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  *      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
  20 static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr);
  21
  22 struct 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  */
  32 static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
  33 {
  34         struct net_device *dev = ptr;
  35         struct net_bridge_port *p = dev->br_port;
  36         struct net_bridge *br;
  37
  38         /* not a port of a bridge */
  39         if (p == NULL)
  40                 return NOTIFY_DONE;
  41
  42         br = p->br;
  43
  44         switch (event) {
  45         case NETDEV_CHANGEMTU:
  46                 dev_set_mtu(br->dev, br_min_mtu(br));
  47                 break;
  48
  49         case NETDEV_CHANGEADDR:
  50                 spin_lock_bh(&br->lock);
  51                 br_fdb_changeaddr(p, dev->dev_addr);
  52                 br_stp_recalculate_bridge_id(br);
  53                 spin_unlock_bh(&br->lock);
  54                 break;
  55
  56         case NETDEV_CHANGE:
  57                 br_port_carrier_check(p);
  58                 break;
  59
  60         case NETDEV_FEAT_CHANGE:
  61                 spin_lock_bh(&br->lock);
  62                 if (netif_running(br->dev))
  63                         br_features_recompute(br);
  64                 spin_unlock_bh(&br->lock);
  65                 break;
  66
  67         case NETDEV_DOWN:
  68                 spin_lock_bh(&br->lock);
  69                 if (br->dev->flags & IFF_UP)
  70                         br_stp_disable_port(p);
  71                 spin_unlock_bh(&br->lock);
  72                 break;
  73
  74         case NETDEV_UP:
  75                 if (netif_carrier_ok(dev) && (br->dev->flags & IFF_UP)) {
  76                         spin_lock_bh(&br->lock);
  77                         br_stp_enable_port(p);
  78                         spin_unlock_bh(&br->lock);
  79                 }
  80                 break;
  81
  82         case NETDEV_UNREGISTER:
  83                 br_del_if(br, dev);
  84                 break;
  85         }
  86
  87         /* Events that may cause spanning tree to refresh */
  88         if (event == NETDEV_CHANGEADDR || event == NETDEV_UP ||
  89             event == NETDEV_CHANGE || event == NETDEV_DOWN)
  90                 br_ifinfo_notify(RTM_NEWLINK, p);
  91
  92         return NOTIFY_DONE;
  93 }