSN_LDI_R0 0x201f0000
233 #define INSN_CALLSYS 0x00000083
236 restore_sigcontext(struct sigcontext __user
*sc
, struct pt_regs
*regs
,
237 struct switch_stack
*sw
)
240 long i
, err
= __get_user(regs
->pc
, &sc
->sc_pc
);
242 sw
->r26
= (unsigned long) ret_from_sys_call
;
244 err
|= __get_user(regs
->r0
, sc
->sc_regs
+0);
245 err
|= __get_user(regs
->r1
, sc
->sc_regs
+1);
246 err
|= __get_user(regs
->r2
, sc
->sc_regs
+2);
247 err
|= __get_user(regs
->r3
, sc
->sc_regs
+3);
248 err
|= __get_user(regs
->r4
, sc
->sc_regs
+4);
249 err
|= __get_user(regs
->r5
, sc
->sc_regs
+5);
250 err
|= __get_user(regs
->r6
, sc
->sc_regs
+6);
251 err
|= __get_user(regs
->r7
, sc
->sc_regs
+7);
252 err
|= __get_user(regs
->r8
, sc
->sc_regs
+8);
253 err
|= __get_user(sw
->r9
, sc
->sc_regs
+9);
254 err
|= __get_user(sw
->r10
, sc
->sc_regs
+10);
255 err
|= __get_user(sw
->r11
, sc
->sc_regs
+11);
256 err
|= __get_user(sw
->r12
, sc
->sc_regs
+12);
257 err
|= __get_user(sw
->r13
, sc
->sc_regs
+13);
258 err
|= __get_user(sw
->r14
, sc
->sc_regs
+14);
259 err
|= __get_user(sw
->r15
, sc
->sc_regs
+15);
260 err
|= __get_user(regs
->r16
, sc
->sc_regs
+16);
261 err
|= __get_user(regs
->r17
, sc
->sc_regs
+17);
262 err
|= __get_user(regs
->r18
, sc
->sc_regs
+18);
263 err
|= __get_user(regs
->r19
, sc
->sc_regs
+19);
264 err
|= __get_user(regs
->r20
, sc
->sc_regs
+20);
265 err
|= __get_user(regs
->r21
, sc
->sc_regs
+21);
266 err
|= __get_user(regs
->r22
, sc
->sc_regs
+22);
267 err
|= __get_user(regs
->r23
, sc
->sc_regs
+23);
268 err
|= __get_user(regs
->r24
, sc
->sc_regs
+24);
269 err
|= __get_user(regs
->r25
, sc
->sc_regs
+25);
270 err
|= __get_user(regs
->r26
, sc
->sc_regs
+26);
271 err
|= __get_user(regs
->r27
, sc
->sc_regs
+27);
272 err
|= __get_user(regs
->r28
, sc
->sc_regs
+28);
273 err
|= __get_user(regs
->gp
, sc
->sc_regs
+29);
274 err
|= __get_user(usp
, sc
->sc_regs
+30);
277 for (i
= 0; i
< 31; i
++)
278 err
|= __get_user(sw
->fp
[i
], sc
->sc_fpregs
+i
);
279 err
|= __get_user(sw
->fp
[31], &sc
->sc_fpcr
);
284 /* Note that this syscall is also used by setcontext(3) to install
285 a given sigcontext. This because it's impossible to set *all*
286 registers and transfer control from userland. */
289 do_sigreturn(struct sigcontext __user
*sc
, struct pt_regs
*regs
,
290 struct switch_stack
*sw
)
294 /* Verify that it's a good sigcontext before using it */
295 if (!access_ok(VERIFY_READ
, sc
, sizeof(*sc
)))
297 if (__get_user(set
.sig
[0], &sc
->sc_mask
))
300 sigdelsetmask(&set
, ~_BLOCKABLE
);
301 spin_lock_irq(¤t
->sighand
->siglock
);
302 current
->blocked
= set
;
304 spin_unlock_irq(¤t
->sighand
->siglock
);
306 if (restore_sigcontext(sc
, regs
, sw
))
309 /* Send SIGTRAP if we're single-stepping: */
310 if (ptrace_cancel_bpt (current
)) {
313 info
.si_signo
= SIGTRAP
;
315 info
.si_code
= TRAP_BRKPT
;
316 info
.si_addr
= (void __user
*) regs
->pc
;
318 send_sig_info(SIGTRAP
, &info
, current
);
323 force_sig(SIGSEGV
, current
);
327 do_rt_sigreturn(struct rt_sigframe __user
*frame
, struct pt_regs
*regs
,
328 struct switch_stack
*sw
)
332 /* Verify that it's a good ucontext_t before using it */
333 if (!access_ok(VERIFY_READ
, &frame
->uc
, sizeof(frame
->uc
)))
335 if (__copy_from_user(&set
, &frame
->uc
.uc_sigmask
, sizeof(set
)))
338 sigdelsetmask(&set
, ~_BLOCKABLE
);
339 spin_lock_irq(¤t
->sighand
->siglock
);
340 current
->blocked
= set
;
342 spin_unlock_irq(¤t
->sighand
->siglock
);
344 if (restore_sigcontext(&frame
->uc
.uc_mcontext
, regs
, sw
))
347 /* Send SIGTRAP if we're single-stepping: */
348 if (ptrace_cancel_bpt (current
)) {
351 info
.si_signo
= SIGTRAP
;
353 info
.si_code
= TRAP_BRKPT
;
354 info
.si_addr
= (void __user
*) regs
->pc
;
356 send_sig_info(SIGTRAP
, &info
, current
);
361 force_sig(SIGSEGV
, current
);
366 * Set up a signal frame.
369 static inline void __user
*
370 get_sigframe(struct k_sigaction
*ka
, unsigned long sp
, size_t frame_size
)
372 if ((ka
->sa
.sa_flags
& SA_ONSTACK
) != 0 && ! sas_ss_flags(sp
))
373 sp
= current
->sas_ss_sp
+ current
->sas_ss_size
;
375 return (void __user
*)((sp
- frame_size
) & -32ul);
379 setup_sigcontext(struct sigcontext __user
*sc
, struct pt_regs
*regs
,
380 struct switch_stack
*sw
, unsigned long mask
, unsigned long sp
)
384 err
|= __put_user(on_sig_stack((unsigned long)sc
), &sc
->sc_onstack
);
385 err
|= __put_user(mask
, &sc
->sc_mask
);
386 err
|= __put_user(regs
->pc
, &sc
->sc_pc
);
387 err
|= __put_user(8, &sc
->sc_ps
);
389 err
|= __put_user(regs
->r0
, sc
->sc_regs
+0);
390 err
|= __put_user(regs
->r1
, sc
->sc_regs
+1);
391 err
|= __put_user(regs
->r2
, sc
->sc_regs
+2);
392 err
|= __put_user(regs
->r3
, sc
->sc_regs
+3);
393 err
|= __put_user(regs
->r4
, sc
->sc_regs
+4);
394 err
|= __put_user(regs
->r5
, sc
->sc_regs
+5);
395 err
|= __put_user(regs
->r6
, sc
->sc_regs
+6);
396 err
|= __put_user(regs
->r7
, sc
->sc_regs
+7);
397 err
|= __put_user(regs
->r8
, sc
->sc_regs
+8);
398 err
|= __put_user(sw
->r9
, sc
->sc_regs
+9);
399 err
|= __put_user(sw
->r10
, sc
->sc_regs
+10);
400 err
|= __put_user(sw
->r11
, sc
->sc_regs
+11);
401 err
|= __put_user(sw
->r12
, sc
->sc_regs
+12);
402 err
|= __put_user(sw
->r13
, sc
->sc_regs
+13);
403 err
|= __put_user(sw
->r14
, sc
->sc_regs
+14);
404 err
|= __put_user(sw
->r15
, sc
->sc_regs
+15);
405 err
|= __put_user(regs
->r16
, sc
->sc_regs
+16);
406 err
|= __put_user(regs
->r17
, sc
->sc_regs
+17);
407 err
|= __put_user(regs
->r18
, sc
->sc_regs
+18);
408 err
|= __put_user(regs
->r19
, sc
->sc_regs
+19);
409 err
|= __put_user(regs
->r20
, sc
->sc_regs
+20);
410 err
|= __put_user(regs
->r21
, sc
->sc_regs
+21);
411 err
|= __put_user(regs
->r22
, sc
->sc_regs
+22);
412 err
|= __put_user(regs
->r23
, sc
->sc_regs
+23);
413 err
|= __put_user(regs
->r24
, sc
->sc_regs
+24);
414 err
|= __put_user(regs
->r25
, sc
->sc_regs
+25);
415 err
|= __put_user(regs
->r26
, sc
->sc_regs
+26);
416 err
|= __put_user(regs
->r27
, sc
->sc_regs
+27);
417 err
|= __put_user(regs
->r28
, sc
->sc_regs
+28);
418 err
|= __put_user(regs
->gp
, sc
->sc_regs
+29);
419 err
|= __put_user(sp
, sc
->sc_regs
+30);
420 err
|= __put_user(0, sc
->sc_regs
+31);
422 for (i
= 0; i
< 31; i
++)
423 err
|= __put_user(sw
->fp
[i
], sc
->sc_fpregs
+i
);
424 err
|= __put_user(0, sc
->sc_fpregs
+31);
425 err
|= __put_user(sw
->fp
[31], &sc
->sc_fpcr
);
427 err
|= __put_user(regs
->trap_a0
, &sc
->sc_traparg_a0
);
428 err
|= __put_user(regs
->trap_a1
, &sc
->sc_traparg_a1
);
429 err
|= __put_user(regs
->trap_a2
, &sc
->sc_traparg_a2
);
435 setup_frame(int sig
, struct k_sigaction
*ka
, sigset_t
*set
,
436 struct pt_regs
*regs
, struct switch_stack
* sw
)
438 unsigned long oldsp
, r26
, err
= 0;
439 struct sigframe __user
*frame
;
442 frame
= get_sigframe(ka
, oldsp
, sizeof(*frame
));
443 if (!access_ok(VERIFY_WRITE
, frame
, sizeof(*frame
)))
446 err
|= setup_sigcontext(&frame
->sc
, regs
, sw
, set
->sig
[0], oldsp
);
450 /* Set up to return from userspace. If provided, use a stub
451 already in userspace. */
452 if (ka
->ka_restorer
) {
453 r26
= (unsigned long) ka
->ka_restorer
;
455 err
|= __put_user(INSN_MOV_R30_R16
, frame
->retcode
+0);
456 err
|= __put_user(INSN_LDI_R0
+__NR_sigreturn
, frame
->retcode
+1);
457 err
|= __put_user(INSN_CALLSYS
, frame
->retcode
+2);
459 r26
= (unsigned long) frame
->retcode
;
462 /* Check that everything was written properly. */
466 /* "Return" to the handler */
468 regs
->r27
= regs
->pc
= (unsigned long) ka
->sa
.sa_handler
;
469 regs
->r16
= sig
; /* a0: signal number */
470 regs
->r17
= 0; /* a1: exception code */
471 regs
->r18
= (unsigned long) &frame
->sc
; /* a2: sigcontext pointer */
472 wrusp((unsigned long) frame
);
475 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
476 current
->comm
, current
->pid
, frame
, regs
->pc
, regs
->r26
);
482 force_sigsegv(sig
, current
);
487 setup_rt_frame(int sig
, struct k_sigaction
*ka
, siginfo_t
*info
,
488 sigset_t
*set
, struct pt_regs
*regs
, struct switch_stack
* sw
)
490 unsigned long oldsp
, r26
, err
= 0;
491 struct rt_sigframe __user
*frame
;
494 frame
= get_sigframe(ka
, oldsp
, sizeof(*frame
));
495 if (!access_ok(VERIFY_WRITE
, frame
, sizeof(*frame
)))
498 err
|= copy_siginfo_to_user(&frame
->info
, info
);
500 /* Create the ucontext. */
501 err
|= __put_user(0, &frame
->uc
.uc_flags
);
502 err
|= __put_user(0, &frame
->uc
.uc_link
);
503 err
|= __put_user(set
->sig
[0], &frame
->uc
.uc_osf_sigmask
);
504 err
|= __put_user(current
->sas_ss_sp
, &frame
->uc
.uc_stack
.ss_sp
);
505 err
|= __put_user(sas_ss_flags(oldsp
), &frame
->uc
.uc_stack
.ss_flags
);
506 err
|= __put_user(current
->sas_ss_size
, &frame
->uc
.uc_stack
.ss_size
);
507 err
|= setup_sigcontext(&frame
->uc
.uc_mcontext
, regs
, sw
,
509 err
|= __copy_to_user(&frame
->uc
.uc_sigmask
, set
, sizeof(*set
));
513 /* Set up to return from userspace. If provided, use a stub
514 already in userspace. */
515 if (ka
->ka_restorer
) {
516 r26
= (unsigned long) ka
->ka_restorer
;
518 err
|= __put_user(INSN_MOV_R30_R16
, frame
->retcode
+0);
519 err
|= __put_user(INSN_LDI_R0
+__NR_rt_sigreturn
,
521 err
|= __put_user(INSN_CALLSYS
, frame
->retcode
+2);
523 r26
= (unsigned long) frame
->retcode
;
529 /* "Return" to the handler */
531 regs
->r27
= regs
->pc
= (unsigned long) ka
->sa
.sa_handler
;
532 regs
->r16
= sig
; /* a0: signal number */
533 regs
->r17
= (unsigned long) &frame
->info
; /* a1: siginfo pointer */
534 regs
->r18
= (unsigned long) &frame
->uc
; /* a2: ucontext pointer */
535 wrusp((unsigned long) frame
);
538 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
539 current
->comm
, current
->pid
, frame
, regs
->pc
, regs
->r26
);
545 force_sigsegv(sig
, current
);
551 * OK, we're invoking a handler.
554 handle_signal(int sig
, struct k_sigaction
*ka
, siginfo_t
*info
,
555 sigset_t
*oldset
, struct pt_regs
* regs
, struct switch_stack
*sw
)
559 if (ka
->sa
.sa_flags
& SA_SIGINFO
)
560 ret
= setup_rt_frame(sig
, ka
, info
, oldset
, regs
, sw
);
562 ret
= setup_frame(sig
, ka
, oldset
, regs
, sw
);
565 spin_lock_irq(¤t
->sighand
->siglock
);
566 sigorsets(¤t
->blocked
,¤t
->blocked
,&ka
->sa
.sa_mask
);
567 if (!(ka
->sa
.sa_flags
& SA_NODEFER
))
568 sigaddset(¤t
->blocked
,sig
);
570 spin_unlock_irq(¤t
->sighand
->siglock
);
577 syscall_restart(unsigned long r0
, unsigned long r19
,
578 struct pt_regs
*regs
, struct k_sigaction
*ka
)
582 if (!(ka
->sa
.sa_flags
& SA_RESTART
)) {
589 regs
->r0
= r0
; /* reset v0 and a3 and replay syscall */
593 case ERESTART_RESTARTBLOCK
:
594 current_thread_info()->restart_block
.fn
= do_no_restart_syscall
;
602 * Note that 'init' is a special process: it doesn't get signals it doesn't
603 * want to handle. Thus you cannot kill init even with a SIGKILL even by
606 * Note that we go through the signals twice: once to check the signals that
607 * the kernel can handle, and then we build all the user-level signal handling
608 * stack-frames in one go after that.
610 * "r0" and "r19" are the registers we need to restore for system call
611 * restart. "r0" is also used as an indicator whether we can restart at
612 * all (if we get here from anything but a syscall return, it will be 0)
615 do_signal(struct pt_regs
* regs
, struct switch_stack
* sw
,
616 unsigned long r0
, unsigned long r19
)
620 unsigned long single_stepping
= ptrace_cancel_bpt(current
);
621 struct k_sigaction ka
;
624 if (test_thread_flag(TIF_RESTORE_SIGMASK
))
625 oldset
= ¤t
->saved_sigmask
;
627 oldset
= ¤t
->blocked
;
629 /* This lets the debugger run, ... */
630 signr
= get_signal_to_deliver(&info
, &ka
, regs
, NULL
);
632 /* ... so re-check the single stepping. */
633 single_stepping
|= ptrace_cancel_bpt(current
);
636 /* Whee! Actually deliver the signal. */
638 syscall_restart(r0
, r19
, regs
, &ka
);
639 if (handle_signal(signr
, &ka
, &info
, oldset
, regs
, sw
) == 0) {
640 /* A signal was successfully delivered, and the
641 saved sigmask was stored on the signal frame,
642 and will be restored by sigreturn. So we can
643 simply clear the restore sigmask flag. */
644 if (test_thread_flag(TIF_RESTORE_SIGMASK
))
645 clear_thread_flag(TIF_RESTORE_SIGMASK
);
648 ptrace_set_bpt(current
); /* re-set bpt */
657 /* Reset v0 and a3 and replay syscall. */
662 case ERESTART_RESTARTBLOCK
:
663 /* Force v0 to the restart syscall and reply. */
664 regs
->r0
= __NR_restart_syscall
;
670 /* If there's no signal to deliver, we just restore the saved mask. */
671 if (test_thread_flag(TIF_RESTORE_SIGMASK
)) {
672 clear_thread_flag(TIF_RESTORE_SIGMASK
);
673 sigprocmask(SIG_SETMASK
, ¤t
->saved_sigmask
, NULL
);
677 ptrace_set_bpt(current
); /* re-set breakpoint */
681 do_notify_resume(struct pt_regs
*regs
, struct switch_stack
*sw
,
682 unsigned long thread_info_flags
,
683 unsigned long r0
, unsigned long r19
)
685 if (thread_info_flags
& (_TIF_SIGPENDING
| _TIF_RESTORE_SIGMASK
))
686 do_signal(regs
, sw
, r0
, r19
);
688 if (thread_info_flags
& _TIF_NOTIFY_RESUME
) {
689 clear_thread_flag(TIF_NOTIFY_RESUME
);
690 tracehook_notify_resume(regs
);
691 if (current
->replacement_session_keyring
)
692 key_replace_session_keyring();