[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
save_static_function(sys_sigsuspend);
__attribute_used__ noinline static 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

save_static_function(sys_rt_sigsuspend);
__attribute_used__ noinline static 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
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;

	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
	204	save_static_function(sys_sigsuspend);
	205	__attribute_used__ noinline static int
	206	_sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
	207	{
7b3e2fc8	208	sigset_t newset;
fe00f943	209	sigset_t __user *uset;
1da177e4	210
fe00f943	211	uset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	212	if (copy_from_user(&newset, uset, sizeof(sigset_t)))
	213	return -EFAULT;
	214	sigdelsetmask(&newset, ~_BLOCKABLE);
	215
	216	spin_lock_irq(&current->sighand->siglock);
7b3e2fc8	217	current->saved_sigmask = current->blocked;
1da177e4 LT	218	current->blocked = newset;
	219	recalc_sigpending();
	220	spin_unlock_irq(&current->sighand->siglock);
	221
7b3e2fc8 RB	222	current->state = TASK_INTERRUPTIBLE;
	223	schedule();
	224	set_thread_flag(TIF_RESTORE_SIGMASK);
	225	return -ERESTARTNOHAND;
1da177e4 LT	226	}
	227	#endif
	228
	229	save_static_function(sys_rt_sigsuspend);
	230	__attribute_used__ noinline static int
	231	_sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
	232	{
7b3e2fc8	233	sigset_t newset;
fe00f943	234	sigset_t __user *unewset;
1da177e4 LT	235	size_t sigsetsize;
	236
	237	/* XXX Don't preclude handling different sized sigset_t's. */
	238	sigsetsize = regs.regs[5];
	239	if (sigsetsize != sizeof(sigset_t))
	240	return -EINVAL;
	241
fe00f943	242	unewset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	243	if (copy_from_user(&newset, unewset, sizeof(newset)))
	244	return -EFAULT;
	245	sigdelsetmask(&newset, ~_BLOCKABLE);
	246
	247	spin_lock_irq(&current->sighand->siglock);
7b3e2fc8	248	current->saved_sigmask = current->blocked;
1da177e4	249	current->blocked = newset;
e0daad44	250	recalc_sigpending();
1da177e4 LT	251	spin_unlock_irq(&current->sighand->siglock);
1da177e4 LT	252
7b3e2fc8 RB	253	current->state = TASK_INTERRUPTIBLE;
	254	schedule();
	255	set_thread_flag(TIF_RESTORE_SIGMASK);
	256	return -ERESTARTNOHAND;
1da177e4 LT	257	}
	258
	259	#ifdef CONFIG_TRAD_SIGNALS
9c6031cc AN	260	asmlinkage int sys_sigaction(int sig, const struct sigaction __user *act,
9c6031cc AN	261	struct sigaction __user *oact)
1da177e4 LT	262	{
	263	struct k_sigaction new_ka, old_ka;
	264	int ret;
	265	int err = 0;
	266
	267	if (act) {
	268	old_sigset_t mask;
	269
	270	if (!access_ok(VERIFY_READ, act, sizeof(*act)))
	271	return -EFAULT;
	272	err \|= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
	273	err \|= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
	274	err \|= __get_user(mask, &act->sa_mask.sig[0]);
	275	if (err)
	276	return -EFAULT;
	277
	278	siginitset(&new_ka.sa.sa_mask, mask);
	279	}
	280
	281	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	282
	283	if (!ret && oact) {
	284	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
e0daad44	285	return -EFAULT;
1da177e4 LT	286	err \|= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	287	err \|= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
	288	err \|= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
	289	err \|= __put_user(0, &oact->sa_mask.sig[1]);
	290	err \|= __put_user(0, &oact->sa_mask.sig[2]);
	291	err \|= __put_user(0, &oact->sa_mask.sig[3]);
	292	if (err)
	293	return -EFAULT;
	294	}
	295
	296	return ret;
	297	}
	298	#endif
	299
	300	asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
	301	{
fe00f943 RB	302	const stack_t __user uss = (const stack_t __user ) regs.regs[4];
fe00f943 RB	303	stack_t __user uoss = (stack_t __user ) regs.regs[5];
1da177e4 LT	304	unsigned long usp = regs.regs[29];
	305
	306	return do_sigaltstack(uss, uoss, usp);
	307	}
	308
1da177e4 LT	309	#ifdef CONFIG_TRAD_SIGNALS
	310	save_static_function(sys_sigreturn);
	311	__attribute_used__ noinline static void
	312	_sys_sigreturn(nabi_no_regargs struct pt_regs regs)
	313	{
9bbf28a3	314	struct sigframe __user *frame;
1da177e4 LT	315	sigset_t blocked;
1da177e4 LT	316
9bbf28a3	317	frame = (struct sigframe __user *) regs.regs[29];
1da177e4 LT	318	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	319	goto badframe;
	320	if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
	321	goto badframe;
	322
	323	sigdelsetmask(&blocked, ~_BLOCKABLE);
	324	spin_lock_irq(&current->sighand->siglock);
	325	current->blocked = blocked;
	326	recalc_sigpending();
	327	spin_unlock_irq(&current->sighand->siglock);
	328
	329	if (restore_sigcontext(&regs, &frame->sf_sc))
	330	goto badframe;
	331
	332	/*
	333	* Don't let your children do this ...
	334	*/
1da177e4 LT	335	__asm__ __volatile__(
	336	"move\t$29, %0\n\t"
	337	"j\tsyscall_exit"
	338	:/* no outputs */
	339	:"r" (&regs));
	340	/* Unreached */
	341
	342	badframe:
	343	force_sig(SIGSEGV, current);
	344	}
e50c0a8f	345	#endif /* CONFIG_TRAD_SIGNALS */
1da177e4 LT	346
	347	save_static_function(sys_rt_sigreturn);
	348	__attribute_used__ noinline static void
	349	_sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
	350	{
9bbf28a3	351	struct rt_sigframe __user *frame;
1da177e4 LT	352	sigset_t set;
	353	stack_t st;
	354
9bbf28a3	355	frame = (struct rt_sigframe __user *) regs.regs[29];
1da177e4 LT	356	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	357	goto badframe;
	358	if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
	359	goto badframe;
	360
	361	sigdelsetmask(&set, ~_BLOCKABLE);
	362	spin_lock_irq(&current->sighand->siglock);
	363	current->blocked = set;
	364	recalc_sigpending();
	365	spin_unlock_irq(&current->sighand->siglock);
	366
	367	if (restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext))
	368	goto badframe;
	369
	370	if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
	371	goto badframe;
	372	/* It is more difficult to avoid calling this function than to
	373	call it and ignore errors. */
9bbf28a3	374	do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
1da177e4 LT	375
	376	/*
	377	* Don't let your children do this ...
	378	*/
	379	__asm__ __volatile__(
	380	"move\t$29, %0\n\t"
	381	"j\tsyscall_exit"
	382	:/* no outputs */
	383	:"r" (&regs));
	384	/* Unreached */
	385
	386	badframe:
	387	force_sig(SIGSEGV, current);
	388	}
	389
	390	#ifdef CONFIG_TRAD_SIGNALS
129bc8f7	391	int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
1da177e4 LT	392	int signr, sigset_t *set)
1da177e4 LT	393	{
9bbf28a3	394	struct sigframe __user *frame;
1da177e4 LT	395	int err = 0;
	396
	397	frame = get_sigframe(ka, regs, sizeof(*frame));
	398	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	399	goto give_sigsegv;
	400
601dde45	401	err \|= install_sigtramp(frame->sf_code, __NR_sigreturn);
1da177e4 LT	402
	403	err \|= setup_sigcontext(regs, &frame->sf_sc);
	404	err \|= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
	405	if (err)
	406	goto give_sigsegv;
	407
	408	/*
	409	* Arguments to signal handler:
	410	*
	411	* a0 = signal number
	412	* a1 = 0 (should be cause)
	413	* a2 = pointer to struct sigcontext
	414	*
	415	* $25 and c0_epc point to the signal handler, $29 points to the
	416	* struct sigframe.
	417	*/
	418	regs->regs[ 4] = signr;
	419	regs->regs[ 5] = 0;
	420	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
	421	regs->regs[29] = (unsigned long) frame;
	422	regs->regs[31] = (unsigned long) frame->sf_code;
	423	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
	424
722bb63d	425	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4	426	current->comm, current->pid,
722bb63d	427	frame, regs->cp0_epc, regs->regs[31]);
e0daad44	428	return 0;
1da177e4 LT	429
	430	give_sigsegv:
	431	force_sigsegv(signr, current);
7b3e2fc8	432	return -EFAULT;
1da177e4 LT	433	}
	434	#endif
	435
129bc8f7	436	int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
1da177e4 LT	437	int signr, sigset_t set, siginfo_t info)
1da177e4 LT	438	{
9bbf28a3	439	struct rt_sigframe __user *frame;
1da177e4 LT	440	int err = 0;
	441
	442	frame = get_sigframe(ka, regs, sizeof(*frame));
	443	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	444	goto give_sigsegv;
	445
601dde45	446	err \|= install_sigtramp(frame->rs_code, __NR_rt_sigreturn);
1da177e4 LT	447
	448	/* Create siginfo. */
	449	err \|= copy_siginfo_to_user(&frame->rs_info, info);
	450
	451	/* Create the ucontext. */
	452	err \|= __put_user(0, &frame->rs_uc.uc_flags);
5665a0ac	453	err \|= __put_user(NULL, &frame->rs_uc.uc_link);
9c6031cc	454	err \|= __put_user((void __user *)current->sas_ss_sp,
1da177e4 LT	455	&frame->rs_uc.uc_stack.ss_sp);
	456	err \|= __put_user(sas_ss_flags(regs->regs[29]),
	457	&frame->rs_uc.uc_stack.ss_flags);
	458	err \|= __put_user(current->sas_ss_size,
	459	&frame->rs_uc.uc_stack.ss_size);
	460	err \|= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	461	err \|= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
	462
	463	if (err)
	464	goto give_sigsegv;
	465
	466	/*
	467	* Arguments to signal handler:
	468	*
	469	* a0 = signal number
	470	* a1 = 0 (should be cause)
	471	* a2 = pointer to ucontext
	472	*
	473	* $25 and c0_epc point to the signal handler, $29 points to
	474	* the struct rt_sigframe.
	475	*/
	476	regs->regs[ 4] = signr;
	477	regs->regs[ 5] = (unsigned long) &frame->rs_info;
	478	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
	479	regs->regs[29] = (unsigned long) frame;
	480	regs->regs[31] = (unsigned long) frame->rs_code;
	481	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
	482
722bb63d	483	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4 LT	484	current->comm, current->pid,
1da177e4 LT	485	frame, regs->cp0_epc, regs->regs[31]);
722bb63d	486
7b3e2fc8	487	return 0;
1da177e4 LT	488
	489	give_sigsegv:
	490	force_sigsegv(signr, current);
7b3e2fc8	491	return -EFAULT;
1da177e4 LT	492	}
1da177e4 LT	493
129bc8f7	494	static inline int handle_signal(unsigned long sig, siginfo_t *info,
1da177e4 LT	495	struct k_sigaction ka, sigset_t oldset, struct pt_regs *regs)
1da177e4 LT	496	{
129bc8f7 RB	497	int ret;
129bc8f7 RB	498
1da177e4 LT	499	switch(regs->regs[0]) {
	500	case ERESTART_RESTARTBLOCK:
	501	case ERESTARTNOHAND:
	502	regs->regs[2] = EINTR;
	503	break;
	504	case ERESTARTSYS:
7b3e2fc8	505	if (!(ka->sa.sa_flags & SA_RESTART)) {
1da177e4 LT	506	regs->regs[2] = EINTR;
	507	break;
	508	}
	509	/* fallthrough */
	510	case ERESTARTNOINTR: /* Userland will reload $v0. */
	511	regs->regs[7] = regs->regs[26];
	512	regs->cp0_epc -= 8;
	513	}
	514
	515	regs->regs[0] = 0; /* Don't deal with this again. */
	516
e50c0a8f	517	if (sig_uses_siginfo(ka))
129bc8f7	518	ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
1da177e4	519	else
129bc8f7	520	ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);
1da177e4	521
69be8f18 SR	522	spin_lock_irq(&current->sighand->siglock);
	523	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
	524	if (!(ka->sa.sa_flags & SA_NODEFER))
1da177e4	525	sigaddset(&current->blocked,sig);
69be8f18 SR	526	recalc_sigpending();
69be8f18 SR	527	spin_unlock_irq(&current->sighand->siglock);
129bc8f7 RB	528
129bc8f7 RB	529	return ret;
1da177e4 LT	530	}
1da177e4 LT	531
40ac5d47	532	void do_signal(struct pt_regs *regs)
1da177e4 LT	533	{
1da177e4 LT	534	struct k_sigaction ka;
7b3e2fc8	535	sigset_t *oldset;
1da177e4 LT	536	siginfo_t info;
	537	int signr;
	538
1da177e4 LT	539	/*
	540	* We want the common case to go fast, which is why we may in certain
	541	* cases get here from kernel mode. Just return without doing anything
	542	* if so.
	543	*/
	544	if (!user_mode(regs))
40ac5d47	545	return;
1da177e4	546
7b3e2fc8 RB	547	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	548	oldset = &current->saved_sigmask;
	549	else
1da177e4 LT	550	oldset = &current->blocked;
	551
	552	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
7b3e2fc8 RB	553	if (signr > 0) {
	554	/* Whee! Actually deliver the signal. */
	555	if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
	556	/*
	557	* A signal was successfully delivered; the saved
	558	* sigmask will have been stored in the signal frame,
	559	* and will be restored by sigreturn, so we can simply
	560	* clear the TIF_RESTORE_SIGMASK flag.
	561	*/
	562	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	563	clear_thread_flag(TIF_RESTORE_SIGMASK);
	564	}
45887e12 RB	565
45887e12 RB	566	return;
7b3e2fc8	567	}
1da177e4	568
1da177e4 LT	569	/*
	570	* Who's code doesn't conform to the restartable syscall convention
	571	* dies here!!! The li instruction, a single machine instruction,
	572	* must directly be followed by the syscall instruction.
	573	*/
	574	if (regs->regs[0]) {
	575	if (regs->regs[2] == ERESTARTNOHAND \|\|
	576	regs->regs[2] == ERESTARTSYS \|\|
	577	regs->regs[2] == ERESTARTNOINTR) {
	578	regs->regs[7] = regs->regs[26];
	579	regs->cp0_epc -= 8;
	580	}
	581	if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
	582	regs->regs[2] = __NR_restart_syscall;
	583	regs->regs[7] = regs->regs[26];
	584	regs->cp0_epc -= 4;
	585	}
13fdd31a	586	regs->regs[0] = 0; /* Don't deal with this again. */
1da177e4	587	}
7b3e2fc8 RB	588
	589	/*
	590	* If there's no signal to deliver, we just put the saved sigmask
	591	* back
	592	*/
	593	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
	594	clear_thread_flag(TIF_RESTORE_SIGMASK);
	595	sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	596	}
1da177e4 LT	597	}
	598
	599	/*
	600	* notification of userspace execution resumption
7b3e2fc8	601	* - triggered by the TIF_WORK_MASK flags
1da177e4	602	*/
7b3e2fc8	603	asmlinkage void do_notify_resume(struct pt_regs regs, void unused,
1da177e4 LT	604	__u32 thread_info_flags)
	605	{
	606	/* deal with pending signal delivery */
7b3e2fc8 RB	607	if (thread_info_flags & (_TIF_SIGPENDING \| _TIF_RESTORE_SIGMASK))
7b3e2fc8 RB	608	current->thread.abi->do_signal(regs);
1da177e4	609	}