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);
50 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
53 return do_sigaltstack(uss, uoss, regs->r1);
57 * Do a signal return; undo the signal stack.
61 unsigned long extramask[_NSIG_WORDS-1];
62 unsigned long tramp[2]; /* signal trampoline */
68 unsigned long tramp[2]; /* signal trampoline */
71 static int restore_sigcontext(struct pt_regs *regs,
72 struct sigcontext __user *sc, int *rval_p)
76 #define COPY(x) {err |= __get_user(regs->x, &sc->regs.x); }
79 COPY(r2); COPY(r3); COPY(r4); COPY(r5);
80 COPY(r6); COPY(r7); COPY(r8); COPY(r9);
81 COPY(r10); COPY(r11); COPY(r12); COPY(r13);
82 COPY(r14); COPY(r15); COPY(r16); COPY(r17);
83 COPY(r18); COPY(r19); COPY(r20); COPY(r21);
84 COPY(r22); COPY(r23); COPY(r24); COPY(r25);
85 COPY(r26); COPY(r27); COPY(r28); COPY(r29);
87 COPY(pc); COPY(ear); COPY(esr); COPY(fsr);
95 asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
97 struct rt_sigframe __user *frame =
98 (struct rt_sigframe __user *)(regs->r1 + STATE_SAVE_ARG_SPACE);
103 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
106 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
109 sigdelsetmask(&set, ~_BLOCKABLE);
110 spin_lock_irq(¤t->sighand->siglock);
111 current->blocked = set;
113 spin_unlock_irq(¤t->sighand->siglock);
115 if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &rval))
118 /* It is more difficult to avoid calling this function than to
119 call it and ignore errors. */
120 if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->r1))
126 force_sig(SIGSEGV, current);
131 * Set up a signal frame.
135 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
140 #define COPY(x) {err |= __put_user(regs->x, &sc->regs.x); }
143 COPY(r2); COPY(r3); COPY(r4); COPY(r5);
144 COPY(r6); COPY(r7); COPY(r8); COPY(r9);
145 COPY(r10); COPY(r11); COPY(r12); COPY(r13);
146 COPY(r14); COPY(r15); COPY(r16); COPY(r17);
147 COPY(r18); COPY(r19); COPY(r20); COPY(r21);
148 COPY(r22); COPY(r23); COPY(r24); COPY(r25);
149 COPY(r26); COPY(r27); COPY(r28); COPY(r29);
150 COPY(r30); COPY(r31);
151 COPY(pc); COPY(ear); COPY(esr); COPY(fsr);
154 err |= __put_user(mask, &sc->oldmask);
160 * Determine which stack to use..
162 static inline void __user *
163 get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
165 /* Default to using normal stack */
166 unsigned long sp = regs->r1;
168 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && !on_sig_stack(sp))
169 sp = current->sas_ss_sp + current->sas_ss_size;
171 return (void __user *)((sp - frame_size) & -8UL);
174 static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
175 sigset_t *set, struct pt_regs *regs)
177 struct rt_sigframe __user *frame;
181 frame = get_sigframe(ka, regs, sizeof(*frame));
183 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
186 signal = current_thread_info()->exec_domain
187 && current_thread_info()->exec_domain->signal_invmap
189 ? current_thread_info()->exec_domain->signal_invmap[sig]
193 err |= copy_siginfo_to_user(&frame->info, info);
195 /* Create the ucontext. */
196 err |= __put_user(0, &frame->uc.uc_flags);
197 err |= __put_user(0, &frame->uc.uc_link);
198 err |= __put_user((void *)current->sas_ss_sp,
199 &frame->uc.uc_stack.ss_sp);
200 err |= __put_user(sas_ss_flags(regs->r1),
201 &frame->uc.uc_stack.ss_flags);
202 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
203 err |= setup_sigcontext(&frame->uc.uc_mcontext,
205 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
207 /* Set up to return from userspace. If provided, use a stub
208 already in userspace. */
209 /* minus 8 is offset to cater for "rtsd r15,8" */
210 /* addi r12, r0, __NR_sigreturn */
211 err |= __put_user(0x31800000 | __NR_rt_sigreturn ,
214 err |= __put_user(0xb9cc0008, frame->tramp + 1);
216 /* Return from sighandler will jump to the tramp.
217 Negative 8 offset because return is rtsd r15, 8 */
218 regs->r15 = ((unsigned long)frame->tramp)-8;
220 __invalidate_cache_sigtramp((unsigned long)frame->tramp);
225 /* Set up registers for signal handler */
226 regs->r1 = (unsigned long) frame - STATE_SAVE_ARG_SPACE;
228 /* Signal handler args: */
229 regs->r5 = signal; /* arg 0: signum */
230 regs->r6 = (unsigned long) &frame->info; /* arg 1: siginfo */
231 regs->r7 = (unsigned long) &frame->uc; /* arg2: ucontext */
232 /* Offset to handle microblaze rtid r14, 0 */
233 regs->pc = (unsigned long)ka->sa.sa_handler;
238 printk(KERN_INFO "SIG deliver (%s:%d): sp=%p pc=%08lx\n",
239 current->comm, current->pid, frame, regs->pc);
246 ka->sa.sa_handler = SIG_DFL;
247 force_sig(SIGSEGV, current);
250 /* Handle restarting system calls */
252 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
255 case -ERESTART_RESTARTBLOCK:
256 case -ERESTARTNOHAND:
262 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
267 case -ERESTARTNOINTR:
269 /* offset of 4 bytes to re-execute trap (brki) instruction */
273 /* offset of 8 bytes required = 4 for rtbd
274 offset, plus 4 for size of
284 * OK, we're invoking a handler
288 handle_signal(unsigned long sig, struct k_sigaction *ka,
289 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
291 /* Set up the stack frame */
292 if (ka->sa.sa_flags & SA_SIGINFO)
293 setup_rt_frame(sig, ka, info, oldset, regs);
295 setup_rt_frame(sig, ka, NULL, oldset, regs);
297 if (ka->sa.sa_flags & SA_ONESHOT)
298 ka->sa.sa_handler = SIG_DFL;
300 if (!(ka->sa.sa_flags & SA_NODEFER)) {
301 spin_lock_irq(¤t->sighand->siglock);
302 sigorsets(¤t->blocked,
303 ¤t->blocked, &ka->sa.sa_mask);
304 sigaddset(¤t->blocked, sig);
306 spin_unlock_irq(¤t->sighand->siglock);
312 * Note that 'init' is a special process: it doesn't get signals it doesn't
313 * want to handle. Thus you cannot kill init even with a SIGKILL even by
316 * Note that we go through the signals twice: once to check the signals that
317 * the kernel can handle, and then we build all the user-level signal handling
318 * stack-frames in one go after that.
320 int do_signal(struct pt_regs *regs, sigset_t *oldset, int in_syscall)
324 struct k_sigaction ka;
326 printk(KERN_INFO "do signal: %p %p %d\n", regs, oldset, in_syscall);
327 printk(KERN_INFO "do signal2: %lx %lx %ld [%lx]\n", regs->pc, regs->r1,
328 regs->r12, current_thread_info()->flags);
331 * We want the common case to go fast, which
332 * is why we may in certain cases get here from
333 * kernel mode. Just return without doing anything
336 if (kernel_mode(regs))
339 if (current_thread_info()->status & TS_RESTORE_SIGMASK)
340 oldset = ¤t->saved_sigmask;
342 oldset = ¤t->blocked;
344 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
346 /* Whee! Actually deliver the signal. */
348 handle_restart(regs, &ka, 1);
349 if (handle_signal(signr, &ka, &info, oldset, regs)) {
351 * A signal was successfully delivered; the saved
352 * sigmask will have been stored in the signal frame,
353 * and will be restored by sigreturn, so we can simply
354 * clear the TS_RESTORE_SIGMASK flag.
356 current_thread_info()->status &=
363 handle_restart(regs, NULL, 0);
366 * If there's no signal to deliver, we just put the saved sigmask
369 if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
370 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
371 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
374 /* Did we come from a system call? */