2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Copyright (C) 1991, 1992 Linus Torvalds
7 * Copyright (C) 1994 - 2000 Ralf Baechle
8 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
10 #include <linux/cache.h>
11 #include <linux/sched.h>
13 #include <linux/personality.h>
14 #include <linux/smp.h>
15 #include <linux/kernel.h>
16 #include <linux/signal.h>
17 #include <linux/errno.h>
18 #include <linux/wait.h>
19 #include <linux/ptrace.h>
20 #include <linux/unistd.h>
21 #include <linux/compiler.h>
22 #include <linux/syscalls.h>
23 #include <linux/uaccess.h>
24 #include <linux/tracehook.h>
28 #include <linux/bitops.h>
29 #include <asm/cacheflush.h>
32 #include <asm/ucontext.h>
33 #include <asm/cpu-features.h>
37 #include "signal-common.h"
39 static int (*save_fp_context)(struct sigcontext __user *sc);
40 static int (*restore_fp_context)(struct sigcontext __user *sc);
42 extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
43 extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
45 extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
46 extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);
49 u32 sf_ass[4]; /* argument save space for o32 */
50 u32 sf_pad[2]; /* Was: signal trampoline */
51 struct sigcontext sf_sc;
56 u32 rs_ass[4]; /* argument save space for o32 */
57 u32 rs_pad[2]; /* Was: signal trampoline */
58 struct siginfo rs_info;
59 struct ucontext rs_uc;
65 static int protected_save_fp_context(struct sigcontext __user *sc)
71 err = save_fp_context(sc); /* this might fail */
75 /* touch the sigcontext and try again */
76 err = __put_user(0, &sc->sc_fpregs[0]) |
77 __put_user(0, &sc->sc_fpregs[31]) |
78 __put_user(0, &sc->sc_fpc_csr);
80 break; /* really bad sigcontext */
85 static int protected_restore_fp_context(struct sigcontext __user *sc)
91 err = restore_fp_context(sc); /* this might fail */
95 /* touch the sigcontext and try again */
96 err = __get_user(tmp, &sc->sc_fpregs[0]) |
97 __get_user(tmp, &sc->sc_fpregs[31]) |
98 __get_user(tmp, &sc->sc_fpc_csr);
100 break; /* really bad sigcontext */
105 int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
109 unsigned int used_math;
111 err |= __put_user(regs->cp0_epc, &sc->sc_pc);
113 err |= __put_user(0, &sc->sc_regs[0]);
114 for (i = 1; i < 32; i++)
115 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
117 #ifdef CONFIG_CPU_HAS_SMARTMIPS
118 err |= __put_user(regs->acx, &sc->sc_acx);
120 err |= __put_user(regs->hi, &sc->sc_mdhi);
121 err |= __put_user(regs->lo, &sc->sc_mdlo);
123 err |= __put_user(mfhi1(), &sc->sc_hi1);
124 err |= __put_user(mflo1(), &sc->sc_lo1);
125 err |= __put_user(mfhi2(), &sc->sc_hi2);
126 err |= __put_user(mflo2(), &sc->sc_lo2);
127 err |= __put_user(mfhi3(), &sc->sc_hi3);
128 err |= __put_user(mflo3(), &sc->sc_lo3);
129 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
132 used_math = !!used_math();
133 err |= __put_user(used_math, &sc->sc_used_math);
137 * Save FPU state to signal context. Signal handler
138 * will "inherit" current FPU state.
140 err |= protected_save_fp_context(sc);
145 int fpcsr_pending(unsigned int __user *fpcsr)
148 unsigned int csr, enabled;
150 err = __get_user(csr, fpcsr);
151 enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
153 * If the signal handler set some FPU exceptions, clear it and
158 err |= __put_user(csr, fpcsr);
165 check_and_restore_fp_context(struct sigcontext __user *sc)
169 err = sig = fpcsr_pending(&sc->sc_fpc_csr);
172 err |= protected_restore_fp_context(sc);
176 int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
178 unsigned int used_math;
183 /* Always make any pending restarted system calls return -EINTR */
184 current_thread_info()->restart_block.fn = do_no_restart_syscall;
186 err |= __get_user(regs->cp0_epc, &sc->sc_pc);
188 #ifdef CONFIG_CPU_HAS_SMARTMIPS
189 err |= __get_user(regs->acx, &sc->sc_acx);
191 err |= __get_user(regs->hi, &sc->sc_mdhi);
192 err |= __get_user(regs->lo, &sc->sc_mdlo);
194 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
195 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
196 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
197 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
198 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
199 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
200 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
203 for (i = 1; i < 32; i++)
204 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
206 err |= __get_user(used_math, &sc->sc_used_math);
207 conditional_used_math(used_math);
210 /* restore fpu context if we have used it before */
212 err = check_and_restore_fp_context(sc);
214 /* signal handler may have used FPU. Give it up. */
221 void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
226 /* Default to using normal stack */
230 * FPU emulator may have it's own trampoline active just
231 * above the user stack, 16-bytes before the next lowest
232 * 16 byte boundary. Try to avoid trashing it.
236 /* This is the X/Open sanctioned signal stack switching. */
237 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
238 sp = current->sas_ss_sp + current->sas_ss_size;
240 return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
244 * Atomically swap in the new signal mask, and wait for a signal.
247 #ifdef CONFIG_TRAD_SIGNALS
248 asmlinkage int sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
251 sigset_t __user *uset;
253 uset = (sigset_t __user *) regs.regs[4];
254 if (copy_from_user(&newset, uset, sizeof(sigset_t)))
256 sigdelsetmask(&newset, ~_BLOCKABLE);
258 spin_lock_irq(¤t->sighand->siglock);
259 current->saved_sigmask = current->blocked;
260 current->blocked = newset;
262 spin_unlock_irq(¤t->sighand->siglock);
264 current->state = TASK_INTERRUPTIBLE;
266 set_thread_flag(TIF_RESTORE_SIGMASK);
267 return -ERESTARTNOHAND;
271 asmlinkage int sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
274 sigset_t __user *unewset;
277 /* XXX Don't preclude handling different sized sigset_t's. */
278 sigsetsize = regs.regs[5];
279 if (sigsetsize != sizeof(sigset_t))
282 unewset = (sigset_t __user *) regs.regs[4];
283 if (copy_from_user(&newset, unewset, sizeof(newset)))
285 sigdelsetmask(&newset, ~_BLOCKABLE);
287 spin_lock_irq(¤t->sighand->siglock);
288 current->saved_sigmask = current->blocked;
289 current->blocked = newset;
291 spin_unlock_irq(¤t->sighand->siglock);
293 current->state = TASK_INTERRUPTIBLE;
295 set_thread_flag(TIF_RESTORE_SIGMASK);
296 return -ERESTARTNOHAND;
299 #ifdef CONFIG_TRAD_SIGNALS
300 SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
301 struct sigaction __user *, oact)
303 struct k_sigaction new_ka, old_ka;
310 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
312 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
313 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
314 err |= __get_user(mask, &act->sa_mask.sig[0]);
318 siginitset(&new_ka.sa.sa_mask, mask);
321 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
324 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
326 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
327 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
328 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
329 err |= __put_user(0, &oact->sa_mask.sig[1]);
330 err |= __put_user(0, &oact->sa_mask.sig[2]);
331 err |= __put_user(0, &oact->sa_mask.sig[3]);
340 asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
342 const stack_t __user *uss = (const stack_t __user *) regs.regs[4];
343 stack_t __user *uoss = (stack_t __user *) regs.regs[5];
344 unsigned long usp = regs.regs[29];
346 return do_sigaltstack(uss, uoss, usp);
349 #ifdef CONFIG_TRAD_SIGNALS
350 asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
352 struct sigframe __user *frame;
356 frame = (struct sigframe __user *) regs.regs[29];
357 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
359 if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
362 sigdelsetmask(&blocked, ~_BLOCKABLE);
363 spin_lock_irq(¤t->sighand->siglock);
364 current->blocked = blocked;
366 spin_unlock_irq(¤t->sighand->siglock);
368 sig = restore_sigcontext(®s, &frame->sf_sc);
372 force_sig(sig, current);
375 * Don't let your children do this ...
377 __asm__ __volatile__(
385 force_sig(SIGSEGV, current);
387 #endif /* CONFIG_TRAD_SIGNALS */
389 asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
391 struct rt_sigframe __user *frame;
396 frame = (struct rt_sigframe __user *) regs.regs[29];
397 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
399 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
402 sigdelsetmask(&set, ~_BLOCKABLE);
403 spin_lock_irq(¤t->sighand->siglock);
404 current->blocked = set;
406 spin_unlock_irq(¤t->sighand->siglock);
408 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext);
412 force_sig(sig, current);
414 if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
416 /* It is more difficult to avoid calling this function than to
417 call it and ignore errors. */
418 do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
421 * Don't let your children do this ...
423 __asm__ __volatile__(
431 force_sig(SIGSEGV, current);
434 #ifdef CONFIG_TRAD_SIGNALS
435 static int setup_frame(void *sig_return, struct k_sigaction *ka,
436 struct pt_regs *regs, int signr, sigset_t *set)
438 struct sigframe __user *frame;
441 frame = get_sigframe(ka, regs, sizeof(*frame));
442 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
445 err |= setup_sigcontext(regs, &frame->sf_sc);
446 err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
451 * Arguments to signal handler:
454 * a1 = 0 (should be cause)
455 * a2 = pointer to struct sigcontext
457 * $25 and c0_epc point to the signal handler, $29 points to the
460 regs->regs[ 4] = signr;
462 regs->regs[ 6] = (unsigned long) &frame->sf_sc;
463 regs->regs[29] = (unsigned long) frame;
464 regs->regs[31] = (unsigned long) sig_return;
465 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
467 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
468 current->comm, current->pid,
469 frame, regs->cp0_epc, regs->regs[31]);
473 force_sigsegv(signr, current);
478 static int setup_rt_frame(void *sig_return, struct k_sigaction *ka,
479 struct pt_regs *regs, int signr, sigset_t *set,
482 struct rt_sigframe __user *frame;
485 frame = get_sigframe(ka, regs, sizeof(*frame));
486 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
489 /* Create siginfo. */
490 err |= copy_siginfo_to_user(&frame->rs_info, info);
492 /* Create the ucontext. */
493 err |= __put_user(0, &frame->rs_uc.uc_flags);
494 err |= __put_user(NULL, &frame->rs_uc.uc_link);
495 err |= __put_user((void __user *)current->sas_ss_sp,
496 &frame->rs_uc.uc_stack.ss_sp);
497 err |= __put_user(sas_ss_flags(regs->regs[29]),
498 &frame->rs_uc.uc_stack.ss_flags);
499 err |= __put_user(current->sas_ss_size,
500 &frame->rs_uc.uc_stack.ss_size);
501 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
502 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
508 * Arguments to signal handler:
511 * a1 = 0 (should be cause)
512 * a2 = pointer to ucontext
514 * $25 and c0_epc point to the signal handler, $29 points to
515 * the struct rt_sigframe.
517 regs->regs[ 4] = signr;
518 regs->regs[ 5] = (unsigned long) &frame->rs_info;
519 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
520 regs->regs[29] = (unsigned long) frame;
521 regs->regs[31] = (unsigned long) sig_return;
522 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
524 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
525 current->comm, current->pid,
526 frame, regs->cp0_epc, regs->regs[31]);
531 force_sigsegv(signr, current);
535 struct mips_abi mips_abi = {
536 #ifdef CONFIG_TRAD_SIGNALS
537 .setup_frame = setup_frame,
538 .signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
540 .setup_rt_frame = setup_rt_frame,
541 .rt_signal_return_offset =
542 offsetof(struct mips_vdso, rt_signal_trampoline),
543 .restart = __NR_restart_syscall
546 static int handle_signal(unsigned long sig, siginfo_t *info,
547 struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
550 struct mips_abi *abi = current->thread.abi;
551 void *vdso = current->mm->context.vdso;
553 switch(regs->regs[0]) {
554 case ERESTART_RESTARTBLOCK:
556 regs->regs[2] = EINTR;
559 if (!(ka->sa.sa_flags & SA_RESTART)) {
560 regs->regs[2] = EINTR;
564 case ERESTARTNOINTR: /* Userland will reload $v0. */
565 regs->regs[7] = regs->regs[26];
569 regs->regs[0] = 0; /* Don't deal with this again. */
571 if (sig_uses_siginfo(ka))
572 ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
573 ka, regs, sig, oldset, info);
575 ret = abi->setup_frame(vdso + abi->signal_return_offset,
576 ka, regs, sig, oldset);
578 spin_lock_irq(¤t->sighand->siglock);
579 sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask);
580 if (!(ka->sa.sa_flags & SA_NODEFER))
581 sigaddset(¤t->blocked, sig);
583 spin_unlock_irq(¤t->sighand->siglock);
588 static void do_signal(struct pt_regs *regs)
590 struct k_sigaction ka;
596 * We want the common case to go fast, which is why we may in certain
597 * cases get here from kernel mode. Just return without doing anything
600 if (!user_mode(regs))
603 if (test_thread_flag(TIF_RESTORE_SIGMASK))
604 oldset = ¤t->saved_sigmask;
606 oldset = ¤t->blocked;
608 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
610 /* Whee! Actually deliver the signal. */
611 if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
613 * A signal was successfully delivered; the saved
614 * sigmask will have been stored in the signal frame,
615 * and will be restored by sigreturn, so we can simply
616 * clear the TIF_RESTORE_SIGMASK flag.
618 if (test_thread_flag(TIF_RESTORE_SIGMASK))
619 clear_thread_flag(TIF_RESTORE_SIGMASK);
626 * Who's code doesn't conform to the restartable syscall convention
627 * dies here!!! The li instruction, a single machine instruction,
628 * must directly be followed by the syscall instruction.
631 if (regs->regs[2] == ERESTARTNOHAND ||
632 regs->regs[2] == ERESTARTSYS ||
633 regs->regs[2] == ERESTARTNOINTR) {
634 regs->regs[7] = regs->regs[26];
637 if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
638 regs->regs[2] = current->thread.abi->restart;
639 regs->regs[7] = regs->regs[26];
642 regs->regs[0] = 0; /* Don't deal with this again. */
646 * If there's no signal to deliver, we just put the saved sigmask
649 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
650 clear_thread_flag(TIF_RESTORE_SIGMASK);
651 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
656 * notification of userspace execution resumption
657 * - triggered by the TIF_WORK_MASK flags
659 asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
660 __u32 thread_info_flags)
662 /* deal with pending signal delivery */
663 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
666 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
667 clear_thread_flag(TIF_NOTIFY_RESUME);
668 tracehook_notify_resume(regs);
669 if (current->replacement_session_keyring)
670 key_replace_session_keyring();
675 static int smp_save_fp_context(struct sigcontext __user *sc)
677 return raw_cpu_has_fpu
678 ? _save_fp_context(sc)
679 : fpu_emulator_save_context(sc);
682 static int smp_restore_fp_context(struct sigcontext __user *sc)
684 return raw_cpu_has_fpu
685 ? _restore_fp_context(sc)
686 : fpu_emulator_restore_context(sc);
690 static int signal_setup(void)
693 /* For now just do the cpu_has_fpu check when the functions are invoked */
694 save_fp_context = smp_save_fp_context;
695 restore_fp_context = smp_restore_fp_context;
698 save_fp_context = _save_fp_context;
699 restore_fp_context = _restore_fp_context;
701 save_fp_context = fpu_emulator_save_context;
702 restore_fp_context = fpu_emulator_restore_context;
709 arch_initcall(signal_setup);