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 = br_port_get(dev);
  36         struct net_bridge *br;
  37         int err;
  38
  39         /* not a port of a bridge */
  40         if (!br_port_exists(dev))
  41                 return NOTIFY_DONE;
  42
  43         p = br_port_get(dev);
  44         br = p->br;
  45
  46         switch (event) {
  47         case NETDEV_CHANGEMTU:
  48                 dev_set_mtu(br->dev, br_min_mtu(br));
  49                 break;
  50
  51         case NETDEV_CHANGEADDR:
  52                 spin_lock_bh(&br->lock);
  53                 br_fdb_changeaddr(p, dev->dev_addr);
  54                 br_stp_recalculate_bridge_id(br);
  55                 spin_unlock_bh(&br->lock);
  56                 break;
  57
  58         case NETDEV_CHANGE:
  59                 br_port_carrier_check(p);
  60                 break;
  61
  62         case NETDEV_FEAT_CHANGE:
  63                 spin_lock_bh(&br->lock);
  64                 if (netif_running(br->dev))
  65                         br_features_recompute(br);
  66                 spin_unlock_bh(&br->lock);
  67                 break;
  68
  69         case NETDEV_DOWN:
  70                 spin_lock_bh(&br->lock);
  71                 if (br->dev->flags & IFF_UP)
  72                         br_stp_disable_port(p);
  73                 spin_unlock_bh(&br->lock);
  74                 break;
  75
  76         case NETDEV_UP:
  77                 if (netif_carrier_ok(dev) && (br->dev->flags & IFF_UP)) {
  78                         spin_lock_bh(&br->lock);
  79                         br_stp_enable_port(p);
  80                         spin_unlock_bh(&br->lock);
  81                 }
  82                 break;
  83
  84         case NETDEV_UNREGISTER:
  85                 br_del_if(br, dev);
  86                 break;
  87
  88         case NETDEV_CHANGENAME:
  89                 err = br_sysfs_renameif(p);
  90                 if (err)
  91                         return notifier_from_errno(err);
  92                 break;
  93
  94         case NETDEV_PRE_TYPE_CHANGE:
  95                 /* Forbid underlaying device to change its type. */
  96                 return NOTIFY_BAD;
  97         }
  98
  99         /* Events that may cause spanning tree to refresh */
 100         if (event == NETDEV_CHANGEADDR || event == NETDEV_UP ||
 101             event == NETDEV_CHANGE || event == NETDEV_DOWN)
 102                 br_ifinfo_notify(RTM_NEWLINK, p);
 103
 104         return NOTIFY_DONE;
 105 }