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)
68 current->saved_sigmask = current->blocked;
71 siginitset(&blocked, set);
72 set_current_blocked(&blocked);
74 current->state = TASK_INTERRUPTIBLE;
76 set_thread_flag(TIF_RESTORE_SIGMASK);
78 return -ERESTARTNOHAND;
81 asmlinkage int sys_sigsuspend(old_sigset_t set)
83 return _sigpause_common(set);
86 asmlinkage void do_sigreturn(struct pt_regs *regs)
88 struct signal_frame __user *sf;
89 unsigned long up_psr, pc, npc;
91 __siginfo_fpu_t __user *fpu_save;
92 __siginfo_rwin_t __user *rwin_save;
95 /* Always make any pending restarted system calls return -EINTR */
96 current_thread_info()->restart_block.fn = do_no_restart_syscall;
98 synchronize_user_stack();
100 sf = (struct signal_frame __user *) regs->u_regs[UREG_FP];
102 /* 1. Make sure we are not getting garbage from the user */
103 if (!access_ok(VERIFY_READ, sf, sizeof(*sf)))
106 if (((unsigned long) sf) & 3)
109 err = __get_user(pc, &sf->info.si_regs.pc);
110 err |= __get_user(npc, &sf->info.si_regs.npc);
115 /* 2. Restore the state */
117 err |= __copy_from_user(regs, &sf->info.si_regs, sizeof(struct pt_regs));
119 /* User can only change condition codes and FPU enabling in %psr. */
120 regs->psr = (up_psr & ~(PSR_ICC | PSR_EF))
121 | (regs->psr & (PSR_ICC | PSR_EF));
123 /* Prevent syscall restart. */
124 pt_regs_clear_syscall(regs);
126 err |= __get_user(fpu_save, &sf->fpu_save);
128 err |= restore_fpu_state(regs, fpu_save);
129 err |= __get_user(rwin_save, &sf->rwin_save);
131 err |= restore_rwin_state(rwin_save);
133 /* This is pretty much atomic, no amount locking would prevent
134 * the races which exist anyways.
136 err |= __get_user(set.sig[0], &sf->info.si_mask);
137 err |= __copy_from_user(&set.sig[1], &sf->extramask,
138 (_NSIG_WORDS-1) * sizeof(unsigned int));
143 sigdelsetmask(&set, ~_BLOCKABLE);
144 set_current_blocked(&set);
148 force_sig(SIGSEGV, current);
151 asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
153 struct rt_signal_frame __user *sf;
154 unsigned int psr, pc, npc;
155 __siginfo_fpu_t __user *fpu_save;
156 __siginfo_rwin_t __user *rwin_save;
162 synchronize_user_stack();
163 sf = (struct rt_signal_frame __user *) regs->u_regs[UREG_FP];
164 if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
165 (((unsigned long) sf) & 0x03))
168 err = __get_user(pc, &sf->regs.pc);
169 err |= __get_user(npc, &sf->regs.npc);
170 err |= ((pc | npc) & 0x03);
172 err |= __get_user(regs->y, &sf->regs.y);
173 err |= __get_user(psr, &sf->regs.psr);
175 err |= __copy_from_user(®s->u_regs[UREG_G1],
176 &sf->regs.u_regs[UREG_G1], 15 * sizeof(u32));
178 regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC);
180 /* Prevent syscall restart. */
181 pt_regs_clear_syscall(regs);
183 err |= __get_user(fpu_save, &sf->fpu_save);
184 if (!err && fpu_save)
185 err |= restore_fpu_state(regs, fpu_save);
186 err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
188 err |= __copy_from_user(&st, &sf->stack, sizeof(stack_t));
196 /* It is more difficult to avoid calling this function than to
197 * call it and ignore errors.
201 do_sigaltstack((const stack_t __user *) &st, NULL, (unsigned long)sf);
204 err |= __get_user(rwin_save, &sf->rwin_save);
205 if (!err && rwin_save) {
206 if (restore_rwin_state(rwin_save))
210 sigdelsetmask(&set, ~_BLOCKABLE);
211 set_current_blocked(&set);
214 force_sig(SIGSEGV, current);
217 /* Checks if the fp is valid */
218 static inline int invalid_frame_pointer(void __user *fp, int fplen)
220 if ((((unsigned long) fp) & 7) ||
221 !__access_ok((unsigned long)fp, fplen) ||
222 ((sparc_cpu_model == sun4 || sparc_cpu_model == sun4c) &&
223 ((unsigned long) fp < 0xe0000000 && (unsigned long) fp >= 0x20000000)))
229 static inline void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, unsigned long framesize)
231 unsigned long sp = regs->u_regs[UREG_FP];
234 * If we are on the alternate signal stack and would overflow it, don't.
235 * Return an always-bogus address instead so we will die with SIGSEGV.
237 if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
238 return (void __user *) -1L;
240 /* This is the X/Open sanctioned signal stack switching. */
241 if (sa->sa_flags & SA_ONSTACK) {
242 if (sas_ss_flags(sp) == 0)
243 sp = current->sas_ss_sp + current->sas_ss_size;
248 /* Always align the stack frame. This handles two cases. First,
249 * sigaltstack need not be mindful of platform specific stack
250 * alignment. Second, if we took this signal because the stack
251 * is not aligned properly, we'd like to take the signal cleanly
256 return (void __user *) sp;
259 static int setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
260 int signo, sigset_t *oldset)
262 struct signal_frame __user *sf;
263 int sigframe_size, err, wsaved;
266 /* 1. Make sure everything is clean */
267 synchronize_user_stack();
269 wsaved = current_thread_info()->w_saved;
271 sigframe_size = sizeof(*sf);
273 sigframe_size += sizeof(__siginfo_fpu_t);
275 sigframe_size += sizeof(__siginfo_rwin_t);
277 sf = (struct signal_frame __user *)
278 get_sigframe(&ka->sa, regs, sigframe_size);
280 if (invalid_frame_pointer(sf, sigframe_size))
281 goto sigill_and_return;
285 /* 2. Save the current process state */
286 err = __copy_to_user(&sf->info.si_regs, regs, sizeof(struct pt_regs));
288 err |= __put_user(0, &sf->extra_size);
291 __siginfo_fpu_t __user *fp = tail;
293 err |= save_fpu_state(regs, fp);
294 err |= __put_user(fp, &sf->fpu_save);
296 err |= __put_user(0, &sf->fpu_save);
299 __siginfo_rwin_t __user *rwp = tail;
300 tail += sizeof(*rwp);
301 err |= save_rwin_state(wsaved, rwp);
302 err |= __put_user(rwp, &sf->rwin_save);
304 err |= __put_user(0, &sf->rwin_save);
307 err |= __put_user(oldset->sig[0], &sf->info.si_mask);
308 err |= __copy_to_user(sf->extramask, &oldset->sig[1],
309 (_NSIG_WORDS - 1) * sizeof(unsigned int));
311 err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP],
312 sizeof(struct reg_window32));
314 struct reg_window32 *rp;
316 rp = ¤t_thread_info()->reg_window[wsaved - 1];
317 err |= __copy_to_user(sf, rp, sizeof(struct reg_window32));
322 /* 3. signal handler back-trampoline and parameters */
323 regs->u_regs[UREG_FP] = (unsigned long) sf;
324 regs->u_regs[UREG_I0] = signo;
325 regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
326 regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
328 /* 4. signal handler */
329 regs->pc = (unsigned long) ka->sa.sa_handler;
330 regs->npc = (regs->pc + 4);
332 /* 5. return to kernel instructions */
334 regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
336 regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2);
338 /* mov __NR_sigreturn, %g1 */
339 err |= __put_user(0x821020d8, &sf->insns[0]);
342 err |= __put_user(0x91d02010, &sf->insns[1]);
346 /* Flush instruction space. */
347 flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
356 force_sigsegv(signo, current);
360 static int setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
361 int signo, sigset_t *oldset, siginfo_t *info)
363 struct rt_signal_frame __user *sf;
364 int sigframe_size, wsaved;
369 synchronize_user_stack();
370 wsaved = current_thread_info()->w_saved;
371 sigframe_size = sizeof(*sf);
373 sigframe_size += sizeof(__siginfo_fpu_t);
375 sigframe_size += sizeof(__siginfo_rwin_t);
376 sf = (struct rt_signal_frame __user *)
377 get_sigframe(&ka->sa, regs, sigframe_size);
378 if (invalid_frame_pointer(sf, sigframe_size))
382 err = __put_user(regs->pc, &sf->regs.pc);
383 err |= __put_user(regs->npc, &sf->regs.npc);
384 err |= __put_user(regs->y, &sf->regs.y);
388 err |= __put_user(psr, &sf->regs.psr);
389 err |= __copy_to_user(&sf->regs.u_regs, regs->u_regs, sizeof(regs->u_regs));
390 err |= __put_user(0, &sf->extra_size);
393 __siginfo_fpu_t *fp = tail;
395 err |= save_fpu_state(regs, fp);
396 err |= __put_user(fp, &sf->fpu_save);
398 err |= __put_user(0, &sf->fpu_save);
401 __siginfo_rwin_t *rwp = tail;
402 tail += sizeof(*rwp);
403 err |= save_rwin_state(wsaved, rwp);
404 err |= __put_user(rwp, &sf->rwin_save);
406 err |= __put_user(0, &sf->rwin_save);
408 err |= __copy_to_user(&sf->mask, &oldset->sig[0], sizeof(sigset_t));
410 /* Setup sigaltstack */
411 err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
412 err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
413 err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
416 err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP],
417 sizeof(struct reg_window32));
419 struct reg_window32 *rp;
421 rp = ¤t_thread_info()->reg_window[wsaved - 1];
422 err |= __copy_to_user(sf, rp, sizeof(struct reg_window32));
425 err |= copy_siginfo_to_user(&sf->info, info);
430 regs->u_regs[UREG_FP] = (unsigned long) sf;
431 regs->u_regs[UREG_I0] = signo;
432 regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
433 regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
435 regs->pc = (unsigned long) ka->sa.sa_handler;
436 regs->npc = (regs->pc + 4);
439 regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
441 regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2);
443 /* mov __NR_sigreturn, %g1 */
444 err |= __put_user(0x821020d8, &sf->insns[0]);
447 err |= __put_user(0x91d02010, &sf->insns[1]);
451 /* Flush instruction space. */
452 flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
461 force_sigsegv(signo, current);
466 handle_signal(unsigned long signr, struct k_sigaction *ka,
467 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
471 if (ka->sa.sa_flags & SA_SIGINFO)
472 err = setup_rt_frame(ka, regs, signr, oldset, info);
474 err = setup_frame(ka, regs, signr, oldset);
479 block_sigmask(ka, signr);
480 tracehook_signal_handler(signr, info, ka, regs, 0);
485 static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
486 struct sigaction *sa)
488 switch(regs->u_regs[UREG_I0]) {
489 case ERESTART_RESTARTBLOCK:
491 no_system_call_restart:
492 regs->u_regs[UREG_I0] = EINTR;
496 if (!(sa->sa_flags & SA_RESTART))
497 goto no_system_call_restart;
500 regs->u_regs[UREG_I0] = orig_i0;
506 /* Note that 'init' is a special process: it doesn't get signals it doesn't
507 * want to handle. Thus you cannot kill init even with a SIGKILL even by
510 static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
512 struct k_sigaction ka;
518 /* It's a lot of work and synchronization to add a new ptrace
519 * register for GDB to save and restore in order to get
520 * orig_i0 correct for syscall restarts when debugging.
522 * Although it should be the case that most of the global
523 * registers are volatile across a system call, glibc already
524 * depends upon that fact that we preserve them. So we can't
525 * just use any global register to save away the orig_i0 value.
527 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
528 * preserved across a system call trap by various pieces of
531 * %g7 is used as the "thread register". %g6 is not used in
532 * any fixed manner. %g6 is used as a scratch register and
533 * a compiler temporary, but it's value is never used across
534 * a system call. Therefore %g6 is usable for orig_i0 storage.
536 if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C))
537 regs->u_regs[UREG_G6] = orig_i0;
539 if (test_thread_flag(TIF_RESTORE_SIGMASK))
540 oldset = ¤t->saved_sigmask;
542 oldset = ¤t->blocked;
544 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
546 /* If the debugger messes with the program counter, it clears
547 * the software "in syscall" bit, directing us to not perform
551 if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) {
553 orig_i0 = regs->u_regs[UREG_G6];
559 syscall_restart(orig_i0, regs, &ka.sa);
560 if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
561 /* a signal was successfully delivered; the saved
562 * sigmask will have been stored in the signal frame,
563 * and will be restored by sigreturn, so we can simply
564 * clear the TIF_RESTORE_SIGMASK flag.
566 if (test_thread_flag(TIF_RESTORE_SIGMASK))
567 clear_thread_flag(TIF_RESTORE_SIGMASK);
571 if (restart_syscall &&
572 (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
573 regs->u_regs[UREG_I0] == ERESTARTSYS ||
574 regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
575 /* replay the system call when we are done */
576 regs->u_regs[UREG_I0] = orig_i0;
579 pt_regs_clear_syscall(regs);
581 if (restart_syscall &&
582 regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
583 regs->u_regs[UREG_G1] = __NR_restart_syscall;
586 pt_regs_clear_syscall(regs);
589 /* if there's no signal to deliver, we just put the saved sigmask
592 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
593 clear_thread_flag(TIF_RESTORE_SIGMASK);
594 set_current_blocked(¤t->saved_sigmask);
598 void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0,
599 unsigned long thread_info_flags)
601 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
602 do_signal(regs, orig_i0);
603 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
604 clear_thread_flag(TIF_NOTIFY_RESUME);
605 tracehook_notify_resume(regs);
606 if (current->replacement_session_keyring)
607 key_replace_session_keyring();
612 do_sys_sigstack(struct sigstack __user *ssptr, struct sigstack __user *ossptr,
617 /* First see if old state is wanted. */
619 if (put_user(current->sas_ss_sp + current->sas_ss_size,
620 &ossptr->the_stack) ||
621 __put_user(on_sig_stack(sp), &ossptr->cur_status))
625 /* Now see if we want to update the new state. */
629 if (get_user(ss_sp, &ssptr->the_stack))
631 /* If the current stack was set with sigaltstack, don't
632 swap stacks while we are on it. */
634 if (current->sas_ss_sp && on_sig_stack(sp))
637 /* Since we don't know the extent of the stack, and we don't
638 track onstack-ness, but rather calculate it, we must
639 presume a size. Ho hum this interface is lossy. */
640 current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
641 current->sas_ss_size = SIGSTKSZ;