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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 */ | |
24 | struct 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. */ | |
39 | struct 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. */ | |
46 | union 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 | ||
54 | struct 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. */ | |
83 | struct 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. */ | |
89 | struct sem_array { | |
90 | struct kern_ipc_perm sem_perm; /* permissions .. see ipc.h */ | |
19b4946c | 91 | int sem_id; |
1da177e4 LT |
92 | time_t sem_otime; /* last semop time */ |
93 | time_t sem_ctime; /* last change time */ | |
94 | struct sem *sem_base; /* ptr to first semaphore in array */ | |
95 | struct sem_queue *sem_pending; /* pending operations to be processed */ | |
96 | struct sem_queue **sem_pending_last; /* last pending operation */ | |
97 | struct sem_undo *undo; /* undo requests on this array */ | |
98 | unsigned long sem_nsems; /* no. of semaphores in array */ | |
99 | }; | |
100 | ||
101 | /* One queue for each sleeping process in the system. */ | |
102 | struct sem_queue { | |
103 | struct sem_queue * next; /* next entry in the queue */ | |
104 | struct sem_queue ** prev; /* previous entry in the queue, *(q->prev) == q */ | |
105 | struct task_struct* sleeper; /* this process */ | |
106 | struct sem_undo * undo; /* undo structure */ | |
107 | int pid; /* process id of requesting process */ | |
108 | int status; /* completion status of operation */ | |
109 | struct sem_array * sma; /* semaphore array for operations */ | |
110 | int id; /* internal sem id */ | |
111 | struct sembuf * sops; /* array of pending operations */ | |
112 | int nsops; /* number of operations */ | |
113 | int alter; /* does the operation alter the array? */ | |
114 | }; | |
115 | ||
116 | /* Each task has a list of undo requests. They are executed automatically | |
117 | * when the process exits. | |
118 | */ | |
119 | struct sem_undo { | |
120 | struct sem_undo * proc_next; /* next entry on this process */ | |
121 | struct sem_undo * id_next; /* next entry on this semaphore set */ | |
122 | int semid; /* semaphore set identifier */ | |
123 | short * semadj; /* array of adjustments, one per semaphore */ | |
124 | }; | |
125 | ||
126 | /* sem_undo_list controls shared access to the list of sem_undo structures | |
127 | * that may be shared among all a CLONE_SYSVSEM task group. | |
128 | */ | |
129 | struct sem_undo_list { | |
130 | atomic_t refcnt; | |
131 | spinlock_t lock; | |
132 | struct sem_undo *proc_list; | |
133 | }; | |
134 | ||
135 | struct sysv_sem { | |
136 | struct sem_undo_list *undo_list; | |
137 | }; | |
138 | ||
139 | #ifdef CONFIG_SYSVIPC | |
140 | ||
141 | extern int copy_semundo(unsigned long clone_flags, struct task_struct *tsk); | |
142 | extern void exit_sem(struct task_struct *tsk); | |
143 | ||
144 | #else | |
145 | static inline int copy_semundo(unsigned long clone_flags, struct task_struct *tsk) | |
146 | { | |
147 | return 0; | |
148 | } | |
149 | ||
150 | static inline void exit_sem(struct task_struct *tsk) | |
151 | { | |
152 | return; | |
153 | } | |
154 | #endif | |
155 | ||
156 | #endif /* __KERNEL__ */ | |
157 | ||
158 | #endif /* _LINUX_SEM_H */ |