[mirror_ubuntu-artful-kernel.git] / include / linux / signal.h

#ifndef _LINUX_SIGNAL_H
#define _LINUX_SIGNAL_H

#include <linux/list.h>
#include <linux/bug.h>
#include <uapi/linux/signal.h>

struct task_struct;

/* for sysctl */
extern int print_fatal_signals;
/*
 * Real Time signals may be queued.
 */

struct sigqueue {
	struct list_head list;
	int flags;
	siginfo_t info;
	struct user_struct *user;
};

/* flags values. */
#define SIGQUEUE_PREALLOC	1

struct sigpending {
	struct list_head list;
	sigset_t signal;
};

#ifndef HAVE_ARCH_COPY_SIGINFO

#include <linux/string.h>

static inline void copy_siginfo(struct siginfo *to, struct siginfo *from)
{
	if (from->si_code < 0)
		memcpy(to, from, sizeof(*to));
	else
		/* _sigchld is currently the largest know union member */
		memcpy(to, from, __ARCH_SI_PREAMBLE_SIZE + sizeof(from->_sifields._sigchld));
}

#endif

/*
 * Define some primitives to manipulate sigset_t.
 */

#ifndef __HAVE_ARCH_SIG_BITOPS
#include <linux/bitops.h>

/* We don't use <linux/bitops.h> for these because there is no need to
   be atomic.  */
static inline void sigaddset(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	if (_NSIG_WORDS == 1)
		set->sig[0] |= 1UL << sig;
	else
		set->sig[sig / _NSIG_BPW] |= 1UL << (sig % _NSIG_BPW);
}

static inline void sigdelset(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	if (_NSIG_WORDS == 1)
		set->sig[0] &= ~(1UL << sig);
	else
		set->sig[sig / _NSIG_BPW] &= ~(1UL << (sig % _NSIG_BPW));
}

static inline int sigismember(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	if (_NSIG_WORDS == 1)
		return 1 & (set->sig[0] >> sig);
	else
		return 1 & (set->sig[sig / _NSIG_BPW] >> (sig % _NSIG_BPW));
}

#endif /* __HAVE_ARCH_SIG_BITOPS */

static inline int sigisemptyset(sigset_t *set)
{
	switch (_NSIG_WORDS) {
	case 4:
		return (set->sig[3] | set->sig[2] |
			set->sig[1] | set->sig[0]) == 0;
	case 2:
		return (set->sig[1] | set->sig[0]) == 0;
	case 1:
		return set->sig[0] == 0;
	default:
		BUILD_BUG();
		return 0;
	}
}

#define sigmask(sig)	(1UL << ((sig) - 1))

#ifndef __HAVE_ARCH_SIG_SETOPS
#include <linux/string.h>

#define _SIG_SET_BINOP(name, op)					\
static inline void name(sigset_t *r, const sigset_t *a, const sigset_t *b) \
{									\
	unsigned long a0, a1, a2, a3, b0, b1, b2, b3;			\
									\
	switch (_NSIG_WORDS) {						\
	case 4:								\
		a3 = a->sig[3]; a2 = a->sig[2];				\
		b3 = b->sig[3]; b2 = b->sig[2];				\
		r->sig[3] = op(a3, b3);					\
		r->sig[2] = op(a2, b2);					\
	case 2:								\
		a1 = a->sig[1]; b1 = b->sig[1];				\
		r->sig[1] = op(a1, b1);					\
	case 1:								\
		a0 = a->sig[0]; b0 = b->sig[0];				\
		r->sig[0] = op(a0, b0);					\
		break;							\
	default:							\
		BUILD_BUG();						\
	}								\
}

#define _sig_or(x,y)	((x) | (y))
_SIG_SET_BINOP(sigorsets, _sig_or)

#define _sig_and(x,y)	((x) & (y))
_SIG_SET_BINOP(sigandsets, _sig_and)

#define _sig_andn(x,y)	((x) & ~(y))
_SIG_SET_BINOP(sigandnsets, _sig_andn)

#undef _SIG_SET_BINOP
#undef _sig_or
#undef _sig_and
#undef _sig_andn

#define _SIG_SET_OP(name, op)						\
static inline void name(sigset_t *set)					\
{									\
	switch (_NSIG_WORDS) {						\
	case 4:	set->sig[3] = op(set->sig[3]);				\
		set->sig[2] = op(set->sig[2]);				\
	case 2:	set->sig[1] = op(set->sig[1]);				\
	case 1:	set->sig[0] = op(set->sig[0]);				\
		    break;						\
	default:							\
		BUILD_BUG();						\
	}								\
}

#define _sig_not(x)	(~(x))
_SIG_SET_OP(signotset, _sig_not)

#undef _SIG_SET_OP
#undef _sig_not

static inline void sigemptyset(sigset_t *set)
{
	switch (_NSIG_WORDS) {
	default:
		memset(set, 0, sizeof(sigset_t));
		break;
	case 2: set->sig[1] = 0;
	case 1:	set->sig[0] = 0;
		break;
	}
}

static inline void sigfillset(sigset_t *set)
{
	switch (_NSIG_WORDS) {
	default:
		memset(set, -1, sizeof(sigset_t));
		break;
	case 2: set->sig[1] = -1;
	case 1:	set->sig[0] = -1;
		break;
	}
}

/* Some extensions for manipulating the low 32 signals in particular.  */

static inline void sigaddsetmask(sigset_t *set, unsigned long mask)
{
	set->sig[0] |= mask;
}

static inline void sigdelsetmask(sigset_t *set, unsigned long mask)
{
	set->sig[0] &= ~mask;
}

static inline int sigtestsetmask(sigset_t *set, unsigned long mask)
{
	return (set->sig[0] & mask) != 0;
}

static inline void siginitset(sigset_t *set, unsigned long mask)
{
	set->sig[0] = mask;
	switch (_NSIG_WORDS) {
	default:
		memset(&set->sig[1], 0, sizeof(long)*(_NSIG_WORDS-1));
		break;
	case 2: set->sig[1] = 0;
	case 1: ;
	}
}

static inline void siginitsetinv(sigset_t *set, unsigned long mask)
{
	set->sig[0] = ~mask;
	switch (_NSIG_WORDS) {
	default:
		memset(&set->sig[1], -1, sizeof(long)*(_NSIG_WORDS-1));
		break;
	case 2: set->sig[1] = -1;
	case 1: ;
	}
}

#endif /* __HAVE_ARCH_SIG_SETOPS */

static inline void init_sigpending(struct sigpending *sig)
{
	sigemptyset(&sig->signal);
	INIT_LIST_HEAD(&sig->list);
}

extern void flush_sigqueue(struct sigpending *queue);

/* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
static inline int valid_signal(unsigned long sig)
{
	return sig <= _NSIG ? 1 : 0;
}

struct timespec;
struct pt_regs;

extern int next_signal(struct sigpending *pending, sigset_t *mask);
extern int do_send_sig_info(int sig, struct siginfo *info,
				struct task_struct *p, bool group);
extern int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p);
extern int __group_send_sig_info(int, struct siginfo *, struct task_struct *);
extern int do_sigtimedwait(const sigset_t *, siginfo_t *,
				const struct timespec *);
extern int sigprocmask(int, sigset_t *, sigset_t *);
extern void set_current_blocked(sigset_t *);
extern void __set_current_blocked(const sigset_t *);
extern int show_unhandled_signals;

struct sigaction {
#ifndef __ARCH_HAS_IRIX_SIGACTION
	__sighandler_t	sa_handler;
	unsigned long	sa_flags;
#else
	unsigned int	sa_flags;
	__sighandler_t	sa_handler;
#endif
#ifdef __ARCH_HAS_SA_RESTORER
	__sigrestore_t sa_restorer;
#endif
	sigset_t	sa_mask;	/* mask last for extensibility */
};

struct k_sigaction {
	struct sigaction sa;
#ifdef __ARCH_HAS_KA_RESTORER
	__sigrestore_t ka_restorer;
#endif
};
 
#ifdef CONFIG_OLD_SIGACTION
struct old_sigaction {
	__sighandler_t sa_handler;
	old_sigset_t sa_mask;
	unsigned long sa_flags;
	__sigrestore_t sa_restorer;
};
#endif

struct ksignal {
	struct k_sigaction ka;
	siginfo_t info;
	int sig;
};

extern int get_signal(struct ksignal *ksig);
extern void signal_setup_done(int failed, struct ksignal *ksig, int stepping);
extern void exit_signals(struct task_struct *tsk);
extern void kernel_sigaction(int, __sighandler_t);

static inline void allow_signal(int sig)
{
	/*
	 * Kernel threads handle their own signals. Let the signal code
	 * know it'll be handled, so that they don't get converted to
	 * SIGKILL or just silently dropped.
	 */
	kernel_sigaction(sig, (__force __sighandler_t)2);
}

static inline void disallow_signal(int sig)
{
	kernel_sigaction(sig, SIG_IGN);
}

extern struct kmem_cache *sighand_cachep;

int unhandled_signal(struct task_struct *tsk, int sig);

/*
 * In POSIX a signal is sent either to a specific thread (Linux task)
 * or to the process as a whole (Linux thread group).  How the signal
 * is sent determines whether it's to one thread or the whole group,
 * which determines which signal mask(s) are involved in blocking it
 * from being delivered until later.  When the signal is delivered,
 * either it's caught or ignored by a user handler or it has a default
 * effect that applies to the whole thread group (POSIX process).
 *
 * The possible effects an unblocked signal set to SIG_DFL can have are:
 *   ignore	- Nothing Happens
 *   terminate	- kill the process, i.e. all threads in the group,
 * 		  similar to exit_group.  The group leader (only) reports
 *		  WIFSIGNALED status to its parent.
 *   coredump	- write a core dump file describing all threads using
 *		  the same mm and then kill all those threads
 *   stop 	- stop all the threads in the group, i.e. TASK_STOPPED state
 *
 * SIGKILL and SIGSTOP cannot be caught, blocked, or ignored.
 * Other signals when not blocked and set to SIG_DFL behaves as follows.
 * The job control signals also have other special effects.
 *
 *	+--------------------+------------------+
 *	|  POSIX signal      |  default action  |
 *	+--------------------+------------------+
 *	|  SIGHUP            |  terminate	|
 *	|  SIGINT            |	terminate	|
 *	|  SIGQUIT           |	coredump 	|
 *	|  SIGILL            |	coredump 	|
 *	|  SIGTRAP           |	coredump 	|
 *	|  SIGABRT/SIGIOT    |	coredump 	|
 *	|  SIGBUS            |	coredump 	|
 *	|  SIGFPE            |	coredump 	|
 *	|  SIGKILL           |	terminate(+)	|
 *	|  SIGUSR1           |	terminate	|
 *	|  SIGSEGV           |	coredump 	|
 *	|  SIGUSR2           |	terminate	|
 *	|  SIGPIPE           |	terminate	|
 *	|  SIGALRM           |	terminate	|
 *	|  SIGTERM           |	terminate	|
 *	|  SIGCHLD           |	ignore   	|
 *	|  SIGCONT           |	ignore(*)	|
 *	|  SIGSTOP           |	stop(*)(+)  	|
 *	|  SIGTSTP           |	stop(*)  	|
 *	|  SIGTTIN           |	stop(*)  	|
 *	|  SIGTTOU           |	stop(*)  	|
 *	|  SIGURG            |	ignore   	|
 *	|  SIGXCPU           |	coredump 	|
 *	|  SIGXFSZ           |	coredump 	|
 *	|  SIGVTALRM         |	terminate	|
 *	|  SIGPROF           |	terminate	|
 *	|  SIGPOLL/SIGIO     |	terminate	|
 *	|  SIGSYS/SIGUNUSED  |	coredump 	|
 *	|  SIGSTKFLT         |	terminate	|
 *	|  SIGWINCH          |	ignore   	|
 *	|  SIGPWR            |	terminate	|
 *	|  SIGRTMIN-SIGRTMAX |	terminate       |
 *	+--------------------+------------------+
 *	|  non-POSIX signal  |  default action  |
 *	+--------------------+------------------+
 *	|  SIGEMT            |  coredump	|
 *	+--------------------+------------------+
 *
 * (+) For SIGKILL and SIGSTOP the action is "always", not just "default".
 * (*) Special job control effects:
 * When SIGCONT is sent, it resumes the process (all threads in the group)
 * from TASK_STOPPED state and also clears any pending/queued stop signals
 * (any of those marked with "stop(*)").  This happens regardless of blocking,
 * catching, or ignoring SIGCONT.  When any stop signal is sent, it clears
 * any pending/queued SIGCONT signals; this happens regardless of blocking,
 * catching, or ignored the stop signal, though (except for SIGSTOP) the
 * default action of stopping the process may happen later or never.
 */

#ifdef SIGEMT
#define SIGEMT_MASK	rt_sigmask(SIGEMT)
#else
#define SIGEMT_MASK	0
#endif

#if SIGRTMIN > BITS_PER_LONG
#define rt_sigmask(sig)	(1ULL << ((sig)-1))
#else
#define rt_sigmask(sig)	sigmask(sig)
#endif

#define siginmask(sig, mask) \
	((sig) < SIGRTMIN && (rt_sigmask(sig) & (mask)))

#define SIG_KERNEL_ONLY_MASK (\
	rt_sigmask(SIGKILL)   |  rt_sigmask(SIGSTOP))

#define SIG_KERNEL_STOP_MASK (\
	rt_sigmask(SIGSTOP)   |  rt_sigmask(SIGTSTP)   | \
	rt_sigmask(SIGTTIN)   |  rt_sigmask(SIGTTOU)   )

#define SIG_KERNEL_COREDUMP_MASK (\
        rt_sigmask(SIGQUIT)   |  rt_sigmask(SIGILL)    | \
	rt_sigmask(SIGTRAP)   |  rt_sigmask(SIGABRT)   | \
        rt_sigmask(SIGFPE)    |  rt_sigmask(SIGSEGV)   | \
	rt_sigmask(SIGBUS)    |  rt_sigmask(SIGSYS)    | \
        rt_sigmask(SIGXCPU)   |  rt_sigmask(SIGXFSZ)   | \
	SIGEMT_MASK				       )

#define SIG_KERNEL_IGNORE_MASK (\
        rt_sigmask(SIGCONT)   |  rt_sigmask(SIGCHLD)   | \
	rt_sigmask(SIGWINCH)  |  rt_sigmask(SIGURG)    )

#define sig_kernel_only(sig)		siginmask(sig, SIG_KERNEL_ONLY_MASK)
#define sig_kernel_coredump(sig)	siginmask(sig, SIG_KERNEL_COREDUMP_MASK)
#define sig_kernel_ignore(sig)		siginmask(sig, SIG_KERNEL_IGNORE_MASK)
#define sig_kernel_stop(sig)		siginmask(sig, SIG_KERNEL_STOP_MASK)

#define sig_user_defined(t, signr) \
	(((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_DFL) &&	\
	 ((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_IGN))

#define sig_fatal(t, signr) \
	(!siginmask(signr, SIG_KERNEL_IGNORE_MASK|SIG_KERNEL_STOP_MASK) && \
	 (t)->sighand->action[(signr)-1].sa.sa_handler == SIG_DFL)

void signals_init(void);

int restore_altstack(const stack_t __user *);
int __save_altstack(stack_t __user *, unsigned long);

#define save_altstack_ex(uss, sp) do { \
	stack_t __user *__uss = uss; \
	struct task_struct *t = current; \
	put_user_ex((void __user *)t->sas_ss_sp, &__uss->ss_sp); \
	put_user_ex(t->sas_ss_flags, &__uss->ss_flags); \
	put_user_ex(t->sas_ss_size, &__uss->ss_size); \
	if (t->sas_ss_flags & SS_AUTODISARM) \
		sas_ss_reset(t); \
} while (0);

#ifdef CONFIG_PROC_FS
struct seq_file;
extern void render_sigset_t(struct seq_file *, const char *, sigset_t *);
#endif

#endif /* _LINUX_SIGNAL_H */
Commit	Line	Data
	1	#ifndef _LINUX_SIGNAL_H
	2	#define _LINUX_SIGNAL_H
	3
	4	#include <linux/list.h>
	5	#include <linux/bug.h>
	6	#include <uapi/linux/signal.h>
	7
	8	struct task_struct;
	9
	10	/* for sysctl */
	11	extern int print_fatal_signals;
	12	/*
	13	* Real Time signals may be queued.
	14	*/
	15
	16	struct sigqueue {
	17	struct list_head list;
	18	int flags;
	19	siginfo_t info;
	20	struct user_struct *user;
	21	};
	22
	23	/* flags values. */
	24	#define SIGQUEUE_PREALLOC 1
	25
	26	struct sigpending {
	27	struct list_head list;
	28	sigset_t signal;
	29	};
	30
	31	#ifndef HAVE_ARCH_COPY_SIGINFO
	32
	33	#include <linux/string.h>
	34
	35	static inline void copy_siginfo(struct siginfo to, struct siginfo from)
	36	{
	37	if (from->si_code < 0)
	38	memcpy(to, from, sizeof(*to));
	39	else
	40	/* _sigchld is currently the largest know union member */
	41	memcpy(to, from, __ARCH_SI_PREAMBLE_SIZE + sizeof(from->_sifields._sigchld));
	42	}
	43
	44	#endif
	45
	46	/*
	47	* Define some primitives to manipulate sigset_t.
	48	*/
	49
	50	#ifndef __HAVE_ARCH_SIG_BITOPS
	51	#include <linux/bitops.h>
	52
	53	/* We don't use <linux/bitops.h> for these because there is no need to
	54	be atomic. */
	55	static inline void sigaddset(sigset_t *set, int _sig)
	56	{
	57	unsigned long sig = _sig - 1;
	58	if (_NSIG_WORDS == 1)
	59	set->sig[0] \|= 1UL << sig;
	60	else
	61	set->sig[sig / _NSIG_BPW] \|= 1UL << (sig % _NSIG_BPW);
	62	}
	63
	64	static inline void sigdelset(sigset_t *set, int _sig)
	65	{
	66	unsigned long sig = _sig - 1;
	67	if (_NSIG_WORDS == 1)
	68	set->sig[0] &= ~(1UL << sig);
	69	else
	70	set->sig[sig / _NSIG_BPW] &= ~(1UL << (sig % _NSIG_BPW));
	71	}
	72
	73	static inline int sigismember(sigset_t *set, int _sig)
	74	{
	75	unsigned long sig = _sig - 1;
	76	if (_NSIG_WORDS == 1)
	77	return 1 & (set->sig[0] >> sig);
	78	else
	79	return 1 & (set->sig[sig / _NSIG_BPW] >> (sig % _NSIG_BPW));
	80	}
	81
	82	#endif /* __HAVE_ARCH_SIG_BITOPS */
	83
	84	static inline int sigisemptyset(sigset_t *set)
	85	{
	86	switch (_NSIG_WORDS) {
	87	case 4:
	88	return (set->sig[3] \| set->sig[2] \|
	89	set->sig[1] \| set->sig[0]) == 0;
	90	case 2:
	91	return (set->sig[1] \| set->sig[0]) == 0;
	92	case 1:
	93	return set->sig[0] == 0;
	94	default:
	95	BUILD_BUG();
	96	return 0;
	97	}
	98	}
	99
	100	#define sigmask(sig) (1UL << ((sig) - 1))
	101
	102	#ifndef __HAVE_ARCH_SIG_SETOPS
	103	#include <linux/string.h>
	104
	105	#define _SIG_SET_BINOP(name, op) \
	106	static inline void name(sigset_t r, const sigset_t a, const sigset_t *b) \
	107	{ \
	108	unsigned long a0, a1, a2, a3, b0, b1, b2, b3; \
	109	\
	110	switch (_NSIG_WORDS) { \
	111	case 4: \
	112	a3 = a->sig[3]; a2 = a->sig[2]; \
	113	b3 = b->sig[3]; b2 = b->sig[2]; \
	114	r->sig[3] = op(a3, b3); \
	115	r->sig[2] = op(a2, b2); \
	116	case 2: \
	117	a1 = a->sig[1]; b1 = b->sig[1]; \
	118	r->sig[1] = op(a1, b1); \
	119	case 1: \
	120	a0 = a->sig[0]; b0 = b->sig[0]; \
	121	r->sig[0] = op(a0, b0); \
	122	break; \
	123	default: \
	124	BUILD_BUG(); \
	125	} \
	126	}
	127
	128	#define _sig_or(x,y) ((x) \| (y))
	129	_SIG_SET_BINOP(sigorsets, _sig_or)
	130
	131	#define _sig_and(x,y) ((x) & (y))
	132	_SIG_SET_BINOP(sigandsets, _sig_and)
	133
	134	#define _sig_andn(x,y) ((x) & ~(y))
	135	_SIG_SET_BINOP(sigandnsets, _sig_andn)
	136
	137	#undef _SIG_SET_BINOP
	138	#undef _sig_or
	139	#undef _sig_and
	140	#undef _sig_andn
	141
	142	#define _SIG_SET_OP(name, op) \
	143	static inline void name(sigset_t *set) \
	144	{ \
	145	switch (_NSIG_WORDS) { \
	146	case 4: set->sig[3] = op(set->sig[3]); \
	147	set->sig[2] = op(set->sig[2]); \
	148	case 2: set->sig[1] = op(set->sig[1]); \
	149	case 1: set->sig[0] = op(set->sig[0]); \
	150	break; \
	151	default: \
	152	BUILD_BUG(); \
	153	} \
	154	}
	155
	156	#define _sig_not(x) (~(x))
	157	_SIG_SET_OP(signotset, _sig_not)
	158
	159	#undef _SIG_SET_OP
	160	#undef _sig_not
	161
	162	static inline void sigemptyset(sigset_t *set)
	163	{
	164	switch (_NSIG_WORDS) {
	165	default:
	166	memset(set, 0, sizeof(sigset_t));
	167	break;
	168	case 2: set->sig[1] = 0;
	169	case 1: set->sig[0] = 0;
	170	break;
	171	}
	172	}
	173
	174	static inline void sigfillset(sigset_t *set)
	175	{
	176	switch (_NSIG_WORDS) {
	177	default:
	178	memset(set, -1, sizeof(sigset_t));
	179	break;
	180	case 2: set->sig[1] = -1;
	181	case 1: set->sig[0] = -1;
	182	break;
	183	}
	184	}
	185
	186	/* Some extensions for manipulating the low 32 signals in particular. */
	187
	188	static inline void sigaddsetmask(sigset_t *set, unsigned long mask)
	189	{
	190	set->sig[0] \|= mask;
	191	}
	192
	193	static inline void sigdelsetmask(sigset_t *set, unsigned long mask)
	194	{
	195	set->sig[0] &= ~mask;
	196	}
	197
	198	static inline int sigtestsetmask(sigset_t *set, unsigned long mask)
	199	{
	200	return (set->sig[0] & mask) != 0;
	201	}
	202
	203	static inline void siginitset(sigset_t *set, unsigned long mask)
	204	{
	205	set->sig[0] = mask;
	206	switch (_NSIG_WORDS) {
	207	default:
	208	memset(&set->sig[1], 0, sizeof(long)*(_NSIG_WORDS-1));
	209	break;
	210	case 2: set->sig[1] = 0;
	211	case 1: ;
	212	}
	213	}
	214
	215	static inline void siginitsetinv(sigset_t *set, unsigned long mask)
	216	{
	217	set->sig[0] = ~mask;
	218	switch (_NSIG_WORDS) {
	219	default:
	220	memset(&set->sig[1], -1, sizeof(long)*(_NSIG_WORDS-1));
	221	break;
	222	case 2: set->sig[1] = -1;
	223	case 1: ;
	224	}
	225	}
	226
	227	#endif /* __HAVE_ARCH_SIG_SETOPS */
	228
	229	static inline void init_sigpending(struct sigpending *sig)
	230	{
	231	sigemptyset(&sig->signal);
	232	INIT_LIST_HEAD(&sig->list);
	233	}
	234
	235	extern void flush_sigqueue(struct sigpending *queue);
	236
	237	/* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
	238	static inline int valid_signal(unsigned long sig)
	239	{
	240	return sig <= _NSIG ? 1 : 0;
	241	}
	242
	243	struct timespec;
	244	struct pt_regs;
	245
	246	extern int next_signal(struct sigpending pending, sigset_t mask);
	247	extern int do_send_sig_info(int sig, struct siginfo *info,
	248	struct task_struct *p, bool group);
	249	extern int group_send_sig_info(int sig, struct siginfo info, struct task_struct p);
	250	extern int __group_send_sig_info(int, struct siginfo , struct task_struct );
	251	extern int do_sigtimedwait(const sigset_t , siginfo_t ,
	252	const struct timespec *);
	253	extern int sigprocmask(int, sigset_t , sigset_t );
	254	extern void set_current_blocked(sigset_t *);
	255	extern void __set_current_blocked(const sigset_t *);
	256	extern int show_unhandled_signals;
	257
	258	struct sigaction {
	259	#ifndef __ARCH_HAS_IRIX_SIGACTION
	260	__sighandler_t sa_handler;
	261	unsigned long sa_flags;
	262	#else
	263	unsigned int sa_flags;
	264	__sighandler_t sa_handler;
	265	#endif
	266	#ifdef __ARCH_HAS_SA_RESTORER
	267	__sigrestore_t sa_restorer;
	268	#endif
	269	sigset_t sa_mask; /* mask last for extensibility */
	270	};
	271
	272	struct k_sigaction {
	273	struct sigaction sa;
	274	#ifdef __ARCH_HAS_KA_RESTORER
	275	__sigrestore_t ka_restorer;
	276	#endif
	277	};
	278
	279	#ifdef CONFIG_OLD_SIGACTION
	280	struct old_sigaction {
	281	__sighandler_t sa_handler;
	282	old_sigset_t sa_mask;
	283	unsigned long sa_flags;
	284	__sigrestore_t sa_restorer;
	285	};
	286	#endif
	287
	288	struct ksignal {
	289	struct k_sigaction ka;
	290	siginfo_t info;
	291	int sig;
	292	};
	293
	294	extern int get_signal(struct ksignal *ksig);
	295	extern void signal_setup_done(int failed, struct ksignal *ksig, int stepping);
	296	extern void exit_signals(struct task_struct *tsk);
	297	extern void kernel_sigaction(int, __sighandler_t);
	298
	299	static inline void allow_signal(int sig)
	300	{
	301	/*
	302	* Kernel threads handle their own signals. Let the signal code
	303	* know it'll be handled, so that they don't get converted to
	304	* SIGKILL or just silently dropped.
	305	*/
	306	kernel_sigaction(sig, (__force __sighandler_t)2);
	307	}
	308
	309	static inline void disallow_signal(int sig)
	310	{
	311	kernel_sigaction(sig, SIG_IGN);
	312	}
	313
	314	extern struct kmem_cache *sighand_cachep;
	315
	316	int unhandled_signal(struct task_struct *tsk, int sig);
	317
	318	/*
	319	* In POSIX a signal is sent either to a specific thread (Linux task)
	320	* or to the process as a whole (Linux thread group). How the signal
	321	* is sent determines whether it's to one thread or the whole group,
	322	* which determines which signal mask(s) are involved in blocking it
	323	* from being delivered until later. When the signal is delivered,
	324	* either it's caught or ignored by a user handler or it has a default
	325	* effect that applies to the whole thread group (POSIX process).
	326	*
	327	* The possible effects an unblocked signal set to SIG_DFL can have are:
	328	* ignore - Nothing Happens
	329	* terminate - kill the process, i.e. all threads in the group,
	330	* similar to exit_group. The group leader (only) reports
	331	* WIFSIGNALED status to its parent.
	332	* coredump - write a core dump file describing all threads using
	333	* the same mm and then kill all those threads
	334	* stop - stop all the threads in the group, i.e. TASK_STOPPED state
	335	*
	336	* SIGKILL and SIGSTOP cannot be caught, blocked, or ignored.
	337	* Other signals when not blocked and set to SIG_DFL behaves as follows.
	338	* The job control signals also have other special effects.
	339	*
	340	* +--------------------+------------------+
	341	* \| POSIX signal \| default action \|
	342	* +--------------------+------------------+
	343	* \| SIGHUP \| terminate \|
	344	* \| SIGINT \| terminate \|
	345	* \| SIGQUIT \| coredump \|
	346	* \| SIGILL \| coredump \|
	347	* \| SIGTRAP \| coredump \|
	348	* \| SIGABRT/SIGIOT \| coredump \|
	349	* \| SIGBUS \| coredump \|
	350	* \| SIGFPE \| coredump \|
	351	* \| SIGKILL \| terminate(+) \|
	352	* \| SIGUSR1 \| terminate \|
	353	* \| SIGSEGV \| coredump \|
	354	* \| SIGUSR2 \| terminate \|
	355	* \| SIGPIPE \| terminate \|
	356	* \| SIGALRM \| terminate \|
	357	* \| SIGTERM \| terminate \|
	358	* \| SIGCHLD \| ignore \|
	359	* \| SIGCONT \| ignore(*) \|
	360	* \| SIGSTOP \| stop(*)(+) \|
	361	* \| SIGTSTP \| stop(*) \|
	362	* \| SIGTTIN \| stop(*) \|
	363	* \| SIGTTOU \| stop(*) \|
	364	* \| SIGURG \| ignore \|
	365	* \| SIGXCPU \| coredump \|
	366	* \| SIGXFSZ \| coredump \|
	367	* \| SIGVTALRM \| terminate \|
	368	* \| SIGPROF \| terminate \|
	369	* \| SIGPOLL/SIGIO \| terminate \|
	370	* \| SIGSYS/SIGUNUSED \| coredump \|
	371	* \| SIGSTKFLT \| terminate \|
	372	* \| SIGWINCH \| ignore \|
	373	* \| SIGPWR \| terminate \|
	374	* \| SIGRTMIN-SIGRTMAX \| terminate \|
	375	* +--------------------+------------------+
	376	* \| non-POSIX signal \| default action \|
	377	* +--------------------+------------------+
	378	* \| SIGEMT \| coredump \|
	379	* +--------------------+------------------+
	380	*
	381	* (+) For SIGKILL and SIGSTOP the action is "always", not just "default".
	382	* (*) Special job control effects:
	383	* When SIGCONT is sent, it resumes the process (all threads in the group)
	384	* from TASK_STOPPED state and also clears any pending/queued stop signals
	385	* (any of those marked with "stop(*)"). This happens regardless of blocking,
	386	* catching, or ignoring SIGCONT. When any stop signal is sent, it clears
	387	* any pending/queued SIGCONT signals; this happens regardless of blocking,
	388	* catching, or ignored the stop signal, though (except for SIGSTOP) the
	389	* default action of stopping the process may happen later or never.
	390	*/
	391
	392	#ifdef SIGEMT
	393	#define SIGEMT_MASK rt_sigmask(SIGEMT)
	394	#else
	395	#define SIGEMT_MASK 0
	396	#endif
	397
	398	#if SIGRTMIN > BITS_PER_LONG
	399	#define rt_sigmask(sig) (1ULL << ((sig)-1))
	400	#else
	401	#define rt_sigmask(sig) sigmask(sig)
	402	#endif
	403
	404	#define siginmask(sig, mask) \
	405	((sig) < SIGRTMIN && (rt_sigmask(sig) & (mask)))
	406
	407	#define SIG_KERNEL_ONLY_MASK (\
	408	rt_sigmask(SIGKILL) \| rt_sigmask(SIGSTOP))
	409
	410	#define SIG_KERNEL_STOP_MASK (\
	411	rt_sigmask(SIGSTOP) \| rt_sigmask(SIGTSTP) \| \
	412	rt_sigmask(SIGTTIN) \| rt_sigmask(SIGTTOU) )
	413
	414	#define SIG_KERNEL_COREDUMP_MASK (\
	415	rt_sigmask(SIGQUIT) \| rt_sigmask(SIGILL) \| \
	416	rt_sigmask(SIGTRAP) \| rt_sigmask(SIGABRT) \| \
	417	rt_sigmask(SIGFPE) \| rt_sigmask(SIGSEGV) \| \
	418	rt_sigmask(SIGBUS) \| rt_sigmask(SIGSYS) \| \
	419	rt_sigmask(SIGXCPU) \| rt_sigmask(SIGXFSZ) \| \
	420	SIGEMT_MASK )
	421
	422	#define SIG_KERNEL_IGNORE_MASK (\
	423	rt_sigmask(SIGCONT) \| rt_sigmask(SIGCHLD) \| \
	424	rt_sigmask(SIGWINCH) \| rt_sigmask(SIGURG) )
	425
	426	#define sig_kernel_only(sig) siginmask(sig, SIG_KERNEL_ONLY_MASK)
	427	#define sig_kernel_coredump(sig) siginmask(sig, SIG_KERNEL_COREDUMP_MASK)
	428	#define sig_kernel_ignore(sig) siginmask(sig, SIG_KERNEL_IGNORE_MASK)
	429	#define sig_kernel_stop(sig) siginmask(sig, SIG_KERNEL_STOP_MASK)
	430
	431	#define sig_user_defined(t, signr) \
	432	(((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_DFL) && \
	433	((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_IGN))
	434
	435	#define sig_fatal(t, signr) \
	436	(!siginmask(signr, SIG_KERNEL_IGNORE_MASK\|SIG_KERNEL_STOP_MASK) && \
	437	(t)->sighand->action[(signr)-1].sa.sa_handler == SIG_DFL)
	438
	439	void signals_init(void);
	440
	441	int restore_altstack(const stack_t __user *);
	442	int __save_altstack(stack_t __user *, unsigned long);
	443
	444	#define save_altstack_ex(uss, sp) do { \
	445	stack_t __user *__uss = uss; \
	446	struct task_struct *t = current; \
	447	put_user_ex((void __user *)t->sas_ss_sp, &__uss->ss_sp); \
	448	put_user_ex(t->sas_ss_flags, &__uss->ss_flags); \
	449	put_user_ex(t->sas_ss_size, &__uss->ss_size); \
	450	if (t->sas_ss_flags & SS_AUTODISARM) \
	451	sas_ss_reset(t); \
	452	} while (0);
	453
	454	#ifdef CONFIG_PROC_FS
	455	struct seq_file;
	456	extern void render_sigset_t(struct seq_file , const char , sigset_t *);
	457	#endif
	458
	459	#endif /* _LINUX_SIGNAL_H */