xref: /openbmc/linux/net/core/netevent.c (revision 0da85d1e)
1 /*
2  *	Network event notifiers
3  *
4  *	Authors:
5  *      Tom Tucker             <tom@opengridcomputing.com>
6  *      Steve Wise             <swise@opengridcomputing.com>
7  *
8  *	This program is free software; you can redistribute it and/or
9  *      modify it under the terms of the GNU General Public License
10  *      as published by the Free Software Foundation; either version
11  *      2 of the License, or (at your option) any later version.
12  *
13  *	Fixes:
14  */
15 
16 #include <linux/rtnetlink.h>
17 #include <linux/notifier.h>
18 #include <linux/export.h>
19 #include <net/netevent.h>
20 
21 static ATOMIC_NOTIFIER_HEAD(netevent_notif_chain);
22 
23 /**
24  *	register_netevent_notifier - register a netevent notifier block
25  *	@nb: notifier
26  *
27  *	Register a notifier to be called when a netevent occurs.
28  *	The notifier passed is linked into the kernel structures and must
29  *	not be reused until it has been unregistered. A negative errno code
30  *	is returned on a failure.
31  */
32 int register_netevent_notifier(struct notifier_block *nb)
33 {
34 	int err;
35 
36 	err = atomic_notifier_chain_register(&netevent_notif_chain, nb);
37 	return err;
38 }
39 EXPORT_SYMBOL_GPL(register_netevent_notifier);
40 
41 /**
42  *	netevent_unregister_notifier - unregister a netevent notifier block
43  *	@nb: notifier
44  *
45  *	Unregister a notifier previously registered by
46  *	register_neigh_notifier(). The notifier is unlinked into the
47  *	kernel structures and may then be reused. A negative errno code
48  *	is returned on a failure.
49  */
50 
51 int unregister_netevent_notifier(struct notifier_block *nb)
52 {
53 	return atomic_notifier_chain_unregister(&netevent_notif_chain, nb);
54 }
55 EXPORT_SYMBOL_GPL(unregister_netevent_notifier);
56 
57 /**
58  *	call_netevent_notifiers - call all netevent notifier blocks
59  *      @val: value passed unmodified to notifier function
60  *      @v:   pointer passed unmodified to notifier function
61  *
62  *	Call all neighbour notifier blocks.  Parameters and return value
63  *	are as for notifier_call_chain().
64  */
65 
66 int call_netevent_notifiers(unsigned long val, void *v)
67 {
68 	return atomic_notifier_call_chain(&netevent_notif_chain, val, v);
69 }
70 EXPORT_SYMBOL_GPL(call_netevent_notifiers);
71