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>
27 #include "br_private.h"
30 * Determine initial path cost based on speed.
31 * using recommendations from 802.1d standard
33 * Since driver might sleep need to not be holding any locks.
35 static int port_cost(struct net_device *dev)
37 struct ethtool_cmd ecmd;
39 if (!__ethtool_get_settings(dev, &ecmd)) {
40 switch (ethtool_cmd_speed(&ecmd)) {
52 /* Old silly heuristics based on name */
53 if (!strncmp(dev->name, "lec", 3))
56 if (!strncmp(dev->name, "plip", 4))
59 return 100; /* assume old 10Mbps */
63 /* Check for port carrier transistions. */
64 void br_port_carrier_check(struct net_bridge_port *p)
66 struct net_device *dev = p->dev;
67 struct net_bridge *br = p->br;
69 if (netif_running(dev) && netif_carrier_ok(dev))
70 p->path_cost = port_cost(dev);
72 if (!netif_running(br->dev))
75 spin_lock_bh(&br->lock);
76 if (netif_running(dev) && netif_carrier_ok(dev)) {
77 if (p->state == BR_STATE_DISABLED)
78 br_stp_enable_port(p);
80 if (p->state != BR_STATE_DISABLED)
81 br_stp_disable_port(p);
83 spin_unlock_bh(&br->lock);
86 static void release_nbp(struct kobject *kobj)
88 struct net_bridge_port *p
89 = container_of(kobj, struct net_bridge_port, kobj);
93 static struct kobj_type brport_ktype = {
95 .sysfs_ops = &brport_sysfs_ops,
97 .release = release_nbp,
100 static void destroy_nbp(struct net_bridge_port *p)
102 struct net_device *dev = p->dev;
108 kobject_put(&p->kobj);
111 static void destroy_nbp_rcu(struct rcu_head *head)
113 struct net_bridge_port *p =
114 container_of(head, struct net_bridge_port, rcu);
118 /* Delete port(interface) from bridge is done in two steps.
119 * via RCU. First step, marks device as down. That deletes
120 * all the timers and stops new packets from flowing through.
122 * Final cleanup doesn't occur until after all CPU's finished
123 * processing packets.
125 * Protected from multiple admin operations by RTNL mutex
127 static void del_nbp(struct net_bridge_port *p)
129 struct net_bridge *br = p->br;
130 struct net_device *dev = p->dev;
132 sysfs_remove_link(br->ifobj, p->dev->name);
134 dev_set_promiscuity(dev, -1);
136 spin_lock_bh(&br->lock);
137 br_stp_disable_port(p);
138 spin_unlock_bh(&br->lock);
140 br_ifinfo_notify(RTM_DELLINK, p);
142 br_fdb_delete_by_port(br, p, 1);
144 list_del_rcu(&p->list);
146 dev->priv_flags &= ~IFF_BRIDGE_PORT;
148 netdev_rx_handler_unregister(dev);
151 netdev_set_master(dev, NULL);
153 br_multicast_del_port(p);
155 kobject_uevent(&p->kobj, KOBJ_REMOVE);
156 kobject_del(&p->kobj);
158 br_netpoll_disable(p);
160 call_rcu(&p->rcu, destroy_nbp_rcu);
163 /* Delete bridge device */
164 void br_dev_delete(struct net_device *dev, struct list_head *head)
166 struct net_bridge *br = netdev_priv(dev);
167 struct net_bridge_port *p, *n;
169 list_for_each_entry_safe(p, n, &br->port_list, list) {
173 br_fdb_delete_by_port(br, NULL, 1);
175 del_timer_sync(&br->gc_timer);
177 br_sysfs_delbr(br->dev);
178 unregister_netdevice_queue(br->dev, head);
181 /* find an available port number */
182 static int find_portno(struct net_bridge *br)
185 struct net_bridge_port *p;
186 unsigned long *inuse;
188 inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
193 set_bit(0, inuse); /* zero is reserved */
194 list_for_each_entry(p, &br->port_list, list) {
195 set_bit(p->port_no, inuse);
197 index = find_first_zero_bit(inuse, BR_MAX_PORTS);
200 return (index >= BR_MAX_PORTS) ? -EXFULL : index;
203 /* called with RTNL but without bridge lock */
204 static struct net_bridge_port *new_nbp(struct net_bridge *br,
205 struct net_device *dev)
208 struct net_bridge_port *p;
210 index = find_portno(br);
212 return ERR_PTR(index);
214 p = kzalloc(sizeof(*p), GFP_KERNEL);
216 return ERR_PTR(-ENOMEM);
221 p->path_cost = port_cost(dev);
222 p->priority = 0x8000 >> BR_PORT_BITS;
226 p->state = BR_STATE_DISABLED;
227 br_stp_port_timer_init(p);
228 br_multicast_add_port(p);
233 int br_add_bridge(struct net *net, const char *name)
235 struct net_device *dev;
238 dev = alloc_netdev(sizeof(struct net_bridge), name,
244 dev_net_set(dev, net);
245 dev->rtnl_link_ops = &br_link_ops;
247 res = register_netdev(dev);
253 int br_del_bridge(struct net *net, const char *name)
255 struct net_device *dev;
259 dev = __dev_get_by_name(net, name);
261 ret = -ENXIO; /* Could not find device */
263 else if (!(dev->priv_flags & IFF_EBRIDGE)) {
264 /* Attempt to delete non bridge device! */
268 else if (dev->flags & IFF_UP) {
269 /* Not shutdown yet. */
274 br_dev_delete(dev, NULL);
280 /* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
281 int br_min_mtu(const struct net_bridge *br)
283 const struct net_bridge_port *p;
288 if (list_empty(&br->port_list))
291 list_for_each_entry(p, &br->port_list, list) {
292 if (!mtu || p->dev->mtu < mtu)
300 * Recomputes features using slave's features
302 u32 br_features_recompute(struct net_bridge *br, u32 features)
304 struct net_bridge_port *p;
307 if (list_empty(&br->port_list))
311 features &= ~NETIF_F_ONE_FOR_ALL;
313 list_for_each_entry(p, &br->port_list, list) {
314 features = netdev_increment_features(features,
315 p->dev->features, mask);
321 /* called with RTNL */
322 int br_add_if(struct net_bridge *br, struct net_device *dev)
324 struct net_bridge_port *p;
328 /* Don't allow bridging non-ethernet like devices */
329 if ((dev->flags & IFF_LOOPBACK) ||
330 dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN ||
331 !is_valid_ether_addr(dev->dev_addr))
334 /* No bridging of bridges */
335 if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
338 /* Device is already being bridged */
339 if (br_port_exists(dev))
342 /* No bridging devices that dislike that (e.g. wireless) */
343 if (dev->priv_flags & IFF_DONT_BRIDGE)
346 p = new_nbp(br, dev);
350 call_netdevice_notifiers(NETDEV_JOIN, dev);
352 err = dev_set_promiscuity(dev, 1);
356 err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
357 SYSFS_BRIDGE_PORT_ATTR);
361 err = br_sysfs_addif(p);
365 if (br_netpoll_info(br) && ((err = br_netpoll_enable(p))))
368 err = netdev_set_master(dev, br->dev);
372 err = netdev_rx_handler_register(dev, br_handle_frame, p);
376 dev->priv_flags |= IFF_BRIDGE_PORT;
378 dev_disable_lro(dev);
380 list_add_rcu(&p->list, &br->port_list);
382 netdev_update_features(br->dev);
384 spin_lock_bh(&br->lock);
385 changed_addr = br_stp_recalculate_bridge_id(br);
387 if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) &&
388 (br->dev->flags & IFF_UP))
389 br_stp_enable_port(p);
390 spin_unlock_bh(&br->lock);
392 br_ifinfo_notify(RTM_NEWLINK, p);
395 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
397 dev_set_mtu(br->dev, br_min_mtu(br));
399 if (br_fdb_insert(br, p, dev->dev_addr))
400 netdev_err(dev, "failed insert local address bridge forwarding table\n");
402 kobject_uevent(&p->kobj, KOBJ_ADD);
407 netdev_set_master(dev, NULL);
409 sysfs_remove_link(br->ifobj, p->dev->name);
411 kobject_put(&p->kobj);
412 p = NULL; /* kobject_put frees */
414 dev_set_promiscuity(dev, -1);
421 /* called with RTNL */
422 int br_del_if(struct net_bridge *br, struct net_device *dev)
424 struct net_bridge_port *p;
427 p = br_port_get_rtnl(dev);
428 if (!p || p->br != br)
433 spin_lock_bh(&br->lock);
434 changed_addr = br_stp_recalculate_bridge_id(br);
435 spin_unlock_bh(&br->lock);
438 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
440 netdev_update_features(br->dev);
445 void __net_exit br_net_exit(struct net *net)
447 struct net_device *dev;
451 for_each_netdev(net, dev)
452 if (dev->priv_flags & IFF_EBRIDGE)
453 br_dev_delete(dev, &list);
455 unregister_netdevice_many(&list);