[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/context_tracking.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 <asm/inst.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();
		err = own_fpu_inatomic(1);
		if (!err)
			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();
		err = own_fpu_inatomic(0);
		if (!err)
			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
SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset)
{
	return sys_rt_sigsuspend(uset, sizeof(sigset_t));
}
#endif

#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;
#ifdef CONFIG_CPU_MICROMIPS
	void *vdso;
	unsigned int tmp = (unsigned int)current->mm->context.vdso;

	set_isa16_mode(tmp);
	vdso = (void *)tmp;
#else
	void *vdso = current->mm->context.vdso;
#endif

	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();

	user_exit();

	/* 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);
	}

	user_enter();
}

#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>
c3fc5cd5	11	#include <linux/context_tracking.h>
1f717929	12	#include <linux/irqflags.h>
1da177e4 LT	13	#include <linux/sched.h>
	14	#include <linux/mm.h>
	15	#include <linux/personality.h>
	16	#include <linux/smp.h>
1da177e4 LT	17	#include <linux/kernel.h>
	18	#include <linux/signal.h>
	19	#include <linux/errno.h>
	20	#include <linux/wait.h>
	21	#include <linux/ptrace.h>
	22	#include <linux/unistd.h>
	23	#include <linux/compiler.h>
dbda6ac0	24	#include <linux/syscalls.h>
faea6234	25	#include <linux/uaccess.h>
733e5e4b	26	#include <linux/tracehook.h>
1da177e4	27
e50c0a8f	28	#include <asm/abi.h>
1da177e4 LT	29	#include <asm/asm.h>
	30	#include <linux/bitops.h>
	31	#include <asm/cacheflush.h>
	32	#include <asm/fpu.h>
	33	#include <asm/sim.h>
1da177e4 LT	34	#include <asm/ucontext.h>
1da177e4 LT	35	#include <asm/cpu-features.h>
02416dcf	36	#include <asm/war.h>
d814c28c	37	#include <asm/vdso.h>
b81947c6	38	#include <asm/dsp.h>
01be057b	39	#include <asm/inst.h>
1da177e4 LT	40
	41	#include "signal-common.h"
	42
137f6f3e RB	43	static int (save_fp_context)(struct sigcontext __user sc);
	44	static int (restore_fp_context)(struct sigcontext __user sc);
	45
	46	extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
	47	extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
	48
	49	extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
	50	extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);
	51
66680583 RB	52	struct sigframe {
66680583 RB	53	u32 sf_ass[4]; /* argument save space for o32 */
d814c28c	54	u32 sf_pad[2]; /* Was: signal trampoline */
66680583 RB	55	struct sigcontext sf_sc;
	56	sigset_t sf_mask;
	57	};
	58
c0b9bae9 FBH	59	struct rt_sigframe {
c0b9bae9 FBH	60	u32 rs_ass[4]; /* argument save space for o32 */
d814c28c	61	u32 rs_pad[2]; /* Was: signal trampoline */
c0b9bae9 FBH	62	struct siginfo rs_info;
	63	struct ucontext rs_uc;
	64	};
	65
c3fc4ab3 FBH	66	/*
	67	* Helper routines
	68	*/
faea6234 AN	69	static int protected_save_fp_context(struct sigcontext __user *sc)
	70	{
	71	int err;
	72	while (1) {
	73	lock_fpu_owner();
597ce172 PB	74	err = own_fpu_inatomic(1);
	75	if (!err)
	76	err = save_fp_context(sc); /* this might fail */
faea6234 AN	77	unlock_fpu_owner();
	78	if (likely(!err))
	79	break;
	80	/* touch the sigcontext and try again */
	81	err = __put_user(0, &sc->sc_fpregs[0]) \|
	82	__put_user(0, &sc->sc_fpregs[31]) \|
	83	__put_user(0, &sc->sc_fpc_csr);
	84	if (err)
	85	break; /* really bad sigcontext */
	86	}
	87	return err;
	88	}
	89
	90	static int protected_restore_fp_context(struct sigcontext __user *sc)
	91	{
c726b822	92	int err, tmp __maybe_unused;
faea6234 AN	93	while (1) {
faea6234 AN	94	lock_fpu_owner();
597ce172 PB	95	err = own_fpu_inatomic(0);
	96	if (!err)
	97	err = restore_fp_context(sc); /* this might fail */
faea6234 AN	98	unlock_fpu_owner();
	99	if (likely(!err))
	100	break;
	101	/* touch the sigcontext and try again */
	102	err = __get_user(tmp, &sc->sc_fpregs[0]) \|
	103	__get_user(tmp, &sc->sc_fpregs[31]) \|
	104	__get_user(tmp, &sc->sc_fpc_csr);
	105	if (err)
	106	break; /* really bad sigcontext */
	107	}
	108	return err;
	109	}
	110
c3fc4ab3 FBH	111	int setup_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
	112	{
	113	int err = 0;
	114	int i;
53dc8028	115	unsigned int used_math;
c3fc4ab3 FBH	116
	117	err \|= __put_user(regs->cp0_epc, &sc->sc_pc);
	118
	119	err \|= __put_user(0, &sc->sc_regs[0]);
	120	for (i = 1; i < 32; i++)
	121	err \|= __put_user(regs->regs[i], &sc->sc_regs[i]);
	122
9693a853 FBH	123	#ifdef CONFIG_CPU_HAS_SMARTMIPS
	124	err \|= __put_user(regs->acx, &sc->sc_acx);
	125	#endif
c3fc4ab3 FBH	126	err \|= __put_user(regs->hi, &sc->sc_mdhi);
	127	err \|= __put_user(regs->lo, &sc->sc_mdlo);
	128	if (cpu_has_dsp) {
	129	err \|= __put_user(mfhi1(), &sc->sc_hi1);
	130	err \|= __put_user(mflo1(), &sc->sc_lo1);
	131	err \|= __put_user(mfhi2(), &sc->sc_hi2);
	132	err \|= __put_user(mflo2(), &sc->sc_lo2);
	133	err \|= __put_user(mfhi3(), &sc->sc_hi3);
	134	err \|= __put_user(mflo3(), &sc->sc_lo3);
	135	err \|= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
	136	}
	137
53dc8028 AN	138	used_math = !!used_math();
53dc8028 AN	139	err \|= __put_user(used_math, &sc->sc_used_math);
c3fc4ab3	140
53dc8028	141	if (used_math) {
c3fc4ab3 FBH	142	/*
	143	* Save FPU state to signal context. Signal handler
	144	* will "inherit" current FPU state.
	145	*/
faea6234	146	err \|= protected_save_fp_context(sc);
c3fc4ab3 FBH	147	}
	148	return err;
	149	}
	150
c6a2f467 AN	151	int fpcsr_pending(unsigned int __user *fpcsr)
	152	{
	153	int err, sig = 0;
	154	unsigned int csr, enabled;
	155
	156	err = __get_user(csr, fpcsr);
	157	enabled = FPU_CSR_UNI_X \| ((csr & FPU_CSR_ALL_E) << 5);
	158	/*
	159	* If the signal handler set some FPU exceptions, clear it and
	160	* send SIGFPE.
	161	*/
	162	if (csr & enabled) {
	163	csr &= ~enabled;
	164	err \|= __put_user(csr, fpcsr);
	165	sig = SIGFPE;
	166	}
	167	return err ?: sig;
	168	}
	169
	170	static int
	171	check_and_restore_fp_context(struct sigcontext __user *sc)
	172	{
	173	int err, sig;
	174
	175	err = sig = fpcsr_pending(&sc->sc_fpc_csr);
	176	if (err > 0)
	177	err = 0;
faea6234	178	err \|= protected_restore_fp_context(sc);
c6a2f467 AN	179	return err ?: sig;
	180	}
	181
c3fc4ab3 FBH	182	int restore_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
	183	{
	184	unsigned int used_math;
	185	unsigned long treg;
	186	int err = 0;
	187	int i;
	188
	189	/* Always make any pending restarted system calls return -EINTR */
	190	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	191
	192	err \|= __get_user(regs->cp0_epc, &sc->sc_pc);
9693a853 FBH	193
	194	#ifdef CONFIG_CPU_HAS_SMARTMIPS
	195	err \|= __get_user(regs->acx, &sc->sc_acx);
	196	#endif
c3fc4ab3 FBH	197	err \|= __get_user(regs->hi, &sc->sc_mdhi);
	198	err \|= __get_user(regs->lo, &sc->sc_mdlo);
	199	if (cpu_has_dsp) {
	200	err \|= __get_user(treg, &sc->sc_hi1); mthi1(treg);
	201	err \|= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
	202	err \|= __get_user(treg, &sc->sc_hi2); mthi2(treg);
	203	err \|= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
	204	err \|= __get_user(treg, &sc->sc_hi3); mthi3(treg);
	205	err \|= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
	206	err \|= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
	207	}
	208
	209	for (i = 1; i < 32; i++)
	210	err \|= __get_user(regs->regs[i], &sc->sc_regs[i]);
	211
	212	err \|= __get_user(used_math, &sc->sc_used_math);
	213	conditional_used_math(used_math);
	214
53dc8028	215	if (used_math) {
c3fc4ab3	216	/* restore fpu context if we have used it before */
c6a2f467 AN	217	if (!err)
c6a2f467 AN	218	err = check_and_restore_fp_context(sc);
c3fc4ab3 FBH	219	} else {
c3fc4ab3 FBH	220	/* signal handler may have used FPU. Give it up. */
53dc8028	221	lose_fpu(0);
c3fc4ab3 FBH	222	}
c3fc4ab3 FBH	223
c3fc4ab3 FBH	224	return err;
	225	}
	226
	227	void __user get_sigframe(struct k_sigaction ka, struct pt_regs *regs,
	228	size_t frame_size)
	229	{
	230	unsigned long sp;
	231
	232	/* Default to using normal stack */
	233	sp = regs->regs[29];
	234
	235	/*
	236	* FPU emulator may have it's own trampoline active just
	237	* above the user stack, 16-bytes before the next lowest
	238	* 16 byte boundary. Try to avoid trashing it.
	239	*/
	240	sp -= 32;
	241
	242	/* This is the X/Open sanctioned signal stack switching. */
	243	if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
	244	sp = current->sas_ss_sp + current->sas_ss_size;
	245
	246	return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
	247	}
	248
1da177e4 LT	249	/*
	250	* Atomically swap in the new signal mask, and wait for a signal.
	251	*/
	252
	253	#ifdef CONFIG_TRAD_SIGNALS
1910f4ab	254	SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset)
1da177e4	255	{
1910f4ab	256	return sys_rt_sigsuspend(uset, sizeof(sigset_t));
1da177e4 LT	257	}
	258	#endif
	259
1da177e4	260	#ifdef CONFIG_TRAD_SIGNALS
dbda6ac0 RB	261	SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
dbda6ac0 RB	262	struct sigaction __user *, oact)
1da177e4 LT	263	{
	264	struct k_sigaction new_ka, old_ka;
	265	int ret;
	266	int err = 0;
	267
	268	if (act) {
	269	old_sigset_t mask;
	270
	271	if (!access_ok(VERIFY_READ, act, sizeof(*act)))
	272	return -EFAULT;
	273	err \|= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
	274	err \|= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
	275	err \|= __get_user(mask, &act->sa_mask.sig[0]);
	276	if (err)
	277	return -EFAULT;
	278
	279	siginitset(&new_ka.sa.sa_mask, mask);
	280	}
	281
	282	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	283
	284	if (!ret && oact) {
	285	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
e0daad44	286	return -EFAULT;
1da177e4 LT	287	err \|= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	288	err \|= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
	289	err \|= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
	290	err \|= __put_user(0, &oact->sa_mask.sig[1]);
	291	err \|= __put_user(0, &oact->sa_mask.sig[2]);
	292	err \|= __put_user(0, &oact->sa_mask.sig[3]);
	293	if (err)
	294	return -EFAULT;
	295	}
	296
	297	return ret;
	298	}
	299	#endif
	300
1da177e4	301	#ifdef CONFIG_TRAD_SIGNALS
f90080a0	302	asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
1da177e4	303	{
9bbf28a3	304	struct sigframe __user *frame;
1da177e4	305	sigset_t blocked;
c6a2f467	306	int sig;
1da177e4	307
9bbf28a3	308	frame = (struct sigframe __user *) regs.regs[29];
1da177e4 LT	309	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	310	goto badframe;
	311	if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
	312	goto badframe;
	313
8598f3cd	314	set_current_blocked(&blocked);
1da177e4	315
c6a2f467 AN	316	sig = restore_sigcontext(&regs, &frame->sf_sc);
c6a2f467 AN	317	if (sig < 0)
1da177e4	318	goto badframe;
c6a2f467 AN	319	else if (sig)
c6a2f467 AN	320	force_sig(sig, current);
1da177e4 LT	321
	322	/*
	323	* Don't let your children do this ...
	324	*/
1da177e4 LT	325	__asm__ __volatile__(
	326	"move\t$29, %0\n\t"
	327	"j\tsyscall_exit"
	328	:/* no outputs */
	329	:"r" (&regs));
	330	/* Unreached */
	331
	332	badframe:
	333	force_sig(SIGSEGV, current);
	334	}
e50c0a8f	335	#endif /* CONFIG_TRAD_SIGNALS */
1da177e4	336
f90080a0	337	asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
1da177e4	338	{
9bbf28a3	339	struct rt_sigframe __user *frame;
1da177e4	340	sigset_t set;
c6a2f467	341	int sig;
1da177e4	342
9bbf28a3	343	frame = (struct rt_sigframe __user *) regs.regs[29];
1da177e4 LT	344	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	345	goto badframe;
	346	if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
	347	goto badframe;
	348
8598f3cd	349	set_current_blocked(&set);
1da177e4	350
c6a2f467 AN	351	sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
c6a2f467 AN	352	if (sig < 0)
1da177e4	353	goto badframe;
c6a2f467 AN	354	else if (sig)
c6a2f467 AN	355	force_sig(sig, current);
1da177e4	356
ea536ad4 AV	357	if (restore_altstack(&frame->rs_uc.uc_stack))
ea536ad4 AV	358	goto badframe;
1da177e4 LT	359
	360	/*
	361	* Don't let your children do this ...
	362	*/
	363	__asm__ __volatile__(
	364	"move\t$29, %0\n\t"
	365	"j\tsyscall_exit"
	366	:/* no outputs */
	367	:"r" (&regs));
	368	/* Unreached */
	369
	370	badframe:
	371	force_sig(SIGSEGV, current);
	372	}
	373
	374	#ifdef CONFIG_TRAD_SIGNALS
d814c28c DD	375	static int setup_frame(void sig_return, struct k_sigaction ka,
d814c28c DD	376	struct pt_regs regs, int signr, sigset_t set)
1da177e4	377	{
9bbf28a3	378	struct sigframe __user *frame;
1da177e4 LT	379	int err = 0;
	380
	381	frame = get_sigframe(ka, regs, sizeof(*frame));
	382	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	383	goto give_sigsegv;
	384
1da177e4 LT	385	err \|= setup_sigcontext(regs, &frame->sf_sc);
	386	err \|= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
	387	if (err)
	388	goto give_sigsegv;
	389
	390	/*
	391	* Arguments to signal handler:
	392	*
	393	* a0 = signal number
	394	* a1 = 0 (should be cause)
	395	* a2 = pointer to struct sigcontext
	396	*
	397	* $25 and c0_epc point to the signal handler, $29 points to the
	398	* struct sigframe.
	399	*/
	400	regs->regs[ 4] = signr;
	401	regs->regs[ 5] = 0;
	402	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
	403	regs->regs[29] = (unsigned long) frame;
d814c28c	404	regs->regs[31] = (unsigned long) sig_return;
1da177e4 LT	405	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
1da177e4 LT	406
722bb63d	407	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4	408	current->comm, current->pid,
722bb63d	409	frame, regs->cp0_epc, regs->regs[31]);
e0daad44	410	return 0;
1da177e4 LT	411
	412	give_sigsegv:
	413	force_sigsegv(signr, current);
7b3e2fc8	414	return -EFAULT;
1da177e4 LT	415	}
	416	#endif
	417
d814c28c	418	static int setup_rt_frame(void sig_return, struct k_sigaction ka,
70342287	419	struct pt_regs regs, int signr, sigset_t set,
d814c28c	420	siginfo_t *info)
1da177e4	421	{
9bbf28a3	422	struct rt_sigframe __user *frame;
1da177e4 LT	423	int err = 0;
	424
	425	frame = get_sigframe(ka, regs, sizeof(*frame));
	426	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
	427	goto give_sigsegv;
	428
1da177e4 LT	429	/* Create siginfo. */
	430	err \|= copy_siginfo_to_user(&frame->rs_info, info);
	431
70342287	432	/* Create the ucontext. */
1da177e4	433	err \|= __put_user(0, &frame->rs_uc.uc_flags);
5665a0ac	434	err \|= __put_user(NULL, &frame->rs_uc.uc_link);
ea536ad4	435	err \|= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
1da177e4 LT	436	err \|= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	437	err \|= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
	438
	439	if (err)
	440	goto give_sigsegv;
	441
	442	/*
	443	* Arguments to signal handler:
	444	*
	445	* a0 = signal number
	446	* a1 = 0 (should be cause)
	447	* a2 = pointer to ucontext
	448	*
	449	* $25 and c0_epc point to the signal handler, $29 points to
	450	* the struct rt_sigframe.
	451	*/
	452	regs->regs[ 4] = signr;
	453	regs->regs[ 5] = (unsigned long) &frame->rs_info;
	454	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
	455	regs->regs[29] = (unsigned long) frame;
d814c28c	456	regs->regs[31] = (unsigned long) sig_return;
1da177e4 LT	457	regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
1da177e4 LT	458
722bb63d	459	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
1da177e4 LT	460	current->comm, current->pid,
1da177e4 LT	461	frame, regs->cp0_epc, regs->regs[31]);
722bb63d	462
7b3e2fc8	463	return 0;
1da177e4 LT	464
	465	give_sigsegv:
	466	force_sigsegv(signr, current);
7b3e2fc8	467	return -EFAULT;
1da177e4 LT	468	}
1da177e4 LT	469
151fd6ac RB	470	struct mips_abi mips_abi = {
	471	#ifdef CONFIG_TRAD_SIGNALS
	472	.setup_frame = setup_frame,
d814c28c	473	.signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
151fd6ac	474	#endif
70342287	475	.setup_rt_frame = setup_rt_frame,
d814c28c DD	476	.rt_signal_return_offset =
d814c28c DD	477	offsetof(struct mips_vdso, rt_signal_trampoline),
151fd6ac RB	478	.restart = __NR_restart_syscall
	479	};
	480
a610d6e6	481	static void handle_signal(unsigned long sig, siginfo_t *info,
b7f9a11a	482	struct k_sigaction ka, struct pt_regs regs)
1da177e4	483	{
b7f9a11a	484	sigset_t *oldset = sigmask_to_save();
129bc8f7	485	int ret;
d814c28c	486	struct mips_abi *abi = current->thread.abi;
01be057b DL	487	#ifdef CONFIG_CPU_MICROMIPS
	488	void *vdso;
	489	unsigned int tmp = (unsigned int)current->mm->context.vdso;
	490
	491	set_isa16_mode(tmp);
	492	vdso = (void *)tmp;
	493	#else
d814c28c	494	void *vdso = current->mm->context.vdso;
01be057b	495	#endif
129bc8f7	496
8f5a00eb AV	497	if (regs->regs[0]) {
	498	switch(regs->regs[2]) {
	499	case ERESTART_RESTARTBLOCK:
	500	case ERESTARTNOHAND:
1da177e4 LT	501	regs->regs[2] = EINTR;
1da177e4 LT	502	break;
8f5a00eb AV	503	case ERESTARTSYS:
	504	if (!(ka->sa.sa_flags & SA_RESTART)) {
	505	regs->regs[2] = EINTR;
	506	break;
	507	}
	508	/* fallthrough */
	509	case ERESTARTNOINTR:
	510	regs->regs[7] = regs->regs[26];
	511	regs->regs[2] = regs->regs[0];
	512	regs->cp0_epc -= 4;
1da177e4	513	}
1da177e4	514
70342287	515	regs->regs[0] = 0; /* Don't deal with this again. */
8f5a00eb	516	}
1da177e4	517
e50c0a8f	518	if (sig_uses_siginfo(ka))
d814c28c DD	519	ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
d814c28c DD	520	ka, regs, sig, oldset, info);
1da177e4	521	else
d814c28c DD	522	ret = abi->setup_frame(vdso + abi->signal_return_offset,
d814c28c DD	523	ka, regs, sig, oldset);
1da177e4	524
062ab57b	525	if (ret)
a610d6e6	526	return;
062ab57b	527
efee984c	528	signal_delivered(sig, info, ka, regs, 0);
1da177e4 LT	529	}
1da177e4 LT	530
151fd6ac	531	static void do_signal(struct pt_regs *regs)
1da177e4 LT	532	{
	533	struct k_sigaction ka;
	534	siginfo_t info;
	535	int signr;
	536
1da177e4	537	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
7b3e2fc8	538	if (signr > 0) {
70342287	539	/* Whee! Actually deliver the signal. */
a610d6e6	540	handle_signal(signr, &info, &ka, regs);
45887e12	541	return;
7b3e2fc8	542	}
1da177e4	543
1da177e4	544	if (regs->regs[0]) {
9ec9b5ac RB	545	switch (regs->regs[2]) {
	546	case ERESTARTNOHAND:
	547	case ERESTARTSYS:
	548	case ERESTARTNOINTR:
8f5a00eb	549	regs->regs[2] = regs->regs[0];
1da177e4	550	regs->regs[7] = regs->regs[26];
8f5a00eb	551	regs->cp0_epc -= 4;
9ec9b5ac RB	552	break;
	553
	554	case ERESTART_RESTARTBLOCK:
151fd6ac	555	regs->regs[2] = current->thread.abi->restart;
1da177e4 LT	556	regs->regs[7] = regs->regs[26];
1da177e4 LT	557	regs->cp0_epc -= 4;
9ec9b5ac	558	break;
1da177e4	559	}
70342287	560	regs->regs[0] = 0; /* Don't deal with this again. */
1da177e4	561	}
7b3e2fc8 RB	562
	563	/*
	564	* If there's no signal to deliver, we just put the saved sigmask
	565	* back
	566	*/
51a7b448	567	restore_saved_sigmask();
1da177e4 LT	568	}
	569
	570	/*
	571	* notification of userspace execution resumption
7b3e2fc8	572	* - triggered by the TIF_WORK_MASK flags
1da177e4	573	*/
7b3e2fc8	574	asmlinkage void do_notify_resume(struct pt_regs regs, void unused,
1da177e4 LT	575	__u32 thread_info_flags)
1da177e4 LT	576	{
1f717929 RB	577	local_irq_enable();
1f717929 RB	578
c3fc5cd5 RB	579	user_exit();
c3fc5cd5 RB	580
1da177e4	581	/* deal with pending signal delivery */
6fd84c08	582	if (thread_info_flags & _TIF_SIGPENDING)
151fd6ac	583	do_signal(regs);
d0420c83 DH	584
	585	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	586	clear_thread_flag(TIF_NOTIFY_RESUME);
	587	tracehook_notify_resume(regs);
	588	}
c3fc5cd5 RB	589
c3fc5cd5 RB	590	user_enter();
1da177e4	591	}
137f6f3e RB	592
	593	#ifdef CONFIG_SMP
	594	static int smp_save_fp_context(struct sigcontext __user *sc)
	595	{
	596	return raw_cpu_has_fpu
	597	? _save_fp_context(sc)
	598	: fpu_emulator_save_context(sc);
	599	}
	600
	601	static int smp_restore_fp_context(struct sigcontext __user *sc)
	602	{
	603	return raw_cpu_has_fpu
	604	? _restore_fp_context(sc)
	605	: fpu_emulator_restore_context(sc);
	606	}
	607	#endif
	608
	609	static int signal_setup(void)
	610	{
	611	#ifdef CONFIG_SMP
	612	/* For now just do the cpu_has_fpu check when the functions are invoked */
	613	save_fp_context = smp_save_fp_context;
	614	restore_fp_context = smp_restore_fp_context;
	615	#else
	616	if (cpu_has_fpu) {
	617	save_fp_context = _save_fp_context;
	618	restore_fp_context = _restore_fp_context;
	619	} else {
	620	save_fp_context = fpu_emulator_save_context;
	621	restore_fp_context = fpu_emulator_restore_context;
	622	}
	623	#endif
	624
	625	return 0;
	626	}
	627
	628	arch_initcall(signal_setup);