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/smp_lock.h>
16 #include <linux/kernel.h>
17 #include <linux/signal.h>
18 #include <linux/errno.h>
19 #include <linux/wait.h>
20 #include <linux/ptrace.h>
21 #include <linux/unistd.h>
22 #include <linux/compiler.h>
26 #include <linux/bitops.h>
27 #include <asm/cacheflush.h>
30 #include <asm/uaccess.h>
31 #include <asm/ucontext.h>
32 #include <asm/cpu-features.h>
35 #include "signal-common.h"
39 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
41 #if ICACHE_REFILLS_WORKAROUND_WAR == 0
44 u32 rs_ass[4]; /* argument save space for o32 */
45 u32 rs_code[2]; /* signal trampoline */
46 struct siginfo rs_info;
47 struct ucontext rs_uc;
53 u32 rs_ass[4]; /* argument save space for o32 */
55 struct siginfo rs_info;
56 struct ucontext rs_uc;
57 u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */
65 int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
70 err |= __put_user(regs->cp0_epc, &sc->sc_pc);
72 err |= __put_user(0, &sc->sc_regs[0]);
73 for (i = 1; i < 32; i++)
74 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
76 err |= __put_user(regs->hi, &sc->sc_mdhi);
77 err |= __put_user(regs->lo, &sc->sc_mdlo);
79 err |= __put_user(mfhi1(), &sc->sc_hi1);
80 err |= __put_user(mflo1(), &sc->sc_lo1);
81 err |= __put_user(mfhi2(), &sc->sc_hi2);
82 err |= __put_user(mflo2(), &sc->sc_lo2);
83 err |= __put_user(mfhi3(), &sc->sc_hi3);
84 err |= __put_user(mflo3(), &sc->sc_lo3);
85 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
88 err |= __put_user(!!used_math(), &sc->sc_used_math);
92 * Save FPU state to signal context. Signal handler
93 * will "inherit" current FPU state.
97 if (!is_fpu_owner()) {
101 err |= save_fp_context(sc);
108 int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
110 unsigned int used_math;
115 /* Always make any pending restarted system calls return -EINTR */
116 current_thread_info()->restart_block.fn = do_no_restart_syscall;
118 err |= __get_user(regs->cp0_epc, &sc->sc_pc);
119 err |= __get_user(regs->hi, &sc->sc_mdhi);
120 err |= __get_user(regs->lo, &sc->sc_mdlo);
122 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
123 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
124 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
125 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
126 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
127 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
128 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
131 for (i = 1; i < 32; i++)
132 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
134 err |= __get_user(used_math, &sc->sc_used_math);
135 conditional_used_math(used_math);
140 /* restore fpu context if we have used it before */
142 err |= restore_fp_context(sc);
144 /* signal handler may have used FPU. Give it up. */
153 void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
158 /* Default to using normal stack */
162 * FPU emulator may have it's own trampoline active just
163 * above the user stack, 16-bytes before the next lowest
164 * 16 byte boundary. Try to avoid trashing it.
168 /* This is the X/Open sanctioned signal stack switching. */
169 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
170 sp = current->sas_ss_sp + current->sas_ss_size;
172 return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
175 int install_sigtramp(unsigned int __user *tramp, unsigned int syscall)
180 * Set up the return code ...
182 * li v0, __NR__foo_sigreturn
186 err = __put_user(0x24020000 + syscall, tramp + 0);
187 err |= __put_user(0x0000000c , tramp + 1);
188 if (ICACHE_REFILLS_WORKAROUND_WAR) {
189 err |= __put_user(0, tramp + 2);
190 err |= __put_user(0, tramp + 3);
191 err |= __put_user(0, tramp + 4);
192 err |= __put_user(0, tramp + 5);
193 err |= __put_user(0, tramp + 6);
194 err |= __put_user(0, tramp + 7);
196 flush_cache_sigtramp((unsigned long) tramp);
202 * Atomically swap in the new signal mask, and wait for a signal.
205 #ifdef CONFIG_TRAD_SIGNALS
206 save_static_function(sys_sigsuspend);
207 __attribute_used__ noinline static int
208 _sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
211 sigset_t __user *uset;
213 uset = (sigset_t __user *) regs.regs[4];
214 if (copy_from_user(&newset, uset, sizeof(sigset_t)))
216 sigdelsetmask(&newset, ~_BLOCKABLE);
218 spin_lock_irq(¤t->sighand->siglock);
219 current->saved_sigmask = current->blocked;
220 current->blocked = newset;
222 spin_unlock_irq(¤t->sighand->siglock);
224 current->state = TASK_INTERRUPTIBLE;
226 set_thread_flag(TIF_RESTORE_SIGMASK);
227 return -ERESTARTNOHAND;
231 save_static_function(sys_rt_sigsuspend);
232 __attribute_used__ noinline static int
233 _sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
236 sigset_t __user *unewset;
239 /* XXX Don't preclude handling different sized sigset_t's. */
240 sigsetsize = regs.regs[5];
241 if (sigsetsize != sizeof(sigset_t))
244 unewset = (sigset_t __user *) regs.regs[4];
245 if (copy_from_user(&newset, unewset, sizeof(newset)))
247 sigdelsetmask(&newset, ~_BLOCKABLE);
249 spin_lock_irq(¤t->sighand->siglock);
250 current->saved_sigmask = current->blocked;
251 current->blocked = newset;
253 spin_unlock_irq(¤t->sighand->siglock);
255 current->state = TASK_INTERRUPTIBLE;
257 set_thread_flag(TIF_RESTORE_SIGMASK);
258 return -ERESTARTNOHAND;
261 #ifdef CONFIG_TRAD_SIGNALS
262 asmlinkage int sys_sigaction(int sig, const struct sigaction __user *act,
263 struct sigaction __user *oact)
265 struct k_sigaction new_ka, old_ka;
272 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
274 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
275 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
276 err |= __get_user(mask, &act->sa_mask.sig[0]);
280 siginitset(&new_ka.sa.sa_mask, mask);
283 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
286 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
288 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
289 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
290 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
291 err |= __put_user(0, &oact->sa_mask.sig[1]);
292 err |= __put_user(0, &oact->sa_mask.sig[2]);
293 err |= __put_user(0, &oact->sa_mask.sig[3]);
302 asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
304 const stack_t __user *uss = (const stack_t __user *) regs.regs[4];
305 stack_t __user *uoss = (stack_t __user *) regs.regs[5];
306 unsigned long usp = regs.regs[29];
308 return do_sigaltstack(uss, uoss, usp);
311 #ifdef CONFIG_TRAD_SIGNALS
312 save_static_function(sys_sigreturn);
313 __attribute_used__ noinline static void
314 _sys_sigreturn(nabi_no_regargs struct pt_regs regs)
316 struct sigframe __user *frame;
319 frame = (struct sigframe __user *) regs.regs[29];
320 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
322 if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
325 sigdelsetmask(&blocked, ~_BLOCKABLE);
326 spin_lock_irq(¤t->sighand->siglock);
327 current->blocked = blocked;
329 spin_unlock_irq(¤t->sighand->siglock);
331 if (restore_sigcontext(®s, &frame->sf_sc))
335 * Don't let your children do this ...
337 __asm__ __volatile__(
345 force_sig(SIGSEGV, current);
347 #endif /* CONFIG_TRAD_SIGNALS */
349 save_static_function(sys_rt_sigreturn);
350 __attribute_used__ noinline static void
351 _sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
353 struct rt_sigframe __user *frame;
357 frame = (struct rt_sigframe __user *) regs.regs[29];
358 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
360 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
363 sigdelsetmask(&set, ~_BLOCKABLE);
364 spin_lock_irq(¤t->sighand->siglock);
365 current->blocked = set;
367 spin_unlock_irq(¤t->sighand->siglock);
369 if (restore_sigcontext(®s, &frame->rs_uc.uc_mcontext))
372 if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
374 /* It is more difficult to avoid calling this function than to
375 call it and ignore errors. */
376 do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
379 * Don't let your children do this ...
381 __asm__ __volatile__(
389 force_sig(SIGSEGV, current);
392 #ifdef CONFIG_TRAD_SIGNALS
393 int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
394 int signr, sigset_t *set)
396 struct sigframe __user *frame;
399 frame = get_sigframe(ka, regs, sizeof(*frame));
400 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
403 install_sigtramp(frame->sf_code, __NR_sigreturn);
405 err |= setup_sigcontext(regs, &frame->sf_sc);
406 err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
411 * Arguments to signal handler:
414 * a1 = 0 (should be cause)
415 * a2 = pointer to struct sigcontext
417 * $25 and c0_epc point to the signal handler, $29 points to the
420 regs->regs[ 4] = signr;
422 regs->regs[ 6] = (unsigned long) &frame->sf_sc;
423 regs->regs[29] = (unsigned long) frame;
424 regs->regs[31] = (unsigned long) frame->sf_code;
425 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
428 printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
429 current->comm, current->pid,
430 frame, regs->cp0_epc, frame->regs[31]);
435 force_sigsegv(signr, current);
440 int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
441 int signr, sigset_t *set, siginfo_t *info)
443 struct rt_sigframe __user *frame;
446 frame = get_sigframe(ka, regs, sizeof(*frame));
447 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
450 install_sigtramp(frame->rs_code, __NR_rt_sigreturn);
452 /* Create siginfo. */
453 err |= copy_siginfo_to_user(&frame->rs_info, info);
455 /* Create the ucontext. */
456 err |= __put_user(0, &frame->rs_uc.uc_flags);
457 err |= __put_user(NULL, &frame->rs_uc.uc_link);
458 err |= __put_user((void __user *)current->sas_ss_sp,
459 &frame->rs_uc.uc_stack.ss_sp);
460 err |= __put_user(sas_ss_flags(regs->regs[29]),
461 &frame->rs_uc.uc_stack.ss_flags);
462 err |= __put_user(current->sas_ss_size,
463 &frame->rs_uc.uc_stack.ss_size);
464 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
465 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
471 * Arguments to signal handler:
474 * a1 = 0 (should be cause)
475 * a2 = pointer to ucontext
477 * $25 and c0_epc point to the signal handler, $29 points to
478 * the struct rt_sigframe.
480 regs->regs[ 4] = signr;
481 regs->regs[ 5] = (unsigned long) &frame->rs_info;
482 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
483 regs->regs[29] = (unsigned long) frame;
484 regs->regs[31] = (unsigned long) frame->rs_code;
485 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
488 printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
489 current->comm, current->pid,
490 frame, regs->cp0_epc, regs->regs[31]);
495 force_sigsegv(signr, current);
499 static inline int handle_signal(unsigned long sig, siginfo_t *info,
500 struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
504 switch(regs->regs[0]) {
505 case ERESTART_RESTARTBLOCK:
507 regs->regs[2] = EINTR;
510 if (!(ka->sa.sa_flags & SA_RESTART)) {
511 regs->regs[2] = EINTR;
515 case ERESTARTNOINTR: /* Userland will reload $v0. */
516 regs->regs[7] = regs->regs[26];
520 regs->regs[0] = 0; /* Don't deal with this again. */
522 if (sig_uses_siginfo(ka))
523 ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
525 ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);
527 spin_lock_irq(¤t->sighand->siglock);
528 sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
529 if (!(ka->sa.sa_flags & SA_NODEFER))
530 sigaddset(¤t->blocked,sig);
532 spin_unlock_irq(¤t->sighand->siglock);
537 void do_signal(struct pt_regs *regs)
539 struct k_sigaction ka;
545 * We want the common case to go fast, which is why we may in certain
546 * cases get here from kernel mode. Just return without doing anything
549 if (!user_mode(regs))
552 if (test_thread_flag(TIF_RESTORE_SIGMASK))
553 oldset = ¤t->saved_sigmask;
555 oldset = ¤t->blocked;
557 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
559 /* Whee! Actually deliver the signal. */
560 if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
562 * A signal was successfully delivered; the saved
563 * sigmask will have been stored in the signal frame,
564 * and will be restored by sigreturn, so we can simply
565 * clear the TIF_RESTORE_SIGMASK flag.
567 if (test_thread_flag(TIF_RESTORE_SIGMASK))
568 clear_thread_flag(TIF_RESTORE_SIGMASK);
575 * Who's code doesn't conform to the restartable syscall convention
576 * dies here!!! The li instruction, a single machine instruction,
577 * must directly be followed by the syscall instruction.
580 if (regs->regs[2] == ERESTARTNOHAND ||
581 regs->regs[2] == ERESTARTSYS ||
582 regs->regs[2] == ERESTARTNOINTR) {
583 regs->regs[7] = regs->regs[26];
586 if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
587 regs->regs[2] = __NR_restart_syscall;
588 regs->regs[7] = regs->regs[26];
591 regs->regs[0] = 0; /* Don't deal with this again. */
595 * If there's no signal to deliver, we just put the saved sigmask
598 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
599 clear_thread_flag(TIF_RESTORE_SIGMASK);
600 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
605 * notification of userspace execution resumption
606 * - triggered by the TIF_WORK_MASK flags
608 asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
609 __u32 thread_info_flags)
611 /* deal with pending signal delivery */
612 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
613 current->thread.abi->do_signal(regs);