V4L/DVB (7140): constify function pointer tables
[linux-2.6/openmoko-kernel/knife-kernel.git] / ipc / namespace.c
blob1b967655eb350eba0c4308998e376a8d3a719c72
1 /*
2 * linux/ipc/namespace.c
3 * Copyright (C) 2006 Pavel Emelyanov <xemul@openvz.org> OpenVZ, SWsoft Inc.
4 */
6 #include <linux/ipc.h>
7 #include <linux/msg.h>
8 #include <linux/ipc_namespace.h>
9 #include <linux/rcupdate.h>
10 #include <linux/nsproxy.h>
11 #include <linux/slab.h>
13 #include "util.h"
15 static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns)
17 struct ipc_namespace *ns;
19 ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL);
20 if (ns == NULL)
21 return ERR_PTR(-ENOMEM);
23 sem_init_ns(ns);
24 msg_init_ns(ns);
25 shm_init_ns(ns);
27 kref_init(&ns->kref);
28 return ns;
31 struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *ns)
33 struct ipc_namespace *new_ns;
35 BUG_ON(!ns);
36 get_ipc_ns(ns);
38 if (!(flags & CLONE_NEWIPC))
39 return ns;
41 new_ns = clone_ipc_ns(ns);
43 put_ipc_ns(ns);
44 return new_ns;
48 * free_ipcs - free all ipcs of one type
49 * @ns: the namespace to remove the ipcs from
50 * @ids: the table of ipcs to free
51 * @free: the function called to free each individual ipc
53 * Called for each kind of ipc when an ipc_namespace exits.
55 void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
56 void (*free)(struct ipc_namespace *, struct kern_ipc_perm *))
58 struct kern_ipc_perm *perm;
59 int next_id;
60 int total, in_use;
62 down_write(&ids->rw_mutex);
64 in_use = ids->in_use;
66 for (total = 0, next_id = 0; total < in_use; next_id++) {
67 perm = idr_find(&ids->ipcs_idr, next_id);
68 if (perm == NULL)
69 continue;
70 ipc_lock_by_ptr(perm);
71 free(ns, perm);
72 total++;
74 up_write(&ids->rw_mutex);
77 void free_ipc_ns(struct kref *kref)
79 struct ipc_namespace *ns;
81 ns = container_of(kref, struct ipc_namespace, kref);
82 sem_exit_ns(ns);
83 msg_exit_ns(ns);
84 shm_exit_ns(ns);
85 kfree(ns);