summaryrefslogtreecommitdiff
path: root/arch/alpha/kernel/signal.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/alpha/kernel/signal.c
downloadconfigs-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/alpha/kernel/signal.c')
-rw-r--r--arch/alpha/kernel/signal.c672
1 files changed, 672 insertions, 0 deletions
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
new file mode 100644
index 00000000000..08fe8071a7f
--- /dev/null
+++ b/arch/alpha/kernel/signal.c
@@ -0,0 +1,672 @@
+/*
+ * linux/arch/alpha/kernel/signal.c
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ *
+ * 1997-11-02 Modified for POSIX.1b signals by Richard Henderson
+ */
+
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/unistd.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/stddef.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/bitops.h>
+
+#include <asm/uaccess.h>
+#include <asm/sigcontext.h>
+#include <asm/ucontext.h>
+
+#include "proto.h"
+
+
+#define DEBUG_SIG 0
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+asmlinkage void ret_from_sys_call(void);
+static int do_signal(sigset_t *, struct pt_regs *, struct switch_stack *,
+ unsigned long, unsigned long);
+
+
+/*
+ * The OSF/1 sigprocmask calling sequence is different from the
+ * C sigprocmask() sequence..
+ *
+ * how:
+ * 1 - SIG_BLOCK
+ * 2 - SIG_UNBLOCK
+ * 3 - SIG_SETMASK
+ *
+ * We change the range to -1 .. 1 in order to let gcc easily
+ * use the conditional move instructions.
+ *
+ * Note that we don't need to acquire the kernel lock for SMP
+ * operation, as all of this is local to this thread.
+ */
+asmlinkage unsigned long
+do_osf_sigprocmask(int how, unsigned long newmask, struct pt_regs *regs)
+{
+ unsigned long oldmask = -EINVAL;
+
+ if ((unsigned long)how-1 <= 2) {
+ long sign = how-2; /* -1 .. 1 */
+ unsigned long block, unblock;
+
+ newmask &= _BLOCKABLE;
+ spin_lock_irq(&current->sighand->siglock);
+ oldmask = current->blocked.sig[0];
+
+ unblock = oldmask & ~newmask;
+ block = oldmask | newmask;
+ if (!sign)
+ block = unblock;
+ if (sign <= 0)
+ newmask = block;
+ if (_NSIG_WORDS > 1 && sign > 0)
+ sigemptyset(&current->blocked);
+ current->blocked.sig[0] = newmask;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ regs->r0 = 0; /* special no error return */
+ }
+ return oldmask;
+}
+
+asmlinkage int
+osf_sigaction(int sig, const struct osf_sigaction __user *act,
+ struct osf_sigaction __user *oact)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+
+ if (act) {
+ old_sigset_t mask;
+ if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+ __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
+ __get_user(new_ka.sa.sa_flags, &act->sa_flags))
+ return -EFAULT;
+ __get_user(mask, &act->sa_mask);
+ siginitset(&new_ka.sa.sa_mask, mask);
+ new_ka.ka_restorer = NULL;
+ }
+
+ ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+
+ if (!ret && oact) {
+ if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+ __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
+ __put_user(old_ka.sa.sa_flags, &oact->sa_flags))
+ return -EFAULT;
+ __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
+ }
+
+ return ret;
+}
+
+asmlinkage long
+sys_rt_sigaction(int sig, const struct sigaction __user *act,
+ struct sigaction __user *oact,
+ size_t sigsetsize, void __user *restorer)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+
+ /* XXX: Don't preclude handling different sized sigset_t's. */
+ if (sigsetsize != sizeof(sigset_t))
+ return -EINVAL;
+
+ if (act) {
+ new_ka.ka_restorer = restorer;
+ if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
+ return -EFAULT;
+ }
+
+ ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+
+ if (!ret && oact) {
+ if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
+ return -EFAULT;
+ }
+
+ return ret;
+}
+
+/*
+ * Atomically swap in the new signal mask, and wait for a signal.
+ */
+asmlinkage int
+do_sigsuspend(old_sigset_t mask, struct pt_regs *regs, struct switch_stack *sw)
+{
+ sigset_t oldset;
+
+ mask &= _BLOCKABLE;
+ spin_lock_irq(&current->sighand->siglock);
+ oldset = current->blocked;
+ siginitset(&current->blocked, mask);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ /* Indicate EINTR on return from any possible signal handler,
+ which will not come back through here, but via sigreturn. */
+ regs->r0 = EINTR;
+ regs->r19 = 1;
+
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(&oldset, regs, sw, 0, 0))
+ return -EINTR;
+ }
+}
+
+asmlinkage int
+do_rt_sigsuspend(sigset_t __user *uset, size_t sigsetsize,
+ struct pt_regs *regs, struct switch_stack *sw)
+{
+ sigset_t oldset, set;
+
+ /* XXX: Don't preclude handling different sized sigset_t's. */
+ if (sigsetsize != sizeof(sigset_t))
+ return -EINVAL;
+ if (copy_from_user(&set, uset, sizeof(set)))
+ return -EFAULT;
+
+ sigdelsetmask(&set, ~_BLOCKABLE);
+ spin_lock_irq(&current->sighand->siglock);
+ oldset = current->blocked;
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ /* Indicate EINTR on return from any possible signal handler,
+ which will not come back through here, but via sigreturn. */
+ regs->r0 = EINTR;
+ regs->r19 = 1;
+
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(&oldset, regs, sw, 0, 0))
+ return -EINTR;
+ }
+}
+
+asmlinkage int
+sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
+{
+ return do_sigaltstack(uss, uoss, rdusp());
+}
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+
+#if _NSIG_WORDS > 1
+# error "Non SA_SIGINFO frame needs rearranging"
+#endif
+
+struct sigframe
+{
+ struct sigcontext sc;
+ unsigned int retcode[3];
+};
+
+struct rt_sigframe
+{
+ struct siginfo info;
+ struct ucontext uc;
+ unsigned int retcode[3];
+};
+
+/* If this changes, userland unwinders that Know Things about our signal
+ frame will break. Do not undertake lightly. It also implies an ABI
+ change wrt the size of siginfo_t, which may cause some pain. */
+extern char compile_time_assert
+ [offsetof(struct rt_sigframe, uc.uc_mcontext) == 176 ? 1 : -1];
+
+#define INSN_MOV_R30_R16 0x47fe0410
+#define INSN_LDI_R0 0x201f0000
+#define INSN_CALLSYS 0x00000083
+
+static long
+restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
+ struct switch_stack *sw)
+{
+ unsigned long usp;
+ long i, err = __get_user(regs->pc, &sc->sc_pc);
+
+ sw->r26 = (unsigned long) ret_from_sys_call;
+
+ err |= __get_user(regs->r0, sc->sc_regs+0);
+ err |= __get_user(regs->r1, sc->sc_regs+1);
+ err |= __get_user(regs->r2, sc->sc_regs+2);
+ err |= __get_user(regs->r3, sc->sc_regs+3);
+ err |= __get_user(regs->r4, sc->sc_regs+4);
+ err |= __get_user(regs->r5, sc->sc_regs+5);
+ err |= __get_user(regs->r6, sc->sc_regs+6);
+ err |= __get_user(regs->r7, sc->sc_regs+7);
+ err |= __get_user(regs->r8, sc->sc_regs+8);
+ err |= __get_user(sw->r9, sc->sc_regs+9);
+ err |= __get_user(sw->r10, sc->sc_regs+10);
+ err |= __get_user(sw->r11, sc->sc_regs+11);
+ err |= __get_user(sw->r12, sc->sc_regs+12);
+ err |= __get_user(sw->r13, sc->sc_regs+13);
+ err |= __get_user(sw->r14, sc->sc_regs+14);
+ err |= __get_user(sw->r15, sc->sc_regs+15);
+ err |= __get_user(regs->r16, sc->sc_regs+16);
+ err |= __get_user(regs->r17, sc->sc_regs+17);
+ err |= __get_user(regs->r18, sc->sc_regs+18);
+ err |= __get_user(regs->r19, sc->sc_regs+19);
+ err |= __get_user(regs->r20, sc->sc_regs+20);
+ err |= __get_user(regs->r21, sc->sc_regs+21);
+ err |= __get_user(regs->r22, sc->sc_regs+22);
+ err |= __get_user(regs->r23, sc->sc_regs+23);
+ err |= __get_user(regs->r24, sc->sc_regs+24);
+ err |= __get_user(regs->r25, sc->sc_regs+25);
+ err |= __get_user(regs->r26, sc->sc_regs+26);
+ err |= __get_user(regs->r27, sc->sc_regs+27);
+ err |= __get_user(regs->r28, sc->sc_regs+28);
+ err |= __get_user(regs->gp, sc->sc_regs+29);
+ err |= __get_user(usp, sc->sc_regs+30);
+ wrusp(usp);
+
+ for (i = 0; i < 31; i++)
+ err |= __get_user(sw->fp[i], sc->sc_fpregs+i);
+ err |= __get_user(sw->fp[31], &sc->sc_fpcr);
+
+ return err;
+}
+
+/* Note that this syscall is also used by setcontext(3) to install
+ a given sigcontext. This because it's impossible to set *all*
+ registers and transfer control from userland. */
+
+asmlinkage void
+do_sigreturn(struct sigcontext __user *sc, struct pt_regs *regs,
+ struct switch_stack *sw)
+{
+ sigset_t set;
+
+ /* Verify that it's a good sigcontext before using it */
+ if (!access_ok(VERIFY_READ, sc, sizeof(*sc)))
+ goto give_sigsegv;
+ if (__get_user(set.sig[0], &sc->sc_mask))
+ goto give_sigsegv;
+
+ sigdelsetmask(&set, ~_BLOCKABLE);
+ spin_lock_irq(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ if (restore_sigcontext(sc, regs, sw))
+ goto give_sigsegv;
+
+ /* Send SIGTRAP if we're single-stepping: */
+ if (ptrace_cancel_bpt (current)) {
+ siginfo_t info;
+
+ info.si_signo = SIGTRAP;
+ info.si_errno = 0;
+ info.si_code = TRAP_BRKPT;
+ info.si_addr = (void __user *) regs->pc;
+ info.si_trapno = 0;
+ send_sig_info(SIGTRAP, &info, current);
+ }
+ return;
+
+give_sigsegv:
+ force_sig(SIGSEGV, current);
+}
+
+asmlinkage void
+do_rt_sigreturn(struct rt_sigframe __user *frame, struct pt_regs *regs,
+ struct switch_stack *sw)
+{
+ sigset_t set;
+
+ /* Verify that it's a good ucontext_t before using it */
+ if (!access_ok(VERIFY_READ, &frame->uc, sizeof(frame->uc)))
+ goto give_sigsegv;
+ if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+ goto give_sigsegv;
+
+ sigdelsetmask(&set, ~_BLOCKABLE);
+ spin_lock_irq(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ if (restore_sigcontext(&frame->uc.uc_mcontext, regs, sw))
+ goto give_sigsegv;
+
+ /* Send SIGTRAP if we're single-stepping: */
+ if (ptrace_cancel_bpt (current)) {
+ siginfo_t info;
+
+ info.si_signo = SIGTRAP;
+ info.si_errno = 0;
+ info.si_code = TRAP_BRKPT;
+ info.si_addr = (void __user *) regs->pc;
+ info.si_trapno = 0;
+ send_sig_info(SIGTRAP, &info, current);
+ }
+ return;
+
+give_sigsegv:
+ force_sig(SIGSEGV, current);
+}
+
+
+/*
+ * Set up a signal frame.
+ */
+
+static inline void __user *
+get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
+{
+ if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp))
+ sp = current->sas_ss_sp + current->sas_ss_size;
+
+ return (void __user *)((sp - frame_size) & -32ul);
+}
+
+static long
+setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
+ struct switch_stack *sw, unsigned long mask, unsigned long sp)
+{
+ long i, err = 0;
+
+ err |= __put_user(on_sig_stack((unsigned long)sc), &sc->sc_onstack);
+ err |= __put_user(mask, &sc->sc_mask);
+ err |= __put_user(regs->pc, &sc->sc_pc);
+ err |= __put_user(8, &sc->sc_ps);
+
+ err |= __put_user(regs->r0 , sc->sc_regs+0);
+ err |= __put_user(regs->r1 , sc->sc_regs+1);
+ err |= __put_user(regs->r2 , sc->sc_regs+2);
+ err |= __put_user(regs->r3 , sc->sc_regs+3);
+ err |= __put_user(regs->r4 , sc->sc_regs+4);
+ err |= __put_user(regs->r5 , sc->sc_regs+5);
+ err |= __put_user(regs->r6 , sc->sc_regs+6);
+ err |= __put_user(regs->r7 , sc->sc_regs+7);
+ err |= __put_user(regs->r8 , sc->sc_regs+8);
+ err |= __put_user(sw->r9 , sc->sc_regs+9);
+ err |= __put_user(sw->r10 , sc->sc_regs+10);
+ err |= __put_user(sw->r11 , sc->sc_regs+11);
+ err |= __put_user(sw->r12 , sc->sc_regs+12);
+ err |= __put_user(sw->r13 , sc->sc_regs+13);
+ err |= __put_user(sw->r14 , sc->sc_regs+14);
+ err |= __put_user(sw->r15 , sc->sc_regs+15);
+ err |= __put_user(regs->r16, sc->sc_regs+16);
+ err |= __put_user(regs->r17, sc->sc_regs+17);
+ err |= __put_user(regs->r18, sc->sc_regs+18);
+ err |= __put_user(regs->r19, sc->sc_regs+19);
+ err |= __put_user(regs->r20, sc->sc_regs+20);
+ err |= __put_user(regs->r21, sc->sc_regs+21);
+ err |= __put_user(regs->r22, sc->sc_regs+22);
+ err |= __put_user(regs->r23, sc->sc_regs+23);
+ err |= __put_user(regs->r24, sc->sc_regs+24);
+ err |= __put_user(regs->r25, sc->sc_regs+25);
+ err |= __put_user(regs->r26, sc->sc_regs+26);
+ err |= __put_user(regs->r27, sc->sc_regs+27);
+ err |= __put_user(regs->r28, sc->sc_regs+28);
+ err |= __put_user(regs->gp , sc->sc_regs+29);
+ err |= __put_user(sp, sc->sc_regs+30);
+ err |= __put_user(0, sc->sc_regs+31);
+
+ for (i = 0; i < 31; i++)
+ err |= __put_user(sw->fp[i], sc->sc_fpregs+i);
+ err |= __put_user(0, sc->sc_fpregs+31);
+ err |= __put_user(sw->fp[31], &sc->sc_fpcr);
+
+ err |= __put_user(regs->trap_a0, &sc->sc_traparg_a0);
+ err |= __put_user(regs->trap_a1, &sc->sc_traparg_a1);
+ err |= __put_user(regs->trap_a2, &sc->sc_traparg_a2);
+
+ return err;
+}
+
+static void
+setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
+ struct pt_regs *regs, struct switch_stack * sw)
+{
+ unsigned long oldsp, r26, err = 0;
+ struct sigframe __user *frame;
+
+ oldsp = rdusp();
+ frame = get_sigframe(ka, oldsp, sizeof(*frame));
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ goto give_sigsegv;
+
+ err |= setup_sigcontext(&frame->sc, regs, sw, set->sig[0], oldsp);
+ if (err)
+ goto give_sigsegv;
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ if (ka->ka_restorer) {
+ r26 = (unsigned long) ka->ka_restorer;
+ } else {
+ err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
+ err |= __put_user(INSN_LDI_R0+__NR_sigreturn, frame->retcode+1);
+ err |= __put_user(INSN_CALLSYS, frame->retcode+2);
+ imb();
+ r26 = (unsigned long) frame->retcode;
+ }
+
+ /* Check that everything was written properly. */
+ if (err)
+ goto give_sigsegv;
+
+ /* "Return" to the handler */
+ regs->r26 = r26;
+ regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
+ regs->r16 = sig; /* a0: signal number */
+ regs->r17 = 0; /* a1: exception code */
+ regs->r18 = (unsigned long) &frame->sc; /* a2: sigcontext pointer */
+ wrusp((unsigned long) frame);
+
+#if DEBUG_SIG
+ printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
+ current->comm, current->pid, frame, regs->pc, regs->r26);
+#endif
+
+ return;
+
+give_sigsegv:
+ force_sigsegv(sig, current);
+}
+
+static void
+setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs *regs, struct switch_stack * sw)
+{
+ unsigned long oldsp, r26, err = 0;
+ struct rt_sigframe __user *frame;
+
+ oldsp = rdusp();
+ frame = get_sigframe(ka, oldsp, sizeof(*frame));
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ goto give_sigsegv;
+
+ err |= copy_siginfo_to_user(&frame->info, info);
+
+ /* Create the ucontext. */
+ err |= __put_user(0, &frame->uc.uc_flags);
+ err |= __put_user(0, &frame->uc.uc_link);
+ err |= __put_user(set->sig[0], &frame->uc.uc_osf_sigmask);
+ err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
+ err |= __put_user(sas_ss_flags(oldsp), &frame->uc.uc_stack.ss_flags);
+ err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, sw,
+ set->sig[0], oldsp);
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+ if (err)
+ goto give_sigsegv;
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ if (ka->ka_restorer) {
+ r26 = (unsigned long) ka->ka_restorer;
+ } else {
+ err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
+ err |= __put_user(INSN_LDI_R0+__NR_rt_sigreturn,
+ frame->retcode+1);
+ err |= __put_user(INSN_CALLSYS, frame->retcode+2);
+ imb();
+ r26 = (unsigned long) frame->retcode;
+ }
+
+ if (err)
+ goto give_sigsegv;
+
+ /* "Return" to the handler */
+ regs->r26 = r26;
+ regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
+ regs->r16 = sig; /* a0: signal number */
+ regs->r17 = (unsigned long) &frame->info; /* a1: siginfo pointer */
+ regs->r18 = (unsigned long) &frame->uc; /* a2: ucontext pointer */
+ wrusp((unsigned long) frame);
+
+#if DEBUG_SIG
+ printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
+ current->comm, current->pid, frame, regs->pc, regs->r26);
+#endif
+
+ return;
+
+give_sigsegv:
+ force_sigsegv(sig, current);
+}
+
+
+/*
+ * OK, we're invoking a handler.
+ */
+static inline void
+handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *oldset, struct pt_regs * regs, struct switch_stack *sw)
+{
+ if (ka->sa.sa_flags & SA_SIGINFO)
+ setup_rt_frame(sig, ka, info, oldset, regs, sw);
+ else
+ setup_frame(sig, ka, oldset, regs, sw);
+
+ if (ka->sa.sa_flags & SA_RESETHAND)
+ ka->sa.sa_handler = SIG_DFL;
+
+ if (!(ka->sa.sa_flags & SA_NODEFER)) {
+ spin_lock_irq(&current->sighand->siglock);
+ sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+ sigaddset(&current->blocked,sig);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+ }
+}
+
+static inline void
+syscall_restart(unsigned long r0, unsigned long r19,
+ struct pt_regs *regs, struct k_sigaction *ka)
+{
+ switch (regs->r0) {
+ case ERESTARTSYS:
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ case ERESTARTNOHAND:
+ regs->r0 = EINTR;
+ break;
+ }
+ /* fallthrough */
+ case ERESTARTNOINTR:
+ regs->r0 = r0; /* reset v0 and a3 and replay syscall */
+ regs->r19 = r19;
+ regs->pc -= 4;
+ break;
+ case ERESTART_RESTARTBLOCK:
+ current_thread_info()->restart_block.fn = do_no_restart_syscall;
+ regs->r0 = EINTR;
+ break;
+ }
+}
+
+
+/*
+ * Note that 'init' is a special process: it doesn't get signals it doesn't
+ * want to handle. Thus you cannot kill init even with a SIGKILL even by
+ * mistake.
+ *
+ * Note that we go through the signals twice: once to check the signals that
+ * the kernel can handle, and then we build all the user-level signal handling
+ * stack-frames in one go after that.
+ *
+ * "r0" and "r19" are the registers we need to restore for system call
+ * restart. "r0" is also used as an indicator whether we can restart at
+ * all (if we get here from anything but a syscall return, it will be 0)
+ */
+static int
+do_signal(sigset_t *oldset, struct pt_regs * regs, struct switch_stack * sw,
+ unsigned long r0, unsigned long r19)
+{
+ siginfo_t info;
+ int signr;
+ unsigned long single_stepping = ptrace_cancel_bpt(current);
+ struct k_sigaction ka;
+
+ if (!oldset)
+ oldset = &current->blocked;
+
+ /* This lets the debugger run, ... */
+ signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+ /* ... so re-check the single stepping. */
+ single_stepping |= ptrace_cancel_bpt(current);
+
+ if (signr > 0) {
+ /* Whee! Actually deliver the signal. */
+ if (r0) syscall_restart(r0, r19, regs, &ka);
+ handle_signal(signr, &ka, &info, oldset, regs, sw);
+ if (single_stepping)
+ ptrace_set_bpt(current); /* re-set bpt */
+ return 1;
+ }
+
+ if (r0) {
+ switch (regs->r0) {
+ case ERESTARTNOHAND:
+ case ERESTARTSYS:
+ case ERESTARTNOINTR:
+ /* Reset v0 and a3 and replay syscall. */
+ regs->r0 = r0;
+ regs->r19 = r19;
+ regs->pc -= 4;
+ break;
+ case ERESTART_RESTARTBLOCK:
+ /* Force v0 to the restart syscall and reply. */
+ regs->r0 = __NR_restart_syscall;
+ regs->pc -= 4;
+ break;
+ }
+ }
+ if (single_stepping)
+ ptrace_set_bpt(current); /* re-set breakpoint */
+
+ return 0;
+}
+
+void
+do_notify_resume(sigset_t *oldset, struct pt_regs *regs,
+ struct switch_stack *sw, unsigned long r0,
+ unsigned long r19, unsigned long thread_info_flags)
+{
+ if (thread_info_flags & _TIF_SIGPENDING)
+ do_signal(oldset, regs, sw, r0, r19);
+}