1#ifndef _LINUX_SEM_H
2#define _LINUX_SEM_H
3
4#include <linux/atomic.h>
5#include <linux/rcupdate.h>
6#include <linux/cache.h>
7#include <uapi/linux/sem.h>
8
9struct task_struct;
10
11/* One sem_array data structure for each set of semaphores in the system. */
12struct sem_array {
13	struct kern_ipc_perm	____cacheline_aligned_in_smp
14				sem_perm;	/* permissions .. see ipc.h */
15	time_t			sem_ctime;	/* last change time */
16	struct sem		*sem_base;	/* ptr to first semaphore in array */
17	struct list_head	pending_alter;	/* pending operations */
18						/* that alter the array */
19	struct list_head	pending_const;	/* pending complex operations */
20						/* that do not alter semvals */
21	struct list_head	list_id;	/* undo requests on this array */
22	int			sem_nsems;	/* no. of semaphores in array */
23	int			complex_count;	/* pending complex operations */
24};
25
26#ifdef CONFIG_SYSVIPC
27
28struct sysv_sem {
29	struct sem_undo_list *undo_list;
30};
31
32extern int copy_semundo(unsigned long clone_flags, struct task_struct *tsk);
33extern void exit_sem(struct task_struct *tsk);
34
35#else
36
37struct sysv_sem {
38	/* empty */
39};
40
41static inline int copy_semundo(unsigned long clone_flags, struct task_struct *tsk)
42{
43	return 0;
44}
45
46static inline void exit_sem(struct task_struct *tsk)
47{
48	return;
49}
50#endif
51
52#endif /* _LINUX_SEM_H */
53