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 <net/netevent.h> 19 20 static ATOMIC_NOTIFIER_HEAD(netevent_notif_chain); 21 22 /** 23 * register_netevent_notifier - register a netevent notifier block 24 * @nb: notifier 25 * 26 * Register a notifier to be called when a netevent occurs. 27 * The notifier passed is linked into the kernel structures and must 28 * not be reused until it has been unregistered. A negative errno code 29 * is returned on a failure. 30 */ 31 int register_netevent_notifier(struct notifier_block *nb) 32 { 33 int err; 34 35 err = atomic_notifier_chain_register(&netevent_notif_chain, nb); 36 return err; 37 } 38 39 /** 40 * netevent_unregister_notifier - unregister a netevent notifier block 41 * @nb: notifier 42 * 43 * Unregister a notifier previously registered by 44 * register_neigh_notifier(). The notifier is unlinked into the 45 * kernel structures and may then be reused. A negative errno code 46 * is returned on a failure. 47 */ 48 49 int unregister_netevent_notifier(struct notifier_block *nb) 50 { 51 return atomic_notifier_chain_unregister(&netevent_notif_chain, nb); 52 } 53 54 /** 55 * call_netevent_notifiers - call all netevent notifier blocks 56 * @val: value passed unmodified to notifier function 57 * @v: pointer passed unmodified to notifier function 58 * 59 * Call all neighbour notifier blocks. Parameters and return value 60 * are as for notifier_call_chain(). 61 */ 62 63 int call_netevent_notifiers(unsigned long val, void *v) 64 { 65 return atomic_notifier_call_chain(&netevent_notif_chain, val, v); 66 } 67 68 EXPORT_SYMBOL_GPL(register_netevent_notifier); 69 EXPORT_SYMBOL_GPL(unregister_netevent_notifier); 70 EXPORT_SYMBOL_GPL(call_netevent_notifiers); 71