1 /* linux/arch/sparc/kernel/signal.c
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
5 * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
6 * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
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/tty.h>
18 #include <linux/smp.h>
19 #include <linux/binfmts.h> /* do_coredum */
20 #include <linux/bitops.h>
21 #include <linux/tracehook.h>
23 #include <asm/uaccess.h>
24 #include <asm/ptrace.h>
25 #include <asm/pgalloc.h>
26 #include <asm/pgtable.h>
27 #include <asm/cacheflush.h> /* flush_sig_insns */
28 #include <asm/switch_to.h>
32 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
34 extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
35 void *fpqueue, unsigned long *fpqdepth);
36 extern void fpload(unsigned long *fpregs, unsigned long *fsr);
39 struct sparc_stackf ss;
41 __siginfo_fpu_t __user *fpu_save;
42 unsigned long insns[2] __attribute__ ((aligned (8)));
43 unsigned int extramask[_NSIG_WORDS - 1];
44 unsigned int extra_size; /* Should be 0 */
45 __siginfo_rwin_t __user *rwin_save;
46 } __attribute__((aligned(8)));
48 struct rt_signal_frame {
49 struct sparc_stackf ss;
53 __siginfo_fpu_t __user *fpu_save;
54 unsigned int insns[2];
56 unsigned int extra_size; /* Should be 0 */
57 __siginfo_rwin_t __user *rwin_save;
58 } __attribute__((aligned(8)));
61 #define SF_ALIGNEDSZ (((sizeof(struct signal_frame) + 7) & (~7)))
62 #define RT_ALIGNEDSZ (((sizeof(struct rt_signal_frame) + 7) & (~7)))
64 static int _sigpause_common(old_sigset_t set)
67 siginitset(&blocked, set);
68 return sigsuspend(&blocked);
71 asmlinkage int sys_sigsuspend(old_sigset_t set)
73 return _sigpause_common(set);
76 asmlinkage void do_sigreturn(struct pt_regs *regs)
78 struct signal_frame __user *sf;
79 unsigned long up_psr, pc, npc;
81 __siginfo_fpu_t __user *fpu_save;
82 __siginfo_rwin_t __user *rwin_save;
85 /* Always make any pending restarted system calls return -EINTR */
86 current_thread_info()->restart_block.fn = do_no_restart_syscall;
88 synchronize_user_stack();
90 sf = (struct signal_frame __user *) regs->u_regs[UREG_FP];
92 /* 1. Make sure we are not getting garbage from the user */
93 if (!access_ok(VERIFY_READ, sf, sizeof(*sf)))
96 if (((unsigned long) sf) & 3)
99 err = __get_user(pc, &sf->info.si_regs.pc);
100 err |= __get_user(npc, &sf->info.si_regs.npc);
105 /* 2. Restore the state */
107 err |= __copy_from_user(regs, &sf->info.si_regs, sizeof(struct pt_regs));
109 /* User can only change condition codes and FPU enabling in %psr. */
110 regs->psr = (up_psr & ~(PSR_ICC | PSR_EF))
111 | (regs->psr & (PSR_ICC | PSR_EF));
113 /* Prevent syscall restart. */
114 pt_regs_clear_syscall(regs);
116 err |= __get_user(fpu_save, &sf->fpu_save);
118 err |= restore_fpu_state(regs, fpu_save);
119 err |= __get_user(rwin_save, &sf->rwin_save);
121 err |= restore_rwin_state(rwin_save);
123 /* This is pretty much atomic, no amount locking would prevent
124 * the races which exist anyways.
126 err |= __get_user(set.sig[0], &sf->info.si_mask);
127 err |= __copy_from_user(&set.sig[1], &sf->extramask,
128 (_NSIG_WORDS-1) * sizeof(unsigned int));
133 sigdelsetmask(&set, ~_BLOCKABLE);
134 set_current_blocked(&set);
138 force_sig(SIGSEGV, current);
141 asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
143 struct rt_signal_frame __user *sf;
144 unsigned int psr, pc, npc;
145 __siginfo_fpu_t __user *fpu_save;
146 __siginfo_rwin_t __user *rwin_save;
152 synchronize_user_stack();
153 sf = (struct rt_signal_frame __user *) regs->u_regs[UREG_FP];
154 if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
155 (((unsigned long) sf) & 0x03))
158 err = __get_user(pc, &sf->regs.pc);
159 err |= __get_user(npc, &sf->regs.npc);
160 err |= ((pc | npc) & 0x03);
162 err |= __get_user(regs->y, &sf->regs.y);
163 err |= __get_user(psr, &sf->regs.psr);
165 err |= __copy_from_user(®s->u_regs[UREG_G1],
166 &sf->regs.u_regs[UREG_G1], 15 * sizeof(u32));
168 regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC);
170 /* Prevent syscall restart. */
171 pt_regs_clear_syscall(regs);
173 err |= __get_user(fpu_save, &sf->fpu_save);
174 if (!err && fpu_save)
175 err |= restore_fpu_state(regs, fpu_save);
176 err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
178 err |= __copy_from_user(&st, &sf->stack, sizeof(stack_t));
186 /* It is more difficult to avoid calling this function than to
187 * call it and ignore errors.
191 do_sigaltstack((const stack_t __user *) &st, NULL, (unsigned long)sf);
194 err |= __get_user(rwin_save, &sf->rwin_save);
195 if (!err && rwin_save) {
196 if (restore_rwin_state(rwin_save))
200 sigdelsetmask(&set, ~_BLOCKABLE);
201 set_current_blocked(&set);
204 force_sig(SIGSEGV, current);
207 /* Checks if the fp is valid */
208 static inline int invalid_frame_pointer(void __user *fp, int fplen)
210 if ((((unsigned long) fp) & 7) || !__access_ok((unsigned long)fp, fplen))
216 static inline void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, unsigned long framesize)
218 unsigned long sp = regs->u_regs[UREG_FP];
221 * If we are on the alternate signal stack and would overflow it, don't.
222 * Return an always-bogus address instead so we will die with SIGSEGV.
224 if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
225 return (void __user *) -1L;
227 /* This is the X/Open sanctioned signal stack switching. */
228 if (sa->sa_flags & SA_ONSTACK) {
229 if (sas_ss_flags(sp) == 0)
230 sp = current->sas_ss_sp + current->sas_ss_size;
235 /* Always align the stack frame. This handles two cases. First,
236 * sigaltstack need not be mindful of platform specific stack
237 * alignment. Second, if we took this signal because the stack
238 * is not aligned properly, we'd like to take the signal cleanly
243 return (void __user *) sp;
246 static int setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
247 int signo, sigset_t *oldset)
249 struct signal_frame __user *sf;
250 int sigframe_size, err, wsaved;
253 /* 1. Make sure everything is clean */
254 synchronize_user_stack();
256 wsaved = current_thread_info()->w_saved;
258 sigframe_size = sizeof(*sf);
260 sigframe_size += sizeof(__siginfo_fpu_t);
262 sigframe_size += sizeof(__siginfo_rwin_t);
264 sf = (struct signal_frame __user *)
265 get_sigframe(&ka->sa, regs, sigframe_size);
267 if (invalid_frame_pointer(sf, sigframe_size))
268 goto sigill_and_return;
272 /* 2. Save the current process state */
273 err = __copy_to_user(&sf->info.si_regs, regs, sizeof(struct pt_regs));
275 err |= __put_user(0, &sf->extra_size);
278 __siginfo_fpu_t __user *fp = tail;
280 err |= save_fpu_state(regs, fp);
281 err |= __put_user(fp, &sf->fpu_save);
283 err |= __put_user(0, &sf->fpu_save);
286 __siginfo_rwin_t __user *rwp = tail;
287 tail += sizeof(*rwp);
288 err |= save_rwin_state(wsaved, rwp);
289 err |= __put_user(rwp, &sf->rwin_save);
291 err |= __put_user(0, &sf->rwin_save);
294 err |= __put_user(oldset->sig[0], &sf->info.si_mask);
295 err |= __copy_to_user(sf->extramask, &oldset->sig[1],
296 (_NSIG_WORDS - 1) * sizeof(unsigned int));
298 err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP],
299 sizeof(struct reg_window32));
301 struct reg_window32 *rp;
303 rp = ¤t_thread_info()->reg_window[wsaved - 1];
304 err |= __copy_to_user(sf, rp, sizeof(struct reg_window32));
309 /* 3. signal handler back-trampoline and parameters */
310 regs->u_regs[UREG_FP] = (unsigned long) sf;
311 regs->u_regs[UREG_I0] = signo;
312 regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
313 regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
315 /* 4. signal handler */
316 regs->pc = (unsigned long) ka->sa.sa_handler;
317 regs->npc = (regs->pc + 4);
319 /* 5. return to kernel instructions */
321 regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
323 regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2);
325 /* mov __NR_sigreturn, %g1 */
326 err |= __put_user(0x821020d8, &sf->insns[0]);
329 err |= __put_user(0x91d02010, &sf->insns[1]);
333 /* Flush instruction space. */
334 flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
343 force_sigsegv(signo, current);
347 static int setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
348 int signo, sigset_t *oldset, siginfo_t *info)
350 struct rt_signal_frame __user *sf;
351 int sigframe_size, wsaved;
356 synchronize_user_stack();
357 wsaved = current_thread_info()->w_saved;
358 sigframe_size = sizeof(*sf);
360 sigframe_size += sizeof(__siginfo_fpu_t);
362 sigframe_size += sizeof(__siginfo_rwin_t);
363 sf = (struct rt_signal_frame __user *)
364 get_sigframe(&ka->sa, regs, sigframe_size);
365 if (invalid_frame_pointer(sf, sigframe_size))
369 err = __put_user(regs->pc, &sf->regs.pc);
370 err |= __put_user(regs->npc, &sf->regs.npc);
371 err |= __put_user(regs->y, &sf->regs.y);
375 err |= __put_user(psr, &sf->regs.psr);
376 err |= __copy_to_user(&sf->regs.u_regs, regs->u_regs, sizeof(regs->u_regs));
377 err |= __put_user(0, &sf->extra_size);
380 __siginfo_fpu_t *fp = tail;
382 err |= save_fpu_state(regs, fp);
383 err |= __put_user(fp, &sf->fpu_save);
385 err |= __put_user(0, &sf->fpu_save);
388 __siginfo_rwin_t *rwp = tail;
389 tail += sizeof(*rwp);
390 err |= save_rwin_state(wsaved, rwp);
391 err |= __put_user(rwp, &sf->rwin_save);
393 err |= __put_user(0, &sf->rwin_save);
395 err |= __copy_to_user(&sf->mask, &oldset->sig[0], sizeof(sigset_t));
397 /* Setup sigaltstack */
398 err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
399 err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
400 err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
403 err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP],
404 sizeof(struct reg_window32));
406 struct reg_window32 *rp;
408 rp = ¤t_thread_info()->reg_window[wsaved - 1];
409 err |= __copy_to_user(sf, rp, sizeof(struct reg_window32));
412 err |= copy_siginfo_to_user(&sf->info, info);
417 regs->u_regs[UREG_FP] = (unsigned long) sf;
418 regs->u_regs[UREG_I0] = signo;
419 regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
420 regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
422 regs->pc = (unsigned long) ka->sa.sa_handler;
423 regs->npc = (regs->pc + 4);
426 regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
428 regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2);
430 /* mov __NR_sigreturn, %g1 */
431 err |= __put_user(0x821020d8, &sf->insns[0]);
434 err |= __put_user(0x91d02010, &sf->insns[1]);
438 /* Flush instruction space. */
439 flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
448 force_sigsegv(signo, current);
453 handle_signal(unsigned long signr, struct k_sigaction *ka,
454 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
458 if (ka->sa.sa_flags & SA_SIGINFO)
459 err = setup_rt_frame(ka, regs, signr, oldset, info);
461 err = setup_frame(ka, regs, signr, oldset);
466 block_sigmask(ka, signr);
467 tracehook_signal_handler(signr, info, ka, regs, 0);
472 static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
473 struct sigaction *sa)
475 switch(regs->u_regs[UREG_I0]) {
476 case ERESTART_RESTARTBLOCK:
478 no_system_call_restart:
479 regs->u_regs[UREG_I0] = EINTR;
483 if (!(sa->sa_flags & SA_RESTART))
484 goto no_system_call_restart;
487 regs->u_regs[UREG_I0] = orig_i0;
493 /* Note that 'init' is a special process: it doesn't get signals it doesn't
494 * want to handle. Thus you cannot kill init even with a SIGKILL even by
497 static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
499 struct k_sigaction ka;
505 /* It's a lot of work and synchronization to add a new ptrace
506 * register for GDB to save and restore in order to get
507 * orig_i0 correct for syscall restarts when debugging.
509 * Although it should be the case that most of the global
510 * registers are volatile across a system call, glibc already
511 * depends upon that fact that we preserve them. So we can't
512 * just use any global register to save away the orig_i0 value.
514 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
515 * preserved across a system call trap by various pieces of
518 * %g7 is used as the "thread register". %g6 is not used in
519 * any fixed manner. %g6 is used as a scratch register and
520 * a compiler temporary, but it's value is never used across
521 * a system call. Therefore %g6 is usable for orig_i0 storage.
523 if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C))
524 regs->u_regs[UREG_G6] = orig_i0;
526 if (test_thread_flag(TIF_RESTORE_SIGMASK))
527 oldset = ¤t->saved_sigmask;
529 oldset = ¤t->blocked;
531 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
533 /* If the debugger messes with the program counter, it clears
534 * the software "in syscall" bit, directing us to not perform
538 if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) {
540 orig_i0 = regs->u_regs[UREG_G6];
546 syscall_restart(orig_i0, regs, &ka.sa);
547 if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
548 /* a signal was successfully delivered; the saved
549 * sigmask will have been stored in the signal frame,
550 * and will be restored by sigreturn, so we can simply
551 * clear the TIF_RESTORE_SIGMASK flag.
553 if (test_thread_flag(TIF_RESTORE_SIGMASK))
554 clear_thread_flag(TIF_RESTORE_SIGMASK);
558 if (restart_syscall &&
559 (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
560 regs->u_regs[UREG_I0] == ERESTARTSYS ||
561 regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
562 /* replay the system call when we are done */
563 regs->u_regs[UREG_I0] = orig_i0;
566 pt_regs_clear_syscall(regs);
568 if (restart_syscall &&
569 regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
570 regs->u_regs[UREG_G1] = __NR_restart_syscall;
573 pt_regs_clear_syscall(regs);
576 /* if there's no signal to deliver, we just put the saved sigmask
579 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
580 clear_thread_flag(TIF_RESTORE_SIGMASK);
581 set_current_blocked(¤t->saved_sigmask);
585 void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0,
586 unsigned long thread_info_flags)
588 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
589 do_signal(regs, orig_i0);
590 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
591 clear_thread_flag(TIF_NOTIFY_RESUME);
592 tracehook_notify_resume(regs);
593 if (current->replacement_session_keyring)
594 key_replace_session_keyring();
599 do_sys_sigstack(struct sigstack __user *ssptr, struct sigstack __user *ossptr,
604 /* First see if old state is wanted. */
606 if (put_user(current->sas_ss_sp + current->sas_ss_size,
607 &ossptr->the_stack) ||
608 __put_user(on_sig_stack(sp), &ossptr->cur_status))
612 /* Now see if we want to update the new state. */
616 if (get_user(ss_sp, &ssptr->the_stack))
618 /* If the current stack was set with sigaltstack, don't
619 swap stacks while we are on it. */
621 if (current->sas_ss_sp && on_sig_stack(sp))
624 /* Since we don't know the extent of the stack, and we don't
625 track onstack-ness, but rather calculate it, we must
626 presume a size. Ho hum this interface is lossy. */
627 current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
628 current->sas_ss_size = SIGSTKSZ;