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>
36 #include "signal-common.h"
39 * Horribly complicated - with the bloody RM9000 workarounds enabled
40 * the signal trampolines is moving to the end of the structure so we can
41 * increase the alignment without breaking software compatibility.
43 #if ICACHE_REFILLS_WORKAROUND_WAR == 0
46 u32 sf_ass[4]; /* argument save space for o32 */
47 u32 sf_code[2]; /* signal trampoline */
48 struct sigcontext sf_sc;
53 u32 rs_ass[4]; /* argument save space for o32 */
54 u32 rs_code[2]; /* signal trampoline */
55 struct siginfo rs_info;
56 struct ucontext rs_uc;
62 u32 sf_ass[4]; /* argument save space for o32 */
64 struct sigcontext sf_sc; /* hw context */
66 u32 sf_code[8] ____cacheline_aligned; /* signal trampoline */
70 u32 rs_ass[4]; /* argument save space for o32 */
72 struct siginfo rs_info;
73 struct ucontext rs_uc;
74 u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */
82 static int protected_save_fp_context(struct sigcontext __user *sc)
88 err = save_fp_context(sc); /* this might fail */
92 /* touch the sigcontext and try again */
93 err = __put_user(0, &sc->sc_fpregs[0]) |
94 __put_user(0, &sc->sc_fpregs[31]) |
95 __put_user(0, &sc->sc_fpc_csr);
97 break; /* really bad sigcontext */
102 static int protected_restore_fp_context(struct sigcontext __user *sc)
108 err = restore_fp_context(sc); /* this might fail */
112 /* touch the sigcontext and try again */
113 err = __get_user(tmp, &sc->sc_fpregs[0]) |
114 __get_user(tmp, &sc->sc_fpregs[31]) |
115 __get_user(tmp, &sc->sc_fpc_csr);
117 break; /* really bad sigcontext */
122 int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
126 unsigned int used_math;
128 err |= __put_user(regs->cp0_epc, &sc->sc_pc);
130 err |= __put_user(0, &sc->sc_regs[0]);
131 for (i = 1; i < 32; i++)
132 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
134 #ifdef CONFIG_CPU_HAS_SMARTMIPS
135 err |= __put_user(regs->acx, &sc->sc_acx);
137 err |= __put_user(regs->hi, &sc->sc_mdhi);
138 err |= __put_user(regs->lo, &sc->sc_mdlo);
140 err |= __put_user(mfhi1(), &sc->sc_hi1);
141 err |= __put_user(mflo1(), &sc->sc_lo1);
142 err |= __put_user(mfhi2(), &sc->sc_hi2);
143 err |= __put_user(mflo2(), &sc->sc_lo2);
144 err |= __put_user(mfhi3(), &sc->sc_hi3);
145 err |= __put_user(mflo3(), &sc->sc_lo3);
146 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
149 used_math = !!used_math();
150 err |= __put_user(used_math, &sc->sc_used_math);
154 * Save FPU state to signal context. Signal handler
155 * will "inherit" current FPU state.
157 err |= protected_save_fp_context(sc);
162 int fpcsr_pending(unsigned int __user *fpcsr)
165 unsigned int csr, enabled;
167 err = __get_user(csr, fpcsr);
168 enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
170 * If the signal handler set some FPU exceptions, clear it and
175 err |= __put_user(csr, fpcsr);
182 check_and_restore_fp_context(struct sigcontext __user *sc)
186 err = sig = fpcsr_pending(&sc->sc_fpc_csr);
189 err |= protected_restore_fp_context(sc);
193 int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
195 unsigned int used_math;
200 /* Always make any pending restarted system calls return -EINTR */
201 current_thread_info()->restart_block.fn = do_no_restart_syscall;
203 err |= __get_user(regs->cp0_epc, &sc->sc_pc);
205 #ifdef CONFIG_CPU_HAS_SMARTMIPS
206 err |= __get_user(regs->acx, &sc->sc_acx);
208 err |= __get_user(regs->hi, &sc->sc_mdhi);
209 err |= __get_user(regs->lo, &sc->sc_mdlo);
211 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
212 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
213 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
214 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
215 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
216 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
217 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
220 for (i = 1; i < 32; i++)
221 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
223 err |= __get_user(used_math, &sc->sc_used_math);
224 conditional_used_math(used_math);
227 /* restore fpu context if we have used it before */
229 err = check_and_restore_fp_context(sc);
231 /* signal handler may have used FPU. Give it up. */
238 void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
243 /* Default to using normal stack */
247 * FPU emulator may have it's own trampoline active just
248 * above the user stack, 16-bytes before the next lowest
249 * 16 byte boundary. Try to avoid trashing it.
253 /* This is the X/Open sanctioned signal stack switching. */
254 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
255 sp = current->sas_ss_sp + current->sas_ss_size;
257 return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
260 int install_sigtramp(unsigned int __user *tramp, unsigned int syscall)
265 * Set up the return code ...
267 * li v0, __NR__foo_sigreturn
271 err = __put_user(0x24020000 + syscall, tramp + 0);
272 err |= __put_user(0x0000000c , tramp + 1);
273 if (ICACHE_REFILLS_WORKAROUND_WAR) {
274 err |= __put_user(0, tramp + 2);
275 err |= __put_user(0, tramp + 3);
276 err |= __put_user(0, tramp + 4);
277 err |= __put_user(0, tramp + 5);
278 err |= __put_user(0, tramp + 6);
279 err |= __put_user(0, tramp + 7);
281 flush_cache_sigtramp((unsigned long) tramp);
287 * Atomically swap in the new signal mask, and wait for a signal.
290 #ifdef CONFIG_TRAD_SIGNALS
291 asmlinkage int sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
294 sigset_t __user *uset;
296 uset = (sigset_t __user *) regs.regs[4];
297 if (copy_from_user(&newset, uset, sizeof(sigset_t)))
299 sigdelsetmask(&newset, ~_BLOCKABLE);
301 spin_lock_irq(¤t->sighand->siglock);
302 current->saved_sigmask = current->blocked;
303 current->blocked = newset;
305 spin_unlock_irq(¤t->sighand->siglock);
307 current->state = TASK_INTERRUPTIBLE;
309 set_thread_flag(TIF_RESTORE_SIGMASK);
310 return -ERESTARTNOHAND;
314 asmlinkage int sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
317 sigset_t __user *unewset;
320 /* XXX Don't preclude handling different sized sigset_t's. */
321 sigsetsize = regs.regs[5];
322 if (sigsetsize != sizeof(sigset_t))
325 unewset = (sigset_t __user *) regs.regs[4];
326 if (copy_from_user(&newset, unewset, sizeof(newset)))
328 sigdelsetmask(&newset, ~_BLOCKABLE);
330 spin_lock_irq(¤t->sighand->siglock);
331 current->saved_sigmask = current->blocked;
332 current->blocked = newset;
334 spin_unlock_irq(¤t->sighand->siglock);
336 current->state = TASK_INTERRUPTIBLE;
338 set_thread_flag(TIF_RESTORE_SIGMASK);
339 return -ERESTARTNOHAND;
342 #ifdef CONFIG_TRAD_SIGNALS
343 SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
344 struct sigaction __user *, oact)
346 struct k_sigaction new_ka, old_ka;
353 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
355 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
356 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
357 err |= __get_user(mask, &act->sa_mask.sig[0]);
361 siginitset(&new_ka.sa.sa_mask, mask);
364 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
367 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
369 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
370 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
371 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
372 err |= __put_user(0, &oact->sa_mask.sig[1]);
373 err |= __put_user(0, &oact->sa_mask.sig[2]);
374 err |= __put_user(0, &oact->sa_mask.sig[3]);
383 asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
385 const stack_t __user *uss = (const stack_t __user *) regs.regs[4];
386 stack_t __user *uoss = (stack_t __user *) regs.regs[5];
387 unsigned long usp = regs.regs[29];
389 return do_sigaltstack(uss, uoss, usp);
392 #ifdef CONFIG_TRAD_SIGNALS
393 asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
395 struct sigframe __user *frame;
399 frame = (struct sigframe __user *) regs.regs[29];
400 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
402 if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
405 sigdelsetmask(&blocked, ~_BLOCKABLE);
406 spin_lock_irq(¤t->sighand->siglock);
407 current->blocked = blocked;
409 spin_unlock_irq(¤t->sighand->siglock);
411 sig = restore_sigcontext(®s, &frame->sf_sc);
415 force_sig(sig, current);
418 * Don't let your children do this ...
420 __asm__ __volatile__(
428 force_sig(SIGSEGV, current);
430 #endif /* CONFIG_TRAD_SIGNALS */
432 asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
434 struct rt_sigframe __user *frame;
439 frame = (struct rt_sigframe __user *) regs.regs[29];
440 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
442 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
445 sigdelsetmask(&set, ~_BLOCKABLE);
446 spin_lock_irq(¤t->sighand->siglock);
447 current->blocked = set;
449 spin_unlock_irq(¤t->sighand->siglock);
451 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext);
455 force_sig(sig, current);
457 if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
459 /* It is more difficult to avoid calling this function than to
460 call it and ignore errors. */
461 do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
464 * Don't let your children do this ...
466 __asm__ __volatile__(
474 force_sig(SIGSEGV, current);
477 #ifdef CONFIG_TRAD_SIGNALS
478 static int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
479 int signr, sigset_t *set)
481 struct sigframe __user *frame;
484 frame = get_sigframe(ka, regs, sizeof(*frame));
485 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
488 err |= install_sigtramp(frame->sf_code, __NR_sigreturn);
490 err |= setup_sigcontext(regs, &frame->sf_sc);
491 err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
496 * Arguments to signal handler:
499 * a1 = 0 (should be cause)
500 * a2 = pointer to struct sigcontext
502 * $25 and c0_epc point to the signal handler, $29 points to the
505 regs->regs[ 4] = signr;
507 regs->regs[ 6] = (unsigned long) &frame->sf_sc;
508 regs->regs[29] = (unsigned long) frame;
509 regs->regs[31] = (unsigned long) frame->sf_code;
510 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
512 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
513 current->comm, current->pid,
514 frame, regs->cp0_epc, regs->regs[31]);
518 force_sigsegv(signr, current);
523 static int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
524 int signr, sigset_t *set, siginfo_t *info)
526 struct rt_sigframe __user *frame;
529 frame = get_sigframe(ka, regs, sizeof(*frame));
530 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
533 err |= install_sigtramp(frame->rs_code, __NR_rt_sigreturn);
535 /* Create siginfo. */
536 err |= copy_siginfo_to_user(&frame->rs_info, info);
538 /* Create the ucontext. */
539 err |= __put_user(0, &frame->rs_uc.uc_flags);
540 err |= __put_user(NULL, &frame->rs_uc.uc_link);
541 err |= __put_user((void __user *)current->sas_ss_sp,
542 &frame->rs_uc.uc_stack.ss_sp);
543 err |= __put_user(sas_ss_flags(regs->regs[29]),
544 &frame->rs_uc.uc_stack.ss_flags);
545 err |= __put_user(current->sas_ss_size,
546 &frame->rs_uc.uc_stack.ss_size);
547 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
548 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
554 * Arguments to signal handler:
557 * a1 = 0 (should be cause)
558 * a2 = pointer to ucontext
560 * $25 and c0_epc point to the signal handler, $29 points to
561 * the struct rt_sigframe.
563 regs->regs[ 4] = signr;
564 regs->regs[ 5] = (unsigned long) &frame->rs_info;
565 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
566 regs->regs[29] = (unsigned long) frame;
567 regs->regs[31] = (unsigned long) frame->rs_code;
568 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
570 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
571 current->comm, current->pid,
572 frame, regs->cp0_epc, regs->regs[31]);
577 force_sigsegv(signr, current);
581 struct mips_abi mips_abi = {
582 #ifdef CONFIG_TRAD_SIGNALS
583 .setup_frame = setup_frame,
585 .setup_rt_frame = setup_rt_frame,
586 .restart = __NR_restart_syscall
589 static int handle_signal(unsigned long sig, siginfo_t *info,
590 struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
594 switch(regs->regs[0]) {
595 case ERESTART_RESTARTBLOCK:
597 regs->regs[2] = EINTR;
600 if (!(ka->sa.sa_flags & SA_RESTART)) {
601 regs->regs[2] = EINTR;
605 case ERESTARTNOINTR: /* Userland will reload $v0. */
606 regs->regs[7] = regs->regs[26];
610 regs->regs[0] = 0; /* Don't deal with this again. */
612 if (sig_uses_siginfo(ka))
613 ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
615 ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);
617 spin_lock_irq(¤t->sighand->siglock);
618 sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask);
619 if (!(ka->sa.sa_flags & SA_NODEFER))
620 sigaddset(¤t->blocked, sig);
622 spin_unlock_irq(¤t->sighand->siglock);
627 static void do_signal(struct pt_regs *regs)
629 struct k_sigaction ka;
635 * We want the common case to go fast, which is why we may in certain
636 * cases get here from kernel mode. Just return without doing anything
639 if (!user_mode(regs))
642 if (test_thread_flag(TIF_RESTORE_SIGMASK))
643 oldset = ¤t->saved_sigmask;
645 oldset = ¤t->blocked;
647 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
649 /* Whee! Actually deliver the signal. */
650 if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
652 * A signal was successfully delivered; the saved
653 * sigmask will have been stored in the signal frame,
654 * and will be restored by sigreturn, so we can simply
655 * clear the TIF_RESTORE_SIGMASK flag.
657 if (test_thread_flag(TIF_RESTORE_SIGMASK))
658 clear_thread_flag(TIF_RESTORE_SIGMASK);
665 * Who's code doesn't conform to the restartable syscall convention
666 * dies here!!! The li instruction, a single machine instruction,
667 * must directly be followed by the syscall instruction.
670 if (regs->regs[2] == ERESTARTNOHAND ||
671 regs->regs[2] == ERESTARTSYS ||
672 regs->regs[2] == ERESTARTNOINTR) {
673 regs->regs[7] = regs->regs[26];
676 if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
677 regs->regs[2] = current->thread.abi->restart;
678 regs->regs[7] = regs->regs[26];
681 regs->regs[0] = 0; /* Don't deal with this again. */
685 * If there's no signal to deliver, we just put the saved sigmask
688 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
689 clear_thread_flag(TIF_RESTORE_SIGMASK);
690 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
695 * notification of userspace execution resumption
696 * - triggered by the TIF_WORK_MASK flags
698 asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
699 __u32 thread_info_flags)
701 /* deal with pending signal delivery */
702 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
705 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
706 clear_thread_flag(TIF_NOTIFY_RESUME);
707 tracehook_notify_resume(regs);
708 if (current->replacement_session_keyring)
709 key_replace_session_keyring();