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/idr.h>
15 #define USHRT_MAX 0xffff
16 #define SEQ_MULTIPLIER (IPCMNI)
22 int sem_init_ns(struct ipc_namespace *ns);
23 int msg_init_ns(struct ipc_namespace *ns);
24 int shm_init_ns(struct ipc_namespace *ns);
26 void sem_exit_ns(struct ipc_namespace *ns);
27 void msg_exit_ns(struct ipc_namespace *ns);
28 void shm_exit_ns(struct ipc_namespace *ns);
33 unsigned short seq_max;
39 * Structure that holds the parameters needed by the ipc operations
46 size_t size; /* for shared memories */
47 int nsems; /* for semaphores */
48 } u; /* holds the getnew() specific param */
52 * Structure that holds some ipc operations. This structure is used to unify
53 * the calls to sys_msgget(), sys_semget(), sys_shmget()
54 * . routine to call to create a new ipc object. Can be one of newque,
56 * . routine to call to call to check permissions for a new ipc object.
57 * Can be one of security_msg_associate, security_sem_associate,
58 * security_shm_associate
59 * . routine to call for an extra check if needed
62 int (*getnew) (struct ipc_namespace *, struct ipc_params *);
63 int (*associate) (void *, int);
64 int (*more_checks) (void *, struct ipc_params *);
69 void ipc_init_ids(struct ipc_ids *);
71 void __init ipc_init_proc_interface(const char *path, const char *header,
72 int ids, int (*show)(struct seq_file *, void *));
74 #define ipc_init_proc_interface(path, header, ids, show) do {} while (0)
81 /* must be called with ids->mutex acquired.*/
82 int ipc_addid(struct ipc_ids *, struct kern_ipc_perm *, int);
83 int ipc_get_maxid(struct ipc_ids *);
85 /* must be called with both locks acquired. */
86 void ipc_rmid(struct ipc_ids *, struct kern_ipc_perm *);
88 int ipcperms (struct kern_ipc_perm *ipcp, short flg);
90 /* for rare, potentially huge allocations.
91 * both function can sleep
93 void* ipc_alloc(int size);
94 void ipc_free(void* ptr, int size);
97 * For allocation that need to be freed by RCU.
98 * Objects are reference counted, they start with reference count 1.
99 * getref increases the refcount, the putref call that reduces the recount
100 * to 0 schedules the rcu destruction. Caller must guarantee locking.
102 void* ipc_rcu_alloc(int size);
103 void ipc_rcu_getref(void *ptr);
104 void ipc_rcu_putref(void *ptr);
106 struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id);
107 void ipc_lock_by_ptr(struct kern_ipc_perm *ipcp);
108 void ipc_unlock(struct kern_ipc_perm* perm);
109 int ipc_buildid(struct ipc_ids* ids, int id, int seq);
110 int ipc_checkid(struct ipc_ids* ids, struct kern_ipc_perm* ipcp, int uid);
112 void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out);
113 void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out);
115 #if defined(__ia64__) || defined(__x86_64__) || defined(__hppa__) || defined(__XTENSA__)
116 /* On IA-64, we always use the "64-bit version" of the IPC structures. */
117 # define ipc_parse_version(cmd) IPC_64
119 int ipc_parse_version (int *cmd);
122 extern void free_msg(struct msg_msg *msg);
123 extern struct msg_msg *load_msg(const void __user *src, int len);
124 extern int store_msg(void __user *dest, struct msg_msg *msg, int len);
125 extern int ipcget_new(struct ipc_namespace *, struct ipc_ids *,
126 struct ipc_ops *, struct ipc_params *);
127 extern int ipcget_public(struct ipc_namespace *, struct ipc_ids *,
128 struct ipc_ops *, struct ipc_params *);
130 static inline int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
131 struct ipc_ops *ops, struct ipc_params *params)
133 if (params->key == IPC_PRIVATE)
134 return ipcget_new(ns, ids, ops, params);
136 return ipcget_public(ns, ids, ops, params);