[deliverable/linux.git] / arch / frv / kernel / signal.c

/* signal.c: FRV specific bits of signal handling
 *
 * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 * - Derived from arch/m68k/kernel/signal.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, 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/personality.h>
#include <linux/tracehook.h>
#include <asm/ucontext.h>
#include <asm/uaccess.h>
#include <asm/cacheflush.h>

#define DEBUG_SIG 0

struct fdpic_func_descriptor {
	unsigned long	text;
	unsigned long	GOT;
};

/*
 * Do a signal return; undo the signal stack.
 */

struct sigframe
{
	__sigrestore_t pretcode;
	int sig;
	struct sigcontext sc;
	unsigned long extramask[_NSIG_WORDS-1];
	uint32_t retcode[2];
};

struct rt_sigframe
{
	__sigrestore_t pretcode;
	int sig;
	struct siginfo __user *pinfo;
	void __user *puc;
	struct siginfo info;
	struct ucontext uc;
	uint32_t retcode[2];
};

static int restore_sigcontext(struct sigcontext __user *sc, int *_gr8)
{
	struct user_context *user = current->thread.user;
	unsigned long tbr, psr;

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

	tbr = user->i.tbr;
	psr = user->i.psr;
	if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))
		goto badframe;
	user->i.tbr = tbr;
	user->i.psr = psr;

	restore_user_regs(user);

	user->i.syscallno = -1;		/* disable syscall checks */

	*_gr8 = user->i.gr[8];
	return 0;

 badframe:
	return 1;
}

asmlinkage int sys_sigreturn(void)
{
	struct sigframe __user *frame = (struct sigframe __user *) __frame->sp;
	sigset_t set;
	int gr8;

	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
		goto badframe;
	if (__get_user(set.sig[0], &frame->sc.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(&frame->sc, &gr8))
		goto badframe;
	return gr8;

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

asmlinkage int sys_rt_sigreturn(void)
{
	struct rt_sigframe __user *frame = (struct rt_sigframe __user *) __frame->sp;
	sigset_t set;
	int gr8;

	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(&frame->uc.uc_mcontext, &gr8))
		goto badframe;

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

	return gr8;

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

/*
 * Set up a signal frame
 */
static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
{
	save_user_regs(current->thread.user);

	if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
		goto badframe;

	/* non-iBCS2 extensions.. */
	if (__put_user(mask, &sc->sc_oldmask) < 0)
		goto badframe;

	return 0;

 badframe:
	return 1;
}

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

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

} /* end get_sigframe() */

/*****************************************************************************/
/*
 *
 */
static int setup_frame(struct ksignal *ksig, sigset_t *set)
{
	struct sigframe __user *frame;
	int rsig, sig = ksig->sig;

	set_fs(USER_DS);

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

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

	rsig = sig;
	if (sig < 32 &&
	    __current_thread_info->exec_domain &&
	    __current_thread_info->exec_domain->signal_invmap)
		rsig = __current_thread_info->exec_domain->signal_invmap[sig];

	if (__put_user(rsig, &frame->sig) < 0)
		return -EFAULT;

	if (setup_sigcontext(&frame->sc, 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) < 0)
			return -EFAULT;
	}
	else {
		/* Set up the following code on the stack:
		 *	setlos	#__NR_sigreturn,gr7
		 *	tira	gr0,0
		 */
		if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
		    __put_user(0x8efc0000|__NR_sigreturn, &frame->retcode[0]) ||
		    __put_user(0xc0700000, &frame->retcode[1]))
			return -EFAULT;

		flush_icache_range((unsigned long) frame->retcode,
				   (unsigned long) (frame->retcode + 2));
	}

	/* Set up registers for the signal handler */
	if (current->personality & FDPIC_FUNCPTRS) {
		struct fdpic_func_descriptor __user *funcptr =
			(struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
		struct fdpic_func_descriptor desc;
		if (copy_from_user(&desc, funcptr, sizeof(desc)))
			return -EFAULT;
		__frame->pc = desc.text;
		__frame->gr15 = desc.GOT;
	} else {
		__frame->pc   = (unsigned long) ksig->ka.sa.sa_handler;
		__frame->gr15 = 0;
	}

	__frame->sp   = (unsigned long) frame;
	__frame->lr   = (unsigned long) &frame->retcode;
	__frame->gr8  = sig;

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

	return 0;
} /* end setup_frame() */

/*****************************************************************************/
/*
 *
 */
static int setup_rt_frame(struct ksignal *ksig, sigset_t *set)
{
	struct rt_sigframe __user *frame;
	int rsig, sig = ksig->sig;

	set_fs(USER_DS);

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

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

	rsig = sig;
	if (sig < 32 &&
	    __current_thread_info->exec_domain &&
	    __current_thread_info->exec_domain->signal_invmap)
		rsig = __current_thread_info->exec_domain->signal_invmap[sig];

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

	if (copy_siginfo_to_user(&frame->info, &ksig->info))
		return -EFAULT;

	/* Create the ucontext.  */
	if (__put_user(0, &frame->uc.uc_flags) ||
	    __put_user(NULL, &frame->uc.uc_link) ||
	    __save_altstack(&frame->uc.uc_stack, __frame->sp))
		return -EFAULT;

	if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
		return -EFAULT;

	if (__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 {
		/* Set up the following code on the stack:
		 *	setlos	#__NR_sigreturn,gr7
		 *	tira	gr0,0
		 */
		if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) ||
		    __put_user(0x8efc0000|__NR_rt_sigreturn, &frame->retcode[0]) ||
		    __put_user(0xc0700000, &frame->retcode[1]))
			return -EFAULT;

		flush_icache_range((unsigned long) frame->retcode,
				   (unsigned long) (frame->retcode + 2));
	}

	/* Set up registers for signal handler */
	if (current->personality & FDPIC_FUNCPTRS) {
		struct fdpic_func_descriptor __user *funcptr =
			(struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
		struct fdpic_func_descriptor desc;
		if (copy_from_user(&desc, funcptr, sizeof(desc)))
			return -EFAULT;
		__frame->pc = desc.text;
		__frame->gr15 = desc.GOT;
	} else {
		__frame->pc   = (unsigned long) ksig->ka.sa.sa_handler;
		__frame->gr15 = 0;
	}

	__frame->sp  = (unsigned long) frame;
	__frame->lr  = (unsigned long) &frame->retcode;
	__frame->gr8 = sig;
	__frame->gr9 = (unsigned long) &frame->info;

#if DEBUG_SIG
	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
	       sig, current->comm, current->pid, frame, __frame->pc,
	       frame->pretcode);
#endif
	return 0;

} /* end setup_rt_frame() */

/*****************************************************************************/
/*
 * OK, we're invoking a handler
 */
static void handle_signal(struct ksignal *ksig)
{
	sigset_t *oldset = sigmask_to_save();
	int ret;

	/* Are we from a system call? */
	if (__frame->syscallno != -1) {
		/* If so, check system call restarting.. */
		switch (__frame->gr8) {
		case -ERESTART_RESTARTBLOCK:
		case -ERESTARTNOHAND:
			__frame->gr8 = -EINTR;
			break;

		case -ERESTARTSYS:
			if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
				__frame->gr8 = -EINTR;
				break;
			}

			/* fallthrough */
		case -ERESTARTNOINTR:
			__frame->gr8 = __frame->orig_gr8;
			__frame->pc -= 4;
		}
		__frame->syscallno = -1;
	}

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

	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
} /* end handle_signal() */

/*****************************************************************************/
/*
 * 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.
 */
static void do_signal(void)
{
	struct ksignal ksig;

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

	/* Did we come from a system call? */
	if (__frame->syscallno != -1) {
		/* Restart the system call - no handlers present */
		switch (__frame->gr8) {
		case -ERESTARTNOHAND:
		case -ERESTARTSYS:
		case -ERESTARTNOINTR:
			__frame->gr8 = __frame->orig_gr8;
			__frame->pc -= 4;
			break;

		case -ERESTART_RESTARTBLOCK:
			__frame->gr7 = __NR_restart_syscall;
			__frame->pc -= 4;
			break;
		}
		__frame->syscallno = -1;
	}

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

/*****************************************************************************/
/*
 * notification of userspace execution resumption
 * - triggered by the TIF_WORK_MASK flags
 */
asmlinkage void do_notify_resume(__u32 thread_info_flags)
{
	/* pending single-step? */
	if (thread_info_flags & _TIF_SINGLESTEP)
		clear_thread_flag(TIF_SINGLESTEP);

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

	/* deal with notification on about to resume userspace execution */
	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
		clear_thread_flag(TIF_NOTIFY_RESUME);
		tracehook_notify_resume(__frame);
	}

} /* end do_notify_resume() */
Commit	Line	Data
1da177e4 LT	1	/* signal.c: FRV specific bits of signal handling
	2	*
	3	* Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	* - Derived from arch/m68k/kernel/signal.c
	6	*
	7	* This program is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License
	9	* as published by the Free Software Foundation; either version
	10	* 2 of the License, or (at your option) any later version.
	11	*/
	12
	13	#include <linux/sched.h>
	14	#include <linux/mm.h>
	15	#include <linux/smp.h>
1da177e4 LT	16	#include <linux/kernel.h>
	17	#include <linux/signal.h>
	18	#include <linux/errno.h>
	19	#include <linux/wait.h>
	20	#include <linux/ptrace.h>
	21	#include <linux/unistd.h>
	22	#include <linux/personality.h>
4a3b9893	23	#include <linux/tracehook.h>
1da177e4 LT	24	#include <asm/ucontext.h>
	25	#include <asm/uaccess.h>
	26	#include <asm/cacheflush.h>
	27
	28	#define DEBUG_SIG 0
	29
1da177e4 LT	30	struct fdpic_func_descriptor {
	31	unsigned long text;
	32	unsigned long GOT;
	33	};
	34
1da177e4 LT	35	/*
	36	* Do a signal return; undo the signal stack.
	37	*/
	38
	39	struct sigframe
	40	{
9e4d11f8	41	__sigrestore_t pretcode;
1da177e4 LT	42	int sig;
	43	struct sigcontext sc;
	44	unsigned long extramask[_NSIG_WORDS-1];
	45	uint32_t retcode[2];
	46	};
	47
	48	struct rt_sigframe
	49	{
9e4d11f8	50	__sigrestore_t pretcode;
1da177e4	51	int sig;
9e4d11f8 AV	52	struct siginfo __user *pinfo;
9e4d11f8 AV	53	void __user *puc;
1da177e4 LT	54	struct siginfo info;
	55	struct ucontext uc;
	56	uint32_t retcode[2];
	57	};
	58
	59	static int restore_sigcontext(struct sigcontext __user sc, int _gr8)
	60	{
	61	struct user_context *user = current->thread.user;
	62	unsigned long tbr, psr;
	63
20cd514d AV	64	/* Always make any pending restarted system calls return -EINTR */
	65	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	66
1da177e4 LT	67	tbr = user->i.tbr;
	68	psr = user->i.psr;
	69	if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))
	70	goto badframe;
	71	user->i.tbr = tbr;
	72	user->i.psr = psr;
	73
	74	restore_user_regs(user);
	75
	76	user->i.syscallno = -1; /* disable syscall checks */
	77
	78	*_gr8 = user->i.gr[8];
	79	return 0;
	80
	81	badframe:
	82	return 1;
	83	}
	84
	85	asmlinkage int sys_sigreturn(void)
	86	{
	87	struct sigframe __user frame = (struct sigframe __user ) __frame->sp;
	88	sigset_t set;
	89	int gr8;
	90
	91	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	92	goto badframe;
	93	if (__get_user(set.sig[0], &frame->sc.sc_oldmask))
	94	goto badframe;
	95
	96	if (_NSIG_WORDS > 1 &&
	97	__copy_from_user(&set.sig[1], &frame->extramask, sizeof(frame->extramask)))
	98	goto badframe;
	99
7ebe0c5d	100	set_current_blocked(&set);
1da177e4 LT	101
	102	if (restore_sigcontext(&frame->sc, &gr8))
	103	goto badframe;
	104	return gr8;
	105
	106	badframe:
	107	force_sig(SIGSEGV, current);
	108	return 0;
	109	}
	110
	111	asmlinkage int sys_rt_sigreturn(void)
	112	{
	113	struct rt_sigframe __user frame = (struct rt_sigframe __user ) __frame->sp;
	114	sigset_t set;
	115	int gr8;
	116
	117	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	118	goto badframe;
	119	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
	120	goto badframe;
	121
7ebe0c5d	122	set_current_blocked(&set);
1da177e4 LT	123
	124	if (restore_sigcontext(&frame->uc.uc_mcontext, &gr8))
	125	goto badframe;
	126
fe761416	127	if (restore_altstack(&frame->uc.uc_stack))
1da177e4 LT	128	goto badframe;
	129
	130	return gr8;
	131
	132	badframe:
	133	force_sig(SIGSEGV, current);
	134	return 0;
	135	}
	136
	137	/*
	138	* Set up a signal frame
	139	*/
	140	static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
	141	{
	142	save_user_regs(current->thread.user);
	143
	144	if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
	145	goto badframe;
	146
	147	/* non-iBCS2 extensions.. */
	148	if (__put_user(mask, &sc->sc_oldmask) < 0)
	149	goto badframe;
	150
	151	return 0;
	152
	153	badframe:
	154	return 1;
	155	}
	156
	157	/*****************************************************************************/
	158	/*
	159	* Determine which stack to use..
	160	*/
4a03ac36	161	static inline void __user get_sigframe(struct ksignal ksig,
1da177e4 LT	162	size_t frame_size)
1da177e4 LT	163	{
4a03ac36	164	unsigned long sp = sigsp(__frame->sp, ksig);
1da177e4 LT	165
1da177e4 LT	166	return (void __user *) ((sp - frame_size) & ~7UL);
fef2b580	167
1da177e4 LT	168	} /* end get_sigframe() */
	169
	170	/*****************************************************************************/
	171	/*
	172	*
	173	*/
720f36b9	174	static int setup_frame(struct ksignal ksig, sigset_t set)
1da177e4 LT	175	{
1da177e4 LT	176	struct sigframe __user *frame;
720f36b9	177	int rsig, sig = ksig->sig;
1da177e4	178
5f4ad04a AV	179	set_fs(USER_DS);
5f4ad04a AV	180
4a03ac36	181	frame = get_sigframe(ksig, sizeof(*frame));
1da177e4 LT	182
1da177e4 LT	183	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
720f36b9	184	return -EFAULT;
1da177e4 LT	185
	186	rsig = sig;
	187	if (sig < 32 &&
	188	__current_thread_info->exec_domain &&
	189	__current_thread_info->exec_domain->signal_invmap)
	190	rsig = __current_thread_info->exec_domain->signal_invmap[sig];
	191
	192	if (__put_user(rsig, &frame->sig) < 0)
720f36b9	193	return -EFAULT;
1da177e4 LT	194
1da177e4 LT	195	if (setup_sigcontext(&frame->sc, set->sig[0]))
720f36b9	196	return -EFAULT;
1da177e4 LT	197
	198	if (_NSIG_WORDS > 1) {
	199	if (__copy_to_user(frame->extramask, &set->sig[1],
	200	sizeof(frame->extramask)))
720f36b9	201	return -EFAULT;
1da177e4 LT	202	}
	203
	204	/* Set up to return from userspace. If provided, use a stub
	205	* already in userspace. */
720f36b9 RW	206	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
	207	if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode) < 0)
	208	return -EFAULT;
1da177e4 LT	209	}
	210	else {
	211	/* Set up the following code on the stack:
	212	* setlos #__NR_sigreturn,gr7
	213	* tira gr0,0
	214	*/
9e4d11f8	215	if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) \|\|
1da177e4 LT	216	__put_user(0x8efc0000\|__NR_sigreturn, &frame->retcode[0]) \|\|
1da177e4 LT	217	__put_user(0xc0700000, &frame->retcode[1]))
720f36b9	218	return -EFAULT;
1da177e4 LT	219
	220	flush_icache_range((unsigned long) frame->retcode,
	221	(unsigned long) (frame->retcode + 2));
	222	}
	223
5f4ad04a	224	/* Set up registers for the signal handler */
ecd0fa98	225	if (current->personality & FDPIC_FUNCPTRS) {
1da177e4	226	struct fdpic_func_descriptor __user *funcptr =
720f36b9	227	(struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
5f4ad04a AV	228	struct fdpic_func_descriptor desc;
5f4ad04a AV	229	if (copy_from_user(&desc, funcptr, sizeof(desc)))
720f36b9	230	return -EFAULT;
5f4ad04a AV	231	__frame->pc = desc.text;
5f4ad04a AV	232	__frame->gr15 = desc.GOT;
1da177e4	233	} else {
720f36b9	234	__frame->pc = (unsigned long) ksig->ka.sa.sa_handler;
fef2b580	235	__frame->gr15 = 0;
1da177e4 LT	236	}
1da177e4 LT	237
5f4ad04a AV	238	__frame->sp = (unsigned long) frame;
	239	__frame->lr = (unsigned long) &frame->retcode;
	240	__frame->gr8 = sig;
1da177e4 LT	241
	242	#if DEBUG_SIG
	243	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
fef2b580	244	sig, current->comm, current->pid, frame, __frame->pc,
8efc0ab5	245	frame->pretcode);
1da177e4 LT	246	#endif
1da177e4 LT	247
a411aee9	248	return 0;
1da177e4 LT	249	} /* end setup_frame() */
	250
	251	/*****************************************************************************/
	252	/*
	253	*
	254	*/
720f36b9	255	static int setup_rt_frame(struct ksignal ksig, sigset_t set)
1da177e4 LT	256	{
1da177e4 LT	257	struct rt_sigframe __user *frame;
720f36b9	258	int rsig, sig = ksig->sig;
1da177e4	259
5f4ad04a AV	260	set_fs(USER_DS);
5f4ad04a AV	261
4a03ac36	262	frame = get_sigframe(ksig, sizeof(*frame));
1da177e4 LT	263
1da177e4 LT	264	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
720f36b9	265	return -EFAULT;
1da177e4 LT	266
	267	rsig = sig;
	268	if (sig < 32 &&
	269	__current_thread_info->exec_domain &&
	270	__current_thread_info->exec_domain->signal_invmap)
	271	rsig = __current_thread_info->exec_domain->signal_invmap[sig];
	272
	273	if (__put_user(rsig, &frame->sig) \|\|
	274	__put_user(&frame->info, &frame->pinfo) \|\|
	275	__put_user(&frame->uc, &frame->puc))
720f36b9	276	return -EFAULT;
1da177e4	277
720f36b9 RW	278	if (copy_siginfo_to_user(&frame->info, &ksig->info))
720f36b9 RW	279	return -EFAULT;
1da177e4 LT	280
	281	/* Create the ucontext. */
	282	if (__put_user(0, &frame->uc.uc_flags) \|\|
9e4d11f8	283	__put_user(NULL, &frame->uc.uc_link) \|\|
fe761416	284	__save_altstack(&frame->uc.uc_stack, __frame->sp))
720f36b9	285	return -EFAULT;
1da177e4 LT	286
1da177e4 LT	287	if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
720f36b9	288	return -EFAULT;
1da177e4 LT	289
1da177e4 LT	290	if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
720f36b9	291	return -EFAULT;
1da177e4 LT	292
	293	/* Set up to return from userspace. If provided, use a stub
	294	* already in userspace. */
720f36b9 RW	295	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
	296	if (__put_user(ksig->ka.sa.sa_restorer, &frame->pretcode))
	297	return -EFAULT;
1da177e4 LT	298	}
	299	else {
	300	/* Set up the following code on the stack:
	301	* setlos #__NR_sigreturn,gr7
	302	* tira gr0,0
	303	*/
9e4d11f8	304	if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) \|\|
1da177e4 LT	305	__put_user(0x8efc0000\|__NR_rt_sigreturn, &frame->retcode[0]) \|\|
1da177e4 LT	306	__put_user(0xc0700000, &frame->retcode[1]))
720f36b9	307	return -EFAULT;
1da177e4 LT	308
	309	flush_icache_range((unsigned long) frame->retcode,
	310	(unsigned long) (frame->retcode + 2));
	311	}
	312
	313	/* Set up registers for signal handler */
ecd0fa98	314	if (current->personality & FDPIC_FUNCPTRS) {
9e4d11f8	315	struct fdpic_func_descriptor __user *funcptr =
720f36b9	316	(struct fdpic_func_descriptor __user *) ksig->ka.sa.sa_handler;
5f4ad04a AV	317	struct fdpic_func_descriptor desc;
5f4ad04a AV	318	if (copy_from_user(&desc, funcptr, sizeof(desc)))
720f36b9	319	return -EFAULT;
5f4ad04a AV	320	__frame->pc = desc.text;
5f4ad04a AV	321	__frame->gr15 = desc.GOT;
1da177e4	322	} else {
720f36b9	323	__frame->pc = (unsigned long) ksig->ka.sa.sa_handler;
fef2b580	324	__frame->gr15 = 0;
1da177e4 LT	325	}
1da177e4 LT	326
5f4ad04a AV	327	__frame->sp = (unsigned long) frame;
	328	__frame->lr = (unsigned long) &frame->retcode;
	329	__frame->gr8 = sig;
	330	__frame->gr9 = (unsigned long) &frame->info;
1da177e4 LT	331
	332	#if DEBUG_SIG
	333	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
fef2b580	334	sig, current->comm, current->pid, frame, __frame->pc,
8efc0ab5	335	frame->pretcode);
1da177e4	336	#endif
a411aee9	337	return 0;
1da177e4	338
1da177e4 LT	339	} /* end setup_rt_frame() */
	340
	341	/*****************************************************************************/
	342	/*
	343	* OK, we're invoking a handler
	344	*/
720f36b9	345	static void handle_signal(struct ksignal *ksig)
1da177e4	346	{
b7f9a11a	347	sigset_t *oldset = sigmask_to_save();
8efc0ab5 DH	348	int ret;
8efc0ab5 DH	349
1da177e4	350	/* Are we from a system call? */
ed1cde68	351	if (__frame->syscallno != -1) {
1da177e4	352	/* If so, check system call restarting.. */
fef2b580	353	switch (__frame->gr8) {
1da177e4 LT	354	case -ERESTART_RESTARTBLOCK:
1da177e4 LT	355	case -ERESTARTNOHAND:
fef2b580	356	__frame->gr8 = -EINTR;
1da177e4 LT	357	break;
	358
	359	case -ERESTARTSYS:
720f36b9	360	if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
fef2b580	361	__frame->gr8 = -EINTR;
1da177e4 LT	362	break;
1da177e4 LT	363	}
8efc0ab5	364
1da177e4 LT	365	/* fallthrough */
1da177e4 LT	366	case -ERESTARTNOINTR:
fef2b580 DH	367	__frame->gr8 = __frame->orig_gr8;
fef2b580 DH	368	__frame->pc -= 4;
1da177e4	369	}
ed1cde68	370	__frame->syscallno = -1;
1da177e4 LT	371	}
	372
	373	/* Set up the stack frame */
720f36b9 RW	374	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
720f36b9 RW	375	ret = setup_rt_frame(ksig, oldset);
1da177e4	376	else
720f36b9	377	ret = setup_frame(ksig, oldset);
1da177e4	378
720f36b9	379	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
1da177e4 LT	380	} /* end handle_signal() */
	381
	382	/*****************************************************************************/
	383	/*
	384	* Note that 'init' is a special process: it doesn't get signals it doesn't
	385	* want to handle. Thus you cannot kill init even with a SIGKILL even by
	386	* mistake.
	387	*/
a411aee9	388	static void do_signal(void)
1da177e4	389	{
720f36b9	390	struct ksignal ksig;
1da177e4	391
720f36b9 RW	392	if (get_signal(&ksig)) {
720f36b9 RW	393	handle_signal(&ksig);
a411aee9 DH	394	return;
a411aee9 DH	395	}
1da177e4	396
1da177e4	397	/* Did we come from a system call? */
c896a2e0	398	if (__frame->syscallno != -1) {
1da177e4	399	/* Restart the system call - no handlers present */
a411aee9 DH	400	switch (__frame->gr8) {
	401	case -ERESTARTNOHAND:
	402	case -ERESTARTSYS:
	403	case -ERESTARTNOINTR:
fef2b580 DH	404	__frame->gr8 = __frame->orig_gr8;
fef2b580 DH	405	__frame->pc -= 4;
a411aee9	406	break;
1da177e4	407
a411aee9	408	case -ERESTART_RESTARTBLOCK:
44c7afff	409	__frame->gr7 = __NR_restart_syscall;
fef2b580	410	__frame->pc -= 4;
a411aee9	411	break;
1da177e4	412	}
ed1cde68	413	__frame->syscallno = -1;
1da177e4 LT	414	}
1da177e4 LT	415
a411aee9 DH	416	/* if there's no signal to deliver, we just put the saved sigmask
a411aee9 DH	417	* back */
51a7b448	418	restore_saved_sigmask();
1da177e4 LT	419	} /* end do_signal() */
	420
	421	/*****************************************************************************/
	422	/*
	423	* notification of userspace execution resumption
a411aee9	424	* - triggered by the TIF_WORK_MASK flags
1da177e4 LT	425	*/
	426	asmlinkage void do_notify_resume(__u32 thread_info_flags)
	427	{
	428	/* pending single-step? */
	429	if (thread_info_flags & _TIF_SINGLESTEP)
	430	clear_thread_flag(TIF_SINGLESTEP);
	431
	432	/* deal with pending signal delivery */
a3936249	433	if (thread_info_flags & _TIF_SIGPENDING)
a411aee9	434	do_signal();
1da177e4	435
b7bab880 DH	436	/* deal with notification on about to resume userspace execution */
	437	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	438	clear_thread_flag(TIF_NOTIFY_RESUME);
4a3b9893	439	tracehook_notify_resume(__frame);
b7bab880 DH	440	}
b7bab880 DH	441
1da177e4	442	} /* end do_notify_resume() */