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git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - ipc/util.h
3 * Copyright (C) 1999 Christoph Rohland
5 * ipc helper functions (c) 1999 Manfred Spraul <manfred@colorfullife.com>
6 * namespaces support. 2006 OpenVZ, SWsoft Inc.
7 * Pavel Emelianov <xemul@openvz.org>
13 #include <linux/err.h>
15 #define SEQ_MULTIPLIER (IPCMNI)
23 #ifdef CONFIG_POSIX_MQUEUE
24 void mq_exit_ns(struct ipc_namespace
*ns
);
26 static inline void mq_exit_ns(struct ipc_namespace
*ns
) { }
30 void sem_init_ns(struct ipc_namespace
*ns
);
31 void msg_init_ns(struct ipc_namespace
*ns
);
32 void shm_init_ns(struct ipc_namespace
*ns
);
34 void sem_exit_ns(struct ipc_namespace
*ns
);
35 void msg_exit_ns(struct ipc_namespace
*ns
);
36 void shm_exit_ns(struct ipc_namespace
*ns
);
38 static inline void sem_init_ns(struct ipc_namespace
*ns
) { }
39 static inline void msg_init_ns(struct ipc_namespace
*ns
) { }
40 static inline void shm_init_ns(struct ipc_namespace
*ns
) { }
42 static inline void sem_exit_ns(struct ipc_namespace
*ns
) { }
43 static inline void msg_exit_ns(struct ipc_namespace
*ns
) { }
44 static inline void shm_exit_ns(struct ipc_namespace
*ns
) { }
48 * Structure that holds the parameters needed by the ipc operations
55 size_t size
; /* for shared memories */
56 int nsems
; /* for semaphores */
57 } u
; /* holds the getnew() specific param */
61 * Structure that holds some ipc operations. This structure is used to unify
62 * the calls to sys_msgget(), sys_semget(), sys_shmget()
63 * . routine to call to create a new ipc object. Can be one of newque,
65 * . routine to call to check permissions for a new ipc object.
66 * Can be one of security_msg_associate, security_sem_associate,
67 * security_shm_associate
68 * . routine to call for an extra check if needed
71 int (*getnew
) (struct ipc_namespace
*, struct ipc_params
*);
72 int (*associate
) (struct kern_ipc_perm
*, int);
73 int (*more_checks
) (struct kern_ipc_perm
*, struct ipc_params
*);
79 void ipc_init_ids(struct ipc_ids
*);
81 void __init
ipc_init_proc_interface(const char *path
, const char *header
,
82 int ids
, int (*show
)(struct seq_file
*, void *));
84 #define ipc_init_proc_interface(path, header, ids, show) do {} while (0)
91 #define ipcid_to_idx(id) ((id) % SEQ_MULTIPLIER)
93 /* must be called with ids->rw_mutex acquired for writing */
94 int ipc_addid(struct ipc_ids
*, struct kern_ipc_perm
*, int);
96 /* must be called with ids->rw_mutex acquired for reading */
97 int ipc_get_maxid(struct ipc_ids
*);
99 /* must be called with both locks acquired. */
100 void ipc_rmid(struct ipc_ids
*, struct kern_ipc_perm
*);
102 /* must be called with ipcp locked */
103 int ipcperms(struct kern_ipc_perm
*ipcp
, short flg
);
105 /* for rare, potentially huge allocations.
106 * both function can sleep
108 void* ipc_alloc(int size
);
109 void ipc_free(void* ptr
, int size
);
112 * For allocation that need to be freed by RCU.
113 * Objects are reference counted, they start with reference count 1.
114 * getref increases the refcount, the putref call that reduces the recount
115 * to 0 schedules the rcu destruction. Caller must guarantee locking.
117 void* ipc_rcu_alloc(int size
);
118 void ipc_rcu_getref(void *ptr
);
119 void ipc_rcu_putref(void *ptr
);
121 struct kern_ipc_perm
*ipc_lock(struct ipc_ids
*, int);
123 void kernel_to_ipc64_perm(struct kern_ipc_perm
*in
, struct ipc64_perm
*out
);
124 void ipc64_perm_to_ipc_perm(struct ipc64_perm
*in
, struct ipc_perm
*out
);
125 void ipc_update_perm(struct ipc64_perm
*in
, struct kern_ipc_perm
*out
);
126 struct kern_ipc_perm
*ipcctl_pre_down(struct ipc_ids
*ids
, int id
, int cmd
,
127 struct ipc64_perm
*perm
, int extra_perm
);
129 #if defined(__ia64__) || defined(__x86_64__) || defined(__hppa__) || defined(__XTENSA__)
130 /* On IA-64, we always use the "64-bit version" of the IPC structures. */
131 # define ipc_parse_version(cmd) IPC_64
133 int ipc_parse_version (int *cmd
);
136 extern void free_msg(struct msg_msg
*msg
);
137 extern struct msg_msg
*load_msg(const void __user
*src
, int len
);
138 extern int store_msg(void __user
*dest
, struct msg_msg
*msg
, int len
);
140 extern void recompute_msgmni(struct ipc_namespace
*);
142 static inline int ipc_buildid(int id
, int seq
)
144 return SEQ_MULTIPLIER
* seq
+ id
;
148 * Must be called with ipcp locked
150 static inline int ipc_checkid(struct kern_ipc_perm
*ipcp
, int uid
)
152 if (uid
/ SEQ_MULTIPLIER
!= ipcp
->seq
)
157 static inline void ipc_lock_by_ptr(struct kern_ipc_perm
*perm
)
160 spin_lock(&perm
->lock
);
163 static inline void ipc_unlock(struct kern_ipc_perm
*perm
)
165 spin_unlock(&perm
->lock
);
169 struct kern_ipc_perm
*ipc_lock_check(struct ipc_ids
*ids
, int id
);
170 int ipcget(struct ipc_namespace
*ns
, struct ipc_ids
*ids
,
171 struct ipc_ops
*ops
, struct ipc_params
*params
);