/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef _LINUX_SEM_H #define _LINUX_SEM_H #include <linux/ipc.h> /* semop flags */ #define SEM_UNDO 0x1000 /* undo the operation on exit */ /* semctl Command Definitions. */ #define GETPID 11 /* get sempid */ #define GETVAL 12 /* get semval */ #define GETALL 13 /* get all semval's */ #define GETNCNT 14 /* get semncnt */ #define GETZCNT 15 /* get semzcnt */ #define SETVAL 16 /* set semval */ #define SETALL 17 /* set all semval's */ /* ipcs ctl cmds */ #define SEM_STAT 18 #define SEM_INFO 19 #define SEM_STAT_ANY 20 /* Obsolete, used only for backwards compatibility and libc5 compiles */ struct semid_ds { struct ipc_perm sem_perm; /* permissions .. see ipc.h */ __kernel_old_time_t sem_otime; /* last semop time */ __kernel_old_time_t sem_ctime; /* create/last semctl() time */ struct sem *sem_base; /* ptr to first semaphore in array */ struct sem_queue *sem_pending; /* pending operations to be processed */ struct sem_queue **sem_pending_last; /* last pending operation */ struct sem_undo *undo; /* undo requests on this array */ unsigned short sem_nsems; /* no. of semaphores in array */ }; /* Include the definition of semid64_ds */ #include <asm/sembuf.h> /* semop system calls takes an array of these. */ struct sembuf { unsigned short sem_num; /* semaphore index in array */ short sem_op; /* semaphore operation */ short sem_flg; /* operation flags */ }; /* arg for semctl system calls. */ union semun { int val; /* value for SETVAL */ struct semid_ds *buf; /* buffer for IPC_STAT & IPC_SET */ unsigned short *array; /* array for GETALL & SETALL */ struct seminfo *__buf; /* buffer for IPC_INFO */ void *__pad; }; struct seminfo { int semmap; int semmni; int semmns; int semmnu; int semmsl; int semopm; int semume; int semusz; int semvmx; int semaem; }; /* * SEMMNI, SEMMSL and SEMMNS are default values which can be * modified by sysctl. * The values has been chosen to be larger than necessary for any * known configuration. * * SEMOPM should not be increased beyond 1000, otherwise there is the * risk that semop()/semtimedop() fails due to kernel memory fragmentation when * allocating the sop array. */ #define SEMMNI 32000 /* <= IPCMNI max # of semaphore identifiers */ #define SEMMSL 32000 /* <= INT_MAX max num of semaphores per id */ #define SEMMNS (SEMMNI*SEMMSL) /* <= INT_MAX max # of semaphores in system */ #define SEMOPM 500 /* <= 1 000 max num of ops per semop call */ #define SEMVMX 32767 /* <= 32767 semaphore maximum value */ #define SEMAEM SEMVMX /* adjust on exit max value */ /* unused */ #define SEMUME SEMOPM /* max num of undo entries per process */ #define SEMMNU SEMMNS /* num of undo structures system wide */ #define SEMMAP SEMMNS /* # of entries in semaphore map */ #define SEMUSZ 20 /* sizeof struct sem_undo */ #endif /* _LINUX_SEM_H */