usb: catc free urb cleanup
[usb.git] / kernel / nsproxy.c
blob674aceb7335ad56f7a2a8ba2996d0faa4ed850db
1 /*
2 * Copyright (C) 2006 IBM Corporation
4 * Author: Serge Hallyn <serue@us.ibm.com>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation, version 2 of the
9 * License.
11 * Jun 2006 - namespaces support
12 * OpenVZ, SWsoft Inc.
13 * Pavel Emelianov <xemul@openvz.org>
16 #include <linux/module.h>
17 #include <linux/version.h>
18 #include <linux/nsproxy.h>
19 #include <linux/init_task.h>
20 #include <linux/namespace.h>
21 #include <linux/utsname.h>
23 struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy);
25 static inline void get_nsproxy(struct nsproxy *ns)
27 atomic_inc(&ns->count);
30 void get_task_namespaces(struct task_struct *tsk)
32 struct nsproxy *ns = tsk->nsproxy;
33 if (ns) {
34 get_nsproxy(ns);
39 * creates a copy of "orig" with refcount 1.
40 * This does not grab references to the contained namespaces,
41 * so that needs to be done by dup_namespaces.
43 static inline struct nsproxy *clone_namespaces(struct nsproxy *orig)
45 struct nsproxy *ns;
47 ns = kmemdup(orig, sizeof(struct nsproxy), GFP_KERNEL);
48 if (ns)
49 atomic_set(&ns->count, 1);
50 return ns;
54 * copies the nsproxy, setting refcount to 1, and grabbing a
55 * reference to all contained namespaces. Called from
56 * sys_unshare()
58 struct nsproxy *dup_namespaces(struct nsproxy *orig)
60 struct nsproxy *ns = clone_namespaces(orig);
62 if (ns) {
63 if (ns->namespace)
64 get_namespace(ns->namespace);
65 if (ns->uts_ns)
66 get_uts_ns(ns->uts_ns);
67 if (ns->ipc_ns)
68 get_ipc_ns(ns->ipc_ns);
71 return ns;
75 * called from clone. This now handles copy for nsproxy and all
76 * namespaces therein.
78 int copy_namespaces(int flags, struct task_struct *tsk)
80 struct nsproxy *old_ns = tsk->nsproxy;
81 struct nsproxy *new_ns;
82 int err = 0;
84 if (!old_ns)
85 return 0;
87 get_nsproxy(old_ns);
89 if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC)))
90 return 0;
92 new_ns = clone_namespaces(old_ns);
93 if (!new_ns) {
94 err = -ENOMEM;
95 goto out;
98 tsk->nsproxy = new_ns;
100 err = copy_namespace(flags, tsk);
101 if (err)
102 goto out_ns;
104 err = copy_utsname(flags, tsk);
105 if (err)
106 goto out_uts;
108 err = copy_ipcs(flags, tsk);
109 if (err)
110 goto out_ipc;
112 out:
113 put_nsproxy(old_ns);
114 return err;
116 out_ipc:
117 if (new_ns->uts_ns)
118 put_uts_ns(new_ns->uts_ns);
119 out_uts:
120 if (new_ns->namespace)
121 put_namespace(new_ns->namespace);
122 out_ns:
123 tsk->nsproxy = old_ns;
124 kfree(new_ns);
125 goto out;
128 void free_nsproxy(struct nsproxy *ns)
130 if (ns->namespace)
131 put_namespace(ns->namespace);
132 if (ns->uts_ns)
133 put_uts_ns(ns->uts_ns);
134 if (ns->ipc_ns)
135 put_ipc_ns(ns->ipc_ns);
136 kfree(ns);