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

/*
 * Signal handling
 *
 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
 * Copyright (C) 2008-2009 PetaLogix
 * Copyright (C) 2003,2004 John Williams <jwilliams@itee.uq.edu.au>
 * Copyright (C) 2001 NEC Corporation
 * Copyright (C) 2001 Miles Bader <miles@gnu.org>
 * Copyright (C) 1999,2000 Niibe Yutaka & Kaz Kojima
 * Copyright (C) 1991,1992 Linus Torvalds
 *
 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
 *
 * This file was was derived from the sh version, arch/sh/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.
 */

#include <linux/sched.h>
#include <linux/mm.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/stddef.h>
#include <linux/personality.h>
#include <linux/percpu.h>
#include <linux/linkage.h>
#include <asm/entry.h>
#include <asm/ucontext.h>
#include <linux/uaccess.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <linux/syscalls.h>
#include <asm/cacheflush.h>
#include <asm/syscalls.h>

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

asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset, int in_sycall);

asmlinkage long
sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
		struct pt_regs *regs)
{
	return do_sigaltstack(uss, uoss, regs->r1);
}

/*
 * Do a signal return; undo the signal stack.
 */
struct sigframe {
	struct sigcontext sc;
	unsigned long extramask[_NSIG_WORDS-1];
	unsigned long tramp[2];	/* signal trampoline */
};

struct rt_sigframe {
	struct siginfo info;
	struct ucontext uc;
	unsigned long tramp[2];	/* signal trampoline */
};

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

#define COPY(x)		{err |= __get_user(regs->x, &sc->regs.x); }
	COPY(r0);
	COPY(r1);
	COPY(r2);	COPY(r3);	COPY(r4);	COPY(r5);
	COPY(r6);	COPY(r7);	COPY(r8);	COPY(r9);
	COPY(r10);	COPY(r11);	COPY(r12);	COPY(r13);
	COPY(r14);	COPY(r15);	COPY(r16);	COPY(r17);
	COPY(r18);	COPY(r19);	COPY(r20);	COPY(r21);
	COPY(r22);	COPY(r23);	COPY(r24);	COPY(r25);
	COPY(r26);	COPY(r27);	COPY(r28);	COPY(r29);
	COPY(r30);	COPY(r31);
	COPY(pc);	COPY(ear);	COPY(esr);	COPY(fsr);
#undef COPY

	*rval_p = regs->r3;

	return err;
}

asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
{
	struct rt_sigframe __user *frame =
		(struct rt_sigframe __user *)(regs->r1);

	sigset_t set;
	int rval;

	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
		goto badframe;

	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
		goto badframe;

	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &rval))
		goto badframe;

	/* It is more difficult to avoid calling this function than to
	 call it and ignore errors. */
	if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->r1))
		goto badframe;

	return rval;

badframe:
	force_sig(SIGSEGV, current);
	return 0;
}

/*
 * Set up a signal frame.
 */

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

#define COPY(x)		{err |= __put_user(regs->x, &sc->regs.x); }
	COPY(r0);
	COPY(r1);
	COPY(r2);	COPY(r3);	COPY(r4);	COPY(r5);
	COPY(r6);	COPY(r7);	COPY(r8);	COPY(r9);
	COPY(r10);	COPY(r11);	COPY(r12);	COPY(r13);
	COPY(r14);	COPY(r15);	COPY(r16);	COPY(r17);
	COPY(r18);	COPY(r19);	COPY(r20);	COPY(r21);
	COPY(r22);	COPY(r23);	COPY(r24);	COPY(r25);
	COPY(r26);	COPY(r27);	COPY(r28);	COPY(r29);
	COPY(r30);	COPY(r31);
	COPY(pc);	COPY(ear);	COPY(esr);	COPY(fsr);
#undef COPY

	err |= __put_user(mask, &sc->oldmask);

	return err;
}

/*
 * Determine which stack to use..
 */
static inline void __user *
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
{
	/* Default to using normal stack */
	unsigned long sp = regs->r1;

	if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && !on_sig_stack(sp))
		sp = current->sas_ss_sp + current->sas_ss_size;

	return (void __user *)((sp - frame_size) & -8UL);
}

static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
			sigset_t *set, struct pt_regs *regs)
{
	struct rt_sigframe __user *frame;
	int err = 0;
	int signal;
	unsigned long address = 0;
#ifdef CONFIG_MMU
	pmd_t *pmdp;
	pte_t *ptep;
#endif

	frame = get_sigframe(ka, regs, sizeof(*frame));

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto give_sigsegv;

	signal = current_thread_info()->exec_domain
		&& current_thread_info()->exec_domain->signal_invmap
		&& sig < 32
		? current_thread_info()->exec_domain->signal_invmap[sig]
		: sig;

	if (info)
		err |= copy_siginfo_to_user(&frame->info, info);

	/* Create the ucontext. */
	err |= __put_user(0, &frame->uc.uc_flags);
	err |= __put_user(NULL, &frame->uc.uc_link);
	err |= __put_user((void __user *)current->sas_ss_sp,
			&frame->uc.uc_stack.ss_sp);
	err |= __put_user(sas_ss_flags(regs->r1),
			&frame->uc.uc_stack.ss_flags);
	err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
	err |= setup_sigcontext(&frame->uc.uc_mcontext,
			regs, set->sig[0]);
	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));

	/* Set up to return from userspace. If provided, use a stub
	 already in userspace. */
	/* minus 8 is offset to cater for "rtsd r15,8" */
	/* addi r12, r0, __NR_sigreturn */
	err |= __put_user(0x31800000 | __NR_rt_sigreturn ,
			frame->tramp + 0);
	/* brki r14, 0x8 */
	err |= __put_user(0xb9cc0008, frame->tramp + 1);

	/* Return from sighandler will jump to the tramp.
	 Negative 8 offset because return is rtsd r15, 8 */
	regs->r15 = ((unsigned long)frame->tramp)-8;

	address = ((unsigned long)frame->tramp);
#ifdef CONFIG_MMU
	pmdp = pmd_offset(pud_offset(
			pgd_offset(current->mm, address),
					address), address);

	preempt_disable();
	ptep = pte_offset_map(pmdp, address);
	if (pte_present(*ptep)) {
		address = (unsigned long) page_address(pte_page(*ptep));
		/* MS: I need add offset in page */
		address += ((unsigned long)frame->tramp) & ~PAGE_MASK;
		/* MS address is virtual */
		address = virt_to_phys(address);
		invalidate_icache_range(address, address + 8);
		flush_dcache_range(address, address + 8);
	}
	pte_unmap(ptep);
	preempt_enable();
#else
	flush_icache_range(address, address + 8);
	flush_dcache_range(address, address + 8);
#endif
	if (err)
		goto give_sigsegv;

	/* Set up registers for signal handler */
	regs->r1 = (unsigned long) frame;

	/* Signal handler args: */
	regs->r5 = signal; /* arg 0: signum */
	regs->r6 = (unsigned long) &frame->info; /* arg 1: siginfo */
	regs->r7 = (unsigned long) &frame->uc; /* arg2: ucontext */
	/* Offset to handle microblaze rtid r14, 0 */
	regs->pc = (unsigned long)ka->sa.sa_handler;

	set_fs(USER_DS);

	/* the tracer may want to single-step inside the handler */
	if (test_thread_flag(TIF_SINGLESTEP))
		ptrace_notify(SIGTRAP);

#ifdef DEBUG_SIG
	printk(KERN_INFO "SIG deliver (%s:%d): sp=%p pc=%08lx\n",
		current->comm, current->pid, frame, regs->pc);
#endif

	return 0;

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

/* Handle restarting system calls */
static inline void
handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
{
	switch (regs->r3) {
	case -ERESTART_RESTARTBLOCK:
	case -ERESTARTNOHAND:
		if (!has_handler)
			goto do_restart;
		regs->r3 = -EINTR;
		break;
	case -ERESTARTSYS:
		if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
			regs->r3 = -EINTR;
			break;
	}
	/* fallthrough */
	case -ERESTARTNOINTR:
do_restart:
		/* offset of 4 bytes to re-execute trap (brki) instruction */
#ifndef CONFIG_MMU
		regs->pc -= 4;
#else
		/* offset of 8 bytes required = 4 for rtbd
		   offset, plus 4 for size of
			"brki r14,8"
		   instruction. */
		regs->pc -= 8;
#endif
		break;
	}
}

/*
 * OK, we're invoking a handler
 */

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

	/* Set up the stack frame */
	if (ka->sa.sa_flags & SA_SIGINFO)
		ret = setup_rt_frame(sig, ka, info, oldset, regs);
	else
		ret = setup_rt_frame(sig, ka, NULL, oldset, regs);

	if (ret)
		return ret;

	spin_lock_irq(&current->sighand->siglock);
	sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
	if (!(ka->sa.sa_flags & SA_NODEFER))
		sigaddset(&current->blocked, sig);
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	return 0;
}

/*
 * Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 *
 * Note that we go through the signals twice: once to check the signals that
 * the kernel can handle, and then we build all the user-level signal handling
 * stack-frames in one go after that.
 */
int do_signal(struct pt_regs *regs, sigset_t *oldset, int in_syscall)
{
	siginfo_t info;
	int signr;
	struct k_sigaction ka;
#ifdef DEBUG_SIG
	printk(KERN_INFO "do signal: %p %p %d\n", regs, oldset, in_syscall);
	printk(KERN_INFO "do signal2: %lx %lx %ld [%lx]\n", regs->pc, regs->r1,
			regs->r12, current_thread_info()->flags);
#endif
	/*
	 * 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 (kernel_mode(regs))
		return 1;

	if (current_thread_info()->status & TS_RESTORE_SIGMASK)
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	if (signr > 0) {
		/* Whee! Actually deliver the signal. */
		if (in_syscall)
			handle_restart(regs, &ka, 1);
		if (!handle_signal(signr, &ka, &info, oldset, regs)) {
			/*
			 * 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 TS_RESTORE_SIGMASK flag.
			 */
			current_thread_info()->status &=
			    ~TS_RESTORE_SIGMASK;
		}
		return 1;
	}

	if (in_syscall)
		handle_restart(regs, NULL, 0);

	/*
	 * If there's no signal to deliver, we just put the saved sigmask
	 * back.
	 */
	if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
		current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}

	/* Did we come from a system call? */
	return 0;
}
Commit	Line	Data
2148daa9 MS	1	/*
	2	* Signal handling
	3	*
	4	* Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
	5	* Copyright (C) 2008-2009 PetaLogix
	6	* Copyright (C) 2003,2004 John Williams <jwilliams@itee.uq.edu.au>
	7	* Copyright (C) 2001 NEC Corporation
	8	* Copyright (C) 2001 Miles Bader <miles@gnu.org>
	9	* Copyright (C) 1999,2000 Niibe Yutaka & Kaz Kojima
	10	* Copyright (C) 1991,1992 Linus Torvalds
	11	*
	12	* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
	13	*
	14	* This file was was derived from the sh version, arch/sh/kernel/signal.c
	15	*
	16	* This file is subject to the terms and conditions of the GNU General
	17	* Public License. See the file COPYING in the main directory of this
	18	* archive for more details.
	19	*/
	20
	21	#include <linux/sched.h>
	22	#include <linux/mm.h>
	23	#include <linux/smp.h>
2148daa9 MS	24	#include <linux/kernel.h>
	25	#include <linux/signal.h>
	26	#include <linux/errno.h>
	27	#include <linux/wait.h>
	28	#include <linux/ptrace.h>
	29	#include <linux/unistd.h>
	30	#include <linux/stddef.h>
	31	#include <linux/personality.h>
	32	#include <linux/percpu.h>
	33	#include <linux/linkage.h>
	34	#include <asm/entry.h>
	35	#include <asm/ucontext.h>
	36	#include <linux/uaccess.h>
	37	#include <asm/pgtable.h>
	38	#include <asm/pgalloc.h>
2148daa9 MS	39	#include <linux/syscalls.h>
	40	#include <asm/cacheflush.h>
	41	#include <asm/syscalls.h>
	42
	43	#define _BLOCKABLE (~(sigmask(SIGKILL) \| sigmask(SIGSTOP)))
	44
	45	asmlinkage int do_signal(struct pt_regs regs, sigset_t oldset, int in_sycall);
	46
e513588f	47	asmlinkage long
2148daa9 MS	48	sys_sigaltstack(const stack_t __user uss, stack_t __user uoss,
	49	struct pt_regs *regs)
	50	{
	51	return do_sigaltstack(uss, uoss, regs->r1);
	52	}
	53
	54	/*
	55	* Do a signal return; undo the signal stack.
	56	*/
2148daa9 MS	57	struct sigframe {
	58	struct sigcontext sc;
	59	unsigned long extramask[_NSIG_WORDS-1];
	60	unsigned long tramp[2]; /* signal trampoline */
	61	};
	62
	63	struct rt_sigframe {
	64	struct siginfo info;
	65	struct ucontext uc;
	66	unsigned long tramp[2]; /* signal trampoline */
	67	};
	68
353b431b AB	69	static int restore_sigcontext(struct pt_regs *regs,
353b431b AB	70	struct sigcontext __user sc, int rval_p)
2148daa9 MS	71	{
	72	unsigned int err = 0;
	73
	74	#define COPY(x) {err \|= __get_user(regs->x, &sc->regs.x); }
	75	COPY(r0);
	76	COPY(r1);
	77	COPY(r2); COPY(r3); COPY(r4); COPY(r5);
	78	COPY(r6); COPY(r7); COPY(r8); COPY(r9);
	79	COPY(r10); COPY(r11); COPY(r12); COPY(r13);
	80	COPY(r14); COPY(r15); COPY(r16); COPY(r17);
	81	COPY(r18); COPY(r19); COPY(r20); COPY(r21);
	82	COPY(r22); COPY(r23); COPY(r24); COPY(r25);
	83	COPY(r26); COPY(r27); COPY(r28); COPY(r29);
	84	COPY(r30); COPY(r31);
	85	COPY(pc); COPY(ear); COPY(esr); COPY(fsr);
	86	#undef COPY
	87
	88	*rval_p = regs->r3;
	89
	90	return err;
	91	}
	92
3183e068	93	asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
2148daa9	94	{
353b431b	95	struct rt_sigframe __user *frame =
6e83557c	96	(struct rt_sigframe __user *)(regs->r1);
2921e2bd	97
2148daa9	98	sigset_t set;
2148daa9 MS	99	int rval;
	100
	101	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	102	goto badframe;
	103
	104	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
	105	goto badframe;
	106
	107	sigdelsetmask(&set, ~_BLOCKABLE);
	108	spin_lock_irq(&current->sighand->siglock);
	109	current->blocked = set;
	110	recalc_sigpending();
	111	spin_unlock_irq(&current->sighand->siglock);
	112
	113	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &rval))
	114	goto badframe;
	115
2148daa9 MS	116	/* It is more difficult to avoid calling this function than to
2148daa9 MS	117	call it and ignore errors. */
353b431b AB	118	if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->r1))
353b431b AB	119	goto badframe;
2148daa9 MS	120
	121	return rval;
	122
	123	badframe:
	124	force_sig(SIGSEGV, current);
	125	return 0;
	126	}
	127
	128	/*
	129	* Set up a signal frame.
	130	*/
	131
	132	static int
353b431b	133	setup_sigcontext(struct sigcontext __user sc, struct pt_regs regs,
2148daa9 MS	134	unsigned long mask)
	135	{
	136	int err = 0;
	137
	138	#define COPY(x) {err \|= __put_user(regs->x, &sc->regs.x); }
	139	COPY(r0);
	140	COPY(r1);
	141	COPY(r2); COPY(r3); COPY(r4); COPY(r5);
	142	COPY(r6); COPY(r7); COPY(r8); COPY(r9);
	143	COPY(r10); COPY(r11); COPY(r12); COPY(r13);
	144	COPY(r14); COPY(r15); COPY(r16); COPY(r17);
	145	COPY(r18); COPY(r19); COPY(r20); COPY(r21);
	146	COPY(r22); COPY(r23); COPY(r24); COPY(r25);
	147	COPY(r26); COPY(r27); COPY(r28); COPY(r29);
	148	COPY(r30); COPY(r31);
	149	COPY(pc); COPY(ear); COPY(esr); COPY(fsr);
	150	#undef COPY
	151
	152	err \|= __put_user(mask, &sc->oldmask);
	153
	154	return err;
	155	}
	156
	157	/*
	158	* Determine which stack to use..
	159	*/
353b431b	160	static inline void __user *
2148daa9 MS	161	get_sigframe(struct k_sigaction ka, struct pt_regs regs, size_t frame_size)
	162	{
	163	/* Default to using normal stack */
	164	unsigned long sp = regs->r1;
	165
	166	if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && !on_sig_stack(sp))
	167	sp = current->sas_ss_sp + current->sas_ss_size;
	168
353b431b	169	return (void __user *)((sp - frame_size) & -8UL);
2148daa9 MS	170	}
2148daa9 MS	171
bcb8c8d0	172	static int setup_rt_frame(int sig, struct k_sigaction ka, siginfo_t info,
2148daa9 MS	173	sigset_t set, struct pt_regs regs)
2148daa9 MS	174	{
353b431b	175	struct rt_sigframe __user *frame;
2148daa9 MS	176	int err = 0;
2148daa9 MS	177	int signal;
2ee2ff87 MS	178	unsigned long address = 0;
	179	#ifdef CONFIG_MMU
	180	pmd_t *pmdp;
	181	pte_t *ptep;
	182	#endif
2148daa9 MS	183
	184	frame = get_sigframe(ka, regs, sizeof(*frame));
	185
	186	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	187	goto give_sigsegv;
	188
	189	signal = current_thread_info()->exec_domain
	190	&& current_thread_info()->exec_domain->signal_invmap
	191	&& sig < 32
	192	? current_thread_info()->exec_domain->signal_invmap[sig]
	193	: sig;
	194
a6029d1c MS	195	if (info)
a6029d1c MS	196	err \|= copy_siginfo_to_user(&frame->info, info);
2148daa9 MS	197
	198	/* Create the ucontext. */
	199	err \|= __put_user(0, &frame->uc.uc_flags);
2cfedb97 MS	200	err \|= __put_user(NULL, &frame->uc.uc_link);
2cfedb97 MS	201	err \|= __put_user((void __user *)current->sas_ss_sp,
2148daa9 MS	202	&frame->uc.uc_stack.ss_sp);
	203	err \|= __put_user(sas_ss_flags(regs->r1),
	204	&frame->uc.uc_stack.ss_flags);
	205	err \|= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
	206	err \|= setup_sigcontext(&frame->uc.uc_mcontext,
	207	regs, set->sig[0]);
	208	err \|= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
	209
	210	/* Set up to return from userspace. If provided, use a stub
	211	already in userspace. */
	212	/* minus 8 is offset to cater for "rtsd r15,8" */
3183e068 AB	213	/* addi r12, r0, __NR_sigreturn */
	214	err \|= __put_user(0x31800000 \| __NR_rt_sigreturn ,
	215	frame->tramp + 0);
	216	/* brki r14, 0x8 */
	217	err \|= __put_user(0xb9cc0008, frame->tramp + 1);
	218
	219	/* Return from sighandler will jump to the tramp.
	220	Negative 8 offset because return is rtsd r15, 8 */
	221	regs->r15 = ((unsigned long)frame->tramp)-8;
	222
2ee2ff87 MS	223	address = ((unsigned long)frame->tramp);
	224	#ifdef CONFIG_MMU
	225	pmdp = pmd_offset(pud_offset(
	226	pgd_offset(current->mm, address),
	227	address), address);
	228
	229	preempt_disable();
	230	ptep = pte_offset_map(pmdp, address);
	231	if (pte_present(*ptep)) {
	232	address = (unsigned long) page_address(pte_page(*ptep));
	233	/* MS: I need add offset in page */
	234	address += ((unsigned long)frame->tramp) & ~PAGE_MASK;
	235	/* MS address is virtual */
	236	address = virt_to_phys(address);
	237	invalidate_icache_range(address, address + 8);
	238	flush_dcache_range(address, address + 8);
	239	}
	240	pte_unmap(ptep);
	241	preempt_enable();
	242	#else
	243	flush_icache_range(address, address + 8);
	244	flush_dcache_range(address, address + 8);
	245	#endif
2148daa9 MS	246	if (err)
	247	goto give_sigsegv;
	248
	249	/* Set up registers for signal handler */
6e83557c	250	regs->r1 = (unsigned long) frame;
2921e2bd	251
2148daa9 MS	252	/* Signal handler args: */
	253	regs->r5 = signal; /* arg 0: signum */
	254	regs->r6 = (unsigned long) &frame->info; /* arg 1: siginfo */
	255	regs->r7 = (unsigned long) &frame->uc; /* arg2: ucontext */
	256	/* Offset to handle microblaze rtid r14, 0 */
	257	regs->pc = (unsigned long)ka->sa.sa_handler;
	258
	259	set_fs(USER_DS);
	260
a01523cd MS	261	/* the tracer may want to single-step inside the handler */
	262	if (test_thread_flag(TIF_SINGLESTEP))
	263	ptrace_notify(SIGTRAP);
	264
2148daa9 MS	265	#ifdef DEBUG_SIG
	266	printk(KERN_INFO "SIG deliver (%s:%d): sp=%p pc=%08lx\n",
	267	current->comm, current->pid, frame, regs->pc);
	268	#endif
	269
bcb8c8d0	270	return 0;
2148daa9 MS	271
2148daa9 MS	272	give_sigsegv:
de8f2ddd	273	force_sigsegv(sig, current);
bcb8c8d0	274	return -EFAULT;
2148daa9 MS	275	}
	276
	277	/* Handle restarting system calls */
	278	static inline void
	279	handle_restart(struct pt_regs regs, struct k_sigaction ka, int has_handler)
	280	{
	281	switch (regs->r3) {
	282	case -ERESTART_RESTARTBLOCK:
	283	case -ERESTARTNOHAND:
	284	if (!has_handler)
	285	goto do_restart;
	286	regs->r3 = -EINTR;
	287	break;
	288	case -ERESTARTSYS:
	289	if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
	290	regs->r3 = -EINTR;
	291	break;
	292	}
	293	/* fallthrough */
	294	case -ERESTARTNOINTR:
	295	do_restart:
	296	/* offset of 4 bytes to re-execute trap (brki) instruction */
8b28626a	297	#ifndef CONFIG_MMU
2148daa9	298	regs->pc -= 4;
8b28626a MS	299	#else
	300	/* offset of 8 bytes required = 4 for rtbd
	301	offset, plus 4 for size of
	302	"brki r14,8"
	303	instruction. */
	304	regs->pc -= 8;
	305	#endif
2148daa9 MS	306	break;
	307	}
	308	}
	309
	310	/*
	311	* OK, we're invoking a handler
	312	*/
	313
3183e068	314	static int
2148daa9 MS	315	handle_signal(unsigned long sig, struct k_sigaction *ka,
	316	siginfo_t info, sigset_t oldset, struct pt_regs *regs)
	317	{
bcb8c8d0 MF	318	int ret;
bcb8c8d0 MF	319
2148daa9 MS	320	/* Set up the stack frame */
2148daa9 MS	321	if (ka->sa.sa_flags & SA_SIGINFO)
bcb8c8d0	322	ret = setup_rt_frame(sig, ka, info, oldset, regs);
2148daa9	323	else
bcb8c8d0 MF	324	ret = setup_rt_frame(sig, ka, NULL, oldset, regs);
	325
	326	if (ret)
	327	return ret;
2148daa9	328
bcb8c8d0 MF	329	spin_lock_irq(&current->sighand->siglock);
	330	sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
	331	if (!(ka->sa.sa_flags & SA_NODEFER))
2148daa9	332	sigaddset(&current->blocked, sig);
bcb8c8d0 MF	333	recalc_sigpending();
	334	spin_unlock_irq(&current->sighand->siglock);
	335
	336	return 0;
2148daa9 MS	337	}
	338
	339	/*
	340	* Note that 'init' is a special process: it doesn't get signals it doesn't
	341	* want to handle. Thus you cannot kill init even with a SIGKILL even by
	342	* mistake.
	343	*
	344	* Note that we go through the signals twice: once to check the signals that
	345	* the kernel can handle, and then we build all the user-level signal handling
	346	* stack-frames in one go after that.
	347	*/
	348	int do_signal(struct pt_regs regs, sigset_t oldset, int in_syscall)
	349	{
	350	siginfo_t info;
	351	int signr;
	352	struct k_sigaction ka;
	353	#ifdef DEBUG_SIG
	354	printk(KERN_INFO "do signal: %p %p %d\n", regs, oldset, in_syscall);
	355	printk(KERN_INFO "do signal2: %lx %lx %ld [%lx]\n", regs->pc, regs->r1,
	356	regs->r12, current_thread_info()->flags);
	357	#endif
	358	/*
	359	* We want the common case to go fast, which
	360	* is why we may in certain cases get here from
	361	* kernel mode. Just return without doing anything
	362	* if so.
	363	*/
	364	if (kernel_mode(regs))
	365	return 1;
	366
3183e068 AB	367	if (current_thread_info()->status & TS_RESTORE_SIGMASK)
	368	oldset = &current->saved_sigmask;
	369	else
2148daa9 MS	370	oldset = &current->blocked;
	371
	372	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	373	if (signr > 0) {
	374	/* Whee! Actually deliver the signal. */
	375	if (in_syscall)
	376	handle_restart(regs, &ka, 1);
bcb8c8d0	377	if (!handle_signal(signr, &ka, &info, oldset, regs)) {
3183e068 AB	378	/*
	379	* A signal was successfully delivered; the saved
	380	* sigmask will have been stored in the signal frame,
	381	* and will be restored by sigreturn, so we can simply
	382	* clear the TS_RESTORE_SIGMASK flag.
	383	*/
	384	current_thread_info()->status &=
	385	~TS_RESTORE_SIGMASK;
	386	}
2148daa9 MS	387	return 1;
	388	}
	389
	390	if (in_syscall)
	391	handle_restart(regs, NULL, 0);
	392
3183e068 AB	393	/*
	394	* If there's no signal to deliver, we just put the saved sigmask
	395	* back.
	396	*/
	397	if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
	398	current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
	399	sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	400	}
	401
2148daa9 MS	402	/* Did we come from a system call? */
	403	return 0;
	404	}