1 /* signal.c: FRV specific bits of signal handling
3 * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 * - Derived from arch/m68k/kernel/signal.c
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
13 #include <linux/sched.h>
15 #include <linux/smp.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/personality.h>
23 #include <linux/tracehook.h>
24 #include <asm/ucontext.h>
25 #include <linux/uaccess.h>
26 #include <asm/cacheflush.h>
30 struct fdpic_func_descriptor {
36 * Do a signal return; undo the signal stack.
41 __sigrestore_t pretcode;
44 unsigned long extramask[_NSIG_WORDS-1];
50 __sigrestore_t pretcode;
52 struct siginfo __user *pinfo;
59 static int restore_sigcontext(struct sigcontext __user *sc, int *_gr8)
61 struct user_context *user = current->thread.user;
62 unsigned long tbr, psr;
64 /* Always make any pending restarted system calls return -EINTR */
65 current->restart_block.fn = do_no_restart_syscall;
69 if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))
74 restore_user_regs(user);
76 user->i.syscallno = -1; /* disable syscall checks */
78 *_gr8 = user->i.gr[8];
85 asmlinkage int sys_sigreturn(void)
87 struct sigframe __user *frame = (struct sigframe __user *) __frame->sp;
91 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
93 if (__get_user(set.sig[0], &frame->sc.sc_oldmask))
96 if (_NSIG_WORDS > 1 &&
97 __copy_from_user(&set.sig[1], &frame->extramask, sizeof(frame->extramask)))
100 set_current_blocked(&set);
102 if (restore_sigcontext(&frame->sc, &gr8))
107 force_sig(SIGSEGV, current);
111 asmlinkage int sys_rt_sigreturn(void)
113 struct rt_sigframe __user *frame = (struct rt_sigframe __user *) __frame->sp;
117 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
119 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
122 set_current_blocked(&set);
124 if (restore_sigcontext(&frame->uc.uc_mcontext, &gr8))
127 if (restore_altstack(&frame->uc.uc_stack))
133 force_sig(SIGSEGV, current);
138 * Set up a signal frame
140 static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
142 save_user_regs(current->thread.user);
144 if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
147 /* non-iBCS2 extensions.. */
148 if (__put_user(mask, &sc->sc_oldmask) < 0)
157 /*****************************************************************************/
159 * Determine which stack to use..
161 static inline void __user *get_sigframe(struct ksignal *ksig,
164 unsigned long sp = sigsp(__frame->sp, ksig);
166 return (void __user *) ((sp - frame_size) & ~7UL);
168 } /* end get_sigframe() */
170 /*****************************************************************************/
174 static int setup_frame(struct ksignal *ksig, sigset_t *set)
176 struct sigframe __user *frame;
179 frame = get_sigframe(ksig, sizeof(*frame));
181 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
184 if (__put_user(sig, &frame->sig) < 0)
187 if (setup_sigcontext(&frame->sc, set->sig[0]))
190 if (_NSIG_WORDS > 1) {
191 if (__copy_to_user(frame->extramask, &set->sig[1],
192 sizeof(frame->extramask)))
196 /* Set up to return from userspace. If provided, use a stub
197 * already in userspace. */
198 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
199 if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode) < 0)
203 /* Set up the following code on the stack:
204 * setlos #__NR_sigreturn,gr7
207 if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
208 __put_user(0x8efc0000|__NR_sigreturn, &frame->retcode[0]) ||
209 __put_user(0xc0700000, &frame->retcode[1]))
212 flush_icache_range((unsigned long) frame->retcode,
213 (unsigned long) (frame->retcode + 2));
216 /* Set up registers for the signal handler */
217 if (current->personality & FDPIC_FUNCPTRS) {
218 struct fdpic_func_descriptor __user *funcptr =
219 (struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
220 struct fdpic_func_descriptor desc;
221 if (copy_from_user(&desc, funcptr, sizeof(desc)))
223 __frame->pc = desc.text;
224 __frame->gr15 = desc.GOT;
226 __frame->pc = (unsigned long) ksig->ka.sa.sa_handler;
230 __frame->sp = (unsigned long) frame;
231 __frame->lr = (unsigned long) &frame->retcode;
235 printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
236 sig, current->comm, current->pid, frame, __frame->pc,
241 } /* end setup_frame() */
243 /*****************************************************************************/
247 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set)
249 struct rt_sigframe __user *frame;
252 frame = get_sigframe(ksig, sizeof(*frame));
254 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
257 if (__put_user(sig, &frame->sig) ||
258 __put_user(&frame->info, &frame->pinfo) ||
259 __put_user(&frame->uc, &frame->puc))
262 if (copy_siginfo_to_user(&frame->info, &ksig->info))
265 /* Create the ucontext. */
266 if (__put_user(0, &frame->uc.uc_flags) ||
267 __put_user(NULL, &frame->uc.uc_link) ||
268 __save_altstack(&frame->uc.uc_stack, __frame->sp))
271 if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
274 if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
277 /* Set up to return from userspace. If provided, use a stub
278 * already in userspace. */
279 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
280 if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
284 /* Set up the following code on the stack:
285 * setlos #__NR_sigreturn,gr7
288 if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
289 __put_user(0x8efc0000|__NR_rt_sigreturn, &frame->retcode[0]) ||
290 __put_user(0xc0700000, &frame->retcode[1]))
293 flush_icache_range((unsigned long) frame->retcode,
294 (unsigned long) (frame->retcode + 2));
297 /* Set up registers for signal handler */
298 if (current->personality & FDPIC_FUNCPTRS) {
299 struct fdpic_func_descriptor __user *funcptr =
300 (struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
301 struct fdpic_func_descriptor desc;
302 if (copy_from_user(&desc, funcptr, sizeof(desc)))
304 __frame->pc = desc.text;
305 __frame->gr15 = desc.GOT;
307 __frame->pc = (unsigned long) ksig->ka.sa.sa_handler;
311 __frame->sp = (unsigned long) frame;
312 __frame->lr = (unsigned long) &frame->retcode;
314 __frame->gr9 = (unsigned long) &frame->info;
317 printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
318 sig, current->comm, current->pid, frame, __frame->pc,
323 } /* end setup_rt_frame() */
325 /*****************************************************************************/
327 * OK, we're invoking a handler
329 static void handle_signal(struct ksignal *ksig)
331 sigset_t *oldset = sigmask_to_save();
334 /* Are we from a system call? */
335 if (__frame->syscallno != -1) {
336 /* If so, check system call restarting.. */
337 switch (__frame->gr8) {
338 case -ERESTART_RESTARTBLOCK:
339 case -ERESTARTNOHAND:
340 __frame->gr8 = -EINTR;
344 if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
345 __frame->gr8 = -EINTR;
350 case -ERESTARTNOINTR:
351 __frame->gr8 = __frame->orig_gr8;
354 __frame->syscallno = -1;
357 /* Set up the stack frame */
358 if (ksig->ka.sa.sa_flags & SA_SIGINFO)
359 ret = setup_rt_frame(ksig, oldset);
361 ret = setup_frame(ksig, oldset);
363 signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
364 } /* end handle_signal() */
366 /*****************************************************************************/
368 * Note that 'init' is a special process: it doesn't get signals it doesn't
369 * want to handle. Thus you cannot kill init even with a SIGKILL even by
372 static void do_signal(void)
376 if (get_signal(&ksig)) {
377 handle_signal(&ksig);
381 /* Did we come from a system call? */
382 if (__frame->syscallno != -1) {
383 /* Restart the system call - no handlers present */
384 switch (__frame->gr8) {
385 case -ERESTARTNOHAND:
387 case -ERESTARTNOINTR:
388 __frame->gr8 = __frame->orig_gr8;
392 case -ERESTART_RESTARTBLOCK:
393 __frame->gr7 = __NR_restart_syscall;
397 __frame->syscallno = -1;
400 /* if there's no signal to deliver, we just put the saved sigmask
402 restore_saved_sigmask();
403 } /* end do_signal() */
405 /*****************************************************************************/
407 * notification of userspace execution resumption
408 * - triggered by the TIF_WORK_MASK flags
410 asmlinkage void do_notify_resume(__u32 thread_info_flags)
412 /* pending single-step? */
413 if (thread_info_flags & _TIF_SINGLESTEP)
414 clear_thread_flag(TIF_SINGLESTEP);
416 /* deal with pending signal delivery */
417 if (thread_info_flags & _TIF_SIGPENDING)
420 /* deal with notification on about to resume userspace execution */
421 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
422 clear_thread_flag(TIF_NOTIFY_RESUME);
423 tracehook_notify_resume(__frame);
426 } /* end do_notify_resume() */