3 * Linux ethernet bridge
6 * Lennert Buytenhek <buytenh@gnu.org>
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.
14 #include <linux/kernel.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/netpoll.h>
18 #include <linux/ethtool.h>
19 #include <linux/if_arp.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/rtnetlink.h>
23 #include <linux/if_ether.h>
24 #include <linux/slab.h>
26 #include <linux/if_vlan.h>
28 #include "br_private.h"
31 * Determine initial path cost based on speed.
32 * using recommendations from 802.1d standard
34 * Since driver might sleep need to not be holding any locks.
36 static int port_cost(struct net_device *dev)
38 struct ethtool_cmd ecmd;
40 if (!__ethtool_get_settings(dev, &ecmd)) {
41 switch (ethtool_cmd_speed(&ecmd)) {
53 /* Old silly heuristics based on name */
54 if (!strncmp(dev->name, "lec", 3))
57 if (!strncmp(dev->name, "plip", 4))
60 return 100; /* assume old 10Mbps */
64 /* Check for port carrier transistions. */
65 void br_port_carrier_check(struct net_bridge_port *p)
67 struct net_device *dev = p->dev;
68 struct net_bridge *br = p->br;
70 if (!(p->flags & BR_ADMIN_COST) &&
71 netif_running(dev) && netif_oper_up(dev))
72 p->path_cost = port_cost(dev);
74 if (!netif_running(br->dev))
77 spin_lock_bh(&br->lock);
78 if (netif_running(dev) && netif_oper_up(dev)) {
79 if (p->state == BR_STATE_DISABLED)
80 br_stp_enable_port(p);
82 if (p->state != BR_STATE_DISABLED)
83 br_stp_disable_port(p);
85 spin_unlock_bh(&br->lock);
88 static void release_nbp(struct kobject *kobj)
90 struct net_bridge_port *p
91 = container_of(kobj, struct net_bridge_port, kobj);
95 static struct kobj_type brport_ktype = {
97 .sysfs_ops = &brport_sysfs_ops,
99 .release = release_nbp,
102 static void destroy_nbp(struct net_bridge_port *p)
104 struct net_device *dev = p->dev;
110 kobject_put(&p->kobj);
113 static void destroy_nbp_rcu(struct rcu_head *head)
115 struct net_bridge_port *p =
116 container_of(head, struct net_bridge_port, rcu);
120 /* Delete port(interface) from bridge is done in two steps.
121 * via RCU. First step, marks device as down. That deletes
122 * all the timers and stops new packets from flowing through.
124 * Final cleanup doesn't occur until after all CPU's finished
125 * processing packets.
127 * Protected from multiple admin operations by RTNL mutex
129 static void del_nbp(struct net_bridge_port *p)
131 struct net_bridge *br = p->br;
132 struct net_device *dev = p->dev;
134 sysfs_remove_link(br->ifobj, p->dev->name);
136 dev_set_promiscuity(dev, -1);
138 spin_lock_bh(&br->lock);
139 br_stp_disable_port(p);
140 spin_unlock_bh(&br->lock);
142 br_ifinfo_notify(RTM_DELLINK, p);
145 br_fdb_delete_by_port(br, p, 1);
147 list_del_rcu(&p->list);
149 dev->priv_flags &= ~IFF_BRIDGE_PORT;
151 netdev_rx_handler_unregister(dev);
154 netdev_upper_dev_unlink(dev, br->dev);
156 br_multicast_del_port(p);
158 kobject_uevent(&p->kobj, KOBJ_REMOVE);
159 kobject_del(&p->kobj);
161 br_netpoll_disable(p);
163 call_rcu(&p->rcu, destroy_nbp_rcu);
166 /* Delete bridge device */
167 void br_dev_delete(struct net_device *dev, struct list_head *head)
169 struct net_bridge *br = netdev_priv(dev);
170 struct net_bridge_port *p, *n;
172 list_for_each_entry_safe(p, n, &br->port_list, list) {
176 del_timer_sync(&br->gc_timer);
178 br_sysfs_delbr(br->dev);
179 unregister_netdevice_queue(br->dev, head);
182 /* find an available port number */
183 static int find_portno(struct net_bridge *br)
186 struct net_bridge_port *p;
187 unsigned long *inuse;
189 inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
194 set_bit(0, inuse); /* zero is reserved */
195 list_for_each_entry(p, &br->port_list, list) {
196 set_bit(p->port_no, inuse);
198 index = find_first_zero_bit(inuse, BR_MAX_PORTS);
201 return (index >= BR_MAX_PORTS) ? -EXFULL : index;
204 /* called with RTNL but without bridge lock */
205 static struct net_bridge_port *new_nbp(struct net_bridge *br,
206 struct net_device *dev)
209 struct net_bridge_port *p;
211 index = find_portno(br);
213 return ERR_PTR(index);
215 p = kzalloc(sizeof(*p), GFP_KERNEL);
217 return ERR_PTR(-ENOMEM);
222 p->path_cost = port_cost(dev);
223 p->priority = 0x8000 >> BR_PORT_BITS;
227 p->state = BR_STATE_DISABLED;
228 br_stp_port_timer_init(p);
229 br_multicast_add_port(p);
234 int br_add_bridge(struct net *net, const char *name)
236 struct net_device *dev;
239 dev = alloc_netdev(sizeof(struct net_bridge), name,
245 dev_net_set(dev, net);
246 dev->rtnl_link_ops = &br_link_ops;
248 res = register_netdev(dev);
254 int br_del_bridge(struct net *net, const char *name)
256 struct net_device *dev;
260 dev = __dev_get_by_name(net, name);
262 ret = -ENXIO; /* Could not find device */
264 else if (!(dev->priv_flags & IFF_EBRIDGE)) {
265 /* Attempt to delete non bridge device! */
269 else if (dev->flags & IFF_UP) {
270 /* Not shutdown yet. */
275 br_dev_delete(dev, NULL);
281 /* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
282 int br_min_mtu(const struct net_bridge *br)
284 const struct net_bridge_port *p;
289 if (list_empty(&br->port_list))
292 list_for_each_entry(p, &br->port_list, list) {
293 if (!mtu || p->dev->mtu < mtu)
301 * Recomputes features using slave's features
303 netdev_features_t br_features_recompute(struct net_bridge *br,
304 netdev_features_t features)
306 struct net_bridge_port *p;
307 netdev_features_t mask;
309 if (list_empty(&br->port_list))
313 features &= ~NETIF_F_ONE_FOR_ALL;
315 list_for_each_entry(p, &br->port_list, list) {
316 features = netdev_increment_features(features,
317 p->dev->features, mask);
323 /* called with RTNL */
324 int br_add_if(struct net_bridge *br, struct net_device *dev)
326 struct net_bridge_port *p;
330 /* Don't allow bridging non-ethernet like devices */
331 if ((dev->flags & IFF_LOOPBACK) ||
332 dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN ||
333 !is_valid_ether_addr(dev->dev_addr))
336 /* No bridging of bridges */
337 if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
340 /* Device is already being bridged */
341 if (br_port_exists(dev))
344 /* No bridging devices that dislike that (e.g. wireless) */
345 if (dev->priv_flags & IFF_DONT_BRIDGE)
348 p = new_nbp(br, dev);
352 call_netdevice_notifiers(NETDEV_JOIN, dev);
354 err = dev_set_promiscuity(dev, 1);
358 err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
359 SYSFS_BRIDGE_PORT_ATTR);
363 err = br_sysfs_addif(p);
367 if (br_netpoll_info(br) && ((err = br_netpoll_enable(p, GFP_KERNEL))))
370 err = netdev_master_upper_dev_link(dev, br->dev);
374 err = netdev_rx_handler_register(dev, br_handle_frame, p);
378 dev->priv_flags |= IFF_BRIDGE_PORT;
380 dev_disable_lro(dev);
382 list_add_rcu(&p->list, &br->port_list);
384 netdev_update_features(br->dev);
386 spin_lock_bh(&br->lock);
387 changed_addr = br_stp_recalculate_bridge_id(br);
389 if (netif_running(dev) && netif_oper_up(dev) &&
390 (br->dev->flags & IFF_UP))
391 br_stp_enable_port(p);
392 spin_unlock_bh(&br->lock);
394 br_ifinfo_notify(RTM_NEWLINK, p);
397 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
399 dev_set_mtu(br->dev, br_min_mtu(br));
401 if (br_fdb_insert(br, p, dev->dev_addr, 0))
402 netdev_err(dev, "failed insert local address bridge forwarding table\n");
404 kobject_uevent(&p->kobj, KOBJ_ADD);
409 netdev_upper_dev_unlink(dev, br->dev);
411 br_netpoll_disable(p);
413 sysfs_remove_link(br->ifobj, p->dev->name);
415 kobject_put(&p->kobj);
416 p = NULL; /* kobject_put frees */
418 dev_set_promiscuity(dev, -1);
425 /* called with RTNL */
426 int br_del_if(struct net_bridge *br, struct net_device *dev)
428 struct net_bridge_port *p;
431 p = br_port_get_rtnl(dev);
432 if (!p || p->br != br)
435 /* Since more than one interface can be attached to a bridge,
436 * there still maybe an alternate path for netconsole to use;
437 * therefore there is no reason for a NETDEV_RELEASE event.
441 spin_lock_bh(&br->lock);
442 changed_addr = br_stp_recalculate_bridge_id(br);
443 spin_unlock_bh(&br->lock);
446 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
448 netdev_update_features(br->dev);
453 void __net_exit br_net_exit(struct net *net)
455 struct net_device *dev;
459 for_each_netdev(net, dev)
460 if (dev->priv_flags & IFF_EBRIDGE)
461 br_dev_delete(dev, &list);
463 unregister_netdevice_many(&list);