br_notify.c
/*
* Device event handling
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/rtnetlink.h>
#include <net/net_namespace.h>
#include "br_private.h"
static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr);
struct notifier_block br_device_notifier = {
.notifier_call = br_device_event
};
/*
* Handle changes in state of network devices enslaved to a bridge.
*
* Note: don't care about up/down if bridge itself is down, because
* port state is checked when bridge is brought up.
*/
static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
{
struct net_device *dev = ptr;
struct net_bridge_port *p;
struct net_bridge *br;
bool changed_addr;
int err;
/* register of bridge completed, add sysfs entries */
if ((dev->priv_flags & IFF_EBRIDGE) && event == NETDEV_REGISTER) {
br_sysfs_addbr(dev);
return NOTIFY_DONE;
}
/* not a port of a bridge */
p = br_port_get_rtnl(dev);
if (!p)
return NOTIFY_DONE;
br = p->br;
switch (event) {
case NETDEV_CHANGEMTU:
dev_set_mtu(br->dev, br_min_mtu(br));
break;
case NETDEV_CHANGEADDR:
spin_lock_bh(&br->lock);
br_fdb_changeaddr(p, dev->dev_addr);
changed_addr = br_stp_recalculate_bridge_id(br);
spin_unlock_bh(&br->lock);
if (changed_addr)
call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
break;
case NETDEV_CHANGE:
br_port_carrier_check(p);
break;
case NETDEV_FEAT_CHANGE:
netdev_update_features(br->dev);
break;
case NETDEV_DOWN:
spin_lock_bh(&br->lock);
if (br->dev->flags & IFF_UP)
br_stp_disable_port(p);
spin_unlock_bh(&br->lock);
break;
case NETDEV_UP:
if (netif_carrier_ok(dev) && (br->dev->flags & IFF_UP)) {
spin_lock_bh(&br->lock);
br_stp_enable_port(p);
spin_unlock_bh(&br->lock);
}
break;
case NETDEV_UNREGISTER:
br_del_if(br, dev);
break;
case NETDEV_CHANGENAME:
err = br_sysfs_renameif(p);
if (err)
return notifier_from_errno(err);
break;
case NETDEV_PRE_TYPE_CHANGE:
/* Forbid underlaying device to change its type. */
return NOTIFY_BAD;
}
/* Events that may cause spanning tree to refresh */
if (event == NETDEV_CHANGEADDR || event == NETDEV_UP ||
event == NETDEV_CHANGE || event == NETDEV_DOWN)
br_ifinfo_notify(RTM_NEWLINK, p);
return NOTIFY_DONE;
}