Linux kernel mirror (for testing)
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linux
1/*
2 * linux/ipc/util.h
3 * Copyright (C) 1999 Christoph Rohland
4 *
5 * ipc helper functions (c) 1999 Manfred Spraul <manfreds@colorfullife.com>
6 */
7
8#ifndef _IPC_UTIL_H
9#define _IPC_UTIL_H
10
11#define USHRT_MAX 0xffff
12#define SEQ_MULTIPLIER (IPCMNI)
13
14void sem_init (void);
15void msg_init (void);
16void shm_init (void);
17
18struct ipc_id_ary {
19 int size;
20 struct kern_ipc_perm *p[0];
21};
22
23struct ipc_ids {
24 int in_use;
25 int max_id;
26 unsigned short seq;
27 unsigned short seq_max;
28 struct semaphore sem;
29 struct ipc_id_ary nullentry;
30 struct ipc_id_ary* entries;
31};
32
33void __init ipc_init_ids(struct ipc_ids* ids, int size);
34
35/* must be called with ids->sem acquired.*/
36int ipc_findkey(struct ipc_ids* ids, key_t key);
37int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size);
38
39/* must be called with both locks acquired. */
40struct kern_ipc_perm* ipc_rmid(struct ipc_ids* ids, int id);
41
42int ipcperms (struct kern_ipc_perm *ipcp, short flg);
43
44/* for rare, potentially huge allocations.
45 * both function can sleep
46 */
47void* ipc_alloc(int size);
48void ipc_free(void* ptr, int size);
49
50/*
51 * For allocation that need to be freed by RCU.
52 * Objects are reference counted, they start with reference count 1.
53 * getref increases the refcount, the putref call that reduces the recount
54 * to 0 schedules the rcu destruction. Caller must guarantee locking.
55 */
56void* ipc_rcu_alloc(int size);
57void ipc_rcu_getref(void *ptr);
58void ipc_rcu_putref(void *ptr);
59
60struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id);
61struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id);
62void ipc_lock_by_ptr(struct kern_ipc_perm *ipcp);
63void ipc_unlock(struct kern_ipc_perm* perm);
64int ipc_buildid(struct ipc_ids* ids, int id, int seq);
65int ipc_checkid(struct ipc_ids* ids, struct kern_ipc_perm* ipcp, int uid);
66
67void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out);
68void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out);
69
70#if defined(__ia64__) || defined(__x86_64__) || defined(__hppa__) || defined(__XTENSA__)
71 /* On IA-64, we always use the "64-bit version" of the IPC structures. */
72# define ipc_parse_version(cmd) IPC_64
73#else
74int ipc_parse_version (int *cmd);
75#endif
76
77extern void free_msg(struct msg_msg *msg);
78extern struct msg_msg *load_msg(const void __user *src, int len);
79extern int store_msg(void __user *dest, struct msg_msg *msg, int len);
80
81#endif