| /* |
| * linux/ipc/util.h |
| * Copyright (C) 1999 Christoph Rohland |
| * |
| * ipc helper functions (c) 1999 Manfred Spraul <manfreds@colorfullife.com> |
| */ |
| |
| #define USHRT_MAX 0xffff |
| #define SEQ_MULTIPLIER (IPCMNI) |
| |
| void sem_init (void); |
| void msg_init (void); |
| void shm_init (void); |
| |
| struct ipc_ids { |
| int size; |
| int in_use; |
| int max_id; |
| unsigned short seq; |
| unsigned short seq_max; |
| struct semaphore sem; |
| spinlock_t ary; |
| struct ipc_id* entries; |
| }; |
| |
| struct ipc_id { |
| struct kern_ipc_perm* p; |
| }; |
| |
| |
| 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); |
| |
| extern inline void ipc_lockall(struct ipc_ids* ids) |
| { |
| spin_lock(&ids->ary); |
| } |
| |
| extern inline struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id) |
| { |
| struct kern_ipc_perm* out; |
| int lid = id % SEQ_MULTIPLIER; |
| if(lid >= ids->size) |
| return NULL; |
| |
| out = ids->entries[lid].p; |
| return out; |
| } |
| |
| extern inline void ipc_unlockall(struct ipc_ids* ids) |
| { |
| spin_unlock(&ids->ary); |
| } |
| extern inline struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id) |
| { |
| struct kern_ipc_perm* out; |
| int lid = id % SEQ_MULTIPLIER; |
| if(lid >= ids->size) |
| return NULL; |
| |
| spin_lock(&ids->ary); |
| out = ids->entries[lid].p; |
| if(out==NULL) |
| spin_unlock(&ids->ary); |
| return out; |
| } |
| |
| extern inline void ipc_unlock(struct ipc_ids* ids, int id) |
| { |
| spin_unlock(&ids->ary); |
| } |
| |
| extern inline int ipc_buildid(struct ipc_ids* ids, int id, int seq) |
| { |
| return SEQ_MULTIPLIER*seq + id; |
| } |
| |
| extern inline int ipc_checkid(struct ipc_ids* ids, struct kern_ipc_perm* ipcp, int uid) |
| { |
| if(uid/SEQ_MULTIPLIER != ipcp->seq) |
| return 1; |
| return 0; |
| } |
| |
| 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); |
| |
| #ifdef __ia64__ |
| /* On IA-64, we always use the "64-bit version" of the IPC structures. */ |
| # define ipc_parse_version(cmd) IPC_64 |
| #else |
| int ipc_parse_version (int *cmd); |
| #endif |