LXR linux/net/bridge/br

   1/*
   2 *      Device event handling
   3 *      Linux ethernet bridge
   4 *
   5 *      Authors:
   6 *      Lennert Buytenhek               <buytenh@gnu.org>
   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
  14#include <linux/kernel.h>
  15#include <linux/rtnetlink.h>
  16#include <net/net_namespace.h>
  17
  18#include "br_private.h"
  19
  20static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr);
  21
  22struct notifier_block br_device_notifier = {
  23        .notifier_call = br_device_event
  24};
  25
  26/*
  27 * Handle changes in state of network devices enslaved to a bridge.
  28 *
  29 * Note: don't care about up/down if bridge itself is down, because
  30 *     port state is checked when bridge is brought up.
  31 */
  32static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
  33{
  34        struct net_device *dev = netdev_notifier_info_to_dev(ptr);
  35        struct net_bridge_port *p;
  36        struct net_bridge *br;
  37        bool changed_addr;
  38        int err;
  39
  40        /* register of bridge completed, add sysfs entries */
  41        if ((dev->priv_flags & IFF_EBRIDGE) && event == NETDEV_REGISTER) {
  42                br_sysfs_addbr(dev);
  43                return NOTIFY_DONE;
  44        }
  45
  46        /* not a port of a bridge */
  47        p = br_port_get_rtnl(dev);
  48        if (!p)
  49                return NOTIFY_DONE;
  50
  51        br = p->br;
  52
  53        switch (event) {
  54        case NETDEV_CHANGEMTU:
  55                dev_set_mtu(br->dev, br_min_mtu(br));
  56                break;
  57
  58        case NETDEV_CHANGEADDR:
  59                spin_lock_bh(&br->lock);
  60                br_fdb_changeaddr(p, dev->dev_addr);
  61                changed_addr = br_stp_recalculate_bridge_id(br);
  62                spin_unlock_bh(&br->lock);
  63
  64                if (changed_addr)
  65                        call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
  66
  67                break;
  68
  69        case NETDEV_CHANGE:
  70                br_port_carrier_check(p);
  71                break;
  72
  73        case NETDEV_FEAT_CHANGE:
  74                netdev_update_features(br->dev);
  75                break;
  76
  77        case NETDEV_DOWN:
  78                spin_lock_bh(&br->lock);
  79                if (br->dev->flags & IFF_UP)
  80                        br_stp_disable_port(p);
  81                spin_unlock_bh(&br->lock);
  82                break;
  83
  84        case NETDEV_UP:
  85                if (netif_running(br->dev) && netif_oper_up(dev)) {
  86                        spin_lock_bh(&br->lock);
  87                        br_stp_enable_port(p);
  88                        spin_unlock_bh(&br->lock);
  89                }
  90                break;
  91
  92        case NETDEV_UNREGISTER:
  93                br_del_if(br, dev);
  94                break;
  95
  96        case NETDEV_CHANGENAME:
  97                err = br_sysfs_renameif(p);
  98                if (err)
  99                        return notifier_from_errno(err);
 100                break;
 101
 102        case NETDEV_PRE_TYPE_CHANGE:
 103                /* Forbid underlaying device to change its type. */
 104                return NOTIFY_BAD;
 105        }
 106
 107        /* Events that may cause spanning tree to refresh */
 108        if (event == NETDEV_CHANGEADDR || event == NETDEV_UP ||
 109            event == NETDEV_CHANGE || event == NETDEV_DOWN)
 110                br_ifinfo_notify(RTM_NEWLINK, p);
 111
 112        return NOTIFY_DONE;
 113}
 114