1// SPDX-License-Identifier: GPL-2.0
2/* Kernel object name space definitions
3 *
4 * Copyright (c) 2002-2003 Patrick Mochel
5 * Copyright (c) 2002-2003 Open Source Development Labs
6 * Copyright (c) 2006-2008 Greg Kroah-Hartman <greg@kroah.com>
7 * Copyright (c) 2006-2008 Novell Inc.
8 *
9 * Split from kobject.h by David Howells (dhowells@redhat.com)
10 *
11 * Please read Documentation/core-api/kobject.rst before using the kobject
12 * interface, ESPECIALLY the parts about reference counts and object
13 * destructors.
14 */
15
16#ifndef _LINUX_KOBJECT_NS_H
17#define _LINUX_KOBJECT_NS_H
18
19struct sock;
20struct kobject;
21
22/*
23 * Namespace types which are used to tag kobjects and sysfs entries.
24 * Network namespace will likely be the first.
25 */
26enum kobj_ns_type {
27	KOBJ_NS_TYPE_NONE = 0,
28	KOBJ_NS_TYPE_NET,
29	KOBJ_NS_TYPES
30};
31
32/*
33 * Callbacks so sysfs can determine namespaces
34 *   @grab_current_ns: return a new reference to calling task's namespace
35 *   @netlink_ns: return namespace to which a sock belongs (right?)
36 *   @initial_ns: return the initial namespace (i.e. init_net_ns)
37 *   @drop_ns: drops a reference to namespace
38 */
39struct kobj_ns_type_operations {
40	enum kobj_ns_type type;
41	bool (*current_may_mount)(void);
42	void *(*grab_current_ns)(void);
43	const void *(*netlink_ns)(struct sock *sk);
44	const void *(*initial_ns)(void);
45	void (*drop_ns)(void *);
46};
47
48int kobj_ns_type_register(const struct kobj_ns_type_operations *ops);
49int kobj_ns_type_registered(enum kobj_ns_type type);
50const struct kobj_ns_type_operations *kobj_child_ns_ops(const struct kobject *parent);
51const struct kobj_ns_type_operations *kobj_ns_ops(const struct kobject *kobj);
52
53bool kobj_ns_current_may_mount(enum kobj_ns_type type);
54void *kobj_ns_grab_current(enum kobj_ns_type type);
55const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk);
56const void *kobj_ns_initial(enum kobj_ns_type type);
57void kobj_ns_drop(enum kobj_ns_type type, void *ns);
58
59#endif /* _LINUX_KOBJECT_NS_H */
60