arch/mn10300/kernel/signal.c - arm/linux - Git at Google

 /* MN10300 Signal handling
  *
  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public Licence
  * as published by the Free Software Foundation; either version
  * 2 of the Licence, or (at your option) any later version.
  */

 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/smp.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/stddef.h>
 #include <linux/tty.h>
 #include <linux/personality.h>
 #include <linux/suspend.h>
 #include <linux/tracehook.h>
 #include <asm/cacheflush.h>
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
 #include <asm/fpu.h>
 #include "sigframe.h"

 #define DEBUG_SIG 0

 /*
  * do a signal return; undo the signal stack.
  */
 static int restore_sigcontext(struct pt_regs *regs,
 			      struct sigcontext __user *sc, long *_d0)
 {
 	unsigned int err = 0;

 	/* Always make any pending restarted system calls return -EINTR */
 	current->restart_block.fn = do_no_restart_syscall;

 	if (is_using_fpu(current))
 		fpu_kill_state(current);

 #define COPY(x) err |= __get_user(regs->x, &sc->x)
 	COPY(d1); COPY(d2); COPY(d3);
 	COPY(a0); COPY(a1); COPY(a2); COPY(a3);
 	COPY(e0); COPY(e1); COPY(e2); COPY(e3);
 	COPY(e4); COPY(e5); COPY(e6); COPY(e7);
 	COPY(lar); COPY(lir);
 	COPY(mdr); COPY(mdrq);
 	COPY(mcvf); COPY(mcrl); COPY(mcrh);
 	COPY(sp); COPY(pc);
 #undef COPY

 	{
 		unsigned int tmpflags;
 #ifndef CONFIG_MN10300_USING_JTAG
 #define USER_EPSW (EPSW_FLAG_Z | EPSW_FLAG_N | EPSW_FLAG_C | EPSW_FLAG_V | \
 		   EPSW_T | EPSW_nAR)
 #else
 #define USER_EPSW (EPSW_FLAG_Z | EPSW_FLAG_N | EPSW_FLAG_C | EPSW_FLAG_V | \
 		   EPSW_nAR)
 #endif
 		err |= __get_user(tmpflags, &sc->epsw);
 		regs->epsw = (regs->epsw & ~USER_EPSW) |
 		  (tmpflags & USER_EPSW);
 		regs->orig_d0 = -1;		/* disable syscall checks */
 	}

 	{
 		struct fpucontext *buf;
 		err |= __get_user(buf, &sc->fpucontext);
 		if (buf) {
 			if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
 				goto badframe;
 			err |= fpu_restore_sigcontext(buf);
 		}
 	}

 	err |= __get_user(*_d0, &sc->d0);
 	return err;

 badframe:
 	return 1;
 }

 /*
  * standard signal return syscall
  */
 asmlinkage long sys_sigreturn(void)
 {
 	struct sigframe __user *frame;
 	sigset_t set;
 	long d0;

 	frame = (struct sigframe __user *) current_frame()->sp;
 	if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
 		goto badframe;
 	if (__get_user(set.sig[0], &frame->sc.oldmask))
 		goto badframe;

 	if (_NSIG_WORDS > 1 &&
 	    __copy_from_user(&set.sig[1], &frame->extramask,
 			     sizeof(frame->extramask)))
 		goto badframe;

 	set_current_blocked(&set);

 	if (restore_sigcontext(current_frame(), &frame->sc, &d0))
 		goto badframe;

 	return d0;

 badframe:
 	force_sig(SIGSEGV, current);
 	return 0;
 }

 /*
  * realtime signal return syscall
  */
 asmlinkage long sys_rt_sigreturn(void)
 {
 	struct rt_sigframe __user *frame;
 	sigset_t set;
 	long d0;

 	frame = (struct rt_sigframe __user *) current_frame()->sp;
 	if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
 		goto badframe;
 	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
 		goto badframe;

 	set_current_blocked(&set);

 	if (restore_sigcontext(current_frame(), &frame->uc.uc_mcontext, &d0))
 		goto badframe;

 	if (restore_altstack(&frame->uc.uc_stack))
 		goto badframe;

 	return d0;

 badframe:
 	force_sig(SIGSEGV, current);
 	return 0;
 }

 /*
  * store the userspace context into a signal frame
  */
 static int setup_sigcontext(struct sigcontext __user *sc,
 			    struct fpucontext *fpuctx,
 			    struct pt_regs *regs,
 			    unsigned long mask)
 {
 	int tmp, err = 0;

 #define COPY(x) err |= __put_user(regs->x, &sc->x)
 	COPY(d0); COPY(d1); COPY(d2); COPY(d3);
 	COPY(a0); COPY(a1); COPY(a2); COPY(a3);
 	COPY(e0); COPY(e1); COPY(e2); COPY(e3);
 	COPY(e4); COPY(e5); COPY(e6); COPY(e7);
 	COPY(lar); COPY(lir);
 	COPY(mdr); COPY(mdrq);
 	COPY(mcvf); COPY(mcrl); COPY(mcrh);
 	COPY(sp); COPY(epsw); COPY(pc);
 #undef COPY

 	tmp = fpu_setup_sigcontext(fpuctx);
 	if (tmp < 0)
 		err = 1;
 	else
 		err |= __put_user(tmp ? fpuctx : NULL, &sc->fpucontext);

 	/* non-iBCS2 extensions.. */
 	err |= __put_user(mask, &sc->oldmask);

 	return err;
 }

 /*
  * determine which stack to use..
  */
 static inline void __user *get_sigframe(struct ksignal *ksig,
 					struct pt_regs *regs,
 					size_t frame_size)
 {
 	unsigned long sp = sigsp(regs->sp, ksig);

 	return (void __user *) ((sp - frame_size) & ~7UL);
 }

 /*
  * set up a normal signal frame
  */
 static int setup_frame(struct ksignal *ksig, sigset_t *set,
 		       struct pt_regs *regs)
 {
 	struct sigframe __user *frame;
 	int sig = ksig->sig;

 	frame = get_sigframe(ksig, regs, sizeof(*frame));

 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		return -EFAULT;

 	if (__put_user(sig, &frame->sig) < 0 ||
 	    __put_user(&frame->sc, &frame->psc) < 0)
 		return -EFAULT;

 	if (setup_sigcontext(&frame->sc, &frame->fpuctx, regs, set->sig[0]))
 		return -EFAULT;

 	if (_NSIG_WORDS > 1) {
 		if (__copy_to_user(frame->extramask, &set->sig[1],
 				   sizeof(frame->extramask)))
 			return -EFAULT;
 	}

 	/* set up to return from userspace.  If provided, use a stub already in
 	 * userspace */
 	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
 		if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
 			return -EFAULT;
 	} else {
 		if (__put_user((void (*)(void))frame->retcode,
 			       &frame->pretcode))
 			return -EFAULT;
 		/* this is mov $,d0; syscall 0 */
 		if (__put_user(0x2c, (char *)(frame->retcode + 0)) ||
 		    __put_user(__NR_sigreturn, (char *)(frame->retcode + 1)) ||
 		    __put_user(0x00, (char *)(frame->retcode + 2)) ||
 		    __put_user(0xf0, (char *)(frame->retcode + 3)) ||
 		    __put_user(0xe0, (char *)(frame->retcode + 4)))
 			return -EFAULT;
 		flush_icache_range((unsigned long) frame->retcode,
 				   (unsigned long) frame->retcode + 5);
 	}

 	/* set up registers for signal handler */
 	regs->sp = (unsigned long) frame;
 	regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
 	regs->d0 = sig;
 	regs->d1 = (unsigned long) &frame->sc;

 #if DEBUG_SIG
 	printk(KERN_DEBUG "SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
 	       sig, current->comm, current->pid, frame, regs->pc,
 	       frame->pretcode);
 #endif

 	return 0;
 }

 /*
  * set up a realtime signal frame
  */
 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
 			  struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
 	int sig = ksig->sig;

 	frame = get_sigframe(ksig, regs, sizeof(*frame));

 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		return -EFAULT;

 	if (__put_user(sig, &frame->sig) ||
 	    __put_user(&frame->info, &frame->pinfo) ||
 	    __put_user(&frame->uc, &frame->puc) ||
 	    copy_siginfo_to_user(&frame->info, &ksig->info))
 		return -EFAULT;

 	/* create the ucontext.  */
 	if (__put_user(0, &frame->uc.uc_flags) ||
 	    __put_user(0, &frame->uc.uc_link) ||
 	    __save_altstack(&frame->uc.uc_stack, regs->sp) ||
 	    setup_sigcontext(&frame->uc.uc_mcontext,
 			     &frame->fpuctx, regs, set->sig[0]) ||
 	    __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
 		return -EFAULT;

 	/* set up to return from userspace.  If provided, use a stub already in
 	 * userspace */
 	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
 		if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
 			return -EFAULT;

 	} else {
 		if (__put_user((void(*)(void))frame->retcode,
 			       &frame->pretcode) ||
 		    /* This is mov $,d0; syscall 0 */
 		    __put_user(0x2c, (char *)(frame->retcode + 0)) ||
 		    __put_user(__NR_rt_sigreturn,
 			       (char *)(frame->retcode + 1)) ||
 		    __put_user(0x00, (char *)(frame->retcode + 2)) ||
 		    __put_user(0xf0, (char *)(frame->retcode + 3)) ||
 		    __put_user(0xe0, (char *)(frame->retcode + 4)))
 			return -EFAULT;

 		flush_icache_range((u_long) frame->retcode,
 				   (u_long) frame->retcode + 5);
 	}

 	/* Set up registers for signal handler */
 	regs->sp = (unsigned long) frame;
 	regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
 	regs->d0 = sig;
 	regs->d1 = (long) &frame->info;

 #if DEBUG_SIG
 	printk(KERN_DEBUG "SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
 	       sig, current->comm, current->pid, frame, regs->pc,
 	       frame->pretcode);
 #endif

 	return 0;
 }

 static inline void stepback(struct pt_regs *regs)
 {
 	regs->pc -= 2;
 	regs->orig_d0 = -1;
 }

 /*
  * handle the actual delivery of a signal to userspace
  */
 static int handle_signal(struct ksignal *ksig, struct pt_regs *regs)
 {
 	sigset_t *oldset = sigmask_to_save();
 	int ret;

 	/* Are we from a system call? */
 	if (regs->orig_d0 >= 0) {
 		/* If so, check system call restarting.. */
 		switch (regs->d0) {
 		case -ERESTART_RESTARTBLOCK:
 		case -ERESTARTNOHAND:
 			regs->d0 = -EINTR;
 			break;

 		case -ERESTARTSYS:
 			if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
 				regs->d0 = -EINTR;
 				break;
 			}

 			/* fallthrough */
 		case -ERESTARTNOINTR:
 			regs->d0 = regs->orig_d0;
 			stepback(regs);
 		}
 	}

 	/* Set up the stack frame */
 	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
 		ret = setup_rt_frame(ksig, oldset, regs);
 	else
 		ret = setup_frame(ksig, oldset, regs);

 	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
 	return 0;
 }

 /*
  * handle a potential signal
  */
 static void do_signal(struct pt_regs *regs)
 {
 	struct ksignal ksig;

 	if (get_signal(&ksig)) {
 		handle_signal(&ksig, regs);
 		return;
 	}

 	/* did we come from a system call? */
 	if (regs->orig_d0 >= 0) {
 		/* restart the system call - no handlers present */
 		switch (regs->d0) {
 		case -ERESTARTNOHAND:
 		case -ERESTARTSYS:
 		case -ERESTARTNOINTR:
 			regs->d0 = regs->orig_d0;
 			stepback(regs);
 			break;

 		case -ERESTART_RESTARTBLOCK:
 			regs->d0 = __NR_restart_syscall;
 			stepback(regs);
 			break;
 		}
 	}

 	/* if there's no signal to deliver, we just put the saved sigmask
 	 * back */
 	restore_saved_sigmask();
 }

 /*
  * notification of userspace execution resumption
  * - triggered by current->work.notify_resume
  */
 asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)
 {
 	/* Pending single-step? */
 	if (thread_info_flags & _TIF_SINGLESTEP) {
 #ifndef CONFIG_MN10300_USING_JTAG
 		regs->epsw |= EPSW_T;
 		clear_thread_flag(TIF_SINGLESTEP);
 #else
 		BUG(); /* no h/w single-step if using JTAG unit */
 #endif
 	}

 	/* deal with pending signal delivery */
 	if (thread_info_flags & _TIF_SIGPENDING)
 		do_signal(regs);

 	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
 		clear_thread_flag(TIF_NOTIFY_RESUME);
 		tracehook_notify_resume(current_frame());
 	}
 }
	/* MN10300 Signal handling
	*
	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	* Written by David Howells (dhowells@redhat.com)
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public Licence
	* as published by the Free Software Foundation; either version
	* 2 of the Licence, or (at your option) any later version.
	*/

	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/smp.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/stddef.h>
	#include <linux/tty.h>
	#include <linux/personality.h>
	#include <linux/suspend.h>
	#include <linux/tracehook.h>
	#include <asm/cacheflush.h>
	#include <asm/ucontext.h>
	#include <asm/uaccess.h>
	#include <asm/fpu.h>
	#include "sigframe.h"

	#define DEBUG_SIG 0

	/*
	* do a signal return; undo the signal stack.
	*/
	static int restore_sigcontext(struct pt_regs *regs,
	struct sigcontext __user sc, long _d0)
	{
	unsigned int err = 0;

	/* Always make any pending restarted system calls return -EINTR */
	current->restart_block.fn = do_no_restart_syscall;

	if (is_using_fpu(current))
	fpu_kill_state(current);

	#define COPY(x) err \|= __get_user(regs->x, &sc->x)
	COPY(d1); COPY(d2); COPY(d3);
	COPY(a0); COPY(a1); COPY(a2); COPY(a3);
	COPY(e0); COPY(e1); COPY(e2); COPY(e3);
	COPY(e4); COPY(e5); COPY(e6); COPY(e7);
	COPY(lar); COPY(lir);
	COPY(mdr); COPY(mdrq);
	COPY(mcvf); COPY(mcrl); COPY(mcrh);
	COPY(sp); COPY(pc);
	#undef COPY

	{
	unsigned int tmpflags;
	#ifndef CONFIG_MN10300_USING_JTAG
	#define USER_EPSW (EPSW_FLAG_Z \| EPSW_FLAG_N \| EPSW_FLAG_C \| EPSW_FLAG_V \| \
	EPSW_T \| EPSW_nAR)
	#else
	#define USER_EPSW (EPSW_FLAG_Z \| EPSW_FLAG_N \| EPSW_FLAG_C \| EPSW_FLAG_V \| \
	EPSW_nAR)
	#endif
	err \|= __get_user(tmpflags, &sc->epsw);
	regs->epsw = (regs->epsw & ~USER_EPSW) \|
	(tmpflags & USER_EPSW);
	regs->orig_d0 = -1; /* disable syscall checks */
	}

	{
	struct fpucontext *buf;
	err \|= __get_user(buf, &sc->fpucontext);
	if (buf) {
	if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
	goto badframe;
	err \|= fpu_restore_sigcontext(buf);
	}
	}

	err \|= __get_user(*_d0, &sc->d0);
	return err;

	badframe:
	return 1;
	}

	/*
	* standard signal return syscall
	*/
	asmlinkage long sys_sigreturn(void)
	{
	struct sigframe __user *frame;
	sigset_t set;
	long d0;

	frame = (struct sigframe __user *) current_frame()->sp;
	if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
	goto badframe;
	if (__get_user(set.sig[0], &frame->sc.oldmask))
	goto badframe;

	if (_NSIG_WORDS > 1 &&
	__copy_from_user(&set.sig[1], &frame->extramask,
	sizeof(frame->extramask)))
	goto badframe;

	set_current_blocked(&set);

	if (restore_sigcontext(current_frame(), &frame->sc, &d0))
	goto badframe;

	return d0;

	badframe:
	force_sig(SIGSEGV, current);
	return 0;
	}

	/*
	* realtime signal return syscall
	*/
	asmlinkage long sys_rt_sigreturn(void)
	{
	struct rt_sigframe __user *frame;
	sigset_t set;
	long d0;

	frame = (struct rt_sigframe __user *) current_frame()->sp;
	if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
	goto badframe;
	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
	goto badframe;

	set_current_blocked(&set);

	if (restore_sigcontext(current_frame(), &frame->uc.uc_mcontext, &d0))
	goto badframe;

	if (restore_altstack(&frame->uc.uc_stack))
	goto badframe;

	return d0;

	badframe:
	force_sig(SIGSEGV, current);
	return 0;
	}

	/*
	* store the userspace context into a signal frame
	*/
	static int setup_sigcontext(struct sigcontext __user *sc,
	struct fpucontext *fpuctx,
	struct pt_regs *regs,
	unsigned long mask)
	{
	int tmp, err = 0;

	#define COPY(x) err \|= __put_user(regs->x, &sc->x)
	COPY(d0); COPY(d1); COPY(d2); COPY(d3);
	COPY(a0); COPY(a1); COPY(a2); COPY(a3);
	COPY(e0); COPY(e1); COPY(e2); COPY(e3);
	COPY(e4); COPY(e5); COPY(e6); COPY(e7);
	COPY(lar); COPY(lir);
	COPY(mdr); COPY(mdrq);
	COPY(mcvf); COPY(mcrl); COPY(mcrh);
	COPY(sp); COPY(epsw); COPY(pc);
	#undef COPY

	tmp = fpu_setup_sigcontext(fpuctx);
	if (tmp < 0)
	err = 1;
	else
	err \|= __put_user(tmp ? fpuctx : NULL, &sc->fpucontext);

	/* non-iBCS2 extensions.. */
	err \|= __put_user(mask, &sc->oldmask);

	return err;
	}

	/*
	* determine which stack to use..
	*/
	static inline void __user get_sigframe(struct ksignal ksig,
	struct pt_regs *regs,
	size_t frame_size)
	{
	unsigned long sp = sigsp(regs->sp, ksig);

	return (void __user *) ((sp - frame_size) & ~7UL);
	}

	/*
	* set up a normal signal frame
	*/
	static int setup_frame(struct ksignal ksig, sigset_t set,
	struct pt_regs *regs)
	{
	struct sigframe __user *frame;
	int sig = ksig->sig;

	frame = get_sigframe(ksig, regs, sizeof(*frame));

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	return -EFAULT;

	if (__put_user(sig, &frame->sig) < 0 \|\|
	__put_user(&frame->sc, &frame->psc) < 0)
	return -EFAULT;

	if (setup_sigcontext(&frame->sc, &frame->fpuctx, regs, set->sig[0]))
	return -EFAULT;

	if (_NSIG_WORDS > 1) {
	if (__copy_to_user(frame->extramask, &set->sig[1],
	sizeof(frame->extramask)))
	return -EFAULT;
	}

	/* set up to return from userspace. If provided, use a stub already in
	* userspace */
	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
	if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
	return -EFAULT;
	} else {
	if (__put_user((void (*)(void))frame->retcode,
	&frame->pretcode))
	return -EFAULT;
	/* this is mov $,d0; syscall 0 */
	if (__put_user(0x2c, (char *)(frame->retcode + 0)) \|\|
	__put_user(__NR_sigreturn, (char *)(frame->retcode + 1)) \|\|
	__put_user(0x00, (char *)(frame->retcode + 2)) \|\|
	__put_user(0xf0, (char *)(frame->retcode + 3)) \|\|
	__put_user(0xe0, (char *)(frame->retcode + 4)))
	return -EFAULT;
	flush_icache_range((unsigned long) frame->retcode,
	(unsigned long) frame->retcode + 5);
	}

	/* set up registers for signal handler */
	regs->sp = (unsigned long) frame;
	regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
	regs->d0 = sig;
	regs->d1 = (unsigned long) &frame->sc;

	#if DEBUG_SIG
	printk(KERN_DEBUG "SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
	sig, current->comm, current->pid, frame, regs->pc,
	frame->pretcode);
	#endif

	return 0;
	}

	/*
	* set up a realtime signal frame
	*/
	static int setup_rt_frame(struct ksignal ksig, sigset_t set,
	struct pt_regs *regs)
	{
	struct rt_sigframe __user *frame;
	int sig = ksig->sig;

	frame = get_sigframe(ksig, regs, sizeof(*frame));

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	return -EFAULT;

	if (__put_user(sig, &frame->sig) \|\|
	__put_user(&frame->info, &frame->pinfo) \|\|
	__put_user(&frame->uc, &frame->puc) \|\|
	copy_siginfo_to_user(&frame->info, &ksig->info))
	return -EFAULT;

	/* create the ucontext. */
	if (__put_user(0, &frame->uc.uc_flags) \|\|
	__put_user(0, &frame->uc.uc_link) \|\|
	__save_altstack(&frame->uc.uc_stack, regs->sp) \|\|
	setup_sigcontext(&frame->uc.uc_mcontext,
	&frame->fpuctx, regs, set->sig[0]) \|\|
	__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
	return -EFAULT;

	/* set up to return from userspace. If provided, use a stub already in
	* userspace */
	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
	if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
	return -EFAULT;

	} else {
	if (__put_user((void(*)(void))frame->retcode,
	&frame->pretcode) \|\|
	/* This is mov $,d0; syscall 0 */
	__put_user(0x2c, (char *)(frame->retcode + 0)) \|\|
	__put_user(__NR_rt_sigreturn,
	(char *)(frame->retcode + 1)) \|\|
	__put_user(0x00, (char *)(frame->retcode + 2)) \|\|
	__put_user(0xf0, (char *)(frame->retcode + 3)) \|\|
	__put_user(0xe0, (char *)(frame->retcode + 4)))
	return -EFAULT;

	flush_icache_range((u_long) frame->retcode,
	(u_long) frame->retcode + 5);
	}

	/* Set up registers for signal handler */
	regs->sp = (unsigned long) frame;
	regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
	regs->d0 = sig;
	regs->d1 = (long) &frame->info;

	#if DEBUG_SIG
	printk(KERN_DEBUG "SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
	sig, current->comm, current->pid, frame, regs->pc,
	frame->pretcode);
	#endif

	return 0;
	}

	static inline void stepback(struct pt_regs *regs)
	{
	regs->pc -= 2;
	regs->orig_d0 = -1;
	}

	/*
	* handle the actual delivery of a signal to userspace
	*/
	static int handle_signal(struct ksignal ksig, struct pt_regs regs)
	{
	sigset_t *oldset = sigmask_to_save();
	int ret;

	/* Are we from a system call? */
	if (regs->orig_d0 >= 0) {
	/* If so, check system call restarting.. */
	switch (regs->d0) {
	case -ERESTART_RESTARTBLOCK:
	case -ERESTARTNOHAND:
	regs->d0 = -EINTR;
	break;

	case -ERESTARTSYS:
	if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
	regs->d0 = -EINTR;
	break;
	}

	/* fallthrough */
	case -ERESTARTNOINTR:
	regs->d0 = regs->orig_d0;
	stepback(regs);
	}
	}

	/* Set up the stack frame */
	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
	ret = setup_rt_frame(ksig, oldset, regs);
	else
	ret = setup_frame(ksig, oldset, regs);

	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
	return 0;
	}

	/*
	* handle a potential signal
	*/
	static void do_signal(struct pt_regs *regs)
	{
	struct ksignal ksig;

	if (get_signal(&ksig)) {
	handle_signal(&ksig, regs);
	return;
	}

	/* did we come from a system call? */
	if (regs->orig_d0 >= 0) {
	/* restart the system call - no handlers present */
	switch (regs->d0) {
	case -ERESTARTNOHAND:
	case -ERESTARTSYS:
	case -ERESTARTNOINTR:
	regs->d0 = regs->orig_d0;
	stepback(regs);
	break;

	case -ERESTART_RESTARTBLOCK:
	regs->d0 = __NR_restart_syscall;
	stepback(regs);
	break;
	}
	}

	/* if there's no signal to deliver, we just put the saved sigmask
	* back */
	restore_saved_sigmask();
	}

	/*
	* notification of userspace execution resumption
	* - triggered by current->work.notify_resume
	*/
	asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)
	{
	/* Pending single-step? */
	if (thread_info_flags & _TIF_SINGLESTEP) {
	#ifndef CONFIG_MN10300_USING_JTAG
	regs->epsw \|= EPSW_T;
	clear_thread_flag(TIF_SINGLESTEP);
	#else
	BUG(); /* no h/w single-step if using JTAG unit */
	#endif
	}

	/* deal with pending signal delivery */
	if (thread_info_flags & _TIF_SIGPENDING)
	do_signal(regs);

	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	clear_thread_flag(TIF_NOTIFY_RESUME);
	tracehook_notify_resume(current_frame());
	}
	}