1#ifndef _LINUX_SEM_H 2#define _LINUX_SEM_H 3 4#include <linux/ipc.h> 5#include <asm/atomic.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; /* last change 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#define SEMMNI 128 /* <= IPCMNI max # of semaphore identifiers */ 68#define SEMMSL 250 /* <= 8 000 max num of semaphores per id */ 69#define SEMMNS (SEMMNI*SEMMSL) /* <= INT_MAX max # of semaphores in system */ 70#define SEMOPM 32 /* <= 1 000 max num of ops per semop call */ 71#define SEMVMX 32767 /* <= 32767 semaphore maximum value */ 72#define SEMAEM SEMVMX /* adjust on exit max value */ 73 74/* unused */ 75#define SEMUME SEMOPM /* max num of undo entries per process */ 76#define SEMMNU SEMMNS /* num of undo structures system wide */ 77#define SEMMAP SEMMNS /* # of entries in semaphore map */ 78#define SEMUSZ 20 /* sizeof struct sem_undo */ 79 80#ifdef __KERNEL__ 81 82/* One semaphore structure for each semaphore in the system. */ 83struct sem { 84 int semval; /* current value */ 85 int sempid; /* pid of last operation */ 86}; 87 88/* One sem_array data structure for each set of semaphores in the system. */ 89struct sem_array { 90 struct kern_ipc_perm sem_perm; /* permissions .. see ipc.h */ 91 time_t sem_otime; /* last semop time */ 92 time_t sem_ctime; /* last change time */ 93 struct sem *sem_base; /* ptr to first semaphore in array */ 94 struct sem_queue *sem_pending; /* pending operations to be processed */ 95 struct sem_queue **sem_pending_last; /* last pending operation */ 96 struct sem_undo *undo; /* undo requests on this array */ 97 unsigned long sem_nsems; /* no. of semaphores in array */ 98}; 99 100/* One queue for each sleeping process in the system. */ 101struct sem_queue { 102 struct sem_queue * next; /* next entry in the queue */ 103 struct sem_queue ** prev; /* previous entry in the queue, *(q->prev) == q */ 104 struct task_struct* sleeper; /* this process */ 105 struct sem_undo * undo; /* undo structure */ 106 int pid; /* process id of requesting process */ 107 int status; /* completion status of operation */ 108 struct sem_array * sma; /* semaphore array for operations */ 109 int id; /* internal sem id */ 110 struct sembuf * sops; /* array of pending operations */ 111 int nsops; /* number of operations */ 112 int alter; /* does the operation alter the array? */ 113}; 114 115/* Each task has a list of undo requests. They are executed automatically 116 * when the process exits. 117 */ 118struct sem_undo { 119 struct sem_undo * proc_next; /* next entry on this process */ 120 struct sem_undo * id_next; /* next entry on this semaphore set */ 121 int semid; /* semaphore set identifier */ 122 short * semadj; /* array of adjustments, one per semaphore */ 123}; 124 125/* sem_undo_list controls shared access to the list of sem_undo structures 126 * that may be shared among all a CLONE_SYSVSEM task group. 127 */ 128struct sem_undo_list { 129 atomic_t refcnt; 130 spinlock_t lock; 131 struct sem_undo *proc_list; 132}; 133 134struct sysv_sem { 135 struct sem_undo_list *undo_list; 136}; 137 138#ifdef CONFIG_SYSVIPC 139 140extern int copy_semundo(unsigned long clone_flags, struct task_struct *tsk); 141extern void exit_sem(struct task_struct *tsk); 142 143#else 144static inline int copy_semundo(unsigned long clone_flags, struct task_struct *tsk) 145{ 146 return 0; 147} 148 149static inline void exit_sem(struct task_struct *tsk) 150{ 151 return; 152} 153#endif 154 155#endif /* __KERNEL__ */ 156 157#endif /* _LINUX_SEM_H */ 158