[deliverable/linux.git] / arch / score / kernel / signal.c

/*
 * arch/score/kernel/signal.c
 *
 * Score Processor version.
 *
 * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
 *  Chen Liqin <liqin.chen@sunplusct.com>
 *  Lennox Wu <lennox.wu@sunplusct.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see the file COPYING, or write
 * to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/uaccess.h>
#include <linux/tracehook.h>

#include <asm/cacheflush.h>
#include <asm/syscalls.h>
#include <asm/ucontext.h>

#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

struct rt_sigframe {
	u32 rs_ass[4];		/* argument save space */
	u32 rs_code[2];		/* signal trampoline */
	struct siginfo rs_info;
	struct ucontext rs_uc;
};

static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
	int err = 0;
	unsigned long reg;

	reg = regs->cp0_epc; err |= __put_user(reg, &sc->sc_pc);
	err |= __put_user(regs->cp0_psr, &sc->sc_psr);
	err |= __put_user(regs->cp0_condition, &sc->sc_condition);


#define save_gp_reg(i) {				\
	reg = regs->regs[i];				\
	err |= __put_user(reg, &sc->sc_regs[i]);	\
} while (0)
	save_gp_reg(0); save_gp_reg(1); save_gp_reg(2);
	save_gp_reg(3); save_gp_reg(4); save_gp_reg(5);
	save_gp_reg(6);	save_gp_reg(7); save_gp_reg(8);
	save_gp_reg(9); save_gp_reg(10); save_gp_reg(11);
	save_gp_reg(12); save_gp_reg(13); save_gp_reg(14);
	save_gp_reg(15); save_gp_reg(16); save_gp_reg(17);
	save_gp_reg(18); save_gp_reg(19); save_gp_reg(20);
	save_gp_reg(21); save_gp_reg(22); save_gp_reg(23);
	save_gp_reg(24); save_gp_reg(25); save_gp_reg(26);
	save_gp_reg(27); save_gp_reg(28); save_gp_reg(29);
#undef save_gp_reg

	reg = regs->ceh; err |= __put_user(reg, &sc->sc_mdceh);
	reg = regs->cel; err |= __put_user(reg, &sc->sc_mdcel);
	err |= __put_user(regs->cp0_ecr, &sc->sc_ecr);
	err |= __put_user(regs->cp0_ema, &sc->sc_ema);

	return err;
}

static int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
	int err = 0;
	u32 reg;

	err |= __get_user(regs->cp0_epc, &sc->sc_pc);
	err |= __get_user(regs->cp0_condition, &sc->sc_condition);

	err |= __get_user(reg, &sc->sc_mdceh);
	regs->ceh = (int) reg;
	err |= __get_user(reg, &sc->sc_mdcel);
	regs->cel = (int) reg;

	err |= __get_user(reg, &sc->sc_psr);
	regs->cp0_psr = (int) reg;
	err |= __get_user(reg, &sc->sc_ecr);
	regs->cp0_ecr = (int) reg;
	err |= __get_user(reg, &sc->sc_ema);
	regs->cp0_ema = (int) reg;

#define restore_gp_reg(i) do {				\
	err |= __get_user(reg, &sc->sc_regs[i]);	\
	regs->regs[i] = reg;				\
} while (0)
	restore_gp_reg(0); restore_gp_reg(1); restore_gp_reg(2);
	restore_gp_reg(3); restore_gp_reg(4); restore_gp_reg(5);
	restore_gp_reg(6); restore_gp_reg(7); restore_gp_reg(8);
	restore_gp_reg(9); restore_gp_reg(10); restore_gp_reg(11);
	restore_gp_reg(12); restore_gp_reg(13); restore_gp_reg(14);
	restore_gp_reg(15); restore_gp_reg(16); restore_gp_reg(17);
	restore_gp_reg(18); restore_gp_reg(19);	restore_gp_reg(20);
	restore_gp_reg(21); restore_gp_reg(22); restore_gp_reg(23);
	restore_gp_reg(24); restore_gp_reg(25); restore_gp_reg(26);
	restore_gp_reg(27); restore_gp_reg(28); restore_gp_reg(29);
#undef restore_gp_reg

	return err;
}

/*
 * Determine which stack to use..
 */
static 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[0];
	sp -= 32;

	/* This is the X/Open sanctioned signal stack switching.  */
	if ((ka->sa.sa_flags & SA_ONSTACK) && (!on_sig_stack(sp)))
		sp = current->sas_ss_sp + current->sas_ss_size;

	return (void __user*)((sp - frame_size) & ~7);
}

asmlinkage long
score_sigaltstack(struct pt_regs *regs)
{
	const stack_t __user *uss = (const stack_t __user *) regs->regs[4];
	stack_t __user *uoss = (stack_t __user *) regs->regs[5];
	unsigned long usp = regs->regs[0];

	return do_sigaltstack(uss, uoss, usp);
}

asmlinkage long
score_rt_sigreturn(struct pt_regs *regs)
{
	struct rt_sigframe __user *frame;
	sigset_t set;
	stack_t st;
	int sig;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	frame = (struct rt_sigframe __user *) regs->regs[0];
	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
		goto badframe;
	if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
		goto badframe;

	sigdelsetmask(&set, ~_BLOCKABLE);
	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 (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
		goto badframe;

	/* It is more difficult to avoid calling this function than to
	   call it and ignore errors.  */
	do_sigaltstack((stack_t __user *)&st, NULL, regs->regs[0]);

	__asm__ __volatile__(
		"mv\tr0, %0\n\t"
		"la\tr8, syscall_exit\n\t"
		"br\tr8\n\t"
		: : "r" (regs) : "r8");

badframe:
	force_sig(SIGSEGV, current);

	return 0;
}

static int setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
		int signr, sigset_t *set, siginfo_t *info)
{
	struct rt_sigframe __user *frame;
	int err = 0;

	frame = get_sigframe(ka, regs, sizeof(*frame));
	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto give_sigsegv;

	/*
	 * Set up the return code ...
	 *
	 *         li      v0, __NR_rt_sigreturn
	 *         syscall
	 */
	err |= __put_user(0x87788000 + __NR_rt_sigreturn*2,
			frame->rs_code + 0);
	err |= __put_user(0x80008002, frame->rs_code + 1);
	flush_cache_sigtramp((unsigned long) frame->rs_code);

	err |= copy_siginfo_to_user(&frame->rs_info, info);
	err |= __put_user(0, &frame->rs_uc.uc_flags);
	err |= __put_user(NULL, &frame->rs_uc.uc_link);
	err |= __put_user((void __user *)current->sas_ss_sp,
				&frame->rs_uc.uc_stack.ss_sp);
	err |= __put_user(sas_ss_flags(regs->regs[0]),
				&frame->rs_uc.uc_stack.ss_flags);
	err |= __put_user(current->sas_ss_size,
				&frame->rs_uc.uc_stack.ss_size);
	err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));

	if (err)
		goto give_sigsegv;

	regs->regs[0] = (unsigned long) frame;
	regs->regs[3] = (unsigned long) frame->rs_code;
	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) ka->sa.sa_handler;
	regs->cp0_epc = (unsigned long) ka->sa.sa_handler;

	return 0;

give_sigsegv:
	force_sigsegv(signr, current);
	return -EFAULT;
}

static int handle_signal(unsigned long sig, siginfo_t *info,
	struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
{
	int ret;

	if (regs->is_syscall) {
		switch (regs->regs[4]) {
		case ERESTART_RESTARTBLOCK:
		case ERESTARTNOHAND:
			regs->regs[4] = EINTR;
			break;
		case ERESTARTSYS:
			if (!(ka->sa.sa_flags & SA_RESTART)) {
				regs->regs[4] = EINTR;
				break;
			}
		case ERESTARTNOINTR:
			regs->regs[4] = regs->orig_r4;
			regs->regs[7] = regs->orig_r7;
			regs->cp0_epc -= 8;
		}

		regs->is_syscall = 0;
	}

	/*
	 * Set up the stack frame
	 */
	ret = setup_rt_frame(ka, regs, sig, oldset, info);

	if (ret == 0)
		block_sigmask(ka, sig);

	return ret;
}

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

	/*
	 * We want the common case to go fast, which is why we may in certain
	 * cases get here from kernel mode. Just return without doing anything
	 * if so.
	 */
	if (!user_mode(regs))
		return;

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	if (signr > 0) {
		/* Actually deliver the signal.  */
		if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
			/*
			 * A signal was successfully delivered; the saved
			 * sigmask will have been stored in the signal frame,
			 * and will be restored by sigreturn, so we can simply
			 * clear the TIF_RESTORE_SIGMASK flag.
			 */
			if (test_thread_flag(TIF_RESTORE_SIGMASK))
				clear_thread_flag(TIF_RESTORE_SIGMASK);
		}

		return;
	}

	if (regs->is_syscall) {
		if (regs->regs[4] == ERESTARTNOHAND ||
		    regs->regs[4] == ERESTARTSYS ||
		    regs->regs[4] == ERESTARTNOINTR) {
			regs->regs[4] = regs->orig_r4;
			regs->regs[7] = regs->orig_r7;
			regs->cp0_epc -= 8;
		}

		if (regs->regs[4] == ERESTART_RESTARTBLOCK) {
			regs->regs[27] = __NR_restart_syscall;
			regs->regs[4] = regs->orig_r4;
			regs->regs[7] = regs->orig_r7;
			regs->cp0_epc -= 8;
		}

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

	/*
	 * If there's no signal to deliver, we just put the saved sigmask
	 * back
	 */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}
}

/*
 * notification of userspace execution resumption
 * - triggered by the TIF_WORK_MASK flags
 */
asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
				__u32 thread_info_flags)
{
	/* deal with pending signal delivery */
	if (thread_info_flags & _TIF_SIGPENDING)
		do_signal(regs);
	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
		clear_thread_flag(TIF_NOTIFY_RESUME);
		tracehook_notify_resume(regs);
	}
}
Commit	Line	Data
6bc9a396 CL	1	/*
	2	* arch/score/kernel/signal.c
	3	*
	4	* Score Processor version.
	5	*
	6	* Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
	7	* Chen Liqin <liqin.chen@sunplusct.com>
	8	* Lennox Wu <lennox.wu@sunplusct.com>
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License as published by
	12	* the Free Software Foundation; either version 2 of the License, or
	13	* (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	* GNU General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, see the file COPYING, or write
	22	* to the Free Software Foundation, Inc.,
	23	* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	24	*/
	25
	26	#include <linux/errno.h>
	27	#include <linux/signal.h>
d8aa899b	28	#include <linux/ptrace.h>
6bc9a396 CL	29	#include <linux/unistd.h>
6bc9a396 CL	30	#include <linux/uaccess.h>
1d5d4dbe	31	#include <linux/tracehook.h>
9fb24cc5	32
d8aa899b	33	#include <asm/cacheflush.h>
9fb24cc5 AB	34	#include <asm/syscalls.h>
9fb24cc5 AB	35	#include <asm/ucontext.h>
6bc9a396	36
6bc9a396 CL	37	#define _BLOCKABLE (~(sigmask(SIGKILL) \| sigmask(SIGSTOP)))
	38
	39	struct rt_sigframe {
	40	u32 rs_ass[4]; /* argument save space */
	41	u32 rs_code[2]; /* signal trampoline */
	42	struct siginfo rs_info;
	43	struct ucontext rs_uc;
	44	};
	45
bddc6059	46	static int setup_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
6bc9a396 CL	47	{
	48	int err = 0;
	49	unsigned long reg;
	50
	51	reg = regs->cp0_epc; err \|= __put_user(reg, &sc->sc_pc);
	52	err \|= __put_user(regs->cp0_psr, &sc->sc_psr);
	53	err \|= __put_user(regs->cp0_condition, &sc->sc_condition);
	54
	55
	56	#define save_gp_reg(i) { \
	57	reg = regs->regs[i]; \
	58	err \|= __put_user(reg, &sc->sc_regs[i]); \
	59	} while (0)
	60	save_gp_reg(0); save_gp_reg(1); save_gp_reg(2);
	61	save_gp_reg(3); save_gp_reg(4); save_gp_reg(5);
	62	save_gp_reg(6); save_gp_reg(7); save_gp_reg(8);
	63	save_gp_reg(9); save_gp_reg(10); save_gp_reg(11);
	64	save_gp_reg(12); save_gp_reg(13); save_gp_reg(14);
	65	save_gp_reg(15); save_gp_reg(16); save_gp_reg(17);
	66	save_gp_reg(18); save_gp_reg(19); save_gp_reg(20);
	67	save_gp_reg(21); save_gp_reg(22); save_gp_reg(23);
	68	save_gp_reg(24); save_gp_reg(25); save_gp_reg(26);
	69	save_gp_reg(27); save_gp_reg(28); save_gp_reg(29);
	70	#undef save_gp_reg
	71
	72	reg = regs->ceh; err \|= __put_user(reg, &sc->sc_mdceh);
	73	reg = regs->cel; err \|= __put_user(reg, &sc->sc_mdcel);
	74	err \|= __put_user(regs->cp0_ecr, &sc->sc_ecr);
	75	err \|= __put_user(regs->cp0_ema, &sc->sc_ema);
	76
	77	return err;
	78	}
	79
bddc6059	80	static int restore_sigcontext(struct pt_regs regs, struct sigcontext __user sc)
6bc9a396 CL	81	{
	82	int err = 0;
	83	u32 reg;
	84
	85	err \|= __get_user(regs->cp0_epc, &sc->sc_pc);
	86	err \|= __get_user(regs->cp0_condition, &sc->sc_condition);
	87
	88	err \|= __get_user(reg, &sc->sc_mdceh);
	89	regs->ceh = (int) reg;
	90	err \|= __get_user(reg, &sc->sc_mdcel);
	91	regs->cel = (int) reg;
	92
	93	err \|= __get_user(reg, &sc->sc_psr);
	94	regs->cp0_psr = (int) reg;
	95	err \|= __get_user(reg, &sc->sc_ecr);
	96	regs->cp0_ecr = (int) reg;
	97	err \|= __get_user(reg, &sc->sc_ema);
	98	regs->cp0_ema = (int) reg;
	99
	100	#define restore_gp_reg(i) do { \
	101	err \|= __get_user(reg, &sc->sc_regs[i]); \
	102	regs->regs[i] = reg; \
	103	} while (0)
	104	restore_gp_reg(0); restore_gp_reg(1); restore_gp_reg(2);
	105	restore_gp_reg(3); restore_gp_reg(4); restore_gp_reg(5);
	106	restore_gp_reg(6); restore_gp_reg(7); restore_gp_reg(8);
	107	restore_gp_reg(9); restore_gp_reg(10); restore_gp_reg(11);
	108	restore_gp_reg(12); restore_gp_reg(13); restore_gp_reg(14);
	109	restore_gp_reg(15); restore_gp_reg(16); restore_gp_reg(17);
	110	restore_gp_reg(18); restore_gp_reg(19); restore_gp_reg(20);
	111	restore_gp_reg(21); restore_gp_reg(22); restore_gp_reg(23);
	112	restore_gp_reg(24); restore_gp_reg(25); restore_gp_reg(26);
	113	restore_gp_reg(27); restore_gp_reg(28); restore_gp_reg(29);
	114	#undef restore_gp_reg
	115
	116	return err;
	117	}
	118
	119	/*
	120	* Determine which stack to use..
	121	*/
bddc6059 AB	122	static void __user get_sigframe(struct k_sigaction ka,
bddc6059 AB	123	struct pt_regs *regs, size_t frame_size)
6bc9a396 CL	124	{
	125	unsigned long sp;
	126
	127	/* Default to using normal stack */
	128	sp = regs->regs[0];
	129	sp -= 32;
	130
	131	/* This is the X/Open sanctioned signal stack switching. */
	132	if ((ka->sa.sa_flags & SA_ONSTACK) && (!on_sig_stack(sp)))
	133	sp = current->sas_ss_sp + current->sas_ss_size;
	134
a1f8213b	135	return (void __user*)((sp - frame_size) & ~7);
6bc9a396 CL	136	}
6bc9a396 CL	137
bddc6059 AB	138	asmlinkage long
bddc6059 AB	139	score_sigaltstack(struct pt_regs *regs)
6bc9a396	140	{
a1f8213b AB	141	const stack_t __user uss = (const stack_t __user ) regs->regs[4];
a1f8213b AB	142	stack_t __user uoss = (stack_t __user ) regs->regs[5];
6bc9a396 CL	143	unsigned long usp = regs->regs[0];
	144
	145	return do_sigaltstack(uss, uoss, usp);
	146	}
	147
bddc6059 AB	148	asmlinkage long
bddc6059 AB	149	score_rt_sigreturn(struct pt_regs *regs)
6bc9a396 CL	150	{
	151	struct rt_sigframe __user *frame;
	152	sigset_t set;
	153	stack_t st;
	154	int sig;
	155
f2ccfb3e AV	156	/* Always make any pending restarted system calls return -EINTR */
	157	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	158
6bc9a396 CL	159	frame = (struct rt_sigframe __user *) regs->regs[0];
	160	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	161	goto badframe;
	162	if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
	163	goto badframe;
	164
	165	sigdelsetmask(&set, ~_BLOCKABLE);
4c3181bd	166	set_current_blocked(&set);
6bc9a396 CL	167
	168	sig = restore_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	169	if (sig < 0)
	170	goto badframe;
	171	else if (sig)
	172	force_sig(sig, current);
	173
	174	if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
	175	goto badframe;
	176
	177	/* It is more difficult to avoid calling this function than to
	178	call it and ignore errors. */
	179	do_sigaltstack((stack_t __user *)&st, NULL, regs->regs[0]);
	180
	181	__asm__ __volatile__(
	182	"mv\tr0, %0\n\t"
	183	"la\tr8, syscall_exit\n\t"
	184	"br\tr8\n\t"
	185	: : "r" (regs) : "r8");
	186
	187	badframe:
	188	force_sig(SIGSEGV, current);
bddc6059 AB	189
bddc6059 AB	190	return 0;
6bc9a396 CL	191	}
6bc9a396 CL	192
bddc6059	193	static int setup_rt_frame(struct k_sigaction ka, struct pt_regs regs,
6bc9a396 CL	194	int signr, sigset_t set, siginfo_t info)
6bc9a396 CL	195	{
a1f8213b	196	struct rt_sigframe __user *frame;
6bc9a396 CL	197	int err = 0;
	198
	199	frame = get_sigframe(ka, regs, sizeof(*frame));
	200	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	201	goto give_sigsegv;
	202
	203	/*
	204	* Set up the return code ...
	205	*
	206	* li v0, __NR_rt_sigreturn
	207	* syscall
	208	*/
	209	err \|= __put_user(0x87788000 + __NR_rt_sigreturn*2,
	210	frame->rs_code + 0);
	211	err \|= __put_user(0x80008002, frame->rs_code + 1);
	212	flush_cache_sigtramp((unsigned long) frame->rs_code);
	213
	214	err \|= copy_siginfo_to_user(&frame->rs_info, info);
	215	err \|= __put_user(0, &frame->rs_uc.uc_flags);
c6067472	216	err \|= __put_user(NULL, &frame->rs_uc.uc_link);
a1f8213b	217	err \|= __put_user((void __user *)current->sas_ss_sp,
6bc9a396 CL	218	&frame->rs_uc.uc_stack.ss_sp);
	219	err \|= __put_user(sas_ss_flags(regs->regs[0]),
	220	&frame->rs_uc.uc_stack.ss_flags);
	221	err \|= __put_user(current->sas_ss_size,
	222	&frame->rs_uc.uc_stack.ss_size);
	223	err \|= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
	224	err \|= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
	225
	226	if (err)
	227	goto give_sigsegv;
	228
	229	regs->regs[0] = (unsigned long) frame;
	230	regs->regs[3] = (unsigned long) frame->rs_code;
	231	regs->regs[4] = signr;
	232	regs->regs[5] = (unsigned long) &frame->rs_info;
	233	regs->regs[6] = (unsigned long) &frame->rs_uc;
	234	regs->regs[29] = (unsigned long) ka->sa.sa_handler;
	235	regs->cp0_epc = (unsigned long) ka->sa.sa_handler;
	236
	237	return 0;
	238
	239	give_sigsegv:
cf4a0ce4	240	force_sigsegv(signr, current);
6bc9a396 CL	241	return -EFAULT;
	242	}
	243
bddc6059	244	static int handle_signal(unsigned long sig, siginfo_t *info,
6bc9a396 CL	245	struct k_sigaction ka, sigset_t oldset, struct pt_regs *regs)
	246	{
	247	int ret;
	248
	249	if (regs->is_syscall) {
	250	switch (regs->regs[4]) {
	251	case ERESTART_RESTARTBLOCK:
	252	case ERESTARTNOHAND:
	253	regs->regs[4] = EINTR;
	254	break;
	255	case ERESTARTSYS:
	256	if (!(ka->sa.sa_flags & SA_RESTART)) {
	257	regs->regs[4] = EINTR;
	258	break;
	259	}
	260	case ERESTARTNOINTR:
	261	regs->regs[4] = regs->orig_r4;
	262	regs->regs[7] = regs->orig_r7;
	263	regs->cp0_epc -= 8;
	264	}
	265
	266	regs->is_syscall = 0;
	267	}
	268
	269	/*
	270	* Set up the stack frame
	271	*/
	272	ret = setup_rt_frame(ka, regs, sig, oldset, info);
	273
4c3181bd MF	274	if (ret == 0)
4c3181bd MF	275	block_sigmask(ka, sig);
6bc9a396 CL	276
	277	return ret;
	278	}
	279
bddc6059	280	static void do_signal(struct pt_regs *regs)
6bc9a396 CL	281	{
	282	struct k_sigaction ka;
	283	sigset_t *oldset;
	284	siginfo_t info;
	285	int signr;
	286
	287	/*
	288	* We want the common case to go fast, which is why we may in certain
	289	* cases get here from kernel mode. Just return without doing anything
	290	* if so.
	291	*/
	292	if (!user_mode(regs))
	293	return;
	294
	295	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	296	oldset = &current->saved_sigmask;
	297	else
	298	oldset = &current->blocked;
	299
	300	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	301	if (signr > 0) {
	302	/* Actually deliver the signal. */
	303	if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
	304	/*
	305	* A signal was successfully delivered; the saved
	306	* sigmask will have been stored in the signal frame,
	307	* and will be restored by sigreturn, so we can simply
	308	* clear the TIF_RESTORE_SIGMASK flag.
	309	*/
	310	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	311	clear_thread_flag(TIF_RESTORE_SIGMASK);
	312	}
	313
	314	return;
	315	}
	316
	317	if (regs->is_syscall) {
	318	if (regs->regs[4] == ERESTARTNOHAND \|\|
	319	regs->regs[4] == ERESTARTSYS \|\|
	320	regs->regs[4] == ERESTARTNOINTR) {
	321	regs->regs[4] = regs->orig_r4;
	322	regs->regs[7] = regs->orig_r7;
	323	regs->cp0_epc -= 8;
	324	}
	325
	326	if (regs->regs[4] == ERESTART_RESTARTBLOCK) {
	327	regs->regs[27] = __NR_restart_syscall;
	328	regs->regs[4] = regs->orig_r4;
	329	regs->regs[7] = regs->orig_r7;
	330	regs->cp0_epc -= 8;
	331	}
	332
	333	regs->is_syscall = 0; /* Don't deal with this again. */
	334	}
	335
	336	/*
	337	* If there's no signal to deliver, we just put the saved sigmask
	338	* back
	339	*/
	340	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
	341	clear_thread_flag(TIF_RESTORE_SIGMASK);
	342	sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	343	}
	344	}
345
346	/*
347	* notification of userspace execution resumption
348	* - triggered by the TIF_WORK_MASK flags
349	*/
350	asmlinkage void do_notify_resume(struct pt_regs regs, void unused,
351	__u32 thread_info_flags)
352	{
353	/* deal with pending signal delivery */
1d5d4dbe	354	if (thread_info_flags & _TIF_SIGPENDING)
6bc9a396	355	do_signal(regs);
1d5d4dbe AV	356	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	357	clear_thread_flag(TIF_NOTIFY_RESUME);
	358	tracehook_notify_resume(regs);
1d5d4dbe	359	}
6bc9a396	360	}