2
* linux/arch/m68knommu/kernel/signal.c
4
* Copyright (C) 1991, 1992 Linus Torvalds
6
* This file is subject to the terms and conditions of the GNU General Public
7
* License. See the file COPYING in the main directory of this archive
12
* Linux/m68k support by Hamish Macdonald
14
* 68060 fixes by Jesper Skov
16
* 1997-12-01 Modified for POSIX.1b signals by Andreas Schwab
18
* mathemu support by Roman Zippel
19
* (Note: fpstate in the signal context is completely ignored for the emulator
20
* and the internal floating point format is put on stack)
24
* ++roman (07/09/96): implemented signal stacks (specially for tosemu on
25
* Atari :-) Current limitation: Only one sigstack can be active at one time.
26
* If a second signal with SA_ONSTACK set arrives while working on a sigstack,
27
* SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested
31
#include <linux/sched.h>
33
#include <linux/kernel.h>
34
#include <linux/signal.h>
35
#include <linux/syscalls.h>
36
#include <linux/errno.h>
37
#include <linux/wait.h>
38
#include <linux/ptrace.h>
39
#include <linux/unistd.h>
40
#include <linux/stddef.h>
41
#include <linux/highuid.h>
42
#include <linux/tty.h>
43
#include <linux/personality.h>
44
#include <linux/binfmts.h>
46
#include <asm/setup.h>
47
#include <asm/uaccess.h>
48
#include <asm/pgtable.h>
49
#include <asm/traps.h>
50
#include <asm/ucontext.h>
52
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
54
void ret_from_user_signal(void);
55
void ret_from_user_rt_signal(void);
58
* Atomically swap in the new signal mask, and wait for a signal.
61
sys_sigsuspend(int unused0, int unused1, old_sigset_t mask)
64
spin_lock_irq(¤t->sighand->siglock);
65
current->saved_sigmask = current->blocked;
66
siginitset(¤t->blocked, mask);
68
spin_unlock_irq(¤t->sighand->siglock);
70
current->state = TASK_INTERRUPTIBLE;
72
set_restore_sigmask();
74
return -ERESTARTNOHAND;
78
sys_sigaction(int sig, const struct old_sigaction __user *act,
79
struct old_sigaction __user *oact)
81
struct k_sigaction new_ka, old_ka;
86
if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
87
__get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
88
__get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
89
__get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
90
__get_user(mask, &act->sa_mask))
92
siginitset(&new_ka.sa.sa_mask, mask);
95
ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
98
if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
99
__put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
100
__put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
101
__put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
102
__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
110
sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
112
return do_sigaltstack(uss, uoss, rdusp());
117
* Do a signal return; undo the signal stack.
119
* Keep the return code on the stack quadword aligned!
120
* That makes the cache flush below easier.
125
char __user *pretcode;
128
struct sigcontext __user *psc;
130
unsigned long extramask[_NSIG_WORDS-1];
131
struct sigcontext sc;
136
char __user *pretcode;
138
struct siginfo __user *pinfo;
147
static unsigned char fpu_version = 0; /* version number of fpu, set by setup_frame */
149
static inline int restore_fpu_state(struct sigcontext *sc)
154
/* restore registers */
155
memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12);
156
memcpy(current->thread.fp, sc->sc_fpregs, 24);
160
if (sc->sc_fpstate[0]) {
161
/* Verify the frame format. */
162
if (sc->sc_fpstate[0] != fpu_version)
165
__asm__ volatile (".chip 68k/68881\n\t"
166
"fmovemx %0,%%fp0-%%fp1\n\t"
167
"fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
170
: "m" (*sc->sc_fpregs), "m" (*sc->sc_fpcntl));
172
__asm__ volatile (".chip 68k/68881\n\t"
174
".chip 68k" : : "m" (*sc->sc_fpstate));
181
#define FPCONTEXT_SIZE 216
182
#define uc_fpstate uc_filler[0]
183
#define uc_formatvec uc_filler[FPCONTEXT_SIZE/4]
184
#define uc_extra uc_filler[FPCONTEXT_SIZE/4+1]
186
static inline int rt_restore_fpu_state(struct ucontext __user *uc)
188
unsigned char fpstate[FPCONTEXT_SIZE];
189
int context_size = 0;
194
/* restore fpu control register */
195
if (__copy_from_user(current->thread.fpcntl,
196
uc->uc_mcontext.fpregs.f_fpcntl, 12))
198
/* restore all other fpu register */
199
if (__copy_from_user(current->thread.fp,
200
uc->uc_mcontext.fpregs.f_fpregs, 96))
205
if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate))
208
context_size = fpstate[1];
210
/* Verify the frame format. */
211
if (fpstate[0] != fpu_version)
213
if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs,
216
__asm__ volatile (".chip 68k/68881\n\t"
217
"fmovemx %0,%%fp0-%%fp7\n\t"
218
"fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
221
: "m" (*fpregs.f_fpregs),
222
"m" (*fpregs.f_fpcntl));
225
__copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1,
228
__asm__ volatile (".chip 68k/68881\n\t"
230
".chip 68k" : : "m" (*fpstate));
240
restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp,
244
struct sigcontext context;
247
/* Always make any pending restarted system calls return -EINTR */
248
current_thread_info()->restart_block.fn = do_no_restart_syscall;
250
/* get previous context */
251
if (copy_from_user(&context, usc, sizeof(context)))
254
/* restore passed registers */
255
regs->d1 = context.sc_d1;
256
regs->a0 = context.sc_a0;
257
regs->a1 = context.sc_a1;
258
((struct switch_stack *)regs - 1)->a5 = context.sc_a5;
259
regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff);
260
regs->pc = context.sc_pc;
261
regs->orig_d0 = -1; /* disable syscall checks */
262
wrusp(context.sc_usp);
263
formatvec = context.sc_formatvec;
264
regs->format = formatvec >> 12;
265
regs->vector = formatvec & 0xfff;
268
err = restore_fpu_state(&context);
271
*pd0 = context.sc_d0;
279
rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
280
struct ucontext __user *uc, int *pd0)
283
greg_t __user *gregs = uc->uc_mcontext.gregs;
287
/* Always make any pending restarted system calls return -EINTR */
288
current_thread_info()->restart_block.fn = do_no_restart_syscall;
290
err = __get_user(temp, &uc->uc_mcontext.version);
291
if (temp != MCONTEXT_VERSION)
293
/* restore passed registers */
294
err |= __get_user(regs->d0, &gregs[0]);
295
err |= __get_user(regs->d1, &gregs[1]);
296
err |= __get_user(regs->d2, &gregs[2]);
297
err |= __get_user(regs->d3, &gregs[3]);
298
err |= __get_user(regs->d4, &gregs[4]);
299
err |= __get_user(regs->d5, &gregs[5]);
300
err |= __get_user(sw->d6, &gregs[6]);
301
err |= __get_user(sw->d7, &gregs[7]);
302
err |= __get_user(regs->a0, &gregs[8]);
303
err |= __get_user(regs->a1, &gregs[9]);
304
err |= __get_user(regs->a2, &gregs[10]);
305
err |= __get_user(sw->a3, &gregs[11]);
306
err |= __get_user(sw->a4, &gregs[12]);
307
err |= __get_user(sw->a5, &gregs[13]);
308
err |= __get_user(sw->a6, &gregs[14]);
309
err |= __get_user(usp, &gregs[15]);
311
err |= __get_user(regs->pc, &gregs[16]);
312
err |= __get_user(temp, &gregs[17]);
313
regs->sr = (regs->sr & 0xff00) | (temp & 0xff);
314
regs->orig_d0 = -1; /* disable syscall checks */
315
regs->format = temp >> 12;
316
regs->vector = temp & 0xfff;
318
if (do_sigaltstack(&uc->uc_stack, NULL, usp) == -EFAULT)
328
asmlinkage int do_sigreturn(unsigned long __unused)
330
struct switch_stack *sw = (struct switch_stack *) &__unused;
331
struct pt_regs *regs = (struct pt_regs *) (sw + 1);
332
unsigned long usp = rdusp();
333
struct sigframe __user *frame = (struct sigframe __user *)(usp - 4);
337
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
339
if (__get_user(set.sig[0], &frame->sc.sc_mask) ||
341
__copy_from_user(&set.sig[1], &frame->extramask,
342
sizeof(frame->extramask))))
345
sigdelsetmask(&set, ~_BLOCKABLE);
346
spin_lock_irq(¤t->sighand->siglock);
347
current->blocked = set;
349
spin_unlock_irq(¤t->sighand->siglock);
351
if (restore_sigcontext(regs, &frame->sc, frame + 1, &d0))
356
force_sig(SIGSEGV, current);
360
asmlinkage int do_rt_sigreturn(unsigned long __unused)
362
struct switch_stack *sw = (struct switch_stack *) &__unused;
363
struct pt_regs *regs = (struct pt_regs *) (sw + 1);
364
unsigned long usp = rdusp();
365
struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4);
369
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
371
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
374
sigdelsetmask(&set, ~_BLOCKABLE);
375
spin_lock_irq(¤t->sighand->siglock);
376
current->blocked = set;
378
spin_unlock_irq(¤t->sighand->siglock);
380
if (rt_restore_ucontext(regs, sw, &frame->uc, &d0))
385
force_sig(SIGSEGV, current);
391
* Set up a signal frame.
394
static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
398
memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12);
399
memcpy(sc->sc_fpregs, current->thread.fp, 24);
403
__asm__ volatile (".chip 68k/68881\n\t"
406
: : "m" (*sc->sc_fpstate) : "memory");
408
if (sc->sc_fpstate[0]) {
409
fpu_version = sc->sc_fpstate[0];
410
__asm__ volatile (".chip 68k/68881\n\t"
411
"fmovemx %%fp0-%%fp1,%0\n\t"
412
"fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
414
: "=m" (*sc->sc_fpregs),
415
"=m" (*sc->sc_fpcntl)
421
static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
423
unsigned char fpstate[FPCONTEXT_SIZE];
424
int context_size = 0;
428
/* save fpu control register */
429
err |= copy_to_user(uc->uc_mcontext.fpregs.f_pcntl,
430
current->thread.fpcntl, 12);
431
/* save all other fpu register */
432
err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs,
433
current->thread.fp, 96);
437
__asm__ volatile (".chip 68k/68881\n\t"
440
: : "m" (*fpstate) : "memory");
442
err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate);
445
context_size = fpstate[1];
446
fpu_version = fpstate[0];
447
__asm__ volatile (".chip 68k/68881\n\t"
448
"fmovemx %%fp0-%%fp7,%0\n\t"
449
"fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
451
: "=m" (*fpregs.f_fpregs),
452
"=m" (*fpregs.f_fpcntl)
455
err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs,
459
err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4,
466
static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
470
sc->sc_usp = rdusp();
471
sc->sc_d0 = regs->d0;
472
sc->sc_d1 = regs->d1;
473
sc->sc_a0 = regs->a0;
474
sc->sc_a1 = regs->a1;
475
sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5;
476
sc->sc_sr = regs->sr;
477
sc->sc_pc = regs->pc;
478
sc->sc_formatvec = regs->format << 12 | regs->vector;
480
save_fpu_state(sc, regs);
484
static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs)
486
struct switch_stack *sw = (struct switch_stack *)regs - 1;
487
greg_t __user *gregs = uc->uc_mcontext.gregs;
490
err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
491
err |= __put_user(regs->d0, &gregs[0]);
492
err |= __put_user(regs->d1, &gregs[1]);
493
err |= __put_user(regs->d2, &gregs[2]);
494
err |= __put_user(regs->d3, &gregs[3]);
495
err |= __put_user(regs->d4, &gregs[4]);
496
err |= __put_user(regs->d5, &gregs[5]);
497
err |= __put_user(sw->d6, &gregs[6]);
498
err |= __put_user(sw->d7, &gregs[7]);
499
err |= __put_user(regs->a0, &gregs[8]);
500
err |= __put_user(regs->a1, &gregs[9]);
501
err |= __put_user(regs->a2, &gregs[10]);
502
err |= __put_user(sw->a3, &gregs[11]);
503
err |= __put_user(sw->a4, &gregs[12]);
504
err |= __put_user(sw->a5, &gregs[13]);
505
err |= __put_user(sw->a6, &gregs[14]);
506
err |= __put_user(rdusp(), &gregs[15]);
507
err |= __put_user(regs->pc, &gregs[16]);
508
err |= __put_user(regs->sr, &gregs[17]);
510
err |= rt_save_fpu_state(uc, regs);
515
static inline void __user *
516
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
520
/* Default to using normal stack. */
523
/* This is the X/Open sanctioned signal stack switching. */
524
if (ka->sa.sa_flags & SA_ONSTACK) {
525
if (!sas_ss_flags(usp))
526
usp = current->sas_ss_sp + current->sas_ss_size;
528
return (void __user *)((usp - frame_size) & -8UL);
531
static int setup_frame (int sig, struct k_sigaction *ka,
532
sigset_t *set, struct pt_regs *regs)
534
struct sigframe __user *frame;
535
struct sigcontext context;
538
frame = get_sigframe(ka, regs, sizeof(*frame));
540
err |= __put_user((current_thread_info()->exec_domain
541
&& current_thread_info()->exec_domain->signal_invmap
543
? current_thread_info()->exec_domain->signal_invmap[sig]
547
err |= __put_user(regs->vector, &frame->code);
548
err |= __put_user(&frame->sc, &frame->psc);
551
err |= copy_to_user(frame->extramask, &set->sig[1],
552
sizeof(frame->extramask));
554
setup_sigcontext(&context, regs, set->sig[0]);
555
err |= copy_to_user (&frame->sc, &context, sizeof(context));
557
/* Set up to return from userspace. */
558
err |= __put_user((void *) ret_from_user_signal, &frame->pretcode);
563
/* Set up registers for signal handler */
564
wrusp ((unsigned long) frame);
565
regs->pc = (unsigned long) ka->sa.sa_handler;
566
((struct switch_stack *)regs - 1)->a5 = current->mm->start_data;
567
regs->format = 0x4; /*set format byte to make stack appear modulo 4
568
which it will be when doing the rte */
571
/* Prepare to skip over the extra stuff in the exception frame. */
573
struct pt_regs *tregs =
574
(struct pt_regs *)((ulong)regs + regs->stkadj);
576
printk(KERN_DEBUG "Performing stackadjust=%04x\n", regs->stkadj);
578
/* This must be copied with decreasing addresses to
582
tregs->pc = regs->pc;
583
tregs->sr = regs->sr;
588
force_sigsegv(sig, current);
592
static int setup_rt_frame (int sig, struct k_sigaction *ka, siginfo_t *info,
593
sigset_t *set, struct pt_regs *regs)
595
struct rt_sigframe __user *frame;
598
frame = get_sigframe(ka, regs, sizeof(*frame));
600
err |= __put_user((current_thread_info()->exec_domain
601
&& current_thread_info()->exec_domain->signal_invmap
603
? current_thread_info()->exec_domain->signal_invmap[sig]
606
err |= __put_user(&frame->info, &frame->pinfo);
607
err |= __put_user(&frame->uc, &frame->puc);
608
err |= copy_siginfo_to_user(&frame->info, info);
610
/* Create the ucontext. */
611
err |= __put_user(0, &frame->uc.uc_flags);
612
err |= __put_user(NULL, &frame->uc.uc_link);
613
err |= __put_user((void __user *)current->sas_ss_sp,
614
&frame->uc.uc_stack.ss_sp);
615
err |= __put_user(sas_ss_flags(rdusp()),
616
&frame->uc.uc_stack.ss_flags);
617
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
618
err |= rt_setup_ucontext(&frame->uc, regs);
619
err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set));
621
/* Set up to return from userspace. */
622
err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode);
627
/* Set up registers for signal handler */
628
wrusp ((unsigned long) frame);
629
regs->pc = (unsigned long) ka->sa.sa_handler;
630
((struct switch_stack *)regs - 1)->a5 = current->mm->start_data;
631
regs->format = 0x4; /*set format byte to make stack appear modulo 4
632
which it will be when doing the rte */
635
/* Prepare to skip over the extra stuff in the exception frame. */
637
struct pt_regs *tregs =
638
(struct pt_regs *)((ulong)regs + regs->stkadj);
640
printk(KERN_DEBUG "Performing stackadjust=%04x\n", regs->stkadj);
642
/* This must be copied with decreasing addresses to
646
tregs->pc = regs->pc;
647
tregs->sr = regs->sr;
652
force_sigsegv(sig, current);
657
handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
660
case -ERESTARTNOHAND:
666
case -ERESTART_RESTARTBLOCK:
668
regs->d0 = __NR_restart_syscall;
676
if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
681
case -ERESTARTNOINTR:
683
regs->d0 = regs->orig_d0;
690
* OK, we're invoking a handler
693
handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
694
sigset_t *oldset, struct pt_regs *regs)
697
/* are we from a system call? */
698
if (regs->orig_d0 >= 0)
699
/* If so, check system call restarting.. */
700
handle_restart(regs, ka, 1);
702
/* set up the stack frame */
703
if (ka->sa.sa_flags & SA_SIGINFO)
704
err = setup_rt_frame(sig, ka, info, oldset, regs);
706
err = setup_frame(sig, ka, oldset, regs);
711
spin_lock_irq(¤t->sighand->siglock);
712
sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
713
if (!(ka->sa.sa_flags & SA_NODEFER))
714
sigaddset(¤t->blocked,sig);
716
spin_unlock_irq(¤t->sighand->siglock);
718
clear_thread_flag(TIF_RESTORE_SIGMASK);
722
* Note that 'init' is a special process: it doesn't get signals it doesn't
723
* want to handle. Thus you cannot kill init even with a SIGKILL even by
726
asmlinkage void do_signal(struct pt_regs *regs)
728
struct k_sigaction ka;
734
* We want the common case to go fast, which
735
* is why we may in certain cases get here from
736
* kernel mode. Just return without doing anything
739
if (!user_mode(regs))
742
if (test_thread_flag(TIF_RESTORE_SIGMASK))
743
oldset = ¤t->saved_sigmask;
745
oldset = ¤t->blocked;
747
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
749
/* Whee! Actually deliver the signal. */
750
handle_signal(signr, &ka, &info, oldset, regs);
754
/* Did we come from a system call? */
755
if (regs->orig_d0 >= 0) {
756
/* Restart the system call - no handlers present */
757
handle_restart(regs, NULL, 0);
760
/* If there's no signal to deliver, we just restore the saved mask. */
761
if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
762
clear_thread_flag(TIF_RESTORE_SIGMASK);
763
sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);