[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/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();
		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
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();

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