blob: 44348ca5a70738ab4033b68d66c97bdcaa626495 [file] [log] [blame]
* linux/ipc/util.h
* Copyright (C) 1999 Christoph Rohland
* ipc helper functions (c) 1999 Manfred Spraul <>
#ifndef _IPC_UTIL_H
#define _IPC_UTIL_H
#define USHRT_MAX 0xffff
void sem_init (void);
void msg_init (void);
void shm_init (void);
struct ipc_id_ary {
int size;
struct kern_ipc_perm *p[0];
struct ipc_ids {
int in_use;
int max_id;
unsigned short seq;
unsigned short seq_max;
struct semaphore sem;
struct ipc_id_ary nullentry;
struct ipc_id_ary* entries;
void __init ipc_init_ids(struct ipc_ids* ids, int size);
/* must be called with ids->sem acquired.*/
int ipc_findkey(struct ipc_ids* ids, key_t key);
int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size);
/* must be called with both locks acquired. */
struct kern_ipc_perm* ipc_rmid(struct ipc_ids* ids, int id);
int ipcperms (struct kern_ipc_perm *ipcp, short flg);
/* for rare, potentially huge allocations.
* both function can sleep
void* ipc_alloc(int size);
void ipc_free(void* ptr, int size);
* For allocation that need to be freed by RCU.
* Objects are reference counted, they start with reference count 1.
* getref increases the refcount, the putref call that reduces the recount
* to 0 schedules the rcu destruction. Caller must guarantee locking.
void* ipc_rcu_alloc(int size);
void ipc_rcu_getref(void *ptr);
void ipc_rcu_putref(void *ptr);
struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id);
struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id);
void ipc_lock_by_ptr(struct kern_ipc_perm *ipcp);
void ipc_unlock(struct kern_ipc_perm* perm);
int ipc_buildid(struct ipc_ids* ids, int id, int seq);
int ipc_checkid(struct ipc_ids* ids, struct kern_ipc_perm* ipcp, int uid);
void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out);
void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out);
#if defined(__ia64__) || defined(__x86_64__) || defined(__hppa__) || defined(__XTENSA__)
/* On IA-64, we always use the "64-bit version" of the IPC structures. */
# define ipc_parse_version(cmd) IPC_64
int ipc_parse_version (int *cmd);
extern void free_msg(struct msg_msg *msg);
extern struct msg_msg *load_msg(const void __user *src, int len);
extern int store_msg(void __user *dest, struct msg_msg *msg, int len);