[GitHub/mt8127/android_kernel_alcatel_ttab.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"

/*
 * 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.
 */
#if ICACHE_REFILLS_WORKAROUND_WAR == 0

struct sigframe {
	u32 sf_ass[4];		/* argument save space for o32 */
	u32 sf_code[2];		/* signal trampoline */
	struct sigcontext sf_sc;
	sigset_t sf_mask;
};

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 sigframe {
	u32 sf_ass[4];			/* argument save space for o32 */
	u32 sf_pad[2];
	struct sigcontext sf_sc;	/* hw context */
	sigset_t sf_mask;
	u32 sf_code[8] ____cacheline_aligned;	/* signal trampoline */
};

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 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
66680583 RB	37	/*
	38	* Horribly complicated - with the bloody RM9000 workarounds enabled
	39	* the signal trampolines is moving to the end of the structure so we can
	40	* increase the alignment without breaking software compatibility.
	41	*/
c0b9bae9 FBH	42	#if ICACHE_REFILLS_WORKAROUND_WAR == 0
c0b9bae9 FBH	43
66680583 RB	44	struct sigframe {
	45	u32 sf_ass[4]; /* argument save space for o32 */
	46	u32 sf_code[2]; /* signal trampoline */
	47	struct sigcontext sf_sc;
	48	sigset_t sf_mask;
	49	};
	50
c0b9bae9 FBH	51	struct rt_sigframe {
	52	u32 rs_ass[4]; /* argument save space for o32 */
	53	u32 rs_code[2]; /* signal trampoline */
	54	struct siginfo rs_info;
	55	struct ucontext rs_uc;
	56	};
	57
	58	#else
	59
66680583 RB	60	struct sigframe {
	61	u32 sf_ass[4]; /* argument save space for o32 */
	62	u32 sf_pad[2];
	63	struct sigcontext sf_sc; /* hw context */
	64	sigset_t sf_mask;
	65	u32 sf_code[8] ____cacheline_aligned; /* signal trampoline */
	66	};
	67
c0b9bae9 FBH	68	struct rt_sigframe {
	69	u32 rs_ass[4]; /* argument save space for o32 */
	70	u32 rs_pad[2];
	71	struct siginfo rs_info;
	72	struct ucontext rs_uc;
	73	u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */
	74	};
	75
	76	#endif
	77
c3fc4ab3 FBH	78	/*
	79	* Helper routines
	80	*/
	81	int setup_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
	82	{
	83	int err = 0;
	84	int i;
	85
	86	err \|= __put_user(regs->cp0_epc, &sc->sc_pc);
	87
	88	err \|= __put_user(0, &sc->sc_regs[0]);
	89	for (i = 1; i < 32; i++)
	90	err \|= __put_user(regs->regs[i], &sc->sc_regs[i]);
	91
	92	err \|= __put_user(regs->hi, &sc->sc_mdhi);
	93	err \|= __put_user(regs->lo, &sc->sc_mdlo);
	94	if (cpu_has_dsp) {
	95	err \|= __put_user(mfhi1(), &sc->sc_hi1);
	96	err \|= __put_user(mflo1(), &sc->sc_lo1);
	97	err \|= __put_user(mfhi2(), &sc->sc_hi2);
	98	err \|= __put_user(mflo2(), &sc->sc_lo2);
	99	err \|= __put_user(mfhi3(), &sc->sc_hi3);
	100	err \|= __put_user(mflo3(), &sc->sc_lo3);
	101	err \|= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
	102	}
	103
	104	err \|= __put_user(!!used_math(), &sc->sc_used_math);
	105
	106	if (used_math()) {
	107	/*
	108	* Save FPU state to signal context. Signal handler
	109	* will "inherit" current FPU state.
	110	*/
	111	preempt_disable();
	112
	113	if (!is_fpu_owner()) {
	114	own_fpu();
	115	restore_fp(current);
	116	}
	117	err \|= save_fp_context(sc);
	118
	119	preempt_enable();
	120	}
	121	return err;
	122	}
	123
	124	int restore_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
	125	{
	126	unsigned int used_math;
	127	unsigned long treg;
	128	int err = 0;
	129	int i;
	130
	131	/* Always make any pending restarted system calls return -EINTR */
	132	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	133
	134	err \|= __get_user(regs->cp0_epc, &sc->sc_pc);
	135	err \|= __get_user(regs->hi, &sc->sc_mdhi);
	136	err \|= __get_user(regs->lo, &sc->sc_mdlo);
	137	if (cpu_has_dsp) {
	138	err \|= __get_user(treg, &sc->sc_hi1); mthi1(treg);
	139	err \|= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
	140	err \|= __get_user(treg, &sc->sc_hi2); mthi2(treg);
	141	err \|= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
142	err \|= __get_user(treg, &sc->sc_hi3); mthi3(treg);
143	err \|= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
144	err \|= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
145	}
146
147	for (i = 1; i < 32; i++)
148	err \|= __get_user(regs->regs[i], &sc->sc_regs[i]);
149
150	err \|= __get_user(used_math, &sc->sc_used_math);
151	conditional_used_math(used_math);
152
153	preempt_disable();
154
155	if (used_math()) {
156	/* restore fpu context if we have used it before */
157	own_fpu();
158	err \|= restore_fp_context(sc);
159	} else {
160	/* signal handler may have used FPU. Give it up. */
161	lose_fpu();
162	}
163
164	preempt_enable();
165
166	return err;
167	}
168
169	void __user get_sigframe(struct k_sigaction ka, struct pt_regs *regs,
170	size_t frame_size)
171	{
172	unsigned long sp;
173
174	/* Default to using normal stack */
175	sp = regs->regs[29];
176
177	/*
178	* FPU emulator may have it's own trampoline active just
179	* above the user stack, 16-bytes before the next lowest
180	* 16 byte boundary. Try to avoid trashing it.
181	*/
182	sp -= 32;
183
184	/* This is the X/Open sanctioned signal stack switching. */
185	if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
186	sp = current->sas_ss_sp + current->sas_ss_size;
187
188	return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
189	}
190
191	int install_sigtramp(unsigned int __user *tramp, unsigned int syscall)
192	{
193	int err;
194
195	/*
196	* Set up the return code ...
197	*
198	* li v0, __NR__foo_sigreturn
199	* syscall
200	*/
201
202	err = __put_user(0x24020000 + syscall, tramp + 0);
601dde45	203	err \|= __put_user(0x0000000c , tramp + 1);
c3fc4ab3 FBH	204	if (ICACHE_REFILLS_WORKAROUND_WAR) {
	205	err \|= __put_user(0, tramp + 2);
	206	err \|= __put_user(0, tramp + 3);
	207	err \|= __put_user(0, tramp + 4);
	208	err \|= __put_user(0, tramp + 5);
	209	err \|= __put_user(0, tramp + 6);
	210	err \|= __put_user(0, tramp + 7);
	211	}
	212	flush_cache_sigtramp((unsigned long) tramp);
	213
	214	return err;
	215	}
	216
1da177e4 LT	217	/*
	218	* Atomically swap in the new signal mask, and wait for a signal.
	219	*/
	220
	221	#ifdef CONFIG_TRAD_SIGNALS
f90080a0	222	asmlinkage int sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
1da177e4	223	{
7b3e2fc8	224	sigset_t newset;
fe00f943	225	sigset_t __user *uset;
1da177e4	226
fe00f943	227	uset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	228	if (copy_from_user(&newset, uset, sizeof(sigset_t)))
	229	return -EFAULT;
	230	sigdelsetmask(&newset, ~_BLOCKABLE);
	231
	232	spin_lock_irq(&current->sighand->siglock);
7b3e2fc8	233	current->saved_sigmask = current->blocked;
1da177e4 LT	234	current->blocked = newset;
	235	recalc_sigpending();
	236	spin_unlock_irq(&current->sighand->siglock);
	237
7b3e2fc8 RB	238	current->state = TASK_INTERRUPTIBLE;
	239	schedule();
	240	set_thread_flag(TIF_RESTORE_SIGMASK);
	241	return -ERESTARTNOHAND;
1da177e4 LT	242	}
	243	#endif
	244
f90080a0	245	asmlinkage int sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
1da177e4	246	{
7b3e2fc8	247	sigset_t newset;
fe00f943	248	sigset_t __user *unewset;
1da177e4 LT	249	size_t sigsetsize;
	250
	251	/* XXX Don't preclude handling different sized sigset_t's. */
	252	sigsetsize = regs.regs[5];
	253	if (sigsetsize != sizeof(sigset_t))
	254	return -EINVAL;
	255
fe00f943	256	unewset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	257	if (copy_from_user(&newset, unewset, sizeof(newset)))
	258	return -EFAULT;
	259	sigdelsetmask(&newset, ~_BLOCKABLE);
	260
	261	spin_lock_irq(&current->sighand->siglock);
7b3e2fc8	262	current->saved_sigmask = current->blocked;
1da177e4	263	current->blocked = newset;
e0daad44	264	recalc_sigpending();
1da177e4 LT	265	spin_unlock_irq(&current->sighand->siglock);
1da177e4 LT	266
7b3e2fc8 RB	267	current->state = TASK_INTERRUPTIBLE;
	268	schedule();
	269	set_thread_flag(TIF_RESTORE_SIGMASK);
	270	return -ERESTARTNOHAND;
1da177e4 LT	271	}
	272
	273	#ifdef CONFIG_TRAD_SIGNALS
9c6031cc AN	274	asmlinkage int sys_sigaction(int sig, const struct sigaction __user *act,
9c6031cc AN	275	struct sigaction __user *oact)
1da177e4 LT	276	{
	277	struct k_sigaction new_ka, old_ka;
	278	int ret;
	279	int err = 0;
	280
	281	if (act) {
	282	old_sigset_t mask;
	283
	284	if (!access_ok(VERIFY_READ, act, sizeof(*act)))
	285	return -EFAULT;
	286	err \|= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
	287	err \|= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
	288	err \|= __get_user(mask, &act->sa_mask.sig[0]);
	289	if (err)
	290	return -EFAULT;
	291
	292	siginitset(&new_ka.sa.sa_mask, mask);
	293	}
	294
	295	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	296
	297	if (!ret && oact) {
	298	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
e0daad44	299	return -EFAULT;
1da177e4 LT	300	err \|= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	301	err \|= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
	302	err \|= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
	303	err \|= __put_user(0, &oact->sa_mask.sig[1]);
	304	err \|= __put_user(0, &oact->sa_mask.sig[2]);
	305	err \|= __put_user(0, &oact->sa_mask.sig[3]);
	306	if (err)
	307	return -EFAULT;
	308	}
	309
	310	return ret;
	311	}
	312	#endif
	313
	314	asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
	315	{
fe00f943 RB	316	const stack_t __user uss = (const stack_t __user ) regs.regs[4];
fe00f943 RB	317	stack_t __user uoss = (stack_t __user ) regs.regs[5];
1da177e4 LT	318	unsigned long usp = regs.regs[29];
	319
	320	return do_sigaltstack(uss, uoss, usp);
	321	}
	322
1da177e4	323	#ifdef CONFIG_TRAD_SIGNALS
f90080a0	324	asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
1da177e4	325	{
9bbf28a3	326	struct sigframe __user *frame;
1da177e4 LT	327	sigset_t blocked;
1da177e4 LT	328
9bbf28a3	329	frame = (struct sigframe __user *) regs.regs[29];
1da177e4 LT	330	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	331	goto badframe;
	332	if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
	333	goto badframe;
	334
	335	sigdelsetmask(&blocked, ~_BLOCKABLE);
	336	spin_lock_irq(&current->sighand->siglock);
	337	current->blocked = blocked;
	338	recalc_sigpending();
	339	spin_unlock_irq(&current->sighand->siglock);
	340
	341	if (restore_sigcontext(&regs, &frame->sf_sc))
	342	goto badframe;
	343
	344	/*
	345	* Don't let your children do this ...
	346	*/
1da177e4 LT	347	__asm__ __volatile__(
	348	"move\t$29, %0\n\t"
	349	"j\tsyscall_exit"
	350	:/* no outputs */
	351	:"r" (&regs));
	352	/* Unreached */
	353
	354	badframe:
	355	force_sig(SIGSEGV, current);
	356	}
e50c0a8f	357	#endif /* CONFIG_TRAD_SIGNALS */
1da177e4	358
f90080a0	359	asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
1da177e4	360	{
9bbf28a3	361	struct rt_sigframe __user *frame;
1da177e4 LT	362	sigset_t set;
	363	stack_t st;
	364
9bbf28a3	365	frame = (struct rt_sigframe __user *) regs.regs[29];
1da177e4 LT	366	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	367	goto badframe;
	368	if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
	369	goto badframe;
	370
	371	sigdelsetmask(&set, ~_BLOCKABLE);
	372	spin_lock_irq(&current->sighand->siglock);
	373	current->blocked = set;
	374	recalc_sigpending();
	375	spin_unlock_irq(&current->sighand->siglock);
	376
	377	if (restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext))
	378	goto badframe;
	379
	380	if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
	381	goto badframe;
	382	/* It is more difficult to avoid calling this function than to
	383	call it and ignore errors. */
9bbf28a3	384	do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
1da177e4 LT	385
	386	/*
	387	* Don't let your children do this ...
	388	*/
	389	__asm__ __volatile__(
	390	"move\t$29, %0\n\t"
	391	"j\tsyscall_exit"
	392	:/* no outputs */
	393	:"r" (&regs));
	394	/* Unreached */
	395
	396	badframe:
	397	force_sig(SIGSEGV, current);
	398	}
	399
	400	#ifdef CONFIG_TRAD_SIGNALS
129bc8f7	401	int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
1da177e4 LT	402	int signr, sigset_t *set)
1da177e4 LT	403	{
9bbf28a3	404	struct sigframe __user *frame;
1da177e4 LT	405	int err = 0;
	406
	407	frame = get_sigframe(ka, regs, sizeof(*frame));
	408	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	409	goto give_sigsegv;
	410
601dde45	411	err \|= install_sigtramp(frame->sf_code, __NR_sigreturn);
1da177e4 LT	412
	413	err \|= setup_sigcontext(regs, &frame->sf_sc);
	414	err \|= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
	415	if (err)
	416	goto give_sigsegv;
	417
	418	/*
	419	* Arguments to signal handler:
	420	*
	421	* a0 = signal number
	422	* a1 = 0 (should be cause)
	423	* a2 = pointer to struct sigcontext
	424	*
	425	* $25 and c0_epc point to the signal handler, $29 points to the
	426	* struct sigframe.
	427	*/
	428	regs->regs[ 4] = signr;
	429	regs->regs[ 5] = 0;
	430	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
	431	regs->regs[29] = (unsigned long) frame;
	432	regs->regs[31] = (unsigned long) frame->sf_code;
	433	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
	434
722bb63d	435	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4	436	current->comm, current->pid,
722bb63d	437	frame, regs->cp0_epc, regs->regs[31]);
e0daad44	438	return 0;
1da177e4 LT	439
	440	give_sigsegv:
	441	force_sigsegv(signr, current);
7b3e2fc8	442	return -EFAULT;
1da177e4 LT	443	}
	444	#endif
	445
129bc8f7	446	int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
1da177e4 LT	447	int signr, sigset_t set, siginfo_t info)
1da177e4 LT	448	{
9bbf28a3	449	struct rt_sigframe __user *frame;
1da177e4 LT	450	int err = 0;
	451
	452	frame = get_sigframe(ka, regs, sizeof(*frame));
	453	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	454	goto give_sigsegv;
	455
601dde45	456	err \|= install_sigtramp(frame->rs_code, __NR_rt_sigreturn);
1da177e4 LT	457
	458	/* Create siginfo. */
	459	err \|= copy_siginfo_to_user(&frame->rs_info, info);
	460
	461	/* Create the ucontext. */
	462	err \|= __put_user(0, &frame->rs_uc.uc_flags);
5665a0ac	463	err \|= __put_user(NULL, &frame->rs_uc.uc_link);
9c6031cc	464	err \|= __put_user((void __user *)current->sas_ss_sp,
1da177e4 LT	465	&frame->rs_uc.uc_stack.ss_sp);
	466	err \|= __put_user(sas_ss_flags(regs->regs[29]),
	467	&frame->rs_uc.uc_stack.ss_flags);
	468	err \|= __put_user(current->sas_ss_size,
	469	&frame->rs_uc.uc_stack.ss_size);
	470	err \|= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	471	err \|= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
	472
	473	if (err)
	474	goto give_sigsegv;
	475
	476	/*
	477	* Arguments to signal handler:
	478	*
	479	* a0 = signal number
	480	* a1 = 0 (should be cause)
	481	* a2 = pointer to ucontext
	482	*
	483	* $25 and c0_epc point to the signal handler, $29 points to
	484	* the struct rt_sigframe.
	485	*/
	486	regs->regs[ 4] = signr;
	487	regs->regs[ 5] = (unsigned long) &frame->rs_info;
	488	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
	489	regs->regs[29] = (unsigned long) frame;
	490	regs->regs[31] = (unsigned long) frame->rs_code;
	491	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
	492
722bb63d	493	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4 LT	494	current->comm, current->pid,
1da177e4 LT	495	frame, regs->cp0_epc, regs->regs[31]);
722bb63d	496
7b3e2fc8	497	return 0;
1da177e4 LT	498
	499	give_sigsegv:
	500	force_sigsegv(signr, current);
7b3e2fc8	501	return -EFAULT;
1da177e4 LT	502	}
1da177e4 LT	503
e692eb30	504	static int handle_signal(unsigned long sig, siginfo_t *info,
1da177e4 LT	505	struct k_sigaction ka, sigset_t oldset, struct pt_regs *regs)
1da177e4 LT	506	{
129bc8f7 RB	507	int ret;
129bc8f7 RB	508
1da177e4 LT	509	switch(regs->regs[0]) {
	510	case ERESTART_RESTARTBLOCK:
	511	case ERESTARTNOHAND:
	512	regs->regs[2] = EINTR;
	513	break;
	514	case ERESTARTSYS:
7b3e2fc8	515	if (!(ka->sa.sa_flags & SA_RESTART)) {
1da177e4 LT	516	regs->regs[2] = EINTR;
	517	break;
	518	}
	519	/* fallthrough */
	520	case ERESTARTNOINTR: /* Userland will reload $v0. */
	521	regs->regs[7] = regs->regs[26];
	522	regs->cp0_epc -= 8;
	523	}
	524
	525	regs->regs[0] = 0; /* Don't deal with this again. */
	526
e50c0a8f	527	if (sig_uses_siginfo(ka))
129bc8f7	528	ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
1da177e4	529	else
129bc8f7	530	ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);
1da177e4	531
69be8f18 SR	532	spin_lock_irq(&current->sighand->siglock);
	533	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
	534	if (!(ka->sa.sa_flags & SA_NODEFER))
1da177e4	535	sigaddset(&current->blocked,sig);
69be8f18 SR	536	recalc_sigpending();
69be8f18 SR	537	spin_unlock_irq(&current->sighand->siglock);
129bc8f7 RB	538
129bc8f7 RB	539	return ret;
1da177e4 LT	540	}
1da177e4 LT	541
40ac5d47	542	void do_signal(struct pt_regs *regs)
1da177e4 LT	543	{
1da177e4 LT	544	struct k_sigaction ka;
7b3e2fc8	545	sigset_t *oldset;
1da177e4 LT	546	siginfo_t info;
	547	int signr;
	548
1da177e4 LT	549	/*
	550	* We want the common case to go fast, which is why we may in certain
	551	* cases get here from kernel mode. Just return without doing anything
	552	* if so.
	553	*/
	554	if (!user_mode(regs))
40ac5d47	555	return;
1da177e4	556
7b3e2fc8 RB	557	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	558	oldset = &current->saved_sigmask;
	559	else
1da177e4 LT	560	oldset = &current->blocked;
	561
	562	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
7b3e2fc8 RB	563	if (signr > 0) {
	564	/* Whee! Actually deliver the signal. */
	565	if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
	566	/*
	567	* A signal was successfully delivered; the saved
	568	* sigmask will have been stored in the signal frame,
	569	* and will be restored by sigreturn, so we can simply
	570	* clear the TIF_RESTORE_SIGMASK flag.
	571	*/
	572	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	573	clear_thread_flag(TIF_RESTORE_SIGMASK);
	574	}
45887e12 RB	575
45887e12 RB	576	return;
7b3e2fc8	577	}
1da177e4	578
1da177e4 LT	579	/*
	580	* Who's code doesn't conform to the restartable syscall convention
	581	* dies here!!! The li instruction, a single machine instruction,
	582	* must directly be followed by the syscall instruction.
	583	*/
	584	if (regs->regs[0]) {
	585	if (regs->regs[2] == ERESTARTNOHAND \|\|
	586	regs->regs[2] == ERESTARTSYS \|\|
	587	regs->regs[2] == ERESTARTNOINTR) {
	588	regs->regs[7] = regs->regs[26];
	589	regs->cp0_epc -= 8;
	590	}
	591	if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
	592	regs->regs[2] = __NR_restart_syscall;
	593	regs->regs[7] = regs->regs[26];
	594	regs->cp0_epc -= 4;
	595	}
13fdd31a	596	regs->regs[0] = 0; /* Don't deal with this again. */
1da177e4	597	}
7b3e2fc8 RB	598
	599	/*
	600	* If there's no signal to deliver, we just put the saved sigmask
	601	* back
	602	*/
	603	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
	604	clear_thread_flag(TIF_RESTORE_SIGMASK);
	605	sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	606	}
1da177e4 LT	607	}
	608
	609	/*
	610	* notification of userspace execution resumption
7b3e2fc8	611	* - triggered by the TIF_WORK_MASK flags
1da177e4	612	*/
7b3e2fc8	613	asmlinkage void do_notify_resume(struct pt_regs regs, void unused,
1da177e4 LT	614	__u32 thread_info_flags)
	615	{
	616	/* deal with pending signal delivery */
7b3e2fc8 RB	617	if (thread_info_flags & (_TIF_SIGPENDING \| _TIF_RESTORE_SIGMASK))
7b3e2fc8 RB	618	current->thread.abi->do_signal(regs);
1da177e4	619	}