[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/irqflags.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/personality.h>
#include <linux/smp.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 <linux/syscalls.h>
#include <linux/uaccess.h>
#include <linux/tracehook.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/ucontext.h>
#include <asm/cpu-features.h>
#include <asm/war.h>
#include <asm/vdso.h>
#include <asm/dsp.h>

#include "signal-common.h"

static int (*save_fp_context)(struct sigcontext __user *sc);
static int (*restore_fp_context)(struct sigcontext __user *sc);

extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);

extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);

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

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

/*
 * Helper routines
 */
static int protected_save_fp_context(struct sigcontext __user *sc)
{
	int err;
	while (1) {
		lock_fpu_owner();
		own_fpu_inatomic(1);
		err = save_fp_context(sc); /* this might fail */
		unlock_fpu_owner();
		if (likely(!err))
			break;
		/* touch the sigcontext and try again */
		err = __put_user(0, &sc->sc_fpregs[0]) |
			__put_user(0, &sc->sc_fpregs[31]) |
			__put_user(0, &sc->sc_fpc_csr);
		if (err)
			break;	/* really bad sigcontext */
	}
	return err;
}

static int protected_restore_fp_context(struct sigcontext __user *sc)
{
	int err, tmp __maybe_unused;
	while (1) {
		lock_fpu_owner();
		own_fpu_inatomic(0);
		err = restore_fp_context(sc); /* this might fail */
		unlock_fpu_owner();
		if (likely(!err))
			break;
		/* touch the sigcontext and try again */
		err = __get_user(tmp, &sc->sc_fpregs[0]) |
			__get_user(tmp, &sc->sc_fpregs[31]) |
			__get_user(tmp, &sc->sc_fpc_csr);
		if (err)
			break;	/* really bad sigcontext */
	}
	return err;
}

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

	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]);

#ifdef CONFIG_CPU_HAS_SMARTMIPS
	err |= __put_user(regs->acx, &sc->sc_acx);
#endif
	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);
	}

	used_math = !!used_math();
	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.
		 */
		err |= protected_save_fp_context(sc);
	}
	return err;
}

int fpcsr_pending(unsigned int __user *fpcsr)
{
	int err, sig = 0;
	unsigned int csr, enabled;

	err = __get_user(csr, fpcsr);
	enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
	/*
	 * If the signal handler set some FPU exceptions, clear it and
	 * send SIGFPE.
	 */
	if (csr & enabled) {
		csr &= ~enabled;
		err |= __put_user(csr, fpcsr);
		sig = SIGFPE;
	}
	return err ?: sig;
}

static int
check_and_restore_fp_context(struct sigcontext __user *sc)
{
	int err, sig;

	err = sig = fpcsr_pending(&sc->sc_fpc_csr);
	if (err > 0)
		err = 0;
	err |= protected_restore_fp_context(sc);
	return err ?: sig;
}

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);

#ifdef CONFIG_CPU_HAS_SMARTMIPS
	err |= __get_user(regs->acx, &sc->sc_acx);
#endif
	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);

	if (used_math) {
		/* restore fpu context if we have used it before */
		if (!err)
			err = check_and_restore_fp_context(sc);
	} else {
		/* signal handler may have used FPU.  Give it up. */
		lose_fpu(0);
	}

	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));
}

/*
 * 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;
	return sigsuspend(&newset);
}
#endif

SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *,unewset, size_t, sigsetsize)
{
	sigset_t newset;

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

	if (copy_from_user(&newset, unewset, sizeof(newset)))
		return -EFAULT;
	return sigsuspend(&newset);
}

#ifdef CONFIG_TRAD_SIGNALS
SYSCALL_DEFINE3(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

#ifdef CONFIG_TRAD_SIGNALS
asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
{
	struct sigframe __user *frame;
	sigset_t blocked;
	int sig;

	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;

	set_current_blocked(&blocked);

	sig = restore_sigcontext(&regs, &frame->sf_sc);
	if (sig < 0)
		goto badframe;
	else if (sig)
		force_sig(sig, current);

	/*
	 * 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;
	int sig;

	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;

	set_current_blocked(&set);

	sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
	if (sig < 0)
		goto badframe;
	else if (sig)
		force_sig(sig, current);

	if (restore_altstack(&frame->rs_uc.uc_stack))
		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);
}

#ifdef CONFIG_TRAD_SIGNALS
static int setup_frame(void *sig_return, 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 |= 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) sig_return;
	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

static int setup_rt_frame(void *sig_return, 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;

	/* 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 |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
	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) sig_return;
	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;
}

struct mips_abi mips_abi = {
#ifdef CONFIG_TRAD_SIGNALS
	.setup_frame	= setup_frame,
	.signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
#endif
	.setup_rt_frame	= setup_rt_frame,
	.rt_signal_return_offset =
		offsetof(struct mips_vdso, rt_signal_trampoline),
	.restart	= __NR_restart_syscall
};

static void handle_signal(unsigned long sig, siginfo_t *info,
	struct k_sigaction *ka, struct pt_regs *regs)
{
	sigset_t *oldset = sigmask_to_save();
	int ret;
	struct mips_abi *abi = current->thread.abi;
	void *vdso = current->mm->context.vdso;

	if (regs->regs[0]) {
		switch(regs->regs[2]) {
		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:
			regs->regs[7] = regs->regs[26];
			regs->regs[2] = regs->regs[0];
			regs->cp0_epc -= 4;
		}

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

	if (sig_uses_siginfo(ka))
		ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
					  ka, regs, sig, oldset, info);
	else
		ret = abi->setup_frame(vdso + abi->signal_return_offset,
				       ka, regs, sig, oldset);

	if (ret)
		return;

	signal_delivered(sig, info, ka, regs, 0);
}

static void do_signal(struct pt_regs *regs)
{
	struct k_sigaction ka;
	siginfo_t info;
	int signr;

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

	if (regs->regs[0]) {
		switch (regs->regs[2]) {
		case ERESTARTNOHAND:
		case ERESTARTSYS:
		case ERESTARTNOINTR:
			regs->regs[2] = regs->regs[0];
			regs->regs[7] = regs->regs[26];
			regs->cp0_epc -= 4;
			break;

		case ERESTART_RESTARTBLOCK:
			regs->regs[2] = current->thread.abi->restart;
			regs->regs[7] = regs->regs[26];
			regs->cp0_epc -= 4;
			break;
		}
		regs->regs[0] = 0;	/* Don't deal with this again.  */
	}

	/*
	 * If there's no signal to deliver, we just put the saved sigmask
	 * back
	 */
	restore_saved_sigmask();
}

/*
 * 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)
{
	local_irq_enable();

	/* deal with pending signal delivery */
	if (thread_info_flags & _TIF_SIGPENDING)
		do_signal(regs);

	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
		clear_thread_flag(TIF_NOTIFY_RESUME);
		tracehook_notify_resume(regs);
	}
}

#ifdef CONFIG_SMP
static int smp_save_fp_context(struct sigcontext __user *sc)
{
	return raw_cpu_has_fpu
	       ? _save_fp_context(sc)
	       : fpu_emulator_save_context(sc);
}

static int smp_restore_fp_context(struct sigcontext __user *sc)
{
	return raw_cpu_has_fpu
	       ? _restore_fp_context(sc)
	       : fpu_emulator_restore_context(sc);
}
#endif

static int signal_setup(void)
{
#ifdef CONFIG_SMP
	/* For now just do the cpu_has_fpu check when the functions are invoked */
	save_fp_context = smp_save_fp_context;
	restore_fp_context = smp_restore_fp_context;
#else
	if (cpu_has_fpu) {
		save_fp_context = _save_fp_context;
		restore_fp_context = _restore_fp_context;
	} else {
		save_fp_context = fpu_emulator_save_context;
		restore_fp_context = fpu_emulator_restore_context;
	}
#endif

	return 0;
}

arch_initcall(signal_setup);
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>
1f717929	11	#include <linux/irqflags.h>
1da177e4 LT	12	#include <linux/sched.h>
	13	#include <linux/mm.h>
	14	#include <linux/personality.h>
	15	#include <linux/smp.h>
1da177e4 LT	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>
dbda6ac0	23	#include <linux/syscalls.h>
faea6234	24	#include <linux/uaccess.h>
733e5e4b	25	#include <linux/tracehook.h>
1da177e4	26
e50c0a8f	27	#include <asm/abi.h>
1da177e4 LT	28	#include <asm/asm.h>
	29	#include <linux/bitops.h>
	30	#include <asm/cacheflush.h>
	31	#include <asm/fpu.h>
	32	#include <asm/sim.h>
1da177e4 LT	33	#include <asm/ucontext.h>
1da177e4 LT	34	#include <asm/cpu-features.h>
02416dcf	35	#include <asm/war.h>
d814c28c	36	#include <asm/vdso.h>
b81947c6	37	#include <asm/dsp.h>
1da177e4 LT	38
	39	#include "signal-common.h"
	40
137f6f3e RB	41	static int (save_fp_context)(struct sigcontext __user sc);
	42	static int (restore_fp_context)(struct sigcontext __user sc);
	43
	44	extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
	45	extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
	46
	47	extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
	48	extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);
	49
66680583 RB	50	struct sigframe {
66680583 RB	51	u32 sf_ass[4]; /* argument save space for o32 */
d814c28c	52	u32 sf_pad[2]; /* Was: signal trampoline */
66680583 RB	53	struct sigcontext sf_sc;
	54	sigset_t sf_mask;
	55	};
	56
c0b9bae9 FBH	57	struct rt_sigframe {
c0b9bae9 FBH	58	u32 rs_ass[4]; /* argument save space for o32 */
d814c28c	59	u32 rs_pad[2]; /* Was: signal trampoline */
c0b9bae9 FBH	60	struct siginfo rs_info;
	61	struct ucontext rs_uc;
	62	};
	63
c3fc4ab3 FBH	64	/*
	65	* Helper routines
	66	*/
faea6234 AN	67	static int protected_save_fp_context(struct sigcontext __user *sc)
	68	{
	69	int err;
	70	while (1) {
	71	lock_fpu_owner();
	72	own_fpu_inatomic(1);
	73	err = save_fp_context(sc); /* this might fail */
	74	unlock_fpu_owner();
	75	if (likely(!err))
	76	break;
	77	/* touch the sigcontext and try again */
	78	err = __put_user(0, &sc->sc_fpregs[0]) \|
	79	__put_user(0, &sc->sc_fpregs[31]) \|
	80	__put_user(0, &sc->sc_fpc_csr);
	81	if (err)
	82	break; /* really bad sigcontext */
	83	}
	84	return err;
	85	}
	86
	87	static int protected_restore_fp_context(struct sigcontext __user *sc)
	88	{
c726b822	89	int err, tmp __maybe_unused;
faea6234 AN	90	while (1) {
	91	lock_fpu_owner();
	92	own_fpu_inatomic(0);
	93	err = restore_fp_context(sc); /* this might fail */
	94	unlock_fpu_owner();
	95	if (likely(!err))
	96	break;
	97	/* touch the sigcontext and try again */
	98	err = __get_user(tmp, &sc->sc_fpregs[0]) \|
	99	__get_user(tmp, &sc->sc_fpregs[31]) \|
	100	__get_user(tmp, &sc->sc_fpc_csr);
	101	if (err)
	102	break; /* really bad sigcontext */
	103	}
	104	return err;
	105	}
	106
c3fc4ab3 FBH	107	int setup_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
	108	{
	109	int err = 0;
	110	int i;
53dc8028	111	unsigned int used_math;
c3fc4ab3 FBH	112
	113	err \|= __put_user(regs->cp0_epc, &sc->sc_pc);
	114
	115	err \|= __put_user(0, &sc->sc_regs[0]);
	116	for (i = 1; i < 32; i++)
	117	err \|= __put_user(regs->regs[i], &sc->sc_regs[i]);
	118
9693a853 FBH	119	#ifdef CONFIG_CPU_HAS_SMARTMIPS
	120	err \|= __put_user(regs->acx, &sc->sc_acx);
	121	#endif
c3fc4ab3 FBH	122	err \|= __put_user(regs->hi, &sc->sc_mdhi);
	123	err \|= __put_user(regs->lo, &sc->sc_mdlo);
	124	if (cpu_has_dsp) {
	125	err \|= __put_user(mfhi1(), &sc->sc_hi1);
	126	err \|= __put_user(mflo1(), &sc->sc_lo1);
	127	err \|= __put_user(mfhi2(), &sc->sc_hi2);
	128	err \|= __put_user(mflo2(), &sc->sc_lo2);
	129	err \|= __put_user(mfhi3(), &sc->sc_hi3);
	130	err \|= __put_user(mflo3(), &sc->sc_lo3);
	131	err \|= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
	132	}
	133
53dc8028 AN	134	used_math = !!used_math();
53dc8028 AN	135	err \|= __put_user(used_math, &sc->sc_used_math);
c3fc4ab3	136
53dc8028	137	if (used_math) {
c3fc4ab3 FBH	138	/*
	139	* Save FPU state to signal context. Signal handler
	140	* will "inherit" current FPU state.
	141	*/
faea6234	142	err \|= protected_save_fp_context(sc);
c3fc4ab3 FBH	143	}
	144	return err;
	145	}
	146
c6a2f467 AN	147	int fpcsr_pending(unsigned int __user *fpcsr)
	148	{
	149	int err, sig = 0;
	150	unsigned int csr, enabled;
	151
	152	err = __get_user(csr, fpcsr);
	153	enabled = FPU_CSR_UNI_X \| ((csr & FPU_CSR_ALL_E) << 5);
	154	/*
	155	* If the signal handler set some FPU exceptions, clear it and
	156	* send SIGFPE.
	157	*/
	158	if (csr & enabled) {
	159	csr &= ~enabled;
	160	err \|= __put_user(csr, fpcsr);
	161	sig = SIGFPE;
	162	}
	163	return err ?: sig;
	164	}
	165
	166	static int
	167	check_and_restore_fp_context(struct sigcontext __user *sc)
	168	{
	169	int err, sig;
	170
	171	err = sig = fpcsr_pending(&sc->sc_fpc_csr);
	172	if (err > 0)
	173	err = 0;
faea6234	174	err \|= protected_restore_fp_context(sc);
c6a2f467 AN	175	return err ?: sig;
	176	}
	177
c3fc4ab3 FBH	178	int restore_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
	179	{
	180	unsigned int used_math;
	181	unsigned long treg;
	182	int err = 0;
	183	int i;
	184
	185	/* Always make any pending restarted system calls return -EINTR */
	186	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	187
	188	err \|= __get_user(regs->cp0_epc, &sc->sc_pc);
9693a853 FBH	189
	190	#ifdef CONFIG_CPU_HAS_SMARTMIPS
	191	err \|= __get_user(regs->acx, &sc->sc_acx);
	192	#endif
c3fc4ab3 FBH	193	err \|= __get_user(regs->hi, &sc->sc_mdhi);
	194	err \|= __get_user(regs->lo, &sc->sc_mdlo);
	195	if (cpu_has_dsp) {
	196	err \|= __get_user(treg, &sc->sc_hi1); mthi1(treg);
	197	err \|= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
	198	err \|= __get_user(treg, &sc->sc_hi2); mthi2(treg);
	199	err \|= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
	200	err \|= __get_user(treg, &sc->sc_hi3); mthi3(treg);
	201	err \|= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
	202	err \|= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
	203	}
	204
	205	for (i = 1; i < 32; i++)
	206	err \|= __get_user(regs->regs[i], &sc->sc_regs[i]);
	207
	208	err \|= __get_user(used_math, &sc->sc_used_math);
	209	conditional_used_math(used_math);
	210
53dc8028	211	if (used_math) {
c3fc4ab3	212	/* restore fpu context if we have used it before */
c6a2f467 AN	213	if (!err)
c6a2f467 AN	214	err = check_and_restore_fp_context(sc);
c3fc4ab3 FBH	215	} else {
c3fc4ab3 FBH	216	/* signal handler may have used FPU. Give it up. */
53dc8028	217	lose_fpu(0);
c3fc4ab3 FBH	218	}
c3fc4ab3 FBH	219
c3fc4ab3 FBH	220	return err;
	221	}
	222
	223	void __user get_sigframe(struct k_sigaction ka, struct pt_regs *regs,
	224	size_t frame_size)
	225	{
	226	unsigned long sp;
	227
	228	/* Default to using normal stack */
	229	sp = regs->regs[29];
	230
	231	/*
	232	* FPU emulator may have it's own trampoline active just
	233	* above the user stack, 16-bytes before the next lowest
	234	* 16 byte boundary. Try to avoid trashing it.
	235	*/
	236	sp -= 32;
	237
	238	/* This is the X/Open sanctioned signal stack switching. */
	239	if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
	240	sp = current->sas_ss_sp + current->sas_ss_size;
	241
	242	return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
	243	}
	244
1da177e4 LT	245	/*
	246	* Atomically swap in the new signal mask, and wait for a signal.
	247	*/
	248
	249	#ifdef CONFIG_TRAD_SIGNALS
f90080a0	250	asmlinkage int sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
1da177e4	251	{
7b3e2fc8	252	sigset_t newset;
fe00f943	253	sigset_t __user *uset;
1da177e4	254
fe00f943	255	uset = (sigset_t __user *) regs.regs[4];
1da177e4 LT	256	if (copy_from_user(&newset, uset, sizeof(sigset_t)))
1da177e4 LT	257	return -EFAULT;
68f3f16d	258	return sigsuspend(&newset);
1da177e4 LT	259	}
	260	#endif
	261
709410a0	262	SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *,unewset, size_t, sigsetsize)
1da177e4	263	{
7b3e2fc8	264	sigset_t newset;
1da177e4 LT	265
1da177e4 LT	266	/* XXX Don't preclude handling different sized sigset_t's. */
1da177e4 LT	267	if (sigsetsize != sizeof(sigset_t))
	268	return -EINVAL;
	269
1da177e4 LT	270	if (copy_from_user(&newset, unewset, sizeof(newset)))
1da177e4 LT	271	return -EFAULT;
68f3f16d	272	return sigsuspend(&newset);
1da177e4 LT	273	}
	274
	275	#ifdef CONFIG_TRAD_SIGNALS
dbda6ac0 RB	276	SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
dbda6ac0 RB	277	struct sigaction __user *, oact)
1da177e4 LT	278	{
	279	struct k_sigaction new_ka, old_ka;
	280	int ret;
	281	int err = 0;
	282
	283	if (act) {
	284	old_sigset_t mask;
	285
	286	if (!access_ok(VERIFY_READ, act, sizeof(*act)))
	287	return -EFAULT;
	288	err \|= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
	289	err \|= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
	290	err \|= __get_user(mask, &act->sa_mask.sig[0]);
	291	if (err)
	292	return -EFAULT;
	293
	294	siginitset(&new_ka.sa.sa_mask, mask);
	295	}
	296
	297	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	298
	299	if (!ret && oact) {
	300	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
e0daad44	301	return -EFAULT;
1da177e4 LT	302	err \|= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	303	err \|= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
	304	err \|= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
	305	err \|= __put_user(0, &oact->sa_mask.sig[1]);
	306	err \|= __put_user(0, &oact->sa_mask.sig[2]);
	307	err \|= __put_user(0, &oact->sa_mask.sig[3]);
	308	if (err)
	309	return -EFAULT;
	310	}
	311
	312	return ret;
	313	}
	314	#endif
	315
1da177e4	316	#ifdef CONFIG_TRAD_SIGNALS
f90080a0	317	asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
1da177e4	318	{
9bbf28a3	319	struct sigframe __user *frame;
1da177e4	320	sigset_t blocked;
c6a2f467	321	int sig;
1da177e4	322
9bbf28a3	323	frame = (struct sigframe __user *) regs.regs[29];
1da177e4 LT	324	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	325	goto badframe;
	326	if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
	327	goto badframe;
	328
8598f3cd	329	set_current_blocked(&blocked);
1da177e4	330
c6a2f467 AN	331	sig = restore_sigcontext(&regs, &frame->sf_sc);
c6a2f467 AN	332	if (sig < 0)
1da177e4	333	goto badframe;
c6a2f467 AN	334	else if (sig)
c6a2f467 AN	335	force_sig(sig, current);
1da177e4 LT	336
	337	/*
	338	* Don't let your children do this ...
	339	*/
1da177e4 LT	340	__asm__ __volatile__(
	341	"move\t$29, %0\n\t"
	342	"j\tsyscall_exit"
	343	:/* no outputs */
	344	:"r" (&regs));
	345	/* Unreached */
	346
	347	badframe:
	348	force_sig(SIGSEGV, current);
	349	}
e50c0a8f	350	#endif /* CONFIG_TRAD_SIGNALS */
1da177e4	351
f90080a0	352	asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
1da177e4	353	{
9bbf28a3	354	struct rt_sigframe __user *frame;
1da177e4	355	sigset_t set;
c6a2f467	356	int sig;
1da177e4	357
9bbf28a3	358	frame = (struct rt_sigframe __user *) regs.regs[29];
1da177e4 LT	359	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	360	goto badframe;
	361	if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
	362	goto badframe;
	363
8598f3cd	364	set_current_blocked(&set);
1da177e4	365
c6a2f467 AN	366	sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
c6a2f467 AN	367	if (sig < 0)
1da177e4	368	goto badframe;
c6a2f467 AN	369	else if (sig)
c6a2f467 AN	370	force_sig(sig, current);
1da177e4	371
ea536ad4 AV	372	if (restore_altstack(&frame->rs_uc.uc_stack))
ea536ad4 AV	373	goto badframe;
1da177e4 LT	374
	375	/*
	376	* Don't let your children do this ...
	377	*/
	378	__asm__ __volatile__(
	379	"move\t$29, %0\n\t"
	380	"j\tsyscall_exit"
	381	:/* no outputs */
	382	:"r" (&regs));
	383	/* Unreached */
	384
	385	badframe:
	386	force_sig(SIGSEGV, current);
	387	}
	388
	389	#ifdef CONFIG_TRAD_SIGNALS
d814c28c DD	390	static int setup_frame(void sig_return, struct k_sigaction ka,
d814c28c DD	391	struct pt_regs regs, int signr, sigset_t set)
1da177e4	392	{
9bbf28a3	393	struct sigframe __user *frame;
1da177e4 LT	394	int err = 0;
	395
	396	frame = get_sigframe(ka, regs, sizeof(*frame));
	397	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	398	goto give_sigsegv;
	399
1da177e4 LT	400	err \|= setup_sigcontext(regs, &frame->sf_sc);
	401	err \|= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
	402	if (err)
	403	goto give_sigsegv;
	404
	405	/*
	406	* Arguments to signal handler:
	407	*
	408	* a0 = signal number
	409	* a1 = 0 (should be cause)
	410	* a2 = pointer to struct sigcontext
	411	*
	412	* $25 and c0_epc point to the signal handler, $29 points to the
	413	* struct sigframe.
	414	*/
	415	regs->regs[ 4] = signr;
	416	regs->regs[ 5] = 0;
	417	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
	418	regs->regs[29] = (unsigned long) frame;
d814c28c	419	regs->regs[31] = (unsigned long) sig_return;
1da177e4 LT	420	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
1da177e4 LT	421
722bb63d	422	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4	423	current->comm, current->pid,
722bb63d	424	frame, regs->cp0_epc, regs->regs[31]);
e0daad44	425	return 0;
1da177e4 LT	426
	427	give_sigsegv:
	428	force_sigsegv(signr, current);
7b3e2fc8	429	return -EFAULT;
1da177e4 LT	430	}
	431	#endif
	432
d814c28c DD	433	static int setup_rt_frame(void sig_return, struct k_sigaction ka,
	434	struct pt_regs regs, int signr, sigset_t set,
	435	siginfo_t *info)
1da177e4	436	{
9bbf28a3	437	struct rt_sigframe __user *frame;
1da177e4 LT	438	int err = 0;
	439
	440	frame = get_sigframe(ka, regs, sizeof(*frame));
	441	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	442	goto give_sigsegv;
	443
1da177e4 LT	444	/* Create siginfo. */
	445	err \|= copy_siginfo_to_user(&frame->rs_info, info);
	446
	447	/* Create the ucontext. */
	448	err \|= __put_user(0, &frame->rs_uc.uc_flags);
5665a0ac	449	err \|= __put_user(NULL, &frame->rs_uc.uc_link);
ea536ad4	450	err \|= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
1da177e4 LT	451	err \|= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	452	err \|= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
	453
	454	if (err)
	455	goto give_sigsegv;
	456
	457	/*
	458	* Arguments to signal handler:
	459	*
	460	* a0 = signal number
	461	* a1 = 0 (should be cause)
	462	* a2 = pointer to ucontext
	463	*
	464	* $25 and c0_epc point to the signal handler, $29 points to
	465	* the struct rt_sigframe.
	466	*/
	467	regs->regs[ 4] = signr;
	468	regs->regs[ 5] = (unsigned long) &frame->rs_info;
	469	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
	470	regs->regs[29] = (unsigned long) frame;
d814c28c	471	regs->regs[31] = (unsigned long) sig_return;
1da177e4 LT	472	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
1da177e4 LT	473
722bb63d	474	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4 LT	475	current->comm, current->pid,
1da177e4 LT	476	frame, regs->cp0_epc, regs->regs[31]);
722bb63d	477
7b3e2fc8	478	return 0;
1da177e4 LT	479
	480	give_sigsegv:
	481	force_sigsegv(signr, current);
7b3e2fc8	482	return -EFAULT;
1da177e4 LT	483	}
1da177e4 LT	484
151fd6ac RB	485	struct mips_abi mips_abi = {
	486	#ifdef CONFIG_TRAD_SIGNALS
	487	.setup_frame = setup_frame,
d814c28c	488	.signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
151fd6ac RB	489	#endif
151fd6ac RB	490	.setup_rt_frame = setup_rt_frame,
d814c28c DD	491	.rt_signal_return_offset =
d814c28c DD	492	offsetof(struct mips_vdso, rt_signal_trampoline),
151fd6ac RB	493	.restart = __NR_restart_syscall
	494	};
	495
a610d6e6	496	static void handle_signal(unsigned long sig, siginfo_t *info,
b7f9a11a	497	struct k_sigaction ka, struct pt_regs regs)
1da177e4	498	{
b7f9a11a	499	sigset_t *oldset = sigmask_to_save();
129bc8f7	500	int ret;
d814c28c DD	501	struct mips_abi *abi = current->thread.abi;
d814c28c DD	502	void *vdso = current->mm->context.vdso;
129bc8f7	503
8f5a00eb AV	504	if (regs->regs[0]) {
	505	switch(regs->regs[2]) {
	506	case ERESTART_RESTARTBLOCK:
	507	case ERESTARTNOHAND:
1da177e4 LT	508	regs->regs[2] = EINTR;
1da177e4 LT	509	break;
8f5a00eb AV	510	case ERESTARTSYS:
	511	if (!(ka->sa.sa_flags & SA_RESTART)) {
	512	regs->regs[2] = EINTR;
	513	break;
	514	}
	515	/* fallthrough */
	516	case ERESTARTNOINTR:
	517	regs->regs[7] = regs->regs[26];
	518	regs->regs[2] = regs->regs[0];
	519	regs->cp0_epc -= 4;
1da177e4	520	}
1da177e4	521
8f5a00eb AV	522	regs->regs[0] = 0; /* Don't deal with this again. */
8f5a00eb AV	523	}
1da177e4	524
e50c0a8f	525	if (sig_uses_siginfo(ka))
d814c28c DD	526	ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
d814c28c DD	527	ka, regs, sig, oldset, info);
1da177e4	528	else
d814c28c DD	529	ret = abi->setup_frame(vdso + abi->signal_return_offset,
d814c28c DD	530	ka, regs, sig, oldset);
1da177e4	531
062ab57b	532	if (ret)
a610d6e6	533	return;
062ab57b	534
efee984c	535	signal_delivered(sig, info, ka, regs, 0);
1da177e4 LT	536	}
1da177e4 LT	537
151fd6ac	538	static void do_signal(struct pt_regs *regs)
1da177e4 LT	539	{
	540	struct k_sigaction ka;
	541	siginfo_t info;
	542	int signr;
	543
1da177e4	544	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
7b3e2fc8 RB	545	if (signr > 0) {
7b3e2fc8 RB	546	/* Whee! Actually deliver the signal. */
a610d6e6	547	handle_signal(signr, &info, &ka, regs);
45887e12	548	return;
7b3e2fc8	549	}
1da177e4	550
1da177e4	551	if (regs->regs[0]) {
9ec9b5ac RB	552	switch (regs->regs[2]) {
	553	case ERESTARTNOHAND:
	554	case ERESTARTSYS:
	555	case ERESTARTNOINTR:
8f5a00eb	556	regs->regs[2] = regs->regs[0];
1da177e4	557	regs->regs[7] = regs->regs[26];
8f5a00eb	558	regs->cp0_epc -= 4;
9ec9b5ac RB	559	break;
	560
	561	case ERESTART_RESTARTBLOCK:
151fd6ac	562	regs->regs[2] = current->thread.abi->restart;
1da177e4 LT	563	regs->regs[7] = regs->regs[26];
1da177e4 LT	564	regs->cp0_epc -= 4;
9ec9b5ac	565	break;
1da177e4	566	}
13fdd31a	567	regs->regs[0] = 0; /* Don't deal with this again. */
1da177e4	568	}
7b3e2fc8 RB	569
	570	/*
	571	* If there's no signal to deliver, we just put the saved sigmask
	572	* back
	573	*/
51a7b448	574	restore_saved_sigmask();
1da177e4 LT	575	}
	576
	577	/*
	578	* notification of userspace execution resumption
7b3e2fc8	579	* - triggered by the TIF_WORK_MASK flags
1da177e4	580	*/
7b3e2fc8	581	asmlinkage void do_notify_resume(struct pt_regs regs, void unused,
1da177e4 LT	582	__u32 thread_info_flags)
1da177e4 LT	583	{
1f717929 RB	584	local_irq_enable();
1f717929 RB	585
1da177e4	586	/* deal with pending signal delivery */
6fd84c08	587	if (thread_info_flags & _TIF_SIGPENDING)
151fd6ac	588	do_signal(regs);
d0420c83 DH	589
	590	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	591	clear_thread_flag(TIF_NOTIFY_RESUME);
	592	tracehook_notify_resume(regs);
	593	}
1da177e4	594	}
137f6f3e RB	595
	596	#ifdef CONFIG_SMP
	597	static int smp_save_fp_context(struct sigcontext __user *sc)
	598	{
	599	return raw_cpu_has_fpu
	600	? _save_fp_context(sc)
	601	: fpu_emulator_save_context(sc);
	602	}
	603
	604	static int smp_restore_fp_context(struct sigcontext __user *sc)
	605	{
	606	return raw_cpu_has_fpu
	607	? _restore_fp_context(sc)
	608	: fpu_emulator_restore_context(sc);
	609	}
	610	#endif
	611
	612	static int signal_setup(void)
	613	{
	614	#ifdef CONFIG_SMP
	615	/* For now just do the cpu_has_fpu check when the functions are invoked */
	616	save_fp_context = smp_save_fp_context;
	617	restore_fp_context = smp_restore_fp_context;
	618	#else
	619	if (cpu_has_fpu) {
	620	save_fp_context = _save_fp_context;
	621	restore_fp_context = _restore_fp_context;
	622	} else {
	623	save_fp_context = fpu_emulator_save_context;
	624	restore_fp_context = fpu_emulator_restore_context;
	625	}
	626	#endif
	627
	628	return 0;
	629	}
	630
	631	arch_initcall(signal_setup);