4 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
5 * Copyright (C) 2008-2009 PetaLogix
6 * Copyright (C) 2003,2004 John Williams <jwilliams@itee.uq.edu.au>
7 * Copyright (C) 2001 NEC Corporation
8 * Copyright (C) 2001 Miles Bader <miles@gnu.org>
9 * Copyright (C) 1999,2000 Niibe Yutaka & Kaz Kojima
10 * Copyright (C) 1991,1992 Linus Torvalds
12 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
14 * This file was was derived from the sh version, arch/sh/kernel/signal.c
16 * This file is subject to the terms and conditions of the GNU General
17 * Public License. See the file COPYING in the main directory of this
18 * archive for more details.
21 #include <linux/sched.h>
23 #include <linux/smp.h>
24 #include <linux/smp_lock.h>
25 #include <linux/kernel.h>
26 #include <linux/signal.h>
27 #include <linux/errno.h>
28 #include <linux/wait.h>
29 #include <linux/ptrace.h>
30 #include <linux/unistd.h>
31 #include <linux/stddef.h>
32 #include <linux/personality.h>
33 #include <linux/percpu.h>
34 #include <linux/linkage.h>
35 #include <asm/entry.h>
36 #include <asm/ucontext.h>
37 #include <linux/uaccess.h>
38 #include <asm/pgtable.h>
39 #include <asm/pgalloc.h>
40 #include <linux/syscalls.h>
41 #include <asm/cacheflush.h>
42 #include <asm/syscalls.h>
44 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
46 asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset, int in_sycall);
49 * Atomically swap in the new signal mask, and wait for a signal.
52 sys_sigsuspend(old_sigset_t mask, struct pt_regs *regs)
57 spin_lock_irq(¤t->sighand->siglock);
58 saveset = current->blocked;
59 siginitset(¤t->blocked, mask);
61 spin_unlock_irq(¤t->sighand->siglock);
65 current->state = TASK_INTERRUPTIBLE;
67 if (do_signal(regs, &saveset, 1))
73 sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize,
76 sigset_t saveset, newset;
78 /* XXX: Don't preclude handling different sized sigset_t's. */
79 if (sigsetsize != sizeof(sigset_t))
82 if (copy_from_user(&newset, unewset, sizeof(newset)))
84 sigdelsetmask(&newset, ~_BLOCKABLE);
85 spin_lock_irq(¤t->sighand->siglock);
86 saveset = current->blocked;
87 current->blocked = newset;
89 spin_unlock_irq(¤t->sighand->siglock);
93 current->state = TASK_INTERRUPTIBLE;
95 if (do_signal(regs, &saveset, 1))
101 sys_sigaction(int sig, const struct old_sigaction *act,
102 struct old_sigaction *oact)
104 struct k_sigaction new_ka, old_ka;
109 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
110 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
111 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
113 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
114 __get_user(mask, &act->sa_mask);
115 siginitset(&new_ka.sa.sa_mask, mask);
118 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
121 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
122 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
123 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
125 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
126 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
133 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
134 struct pt_regs *regs)
136 return do_sigaltstack(uss, uoss, regs->r1);
140 * Do a signal return; undo the signal stack.
144 struct sigcontext sc;
145 unsigned long extramask[_NSIG_WORDS-1];
146 unsigned long tramp[2]; /* signal trampoline */
152 unsigned long tramp[2]; /* signal trampoline */
156 restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc, int *rval_p)
158 unsigned int err = 0;
160 #define COPY(x) {err |= __get_user(regs->x, &sc->regs.x); }
163 COPY(r2); COPY(r3); COPY(r4); COPY(r5);
164 COPY(r6); COPY(r7); COPY(r8); COPY(r9);
165 COPY(r10); COPY(r11); COPY(r12); COPY(r13);
166 COPY(r14); COPY(r15); COPY(r16); COPY(r17);
167 COPY(r18); COPY(r19); COPY(r20); COPY(r21);
168 COPY(r22); COPY(r23); COPY(r24); COPY(r25);
169 COPY(r26); COPY(r27); COPY(r28); COPY(r29);
170 COPY(r30); COPY(r31);
171 COPY(pc); COPY(ear); COPY(esr); COPY(fsr);
179 asmlinkage int sys_sigreturn(struct pt_regs *regs)
181 struct sigframe *frame = (struct sigframe *)regs->r1;
185 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
188 if (__get_user(set.sig[0], &frame->sc.oldmask)
190 && __copy_from_user(&set.sig[1], &frame->extramask,
191 sizeof(frame->extramask))))
194 sigdelsetmask(&set, ~_BLOCKABLE);
196 spin_lock_irq(¤t->sighand->siglock);
197 current->blocked = set;
199 spin_unlock_irq(¤t->sighand->siglock);
201 if (restore_sigcontext(regs, &frame->sc, &rval))
206 force_sig(SIGSEGV, current);
210 asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
212 struct rt_sigframe *frame = (struct rt_sigframe *)regs->r1;
217 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
220 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
223 sigdelsetmask(&set, ~_BLOCKABLE);
224 spin_lock_irq(¤t->sighand->siglock);
225 current->blocked = set;
227 spin_unlock_irq(¤t->sighand->siglock);
229 if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &rval))
232 if (__copy_from_user((void *)&st, &frame->uc.uc_stack, sizeof(st)))
234 /* It is more difficult to avoid calling this function than to
235 call it and ignore errors. */
236 do_sigaltstack(&st, NULL, regs->r1);
241 force_sig(SIGSEGV, current);
246 * Set up a signal frame.
250 setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
255 #define COPY(x) {err |= __put_user(regs->x, &sc->regs.x); }
258 COPY(r2); COPY(r3); COPY(r4); COPY(r5);
259 COPY(r6); COPY(r7); COPY(r8); COPY(r9);
260 COPY(r10); COPY(r11); COPY(r12); COPY(r13);
261 COPY(r14); COPY(r15); COPY(r16); COPY(r17);
262 COPY(r18); COPY(r19); COPY(r20); COPY(r21);
263 COPY(r22); COPY(r23); COPY(r24); COPY(r25);
264 COPY(r26); COPY(r27); COPY(r28); COPY(r29);
265 COPY(r30); COPY(r31);
266 COPY(pc); COPY(ear); COPY(esr); COPY(fsr);
269 err |= __put_user(mask, &sc->oldmask);
275 * Determine which stack to use..
278 get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
280 /* Default to using normal stack */
281 unsigned long sp = regs->r1;
283 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && !on_sig_stack(sp))
284 sp = current->sas_ss_sp + current->sas_ss_size;
286 return (void *)((sp - frame_size) & -8UL);
289 static void setup_frame(int sig, struct k_sigaction *ka,
290 sigset_t *set, struct pt_regs *regs)
292 struct sigframe *frame;
296 frame = get_sigframe(ka, regs, sizeof(*frame));
298 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
301 signal = current_thread_info()->exec_domain
302 && current_thread_info()->exec_domain->signal_invmap
304 ? current_thread_info()->exec_domain->signal_invmap[sig]
307 err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
309 if (_NSIG_WORDS > 1) {
310 err |= __copy_to_user(frame->extramask, &set->sig[1],
311 sizeof(frame->extramask));
314 /* Set up to return from userspace. If provided, use a stub
315 already in userspace. */
316 /* minus 8 is offset to cater for "rtsd r15,8" offset */
317 if (ka->sa.sa_flags & SA_RESTORER) {
318 regs->r15 = ((unsigned long)ka->sa.sa_restorer)-8;
320 /* Note, these encodings are _big endian_! */
322 /* addi r12, r0, __NR_sigreturn */
323 err |= __put_user(0x31800000 | __NR_sigreturn ,
326 err |= __put_user(0xb9cc0008, frame->tramp + 1);
328 /* Return from sighandler will jump to the tramp.
329 Negative 8 offset because return is rtsd r15, 8 */
330 regs->r15 = ((unsigned long)frame->tramp)-8;
332 __invalidate_cache_sigtramp((unsigned long)frame->tramp);
338 /* Set up registers for signal handler */
339 regs->r1 = (unsigned long) frame;
340 /* Signal handler args: */
341 regs->r5 = signal; /* Arg 0: signum */
342 regs->r6 = (unsigned long) &frame->sc; /* arg 1: sigcontext */
344 /* Offset of 4 to handle microblaze rtid r14, 0 */
345 regs->pc = (unsigned long)ka->sa.sa_handler;
350 printk(KERN_INFO "SIG deliver (%s:%d): sp=%p pc=%08lx\n",
351 current->comm, current->pid, frame, regs->pc);
358 ka->sa.sa_handler = SIG_DFL;
359 force_sig(SIGSEGV, current);
362 static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
363 sigset_t *set, struct pt_regs *regs)
365 struct rt_sigframe *frame;
369 frame = get_sigframe(ka, regs, sizeof(*frame));
371 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
374 signal = current_thread_info()->exec_domain
375 && current_thread_info()->exec_domain->signal_invmap
377 ? current_thread_info()->exec_domain->signal_invmap[sig]
380 err |= copy_siginfo_to_user(&frame->info, info);
382 /* Create the ucontext. */
383 err |= __put_user(0, &frame->uc.uc_flags);
384 err |= __put_user(0, &frame->uc.uc_link);
385 err |= __put_user((void *)current->sas_ss_sp,
386 &frame->uc.uc_stack.ss_sp);
387 err |= __put_user(sas_ss_flags(regs->r1),
388 &frame->uc.uc_stack.ss_flags);
389 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
390 err |= setup_sigcontext(&frame->uc.uc_mcontext,
392 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
394 /* Set up to return from userspace. If provided, use a stub
395 already in userspace. */
396 /* minus 8 is offset to cater for "rtsd r15,8" */
397 if (ka->sa.sa_flags & SA_RESTORER) {
398 regs->r15 = ((unsigned long)ka->sa.sa_restorer)-8;
400 /* addi r12, r0, __NR_sigreturn */
401 err |= __put_user(0x31800000 | __NR_rt_sigreturn ,
404 err |= __put_user(0xb9cc0008, frame->tramp + 1);
406 /* Return from sighandler will jump to the tramp.
407 Negative 8 offset because return is rtsd r15, 8 */
408 regs->r15 = ((unsigned long)frame->tramp)-8;
410 __invalidate_cache_sigtramp((unsigned long)frame->tramp);
416 /* Set up registers for signal handler */
417 regs->r1 = (unsigned long) frame;
418 /* Signal handler args: */
419 regs->r5 = signal; /* arg 0: signum */
420 regs->r6 = (unsigned long) &frame->info; /* arg 1: siginfo */
421 regs->r7 = (unsigned long) &frame->uc; /* arg2: ucontext */
422 /* Offset to handle microblaze rtid r14, 0 */
423 regs->pc = (unsigned long)ka->sa.sa_handler;
428 printk(KERN_INFO "SIG deliver (%s:%d): sp=%p pc=%08lx\n",
429 current->comm, current->pid, frame, regs->pc);
436 ka->sa.sa_handler = SIG_DFL;
437 force_sig(SIGSEGV, current);
440 /* Handle restarting system calls */
442 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
445 case -ERESTART_RESTARTBLOCK:
446 case -ERESTARTNOHAND:
452 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
457 case -ERESTARTNOINTR:
459 /* offset of 4 bytes to re-execute trap (brki) instruction */
466 * OK, we're invoking a handler
470 handle_signal(unsigned long sig, struct k_sigaction *ka,
471 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
473 /* Set up the stack frame */
474 if (ka->sa.sa_flags & SA_SIGINFO)
475 setup_rt_frame(sig, ka, info, oldset, regs);
477 setup_frame(sig, ka, oldset, regs);
479 if (ka->sa.sa_flags & SA_ONESHOT)
480 ka->sa.sa_handler = SIG_DFL;
482 if (!(ka->sa.sa_flags & SA_NODEFER)) {
483 spin_lock_irq(¤t->sighand->siglock);
484 sigorsets(¤t->blocked,
485 ¤t->blocked, &ka->sa.sa_mask);
486 sigaddset(¤t->blocked, sig);
488 spin_unlock_irq(¤t->sighand->siglock);
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 * Note that we go through the signals twice: once to check the signals that
498 * the kernel can handle, and then we build all the user-level signal handling
499 * stack-frames in one go after that.
501 int do_signal(struct pt_regs *regs, sigset_t *oldset, int in_syscall)
505 struct k_sigaction ka;
507 printk(KERN_INFO "do signal: %p %p %d\n", regs, oldset, in_syscall);
508 printk(KERN_INFO "do signal2: %lx %lx %ld [%lx]\n", regs->pc, regs->r1,
509 regs->r12, current_thread_info()->flags);
512 * We want the common case to go fast, which
513 * is why we may in certain cases get here from
514 * kernel mode. Just return without doing anything
517 if (kernel_mode(regs))
521 oldset = ¤t->blocked;
523 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
525 /* Whee! Actually deliver the signal. */
527 handle_restart(regs, &ka, 1);
528 handle_signal(signr, &ka, &info, oldset, regs);
533 handle_restart(regs, NULL, 0);
535 /* Did we come from a system call? */