arch/mips/kernel/signal.c - kernel/msm-4.9 - Gitiles

 /*
  * 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 *frame;
 	sigset_t blocked;

 	frame = (struct sigframe *) 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 ...
 	 */
 	if (current_thread_info()->flags & TIF_SYSCALL_TRACE)
 		do_syscall_trace(&regs, 1);
 	__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 *frame;
 	sigset_t set;
 	stack_t st;

 	frame = (struct rt_sigframe *) 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(&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 *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 *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(0, &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;
 }

 extern void setup_rt_frame_n32(struct k_sigaction * ka,
 	struct pt_regs *regs, int signr, sigset_t *set, siginfo_t *info);

 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);
 	}
 }
	/*
	* 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 *frame;
	sigset_t blocked;

	frame = (struct sigframe *) 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 ...
	*/
	if (current_thread_info()->flags & TIF_SYSCALL_TRACE)
	do_syscall_trace(&regs, 1);
	__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 *frame;
	sigset_t set;
	stack_t st;

	frame = (struct rt_sigframe *) 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(&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 *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 *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(0, &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;
	}

	extern void setup_rt_frame_n32(struct k_sigaction * ka,
	struct pt_regs regs, int signr, sigset_t set, siginfo_t *info);

	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);
	}
	}