xref: /openbmc/linux/net/core/netevent.c (revision e868d61272caa648214046a096e5a6bfc068dc8c)
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 
19 static ATOMIC_NOTIFIER_HEAD(netevent_notif_chain);
20 
21 /**
22  *	register_netevent_notifier - register a netevent notifier block
23  *	@nb: notifier
24  *
25  *	Register a notifier to be called when a netevent occurs.
26  *	The notifier passed is linked into the kernel structures and must
27  *	not be reused until it has been unregistered. A negative errno code
28  *	is returned on a failure.
29  */
30 int register_netevent_notifier(struct notifier_block *nb)
31 {
32 	int err;
33 
34 	err = atomic_notifier_chain_register(&netevent_notif_chain, nb);
35 	return err;
36 }
37 
38 /**
39  *	netevent_unregister_notifier - unregister a netevent notifier block
40  *	@nb: notifier
41  *
42  *	Unregister a notifier previously registered by
43  *	register_neigh_notifier(). The notifier is unlinked into the
44  *	kernel structures and may then be reused. A negative errno code
45  *	is returned on a failure.
46  */
47 
48 int unregister_netevent_notifier(struct notifier_block *nb)
49 {
50 	return atomic_notifier_chain_unregister(&netevent_notif_chain, nb);
51 }
52 
53 /**
54  *	call_netevent_notifiers - call all netevent notifier blocks
55  *      @val: value passed unmodified to notifier function
56  *      @v:   pointer passed unmodified to notifier function
57  *
58  *	Call all neighbour notifier blocks.  Parameters and return value
59  *	are as for notifier_call_chain().
60  */
61 
62 int call_netevent_notifiers(unsigned long val, void *v)
63 {
64 	return atomic_notifier_call_chain(&netevent_notif_chain, val, v);
65 }
66 
67 EXPORT_SYMBOL_GPL(register_netevent_notifier);
68 EXPORT_SYMBOL_GPL(unregister_netevent_notifier);
69 EXPORT_SYMBOL_GPL(call_netevent_notifiers);
70