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/netpoll.h>
17 #include <linux/ethtool.h>
18 #include <linux/if_arp.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/rtnetlink.h>
22 #include <linux/if_ether.h>
23 #include <linux/slab.h>
26 #include "br_private.h"
29 * Determine initial path cost based on speed.
30 * using recommendations from 802.1d standard
32 * Since driver might sleep need to not be holding any locks.
34 static int port_cost(struct net_device *dev)
36 if (dev->ethtool_ops && dev->ethtool_ops->get_settings) {
37 struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET, };
39 if (!dev->ethtool_ops->get_settings(dev, &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 */
65 * Check for port carrier transistions.
66 * Called from work queue to allow for calling functions that
67 * might sleep (such as speed check), and to debounce.
69 void br_port_carrier_check(struct net_bridge_port *p)
71 struct net_device *dev = p->dev;
72 struct net_bridge *br = p->br;
74 if (netif_carrier_ok(dev))
75 p->path_cost = port_cost(dev);
77 if (netif_running(br->dev)) {
78 spin_lock_bh(&br->lock);
79 if (netif_carrier_ok(dev)) {
80 if (p->state == BR_STATE_DISABLED)
81 br_stp_enable_port(p);
83 if (p->state != BR_STATE_DISABLED)
84 br_stp_disable_port(p);
86 spin_unlock_bh(&br->lock);
90 static void release_nbp(struct kobject *kobj)
92 struct net_bridge_port *p
93 = container_of(kobj, struct net_bridge_port, kobj);
97 static struct kobj_type brport_ktype = {
99 .sysfs_ops = &brport_sysfs_ops,
101 .release = release_nbp,
104 static void destroy_nbp(struct net_bridge_port *p)
106 struct net_device *dev = p->dev;
112 kobject_put(&p->kobj);
115 static void destroy_nbp_rcu(struct rcu_head *head)
117 struct net_bridge_port *p =
118 container_of(head, struct net_bridge_port, rcu);
122 /* Delete port(interface) from bridge is done in two steps.
123 * via RCU. First step, marks device as down. That deletes
124 * all the timers and stops new packets from flowing through.
126 * Final cleanup doesn't occur until after all CPU's finished
127 * processing packets.
129 * Protected from multiple admin operations by RTNL mutex
131 static void del_nbp(struct net_bridge_port *p)
133 struct net_bridge *br = p->br;
134 struct net_device *dev = p->dev;
136 sysfs_remove_link(br->ifobj, dev->name);
138 dev_set_promiscuity(dev, -1);
140 spin_lock_bh(&br->lock);
141 br_stp_disable_port(p);
142 spin_unlock_bh(&br->lock);
144 br_ifinfo_notify(RTM_DELLINK, p);
146 br_fdb_delete_by_port(br, p, 1);
148 list_del_rcu(&p->list);
150 rcu_assign_pointer(dev->br_port, NULL);
152 br_multicast_del_port(p);
154 kobject_uevent(&p->kobj, KOBJ_REMOVE);
155 kobject_del(&p->kobj);
157 #ifdef CONFIG_NET_POLL_CONTROLLER
158 if (br_devices_support_netpoll(br))
159 br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
160 if (dev->netdev_ops->ndo_netpoll_cleanup)
161 dev->netdev_ops->ndo_netpoll_cleanup(dev);
165 call_rcu(&p->rcu, destroy_nbp_rcu);
168 /* called with RTNL */
169 static void del_br(struct net_bridge *br, struct list_head *head)
171 struct net_bridge_port *p, *n;
173 list_for_each_entry_safe(p, n, &br->port_list, list) {
177 br_netpoll_cleanup(br->dev);
179 del_timer_sync(&br->gc_timer);
181 br_sysfs_delbr(br->dev);
182 unregister_netdevice_queue(br->dev, head);
185 static struct net_device *new_bridge_dev(struct net *net, const char *name)
187 struct net_bridge *br;
188 struct net_device *dev;
190 dev = alloc_netdev(sizeof(struct net_bridge), name,
195 dev_net_set(dev, net);
197 br = netdev_priv(dev);
200 br->stats = alloc_percpu(struct br_cpu_netstats);
206 spin_lock_init(&br->lock);
207 INIT_LIST_HEAD(&br->port_list);
208 spin_lock_init(&br->hash_lock);
210 br->bridge_id.prio[0] = 0x80;
211 br->bridge_id.prio[1] = 0x00;
213 memcpy(br->group_addr, br_group_address, ETH_ALEN);
215 br->feature_mask = dev->features;
216 br->stp_enabled = BR_NO_STP;
217 br->designated_root = br->bridge_id;
218 br->root_path_cost = 0;
220 br->bridge_max_age = br->max_age = 20 * HZ;
221 br->bridge_hello_time = br->hello_time = 2 * HZ;
222 br->bridge_forward_delay = br->forward_delay = 15 * HZ;
223 br->topology_change = 0;
224 br->topology_change_detected = 0;
225 br->ageing_time = 300 * HZ;
227 br_netfilter_rtable_init(br);
229 br_stp_timer_init(br);
230 br_multicast_init(br);
235 /* find an available port number */
236 static int find_portno(struct net_bridge *br)
239 struct net_bridge_port *p;
240 unsigned long *inuse;
242 inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
247 set_bit(0, inuse); /* zero is reserved */
248 list_for_each_entry(p, &br->port_list, list) {
249 set_bit(p->port_no, inuse);
251 index = find_first_zero_bit(inuse, BR_MAX_PORTS);
254 return (index >= BR_MAX_PORTS) ? -EXFULL : index;
257 /* called with RTNL but without bridge lock */
258 static struct net_bridge_port *new_nbp(struct net_bridge *br,
259 struct net_device *dev)
262 struct net_bridge_port *p;
264 index = find_portno(br);
266 return ERR_PTR(index);
268 p = kzalloc(sizeof(*p), GFP_KERNEL);
270 return ERR_PTR(-ENOMEM);
275 p->path_cost = port_cost(dev);
276 p->priority = 0x8000 >> BR_PORT_BITS;
280 p->state = BR_STATE_DISABLED;
281 br_stp_port_timer_init(p);
282 br_multicast_add_port(p);
287 static struct device_type br_type = {
291 int br_add_bridge(struct net *net, const char *name)
293 struct net_device *dev;
296 dev = new_bridge_dev(net, name);
301 if (strchr(dev->name, '%')) {
302 ret = dev_alloc_name(dev, dev->name);
307 SET_NETDEV_DEVTYPE(dev, &br_type);
309 ret = register_netdevice(dev);
313 ret = br_sysfs_addbr(dev);
315 unregister_netdevice(dev);
325 int br_del_bridge(struct net *net, const char *name)
327 struct net_device *dev;
331 dev = __dev_get_by_name(net, name);
333 ret = -ENXIO; /* Could not find device */
335 else if (!(dev->priv_flags & IFF_EBRIDGE)) {
336 /* Attempt to delete non bridge device! */
340 else if (dev->flags & IFF_UP) {
341 /* Not shutdown yet. */
346 del_br(netdev_priv(dev), NULL);
352 /* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
353 int br_min_mtu(const struct net_bridge *br)
355 const struct net_bridge_port *p;
360 if (list_empty(&br->port_list))
363 list_for_each_entry(p, &br->port_list, list) {
364 if (!mtu || p->dev->mtu < mtu)
372 * Recomputes features using slave's features
374 void br_features_recompute(struct net_bridge *br)
376 struct net_bridge_port *p;
377 unsigned long features, mask;
379 features = mask = br->feature_mask;
380 if (list_empty(&br->port_list))
383 features &= ~NETIF_F_ONE_FOR_ALL;
385 list_for_each_entry(p, &br->port_list, list) {
386 features = netdev_increment_features(features,
387 p->dev->features, mask);
391 br->dev->features = netdev_fix_features(features, NULL);
394 /* called with RTNL */
395 int br_add_if(struct net_bridge *br, struct net_device *dev)
397 struct net_bridge_port *p;
400 /* Don't allow bridging non-ethernet like devices */
401 if ((dev->flags & IFF_LOOPBACK) ||
402 dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN)
405 /* No bridging of bridges */
406 if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
409 /* Device is already being bridged */
410 if (dev->br_port != NULL)
413 /* No bridging devices that dislike that (e.g. wireless) */
414 if (dev->priv_flags & IFF_DONT_BRIDGE)
417 p = new_nbp(br, dev);
421 err = dev_set_promiscuity(dev, 1);
425 err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
426 SYSFS_BRIDGE_PORT_ATTR);
430 err = br_fdb_insert(br, p, dev->dev_addr);
434 err = br_sysfs_addif(p);
438 rcu_assign_pointer(dev->br_port, p);
439 dev_disable_lro(dev);
441 list_add_rcu(&p->list, &br->port_list);
443 spin_lock_bh(&br->lock);
444 br_stp_recalculate_bridge_id(br);
445 br_features_recompute(br);
447 if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) &&
448 (br->dev->flags & IFF_UP))
449 br_stp_enable_port(p);
450 spin_unlock_bh(&br->lock);
452 br_ifinfo_notify(RTM_NEWLINK, p);
454 dev_set_mtu(br->dev, br_min_mtu(br));
456 kobject_uevent(&p->kobj, KOBJ_ADD);
458 #ifdef CONFIG_NET_POLL_CONTROLLER
459 if (br_devices_support_netpoll(br)) {
460 br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
462 dev->npinfo = br->dev->npinfo;
463 } else if (!(br->dev->priv_flags & IFF_DISABLE_NETPOLL)) {
464 br->dev->priv_flags |= IFF_DISABLE_NETPOLL;
465 printk(KERN_INFO "New device %s does not support netpoll\n",
467 printk(KERN_INFO "Disabling netpoll for %s\n",
474 br_fdb_delete_by_port(br, p, 1);
476 kobject_put(&p->kobj);
477 p = NULL; /* kobject_put frees */
479 dev_set_promiscuity(dev, -1);
486 /* called with RTNL */
487 int br_del_if(struct net_bridge *br, struct net_device *dev)
489 struct net_bridge_port *p = dev->br_port;
491 if (!p || p->br != br)
496 spin_lock_bh(&br->lock);
497 br_stp_recalculate_bridge_id(br);
498 br_features_recompute(br);
499 spin_unlock_bh(&br->lock);
504 void __net_exit br_net_exit(struct net *net)
506 struct net_device *dev;
510 for_each_netdev(net, dev)
511 if (dev->priv_flags & IFF_EBRIDGE)
512 del_br(netdev_priv(dev), &list);
514 unregister_netdevice_many(&list);