sem.h (3050B) - Raw
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 #ifndef _LINUX_SEM_H 3 #define _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 #define SEM_STAT_ANY 20 23 24 /* Obsolete, used only for backwards compatibility and libc5 compiles */ 25 struct semid_ds { 26 struct ipc_perm sem_perm; /* permissions .. see ipc.h */ 27 __kernel_old_time_t sem_otime; /* last semop time */ 28 __kernel_old_time_t sem_ctime; /* create/last semctl() time */ 29 struct sem *sem_base; /* ptr to first semaphore in array */ 30 struct sem_queue *sem_pending; /* pending operations to be processed */ 31 struct sem_queue **sem_pending_last; /* last pending operation */ 32 struct sem_undo *undo; /* undo requests on this array */ 33 unsigned short sem_nsems; /* no. of semaphores in array */ 34 }; 35 36 /* Include the definition of semid64_ds */ 37 #include <asm/sembuf.h> 38 39 /* semop system calls takes an array of these. */ 40 struct sembuf { 41 unsigned short sem_num; /* semaphore index in array */ 42 short sem_op; /* semaphore operation */ 43 short sem_flg; /* operation flags */ 44 }; 45 46 /* arg for semctl system calls. */ 47 union semun { 48 int val; /* value for SETVAL */ 49 struct semid_ds *buf; /* buffer for IPC_STAT & IPC_SET */ 50 unsigned short *array; /* array for GETALL & SETALL */ 51 struct seminfo *__buf; /* buffer for IPC_INFO */ 52 void *__pad; 53 }; 54 55 struct seminfo { 56 int semmap; 57 int semmni; 58 int semmns; 59 int semmnu; 60 int semmsl; 61 int semopm; 62 int semume; 63 int semusz; 64 int semvmx; 65 int semaem; 66 }; 67 68 /* 69 * SEMMNI, SEMMSL and SEMMNS are default values which can be 70 * modified by sysctl. 71 * The values has been chosen to be larger than necessary for any 72 * known configuration. 73 * 74 * SEMOPM should not be increased beyond 1000, otherwise there is the 75 * risk that semop()/semtimedop() fails due to kernel memory fragmentation when 76 * allocating the sop array. 77 */ 78 79 80 #define SEMMNI 32000 /* <= IPCMNI max # of semaphore identifiers */ 81 #define SEMMSL 32000 /* <= INT_MAX max num of semaphores per id */ 82 #define SEMMNS (SEMMNI*SEMMSL) /* <= INT_MAX max # of semaphores in system */ 83 #define SEMOPM 500 /* <= 1 000 max num of ops per semop call */ 84 #define SEMVMX 32767 /* <= 32767 semaphore maximum value */ 85 #define SEMAEM SEMVMX /* adjust on exit max value */ 86 87 /* unused */ 88 #define SEMUME SEMOPM /* max num of undo entries per process */ 89 #define SEMMNU SEMMNS /* num of undo structures system wide */ 90 #define SEMMAP SEMMNS /* # of entries in semaphore map */ 91 #define SEMUSZ 20 /* sizeof struct sem_undo */ 92 93 94 #endif /* _LINUX_SEM_H */