net/bridge/br_notify.c

   1 /*
   2  *      Device event handling
   3  *      Linux ethernet bridge
   4  *
   5  *      Authors:
   6  *      Lennert Buytenhek               <buytenh@gnu.org>
   7  *
   8  *      $Id: br_notify.c,v 1.2 2000/02/21 15:51:34 davem Exp $
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      as published by the Free Software Foundation; either version
  13  *      2 of the License, or (at your option) any later version.
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/rtnetlink.h>
  18 #include <net/net_namespace.h>
  19
  20 #include "br_private.h"
  21
  22 static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr);
  23
  24 struct notifier_block br_device_notifier = {
  25         .notifier_call = br_device_event
  26 };
  27
  28 /*
  29  * Handle changes in state of network devices enslaved to a bridge.
  30  *
  31  * Note: don't care about up/down if bridge itself is down, because
  32  *     port state is checked when bridge is brought up.
  33  */
  34 static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
  35 {
  36         struct net_device *dev = ptr;
  37         struct net_bridge_port *p = dev->br_port;
  38         struct net_bridge *br;
  39
  40         if (dev->nd_net != &init_net)
  41                 return NOTIFY_DONE;
  42
  43         /* not a port of a bridge */
  44         if (p == NULL)
  45                 return NOTIFY_DONE;
  46
  47         br = p->br;
  48
  49         switch (event) {
  50         case NETDEV_CHANGEMTU:
  51                 dev_set_mtu(br->dev, br_min_mtu(br));
  52                 break;
  53
  54         case NETDEV_CHANGEADDR:
  55                 spin_lock_bh(&br->lock);
  56                 br_fdb_changeaddr(p, dev->dev_addr);
  57                 br_stp_recalculate_bridge_id(br);
  58                 spin_unlock_bh(&br->lock);
  59                 break;
  60
  61         case NETDEV_CHANGE:
  62                 br_port_carrier_check(p);
  63                 break;
  64
  65         case NETDEV_FEAT_CHANGE:
  66                 spin_lock_bh(&br->lock);
  67                 if (netif_running(br->dev))
  68                         br_features_recompute(br);
  69                 spin_unlock_bh(&br->lock);
  70                 break;
  71
  72         case NETDEV_DOWN:
  73                 spin_lock_bh(&br->lock);
  74                 if (br->dev->flags & IFF_UP)
  75                         br_stp_disable_port(p);
  76                 spin_unlock_bh(&br->lock);
  77                 break;
  78
  79         case NETDEV_UP:
  80                 if (netif_carrier_ok(dev) && (br->dev->flags & IFF_UP)) {
  81                         spin_lock_bh(&br->lock);
  82                         br_stp_enable_port(p);
  83                         spin_unlock_bh(&br->lock);
  84                 }
  85                 break;
  86
  87         case NETDEV_UNREGISTER:
  88                 br_del_if(br, dev);
  89                 break;
  90         }
  91
  92         /* Events that may cause spanning tree to refresh */
  93         if (event == NETDEV_CHANGEADDR || event == NETDEV_UP ||
  94             event == NETDEV_CHANGE || event == NETDEV_DOWN)
  95                 br_ifinfo_notify(RTM_NEWLINK, p);
  96
  97         return NOTIFY_DONE;
  98 }