[net-next-2.6.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/smp_lock.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/freezer.h>
#include <asm/ucontext.h>
#include <asm/uaccess.h>
#include <asm/cacheflush.h>

#define DEBUG_SIG 0

#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

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

/*
 * Atomically swap in the new signal mask, and wait for a signal.
 */
asmlinkage int sys_sigsuspend(int history0, int history1, old_sigset_t mask)
{
	mask &= _BLOCKABLE;
	spin_lock_irq(&current->sighand->siglock);
	current->saved_sigmask = current->blocked;
	siginitset(&current->blocked, mask);
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	current->state = TASK_INTERRUPTIBLE;
	schedule();
	set_thread_flag(TIF_RESTORE_SIGMASK);
	return -ERESTARTNOHAND;
}

asmlinkage int sys_sigaction(int sig,
			     const struct old_sigaction __user *act,
			     struct old_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_restorer, &act->sa_restorer))
			return -EFAULT;
		__get_user(new_ka.sa.sa_flags, &act->sa_flags);
		__get_user(mask, &act->sa_mask);
		siginitset(&new_ka.sa.sa_mask, mask);
	}

	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_restorer, &oact->sa_restorer))
			return -EFAULT;
		__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
		__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
	}

	return ret;
}

asmlinkage
int sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
{
	return do_sigaltstack(uss, uoss, __frame->sp);
}


/*
 * 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;

	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;

	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	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;

	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, &gr8))
		goto badframe;

	if (do_sigaltstack(&frame->uc.uc_stack, NULL, __frame->sp) == -EFAULT)
		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 k_sigaction *ka,
					size_t frame_size)
{
	unsigned long sp;

	/* Default to using normal stack */
	sp = __frame->sp;

	/* This is the X/Open sanctioned signal stack switching.  */
	if (ka->sa.sa_flags & SA_ONSTACK) {
		if (! sas_ss_flags(sp))
			sp = current->sas_ss_sp + current->sas_ss_size;
	}

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

} /* end get_sigframe() */

/*****************************************************************************/
/*
 *
 */
static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set)
{
	struct sigframe __user *frame;
	int rsig;

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

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto give_sigsegv;

	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)
		goto give_sigsegv;

	if (setup_sigcontext(&frame->sc, set->sig[0]))
		goto give_sigsegv;

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

	/* Set up to return from userspace.  If provided, use a stub
	 * already in userspace.  */
	if (ka->sa.sa_flags & SA_RESTORER) {
		if (__put_user(ka->sa.sa_restorer, &frame->pretcode) < 0)
			goto give_sigsegv;
	}
	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]))
			goto give_sigsegv;

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

	/* set up registers for signal handler */
	__frame->sp   = (unsigned long) frame;
	__frame->lr   = (unsigned long) &frame->retcode;
	__frame->gr8  = sig;

	if (get_personality & FDPIC_FUNCPTRS) {
		struct fdpic_func_descriptor __user *funcptr =
			(struct fdpic_func_descriptor __user *) ka->sa.sa_handler;
		__get_user(__frame->pc, &funcptr->text);
		__get_user(__frame->gr15, &funcptr->GOT);
	} else {
		__frame->pc   = (unsigned long) ka->sa.sa_handler;
		__frame->gr15 = 0;
	}

	set_fs(USER_DS);

	/* the tracer may want to single-step inside the handler */
	if (test_thread_flag(TIF_SINGLESTEP))
		ptrace_notify(SIGTRAP);

#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;

give_sigsegv:
	force_sig(SIGSEGV, current);
	return -EFAULT;

} /* end setup_frame() */

/*****************************************************************************/
/*
 *
 */
static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
			  sigset_t *set)
{
	struct rt_sigframe __user *frame;
	int rsig;

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

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto give_sigsegv;

	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))
		goto give_sigsegv;

	if (copy_siginfo_to_user(&frame->info, info))
		goto give_sigsegv;

	/* Create the ucontext.  */
	if (__put_user(0, &frame->uc.uc_flags) ||
	    __put_user(NULL, &frame->uc.uc_link) ||
	    __put_user((void __user *)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp) ||
	    __put_user(sas_ss_flags(__frame->sp), &frame->uc.uc_stack.ss_flags) ||
	    __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size))
		goto give_sigsegv;

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

	if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
		goto give_sigsegv;

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

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

	/* Set up registers for signal handler */
	__frame->sp  = (unsigned long) frame;
	__frame->lr   = (unsigned long) &frame->retcode;
	__frame->gr8 = sig;
	__frame->gr9 = (unsigned long) &frame->info;

	if (get_personality & FDPIC_FUNCPTRS) {
		struct fdpic_func_descriptor __user *funcptr =
			(struct fdpic_func_descriptor __user *) ka->sa.sa_handler;
		__get_user(__frame->pc, &funcptr->text);
		__get_user(__frame->gr15, &funcptr->GOT);
	} else {
		__frame->pc   = (unsigned long) ka->sa.sa_handler;
		__frame->gr15 = 0;
	}

	set_fs(USER_DS);

	/* the tracer may want to single-step inside the handler */
	if (test_thread_flag(TIF_SINGLESTEP))
		ptrace_notify(SIGTRAP);

#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;

give_sigsegv:
	force_sig(SIGSEGV, current);
	return -EFAULT;

} /* end setup_rt_frame() */

/*****************************************************************************/
/*
 * OK, we're invoking a handler
 */
static int handle_signal(unsigned long sig, siginfo_t *info,
			 struct k_sigaction *ka, sigset_t *oldset)
{
	int ret;

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

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

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

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

	if (ret == 0) {
		spin_lock_irq(&current->sighand->siglock);
		sigorsets(&current->blocked, &current->blocked,
			  &ka->sa.sa_mask);
		if (!(ka->sa.sa_flags & SA_NODEFER))
			sigaddset(&current->blocked, sig);
		recalc_sigpending();
		spin_unlock_irq(&current->sighand->siglock);
	}

	return ret;

} /* 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 k_sigaction ka;
	siginfo_t info;
	sigset_t *oldset;
	int signr;

	/*
	 * We want the common case to go fast, which
	 * is why we may in certain cases get here from
	 * kernel mode. Just return without doing anything
	 * if so.
	 */
	if (!user_mode(__frame))
		return;

	if (try_to_freeze())
		goto no_signal;

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, __frame, NULL);
	if (signr > 0) {
		if (handle_signal(signr, &info, &ka, oldset) == 0) {
			/* a signal was successfully delivered; the saved
			 * sigmask will have been stored in the signal frame,
			 * and will be restored by sigreturn, so we can simply
			 * clear the TIF_RESTORE_SIGMASK flag */
			if (test_thread_flag(TIF_RESTORE_SIGMASK))
				clear_thread_flag(TIF_RESTORE_SIGMASK);
		}

		return;
	}

no_signal:
	/* Did we come from a system call? */
	if (__frame->syscallno >= 0) {
		/* 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->gr8 = __NR_restart_syscall;
			__frame->pc -= 4;
			break;
		}
	}

	/* if there's no signal to deliver, we just put the saved sigmask
	 * back */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}

} /* 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 | _TIF_RESTORE_SIGMASK))
		do_signal();

} /* 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>
	16	#include <linux/smp_lock.h>
	17	#include <linux/kernel.h>
	18	#include <linux/signal.h>
	19	#include <linux/errno.h>
	20	#include <linux/wait.h>
	21	#include <linux/ptrace.h>
	22	#include <linux/unistd.h>
	23	#include <linux/personality.h>
7dfb7103	24	#include <linux/freezer.h>
1da177e4 LT	25	#include <asm/ucontext.h>
	26	#include <asm/uaccess.h>
	27	#include <asm/cacheflush.h>
	28
	29	#define DEBUG_SIG 0
	30
	31	#define _BLOCKABLE (~(sigmask(SIGKILL) \| sigmask(SIGSTOP)))
	32
	33	struct fdpic_func_descriptor {
	34	unsigned long text;
	35	unsigned long GOT;
	36	};
	37
1da177e4 LT	38	/*
	39	* Atomically swap in the new signal mask, and wait for a signal.
	40	*/
	41	asmlinkage int sys_sigsuspend(int history0, int history1, old_sigset_t mask)
	42	{
1da177e4 LT	43	mask &= _BLOCKABLE;
1da177e4 LT	44	spin_lock_irq(&current->sighand->siglock);
a411aee9	45	current->saved_sigmask = current->blocked;
1da177e4 LT	46	siginitset(&current->blocked, mask);
	47	recalc_sigpending();
	48	spin_unlock_irq(&current->sighand->siglock);
	49
a411aee9 DH	50	current->state = TASK_INTERRUPTIBLE;
	51	schedule();
	52	set_thread_flag(TIF_RESTORE_SIGMASK);
	53	return -ERESTARTNOHAND;
1da177e4 LT	54	}
	55
	56	asmlinkage int sys_sigaction(int sig,
	57	const struct old_sigaction __user *act,
	58	struct old_sigaction __user *oact)
	59	{
	60	struct k_sigaction new_ka, old_ka;
	61	int ret;
	62
	63	if (act) {
	64	old_sigset_t mask;
	65	if (!access_ok(VERIFY_READ, act, sizeof(*act)) \|\|
	66	__get_user(new_ka.sa.sa_handler, &act->sa_handler) \|\|
	67	__get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
	68	return -EFAULT;
	69	__get_user(new_ka.sa.sa_flags, &act->sa_flags);
	70	__get_user(mask, &act->sa_mask);
	71	siginitset(&new_ka.sa.sa_mask, mask);
	72	}
	73
	74	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	75
	76	if (!ret && oact) {
	77	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) \|\|
	78	__put_user(old_ka.sa.sa_handler, &oact->sa_handler) \|\|
	79	__put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
	80	return -EFAULT;
	81	__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	82	__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
	83	}
	84
	85	return ret;
	86	}
	87
	88	asmlinkage
	89	int sys_sigaltstack(const stack_t __user uss, stack_t __user uoss)
	90	{
	91	return do_sigaltstack(uss, uoss, __frame->sp);
	92	}
	93
	94
	95	/*
	96	* Do a signal return; undo the signal stack.
	97	*/
	98
	99	struct sigframe
	100	{
9e4d11f8	101	__sigrestore_t pretcode;
1da177e4 LT	102	int sig;
	103	struct sigcontext sc;
	104	unsigned long extramask[_NSIG_WORDS-1];
	105	uint32_t retcode[2];
	106	};
	107
	108	struct rt_sigframe
	109	{
9e4d11f8	110	__sigrestore_t pretcode;
1da177e4	111	int sig;
9e4d11f8 AV	112	struct siginfo __user *pinfo;
9e4d11f8 AV	113	void __user *puc;
1da177e4 LT	114	struct siginfo info;
	115	struct ucontext uc;
	116	uint32_t retcode[2];
	117	};
	118
	119	static int restore_sigcontext(struct sigcontext __user sc, int _gr8)
	120	{
	121	struct user_context *user = current->thread.user;
	122	unsigned long tbr, psr;
	123
	124	tbr = user->i.tbr;
	125	psr = user->i.psr;
	126	if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))
	127	goto badframe;
	128	user->i.tbr = tbr;
	129	user->i.psr = psr;
	130
	131	restore_user_regs(user);
	132
	133	user->i.syscallno = -1; /* disable syscall checks */
	134
	135	*_gr8 = user->i.gr[8];
	136	return 0;
	137
	138	badframe:
	139	return 1;
	140	}
	141
	142	asmlinkage int sys_sigreturn(void)
	143	{
	144	struct sigframe __user frame = (struct sigframe __user ) __frame->sp;
	145	sigset_t set;
	146	int gr8;
	147
	148	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	149	goto badframe;
	150	if (__get_user(set.sig[0], &frame->sc.sc_oldmask))
	151	goto badframe;
	152
	153	if (_NSIG_WORDS > 1 &&
	154	__copy_from_user(&set.sig[1], &frame->extramask, sizeof(frame->extramask)))
	155	goto badframe;
	156
	157	sigdelsetmask(&set, ~_BLOCKABLE);
	158	spin_lock_irq(&current->sighand->siglock);
	159	current->blocked = set;
	160	recalc_sigpending();
	161	spin_unlock_irq(&current->sighand->siglock);
	162
	163	if (restore_sigcontext(&frame->sc, &gr8))
	164	goto badframe;
	165	return gr8;
	166
	167	badframe:
	168	force_sig(SIGSEGV, current);
	169	return 0;
	170	}
	171
	172	asmlinkage int sys_rt_sigreturn(void)
	173	{
	174	struct rt_sigframe __user frame = (struct rt_sigframe __user ) __frame->sp;
	175	sigset_t set;
	176	int gr8;
	177
178	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
179	goto badframe;
180	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
181	goto badframe;
182
183	sigdelsetmask(&set, ~_BLOCKABLE);
184	spin_lock_irq(&current->sighand->siglock);
185	current->blocked = set;
186	recalc_sigpending();
187	spin_unlock_irq(&current->sighand->siglock);
188
189	if (restore_sigcontext(&frame->uc.uc_mcontext, &gr8))
190	goto badframe;
191
192	if (do_sigaltstack(&frame->uc.uc_stack, NULL, __frame->sp) == -EFAULT)
193	goto badframe;
194
195	return gr8;
196
197	badframe:
198	force_sig(SIGSEGV, current);
199	return 0;
200	}
201
202	/*
203	* Set up a signal frame
204	*/
205	static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
206	{
207	save_user_regs(current->thread.user);
208
209	if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
210	goto badframe;
211
212	/* non-iBCS2 extensions.. */
213	if (__put_user(mask, &sc->sc_oldmask) < 0)
214	goto badframe;
215
216	return 0;
217
218	badframe:
219	return 1;
220	}
221
222	/*****************************************************************************/
223	/*
224	* Determine which stack to use..
225	*/
226	static inline void __user get_sigframe(struct k_sigaction ka,
1da177e4 LT	227	size_t frame_size)
	228	{
	229	unsigned long sp;
	230
	231	/* Default to using normal stack */
fef2b580	232	sp = __frame->sp;
1da177e4 LT	233
	234	/* This is the X/Open sanctioned signal stack switching. */
	235	if (ka->sa.sa_flags & SA_ONSTACK) {
d09042da	236	if (! sas_ss_flags(sp))
1da177e4 LT	237	sp = current->sas_ss_sp + current->sas_ss_size;
	238	}
	239
	240	return (void __user *) ((sp - frame_size) & ~7UL);
fef2b580	241
1da177e4 LT	242	} /* end get_sigframe() */
	243
	244	/*****************************************************************************/
	245	/*
	246	*
	247	*/
fef2b580	248	static int setup_frame(int sig, struct k_sigaction ka, sigset_t set)
1da177e4 LT	249	{
	250	struct sigframe __user *frame;
	251	int rsig;
	252
fef2b580	253	frame = get_sigframe(ka, sizeof(*frame));
1da177e4 LT	254
	255	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	256	goto give_sigsegv;
	257
	258	rsig = sig;
	259	if (sig < 32 &&
	260	__current_thread_info->exec_domain &&
	261	__current_thread_info->exec_domain->signal_invmap)
	262	rsig = __current_thread_info->exec_domain->signal_invmap[sig];
	263
	264	if (__put_user(rsig, &frame->sig) < 0)
	265	goto give_sigsegv;
	266
	267	if (setup_sigcontext(&frame->sc, set->sig[0]))
	268	goto give_sigsegv;
	269
	270	if (_NSIG_WORDS > 1) {
	271	if (__copy_to_user(frame->extramask, &set->sig[1],
	272	sizeof(frame->extramask)))
	273	goto give_sigsegv;
	274	}
	275
	276	/* Set up to return from userspace. If provided, use a stub
	277	* already in userspace. */
	278	if (ka->sa.sa_flags & SA_RESTORER) {
	279	if (__put_user(ka->sa.sa_restorer, &frame->pretcode) < 0)
	280	goto give_sigsegv;
	281	}
	282	else {
	283	/* Set up the following code on the stack:
	284	* setlos #__NR_sigreturn,gr7
	285	* tira gr0,0
	286	*/
9e4d11f8	287	if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) \|\|
1da177e4 LT	288	__put_user(0x8efc0000\|__NR_sigreturn, &frame->retcode[0]) \|\|
	289	__put_user(0xc0700000, &frame->retcode[1]))
	290	goto give_sigsegv;
	291
	292	flush_icache_range((unsigned long) frame->retcode,
	293	(unsigned long) (frame->retcode + 2));
	294	}
	295
	296	/* set up registers for signal handler */
fef2b580 DH	297	__frame->sp = (unsigned long) frame;
	298	__frame->lr = (unsigned long) &frame->retcode;
	299	__frame->gr8 = sig;
1da177e4 LT	300
	301	if (get_personality & FDPIC_FUNCPTRS) {
	302	struct fdpic_func_descriptor __user *funcptr =
9e4d11f8	303	(struct fdpic_func_descriptor __user *) ka->sa.sa_handler;
fef2b580 DH	304	__get_user(__frame->pc, &funcptr->text);
fef2b580 DH	305	__get_user(__frame->gr15, &funcptr->GOT);
1da177e4	306	} else {
fef2b580 DH	307	__frame->pc = (unsigned long) ka->sa.sa_handler;
fef2b580 DH	308	__frame->gr15 = 0;
1da177e4 LT	309	}
	310
	311	set_fs(USER_DS);
	312
8efc0ab5 DH	313	/* the tracer may want to single-step inside the handler */
	314	if (test_thread_flag(TIF_SINGLESTEP))
	315	ptrace_notify(SIGTRAP);
	316
1da177e4 LT	317	#if DEBUG_SIG
1da177e4 LT	318	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
fef2b580	319	sig, current->comm, current->pid, frame, __frame->pc,
8efc0ab5	320	frame->pretcode);
1da177e4 LT	321	#endif
1da177e4 LT	322
a411aee9	323	return 0;
1da177e4 LT	324
1da177e4 LT	325	give_sigsegv:
1da177e4	326	force_sig(SIGSEGV, current);
a411aee9	327	return -EFAULT;
8efc0ab5	328
1da177e4 LT	329	} /* end setup_frame() */
	330
	331	/*****************************************************************************/
	332	/*
	333	*
	334	*/
8efc0ab5	335	static int setup_rt_frame(int sig, struct k_sigaction ka, siginfo_t info,
fef2b580	336	sigset_t *set)
1da177e4 LT	337	{
	338	struct rt_sigframe __user *frame;
	339	int rsig;
	340
fef2b580	341	frame = get_sigframe(ka, sizeof(*frame));
1da177e4 LT	342
	343	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	344	goto give_sigsegv;
	345
	346	rsig = sig;
	347	if (sig < 32 &&
	348	__current_thread_info->exec_domain &&
	349	__current_thread_info->exec_domain->signal_invmap)
	350	rsig = __current_thread_info->exec_domain->signal_invmap[sig];
	351
	352	if (__put_user(rsig, &frame->sig) \|\|
	353	__put_user(&frame->info, &frame->pinfo) \|\|
	354	__put_user(&frame->uc, &frame->puc))
	355	goto give_sigsegv;
	356
	357	if (copy_siginfo_to_user(&frame->info, info))
	358	goto give_sigsegv;
	359
	360	/* Create the ucontext. */
	361	if (__put_user(0, &frame->uc.uc_flags) \|\|
9e4d11f8 AV	362	__put_user(NULL, &frame->uc.uc_link) \|\|
9e4d11f8 AV	363	__put_user((void __user *)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp) \|\|
fef2b580	364	__put_user(sas_ss_flags(__frame->sp), &frame->uc.uc_stack.ss_flags) \|\|
1da177e4 LT	365	__put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size))
	366	goto give_sigsegv;
	367
	368	if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
	369	goto give_sigsegv;
	370
	371	if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
	372	goto give_sigsegv;
	373
	374	/* Set up to return from userspace. If provided, use a stub
	375	* already in userspace. */
	376	if (ka->sa.sa_flags & SA_RESTORER) {
	377	if (__put_user(ka->sa.sa_restorer, &frame->pretcode))
	378	goto give_sigsegv;
	379	}
	380	else {
	381	/* Set up the following code on the stack:
	382	* setlos #__NR_sigreturn,gr7
	383	* tira gr0,0
	384	*/
9e4d11f8	385	if (__put_user((__sigrestore_t)frame->retcode, &frame->pretcode) \|\|
1da177e4 LT	386	__put_user(0x8efc0000\|__NR_rt_sigreturn, &frame->retcode[0]) \|\|
	387	__put_user(0xc0700000, &frame->retcode[1]))
	388	goto give_sigsegv;
	389
	390	flush_icache_range((unsigned long) frame->retcode,
	391	(unsigned long) (frame->retcode + 2));
	392	}
	393
	394	/* Set up registers for signal handler */
fef2b580 DH	395	__frame->sp = (unsigned long) frame;
	396	__frame->lr = (unsigned long) &frame->retcode;
	397	__frame->gr8 = sig;
	398	__frame->gr9 = (unsigned long) &frame->info;
1da177e4 LT	399
1da177e4 LT	400	if (get_personality & FDPIC_FUNCPTRS) {
9e4d11f8	401	struct fdpic_func_descriptor __user *funcptr =
1da177e4	402	(struct fdpic_func_descriptor __user *) ka->sa.sa_handler;
fef2b580 DH	403	__get_user(__frame->pc, &funcptr->text);
fef2b580 DH	404	__get_user(__frame->gr15, &funcptr->GOT);
1da177e4	405	} else {
fef2b580 DH	406	__frame->pc = (unsigned long) ka->sa.sa_handler;
fef2b580 DH	407	__frame->gr15 = 0;
1da177e4 LT	408	}
	409
	410	set_fs(USER_DS);
	411
8efc0ab5 DH	412	/* the tracer may want to single-step inside the handler */
	413	if (test_thread_flag(TIF_SINGLESTEP))
	414	ptrace_notify(SIGTRAP);
	415
1da177e4 LT	416	#if DEBUG_SIG
1da177e4 LT	417	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
fef2b580	418	sig, current->comm, current->pid, frame, __frame->pc,
8efc0ab5	419	frame->pretcode);
1da177e4 LT	420	#endif
1da177e4 LT	421
a411aee9	422	return 0;
1da177e4 LT	423
1da177e4 LT	424	give_sigsegv:
1da177e4	425	force_sig(SIGSEGV, current);
a411aee9	426	return -EFAULT;
1da177e4 LT	427
	428	} /* end setup_rt_frame() */
	429
	430	/*****************************************************************************/
	431	/*
	432	* OK, we're invoking a handler
	433	*/
8efc0ab5	434	static int handle_signal(unsigned long sig, siginfo_t *info,
fef2b580	435	struct k_sigaction ka, sigset_t oldset)
1da177e4	436	{
8efc0ab5 DH	437	int ret;
8efc0ab5 DH	438
1da177e4	439	/* Are we from a system call? */
fef2b580	440	if (in_syscall(__frame)) {
1da177e4	441	/* If so, check system call restarting.. */
fef2b580	442	switch (__frame->gr8) {
1da177e4 LT	443	case -ERESTART_RESTARTBLOCK:
1da177e4 LT	444	case -ERESTARTNOHAND:
fef2b580	445	__frame->gr8 = -EINTR;
1da177e4 LT	446	break;
	447
	448	case -ERESTARTSYS:
	449	if (!(ka->sa.sa_flags & SA_RESTART)) {
fef2b580	450	__frame->gr8 = -EINTR;
1da177e4 LT	451	break;
1da177e4 LT	452	}
8efc0ab5	453
1da177e4 LT	454	/* fallthrough */
1da177e4 LT	455	case -ERESTARTNOINTR:
fef2b580 DH	456	__frame->gr8 = __frame->orig_gr8;
fef2b580 DH	457	__frame->pc -= 4;
1da177e4 LT	458	}
	459	}
	460
	461	/* Set up the stack frame */
	462	if (ka->sa.sa_flags & SA_SIGINFO)
fef2b580	463	ret = setup_rt_frame(sig, ka, info, oldset);
1da177e4	464	else
fef2b580	465	ret = setup_frame(sig, ka, oldset);
8efc0ab5	466
a411aee9	467	if (ret == 0) {
8efc0ab5 DH	468	spin_lock_irq(&current->sighand->siglock);
	469	sigorsets(&current->blocked, &current->blocked,
	470	&ka->sa.sa_mask);
	471	if (!(ka->sa.sa_flags & SA_NODEFER))
	472	sigaddset(&current->blocked, sig);
	473	recalc_sigpending();
	474	spin_unlock_irq(&current->sighand->siglock);
	475	}
	476
	477	return ret;
1da177e4	478
1da177e4 LT	479	} /* end handle_signal() */
	480
	481	/*****************************************************************************/
	482	/*
	483	* Note that 'init' is a special process: it doesn't get signals it doesn't
	484	* want to handle. Thus you cannot kill init even with a SIGKILL even by
	485	* mistake.
	486	*/
a411aee9	487	static void do_signal(void)
1da177e4 LT	488	{
	489	struct k_sigaction ka;
	490	siginfo_t info;
a411aee9	491	sigset_t *oldset;
1da177e4 LT	492	int signr;
	493
	494	/*
	495	* We want the common case to go fast, which
	496	* is why we may in certain cases get here from
	497	* kernel mode. Just return without doing anything
	498	* if so.
	499	*/
fef2b580	500	if (!user_mode(__frame))
a411aee9	501	return;
1da177e4	502
3e1d1d28	503	if (try_to_freeze())
1da177e4	504	goto no_signal;
1da177e4	505
a411aee9 DH	506	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	507	oldset = &current->saved_sigmask;
	508	else
1da177e4 LT	509	oldset = &current->blocked;
1da177e4 LT	510
fef2b580	511	signr = get_signal_to_deliver(&info, &ka, __frame, NULL);
a411aee9 DH	512	if (signr > 0) {
	513	if (handle_signal(signr, &info, &ka, oldset) == 0) {
	514	/* a signal was successfully delivered; the saved
	515	* sigmask will have been stored in the signal frame,
	516	* and will be restored by sigreturn, so we can simply
	517	* clear the TIF_RESTORE_SIGMASK flag */
	518	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	519	clear_thread_flag(TIF_RESTORE_SIGMASK);
	520	}
	521
	522	return;
	523	}
1da177e4	524
8efc0ab5	525	no_signal:
1da177e4	526	/* Did we come from a system call? */
fef2b580	527	if (__frame->syscallno >= 0) {
1da177e4	528	/* Restart the system call - no handlers present */
a411aee9 DH	529	switch (__frame->gr8) {
	530	case -ERESTARTNOHAND:
	531	case -ERESTARTSYS:
	532	case -ERESTARTNOINTR:
fef2b580 DH	533	__frame->gr8 = __frame->orig_gr8;
fef2b580 DH	534	__frame->pc -= 4;
a411aee9	535	break;
1da177e4	536
a411aee9	537	case -ERESTART_RESTARTBLOCK:
fef2b580 DH	538	__frame->gr8 = __NR_restart_syscall;
fef2b580 DH	539	__frame->pc -= 4;
a411aee9	540	break;
1da177e4 LT	541	}
	542	}
	543
a411aee9 DH	544	/* if there's no signal to deliver, we just put the saved sigmask
	545	* back */
	546	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
	547	clear_thread_flag(TIF_RESTORE_SIGMASK);
	548	sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	549	}
8efc0ab5	550
1da177e4 LT	551	} /* end do_signal() */
	552
	553	/*****************************************************************************/
	554	/*
	555	* notification of userspace execution resumption
a411aee9	556	* - triggered by the TIF_WORK_MASK flags
1da177e4 LT	557	*/
	558	asmlinkage void do_notify_resume(__u32 thread_info_flags)
	559	{
	560	/* pending single-step? */
	561	if (thread_info_flags & _TIF_SINGLESTEP)
	562	clear_thread_flag(TIF_SINGLESTEP);
	563
	564	/* deal with pending signal delivery */
a411aee9 DH	565	if (thread_info_flags & (_TIF_SIGPENDING \| _TIF_RESTORE_SIGMASK))
a411aee9 DH	566	do_signal();
1da177e4 LT	567
1da177e4 LT	568	} /* end do_notify_resume() */