[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/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 _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

#if ICACHE_REFILLS_WORKAROUND_WAR == 0

struct rt_sigframe {
	u32 rs_ass[4];		/* argument save space for o32 */
	u32 rs_code[2];		/* signal trampoline */
	struct siginfo rs_info;
	struct ucontext rs_uc;
};

#else

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

#endif

/*
 * Helper routines
 */
int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
	int err = 0;
	int i;

	err |= __put_user(regs->cp0_epc, &sc->sc_pc);

	err |= __put_user(0, &sc->sc_regs[0]);
	for (i = 1; i < 32; i++)
		err |= __put_user(regs->regs[i], &sc->sc_regs[i]);

	err |= __put_user(regs->hi, &sc->sc_mdhi);
	err |= __put_user(regs->lo, &sc->sc_mdlo);
	if (cpu_has_dsp) {
		err |= __put_user(mfhi1(), &sc->sc_hi1);
		err |= __put_user(mflo1(), &sc->sc_lo1);
		err |= __put_user(mfhi2(), &sc->sc_hi2);
		err |= __put_user(mflo2(), &sc->sc_lo2);
		err |= __put_user(mfhi3(), &sc->sc_hi3);
		err |= __put_user(mflo3(), &sc->sc_lo3);
		err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
	}

	err |= __put_user(!!used_math(), &sc->sc_used_math);

	if (used_math()) {
		/*
		 * Save FPU state to signal context. Signal handler
		 * will "inherit" current FPU state.
		 */
		preempt_disable();

		if (!is_fpu_owner()) {
			own_fpu();
			restore_fp(current);
		}
		err |= save_fp_context(sc);

		preempt_enable();
	}
	return err;
}

int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
	unsigned int used_math;
	unsigned long treg;
	int err = 0;
	int i;

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

	err |= __get_user(regs->cp0_epc, &sc->sc_pc);
	err |= __get_user(regs->hi, &sc->sc_mdhi);
	err |= __get_user(regs->lo, &sc->sc_mdlo);
	if (cpu_has_dsp) {
		err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
		err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
		err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
		err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
		err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
		err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
		err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
	}

	for (i = 1; i < 32; i++)
		err |= __get_user(regs->regs[i], &sc->sc_regs[i]);

	err |= __get_user(used_math, &sc->sc_used_math);
	conditional_used_math(used_math);

	preempt_disable();

	if (used_math()) {
		/* restore fpu context if we have used it before */
		own_fpu();
		err |= restore_fp_context(sc);
	} else {
		/* signal handler may have used FPU.  Give it up. */
		lose_fpu();
	}

	preempt_enable();

	return err;
}

void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
			  size_t frame_size)
{
	unsigned long sp;

	/* Default to using normal stack */
	sp = regs->regs[29];

	/*
	 * FPU emulator may have it's own trampoline active just
	 * above the user stack, 16-bytes before the next lowest
	 * 16 byte boundary.  Try to avoid trashing it.
	 */
	sp -= 32;

	/* This is the X/Open sanctioned signal stack switching.  */
	if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
		sp = current->sas_ss_sp + current->sas_ss_size;

	return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
}

int install_sigtramp(unsigned int __user *tramp, unsigned int syscall)
{
	int err;

	/*
	 * Set up the return code ...
	 *
	 *         li      v0, __NR__foo_sigreturn
	 *         syscall
	 */

	err = __put_user(0x24020000 + syscall, tramp + 0);
	err |= __put_user(0x0000000c         , tramp + 1);
	if (ICACHE_REFILLS_WORKAROUND_WAR) {
		err |= __put_user(0, tramp + 2);
		err |= __put_user(0, tramp + 3);
		err |= __put_user(0, tramp + 4);
		err |= __put_user(0, tramp + 5);
		err |= __put_user(0, tramp + 6);
		err |= __put_user(0, tramp + 7);
	}
	flush_cache_sigtramp((unsigned long) tramp);

	return err;
}

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

#ifdef CONFIG_TRAD_SIGNALS
asmlinkage int sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
{
	sigset_t 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);
	current->saved_sigmask = current->blocked;
	current->blocked = newset;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

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

asmlinkage int sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
{
	sigset_t 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);
	current->saved_sigmask = current->blocked;
	current->blocked = newset;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

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

#ifdef CONFIG_TRAD_SIGNALS
asmlinkage int sys_sigaction(int sig, const struct sigaction __user *act,
	struct sigaction __user *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);
}

#ifdef CONFIG_TRAD_SIGNALS
asmlinkage 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 */

asmlinkage 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;

	err |= 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;

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

give_sigsegv:
	force_sigsegv(signr, current);
	return -EFAULT;
}
#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;

	err |= 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 __user *)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;

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

	return 0;

give_sigsegv:
	force_sigsegv(signr, current);
	return -EFAULT;
}

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;
}

void do_signal(struct pt_regs *regs)
{
	struct k_sigaction ka;
	sigset_t *oldset;
	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;

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

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	if (signr > 0) {
		/* Whee!  Actually deliver the signal.  */
		if (handle_signal(signr, &info, &ka, oldset, regs) == 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;
	}

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

	/*
	 * 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);
	}
}

/*
 * notification of userspace execution resumption
 * - triggered by the TIF_WORK_MASK flags
 */
asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
	__u32 thread_info_flags)
{
	/* deal with pending signal delivery */
	if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
		current->thread.abi->do_signal(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	*/
02416dcf	10	#include <linux/cache.h>
1da177e4 LT	11	#include <linux/sched.h>
	12	#include <linux/mm.h>
	13	#include <linux/personality.h>
	14	#include <linux/smp.h>
	15	#include <linux/smp_lock.h>
	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/compiler.h>
	23
e50c0a8f	24	#include <asm/abi.h>
1da177e4 LT	25	#include <asm/asm.h>
	26	#include <linux/bitops.h>
	27	#include <asm/cacheflush.h>
	28	#include <asm/fpu.h>
	29	#include <asm/sim.h>
	30	#include <asm/uaccess.h>
	31	#include <asm/ucontext.h>
	32	#include <asm/cpu-features.h>
02416dcf	33	#include <asm/war.h>
1da177e4 LT	34
	35	#include "signal-common.h"
	36
1da177e4 LT	37	#define _BLOCKABLE (~(sigmask(SIGKILL) \| sigmask(SIGSTOP)))
1da177e4 LT	38
c0b9bae9 FBH	39	#if ICACHE_REFILLS_WORKAROUND_WAR == 0
	40
	41	struct rt_sigframe {
	42	u32 rs_ass[4]; /* argument save space for o32 */
	43	u32 rs_code[2]; /* signal trampoline */
	44	struct siginfo rs_info;
	45	struct ucontext rs_uc;
	46	};
	47
	48	#else
	49
	50	struct rt_sigframe {
	51	u32 rs_ass[4]; /* argument save space for o32 */
	52	u32 rs_pad[2];
	53	struct siginfo rs_info;
	54	struct ucontext rs_uc;
	55	u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */
	56	};
	57
	58	#endif
	59
c3fc4ab3 FBH	60	/*
	61	* Helper routines
	62	*/
	63	int setup_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
	64	{
	65	int err = 0;
	66	int i;
	67
	68	err \|= __put_user(regs->cp0_epc, &sc->sc_pc);
	69
	70	err \|= __put_user(0, &sc->sc_regs[0]);
	71	for (i = 1; i < 32; i++)
	72	err \|= __put_user(regs->regs[i], &sc->sc_regs[i]);
	73
	74	err \|= __put_user(regs->hi, &sc->sc_mdhi);
	75	err \|= __put_user(regs->lo, &sc->sc_mdlo);
	76	if (cpu_has_dsp) {
	77	err \|= __put_user(mfhi1(), &sc->sc_hi1);
	78	err \|= __put_user(mflo1(), &sc->sc_lo1);
	79	err \|= __put_user(mfhi2(), &sc->sc_hi2);
	80	err \|= __put_user(mflo2(), &sc->sc_lo2);
	81	err \|= __put_user(mfhi3(), &sc->sc_hi3);
	82	err \|= __put_user(mflo3(), &sc->sc_lo3);
	83	err \|= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
	84	}
	85
	86	err \|= __put_user(!!used_math(), &sc->sc_used_math);
	87
	88	if (used_math()) {
	89	/*
	90	* Save FPU state to signal context. Signal handler
	91	* will "inherit" current FPU state.
	92	*/
	93	preempt_disable();
	94
	95	if (!is_fpu_owner()) {
	96	own_fpu();
	97	restore_fp(current);
	98	}
	99	err \|= save_fp_context(sc);
	100
	101	preempt_enable();
	102	}
	103	return err;
	104	}
	105
	106	int restore_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
	107	{
	108	unsigned int used_math;
	109	unsigned long treg;
	110	int err = 0;
	111	int i;
	112
	113	/* Always make any pending restarted system calls return -EINTR */
	114	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	115
	116	err \|= __get_user(regs->cp0_epc, &sc->sc_pc);
	117	err \|= __get_user(regs->hi, &sc->sc_mdhi);
	118	err \|= __get_user(regs->lo, &sc->sc_mdlo);
	119	if (cpu_has_dsp) {
	120	err \|= __get_user(treg, &sc->sc_hi1); mthi1(treg);
	121	err \|= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
	122	err \|= __get_user(treg, &sc->sc_hi2); mthi2(treg);
	123	err \|= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
124	err \|= __get_user(treg, &sc->sc_hi3); mthi3(treg);
125	err \|= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
126	err \|= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
127	}
128
129	for (i = 1; i < 32; i++)
130	err \|= __get_user(regs->regs[i], &sc->sc_regs[i]);
131
132	err \|= __get_user(used_math, &sc->sc_used_math);
133	conditional_used_math(used_math);
134
135	preempt_disable();
136
137	if (used_math()) {
138	/* restore fpu context if we have used it before */
139	own_fpu();
140	err \|= restore_fp_context(sc);
141	} else {
142	/* signal handler may have used FPU. Give it up. */
143	lose_fpu();
144	}
145
146	preempt_enable();
147
148	return err;
149	}
150
151	void __user get_sigframe(struct k_sigaction ka, struct pt_regs *regs,
152	size_t frame_size)
153	{
154	unsigned long sp;
155
156	/* Default to using normal stack */
157	sp = regs->regs[29];
158
159	/*
160	* FPU emulator may have it's own trampoline active just
161	* above the user stack, 16-bytes before the next lowest
162	* 16 byte boundary. Try to avoid trashing it.
163	*/
164	sp -= 32;
165
166	/* This is the X/Open sanctioned signal stack switching. */
167	if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
168	sp = current->sas_ss_sp + current->sas_ss_size;
169
170	return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
171	}
172
173	int install_sigtramp(unsigned int __user *tramp, unsigned int syscall)
174	{
175	int err;
176
177	/*
178	* Set up the return code ...
179	*
180	* li v0, __NR__foo_sigreturn
181	* syscall
182	*/
183
184	err = __put_user(0x24020000 + syscall, tramp + 0);
601dde45	185	err \|= __put_user(0x0000000c , tramp + 1);
c3fc4ab3 FBH	186	if (ICACHE_REFILLS_WORKAROUND_WAR) {
	187	err \|= __put_user(0, tramp + 2);
	188	err \|= __put_user(0, tramp + 3);
	189	err \|= __put_user(0, tramp + 4);
	190	err \|= __put_user(0, tramp + 5);
	191	err \|= __put_user(0, tramp + 6);
	192	err \|= __put_user(0, tramp + 7);
	193	}
	194	flush_cache_sigtramp((unsigned long) tramp);
	195
	196	return err;
	197	}
	198
1da177e4 LT	199	/*
	200	* Atomically swap in the new signal mask, and wait for a signal.
	201	*/
	202
	203	#ifdef CONFIG_TRAD_SIGNALS
f90080a0	204	asmlinkage int sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
1da177e4	205	{
7b3e2fc8	206	sigset_t newset;
fe00f943	207	sigset_t __user *uset;
1da177e4	208
fe00f943	209	uset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	210	if (copy_from_user(&newset, uset, sizeof(sigset_t)))
	211	return -EFAULT;
	212	sigdelsetmask(&newset, ~_BLOCKABLE);
	213
	214	spin_lock_irq(&current->sighand->siglock);
7b3e2fc8	215	current->saved_sigmask = current->blocked;
1da177e4 LT	216	current->blocked = newset;
	217	recalc_sigpending();
	218	spin_unlock_irq(&current->sighand->siglock);
	219
7b3e2fc8 RB	220	current->state = TASK_INTERRUPTIBLE;
	221	schedule();
	222	set_thread_flag(TIF_RESTORE_SIGMASK);
	223	return -ERESTARTNOHAND;
1da177e4 LT	224	}
	225	#endif
	226
f90080a0	227	asmlinkage int sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
1da177e4	228	{
7b3e2fc8	229	sigset_t newset;
fe00f943	230	sigset_t __user *unewset;
1da177e4 LT	231	size_t sigsetsize;
	232
	233	/* XXX Don't preclude handling different sized sigset_t's. */
	234	sigsetsize = regs.regs[5];
	235	if (sigsetsize != sizeof(sigset_t))
	236	return -EINVAL;
	237
fe00f943	238	unewset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	239	if (copy_from_user(&newset, unewset, sizeof(newset)))
	240	return -EFAULT;
	241	sigdelsetmask(&newset, ~_BLOCKABLE);
	242
	243	spin_lock_irq(&current->sighand->siglock);
7b3e2fc8	244	current->saved_sigmask = current->blocked;
1da177e4	245	current->blocked = newset;
e0daad44	246	recalc_sigpending();
1da177e4 LT	247	spin_unlock_irq(&current->sighand->siglock);
1da177e4 LT	248
7b3e2fc8 RB	249	current->state = TASK_INTERRUPTIBLE;
	250	schedule();
	251	set_thread_flag(TIF_RESTORE_SIGMASK);
	252	return -ERESTARTNOHAND;
1da177e4 LT	253	}
	254
	255	#ifdef CONFIG_TRAD_SIGNALS
9c6031cc AN	256	asmlinkage int sys_sigaction(int sig, const struct sigaction __user *act,
9c6031cc AN	257	struct sigaction __user *oact)
1da177e4 LT	258	{
	259	struct k_sigaction new_ka, old_ka;
	260	int ret;
	261	int err = 0;
	262
	263	if (act) {
	264	old_sigset_t mask;
	265
	266	if (!access_ok(VERIFY_READ, act, sizeof(*act)))
	267	return -EFAULT;
	268	err \|= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
	269	err \|= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
	270	err \|= __get_user(mask, &act->sa_mask.sig[0]);
	271	if (err)
	272	return -EFAULT;
	273
	274	siginitset(&new_ka.sa.sa_mask, mask);
	275	}
	276
	277	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	278
	279	if (!ret && oact) {
	280	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
e0daad44	281	return -EFAULT;
1da177e4 LT	282	err \|= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	283	err \|= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
	284	err \|= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
	285	err \|= __put_user(0, &oact->sa_mask.sig[1]);
	286	err \|= __put_user(0, &oact->sa_mask.sig[2]);
	287	err \|= __put_user(0, &oact->sa_mask.sig[3]);
	288	if (err)
	289	return -EFAULT;
	290	}
	291
	292	return ret;
	293	}
	294	#endif
	295
	296	asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
	297	{
fe00f943 RB	298	const stack_t __user uss = (const stack_t __user ) regs.regs[4];
fe00f943 RB	299	stack_t __user uoss = (stack_t __user ) regs.regs[5];
1da177e4 LT	300	unsigned long usp = regs.regs[29];
	301
	302	return do_sigaltstack(uss, uoss, usp);
	303	}
	304
1da177e4	305	#ifdef CONFIG_TRAD_SIGNALS
f90080a0	306	asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
1da177e4	307	{
9bbf28a3	308	struct sigframe __user *frame;
1da177e4 LT	309	sigset_t blocked;
1da177e4 LT	310
9bbf28a3	311	frame = (struct sigframe __user *) regs.regs[29];
1da177e4 LT	312	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	313	goto badframe;
	314	if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
	315	goto badframe;
	316
	317	sigdelsetmask(&blocked, ~_BLOCKABLE);
	318	spin_lock_irq(&current->sighand->siglock);
	319	current->blocked = blocked;
	320	recalc_sigpending();
	321	spin_unlock_irq(&current->sighand->siglock);
	322
	323	if (restore_sigcontext(&regs, &frame->sf_sc))
	324	goto badframe;
	325
	326	/*
	327	* Don't let your children do this ...
	328	*/
1da177e4 LT	329	__asm__ __volatile__(
	330	"move\t$29, %0\n\t"
	331	"j\tsyscall_exit"
	332	:/* no outputs */
	333	:"r" (&regs));
	334	/* Unreached */
	335
	336	badframe:
	337	force_sig(SIGSEGV, current);
	338	}
e50c0a8f	339	#endif /* CONFIG_TRAD_SIGNALS */
1da177e4	340
f90080a0	341	asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
1da177e4	342	{
9bbf28a3	343	struct rt_sigframe __user *frame;
1da177e4 LT	344	sigset_t set;
	345	stack_t st;
	346
9bbf28a3	347	frame = (struct rt_sigframe __user *) regs.regs[29];
1da177e4 LT	348	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	349	goto badframe;
	350	if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
	351	goto badframe;
	352
	353	sigdelsetmask(&set, ~_BLOCKABLE);
	354	spin_lock_irq(&current->sighand->siglock);
	355	current->blocked = set;
	356	recalc_sigpending();
	357	spin_unlock_irq(&current->sighand->siglock);
	358
	359	if (restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext))
	360	goto badframe;
	361
	362	if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
	363	goto badframe;
	364	/* It is more difficult to avoid calling this function than to
	365	call it and ignore errors. */
9bbf28a3	366	do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
1da177e4 LT	367
	368	/*
	369	* Don't let your children do this ...
	370	*/
	371	__asm__ __volatile__(
	372	"move\t$29, %0\n\t"
	373	"j\tsyscall_exit"
	374	:/* no outputs */
	375	:"r" (&regs));
	376	/* Unreached */
	377
	378	badframe:
	379	force_sig(SIGSEGV, current);
	380	}
	381
	382	#ifdef CONFIG_TRAD_SIGNALS
129bc8f7	383	int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
1da177e4 LT	384	int signr, sigset_t *set)
1da177e4 LT	385	{
9bbf28a3	386	struct sigframe __user *frame;
1da177e4 LT	387	int err = 0;
	388
	389	frame = get_sigframe(ka, regs, sizeof(*frame));
	390	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	391	goto give_sigsegv;
	392
601dde45	393	err \|= install_sigtramp(frame->sf_code, __NR_sigreturn);
1da177e4 LT	394
	395	err \|= setup_sigcontext(regs, &frame->sf_sc);
	396	err \|= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
	397	if (err)
	398	goto give_sigsegv;
	399
	400	/*
	401	* Arguments to signal handler:
	402	*
	403	* a0 = signal number
	404	* a1 = 0 (should be cause)
	405	* a2 = pointer to struct sigcontext
	406	*
	407	* $25 and c0_epc point to the signal handler, $29 points to the
	408	* struct sigframe.
	409	*/
	410	regs->regs[ 4] = signr;
	411	regs->regs[ 5] = 0;
	412	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
	413	regs->regs[29] = (unsigned long) frame;
	414	regs->regs[31] = (unsigned long) frame->sf_code;
	415	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
	416
722bb63d	417	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4	418	current->comm, current->pid,
722bb63d	419	frame, regs->cp0_epc, regs->regs[31]);
e0daad44	420	return 0;
1da177e4 LT	421
	422	give_sigsegv:
	423	force_sigsegv(signr, current);
7b3e2fc8	424	return -EFAULT;
1da177e4 LT	425	}
	426	#endif
	427
129bc8f7	428	int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
1da177e4 LT	429	int signr, sigset_t set, siginfo_t info)
1da177e4 LT	430	{
9bbf28a3	431	struct rt_sigframe __user *frame;
1da177e4 LT	432	int err = 0;
	433
	434	frame = get_sigframe(ka, regs, sizeof(*frame));
	435	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	436	goto give_sigsegv;
	437
601dde45	438	err \|= install_sigtramp(frame->rs_code, __NR_rt_sigreturn);
1da177e4 LT	439
	440	/* Create siginfo. */
	441	err \|= copy_siginfo_to_user(&frame->rs_info, info);
	442
	443	/* Create the ucontext. */
	444	err \|= __put_user(0, &frame->rs_uc.uc_flags);
5665a0ac	445	err \|= __put_user(NULL, &frame->rs_uc.uc_link);
9c6031cc	446	err \|= __put_user((void __user *)current->sas_ss_sp,
1da177e4 LT	447	&frame->rs_uc.uc_stack.ss_sp);
	448	err \|= __put_user(sas_ss_flags(regs->regs[29]),
	449	&frame->rs_uc.uc_stack.ss_flags);
	450	err \|= __put_user(current->sas_ss_size,
	451	&frame->rs_uc.uc_stack.ss_size);
	452	err \|= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	453	err \|= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
	454
	455	if (err)
	456	goto give_sigsegv;
	457
	458	/*
	459	* Arguments to signal handler:
	460	*
	461	* a0 = signal number
	462	* a1 = 0 (should be cause)
	463	* a2 = pointer to ucontext
	464	*
	465	* $25 and c0_epc point to the signal handler, $29 points to
	466	* the struct rt_sigframe.
	467	*/
	468	regs->regs[ 4] = signr;
	469	regs->regs[ 5] = (unsigned long) &frame->rs_info;
	470	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
	471	regs->regs[29] = (unsigned long) frame;
	472	regs->regs[31] = (unsigned long) frame->rs_code;
	473	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
	474
722bb63d	475	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4 LT	476	current->comm, current->pid,
1da177e4 LT	477	frame, regs->cp0_epc, regs->regs[31]);
722bb63d	478
7b3e2fc8	479	return 0;
1da177e4 LT	480
	481	give_sigsegv:
	482	force_sigsegv(signr, current);
7b3e2fc8	483	return -EFAULT;
1da177e4 LT	484	}
1da177e4 LT	485
129bc8f7	486	static inline int handle_signal(unsigned long sig, siginfo_t *info,
1da177e4 LT	487	struct k_sigaction ka, sigset_t oldset, struct pt_regs *regs)
1da177e4 LT	488	{
129bc8f7 RB	489	int ret;
129bc8f7 RB	490
1da177e4 LT	491	switch(regs->regs[0]) {
	492	case ERESTART_RESTARTBLOCK:
	493	case ERESTARTNOHAND:
	494	regs->regs[2] = EINTR;
	495	break;
	496	case ERESTARTSYS:
7b3e2fc8	497	if (!(ka->sa.sa_flags & SA_RESTART)) {
1da177e4 LT	498	regs->regs[2] = EINTR;
	499	break;
	500	}
	501	/* fallthrough */
	502	case ERESTARTNOINTR: /* Userland will reload $v0. */
	503	regs->regs[7] = regs->regs[26];
	504	regs->cp0_epc -= 8;
	505	}
	506
	507	regs->regs[0] = 0; /* Don't deal with this again. */
	508
e50c0a8f	509	if (sig_uses_siginfo(ka))
129bc8f7	510	ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
1da177e4	511	else
129bc8f7	512	ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);
1da177e4	513
69be8f18 SR	514	spin_lock_irq(&current->sighand->siglock);
	515	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
	516	if (!(ka->sa.sa_flags & SA_NODEFER))
1da177e4	517	sigaddset(&current->blocked,sig);
69be8f18 SR	518	recalc_sigpending();
69be8f18 SR	519	spin_unlock_irq(&current->sighand->siglock);
129bc8f7 RB	520
129bc8f7 RB	521	return ret;
1da177e4 LT	522	}
1da177e4 LT	523
40ac5d47	524	void do_signal(struct pt_regs *regs)
1da177e4 LT	525	{
1da177e4 LT	526	struct k_sigaction ka;
7b3e2fc8	527	sigset_t *oldset;
1da177e4 LT	528	siginfo_t info;
	529	int signr;
	530
1da177e4 LT	531	/*
	532	* We want the common case to go fast, which is why we may in certain
	533	* cases get here from kernel mode. Just return without doing anything
	534	* if so.
	535	*/
	536	if (!user_mode(regs))
40ac5d47	537	return;
1da177e4	538
7b3e2fc8 RB	539	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	540	oldset = &current->saved_sigmask;
	541	else
1da177e4 LT	542	oldset = &current->blocked;
	543
	544	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
7b3e2fc8 RB	545	if (signr > 0) {
	546	/* Whee! Actually deliver the signal. */
	547	if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
	548	/*
	549	* A signal was successfully delivered; the saved
	550	* sigmask will have been stored in the signal frame,
	551	* and will be restored by sigreturn, so we can simply
	552	* clear the TIF_RESTORE_SIGMASK flag.
	553	*/
	554	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	555	clear_thread_flag(TIF_RESTORE_SIGMASK);
	556	}
45887e12 RB	557
45887e12 RB	558	return;
7b3e2fc8	559	}
1da177e4	560
1da177e4 LT	561	/*
	562	* Who's code doesn't conform to the restartable syscall convention
	563	* dies here!!! The li instruction, a single machine instruction,
	564	* must directly be followed by the syscall instruction.
	565	*/
	566	if (regs->regs[0]) {
	567	if (regs->regs[2] == ERESTARTNOHAND \|\|
	568	regs->regs[2] == ERESTARTSYS \|\|
	569	regs->regs[2] == ERESTARTNOINTR) {
	570	regs->regs[7] = regs->regs[26];
	571	regs->cp0_epc -= 8;
	572	}
	573	if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
	574	regs->regs[2] = __NR_restart_syscall;
	575	regs->regs[7] = regs->regs[26];
	576	regs->cp0_epc -= 4;
	577	}
13fdd31a	578	regs->regs[0] = 0; /* Don't deal with this again. */
1da177e4	579	}
7b3e2fc8 RB	580
	581	/*
	582	* If there's no signal to deliver, we just put the saved sigmask
	583	* back
	584	*/
	585	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
	586	clear_thread_flag(TIF_RESTORE_SIGMASK);
	587	sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	588	}
1da177e4 LT	589	}
	590
	591	/*
	592	* notification of userspace execution resumption
7b3e2fc8	593	* - triggered by the TIF_WORK_MASK flags
1da177e4	594	*/
7b3e2fc8	595	asmlinkage void do_notify_resume(struct pt_regs regs, void unused,
1da177e4 LT	596	__u32 thread_info_flags)
	597	{
	598	/* deal with pending signal delivery */
7b3e2fc8 RB	599	if (thread_info_flags & (_TIF_SIGPENDING \| _TIF_RESTORE_SIGMASK))
7b3e2fc8 RB	600	current->thread.abi->do_signal(regs);
1da177e4	601	}