ext4: Fix race in ext4_inode_info.i_cached_extent
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / include / linux / ipc_namespace.h
blobea330f9e710015c2c8a4b80ebfaec9cd133ffcdd
1 #ifndef __IPC_NAMESPACE_H__
2 #define __IPC_NAMESPACE_H__
4 #include <linux/err.h>
5 #include <linux/idr.h>
6 #include <linux/rwsem.h>
7 #include <linux/notifier.h>
9 /*
10 * ipc namespace events
12 #define IPCNS_MEMCHANGED 0x00000001 /* Notify lowmem size changed */
13 #define IPCNS_CREATED 0x00000002 /* Notify new ipc namespace created */
14 #define IPCNS_REMOVED 0x00000003 /* Notify ipc namespace removed */
16 #define IPCNS_CALLBACK_PRI 0
19 struct ipc_ids {
20 int in_use;
21 unsigned short seq;
22 unsigned short seq_max;
23 struct rw_semaphore rw_mutex;
24 struct idr ipcs_idr;
27 struct ipc_namespace {
28 struct kref kref;
29 struct ipc_ids ids[3];
31 int sem_ctls[4];
32 int used_sems;
34 int msg_ctlmax;
35 int msg_ctlmnb;
36 int msg_ctlmni;
37 atomic_t msg_bytes;
38 atomic_t msg_hdrs;
39 int auto_msgmni;
41 size_t shm_ctlmax;
42 size_t shm_ctlall;
43 int shm_ctlmni;
44 int shm_tot;
46 struct notifier_block ipcns_nb;
49 extern struct ipc_namespace init_ipc_ns;
50 extern atomic_t nr_ipc_ns;
52 #ifdef CONFIG_SYSVIPC
53 #define INIT_IPC_NS(ns) .ns = &init_ipc_ns,
55 extern int register_ipcns_notifier(struct ipc_namespace *);
56 extern int cond_register_ipcns_notifier(struct ipc_namespace *);
57 extern void unregister_ipcns_notifier(struct ipc_namespace *);
58 extern int ipcns_notify(unsigned long);
60 #else /* CONFIG_SYSVIPC */
61 #define INIT_IPC_NS(ns)
62 #endif /* CONFIG_SYSVIPC */
64 #if defined(CONFIG_SYSVIPC) && defined(CONFIG_IPC_NS)
65 extern void free_ipc_ns(struct kref *kref);
66 extern struct ipc_namespace *copy_ipcs(unsigned long flags,
67 struct ipc_namespace *ns);
68 extern void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
69 void (*free)(struct ipc_namespace *,
70 struct kern_ipc_perm *));
72 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
74 if (ns)
75 kref_get(&ns->kref);
76 return ns;
79 static inline void put_ipc_ns(struct ipc_namespace *ns)
81 kref_put(&ns->kref, free_ipc_ns);
83 #else
84 static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
85 struct ipc_namespace *ns)
87 if (flags & CLONE_NEWIPC)
88 return ERR_PTR(-EINVAL);
90 return ns;
93 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
95 return ns;
98 static inline void put_ipc_ns(struct ipc_namespace *ns)
101 #endif
102 #endif