2 * linux/arch/arm26/kernel/signal.c
4 * Copyright (C) 1995-2002 Russell King
5 * Copyright (C) 2003 Ian Molton (ARM26)
7 * FIXME!!! This is probably very broken (13/05/2003)
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 #include <linux/sched.h>
15 #include <linux/smp.h>
16 #include <linux/kernel.h>
17 #include <linux/errno.h>
18 #include <linux/signal.h>
19 #include <linux/wait.h>
20 #include <linux/ptrace.h>
21 #include <linux/personality.h>
22 #include <linux/tty.h>
23 #include <linux/binfmts.h>
24 #include <linux/elf.h>
26 #include <asm/pgalloc.h>
27 #include <asm/ucontext.h>
28 #include <asm/uaccess.h>
29 #include <asm/unistd.h>
33 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
36 * For ARM syscalls, we encode the syscall number into the instruction.
38 #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn))
39 #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn))
41 static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall);
44 * atomically swap in the new signal mask, and wait for a signal.
46 asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask, struct pt_regs *regs)
51 spin_lock_irq(¤t->sighand->siglock);
52 saveset = current->blocked;
53 siginitset(¤t->blocked, mask);
55 spin_unlock_irq(¤t->sighand->siglock);
56 regs->ARM_r0 = -EINTR;
59 current->state = TASK_INTERRUPTIBLE;
61 if (do_signal(&saveset, regs, 0))
67 sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, struct pt_regs *regs)
69 sigset_t saveset, newset;
71 /* XXX: Don't preclude handling different sized sigset_t's. */
72 if (sigsetsize != sizeof(sigset_t))
75 if (copy_from_user(&newset, unewset, sizeof(newset)))
77 sigdelsetmask(&newset, ~_BLOCKABLE);
79 spin_lock_irq(¤t->sighand->siglock);
80 saveset = current->blocked;
81 current->blocked = newset;
83 spin_unlock_irq(¤t->sighand->siglock);
84 regs->ARM_r0 = -EINTR;
87 current->state = TASK_INTERRUPTIBLE;
89 if (do_signal(&saveset, regs, 0))
95 sys_sigaction(int sig, const struct old_sigaction *act,
96 struct old_sigaction *oact)
98 struct k_sigaction new_ka, old_ka;
103 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
104 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
105 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
107 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
108 __get_user(mask, &act->sa_mask);
109 siginitset(&new_ka.sa.sa_mask, mask);
112 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
115 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
116 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
117 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
119 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
120 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
127 * Do a signal return; undo the signal stack.
131 struct sigcontext sc;
132 unsigned long extramask[_NSIG_WORDS-1];
133 unsigned long retcode;
138 struct siginfo *pinfo;
142 unsigned long retcode;
146 restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc)
150 __get_user_error(regs->ARM_r0, &sc->arm_r0, err);
151 __get_user_error(regs->ARM_r1, &sc->arm_r1, err);
152 __get_user_error(regs->ARM_r2, &sc->arm_r2, err);
153 __get_user_error(regs->ARM_r3, &sc->arm_r3, err);
154 __get_user_error(regs->ARM_r4, &sc->arm_r4, err);
155 __get_user_error(regs->ARM_r5, &sc->arm_r5, err);
156 __get_user_error(regs->ARM_r6, &sc->arm_r6, err);
157 __get_user_error(regs->ARM_r7, &sc->arm_r7, err);
158 __get_user_error(regs->ARM_r8, &sc->arm_r8, err);
159 __get_user_error(regs->ARM_r9, &sc->arm_r9, err);
160 __get_user_error(regs->ARM_r10, &sc->arm_r10, err);
161 __get_user_error(regs->ARM_fp, &sc->arm_fp, err);
162 __get_user_error(regs->ARM_ip, &sc->arm_ip, err);
163 __get_user_error(regs->ARM_sp, &sc->arm_sp, err);
164 __get_user_error(regs->ARM_lr, &sc->arm_lr, err);
165 __get_user_error(regs->ARM_pc, &sc->arm_pc, err);
167 err |= !valid_user_regs(regs);
172 asmlinkage int sys_sigreturn(struct pt_regs *regs)
174 struct sigframe *frame;
178 * Since we stacked the signal on a 64-bit boundary,
179 * then 'sp' should be word aligned here. If it's
180 * not, then the user is trying to mess with us.
182 if (regs->ARM_sp & 7)
185 frame = (struct sigframe *)regs->ARM_sp;
187 if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
189 if (__get_user(set.sig[0], &frame->sc.oldmask)
191 && __copy_from_user(&set.sig[1], &frame->extramask,
192 sizeof(frame->extramask))))
195 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))
204 /* Send SIGTRAP if we're single-stepping */
205 if (current->ptrace & PT_SINGLESTEP) {
206 ptrace_cancel_bpt(current);
207 send_sig(SIGTRAP, current, 1);
213 force_sig(SIGSEGV, current);
217 asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
219 struct rt_sigframe *frame;
223 * Since we stacked the signal on a 64-bit boundary,
224 * then 'sp' should be word aligned here. If it's
225 * not, then the user is trying to mess with us.
227 if (regs->ARM_sp & 7)
230 frame = (struct rt_sigframe *)regs->ARM_sp;
232 if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
234 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
237 sigdelsetmask(&set, ~_BLOCKABLE);
238 spin_lock_irq(¤t->sighand->siglock);
239 current->blocked = set;
241 spin_unlock_irq(¤t->sighand->siglock);
243 if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
246 /* Send SIGTRAP if we're single-stepping */
247 if (current->ptrace & PT_SINGLESTEP) {
248 ptrace_cancel_bpt(current);
249 send_sig(SIGTRAP, current, 1);
255 force_sig(SIGSEGV, current);
260 setup_sigcontext(struct sigcontext *sc, /*struct _fpstate *fpstate,*/
261 struct pt_regs *regs, unsigned long mask)
265 __put_user_error(regs->ARM_r0, &sc->arm_r0, err);
266 __put_user_error(regs->ARM_r1, &sc->arm_r1, err);
267 __put_user_error(regs->ARM_r2, &sc->arm_r2, err);
268 __put_user_error(regs->ARM_r3, &sc->arm_r3, err);
269 __put_user_error(regs->ARM_r4, &sc->arm_r4, err);
270 __put_user_error(regs->ARM_r5, &sc->arm_r5, err);
271 __put_user_error(regs->ARM_r6, &sc->arm_r6, err);
272 __put_user_error(regs->ARM_r7, &sc->arm_r7, err);
273 __put_user_error(regs->ARM_r8, &sc->arm_r8, err);
274 __put_user_error(regs->ARM_r9, &sc->arm_r9, err);
275 __put_user_error(regs->ARM_r10, &sc->arm_r10, err);
276 __put_user_error(regs->ARM_fp, &sc->arm_fp, err);
277 __put_user_error(regs->ARM_ip, &sc->arm_ip, err);
278 __put_user_error(regs->ARM_sp, &sc->arm_sp, err);
279 __put_user_error(regs->ARM_lr, &sc->arm_lr, err);
280 __put_user_error(regs->ARM_pc, &sc->arm_pc, err);
282 __put_user_error(current->thread.trap_no, &sc->trap_no, err);
283 __put_user_error(current->thread.error_code, &sc->error_code, err);
284 __put_user_error(current->thread.address, &sc->fault_address, err);
285 __put_user_error(mask, &sc->oldmask, err);
291 get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, int framesize)
293 unsigned long sp = regs->ARM_sp;
296 * This is the X/Open sanctioned signal stack switching.
298 if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp))
299 sp = current->sas_ss_sp + current->sas_ss_size;
302 * ATPCS B01 mandates 8-byte alignment
304 return (void *)((sp - framesize) & ~7);
308 setup_return(struct pt_regs *regs, struct k_sigaction *ka,
309 unsigned long *rc, void *frame, int usig)
311 unsigned long handler = (unsigned long)ka->sa.sa_handler;
312 unsigned long retcode;
314 if (ka->sa.sa_flags & SA_RESTORER) {
315 retcode = (unsigned long)ka->sa.sa_restorer;
318 if (__put_user((ka->sa.sa_flags & SA_SIGINFO)?SWI_SYS_RT_SIGRETURN:SWI_SYS_SIGRETURN, rc))
321 retcode = ((unsigned long)rc);
325 regs->ARM_sp = (unsigned long)frame;
326 regs->ARM_lr = retcode;
327 regs->ARM_pc = handler & ~3;
333 setup_frame(int usig, struct k_sigaction *ka, sigset_t *set, struct pt_regs *regs)
335 struct sigframe *frame = get_sigframe(ka, regs, sizeof(*frame));
338 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
341 err |= setup_sigcontext(&frame->sc, /*&frame->fpstate,*/ regs, set->sig[0]);
343 if (_NSIG_WORDS > 1) {
344 err |= __copy_to_user(frame->extramask, &set->sig[1],
345 sizeof(frame->extramask));
349 err = setup_return(regs, ka, &frame->retcode, frame, usig);
355 setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
356 sigset_t *set, struct pt_regs *regs)
358 struct rt_sigframe *frame = get_sigframe(ka, regs, sizeof(*frame));
361 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
364 __put_user_error(&frame->info, &frame->pinfo, err);
365 __put_user_error(&frame->uc, &frame->puc, err);
366 err |= copy_siginfo_to_user(&frame->info, info);
368 /* Clear all the bits of the ucontext we don't use. */
369 err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));
371 err |= setup_sigcontext(&frame->uc.uc_mcontext, /*&frame->fpstate,*/
373 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
376 err = setup_return(regs, ka, &frame->retcode, frame, usig);
380 * For realtime signals we must also set the second and third
381 * arguments for the signal handler.
382 * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06
384 regs->ARM_r1 = (unsigned long)frame->pinfo;
385 regs->ARM_r2 = (unsigned long)frame->puc;
391 static inline void restart_syscall(struct pt_regs *regs)
393 regs->ARM_r0 = regs->ARM_ORIG_r0;
398 * OK, we're invoking a handler
401 handle_signal(unsigned long sig, siginfo_t *info, sigset_t *oldset,
402 struct pt_regs * regs, int syscall)
404 struct thread_info *thread = current_thread_info();
405 struct task_struct *tsk = current;
406 struct k_sigaction *ka = &tsk->sighand->action[sig-1];
411 * If we were from a system call, check for system call restarting...
414 switch (regs->ARM_r0) {
415 case -ERESTART_RESTARTBLOCK:
416 current_thread_info()->restart_block.fn =
417 do_no_restart_syscall;
418 case -ERESTARTNOHAND:
419 regs->ARM_r0 = -EINTR;
422 if (!(ka->sa.sa_flags & SA_RESTART)) {
423 regs->ARM_r0 = -EINTR;
427 case -ERESTARTNOINTR:
428 restart_syscall(regs);
433 * translate the signal
435 if (usig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap)
436 usig = thread->exec_domain->signal_invmap[usig];
439 * Set up the stack frame
441 if (ka->sa.sa_flags & SA_SIGINFO)
442 ret = setup_rt_frame(usig, ka, info, oldset, regs);
444 ret = setup_frame(usig, ka, oldset, regs);
447 * Check that the resulting registers are actually sane.
449 ret |= !valid_user_regs(regs);
452 if (ka->sa.sa_flags & SA_ONESHOT)
453 ka->sa.sa_handler = SIG_DFL;
455 spin_lock_irq(&tsk->sighand->siglock);
456 sigorsets(&tsk->blocked, &tsk->blocked,
458 if (!(ka->sa.sa_flags & SA_NODEFER))
459 sigaddset(&tsk->blocked, sig);
461 spin_unlock_irq(&tsk->sighand->siglock);
465 force_sigsegv(sig, tsk);
469 * Note that 'init' is a special process: it doesn't get signals it doesn't
470 * want to handle. Thus you cannot kill init even with a SIGKILL even by
473 * Note that we go through the signals twice: once to check the signals that
474 * the kernel can handle, and then we build all the user-level signal handling
475 * stack-frames in one go after that.
477 static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall)
481 struct k_sigaction ka;
484 * We want the common case to go fast, which
485 * is why we may in certain cases get here from
486 * kernel mode. Just return without doing anything
489 if (!user_mode(regs))
492 if (current->ptrace & PT_SINGLESTEP)
493 ptrace_cancel_bpt(current);
495 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
497 handle_signal(signr, &info, oldset, regs, syscall);
498 if (current->ptrace & PT_SINGLESTEP)
499 ptrace_set_bpt(current);
504 * No signal to deliver to the process - restart the syscall.
507 if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) {
511 usp = (u32 *)regs->ARM_sp;
513 put_user(regs->ARM_pc, &usp[0]);
514 /* swi __NR_restart_syscall */
515 put_user(0xef000000 | __NR_restart_syscall, &usp[1]);
516 /* ldr pc, [sp], #12 */
517 // FIXME!!! is #12 correct there?
518 put_user(0xe49df00c, &usp[2]);
520 regs->ARM_pc = regs->ARM_sp + 4;
522 if (regs->ARM_r0 == -ERESTARTNOHAND ||
523 regs->ARM_r0 == -ERESTARTSYS ||
524 regs->ARM_r0 == -ERESTARTNOINTR) {
525 restart_syscall(regs);
528 if (current->ptrace & PT_SINGLESTEP)
529 ptrace_set_bpt(current);
534 do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall)
536 if (thread_flags & _TIF_SIGPENDING)
537 do_signal(¤t->blocked, regs, syscall);