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v4.6
  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}
v3.15
  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
 28#include "br_private.h"
 29
 30/*
 31 * Determine initial path cost based on speed.
 32 * using recommendations from 802.1d standard
 33 *
 34 * Since driver might sleep need to not be holding any locks.
 35 */
 36static int port_cost(struct net_device *dev)
 37{
 38	struct ethtool_cmd ecmd;
 39
 40	if (!__ethtool_get_settings(dev, &ecmd)) {
 41		switch (ethtool_cmd_speed(&ecmd)) {
 42		case SPEED_10000:
 43			return 2;
 44		case SPEED_1000:
 45			return 4;
 46		case SPEED_100:
 47			return 19;
 48		case SPEED_10:
 49			return 100;
 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 transitions. */
 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 (!(p->flags & BR_ADMIN_COST) &&
 71	    netif_running(dev) && netif_oper_up(dev))
 72		p->path_cost = port_cost(dev);
 73
 74	if (!netif_running(br->dev))
 75		return;
 76
 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);
 81	} else {
 82		if (p->state != BR_STATE_DISABLED)
 83			br_stp_disable_port(p);
 84	}
 85	spin_unlock_bh(&br->lock);
 86}
 87
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 88static void release_nbp(struct kobject *kobj)
 89{
 90	struct net_bridge_port *p
 91		= container_of(kobj, struct net_bridge_port, kobj);
 92	kfree(p);
 93}
 94
 95static struct kobj_type brport_ktype = {
 96#ifdef CONFIG_SYSFS
 97	.sysfs_ops = &brport_sysfs_ops,
 98#endif
 99	.release = release_nbp,
100};
101
102static void destroy_nbp(struct net_bridge_port *p)
103{
104	struct net_device *dev = p->dev;
105
106	p->br = NULL;
107	p->dev = NULL;
108	dev_put(dev);
109
110	kobject_put(&p->kobj);
111}
112
113static void destroy_nbp_rcu(struct rcu_head *head)
114{
115	struct net_bridge_port *p =
116			container_of(head, struct net_bridge_port, rcu);
117	destroy_nbp(p);
118}
119
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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.
123 *
124 * Final cleanup doesn't occur until after all CPU's finished
125 * processing packets.
126 *
127 * Protected from multiple admin operations by RTNL mutex
128 */
129static void del_nbp(struct net_bridge_port *p)
130{
131	struct net_bridge *br = p->br;
132	struct net_device *dev = p->dev;
133
134	sysfs_remove_link(br->ifobj, p->dev->name);
135
136	dev_set_promiscuity(dev, -1);
137
138	spin_lock_bh(&br->lock);
139	br_stp_disable_port(p);
140	spin_unlock_bh(&br->lock);
141
142	br_ifinfo_notify(RTM_DELLINK, p);
143
 
 
 
 
 
144	nbp_vlan_flush(p);
145	br_fdb_delete_by_port(br, p, 1);
 
146
147	list_del_rcu(&p->list);
 
 
148
149	dev->priv_flags &= ~IFF_BRIDGE_PORT;
150
151	netdev_rx_handler_unregister(dev);
152
153	netdev_upper_dev_unlink(dev, br->dev);
154
155	br_multicast_del_port(p);
156
157	kobject_uevent(&p->kobj, KOBJ_REMOVE);
158	kobject_del(&p->kobj);
159
160	br_netpoll_disable(p);
161
162	call_rcu(&p->rcu, destroy_nbp_rcu);
163}
164
165/* Delete bridge device */
166void br_dev_delete(struct net_device *dev, struct list_head *head)
167{
168	struct net_bridge *br = netdev_priv(dev);
169	struct net_bridge_port *p, *n;
170
171	list_for_each_entry_safe(p, n, &br->port_list, list) {
172		del_nbp(p);
173	}
174
175	br_fdb_delete_by_port(br, NULL, 1);
176
177	br_vlan_flush(br);
 
178	del_timer_sync(&br->gc_timer);
179
180	br_sysfs_delbr(br->dev);
181	unregister_netdevice_queue(br->dev, head);
182}
183
184/* find an available port number */
185static int find_portno(struct net_bridge *br)
186{
187	int index;
188	struct net_bridge_port *p;
189	unsigned long *inuse;
190
191	inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
192			GFP_KERNEL);
193	if (!inuse)
194		return -ENOMEM;
195
196	set_bit(0, inuse);	/* zero is reserved */
197	list_for_each_entry(p, &br->port_list, list) {
198		set_bit(p->port_no, inuse);
199	}
200	index = find_first_zero_bit(inuse, BR_MAX_PORTS);
201	kfree(inuse);
202
203	return (index >= BR_MAX_PORTS) ? -EXFULL : index;
204}
205
206/* called with RTNL but without bridge lock */
207static struct net_bridge_port *new_nbp(struct net_bridge *br,
208				       struct net_device *dev)
209{
210	int index;
211	struct net_bridge_port *p;
212
213	index = find_portno(br);
214	if (index < 0)
215		return ERR_PTR(index);
216
217	p = kzalloc(sizeof(*p), GFP_KERNEL);
218	if (p == NULL)
219		return ERR_PTR(-ENOMEM);
220
221	p->br = br;
222	dev_hold(dev);
223	p->dev = dev;
224	p->path_cost = port_cost(dev);
225	p->priority = 0x8000 >> BR_PORT_BITS;
226	p->port_no = index;
227	p->flags = BR_LEARNING | BR_FLOOD;
228	br_init_port(p);
229	p->state = BR_STATE_DISABLED;
230	br_stp_port_timer_init(p);
231	br_multicast_add_port(p);
232
233	return p;
234}
235
236int br_add_bridge(struct net *net, const char *name)
237{
238	struct net_device *dev;
239	int res;
240
241	dev = alloc_netdev(sizeof(struct net_bridge), name,
242			   br_dev_setup);
243
244	if (!dev)
245		return -ENOMEM;
246
247	dev_net_set(dev, net);
248	dev->rtnl_link_ops = &br_link_ops;
249
250	res = register_netdev(dev);
251	if (res)
252		free_netdev(dev);
253	return res;
254}
255
256int br_del_bridge(struct net *net, const char *name)
257{
258	struct net_device *dev;
259	int ret = 0;
260
261	rtnl_lock();
262	dev = __dev_get_by_name(net, name);
263	if (dev == NULL)
264		ret =  -ENXIO; 	/* Could not find device */
265
266	else if (!(dev->priv_flags & IFF_EBRIDGE)) {
267		/* Attempt to delete non bridge device! */
268		ret = -EPERM;
269	}
270
271	else if (dev->flags & IFF_UP) {
272		/* Not shutdown yet. */
273		ret = -EBUSY;
274	}
275
276	else
277		br_dev_delete(dev, NULL);
278
279	rtnl_unlock();
280	return ret;
281}
282
283/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
284int br_min_mtu(const struct net_bridge *br)
285{
286	const struct net_bridge_port *p;
287	int mtu = 0;
288
289	ASSERT_RTNL();
290
291	if (list_empty(&br->port_list))
292		mtu = ETH_DATA_LEN;
293	else {
294		list_for_each_entry(p, &br->port_list, list) {
295			if (!mtu  || p->dev->mtu < mtu)
296				mtu = p->dev->mtu;
297		}
298	}
299	return mtu;
300}
301
 
 
 
 
 
 
 
 
 
 
 
 
 
 
302/*
303 * Recomputes features using slave's features
304 */
305netdev_features_t br_features_recompute(struct net_bridge *br,
306	netdev_features_t features)
307{
308	struct net_bridge_port *p;
309	netdev_features_t mask;
310
311	if (list_empty(&br->port_list))
312		return features;
313
314	mask = features;
315	features &= ~NETIF_F_ONE_FOR_ALL;
316
317	list_for_each_entry(p, &br->port_list, list) {
318		features = netdev_increment_features(features,
319						     p->dev->features, mask);
320	}
 
321
322	return features;
323}
324
325/* called with RTNL */
326int br_add_if(struct net_bridge *br, struct net_device *dev)
327{
328	struct net_bridge_port *p;
329	int err = 0;
 
330	bool changed_addr;
331
332	/* Don't allow bridging non-ethernet like devices */
 
 
 
 
 
333	if ((dev->flags & IFF_LOOPBACK) ||
334	    dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN ||
335	    !is_valid_ether_addr(dev->dev_addr))
 
336		return -EINVAL;
337
338	/* No bridging of bridges */
339	if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
340		return -ELOOP;
341
342	/* Device is already being bridged */
343	if (br_port_exists(dev))
344		return -EBUSY;
345
346	/* No bridging devices that dislike that (e.g. wireless) */
347	if (dev->priv_flags & IFF_DONT_BRIDGE)
348		return -EOPNOTSUPP;
349
350	p = new_nbp(br, dev);
351	if (IS_ERR(p))
352		return PTR_ERR(p);
353
354	call_netdevice_notifiers(NETDEV_JOIN, dev);
355
356	err = dev_set_promiscuity(dev, 1);
357	if (err)
358		goto put_back;
359
360	err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
361				   SYSFS_BRIDGE_PORT_ATTR);
362	if (err)
363		goto err1;
364
365	err = br_sysfs_addif(p);
366	if (err)
367		goto err2;
368
369	err = br_netpoll_enable(p);
370	if (err)
371		goto err3;
372
373	err = netdev_master_upper_dev_link(dev, br->dev);
374	if (err)
375		goto err4;
376
377	err = netdev_rx_handler_register(dev, br_handle_frame, p);
 
 
378	if (err)
379		goto err5;
380
381	dev->priv_flags |= IFF_BRIDGE_PORT;
382
383	dev_disable_lro(dev);
384
385	list_add_rcu(&p->list, &br->port_list);
386
 
 
387	netdev_update_features(br->dev);
388
389	if (br->dev->needed_headroom < dev->needed_headroom)
390		br->dev->needed_headroom = dev->needed_headroom;
 
 
 
 
391
392	if (br_fdb_insert(br, p, dev->dev_addr, 0))
393		netdev_err(dev, "failed insert local address bridge forwarding table\n");
394
 
 
 
 
 
 
395	spin_lock_bh(&br->lock);
396	changed_addr = br_stp_recalculate_bridge_id(br);
397
398	if (netif_running(dev) && netif_oper_up(dev) &&
399	    (br->dev->flags & IFF_UP))
400		br_stp_enable_port(p);
401	spin_unlock_bh(&br->lock);
402
403	br_ifinfo_notify(RTM_NEWLINK, p);
404
405	if (changed_addr)
406		call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
407
408	dev_set_mtu(br->dev, br_min_mtu(br));
 
409
410	kobject_uevent(&p->kobj, KOBJ_ADD);
411
412	return 0;
413
 
 
 
 
 
 
414err5:
415	netdev_upper_dev_unlink(dev, br->dev);
 
416err4:
417	br_netpoll_disable(p);
418err3:
419	sysfs_remove_link(br->ifobj, p->dev->name);
420err2:
421	kobject_put(&p->kobj);
422	p = NULL; /* kobject_put frees */
423err1:
424	dev_set_promiscuity(dev, -1);
425put_back:
426	dev_put(dev);
427	kfree(p);
428	return err;
429}
430
431/* called with RTNL */
432int br_del_if(struct net_bridge *br, struct net_device *dev)
433{
434	struct net_bridge_port *p;
435	bool changed_addr;
436
437	p = br_port_get_rtnl(dev);
438	if (!p || p->br != br)
439		return -EINVAL;
440
441	/* Since more than one interface can be attached to a bridge,
442	 * there still maybe an alternate path for netconsole to use;
443	 * therefore there is no reason for a NETDEV_RELEASE event.
444	 */
445	del_nbp(p);
446
 
 
 
447	spin_lock_bh(&br->lock);
448	changed_addr = br_stp_recalculate_bridge_id(br);
449	spin_unlock_bh(&br->lock);
450
451	if (changed_addr)
452		call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
453
454	netdev_update_features(br->dev);
455
456	return 0;
 
 
 
 
 
 
 
 
457}