Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _UAPI_LINUX_SEM_H
3#define _UAPI_LINUX_SEM_H
4
5#include <linux/ipc.h>
6
7/* semop flags */
8#define SEM_UNDO 0x1000 /* undo the operation on exit */
9
10/* semctl Command Definitions. */
11#define GETPID 11 /* get sempid */
12#define GETVAL 12 /* get semval */
13#define GETALL 13 /* get all semval's */
14#define GETNCNT 14 /* get semncnt */
15#define GETZCNT 15 /* get semzcnt */
16#define SETVAL 16 /* set semval */
17#define SETALL 17 /* set all semval's */
18
19/* ipcs ctl cmds */
20#define SEM_STAT 18
21#define SEM_INFO 19
22
23/* Obsolete, used only for backwards compatibility and libc5 compiles */
24struct semid_ds {
25 struct ipc_perm sem_perm; /* permissions .. see ipc.h */
26 __kernel_time_t sem_otime; /* last semop time */
27 __kernel_time_t sem_ctime; /* create/last semctl() time */
28 struct sem *sem_base; /* ptr to first semaphore in array */
29 struct sem_queue *sem_pending; /* pending operations to be processed */
30 struct sem_queue **sem_pending_last; /* last pending operation */
31 struct sem_undo *undo; /* undo requests on this array */
32 unsigned short sem_nsems; /* no. of semaphores in array */
33};
34
35/* Include the definition of semid64_ds */
36#include <asm/sembuf.h>
37
38/* semop system calls takes an array of these. */
39struct sembuf {
40 unsigned short sem_num; /* semaphore index in array */
41 short sem_op; /* semaphore operation */
42 short sem_flg; /* operation flags */
43};
44
45/* arg for semctl system calls. */
46union semun {
47 int val; /* value for SETVAL */
48 struct semid_ds __user *buf; /* buffer for IPC_STAT & IPC_SET */
49 unsigned short __user *array; /* array for GETALL & SETALL */
50 struct seminfo __user *__buf; /* buffer for IPC_INFO */
51 void __user *__pad;
52};
53
54struct seminfo {
55 int semmap;
56 int semmni;
57 int semmns;
58 int semmnu;
59 int semmsl;
60 int semopm;
61 int semume;
62 int semusz;
63 int semvmx;
64 int semaem;
65};
66
67/*
68 * SEMMNI, SEMMSL and SEMMNS are default values which can be
69 * modified by sysctl.
70 * The values has been chosen to be larger than necessary for any
71 * known configuration.
72 *
73 * SEMOPM should not be increased beyond 1000, otherwise there is the
74 * risk that semop()/semtimedop() fails due to kernel memory fragmentation when
75 * allocating the sop array.
76 */
77
78
79#define SEMMNI 32000 /* <= IPCMNI max # of semaphore identifiers */
80#define SEMMSL 32000 /* <= INT_MAX max num of semaphores per id */
81#define SEMMNS (SEMMNI*SEMMSL) /* <= INT_MAX max # of semaphores in system */
82#define SEMOPM 500 /* <= 1 000 max num of ops per semop call */
83#define SEMVMX 32767 /* <= 32767 semaphore maximum value */
84#define SEMAEM SEMVMX /* adjust on exit max value */
85
86/* unused */
87#define SEMUME SEMOPM /* max num of undo entries per process */
88#define SEMMNU SEMMNS /* num of undo structures system wide */
89#define SEMMAP SEMMNS /* # of entries in semaphore map */
90#define SEMUSZ 20 /* sizeof struct sem_undo */
91
92
93#endif /* _UAPI_LINUX_SEM_H */