1 /* MN10300 Signal handling
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
12 #include <linux/sched.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/stddef.h>
22 #include <linux/tty.h>
23 #include <linux/personality.h>
24 #include <linux/suspend.h>
25 #include <linux/tracehook.h>
26 #include <asm/cacheflush.h>
27 #include <asm/ucontext.h>
28 #include <asm/uaccess.h>
35 * atomically swap in the new signal mask, and wait for a signal.
37 asmlinkage long sys_sigsuspend(int history0, int history1, old_sigset_t mask)
40 siginitset(&blocked, mask);
41 return sigsuspend(&blocked);
45 * set signal action syscall
47 asmlinkage long sys_sigaction(int sig,
48 const struct old_sigaction __user *act,
49 struct old_sigaction __user *oact)
51 struct k_sigaction new_ka, old_ka;
56 if (verify_area(VERIFY_READ, act, sizeof(*act)) ||
57 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
58 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
59 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
60 __get_user(mask, &act->sa_mask))
62 siginitset(&new_ka.sa.sa_mask, mask);
65 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
68 if (verify_area(VERIFY_WRITE, oact, sizeof(*oact)) ||
69 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
70 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
71 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
72 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
80 * set alternate signal stack syscall
82 asmlinkage long sys_sigaltstack(const stack_t __user *uss, stack_t *uoss)
84 return do_sigaltstack(uss, uoss, current_frame()->sp);
88 * do a signal return; undo the signal stack.
90 static int restore_sigcontext(struct pt_regs *regs,
91 struct sigcontext __user *sc, long *_d0)
95 /* Always make any pending restarted system calls return -EINTR */
96 current_thread_info()->restart_block.fn = do_no_restart_syscall;
98 if (is_using_fpu(current))
99 fpu_kill_state(current);
101 #define COPY(x) err |= __get_user(regs->x, &sc->x)
102 COPY(d1); COPY(d2); COPY(d3);
103 COPY(a0); COPY(a1); COPY(a2); COPY(a3);
104 COPY(e0); COPY(e1); COPY(e2); COPY(e3);
105 COPY(e4); COPY(e5); COPY(e6); COPY(e7);
106 COPY(lar); COPY(lir);
107 COPY(mdr); COPY(mdrq);
108 COPY(mcvf); COPY(mcrl); COPY(mcrh);
113 unsigned int tmpflags;
114 #ifndef CONFIG_MN10300_USING_JTAG
115 #define USER_EPSW (EPSW_FLAG_Z | EPSW_FLAG_N | EPSW_FLAG_C | EPSW_FLAG_V | \
118 #define USER_EPSW (EPSW_FLAG_Z | EPSW_FLAG_N | EPSW_FLAG_C | EPSW_FLAG_V | \
121 err |= __get_user(tmpflags, &sc->epsw);
122 regs->epsw = (regs->epsw & ~USER_EPSW) |
123 (tmpflags & USER_EPSW);
124 regs->orig_d0 = -1; /* disable syscall checks */
128 struct fpucontext *buf;
129 err |= __get_user(buf, &sc->fpucontext);
131 if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
133 err |= fpu_restore_sigcontext(buf);
137 err |= __get_user(*_d0, &sc->d0);
145 * standard signal return syscall
147 asmlinkage long sys_sigreturn(void)
149 struct sigframe __user *frame;
153 frame = (struct sigframe __user *) current_frame()->sp;
154 if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
156 if (__get_user(set.sig[0], &frame->sc.oldmask))
159 if (_NSIG_WORDS > 1 &&
160 __copy_from_user(&set.sig[1], &frame->extramask,
161 sizeof(frame->extramask)))
164 set_current_blocked(&set);
166 if (restore_sigcontext(current_frame(), &frame->sc, &d0))
172 force_sig(SIGSEGV, current);
177 * realtime signal return syscall
179 asmlinkage long sys_rt_sigreturn(void)
181 struct rt_sigframe __user *frame;
185 frame = (struct rt_sigframe __user *) current_frame()->sp;
186 if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
188 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
191 set_current_blocked(&set);
193 if (restore_sigcontext(current_frame(), &frame->uc.uc_mcontext, &d0))
196 if (do_sigaltstack(&frame->uc.uc_stack, NULL, current_frame()->sp) ==
203 force_sig(SIGSEGV, current);
208 * store the userspace context into a signal frame
210 static int setup_sigcontext(struct sigcontext __user *sc,
211 struct fpucontext *fpuctx,
212 struct pt_regs *regs,
217 #define COPY(x) err |= __put_user(regs->x, &sc->x)
218 COPY(d0); COPY(d1); COPY(d2); COPY(d3);
219 COPY(a0); COPY(a1); COPY(a2); COPY(a3);
220 COPY(e0); COPY(e1); COPY(e2); COPY(e3);
221 COPY(e4); COPY(e5); COPY(e6); COPY(e7);
222 COPY(lar); COPY(lir);
223 COPY(mdr); COPY(mdrq);
224 COPY(mcvf); COPY(mcrl); COPY(mcrh);
225 COPY(sp); COPY(epsw); COPY(pc);
228 tmp = fpu_setup_sigcontext(fpuctx);
232 err |= __put_user(tmp ? fpuctx : NULL, &sc->fpucontext);
234 /* non-iBCS2 extensions.. */
235 err |= __put_user(mask, &sc->oldmask);
241 * determine which stack to use..
243 static inline void __user *get_sigframe(struct k_sigaction *ka,
244 struct pt_regs *regs,
249 /* default to using normal stack */
252 /* this is the X/Open sanctioned signal stack switching. */
253 if (ka->sa.sa_flags & SA_ONSTACK) {
254 if (sas_ss_flags(sp) == 0)
255 sp = current->sas_ss_sp + current->sas_ss_size;
258 return (void __user *) ((sp - frame_size) & ~7UL);
262 * set up a normal signal frame
264 static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
265 struct pt_regs *regs)
267 struct sigframe __user *frame;
270 frame = get_sigframe(ka, regs, sizeof(*frame));
272 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
277 current_thread_info()->exec_domain &&
278 current_thread_info()->exec_domain->signal_invmap)
279 rsig = current_thread_info()->exec_domain->signal_invmap[sig];
281 if (__put_user(rsig, &frame->sig) < 0 ||
282 __put_user(&frame->sc, &frame->psc) < 0)
285 if (setup_sigcontext(&frame->sc, &frame->fpuctx, regs, set->sig[0]))
288 if (_NSIG_WORDS > 1) {
289 if (__copy_to_user(frame->extramask, &set->sig[1],
290 sizeof(frame->extramask)))
294 /* set up to return from userspace. If provided, use a stub already in
296 if (ka->sa.sa_flags & SA_RESTORER) {
297 if (__put_user(ka->sa.sa_restorer, &frame->pretcode))
300 if (__put_user((void (*)(void))frame->retcode,
303 /* this is mov $,d0; syscall 0 */
304 if (__put_user(0x2c, (char *)(frame->retcode + 0)) ||
305 __put_user(__NR_sigreturn, (char *)(frame->retcode + 1)) ||
306 __put_user(0x00, (char *)(frame->retcode + 2)) ||
307 __put_user(0xf0, (char *)(frame->retcode + 3)) ||
308 __put_user(0xe0, (char *)(frame->retcode + 4)))
310 flush_icache_range((unsigned long) frame->retcode,
311 (unsigned long) frame->retcode + 5);
314 /* set up registers for signal handler */
315 regs->sp = (unsigned long) frame;
316 regs->pc = (unsigned long) ka->sa.sa_handler;
318 regs->d1 = (unsigned long) &frame->sc;
320 /* the tracer may want to single-step inside the handler */
321 if (test_thread_flag(TIF_SINGLESTEP))
322 ptrace_notify(SIGTRAP);
325 printk(KERN_DEBUG "SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
326 sig, current->comm, current->pid, frame, regs->pc,
333 force_sigsegv(sig, current);
338 * set up a realtime signal frame
340 static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
341 sigset_t *set, struct pt_regs *regs)
343 struct rt_sigframe __user *frame;
346 frame = get_sigframe(ka, regs, sizeof(*frame));
348 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
353 current_thread_info()->exec_domain &&
354 current_thread_info()->exec_domain->signal_invmap)
355 rsig = current_thread_info()->exec_domain->signal_invmap[sig];
357 if (__put_user(rsig, &frame->sig) ||
358 __put_user(&frame->info, &frame->pinfo) ||
359 __put_user(&frame->uc, &frame->puc) ||
360 copy_siginfo_to_user(&frame->info, info))
363 /* create the ucontext. */
364 if (__put_user(0, &frame->uc.uc_flags) ||
365 __put_user(0, &frame->uc.uc_link) ||
366 __put_user((void *)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp) ||
367 __put_user(sas_ss_flags(regs->sp), &frame->uc.uc_stack.ss_flags) ||
368 __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size) ||
369 setup_sigcontext(&frame->uc.uc_mcontext,
370 &frame->fpuctx, regs, set->sig[0]) ||
371 __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
374 /* set up to return from userspace. If provided, use a stub already in
376 if (ka->sa.sa_flags & SA_RESTORER) {
377 if (__put_user(ka->sa.sa_restorer, &frame->pretcode))
380 if (__put_user((void(*)(void))frame->retcode,
382 /* This is mov $,d0; syscall 0 */
383 __put_user(0x2c, (char *)(frame->retcode + 0)) ||
384 __put_user(__NR_rt_sigreturn,
385 (char *)(frame->retcode + 1)) ||
386 __put_user(0x00, (char *)(frame->retcode + 2)) ||
387 __put_user(0xf0, (char *)(frame->retcode + 3)) ||
388 __put_user(0xe0, (char *)(frame->retcode + 4)))
391 flush_icache_range((u_long) frame->retcode,
392 (u_long) frame->retcode + 5);
395 /* Set up registers for signal handler */
396 regs->sp = (unsigned long) frame;
397 regs->pc = (unsigned long) ka->sa.sa_handler;
399 regs->d1 = (long) &frame->info;
401 /* the tracer may want to single-step inside the handler */
402 if (test_thread_flag(TIF_SINGLESTEP))
403 ptrace_notify(SIGTRAP);
406 printk(KERN_DEBUG "SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
407 sig, current->comm, current->pid, frame, regs->pc,
414 force_sigsegv(sig, current);
418 static inline void stepback(struct pt_regs *regs)
425 * handle the actual delivery of a signal to userspace
427 static int handle_signal(int sig,
428 siginfo_t *info, struct k_sigaction *ka,
429 struct pt_regs *regs)
431 sigset_t *oldset = sigmask_to_save();
434 /* Are we from a system call? */
435 if (regs->orig_d0 >= 0) {
436 /* If so, check system call restarting.. */
438 case -ERESTART_RESTARTBLOCK:
439 case -ERESTARTNOHAND:
444 if (!(ka->sa.sa_flags & SA_RESTART)) {
450 case -ERESTARTNOINTR:
451 regs->d0 = regs->orig_d0;
456 /* Set up the stack frame */
457 if (ka->sa.sa_flags & SA_SIGINFO)
458 ret = setup_rt_frame(sig, ka, info, oldset, regs);
460 ret = setup_frame(sig, ka, oldset, regs);
464 signal_delivered(sig, info, ka, regs,
465 test_thread_flag(TIF_SINGLESTEP));
469 * handle a potential signal
471 static void do_signal(struct pt_regs *regs)
473 struct k_sigaction ka;
477 /* we want the common case to go fast, which is why we may in certain
478 * cases get here from kernel mode */
479 if (!user_mode(regs))
482 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
484 if (handle_signal(signr, &info, &ka, regs) == 0) {
490 /* did we come from a system call? */
491 if (regs->orig_d0 >= 0) {
492 /* restart the system call - no handlers present */
494 case -ERESTARTNOHAND:
496 case -ERESTARTNOINTR:
497 regs->d0 = regs->orig_d0;
501 case -ERESTART_RESTARTBLOCK:
502 regs->d0 = __NR_restart_syscall;
508 /* if there's no signal to deliver, we just put the saved sigmask
510 restore_saved_sigmask();
514 * notification of userspace execution resumption
515 * - triggered by current->work.notify_resume
517 asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)
519 /* Pending single-step? */
520 if (thread_info_flags & _TIF_SINGLESTEP) {
521 #ifndef CONFIG_MN10300_USING_JTAG
522 regs->epsw |= EPSW_T;
523 clear_thread_flag(TIF_SINGLESTEP);
525 BUG(); /* no h/w single-step if using JTAG unit */
529 /* deal with pending signal delivery */
530 if (thread_info_flags & _TIF_SIGPENDING)
533 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
534 clear_thread_flag(TIF_NOTIFY_RESUME);
535 tracehook_notify_resume(current_frame());