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 <asm/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;
181 frame = get_sigframe(ksig, sizeof(*frame));
183 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
186 if (__put_user(sig, &frame->sig) < 0)
189 if (setup_sigcontext(&frame->sc, set->sig[0]))
192 if (_NSIG_WORDS > 1) {
193 if (__copy_to_user(frame->extramask, &set->sig[1],
194 sizeof(frame->extramask)))
198 /* Set up to return from userspace. If provided, use a stub
199 * already in userspace. */
200 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
201 if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode) < 0)
205 /* Set up the following code on the stack:
206 * setlos #__NR_sigreturn,gr7
209 if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
210 __put_user(0x8efc0000|__NR_sigreturn, &frame->retcode[0]) ||
211 __put_user(0xc0700000, &frame->retcode[1]))
214 flush_icache_range((unsigned long) frame->retcode,
215 (unsigned long) (frame->retcode + 2));
218 /* Set up registers for the signal handler */
219 if (current->personality & FDPIC_FUNCPTRS) {
220 struct fdpic_func_descriptor __user *funcptr =
221 (struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
222 struct fdpic_func_descriptor desc;
223 if (copy_from_user(&desc, funcptr, sizeof(desc)))
225 __frame->pc = desc.text;
226 __frame->gr15 = desc.GOT;
228 __frame->pc = (unsigned long) ksig->ka.sa.sa_handler;
232 __frame->sp = (unsigned long) frame;
233 __frame->lr = (unsigned long) &frame->retcode;
237 printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
238 sig, current->comm, current->pid, frame, __frame->pc,
243 } /* end setup_frame() */
245 /*****************************************************************************/
249 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set)
251 struct rt_sigframe __user *frame;
256 frame = get_sigframe(ksig, sizeof(*frame));
258 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
261 if (__put_user(sig, &frame->sig) ||
262 __put_user(&frame->info, &frame->pinfo) ||
263 __put_user(&frame->uc, &frame->puc))
266 if (copy_siginfo_to_user(&frame->info, &ksig->info))
269 /* Create the ucontext. */
270 if (__put_user(0, &frame->uc.uc_flags) ||
271 __put_user(NULL, &frame->uc.uc_link) ||
272 __save_altstack(&frame->uc.uc_stack, __frame->sp))
275 if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
278 if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
281 /* Set up to return from userspace. If provided, use a stub
282 * already in userspace. */
283 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
284 if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
288 /* Set up the following code on the stack:
289 * setlos #__NR_sigreturn,gr7
292 if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
293 __put_user(0x8efc0000|__NR_rt_sigreturn, &frame->retcode[0]) ||
294 __put_user(0xc0700000, &frame->retcode[1]))
297 flush_icache_range((unsigned long) frame->retcode,
298 (unsigned long) (frame->retcode + 2));
301 /* Set up registers for signal handler */
302 if (current->personality & FDPIC_FUNCPTRS) {
303 struct fdpic_func_descriptor __user *funcptr =
304 (struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
305 struct fdpic_func_descriptor desc;
306 if (copy_from_user(&desc, funcptr, sizeof(desc)))
308 __frame->pc = desc.text;
309 __frame->gr15 = desc.GOT;
311 __frame->pc = (unsigned long) ksig->ka.sa.sa_handler;
315 __frame->sp = (unsigned long) frame;
316 __frame->lr = (unsigned long) &frame->retcode;
318 __frame->gr9 = (unsigned long) &frame->info;
321 printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
322 sig, current->comm, current->pid, frame, __frame->pc,
327 } /* end setup_rt_frame() */
329 /*****************************************************************************/
331 * OK, we're invoking a handler
333 static void handle_signal(struct ksignal *ksig)
335 sigset_t *oldset = sigmask_to_save();
338 /* Are we from a system call? */
339 if (__frame->syscallno != -1) {
340 /* If so, check system call restarting.. */
341 switch (__frame->gr8) {
342 case -ERESTART_RESTARTBLOCK:
343 case -ERESTARTNOHAND:
344 __frame->gr8 = -EINTR;
348 if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
349 __frame->gr8 = -EINTR;
354 case -ERESTARTNOINTR:
355 __frame->gr8 = __frame->orig_gr8;
358 __frame->syscallno = -1;
361 /* Set up the stack frame */
362 if (ksig->ka.sa.sa_flags & SA_SIGINFO)
363 ret = setup_rt_frame(ksig, oldset);
365 ret = setup_frame(ksig, oldset);
367 signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
368 } /* end handle_signal() */
370 /*****************************************************************************/
372 * Note that 'init' is a special process: it doesn't get signals it doesn't
373 * want to handle. Thus you cannot kill init even with a SIGKILL even by
376 static void do_signal(void)
380 if (get_signal(&ksig)) {
381 handle_signal(&ksig);
385 /* Did we come from a system call? */
386 if (__frame->syscallno != -1) {
387 /* Restart the system call - no handlers present */
388 switch (__frame->gr8) {
389 case -ERESTARTNOHAND:
391 case -ERESTARTNOINTR:
392 __frame->gr8 = __frame->orig_gr8;
396 case -ERESTART_RESTARTBLOCK:
397 __frame->gr7 = __NR_restart_syscall;
401 __frame->syscallno = -1;
404 /* if there's no signal to deliver, we just put the saved sigmask
406 restore_saved_sigmask();
407 } /* end do_signal() */
409 /*****************************************************************************/
411 * notification of userspace execution resumption
412 * - triggered by the TIF_WORK_MASK flags
414 asmlinkage void do_notify_resume(__u32 thread_info_flags)
416 /* pending single-step? */
417 if (thread_info_flags & _TIF_SINGLESTEP)
418 clear_thread_flag(TIF_SINGLESTEP);
420 /* deal with pending signal delivery */
421 if (thread_info_flags & _TIF_SIGPENDING)
424 /* deal with notification on about to resume userspace execution */
425 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
426 clear_thread_flag(TIF_NOTIFY_RESUME);
427 tracehook_notify_resume(__frame);
430 } /* end do_notify_resume() */