Linux Audio

Check our new training course

Buildroot integration, development and maintenance

Need a Buildroot system for your embedded project?
Loading...
v3.1
  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}
v4.10.11
  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	struct net_bridge_port *p;
349	int index, err;
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 | BR_MCAST_FLOOD;
366	br_init_port(p);
367	br_set_state(p, BR_STATE_DISABLED);
368	br_stp_port_timer_init(p);
369	err = br_multicast_add_port(p);
370	if (err) {
371		dev_put(dev);
372		kfree(p);
373		p = ERR_PTR(err);
374	}
375
376	return p;
377}
378
379int br_add_bridge(struct net *net, const char *name)
380{
381	struct net_device *dev;
382	int res;
383
384	dev = alloc_netdev(sizeof(struct net_bridge), name, NET_NAME_UNKNOWN,
385			   br_dev_setup);
386
387	if (!dev)
388		return -ENOMEM;
389
390	dev_net_set(dev, net);
391	dev->rtnl_link_ops = &br_link_ops;
392
393	res = register_netdev(dev);
394	if (res)
395		free_netdev(dev);
396	return res;
397}
398
399int br_del_bridge(struct net *net, const char *name)
400{
401	struct net_device *dev;
402	int ret = 0;
403
404	rtnl_lock();
405	dev = __dev_get_by_name(net, name);
406	if (dev == NULL)
407		ret =  -ENXIO; 	/* Could not find device */
408
409	else if (!(dev->priv_flags & IFF_EBRIDGE)) {
410		/* Attempt to delete non bridge device! */
411		ret = -EPERM;
412	}
413
414	else if (dev->flags & IFF_UP) {
415		/* Not shutdown yet. */
416		ret = -EBUSY;
417	}
418
419	else
420		br_dev_delete(dev, NULL);
421
422	rtnl_unlock();
423	return ret;
424}
425
426/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
427int br_min_mtu(const struct net_bridge *br)
428{
429	const struct net_bridge_port *p;
430	int mtu = 0;
431
432	ASSERT_RTNL();
433
434	if (list_empty(&br->port_list))
435		mtu = ETH_DATA_LEN;
436	else {
437		list_for_each_entry(p, &br->port_list, list) {
438			if (!mtu  || p->dev->mtu < mtu)
439				mtu = p->dev->mtu;
440		}
441	}
442	return mtu;
443}
444
445static void br_set_gso_limits(struct net_bridge *br)
446{
447	unsigned int gso_max_size = GSO_MAX_SIZE;
448	u16 gso_max_segs = GSO_MAX_SEGS;
449	const struct net_bridge_port *p;
450
451	list_for_each_entry(p, &br->port_list, list) {
452		gso_max_size = min(gso_max_size, p->dev->gso_max_size);
453		gso_max_segs = min(gso_max_segs, p->dev->gso_max_segs);
454	}
455	br->dev->gso_max_size = gso_max_size;
456	br->dev->gso_max_segs = gso_max_segs;
457}
458
459/*
460 * Recomputes features using slave's features
461 */
462netdev_features_t br_features_recompute(struct net_bridge *br,
463	netdev_features_t features)
464{
465	struct net_bridge_port *p;
466	netdev_features_t mask;
467
468	if (list_empty(&br->port_list))
469		return features;
470
471	mask = features;
472	features &= ~NETIF_F_ONE_FOR_ALL;
473
474	list_for_each_entry(p, &br->port_list, list) {
475		features = netdev_increment_features(features,
476						     p->dev->features, mask);
477	}
478	features = netdev_add_tso_features(features, mask);
479
480	return features;
481}
482
483/* called with RTNL */
484int br_add_if(struct net_bridge *br, struct net_device *dev)
485{
486	struct net_bridge_port *p;
487	int err = 0;
488	unsigned br_hr, dev_hr;
489	bool changed_addr;
490
491	/* Don't allow bridging non-ethernet like devices, or DSA-enabled
492	 * master network devices since the bridge layer rx_handler prevents
493	 * the DSA fake ethertype handler to be invoked, so we do not strip off
494	 * the DSA switch tag protocol header and the bridge layer just return
495	 * RX_HANDLER_CONSUMED, stopping RX processing for these frames.
496	 */
497	if ((dev->flags & IFF_LOOPBACK) ||
498	    dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN ||
499	    !is_valid_ether_addr(dev->dev_addr) ||
500	    netdev_uses_dsa(dev))
501		return -EINVAL;
502
503	/* No bridging of bridges */
504	if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
505		return -ELOOP;
506
507	/* Device is already being bridged */
508	if (br_port_exists(dev))
509		return -EBUSY;
510
511	/* No bridging devices that dislike that (e.g. wireless) */
512	if (dev->priv_flags & IFF_DONT_BRIDGE)
513		return -EOPNOTSUPP;
514
515	p = new_nbp(br, dev);
516	if (IS_ERR(p))
517		return PTR_ERR(p);
518
519	call_netdevice_notifiers(NETDEV_JOIN, dev);
520
521	err = dev_set_allmulti(dev, 1);
522	if (err)
523		goto put_back;
524
525	err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
526				   SYSFS_BRIDGE_PORT_ATTR);
527	if (err)
 
 
 
 
528		goto err1;
529
530	err = br_sysfs_addif(p);
531	if (err)
532		goto err2;
533
534	err = br_netpoll_enable(p);
 
 
 
535	if (err)
536		goto err3;
537
538	err = netdev_rx_handler_register(dev, br_handle_frame, p);
539	if (err)
540		goto err4;
541
542	dev->priv_flags |= IFF_BRIDGE_PORT;
543
544	err = netdev_master_upper_dev_link(dev, br->dev, NULL, NULL);
545	if (err)
546		goto err5;
547
548	err = nbp_switchdev_mark_set(p);
549	if (err)
550		goto err6;
551
552	dev_disable_lro(dev);
553
554	list_add_rcu(&p->list, &br->port_list);
555
556	nbp_update_port_count(br);
557
558	netdev_update_features(br->dev);
559
560	br_hr = br->dev->needed_headroom;
561	dev_hr = netdev_get_fwd_headroom(dev);
562	if (br_hr < dev_hr)
563		update_headroom(br, dev_hr);
564	else
565		netdev_set_rx_headroom(dev, br_hr);
566
567	if (br_fdb_insert(br, p, dev->dev_addr, 0))
568		netdev_err(dev, "failed insert local address bridge forwarding table\n");
569
570	err = nbp_vlan_init(p);
571	if (err) {
572		netdev_err(dev, "failed to initialize vlan filtering on this port\n");
573		goto err7;
574	}
575
576	spin_lock_bh(&br->lock);
577	changed_addr = br_stp_recalculate_bridge_id(br);
578
579	if (netif_running(dev) && netif_oper_up(dev) &&
580	    (br->dev->flags & IFF_UP))
581		br_stp_enable_port(p);
582	spin_unlock_bh(&br->lock);
583
584	br_ifinfo_notify(RTM_NEWLINK, p);
585
586	if (changed_addr)
587		call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
588
589	dev_set_mtu(br->dev, br_min_mtu(br));
590	br_set_gso_limits(br);
591
592	kobject_uevent(&p->kobj, KOBJ_ADD);
593
594	return 0;
595
596err7:
597	list_del_rcu(&p->list);
598	br_fdb_delete_by_port(br, p, 0, 1);
599	nbp_update_port_count(br);
600err6:
601	netdev_upper_dev_unlink(dev, br->dev);
602err5:
603	dev->priv_flags &= ~IFF_BRIDGE_PORT;
604	netdev_rx_handler_unregister(dev);
605err4:
606	br_netpoll_disable(p);
607err3:
608	sysfs_remove_link(br->ifobj, p->dev->name);
609err2:
 
 
610	kobject_put(&p->kobj);
611	p = NULL; /* kobject_put frees */
612err1:
613	dev_set_allmulti(dev, -1);
614put_back:
615	dev_put(dev);
616	kfree(p);
617	return err;
618}
619
620/* called with RTNL */
621int br_del_if(struct net_bridge *br, struct net_device *dev)
622{
623	struct net_bridge_port *p;
624	bool changed_addr;
625
626	p = br_port_get_rtnl(dev);
627	if (!p || p->br != br)
628		return -EINVAL;
629
630	/* Since more than one interface can be attached to a bridge,
631	 * there still maybe an alternate path for netconsole to use;
632	 * therefore there is no reason for a NETDEV_RELEASE event.
633	 */
634	del_nbp(p);
635
636	dev_set_mtu(br->dev, br_min_mtu(br));
637	br_set_gso_limits(br);
638
639	spin_lock_bh(&br->lock);
640	changed_addr = br_stp_recalculate_bridge_id(br);
641	spin_unlock_bh(&br->lock);
642
643	if (changed_addr)
644		call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
645
646	netdev_update_features(br->dev);
647
648	return 0;
649}
650
651void br_port_flags_change(struct net_bridge_port *p, unsigned long mask)
652{
653	struct net_bridge *br = p->br;
 
 
 
 
 
 
 
 
 
654
655	if (mask & BR_AUTO_MASK)
656		nbp_update_port_count(br);
657}