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