LXR linux/net/core/netevent.c

   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
  21static 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 */
  32int register_netevent_notifier(struct notifier_block *nb)
  33{
  34        return atomic_notifier_chain_register(&netevent_notif_chain, nb);
  35}
  36EXPORT_SYMBOL_GPL(register_netevent_notifier);
  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
  48int unregister_netevent_notifier(struct notifier_block *nb)
  49{
  50        return atomic_notifier_chain_unregister(&netevent_notif_chain, nb);
  51}
  52EXPORT_SYMBOL_GPL(unregister_netevent_notifier);
  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
  63int call_netevent_notifiers(unsigned long val, void *v)
  64{
  65        return atomic_notifier_call_chain(&netevent_notif_chain, val, v);
  66}
  67EXPORT_SYMBOL_GPL(call_netevent_notifiers);
  68