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 */
br_device_event(struct notifier_block * unused,unsigned long event,void * ptr)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;
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