[mirror_ubuntu-artful-kernel.git] / arch / mn10300 / kernel / signal.c

/* 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 <linux/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 (!access_ok(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 (!access_ok(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 (!access_ok(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());
	}
}
Commit	Line	Data
b920de1b DH	1	/* MN10300 Signal handling
	2	*
	3	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public Licence
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the Licence, or (at your option) any later version.
	10	*/
	11
	12	#include <linux/sched.h>
	13	#include <linux/mm.h>
	14	#include <linux/smp.h>
b920de1b DH	15	#include <linux/kernel.h>
	16	#include <linux/signal.h>
	17	#include <linux/errno.h>
	18	#include <linux/wait.h>
	19	#include <linux/ptrace.h>
	20	#include <linux/unistd.h>
	21	#include <linux/stddef.h>
	22	#include <linux/tty.h>
	23	#include <linux/personality.h>
	24	#include <linux/suspend.h>
5d289964	25	#include <linux/tracehook.h>
b920de1b DH	26	#include <asm/cacheflush.h>
b920de1b DH	27	#include <asm/ucontext.h>
7c0f6ba6	28	#include <linux/uaccess.h>
b920de1b DH	29	#include <asm/fpu.h>
	30	#include "sigframe.h"
	31
	32	#define DEBUG_SIG 0
	33
b920de1b DH	34	/*
	35	* do a signal return; undo the signal stack.
	36	*/
	37	static int restore_sigcontext(struct pt_regs *regs,
	38	struct sigcontext __user sc, long _d0)
	39	{
	40	unsigned int err = 0;
	41
c05628b4	42	/* Always make any pending restarted system calls return -EINTR */
f56141e3	43	current->restart_block.fn = do_no_restart_syscall;
c05628b4	44
b920de1b DH	45	if (is_using_fpu(current))
	46	fpu_kill_state(current);
	47
	48	#define COPY(x) err \|= __get_user(regs->x, &sc->x)
	49	COPY(d1); COPY(d2); COPY(d3);
	50	COPY(a0); COPY(a1); COPY(a2); COPY(a3);
	51	COPY(e0); COPY(e1); COPY(e2); COPY(e3);
	52	COPY(e4); COPY(e5); COPY(e6); COPY(e7);
	53	COPY(lar); COPY(lir);
	54	COPY(mdr); COPY(mdrq);
	55	COPY(mcvf); COPY(mcrl); COPY(mcrh);
	56	COPY(sp); COPY(pc);
	57	#undef COPY
	58
	59	{
	60	unsigned int tmpflags;
	61	#ifndef CONFIG_MN10300_USING_JTAG
	62	#define USER_EPSW (EPSW_FLAG_Z \| EPSW_FLAG_N \| EPSW_FLAG_C \| EPSW_FLAG_V \| \
	63	EPSW_T \| EPSW_nAR)
	64	#else
	65	#define USER_EPSW (EPSW_FLAG_Z \| EPSW_FLAG_N \| EPSW_FLAG_C \| EPSW_FLAG_V \| \
	66	EPSW_nAR)
	67	#endif
	68	err \|= __get_user(tmpflags, &sc->epsw);
	69	regs->epsw = (regs->epsw & ~USER_EPSW) \|
	70	(tmpflags & USER_EPSW);
	71	regs->orig_d0 = -1; /* disable syscall checks */
	72	}
	73
	74	{
	75	struct fpucontext *buf;
	76	err \|= __get_user(buf, &sc->fpucontext);
	77	if (buf) {
81029b1f	78	if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
b920de1b DH	79	goto badframe;
	80	err \|= fpu_restore_sigcontext(buf);
	81	}
	82	}
	83
	84	err \|= __get_user(*_d0, &sc->d0);
	85	return err;
	86
	87	badframe:
	88	return 1;
	89	}
	90
	91	/*
	92	* standard signal return syscall
	93	*/
	94	asmlinkage long sys_sigreturn(void)
	95	{
7c7fcf76	96	struct sigframe __user *frame;
b920de1b DH	97	sigset_t set;
	98	long d0;
	99
7c7fcf76	100	frame = (struct sigframe __user *) current_frame()->sp;
81029b1f	101	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
b920de1b DH	102	goto badframe;
	103	if (__get_user(set.sig[0], &frame->sc.oldmask))
	104	goto badframe;
	105
	106	if (_NSIG_WORDS > 1 &&
	107	__copy_from_user(&set.sig[1], &frame->extramask,
	108	sizeof(frame->extramask)))
	109	goto badframe;
	110
00f35785	111	set_current_blocked(&set);
b920de1b	112
7c7fcf76	113	if (restore_sigcontext(current_frame(), &frame->sc, &d0))
b920de1b DH	114	goto badframe;
	115
	116	return d0;
	117
	118	badframe:
	119	force_sig(SIGSEGV, current);
	120	return 0;
	121	}
	122
	123	/*
	124	* realtime signal return syscall
	125	*/
	126	asmlinkage long sys_rt_sigreturn(void)
	127	{
7c7fcf76	128	struct rt_sigframe __user *frame;
b920de1b	129	sigset_t set;
7c7fcf76	130	long d0;
b920de1b	131
7c7fcf76	132	frame = (struct rt_sigframe __user *) current_frame()->sp;
81029b1f	133	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
b920de1b DH	134	goto badframe;
	135	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
	136	goto badframe;
	137
00f35785	138	set_current_blocked(&set);
b920de1b	139
7c7fcf76	140	if (restore_sigcontext(current_frame(), &frame->uc.uc_mcontext, &d0))
b920de1b DH	141	goto badframe;
b920de1b DH	142
b30c7d50	143	if (restore_altstack(&frame->uc.uc_stack))
b920de1b DH	144	goto badframe;
	145
	146	return d0;
	147
	148	badframe:
	149	force_sig(SIGSEGV, current);
	150	return 0;
	151	}
	152
	153	/*
	154	* store the userspace context into a signal frame
	155	*/
	156	static int setup_sigcontext(struct sigcontext __user *sc,
	157	struct fpucontext *fpuctx,
	158	struct pt_regs *regs,
	159	unsigned long mask)
	160	{
	161	int tmp, err = 0;
	162
	163	#define COPY(x) err \|= __put_user(regs->x, &sc->x)
	164	COPY(d0); COPY(d1); COPY(d2); COPY(d3);
	165	COPY(a0); COPY(a1); COPY(a2); COPY(a3);
	166	COPY(e0); COPY(e1); COPY(e2); COPY(e3);
	167	COPY(e4); COPY(e5); COPY(e6); COPY(e7);
	168	COPY(lar); COPY(lir);
	169	COPY(mdr); COPY(mdrq);
	170	COPY(mcvf); COPY(mcrl); COPY(mcrh);
	171	COPY(sp); COPY(epsw); COPY(pc);
	172	#undef COPY
	173
	174	tmp = fpu_setup_sigcontext(fpuctx);
	175	if (tmp < 0)
	176	err = 1;
	177	else
	178	err \|= __put_user(tmp ? fpuctx : NULL, &sc->fpucontext);
	179
	180	/* non-iBCS2 extensions.. */
	181	err \|= __put_user(mask, &sc->oldmask);
	182
	183	return err;
	184	}
	185
	186	/*
	187	* determine which stack to use..
	188	*/
a8040ff8	189	static inline void __user get_sigframe(struct ksignal ksig,
b920de1b DH	190	struct pt_regs *regs,
	191	size_t frame_size)
	192	{
a8040ff8	193	unsigned long sp = sigsp(regs->sp, ksig);
b920de1b DH	194
	195	return (void __user *) ((sp - frame_size) & ~7UL);
	196	}
	197
	198	/*
	199	* set up a normal signal frame
	200	*/
8b166553	201	static int setup_frame(struct ksignal ksig, sigset_t set,
b920de1b DH	202	struct pt_regs *regs)
	203	{
	204	struct sigframe __user *frame;
78d156b8	205	int sig = ksig->sig;
b920de1b	206
a8040ff8	207	frame = get_sigframe(ksig, regs, sizeof(*frame));
b920de1b DH	208
b920de1b DH	209	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
8b166553	210	return -EFAULT;
b920de1b	211
78d156b8	212	if (__put_user(sig, &frame->sig) < 0 \|\|
b920de1b	213	__put_user(&frame->sc, &frame->psc) < 0)
8b166553	214	return -EFAULT;
b920de1b DH	215
b920de1b DH	216	if (setup_sigcontext(&frame->sc, &frame->fpuctx, regs, set->sig[0]))
8b166553	217	return -EFAULT;
b920de1b DH	218
	219	if (_NSIG_WORDS > 1) {
	220	if (__copy_to_user(frame->extramask, &set->sig[1],
	221	sizeof(frame->extramask)))
8b166553	222	return -EFAULT;
b920de1b DH	223	}
	224
	225	/* set up to return from userspace. If provided, use a stub already in
	226	* userspace */
8b166553 RW	227	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
	228	if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
	229	return -EFAULT;
b920de1b DH	230	} else {
	231	if (__put_user((void (*)(void))frame->retcode,
	232	&frame->pretcode))
8b166553	233	return -EFAULT;
b920de1b DH	234	/* this is mov $,d0; syscall 0 */
	235	if (__put_user(0x2c, (char *)(frame->retcode + 0)) \|\|
	236	__put_user(__NR_sigreturn, (char *)(frame->retcode + 1)) \|\|
	237	__put_user(0x00, (char *)(frame->retcode + 2)) \|\|
	238	__put_user(0xf0, (char *)(frame->retcode + 3)) \|\|
	239	__put_user(0xe0, (char *)(frame->retcode + 4)))
8b166553	240	return -EFAULT;
b920de1b DH	241	flush_icache_range((unsigned long) frame->retcode,
	242	(unsigned long) frame->retcode + 5);
	243	}
	244
	245	/* set up registers for signal handler */
	246	regs->sp = (unsigned long) frame;
8b166553	247	regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
b920de1b DH	248	regs->d0 = sig;
	249	regs->d1 = (unsigned long) &frame->sc;
	250
b920de1b DH	251	#if DEBUG_SIG
	252	printk(KERN_DEBUG "SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
	253	sig, current->comm, current->pid, frame, regs->pc,
	254	frame->pretcode);
	255	#endif
	256
	257	return 0;
b920de1b DH	258	}
	259
	260	/*
	261	* set up a realtime signal frame
	262	*/
8b166553 RW	263	static int setup_rt_frame(struct ksignal ksig, sigset_t set,
8b166553 RW	264	struct pt_regs *regs)
b920de1b DH	265	{
b920de1b DH	266	struct rt_sigframe __user *frame;
78d156b8	267	int sig = ksig->sig;
b920de1b	268
a8040ff8	269	frame = get_sigframe(ksig, regs, sizeof(*frame));
b920de1b DH	270
b920de1b DH	271	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
8b166553	272	return -EFAULT;
b920de1b	273
78d156b8	274	if (__put_user(sig, &frame->sig) \|\|
b920de1b DH	275	__put_user(&frame->info, &frame->pinfo) \|\|
b920de1b DH	276	__put_user(&frame->uc, &frame->puc) \|\|
8b166553 RW	277	copy_siginfo_to_user(&frame->info, &ksig->info))
8b166553 RW	278	return -EFAULT;
b920de1b DH	279
	280	/* create the ucontext. */
	281	if (__put_user(0, &frame->uc.uc_flags) \|\|
	282	__put_user(0, &frame->uc.uc_link) \|\|
b30c7d50	283	__save_altstack(&frame->uc.uc_stack, regs->sp) \|\|
b920de1b DH	284	setup_sigcontext(&frame->uc.uc_mcontext,
	285	&frame->fpuctx, regs, set->sig[0]) \|\|
	286	__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
8b166553	287	return -EFAULT;
b920de1b DH	288
	289	/* set up to return from userspace. If provided, use a stub already in
	290	* userspace */
8b166553 RW	291	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
	292	if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
	293	return -EFAULT;
	294
b920de1b DH	295	} else {
	296	if (__put_user((void(*)(void))frame->retcode,
	297	&frame->pretcode) \|\|
	298	/* This is mov $,d0; syscall 0 */
	299	__put_user(0x2c, (char *)(frame->retcode + 0)) \|\|
	300	__put_user(__NR_rt_sigreturn,
	301	(char *)(frame->retcode + 1)) \|\|
	302	__put_user(0x00, (char *)(frame->retcode + 2)) \|\|
	303	__put_user(0xf0, (char *)(frame->retcode + 3)) \|\|
	304	__put_user(0xe0, (char *)(frame->retcode + 4)))
8b166553	305	return -EFAULT;
b920de1b DH	306
	307	flush_icache_range((u_long) frame->retcode,
	308	(u_long) frame->retcode + 5);
	309	}
	310
	311	/* Set up registers for signal handler */
	312	regs->sp = (unsigned long) frame;
8b166553	313	regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
b920de1b DH	314	regs->d0 = sig;
	315	regs->d1 = (long) &frame->info;
	316
b920de1b DH	317	#if DEBUG_SIG
	318	printk(KERN_DEBUG "SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
	319	sig, current->comm, current->pid, frame, regs->pc,
	320	frame->pretcode);
	321	#endif
	322
	323	return 0;
b920de1b DH	324	}
b920de1b DH	325
00cbf608 AV	326	static inline void stepback(struct pt_regs *regs)
	327	{
	328	regs->pc -= 2;
	329	regs->orig_d0 = -1;
	330	}
	331
b920de1b DH	332	/*
	333	* handle the actual delivery of a signal to userspace
	334	*/
8b166553	335	static int handle_signal(struct ksignal ksig, struct pt_regs regs)
b920de1b	336	{
b7f9a11a	337	sigset_t *oldset = sigmask_to_save();
b920de1b DH	338	int ret;
	339
	340	/* Are we from a system call? */
	341	if (regs->orig_d0 >= 0) {
	342	/* If so, check system call restarting.. */
	343	switch (regs->d0) {
	344	case -ERESTART_RESTARTBLOCK:
	345	case -ERESTARTNOHAND:
	346	regs->d0 = -EINTR;
	347	break;
	348
	349	case -ERESTARTSYS:
8b166553	350	if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
b920de1b DH	351	regs->d0 = -EINTR;
	352	break;
	353	}
	354
	355	/* fallthrough */
	356	case -ERESTARTNOINTR:
	357	regs->d0 = regs->orig_d0;
00cbf608	358	stepback(regs);
b920de1b DH	359	}
	360	}
	361
	362	/* Set up the stack frame */
8b166553 RW	363	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
8b166553 RW	364	ret = setup_rt_frame(ksig, oldset, regs);
b920de1b	365	else
8b166553	366	ret = setup_frame(ksig, oldset, regs);
b920de1b	367
8b166553	368	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
b45f9330	369	return 0;
b920de1b DH	370	}
	371
	372	/*
	373	* handle a potential signal
	374	*/
	375	static void do_signal(struct pt_regs *regs)
	376	{
8b166553	377	struct ksignal ksig;
b920de1b	378
8b166553 RW	379	if (get_signal(&ksig)) {
8b166553 RW	380	handle_signal(&ksig, regs);
b920de1b DH	381	return;
	382	}
	383
	384	/* did we come from a system call? */
	385	if (regs->orig_d0 >= 0) {
	386	/* restart the system call - no handlers present */
	387	switch (regs->d0) {
	388	case -ERESTARTNOHAND:
	389	case -ERESTARTSYS:
	390	case -ERESTARTNOINTR:
	391	regs->d0 = regs->orig_d0;
00cbf608	392	stepback(regs);
b920de1b DH	393	break;
	394
	395	case -ERESTART_RESTARTBLOCK:
	396	regs->d0 = __NR_restart_syscall;
00cbf608	397	stepback(regs);
b920de1b DH	398	break;
	399	}
	400	}
	401
	402	/* if there's no signal to deliver, we just put the saved sigmask
	403	* back */
51a7b448	404	restore_saved_sigmask();
b920de1b DH	405	}
	406
	407	/*
	408	* notification of userspace execution resumption
	409	* - triggered by current->work.notify_resume
	410	*/
	411	asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)
	412	{
	413	/* Pending single-step? */
	414	if (thread_info_flags & _TIF_SINGLESTEP) {
	415	#ifndef CONFIG_MN10300_USING_JTAG
	416	regs->epsw \|= EPSW_T;
	417	clear_thread_flag(TIF_SINGLESTEP);
	418	#else
	419	BUG(); /* no h/w single-step if using JTAG unit */
	420	#endif
	421	}
	422
	423	/* deal with pending signal delivery */
6fd84c08	424	if (thread_info_flags & _TIF_SIGPENDING)
b920de1b	425	do_signal(regs);
5d289964 DH	426
	427	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	428	clear_thread_flag(TIF_NOTIFY_RESUME);
7c7fcf76	429	tracehook_notify_resume(current_frame());
5d289964	430	}
b920de1b	431	}