arch/alpha/kernel/signal.c - LeafOS-Devices/android_kernel_samsung_universal7904 - Gitiles

 /*
  *  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);
 }
	/*
	* 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);
	}