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1/*
2 * Userspace interface
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/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>
25#include <net/sock.h>
26#include <linux/if_vlan.h>
27#include <net/switchdev.h>
28
29#include "br_private.h"
30
31/*
32 * Determine initial path cost based on speed.
33 * using recommendations from 802.1d standard
34 *
35 * Since driver might sleep need to not be holding any locks.
36 */
37static int port_cost(struct net_device *dev)
38{
39 struct ethtool_link_ksettings ecmd;
40
41 if (!__ethtool_get_link_ksettings(dev, &ecmd)) {
42 switch (ecmd.base.speed) {
43 case SPEED_10000:
44 return 2;
45 case SPEED_1000:
46 return 4;
47 case SPEED_100:
48 return 19;
49 case SPEED_10:
50 return 100;
51 }
52 }
53
54 /* Old silly heuristics based on name */
55 if (!strncmp(dev->name, "lec", 3))
56 return 7;
57
58 if (!strncmp(dev->name, "plip", 4))
59 return 2500;
60
61 return 100; /* assume old 10Mbps */
62}
63
64
65/* Check for port carrier transitions. */
66void br_port_carrier_check(struct net_bridge_port *p)
67{
68 struct net_device *dev = p->dev;
69 struct net_bridge *br = p->br;
70
71 if (!(p->flags & BR_ADMIN_COST) &&
72 netif_running(dev) && netif_oper_up(dev))
73 p->path_cost = port_cost(dev);
74
75 if (!netif_running(br->dev))
76 return;
77
78 spin_lock_bh(&br->lock);
79 if (netif_running(dev) && netif_oper_up(dev)) {
80 if (p->state == BR_STATE_DISABLED)
81 br_stp_enable_port(p);
82 } else {
83 if (p->state != BR_STATE_DISABLED)
84 br_stp_disable_port(p);
85 }
86 spin_unlock_bh(&br->lock);
87}
88
89static void br_port_set_promisc(struct net_bridge_port *p)
90{
91 int err = 0;
92
93 if (br_promisc_port(p))
94 return;
95
96 err = dev_set_promiscuity(p->dev, 1);
97 if (err)
98 return;
99
100 br_fdb_unsync_static(p->br, p);
101 p->flags |= BR_PROMISC;
102}
103
104static void br_port_clear_promisc(struct net_bridge_port *p)
105{
106 int err;
107
108 /* Check if the port is already non-promisc or if it doesn't
109 * support UNICAST filtering. Without unicast filtering support
110 * we'll end up re-enabling promisc mode anyway, so just check for
111 * it here.
112 */
113 if (!br_promisc_port(p) || !(p->dev->priv_flags & IFF_UNICAST_FLT))
114 return;
115
116 /* Since we'll be clearing the promisc mode, program the port
117 * first so that we don't have interruption in traffic.
118 */
119 err = br_fdb_sync_static(p->br, p);
120 if (err)
121 return;
122
123 dev_set_promiscuity(p->dev, -1);
124 p->flags &= ~BR_PROMISC;
125}
126
127/* When a port is added or removed or when certain port flags
128 * change, this function is called to automatically manage
129 * promiscuity setting of all the bridge ports. We are always called
130 * under RTNL so can skip using rcu primitives.
131 */
132void br_manage_promisc(struct net_bridge *br)
133{
134 struct net_bridge_port *p;
135 bool set_all = false;
136
137 /* If vlan filtering is disabled or bridge interface is placed
138 * into promiscuous mode, place all ports in promiscuous mode.
139 */
140 if ((br->dev->flags & IFF_PROMISC) || !br_vlan_enabled(br))
141 set_all = true;
142
143 list_for_each_entry(p, &br->port_list, list) {
144 if (set_all) {
145 br_port_set_promisc(p);
146 } else {
147 /* If the number of auto-ports is <= 1, then all other
148 * ports will have their output configuration
149 * statically specified through fdbs. Since ingress
150 * on the auto-port becomes forwarding/egress to other
151 * ports and egress configuration is statically known,
152 * we can say that ingress configuration of the
153 * auto-port is also statically known.
154 * This lets us disable promiscuous mode and write
155 * this config to hw.
156 */
157 if (br->auto_cnt == 0 ||
158 (br->auto_cnt == 1 && br_auto_port(p)))
159 br_port_clear_promisc(p);
160 else
161 br_port_set_promisc(p);
162 }
163 }
164}
165
166static void nbp_update_port_count(struct net_bridge *br)
167{
168 struct net_bridge_port *p;
169 u32 cnt = 0;
170
171 list_for_each_entry(p, &br->port_list, list) {
172 if (br_auto_port(p))
173 cnt++;
174 }
175 if (br->auto_cnt != cnt) {
176 br->auto_cnt = cnt;
177 br_manage_promisc(br);
178 }
179}
180
181static void nbp_delete_promisc(struct net_bridge_port *p)
182{
183 /* If port is currently promiscuous, unset promiscuity.
184 * Otherwise, it is a static port so remove all addresses
185 * from it.
186 */
187 dev_set_allmulti(p->dev, -1);
188 if (br_promisc_port(p))
189 dev_set_promiscuity(p->dev, -1);
190 else
191 br_fdb_unsync_static(p->br, p);
192}
193
194static void release_nbp(struct kobject *kobj)
195{
196 struct net_bridge_port *p
197 = container_of(kobj, struct net_bridge_port, kobj);
198 kfree(p);
199}
200
201static struct kobj_type brport_ktype = {
202#ifdef CONFIG_SYSFS
203 .sysfs_ops = &brport_sysfs_ops,
204#endif
205 .release = release_nbp,
206};
207
208static void destroy_nbp(struct net_bridge_port *p)
209{
210 struct net_device *dev = p->dev;
211
212 p->br = NULL;
213 p->dev = NULL;
214 dev_put(dev);
215
216 kobject_put(&p->kobj);
217}
218
219static void destroy_nbp_rcu(struct rcu_head *head)
220{
221 struct net_bridge_port *p =
222 container_of(head, struct net_bridge_port, rcu);
223 destroy_nbp(p);
224}
225
226static unsigned get_max_headroom(struct net_bridge *br)
227{
228 unsigned max_headroom = 0;
229 struct net_bridge_port *p;
230
231 list_for_each_entry(p, &br->port_list, list) {
232 unsigned dev_headroom = netdev_get_fwd_headroom(p->dev);
233
234 if (dev_headroom > max_headroom)
235 max_headroom = dev_headroom;
236 }
237
238 return max_headroom;
239}
240
241static void update_headroom(struct net_bridge *br, int new_hr)
242{
243 struct net_bridge_port *p;
244
245 list_for_each_entry(p, &br->port_list, list)
246 netdev_set_rx_headroom(p->dev, new_hr);
247
248 br->dev->needed_headroom = new_hr;
249}
250
251/* Delete port(interface) from bridge is done in two steps.
252 * via RCU. First step, marks device as down. That deletes
253 * all the timers and stops new packets from flowing through.
254 *
255 * Final cleanup doesn't occur until after all CPU's finished
256 * processing packets.
257 *
258 * Protected from multiple admin operations by RTNL mutex
259 */
260static void del_nbp(struct net_bridge_port *p)
261{
262 struct net_bridge *br = p->br;
263 struct net_device *dev = p->dev;
264
265 sysfs_remove_link(br->ifobj, p->dev->name);
266
267 nbp_delete_promisc(p);
268
269 spin_lock_bh(&br->lock);
270 br_stp_disable_port(p);
271 spin_unlock_bh(&br->lock);
272
273 br_ifinfo_notify(RTM_DELLINK, p);
274
275 list_del_rcu(&p->list);
276 if (netdev_get_fwd_headroom(dev) == br->dev->needed_headroom)
277 update_headroom(br, get_max_headroom(br));
278 netdev_reset_rx_headroom(dev);
279
280 nbp_vlan_flush(p);
281 br_fdb_delete_by_port(br, p, 0, 1);
282 switchdev_deferred_process();
283
284 nbp_update_port_count(br);
285
286 netdev_upper_dev_unlink(dev, br->dev);
287
288 dev->priv_flags &= ~IFF_BRIDGE_PORT;
289
290 netdev_rx_handler_unregister(dev);
291
292 br_multicast_del_port(p);
293
294 kobject_uevent(&p->kobj, KOBJ_REMOVE);
295 kobject_del(&p->kobj);
296
297 br_netpoll_disable(p);
298
299 call_rcu(&p->rcu, destroy_nbp_rcu);
300}
301
302/* Delete bridge device */
303void br_dev_delete(struct net_device *dev, struct list_head *head)
304{
305 struct net_bridge *br = netdev_priv(dev);
306 struct net_bridge_port *p, *n;
307
308 list_for_each_entry_safe(p, n, &br->port_list, list) {
309 del_nbp(p);
310 }
311
312 br_fdb_delete_by_port(br, NULL, 0, 1);
313
314 br_vlan_flush(br);
315 br_multicast_dev_del(br);
316 del_timer_sync(&br->gc_timer);
317
318 br_sysfs_delbr(br->dev);
319 unregister_netdevice_queue(br->dev, head);
320}
321
322/* find an available port number */
323static int find_portno(struct net_bridge *br)
324{
325 int index;
326 struct net_bridge_port *p;
327 unsigned long *inuse;
328
329 inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
330 GFP_KERNEL);
331 if (!inuse)
332 return -ENOMEM;
333
334 set_bit(0, inuse); /* zero is reserved */
335 list_for_each_entry(p, &br->port_list, list) {
336 set_bit(p->port_no, inuse);
337 }
338 index = find_first_zero_bit(inuse, BR_MAX_PORTS);
339 kfree(inuse);
340
341 return (index >= BR_MAX_PORTS) ? -EXFULL : index;
342}
343
344/* called with RTNL but without bridge lock */
345static struct net_bridge_port *new_nbp(struct net_bridge *br,
346 struct net_device *dev)
347{
348 int index;
349 struct net_bridge_port *p;
350
351 index = find_portno(br);
352 if (index < 0)
353 return ERR_PTR(index);
354
355 p = kzalloc(sizeof(*p), GFP_KERNEL);
356 if (p == NULL)
357 return ERR_PTR(-ENOMEM);
358
359 p->br = br;
360 dev_hold(dev);
361 p->dev = dev;
362 p->path_cost = port_cost(dev);
363 p->priority = 0x8000 >> BR_PORT_BITS;
364 p->port_no = index;
365 p->flags = BR_LEARNING | BR_FLOOD;
366 br_init_port(p);
367 br_set_state(p, BR_STATE_DISABLED);
368 br_stp_port_timer_init(p);
369 br_multicast_add_port(p);
370
371 return p;
372}
373
374int br_add_bridge(struct net *net, const char *name)
375{
376 struct net_device *dev;
377 int res;
378
379 dev = alloc_netdev(sizeof(struct net_bridge), name, NET_NAME_UNKNOWN,
380 br_dev_setup);
381
382 if (!dev)
383 return -ENOMEM;
384
385 dev_net_set(dev, net);
386 dev->rtnl_link_ops = &br_link_ops;
387
388 res = register_netdev(dev);
389 if (res)
390 free_netdev(dev);
391 return res;
392}
393
394int br_del_bridge(struct net *net, const char *name)
395{
396 struct net_device *dev;
397 int ret = 0;
398
399 rtnl_lock();
400 dev = __dev_get_by_name(net, name);
401 if (dev == NULL)
402 ret = -ENXIO; /* Could not find device */
403
404 else if (!(dev->priv_flags & IFF_EBRIDGE)) {
405 /* Attempt to delete non bridge device! */
406 ret = -EPERM;
407 }
408
409 else if (dev->flags & IFF_UP) {
410 /* Not shutdown yet. */
411 ret = -EBUSY;
412 }
413
414 else
415 br_dev_delete(dev, NULL);
416
417 rtnl_unlock();
418 return ret;
419}
420
421/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
422int br_min_mtu(const struct net_bridge *br)
423{
424 const struct net_bridge_port *p;
425 int mtu = 0;
426
427 ASSERT_RTNL();
428
429 if (list_empty(&br->port_list))
430 mtu = ETH_DATA_LEN;
431 else {
432 list_for_each_entry(p, &br->port_list, list) {
433 if (!mtu || p->dev->mtu < mtu)
434 mtu = p->dev->mtu;
435 }
436 }
437 return mtu;
438}
439
440static void br_set_gso_limits(struct net_bridge *br)
441{
442 unsigned int gso_max_size = GSO_MAX_SIZE;
443 u16 gso_max_segs = GSO_MAX_SEGS;
444 const struct net_bridge_port *p;
445
446 list_for_each_entry(p, &br->port_list, list) {
447 gso_max_size = min(gso_max_size, p->dev->gso_max_size);
448 gso_max_segs = min(gso_max_segs, p->dev->gso_max_segs);
449 }
450 br->dev->gso_max_size = gso_max_size;
451 br->dev->gso_max_segs = gso_max_segs;
452}
453
454/*
455 * Recomputes features using slave's features
456 */
457netdev_features_t br_features_recompute(struct net_bridge *br,
458 netdev_features_t features)
459{
460 struct net_bridge_port *p;
461 netdev_features_t mask;
462
463 if (list_empty(&br->port_list))
464 return features;
465
466 mask = features;
467 features &= ~NETIF_F_ONE_FOR_ALL;
468
469 list_for_each_entry(p, &br->port_list, list) {
470 features = netdev_increment_features(features,
471 p->dev->features, mask);
472 }
473 features = netdev_add_tso_features(features, mask);
474
475 return features;
476}
477
478/* called with RTNL */
479int br_add_if(struct net_bridge *br, struct net_device *dev)
480{
481 struct net_bridge_port *p;
482 int err = 0;
483 unsigned br_hr, dev_hr;
484 bool changed_addr;
485
486 /* Don't allow bridging non-ethernet like devices, or DSA-enabled
487 * master network devices since the bridge layer rx_handler prevents
488 * the DSA fake ethertype handler to be invoked, so we do not strip off
489 * the DSA switch tag protocol header and the bridge layer just return
490 * RX_HANDLER_CONSUMED, stopping RX processing for these frames.
491 */
492 if ((dev->flags & IFF_LOOPBACK) ||
493 dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN ||
494 !is_valid_ether_addr(dev->dev_addr) ||
495 netdev_uses_dsa(dev))
496 return -EINVAL;
497
498 /* No bridging of bridges */
499 if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
500 return -ELOOP;
501
502 /* Device is already being bridged */
503 if (br_port_exists(dev))
504 return -EBUSY;
505
506 /* No bridging devices that dislike that (e.g. wireless) */
507 if (dev->priv_flags & IFF_DONT_BRIDGE)
508 return -EOPNOTSUPP;
509
510 p = new_nbp(br, dev);
511 if (IS_ERR(p))
512 return PTR_ERR(p);
513
514 call_netdevice_notifiers(NETDEV_JOIN, dev);
515
516 err = dev_set_allmulti(dev, 1);
517 if (err)
518 goto put_back;
519
520 err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
521 SYSFS_BRIDGE_PORT_ATTR);
522 if (err)
523 goto err1;
524
525 err = br_sysfs_addif(p);
526 if (err)
527 goto err2;
528
529 err = br_netpoll_enable(p);
530 if (err)
531 goto err3;
532
533 err = netdev_rx_handler_register(dev, br_handle_frame, p);
534 if (err)
535 goto err4;
536
537 dev->priv_flags |= IFF_BRIDGE_PORT;
538
539 err = netdev_master_upper_dev_link(dev, br->dev, NULL, NULL);
540 if (err)
541 goto err5;
542
543 dev_disable_lro(dev);
544
545 list_add_rcu(&p->list, &br->port_list);
546
547 nbp_update_port_count(br);
548
549 netdev_update_features(br->dev);
550
551 br_hr = br->dev->needed_headroom;
552 dev_hr = netdev_get_fwd_headroom(dev);
553 if (br_hr < dev_hr)
554 update_headroom(br, dev_hr);
555 else
556 netdev_set_rx_headroom(dev, br_hr);
557
558 if (br_fdb_insert(br, p, dev->dev_addr, 0))
559 netdev_err(dev, "failed insert local address bridge forwarding table\n");
560
561 err = nbp_vlan_init(p);
562 if (err) {
563 netdev_err(dev, "failed to initialize vlan filtering on this port\n");
564 goto err6;
565 }
566
567 spin_lock_bh(&br->lock);
568 changed_addr = br_stp_recalculate_bridge_id(br);
569
570 if (netif_running(dev) && netif_oper_up(dev) &&
571 (br->dev->flags & IFF_UP))
572 br_stp_enable_port(p);
573 spin_unlock_bh(&br->lock);
574
575 br_ifinfo_notify(RTM_NEWLINK, p);
576
577 if (changed_addr)
578 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
579
580 dev_set_mtu(br->dev, br_min_mtu(br));
581 br_set_gso_limits(br);
582
583 kobject_uevent(&p->kobj, KOBJ_ADD);
584
585 return 0;
586
587err6:
588 list_del_rcu(&p->list);
589 br_fdb_delete_by_port(br, p, 0, 1);
590 nbp_update_port_count(br);
591 netdev_upper_dev_unlink(dev, br->dev);
592
593err5:
594 dev->priv_flags &= ~IFF_BRIDGE_PORT;
595 netdev_rx_handler_unregister(dev);
596err4:
597 br_netpoll_disable(p);
598err3:
599 sysfs_remove_link(br->ifobj, p->dev->name);
600err2:
601 kobject_put(&p->kobj);
602 p = NULL; /* kobject_put frees */
603err1:
604 dev_set_allmulti(dev, -1);
605put_back:
606 dev_put(dev);
607 kfree(p);
608 return err;
609}
610
611/* called with RTNL */
612int br_del_if(struct net_bridge *br, struct net_device *dev)
613{
614 struct net_bridge_port *p;
615 bool changed_addr;
616
617 p = br_port_get_rtnl(dev);
618 if (!p || p->br != br)
619 return -EINVAL;
620
621 /* Since more than one interface can be attached to a bridge,
622 * there still maybe an alternate path for netconsole to use;
623 * therefore there is no reason for a NETDEV_RELEASE event.
624 */
625 del_nbp(p);
626
627 dev_set_mtu(br->dev, br_min_mtu(br));
628 br_set_gso_limits(br);
629
630 spin_lock_bh(&br->lock);
631 changed_addr = br_stp_recalculate_bridge_id(br);
632 spin_unlock_bh(&br->lock);
633
634 if (changed_addr)
635 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
636
637 netdev_update_features(br->dev);
638
639 return 0;
640}
641
642void br_port_flags_change(struct net_bridge_port *p, unsigned long mask)
643{
644 struct net_bridge *br = p->br;
645
646 if (mask & BR_AUTO_MASK)
647 nbp_update_port_count(br);
648}
1/*
2 * Userspace interface
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/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>
24#include <net/sock.h>
25
26#include "br_private.h"
27
28/*
29 * Determine initial path cost based on speed.
30 * using recommendations from 802.1d standard
31 *
32 * Since driver might sleep need to not be holding any locks.
33 */
34static int port_cost(struct net_device *dev)
35{
36 if (dev->ethtool_ops && dev->ethtool_ops->get_settings) {
37 struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET, };
38
39 if (!dev_ethtool_get_settings(dev, &ecmd)) {
40 switch (ethtool_cmd_speed(&ecmd)) {
41 case SPEED_10000:
42 return 2;
43 case SPEED_1000:
44 return 4;
45 case SPEED_100:
46 return 19;
47 case SPEED_10:
48 return 100;
49 }
50 }
51 }
52
53 /* Old silly heuristics based on name */
54 if (!strncmp(dev->name, "lec", 3))
55 return 7;
56
57 if (!strncmp(dev->name, "plip", 4))
58 return 2500;
59
60 return 100; /* assume old 10Mbps */
61}
62
63
64/* Check for port carrier transistions. */
65void br_port_carrier_check(struct net_bridge_port *p)
66{
67 struct net_device *dev = p->dev;
68 struct net_bridge *br = p->br;
69
70 if (netif_running(dev) && netif_carrier_ok(dev))
71 p->path_cost = port_cost(dev);
72
73 if (!netif_running(br->dev))
74 return;
75
76 spin_lock_bh(&br->lock);
77 if (netif_running(dev) && netif_carrier_ok(dev)) {
78 if (p->state == BR_STATE_DISABLED)
79 br_stp_enable_port(p);
80 } else {
81 if (p->state != BR_STATE_DISABLED)
82 br_stp_disable_port(p);
83 }
84 spin_unlock_bh(&br->lock);
85}
86
87static void release_nbp(struct kobject *kobj)
88{
89 struct net_bridge_port *p
90 = container_of(kobj, struct net_bridge_port, kobj);
91 kfree(p);
92}
93
94static struct kobj_type brport_ktype = {
95#ifdef CONFIG_SYSFS
96 .sysfs_ops = &brport_sysfs_ops,
97#endif
98 .release = release_nbp,
99};
100
101static void destroy_nbp(struct net_bridge_port *p)
102{
103 struct net_device *dev = p->dev;
104
105 p->br = NULL;
106 p->dev = NULL;
107 dev_put(dev);
108
109 kobject_put(&p->kobj);
110}
111
112static void destroy_nbp_rcu(struct rcu_head *head)
113{
114 struct net_bridge_port *p =
115 container_of(head, struct net_bridge_port, rcu);
116 destroy_nbp(p);
117}
118
119/* Delete port(interface) from bridge is done in two steps.
120 * via RCU. First step, marks device as down. That deletes
121 * all the timers and stops new packets from flowing through.
122 *
123 * Final cleanup doesn't occur until after all CPU's finished
124 * processing packets.
125 *
126 * Protected from multiple admin operations by RTNL mutex
127 */
128static void del_nbp(struct net_bridge_port *p)
129{
130 struct net_bridge *br = p->br;
131 struct net_device *dev = p->dev;
132
133 sysfs_remove_link(br->ifobj, p->dev->name);
134
135 dev_set_promiscuity(dev, -1);
136
137 spin_lock_bh(&br->lock);
138 br_stp_disable_port(p);
139 spin_unlock_bh(&br->lock);
140
141 br_ifinfo_notify(RTM_DELLINK, p);
142
143 br_fdb_delete_by_port(br, p, 1);
144
145 list_del_rcu(&p->list);
146
147 dev->priv_flags &= ~IFF_BRIDGE_PORT;
148
149 netdev_rx_handler_unregister(dev);
150 synchronize_net();
151
152 netdev_set_master(dev, NULL);
153
154 br_multicast_del_port(p);
155
156 kobject_uevent(&p->kobj, KOBJ_REMOVE);
157 kobject_del(&p->kobj);
158
159 br_netpoll_disable(p);
160
161 call_rcu(&p->rcu, destroy_nbp_rcu);
162}
163
164/* Delete bridge device */
165void br_dev_delete(struct net_device *dev, struct list_head *head)
166{
167 struct net_bridge *br = netdev_priv(dev);
168 struct net_bridge_port *p, *n;
169
170 list_for_each_entry_safe(p, n, &br->port_list, list) {
171 del_nbp(p);
172 }
173
174 del_timer_sync(&br->gc_timer);
175
176 br_sysfs_delbr(br->dev);
177 unregister_netdevice_queue(br->dev, head);
178}
179
180/* find an available port number */
181static int find_portno(struct net_bridge *br)
182{
183 int index;
184 struct net_bridge_port *p;
185 unsigned long *inuse;
186
187 inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
188 GFP_KERNEL);
189 if (!inuse)
190 return -ENOMEM;
191
192 set_bit(0, inuse); /* zero is reserved */
193 list_for_each_entry(p, &br->port_list, list) {
194 set_bit(p->port_no, inuse);
195 }
196 index = find_first_zero_bit(inuse, BR_MAX_PORTS);
197 kfree(inuse);
198
199 return (index >= BR_MAX_PORTS) ? -EXFULL : index;
200}
201
202/* called with RTNL but without bridge lock */
203static struct net_bridge_port *new_nbp(struct net_bridge *br,
204 struct net_device *dev)
205{
206 int index;
207 struct net_bridge_port *p;
208
209 index = find_portno(br);
210 if (index < 0)
211 return ERR_PTR(index);
212
213 p = kzalloc(sizeof(*p), GFP_KERNEL);
214 if (p == NULL)
215 return ERR_PTR(-ENOMEM);
216
217 p->br = br;
218 dev_hold(dev);
219 p->dev = dev;
220 p->path_cost = port_cost(dev);
221 p->priority = 0x8000 >> BR_PORT_BITS;
222 p->port_no = index;
223 p->flags = 0;
224 br_init_port(p);
225 p->state = BR_STATE_DISABLED;
226 br_stp_port_timer_init(p);
227 br_multicast_add_port(p);
228
229 return p;
230}
231
232int br_add_bridge(struct net *net, const char *name)
233{
234 struct net_device *dev;
235 int res;
236
237 dev = alloc_netdev(sizeof(struct net_bridge), name,
238 br_dev_setup);
239
240 if (!dev)
241 return -ENOMEM;
242
243 dev_net_set(dev, net);
244
245 res = register_netdev(dev);
246 if (res)
247 free_netdev(dev);
248 return res;
249}
250
251int br_del_bridge(struct net *net, const char *name)
252{
253 struct net_device *dev;
254 int ret = 0;
255
256 rtnl_lock();
257 dev = __dev_get_by_name(net, name);
258 if (dev == NULL)
259 ret = -ENXIO; /* Could not find device */
260
261 else if (!(dev->priv_flags & IFF_EBRIDGE)) {
262 /* Attempt to delete non bridge device! */
263 ret = -EPERM;
264 }
265
266 else if (dev->flags & IFF_UP) {
267 /* Not shutdown yet. */
268 ret = -EBUSY;
269 }
270
271 else
272 br_dev_delete(dev, NULL);
273
274 rtnl_unlock();
275 return ret;
276}
277
278/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
279int br_min_mtu(const struct net_bridge *br)
280{
281 const struct net_bridge_port *p;
282 int mtu = 0;
283
284 ASSERT_RTNL();
285
286 if (list_empty(&br->port_list))
287 mtu = ETH_DATA_LEN;
288 else {
289 list_for_each_entry(p, &br->port_list, list) {
290 if (!mtu || p->dev->mtu < mtu)
291 mtu = p->dev->mtu;
292 }
293 }
294 return mtu;
295}
296
297/*
298 * Recomputes features using slave's features
299 */
300u32 br_features_recompute(struct net_bridge *br, u32 features)
301{
302 struct net_bridge_port *p;
303 u32 mask;
304
305 if (list_empty(&br->port_list))
306 return features;
307
308 mask = features;
309 features &= ~NETIF_F_ONE_FOR_ALL;
310
311 list_for_each_entry(p, &br->port_list, list) {
312 features = netdev_increment_features(features,
313 p->dev->features, mask);
314 }
315
316 return features;
317}
318
319/* called with RTNL */
320int br_add_if(struct net_bridge *br, struct net_device *dev)
321{
322 struct net_bridge_port *p;
323 int err = 0;
324 bool changed_addr;
325
326 /* Don't allow bridging non-ethernet like devices */
327 if ((dev->flags & IFF_LOOPBACK) ||
328 dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN)
329 return -EINVAL;
330
331 /* No bridging of bridges */
332 if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
333 return -ELOOP;
334
335 /* Device is already being bridged */
336 if (br_port_exists(dev))
337 return -EBUSY;
338
339 /* No bridging devices that dislike that (e.g. wireless) */
340 if (dev->priv_flags & IFF_DONT_BRIDGE)
341 return -EOPNOTSUPP;
342
343 p = new_nbp(br, dev);
344 if (IS_ERR(p))
345 return PTR_ERR(p);
346
347 call_netdevice_notifiers(NETDEV_JOIN, dev);
348
349 err = dev_set_promiscuity(dev, 1);
350 if (err)
351 goto put_back;
352
353 err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
354 SYSFS_BRIDGE_PORT_ATTR);
355 if (err)
356 goto err0;
357
358 err = br_fdb_insert(br, p, dev->dev_addr);
359 if (err)
360 goto err1;
361
362 err = br_sysfs_addif(p);
363 if (err)
364 goto err2;
365
366 if (br_netpoll_info(br) && ((err = br_netpoll_enable(p))))
367 goto err3;
368
369 err = netdev_set_master(dev, br->dev);
370 if (err)
371 goto err3;
372
373 err = netdev_rx_handler_register(dev, br_handle_frame, p);
374 if (err)
375 goto err4;
376
377 dev->priv_flags |= IFF_BRIDGE_PORT;
378
379 dev_disable_lro(dev);
380
381 list_add_rcu(&p->list, &br->port_list);
382
383 netdev_update_features(br->dev);
384
385 spin_lock_bh(&br->lock);
386 changed_addr = br_stp_recalculate_bridge_id(br);
387
388 if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) &&
389 (br->dev->flags & IFF_UP))
390 br_stp_enable_port(p);
391 spin_unlock_bh(&br->lock);
392
393 br_ifinfo_notify(RTM_NEWLINK, p);
394
395 if (changed_addr)
396 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
397
398 dev_set_mtu(br->dev, br_min_mtu(br));
399
400 kobject_uevent(&p->kobj, KOBJ_ADD);
401
402 return 0;
403
404err4:
405 netdev_set_master(dev, NULL);
406err3:
407 sysfs_remove_link(br->ifobj, p->dev->name);
408err2:
409 br_fdb_delete_by_port(br, p, 1);
410err1:
411 kobject_put(&p->kobj);
412 p = NULL; /* kobject_put frees */
413err0:
414 dev_set_promiscuity(dev, -1);
415put_back:
416 dev_put(dev);
417 kfree(p);
418 return err;
419}
420
421/* called with RTNL */
422int br_del_if(struct net_bridge *br, struct net_device *dev)
423{
424 struct net_bridge_port *p;
425 bool changed_addr;
426
427 p = br_port_get_rtnl(dev);
428 if (!p || p->br != br)
429 return -EINVAL;
430
431 del_nbp(p);
432
433 spin_lock_bh(&br->lock);
434 changed_addr = br_stp_recalculate_bridge_id(br);
435 spin_unlock_bh(&br->lock);
436
437 if (changed_addr)
438 call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
439
440 netdev_update_features(br->dev);
441
442 return 0;
443}
444
445void __net_exit br_net_exit(struct net *net)
446{
447 struct net_device *dev;
448 LIST_HEAD(list);
449
450 rtnl_lock();
451 for_each_netdev(net, dev)
452 if (dev->priv_flags & IFF_EBRIDGE)
453 br_dev_delete(dev, &list);
454
455 unregister_netdevice_many(&list);
456 rtnl_unlock();
457
458}