xref: /linux/net/core/netevent.c (revision aa23aa55166c2865ac430168c4b9d405cf8c6980)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Network event notifiers
4  *
5  *	Authors:
6  *      Tom Tucker             <tom@opengridcomputing.com>
7  *      Steve Wise             <swise@opengridcomputing.com>
8  *
9  *	Fixes:
10  */
11 
12 #include <linux/rtnetlink.h>
13 #include <linux/notifier.h>
14 #include <linux/export.h>
15 #include <net/netevent.h>
16 
17 static ATOMIC_NOTIFIER_HEAD(netevent_notif_chain);
18 
19 /**
20  *	register_netevent_notifier - register a netevent notifier block
21  *	@nb: notifier
22  *
23  *	Register a notifier to be called when a netevent occurs.
24  *	The notifier passed is linked into the kernel structures and must
25  *	not be reused until it has been unregistered. A negative errno code
26  *	is returned on a failure.
27  */
28 int register_netevent_notifier(struct notifier_block *nb)
29 {
30 	return atomic_notifier_chain_register(&netevent_notif_chain, nb);
31 }
32 EXPORT_SYMBOL_GPL(register_netevent_notifier);
33 
34 /**
35  *	netevent_unregister_notifier - unregister a netevent notifier block
36  *	@nb: notifier
37  *
38  *	Unregister a notifier previously registered by
39  *	register_neigh_notifier(). The notifier is unlinked into the
40  *	kernel structures and may then be reused. A negative errno code
41  *	is returned on a failure.
42  */
43 
44 int unregister_netevent_notifier(struct notifier_block *nb)
45 {
46 	return atomic_notifier_chain_unregister(&netevent_notif_chain, nb);
47 }
48 EXPORT_SYMBOL_GPL(unregister_netevent_notifier);
49 
50 /**
51  *	call_netevent_notifiers - call all netevent notifier blocks
52  *      @val: value passed unmodified to notifier function
53  *      @v:   pointer passed unmodified to notifier function
54  *
55  *	Call all neighbour notifier blocks.  Parameters and return value
56  *	are as for notifier_call_chain().
57  */
58 
59 int call_netevent_notifiers(unsigned long val, void *v)
60 {
61 	return atomic_notifier_call_chain(&netevent_notif_chain, val, v);
62 }
63 EXPORT_SYMBOL_GPL(call_netevent_notifiers);
64