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

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1991, 1992  Linus Torvalds
 * Copyright (C) 1994 - 2000  Ralf Baechle
 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
 */
#include <linux/config.h>
#include <linux/cache.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/personality.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/compiler.h>

#include <asm/abi.h>
#include <asm/asm.h>
#include <linux/bitops.h>
#include <asm/cacheflush.h>
#include <asm/fpu.h>
#include <asm/sim.h>
#include <asm/uaccess.h>
#include <asm/ucontext.h>
#include <asm/cpu-features.h>
#include <asm/war.h>

#include "signal-common.h"

#define DEBUG_SIG 0

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

int do_signal(sigset_t *oldset, struct pt_regs *regs);

/*
 * Atomically swap in the new signal mask, and wait for a signal.
 */

#ifdef CONFIG_TRAD_SIGNALS
save_static_function(sys_sigsuspend);
__attribute_used__ noinline static int
_sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
{
	sigset_t saveset, newset;
	sigset_t __user *uset;

	uset = (sigset_t __user *) regs.regs[4];
	if (copy_from_user(&newset, uset, sizeof(sigset_t)))
		return -EFAULT;
	sigdelsetmask(&newset, ~_BLOCKABLE);

	spin_lock_irq(&current->sighand->siglock);
	saveset = current->blocked;
	current->blocked = newset;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	regs.regs[2] = EINTR;
	regs.regs[7] = 1;
	while (1) {
		current->state = TASK_INTERRUPTIBLE;
		schedule();
		if (do_signal(&saveset, &regs))
			return -EINTR;
	}
}
#endif

save_static_function(sys_rt_sigsuspend);
__attribute_used__ noinline static int
_sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
{
	sigset_t saveset, newset;
	sigset_t __user *unewset;
	size_t sigsetsize;

	/* XXX Don't preclude handling different sized sigset_t's.  */
	sigsetsize = regs.regs[5];
	if (sigsetsize != sizeof(sigset_t))
		return -EINVAL;

	unewset = (sigset_t __user *) regs.regs[4];
	if (copy_from_user(&newset, unewset, sizeof(newset)))
		return -EFAULT;
	sigdelsetmask(&newset, ~_BLOCKABLE);

	spin_lock_irq(&current->sighand->siglock);
	saveset = current->blocked;
	current->blocked = newset;
        recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	regs.regs[2] = EINTR;
	regs.regs[7] = 1;
	while (1) {
		current->state = TASK_INTERRUPTIBLE;
		schedule();
		if (do_signal(&saveset, &regs))
			return -EINTR;
	}
}

#ifdef CONFIG_TRAD_SIGNALS
asmlinkage int sys_sigaction(int sig, const struct sigaction *act,
	struct sigaction *oact)
{
	struct k_sigaction new_ka, old_ka;
	int ret;
	int err = 0;

	if (act) {
		old_sigset_t mask;

		if (!access_ok(VERIFY_READ, act, sizeof(*act)))
			return -EFAULT;
		err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
		err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
		err |= __get_user(mask, &act->sa_mask.sig[0]);
		if (err)
			return -EFAULT;

		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)))
                        return -EFAULT;
		err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
		err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
		err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
		err |= __put_user(0, &oact->sa_mask.sig[1]);
		err |= __put_user(0, &oact->sa_mask.sig[2]);
		err |= __put_user(0, &oact->sa_mask.sig[3]);
		if (err)
			return -EFAULT;
	}

	return ret;
}
#endif

asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
{
	const stack_t __user *uss = (const stack_t __user *) regs.regs[4];
	stack_t __user *uoss = (stack_t __user *) regs.regs[5];
	unsigned long usp = regs.regs[29];

	return do_sigaltstack(uss, uoss, usp);
}

/*
 * Horribly complicated - with the bloody RM9000 workarounds enabled
 * the signal trampolines is moving to the end of the structure so we can
 * increase the alignment without breaking software compatibility.
 */
#ifdef CONFIG_TRAD_SIGNALS
struct sigframe {
	u32 sf_ass[4];			/* argument save space for o32 */
#if ICACHE_REFILLS_WORKAROUND_WAR
	u32 sf_pad[2];
#else
	u32 sf_code[2];			/* signal trampoline */
#endif
	struct sigcontext sf_sc;
	sigset_t sf_mask;
#if ICACHE_REFILLS_WORKAROUND_WAR
	u32 sf_code[8] ____cacheline_aligned;	/* signal trampoline */
#endif
};
#endif

struct rt_sigframe {
	u32 rs_ass[4];			/* argument save space for o32 */
#if ICACHE_REFILLS_WORKAROUND_WAR
	u32 rs_pad[2];
#else
	u32 rs_code[2];			/* signal trampoline */
#endif
	struct siginfo rs_info;
	struct ucontext rs_uc;
#if ICACHE_REFILLS_WORKAROUND_WAR
	u32 rs_code[8] ____cacheline_aligned;	/* signal trampoline */
#endif
};

#ifdef CONFIG_TRAD_SIGNALS
save_static_function(sys_sigreturn);
__attribute_used__ noinline static void
_sys_sigreturn(nabi_no_regargs struct pt_regs regs)
{
	struct sigframe __user *frame;
	sigset_t blocked;

	frame = (struct sigframe __user *) regs.regs[29];
	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
		goto badframe;
	if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
		goto badframe;

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

	if (restore_sigcontext(&regs, &frame->sf_sc))
		goto badframe;

	/*
	 * Don't let your children do this ...
	 */
	__asm__ __volatile__(
		"move\t$29, %0\n\t"
		"j\tsyscall_exit"
		:/* no outputs */
		:"r" (&regs));
	/* Unreached */

badframe:
	force_sig(SIGSEGV, current);
}
#endif /* CONFIG_TRAD_SIGNALS */

save_static_function(sys_rt_sigreturn);
__attribute_used__ noinline static void
_sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
{
	struct rt_sigframe __user *frame;
	sigset_t set;
	stack_t st;

	frame = (struct rt_sigframe __user *) regs.regs[29];
	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
		goto badframe;
	if (__copy_from_user(&set, &frame->rs_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(&regs, &frame->rs_uc.uc_mcontext))
		goto badframe;

	if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
		goto badframe;
	/* It is more difficult to avoid calling this function than to
	   call it and ignore errors.  */
	do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);

	/*
	 * Don't let your children do this ...
	 */
	__asm__ __volatile__(
		"move\t$29, %0\n\t"
		"j\tsyscall_exit"
		:/* no outputs */
		:"r" (&regs));
	/* Unreached */

badframe:
	force_sig(SIGSEGV, current);
}

#ifdef CONFIG_TRAD_SIGNALS
int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
	int signr, sigset_t *set)
{
	struct sigframe __user *frame;
	int err = 0;

	frame = get_sigframe(ka, regs, sizeof(*frame));
	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
		goto give_sigsegv;

	install_sigtramp(frame->sf_code, __NR_sigreturn);

	err |= setup_sigcontext(regs, &frame->sf_sc);
	err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
	if (err)
		goto give_sigsegv;

	/*
	 * Arguments to signal handler:
	 *
	 *   a0 = signal number
	 *   a1 = 0 (should be cause)
	 *   a2 = pointer to struct sigcontext
	 *
	 * $25 and c0_epc point to the signal handler, $29 points to the
	 * struct sigframe.
	 */
	regs->regs[ 4] = signr;
	regs->regs[ 5] = 0;
	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
	regs->regs[29] = (unsigned long) frame;
	regs->regs[31] = (unsigned long) frame->sf_code;
	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;

#if DEBUG_SIG
	printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
	       current->comm, current->pid,
	       frame, regs->cp0_epc, frame->regs[31]);
#endif
        return 1;

give_sigsegv:
	force_sigsegv(signr, current);
	return 0;
}
#endif

int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
	int signr, sigset_t *set, siginfo_t *info)
{
	struct rt_sigframe __user *frame;
	int err = 0;

	frame = get_sigframe(ka, regs, sizeof(*frame));
	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
		goto give_sigsegv;

	install_sigtramp(frame->rs_code, __NR_rt_sigreturn);

	/* Create siginfo.  */
	err |= copy_siginfo_to_user(&frame->rs_info, info);

	/* Create the ucontext.  */
	err |= __put_user(0, &frame->rs_uc.uc_flags);
	err |= __put_user(NULL, &frame->rs_uc.uc_link);
	err |= __put_user((void *)current->sas_ss_sp,
	                  &frame->rs_uc.uc_stack.ss_sp);
	err |= __put_user(sas_ss_flags(regs->regs[29]),
	                  &frame->rs_uc.uc_stack.ss_flags);
	err |= __put_user(current->sas_ss_size,
	                  &frame->rs_uc.uc_stack.ss_size);
	err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));

	if (err)
		goto give_sigsegv;

	/*
	 * Arguments to signal handler:
	 *
	 *   a0 = signal number
	 *   a1 = 0 (should be cause)
	 *   a2 = pointer to ucontext
	 *
	 * $25 and c0_epc point to the signal handler, $29 points to
	 * the struct rt_sigframe.
	 */
	regs->regs[ 4] = signr;
	regs->regs[ 5] = (unsigned long) &frame->rs_info;
	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
	regs->regs[29] = (unsigned long) frame;
	regs->regs[31] = (unsigned long) frame->rs_code;
	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;

#if DEBUG_SIG
	printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
	       current->comm, current->pid,
	       frame, regs->cp0_epc, regs->regs[31]);
#endif
	return 1;

give_sigsegv:
	force_sigsegv(signr, current);
	return 0;
}

static inline int handle_signal(unsigned long sig, siginfo_t *info,
	struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
{
	int ret;

	switch(regs->regs[0]) {
	case ERESTART_RESTARTBLOCK:
	case ERESTARTNOHAND:
		regs->regs[2] = EINTR;
		break;
	case ERESTARTSYS:
		if(!(ka->sa.sa_flags & SA_RESTART)) {
			regs->regs[2] = EINTR;
			break;
		}
	/* fallthrough */
	case ERESTARTNOINTR:		/* Userland will reload $v0.  */
		regs->regs[7] = regs->regs[26];
		regs->cp0_epc -= 8;
	}

	regs->regs[0] = 0;		/* Don't deal with this again.  */

	if (sig_uses_siginfo(ka))
		ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
	else
		ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);

	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;
}

int do_signal(sigset_t *oldset, struct pt_regs *regs)
{
	struct k_sigaction ka;
	siginfo_t info;
	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(regs))
		return 1;

	if (try_to_freeze())
		goto no_signal;

	if (!oldset)
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	if (signr > 0)
		return handle_signal(signr, &info, &ka, oldset, regs);

no_signal:
	/*
	 * Who's code doesn't conform to the restartable syscall convention
	 * dies here!!!  The li instruction, a single machine instruction,
	 * must directly be followed by the syscall instruction.
	 */
	if (regs->regs[0]) {
		if (regs->regs[2] == ERESTARTNOHAND ||
		    regs->regs[2] == ERESTARTSYS ||
		    regs->regs[2] == ERESTARTNOINTR) {
			regs->regs[7] = regs->regs[26];
			regs->cp0_epc -= 8;
		}
		if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
			regs->regs[2] = __NR_restart_syscall;
			regs->regs[7] = regs->regs[26];
			regs->cp0_epc -= 4;
		}
	}
	return 0;
}

/*
 * notification of userspace execution resumption
 * - triggered by current->work.notify_resume
 */
asmlinkage void do_notify_resume(struct pt_regs *regs, sigset_t *oldset,
	__u32 thread_info_flags)
{
	/* deal with pending signal delivery */
	if (thread_info_flags & _TIF_SIGPENDING) {
		current->thread.abi->do_signal(oldset, regs);
	}
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* This file is subject to the terms and conditions of the GNU General Public
	3	* License. See the file "COPYING" in the main directory of this archive
	4	* for more details.
	5	*
	6	* Copyright (C) 1991, 1992 Linus Torvalds
	7	* Copyright (C) 1994 - 2000 Ralf Baechle
	8	* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
	9	*/
	10	#include <linux/config.h>
02416dcf	11	#include <linux/cache.h>
1da177e4 LT	12	#include <linux/sched.h>
	13	#include <linux/mm.h>
	14	#include <linux/personality.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/compiler.h>
	24
e50c0a8f	25	#include <asm/abi.h>
1da177e4 LT	26	#include <asm/asm.h>
	27	#include <linux/bitops.h>
	28	#include <asm/cacheflush.h>
	29	#include <asm/fpu.h>
	30	#include <asm/sim.h>
	31	#include <asm/uaccess.h>
	32	#include <asm/ucontext.h>
	33	#include <asm/cpu-features.h>
02416dcf	34	#include <asm/war.h>
1da177e4 LT	35
	36	#include "signal-common.h"
	37
	38	#define DEBUG_SIG 0
	39
	40	#define _BLOCKABLE (~(sigmask(SIGKILL) \| sigmask(SIGSTOP)))
	41
e50c0a8f	42	int do_signal(sigset_t oldset, struct pt_regs regs);
1da177e4 LT	43
	44	/*
	45	* Atomically swap in the new signal mask, and wait for a signal.
	46	*/
	47
	48	#ifdef CONFIG_TRAD_SIGNALS
	49	save_static_function(sys_sigsuspend);
	50	__attribute_used__ noinline static int
	51	_sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
	52	{
fe00f943 RB	53	sigset_t saveset, newset;
fe00f943 RB	54	sigset_t __user *uset;
1da177e4	55
fe00f943	56	uset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	57	if (copy_from_user(&newset, uset, sizeof(sigset_t)))
	58	return -EFAULT;
	59	sigdelsetmask(&newset, ~_BLOCKABLE);
	60
	61	spin_lock_irq(&current->sighand->siglock);
	62	saveset = current->blocked;
	63	current->blocked = newset;
	64	recalc_sigpending();
	65	spin_unlock_irq(&current->sighand->siglock);
	66
	67	regs.regs[2] = EINTR;
	68	regs.regs[7] = 1;
	69	while (1) {
	70	current->state = TASK_INTERRUPTIBLE;
	71	schedule();
	72	if (do_signal(&saveset, &regs))
	73	return -EINTR;
	74	}
	75	}
	76	#endif
	77
	78	save_static_function(sys_rt_sigsuspend);
	79	__attribute_used__ noinline static int
	80	_sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
	81	{
fe00f943 RB	82	sigset_t saveset, newset;
fe00f943 RB	83	sigset_t __user *unewset;
1da177e4 LT	84	size_t sigsetsize;
	85
	86	/* XXX Don't preclude handling different sized sigset_t's. */
	87	sigsetsize = regs.regs[5];
	88	if (sigsetsize != sizeof(sigset_t))
	89	return -EINVAL;
	90
fe00f943	91	unewset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	92	if (copy_from_user(&newset, unewset, sizeof(newset)))
	93	return -EFAULT;
	94	sigdelsetmask(&newset, ~_BLOCKABLE);
	95
	96	spin_lock_irq(&current->sighand->siglock);
	97	saveset = current->blocked;
	98	current->blocked = newset;
	99	recalc_sigpending();
	100	spin_unlock_irq(&current->sighand->siglock);
	101
	102	regs.regs[2] = EINTR;
	103	regs.regs[7] = 1;
	104	while (1) {
	105	current->state = TASK_INTERRUPTIBLE;
	106	schedule();
	107	if (do_signal(&saveset, &regs))
	108	return -EINTR;
	109	}
	110	}
	111
	112	#ifdef CONFIG_TRAD_SIGNALS
	113	asmlinkage int sys_sigaction(int sig, const struct sigaction *act,
	114	struct sigaction *oact)
	115	{
	116	struct k_sigaction new_ka, old_ka;
	117	int ret;
	118	int err = 0;
	119
	120	if (act) {
	121	old_sigset_t mask;
	122
	123	if (!access_ok(VERIFY_READ, act, sizeof(*act)))
	124	return -EFAULT;
	125	err \|= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
	126	err \|= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
	127	err \|= __get_user(mask, &act->sa_mask.sig[0]);
	128	if (err)
	129	return -EFAULT;
	130
	131	siginitset(&new_ka.sa.sa_mask, mask);
	132	}
	133
	134	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	135
	136	if (!ret && oact) {
	137	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
	138	return -EFAULT;
	139	err \|= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	140	err \|= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
	141	err \|= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
	142	err \|= __put_user(0, &oact->sa_mask.sig[1]);
	143	err \|= __put_user(0, &oact->sa_mask.sig[2]);
	144	err \|= __put_user(0, &oact->sa_mask.sig[3]);
	145	if (err)
	146	return -EFAULT;
	147	}
	148
	149	return ret;
	150	}
	151	#endif
	152
	153	asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
	154	{
fe00f943 RB	155	const stack_t __user uss = (const stack_t __user ) regs.regs[4];
fe00f943 RB	156	stack_t __user uoss = (stack_t __user ) regs.regs[5];
1da177e4 LT	157	unsigned long usp = regs.regs[29];
	158
	159	return do_sigaltstack(uss, uoss, usp);
	160	}
	161
02416dcf RB	162	/*
	163	* Horribly complicated - with the bloody RM9000 workarounds enabled
	164	* the signal trampolines is moving to the end of the structure so we can
	165	* increase the alignment without breaking software compatibility.
	166	*/
1da177e4 LT	167	#ifdef CONFIG_TRAD_SIGNALS
	168	struct sigframe {
	169	u32 sf_ass[4]; /* argument save space for o32 */
02416dcf RB	170	#if ICACHE_REFILLS_WORKAROUND_WAR
	171	u32 sf_pad[2];
	172	#else
	173	u32 sf_code[2]; /* signal trampoline */
	174	#endif
	175	struct sigcontext sf_sc;
1da177e4	176	sigset_t sf_mask;
02416dcf RB	177	#if ICACHE_REFILLS_WORKAROUND_WAR
	178	u32 sf_code[8] ____cacheline_aligned; /* signal trampoline */
	179	#endif
1da177e4 LT	180	};
	181	#endif
	182
	183	struct rt_sigframe {
	184	u32 rs_ass[4]; /* argument save space for o32 */
02416dcf RB	185	#if ICACHE_REFILLS_WORKAROUND_WAR
	186	u32 rs_pad[2];
	187	#else
	188	u32 rs_code[2]; /* signal trampoline */
	189	#endif
	190	struct siginfo rs_info;
1da177e4	191	struct ucontext rs_uc;
02416dcf RB	192	#if ICACHE_REFILLS_WORKAROUND_WAR
	193	u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */
	194	#endif
1da177e4 LT	195	};
	196
	197	#ifdef CONFIG_TRAD_SIGNALS
	198	save_static_function(sys_sigreturn);
	199	__attribute_used__ noinline static void
	200	_sys_sigreturn(nabi_no_regargs struct pt_regs regs)
	201	{
9bbf28a3	202	struct sigframe __user *frame;
1da177e4 LT	203	sigset_t blocked;
1da177e4 LT	204
9bbf28a3	205	frame = (struct sigframe __user *) regs.regs[29];
1da177e4 LT	206	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	207	goto badframe;
	208	if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
	209	goto badframe;
	210
	211	sigdelsetmask(&blocked, ~_BLOCKABLE);
	212	spin_lock_irq(&current->sighand->siglock);
	213	current->blocked = blocked;
	214	recalc_sigpending();
	215	spin_unlock_irq(&current->sighand->siglock);
	216
	217	if (restore_sigcontext(&regs, &frame->sf_sc))
	218	goto badframe;
	219
	220	/*
	221	* Don't let your children do this ...
	222	*/
1da177e4 LT	223	__asm__ __volatile__(
	224	"move\t$29, %0\n\t"
	225	"j\tsyscall_exit"
	226	:/* no outputs */
	227	:"r" (&regs));
	228	/* Unreached */
	229
	230	badframe:
	231	force_sig(SIGSEGV, current);
	232	}
e50c0a8f	233	#endif /* CONFIG_TRAD_SIGNALS */
1da177e4 LT	234
	235	save_static_function(sys_rt_sigreturn);
	236	__attribute_used__ noinline static void
	237	_sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
	238	{
9bbf28a3	239	struct rt_sigframe __user *frame;
1da177e4 LT	240	sigset_t set;
	241	stack_t st;
	242
9bbf28a3	243	frame = (struct rt_sigframe __user *) regs.regs[29];
1da177e4 LT	244	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	245	goto badframe;
	246	if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
	247	goto badframe;
	248
	249	sigdelsetmask(&set, ~_BLOCKABLE);
	250	spin_lock_irq(&current->sighand->siglock);
	251	current->blocked = set;
	252	recalc_sigpending();
	253	spin_unlock_irq(&current->sighand->siglock);
	254
	255	if (restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext))
	256	goto badframe;
	257
	258	if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
	259	goto badframe;
	260	/* It is more difficult to avoid calling this function than to
	261	call it and ignore errors. */
9bbf28a3	262	do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
1da177e4 LT	263
	264	/*
	265	* Don't let your children do this ...
	266	*/
	267	__asm__ __volatile__(
	268	"move\t$29, %0\n\t"
	269	"j\tsyscall_exit"
	270	:/* no outputs */
	271	:"r" (&regs));
	272	/* Unreached */
	273
	274	badframe:
	275	force_sig(SIGSEGV, current);
	276	}
	277
	278	#ifdef CONFIG_TRAD_SIGNALS
129bc8f7	279	int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
1da177e4 LT	280	int signr, sigset_t *set)
1da177e4 LT	281	{
9bbf28a3	282	struct sigframe __user *frame;
1da177e4 LT	283	int err = 0;
	284
	285	frame = get_sigframe(ka, regs, sizeof(*frame));
	286	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	287	goto give_sigsegv;
	288
02416dcf	289	install_sigtramp(frame->sf_code, __NR_sigreturn);
1da177e4 LT	290
	291	err \|= setup_sigcontext(regs, &frame->sf_sc);
	292	err \|= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
	293	if (err)
	294	goto give_sigsegv;
	295
	296	/*
	297	* Arguments to signal handler:
	298	*
	299	* a0 = signal number
	300	* a1 = 0 (should be cause)
	301	* a2 = pointer to struct sigcontext
	302	*
	303	* $25 and c0_epc point to the signal handler, $29 points to the
	304	* struct sigframe.
	305	*/
	306	regs->regs[ 4] = signr;
	307	regs->regs[ 5] = 0;
	308	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
	309	regs->regs[29] = (unsigned long) frame;
	310	regs->regs[31] = (unsigned long) frame->sf_code;
	311	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
	312
	313	#if DEBUG_SIG
	314	printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
	315	current->comm, current->pid,
	316	frame, regs->cp0_epc, frame->regs[31]);
	317	#endif
129bc8f7	318	return 1;
1da177e4 LT	319
	320	give_sigsegv:
	321	force_sigsegv(signr, current);
129bc8f7	322	return 0;
1da177e4 LT	323	}
	324	#endif
	325
129bc8f7	326	int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
1da177e4 LT	327	int signr, sigset_t set, siginfo_t info)
1da177e4 LT	328	{
9bbf28a3	329	struct rt_sigframe __user *frame;
1da177e4 LT	330	int err = 0;
	331
	332	frame = get_sigframe(ka, regs, sizeof(*frame));
	333	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	334	goto give_sigsegv;
	335
02416dcf	336	install_sigtramp(frame->rs_code, __NR_rt_sigreturn);
1da177e4 LT	337
	338	/* Create siginfo. */
	339	err \|= copy_siginfo_to_user(&frame->rs_info, info);
	340
	341	/* Create the ucontext. */
	342	err \|= __put_user(0, &frame->rs_uc.uc_flags);
5665a0ac	343	err \|= __put_user(NULL, &frame->rs_uc.uc_link);
1da177e4 LT	344	err \|= __put_user((void *)current->sas_ss_sp,
	345	&frame->rs_uc.uc_stack.ss_sp);
	346	err \|= __put_user(sas_ss_flags(regs->regs[29]),
	347	&frame->rs_uc.uc_stack.ss_flags);
	348	err \|= __put_user(current->sas_ss_size,
	349	&frame->rs_uc.uc_stack.ss_size);
	350	err \|= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	351	err \|= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
	352
	353	if (err)
	354	goto give_sigsegv;
	355
	356	/*
	357	* Arguments to signal handler:
	358	*
	359	* a0 = signal number
	360	* a1 = 0 (should be cause)
	361	* a2 = pointer to ucontext
	362	*
	363	* $25 and c0_epc point to the signal handler, $29 points to
	364	* the struct rt_sigframe.
	365	*/
	366	regs->regs[ 4] = signr;
	367	regs->regs[ 5] = (unsigned long) &frame->rs_info;
	368	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
	369	regs->regs[29] = (unsigned long) frame;
	370	regs->regs[31] = (unsigned long) frame->rs_code;
	371	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
	372
	373	#if DEBUG_SIG
	374	printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
	375	current->comm, current->pid,
	376	frame, regs->cp0_epc, regs->regs[31]);
	377	#endif
129bc8f7	378	return 1;
1da177e4 LT	379
	380	give_sigsegv:
	381	force_sigsegv(signr, current);
129bc8f7	382	return 0;
1da177e4 LT	383	}
1da177e4 LT	384
129bc8f7	385	static inline int handle_signal(unsigned long sig, siginfo_t *info,
1da177e4 LT	386	struct k_sigaction ka, sigset_t oldset, struct pt_regs *regs)
1da177e4 LT	387	{
129bc8f7 RB	388	int ret;
129bc8f7 RB	389
1da177e4 LT	390	switch(regs->regs[0]) {
	391	case ERESTART_RESTARTBLOCK:
	392	case ERESTARTNOHAND:
	393	regs->regs[2] = EINTR;
	394	break;
	395	case ERESTARTSYS:
	396	if(!(ka->sa.sa_flags & SA_RESTART)) {
	397	regs->regs[2] = EINTR;
	398	break;
	399	}
	400	/* fallthrough */
	401	case ERESTARTNOINTR: /* Userland will reload $v0. */
	402	regs->regs[7] = regs->regs[26];
	403	regs->cp0_epc -= 8;
	404	}
	405
	406	regs->regs[0] = 0; /* Don't deal with this again. */
	407
e50c0a8f	408	if (sig_uses_siginfo(ka))
129bc8f7	409	ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
1da177e4	410	else
129bc8f7	411	ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);
1da177e4	412
69be8f18 SR	413	spin_lock_irq(&current->sighand->siglock);
	414	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
	415	if (!(ka->sa.sa_flags & SA_NODEFER))
1da177e4	416	sigaddset(&current->blocked,sig);
69be8f18 SR	417	recalc_sigpending();
69be8f18 SR	418	spin_unlock_irq(&current->sighand->siglock);
129bc8f7 RB	419
129bc8f7 RB	420	return ret;
1da177e4 LT	421	}
1da177e4 LT	422
e50c0a8f	423	int do_signal(sigset_t oldset, struct pt_regs regs)
1da177e4 LT	424	{
	425	struct k_sigaction ka;
	426	siginfo_t info;
	427	int signr;
	428
1da177e4 LT	429	/*
	430	* We want the common case to go fast, which is why we may in certain
	431	* cases get here from kernel mode. Just return without doing anything
	432	* if so.
	433	*/
	434	if (!user_mode(regs))
	435	return 1;
	436
d4b3a80e	437	if (try_to_freeze())
1da177e4 LT	438	goto no_signal;
	439
	440	if (!oldset)
	441	oldset = &current->blocked;
	442
	443	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
129bc8f7 RB	444	if (signr > 0)
129bc8f7 RB	445	return handle_signal(signr, &info, &ka, oldset, regs);
1da177e4 LT	446
	447	no_signal:
	448	/*
	449	* Who's code doesn't conform to the restartable syscall convention
	450	* dies here!!! The li instruction, a single machine instruction,
	451	* must directly be followed by the syscall instruction.
	452	*/
	453	if (regs->regs[0]) {
	454	if (regs->regs[2] == ERESTARTNOHAND \|\|
	455	regs->regs[2] == ERESTARTSYS \|\|
	456	regs->regs[2] == ERESTARTNOINTR) {
	457	regs->regs[7] = regs->regs[26];
	458	regs->cp0_epc -= 8;
	459	}
	460	if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
	461	regs->regs[2] = __NR_restart_syscall;
	462	regs->regs[7] = regs->regs[26];
	463	regs->cp0_epc -= 4;
	464	}
	465	}
	466	return 0;
	467	}
	468
	469	/*
	470	* notification of userspace execution resumption
	471	* - triggered by current->work.notify_resume
	472	*/
	473	asmlinkage void do_notify_resume(struct pt_regs regs, sigset_t oldset,
	474	__u32 thread_info_flags)
	475	{
	476	/* deal with pending signal delivery */
	477	if (thread_info_flags & _TIF_SIGPENDING) {
e50c0a8f	478	current->thread.abi->do_signal(oldset, regs);
1da177e4 LT	479	}
1da177e4 LT	480	}