[net-next-2.6.git] / net / bridge / br_if.c

/*
 *	Userspace interface
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/netpoll.h>
#include <linux/ethtool.h>
#include <linux/if_arp.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/rtnetlink.h>
#include <linux/if_ether.h>
#include <linux/slab.h>
#include <net/sock.h>

#include "br_private.h"

/*
 * Determine initial path cost based on speed.
 * using recommendations from 802.1d standard
 *
 * Since driver might sleep need to not be holding any locks.
 */
static int port_cost(struct net_device *dev)
{
	if (dev->ethtool_ops && dev->ethtool_ops->get_settings) {
		struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET, };

		if (!dev->ethtool_ops->get_settings(dev, &ecmd)) {
			switch(ecmd.speed) {
			case SPEED_10000:
				return 2;
			case SPEED_1000:
				return 4;
			case SPEED_100:
				return 19;
			case SPEED_10:
				return 100;
			}
		}
	}

	/* Old silly heuristics based on name */
	if (!strncmp(dev->name, "lec", 3))
		return 7;

	if (!strncmp(dev->name, "plip", 4))
		return 2500;

	return 100;	/* assume old 10Mbps */
}


/* Check for port carrier transistions. */
void br_port_carrier_check(struct net_bridge_port *p)
{
	struct net_device *dev = p->dev;
	struct net_bridge *br = p->br;

	if (netif_running(dev) && netif_carrier_ok(dev))
		p->path_cost = port_cost(dev);

	if (!netif_running(br->dev))
		return;

	spin_lock_bh(&br->lock);
	if (netif_running(dev) && netif_carrier_ok(dev)) {
		if (p->state == BR_STATE_DISABLED)
			br_stp_enable_port(p);
	} else {
		if (p->state != BR_STATE_DISABLED)
			br_stp_disable_port(p);
	}
	spin_unlock_bh(&br->lock);
}

static void release_nbp(struct kobject *kobj)
{
	struct net_bridge_port *p
		= container_of(kobj, struct net_bridge_port, kobj);
	kfree(p);
}

static struct kobj_type brport_ktype = {
#ifdef CONFIG_SYSFS
	.sysfs_ops = &brport_sysfs_ops,
#endif
	.release = release_nbp,
};

static void destroy_nbp(struct net_bridge_port *p)
{
	struct net_device *dev = p->dev;

	p->br = NULL;
	p->dev = NULL;
	dev_put(dev);

	kobject_put(&p->kobj);
}

static void destroy_nbp_rcu(struct rcu_head *head)
{
	struct net_bridge_port *p =
			container_of(head, struct net_bridge_port, rcu);
	destroy_nbp(p);
}

/* Delete port(interface) from bridge is done in two steps.
 * via RCU. First step, marks device as down. That deletes
 * all the timers and stops new packets from flowing through.
 *
 * Final cleanup doesn't occur until after all CPU's finished
 * processing packets.
 *
 * Protected from multiple admin operations by RTNL mutex
 */
static void del_nbp(struct net_bridge_port *p)
{
	struct net_bridge *br = p->br;
	struct net_device *dev = p->dev;

	sysfs_remove_link(br->ifobj, p->dev->name);

	dev_set_promiscuity(dev, -1);

	spin_lock_bh(&br->lock);
	br_stp_disable_port(p);
	spin_unlock_bh(&br->lock);

	br_ifinfo_notify(RTM_DELLINK, p);

	br_fdb_delete_by_port(br, p, 1);

	list_del_rcu(&p->list);

	dev->priv_flags &= ~IFF_BRIDGE_PORT;

	netdev_rx_handler_unregister(dev);

	br_multicast_del_port(p);

	kobject_uevent(&p->kobj, KOBJ_REMOVE);
	kobject_del(&p->kobj);

	br_netpoll_disable(p);

	call_rcu(&p->rcu, destroy_nbp_rcu);
}

/* called with RTNL */
static void del_br(struct net_bridge *br, struct list_head *head)
{
	struct net_bridge_port *p, *n;

	list_for_each_entry_safe(p, n, &br->port_list, list) {
		del_nbp(p);
	}

	del_timer_sync(&br->gc_timer);

	br_sysfs_delbr(br->dev);
	unregister_netdevice_queue(br->dev, head);
}

static struct net_device *new_bridge_dev(struct net *net, const char *name)
{
	struct net_bridge *br;
	struct net_device *dev;

	dev = alloc_netdev(sizeof(struct net_bridge), name,
			   br_dev_setup);

	if (!dev)
		return NULL;
	dev_net_set(dev, net);

	br = netdev_priv(dev);
	br->dev = dev;

	br->stats = alloc_percpu(struct br_cpu_netstats);
	if (!br->stats) {
		free_netdev(dev);
		return NULL;
	}

	spin_lock_init(&br->lock);
	INIT_LIST_HEAD(&br->port_list);
	spin_lock_init(&br->hash_lock);

	br->bridge_id.prio[0] = 0x80;
	br->bridge_id.prio[1] = 0x00;

	memcpy(br->group_addr, br_group_address, ETH_ALEN);

	br->feature_mask = dev->features;
	br->stp_enabled = BR_NO_STP;
	br->designated_root = br->bridge_id;
	br->root_path_cost = 0;
	br->root_port = 0;
	br->bridge_max_age = br->max_age = 20 * HZ;
	br->bridge_hello_time = br->hello_time = 2 * HZ;
	br->bridge_forward_delay = br->forward_delay = 15 * HZ;
	br->topology_change = 0;
	br->topology_change_detected = 0;
	br->ageing_time = 300 * HZ;

	br_netfilter_rtable_init(br);

	br_stp_timer_init(br);
	br_multicast_init(br);

	return dev;
}

/* find an available port number */
static int find_portno(struct net_bridge *br)
{
	int index;
	struct net_bridge_port *p;
	unsigned long *inuse;

	inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
			GFP_KERNEL);
	if (!inuse)
		return -ENOMEM;

	set_bit(0, inuse);	/* zero is reserved */
	list_for_each_entry(p, &br->port_list, list) {
		set_bit(p->port_no, inuse);
	}
	index = find_first_zero_bit(inuse, BR_MAX_PORTS);
	kfree(inuse);

	return (index >= BR_MAX_PORTS) ? -EXFULL : index;
}

/* called with RTNL but without bridge lock */
static struct net_bridge_port *new_nbp(struct net_bridge *br,
				       struct net_device *dev)
{
	int index;
	struct net_bridge_port *p;

	index = find_portno(br);
	if (index < 0)
		return ERR_PTR(index);

	p = kzalloc(sizeof(*p), GFP_KERNEL);
	if (p == NULL)
		return ERR_PTR(-ENOMEM);

	p->br = br;
	dev_hold(dev);
	p->dev = dev;
	p->path_cost = port_cost(dev);
	p->priority = 0x8000 >> BR_PORT_BITS;
	p->port_no = index;
	p->flags = 0;
	br_init_port(p);
	p->state = BR_STATE_DISABLED;
	br_stp_port_timer_init(p);
	br_multicast_add_port(p);

	return p;
}

static struct device_type br_type = {
	.name	= "bridge",
};

int br_add_bridge(struct net *net, const char *name)
{
	struct net_device *dev;
	int ret;

	dev = new_bridge_dev(net, name);
	if (!dev)
		return -ENOMEM;

	rtnl_lock();
	if (strchr(dev->name, '%')) {
		ret = dev_alloc_name(dev, dev->name);
		if (ret < 0)
			goto out_free;
	}

	SET_NETDEV_DEVTYPE(dev, &br_type);

	ret = register_netdevice(dev);
	if (ret)
		goto out_free;

	ret = br_sysfs_addbr(dev);
	if (ret)
		unregister_netdevice(dev);
 out:
	rtnl_unlock();
	return ret;

out_free:
	free_netdev(dev);
	goto out;
}

int br_del_bridge(struct net *net, const char *name)
{
	struct net_device *dev;
	int ret = 0;

	rtnl_lock();
	dev = __dev_get_by_name(net, name);
	if (dev == NULL)
		ret =  -ENXIO; 	/* Could not find device */

	else if (!(dev->priv_flags & IFF_EBRIDGE)) {
		/* Attempt to delete non bridge device! */
		ret = -EPERM;
	}

	else if (dev->flags & IFF_UP) {
		/* Not shutdown yet. */
		ret = -EBUSY;
	}

	else
		del_br(netdev_priv(dev), NULL);

	rtnl_unlock();
	return ret;
}

/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
int br_min_mtu(const struct net_bridge *br)
{
	const struct net_bridge_port *p;
	int mtu = 0;

	ASSERT_RTNL();

	if (list_empty(&br->port_list))
		mtu = ETH_DATA_LEN;
	else {
		list_for_each_entry(p, &br->port_list, list) {
			if (!mtu  || p->dev->mtu < mtu)
				mtu = p->dev->mtu;
		}
	}
	return mtu;
}

/*
 * Recomputes features using slave's features
 */
void br_features_recompute(struct net_bridge *br)
{
	struct net_bridge_port *p;
	unsigned long features, mask;

	features = mask = br->feature_mask;
	if (list_empty(&br->port_list))
		goto done;

	features &= ~NETIF_F_ONE_FOR_ALL;

	list_for_each_entry(p, &br->port_list, list) {
		features = netdev_increment_features(features,
						     p->dev->features, mask);
	}

done:
	br->dev->features = netdev_fix_features(features, NULL);
}

/* called with RTNL */
int br_add_if(struct net_bridge *br, struct net_device *dev)
{
	struct net_bridge_port *p;
	int err = 0;

	/* Don't allow bridging non-ethernet like devices */
	if ((dev->flags & IFF_LOOPBACK) ||
	    dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN)
		return -EINVAL;

	/* No bridging of bridges */
	if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
		return -ELOOP;

	/* Device is already being bridged */
	if (br_port_exists(dev))
		return -EBUSY;

	/* No bridging devices that dislike that (e.g. wireless) */
	if (dev->priv_flags & IFF_DONT_BRIDGE)
		return -EOPNOTSUPP;

	p = new_nbp(br, dev);
	if (IS_ERR(p))
		return PTR_ERR(p);

	err = dev_set_promiscuity(dev, 1);
	if (err)
		goto put_back;

	err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
				   SYSFS_BRIDGE_PORT_ATTR);
	if (err)
		goto err0;

	err = br_fdb_insert(br, p, dev->dev_addr);
	if (err)
		goto err1;

	err = br_sysfs_addif(p);
	if (err)
		goto err2;

	if (br_netpoll_info(br) && ((err = br_netpoll_enable(p))))
		goto err3;

	err = netdev_rx_handler_register(dev, br_handle_frame, p);
	if (err)
		goto err3;

	dev->priv_flags |= IFF_BRIDGE_PORT;

	dev_disable_lro(dev);

	list_add_rcu(&p->list, &br->port_list);

	spin_lock_bh(&br->lock);
	br_stp_recalculate_bridge_id(br);
	br_features_recompute(br);

	if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) &&
	    (br->dev->flags & IFF_UP))
		br_stp_enable_port(p);
	spin_unlock_bh(&br->lock);

	br_ifinfo_notify(RTM_NEWLINK, p);

	dev_set_mtu(br->dev, br_min_mtu(br));

	kobject_uevent(&p->kobj, KOBJ_ADD);

	return 0;
err3:
	sysfs_remove_link(br->ifobj, p->dev->name);
err2:
	br_fdb_delete_by_port(br, p, 1);
err1:
	kobject_put(&p->kobj);
	p = NULL; /* kobject_put frees */
err0:
	dev_set_promiscuity(dev, -1);
put_back:
	dev_put(dev);
	kfree(p);
	return err;
}

/* called with RTNL */
int br_del_if(struct net_bridge *br, struct net_device *dev)
{
	struct net_bridge_port *p;

	p = br_port_get_rtnl(dev);
	if (!p || p->br != br)
		return -EINVAL;

	del_nbp(p);

	spin_lock_bh(&br->lock);
	br_stp_recalculate_bridge_id(br);
	br_features_recompute(br);
	spin_unlock_bh(&br->lock);

	return 0;
}

void __net_exit br_net_exit(struct net *net)
{
	struct net_device *dev;
	LIST_HEAD(list);

	rtnl_lock();
	for_each_netdev(net, dev)
		if (dev->priv_flags & IFF_EBRIDGE)
			del_br(netdev_priv(dev), &list);

	unregister_netdevice_many(&list);
	rtnl_unlock();

}
Commit	Line	Data
	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	*/
	34	static 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_ops->get_settings(dev, &ecmd)) {
	40	switch(ecmd.speed) {
	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. */
	65	void 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
	87	static 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
	94	static struct kobj_type brport_ktype = {
	95	#ifdef CONFIG_SYSFS
	96	.sysfs_ops = &brport_sysfs_ops,
	97	#endif
	98	.release = release_nbp,
	99	};
	100
	101	static 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
	112	static 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	*/
	128	static 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
	151	br_multicast_del_port(p);
	152
	153	kobject_uevent(&p->kobj, KOBJ_REMOVE);
	154	kobject_del(&p->kobj);
	155
	156	br_netpoll_disable(p);
	157
	158	call_rcu(&p->rcu, destroy_nbp_rcu);
	159	}
	160
	161	/* called with RTNL */
	162	static void del_br(struct net_bridge br, struct list_head head)
	163	{
	164	struct net_bridge_port p, n;
	165
	166	list_for_each_entry_safe(p, n, &br->port_list, list) {
	167	del_nbp(p);
	168	}
	169
	170	del_timer_sync(&br->gc_timer);
	171
	172	br_sysfs_delbr(br->dev);
	173	unregister_netdevice_queue(br->dev, head);
	174	}
	175
	176	static struct net_device new_bridge_dev(struct net net, const char *name)
	177	{
	178	struct net_bridge *br;
	179	struct net_device *dev;
	180
	181	dev = alloc_netdev(sizeof(struct net_bridge), name,
	182	br_dev_setup);
	183
	184	if (!dev)
	185	return NULL;
	186	dev_net_set(dev, net);
	187
	188	br = netdev_priv(dev);
	189	br->dev = dev;
	190
	191	br->stats = alloc_percpu(struct br_cpu_netstats);
	192	if (!br->stats) {
	193	free_netdev(dev);
	194	return NULL;
	195	}
	196
	197	spin_lock_init(&br->lock);
	198	INIT_LIST_HEAD(&br->port_list);
	199	spin_lock_init(&br->hash_lock);
	200
	201	br->bridge_id.prio[0] = 0x80;
	202	br->bridge_id.prio[1] = 0x00;
	203
	204	memcpy(br->group_addr, br_group_address, ETH_ALEN);
	205
	206	br->feature_mask = dev->features;
	207	br->stp_enabled = BR_NO_STP;
	208	br->designated_root = br->bridge_id;
	209	br->root_path_cost = 0;
	210	br->root_port = 0;
	211	br->bridge_max_age = br->max_age = 20 * HZ;
	212	br->bridge_hello_time = br->hello_time = 2 * HZ;
	213	br->bridge_forward_delay = br->forward_delay = 15 * HZ;
	214	br->topology_change = 0;
	215	br->topology_change_detected = 0;
	216	br->ageing_time = 300 * HZ;
	217
	218	br_netfilter_rtable_init(br);
	219
	220	br_stp_timer_init(br);
	221	br_multicast_init(br);
	222
	223	return dev;
	224	}
	225
	226	/* find an available port number */
	227	static int find_portno(struct net_bridge *br)
	228	{
	229	int index;
	230	struct net_bridge_port *p;
	231	unsigned long *inuse;
	232
	233	inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
	234	GFP_KERNEL);
	235	if (!inuse)
	236	return -ENOMEM;
	237
	238	set_bit(0, inuse); /* zero is reserved */
	239	list_for_each_entry(p, &br->port_list, list) {
	240	set_bit(p->port_no, inuse);
	241	}
	242	index = find_first_zero_bit(inuse, BR_MAX_PORTS);
	243	kfree(inuse);
	244
	245	return (index >= BR_MAX_PORTS) ? -EXFULL : index;
	246	}
	247
	248	/* called with RTNL but without bridge lock */
	249	static struct net_bridge_port new_nbp(struct net_bridge br,
	250	struct net_device *dev)
	251	{
	252	int index;
	253	struct net_bridge_port *p;
	254
	255	index = find_portno(br);
	256	if (index < 0)
	257	return ERR_PTR(index);
	258
	259	p = kzalloc(sizeof(*p), GFP_KERNEL);
	260	if (p == NULL)
	261	return ERR_PTR(-ENOMEM);
	262
	263	p->br = br;
	264	dev_hold(dev);
	265	p->dev = dev;
	266	p->path_cost = port_cost(dev);
	267	p->priority = 0x8000 >> BR_PORT_BITS;
	268	p->port_no = index;
	269	p->flags = 0;
	270	br_init_port(p);
	271	p->state = BR_STATE_DISABLED;
	272	br_stp_port_timer_init(p);
	273	br_multicast_add_port(p);
	274
	275	return p;
	276	}
	277
	278	static struct device_type br_type = {
	279	.name = "bridge",
	280	};
	281
	282	int br_add_bridge(struct net net, const char name)
	283	{
	284	struct net_device *dev;
	285	int ret;
	286
	287	dev = new_bridge_dev(net, name);
	288	if (!dev)
	289	return -ENOMEM;
	290
	291	rtnl_lock();
	292	if (strchr(dev->name, '%')) {
	293	ret = dev_alloc_name(dev, dev->name);
	294	if (ret < 0)
	295	goto out_free;
	296	}
	297
	298	SET_NETDEV_DEVTYPE(dev, &br_type);
	299
	300	ret = register_netdevice(dev);
	301	if (ret)
	302	goto out_free;
	303
	304	ret = br_sysfs_addbr(dev);
	305	if (ret)
	306	unregister_netdevice(dev);
	307	out:
	308	rtnl_unlock();
	309	return ret;
	310
	311	out_free:
	312	free_netdev(dev);
	313	goto out;
	314	}
	315
	316	int br_del_bridge(struct net net, const char name)
	317	{
	318	struct net_device *dev;
	319	int ret = 0;
	320
	321	rtnl_lock();
	322	dev = __dev_get_by_name(net, name);
	323	if (dev == NULL)
	324	ret = -ENXIO; /* Could not find device */
	325
	326	else if (!(dev->priv_flags & IFF_EBRIDGE)) {
	327	/* Attempt to delete non bridge device! */
	328	ret = -EPERM;
	329	}
	330
	331	else if (dev->flags & IFF_UP) {
	332	/* Not shutdown yet. */
	333	ret = -EBUSY;
	334	}
	335
	336	else
	337	del_br(netdev_priv(dev), NULL);
	338
	339	rtnl_unlock();
	340	return ret;
	341	}
	342
	343	/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
	344	int br_min_mtu(const struct net_bridge *br)
	345	{
	346	const struct net_bridge_port *p;
	347	int mtu = 0;
	348
	349	ASSERT_RTNL();
	350
	351	if (list_empty(&br->port_list))
	352	mtu = ETH_DATA_LEN;
	353	else {
	354	list_for_each_entry(p, &br->port_list, list) {
	355	if (!mtu \|\| p->dev->mtu < mtu)
	356	mtu = p->dev->mtu;
	357	}
	358	}
	359	return mtu;
	360	}
	361
	362	/*
	363	* Recomputes features using slave's features
	364	*/
	365	void br_features_recompute(struct net_bridge *br)
	366	{
	367	struct net_bridge_port *p;
	368	unsigned long features, mask;
	369
	370	features = mask = br->feature_mask;
	371	if (list_empty(&br->port_list))
	372	goto done;
	373
	374	features &= ~NETIF_F_ONE_FOR_ALL;
	375
	376	list_for_each_entry(p, &br->port_list, list) {
	377	features = netdev_increment_features(features,
	378	p->dev->features, mask);
	379	}
	380
	381	done:
	382	br->dev->features = netdev_fix_features(features, NULL);
	383	}
	384
	385	/* called with RTNL */
	386	int br_add_if(struct net_bridge br, struct net_device dev)
	387	{
	388	struct net_bridge_port *p;
	389	int err = 0;
	390
	391	/* Don't allow bridging non-ethernet like devices */
	392	if ((dev->flags & IFF_LOOPBACK) \|\|
	393	dev->type != ARPHRD_ETHER \|\| dev->addr_len != ETH_ALEN)
	394	return -EINVAL;
	395
	396	/* No bridging of bridges */
	397	if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
	398	return -ELOOP;
	399
	400	/* Device is already being bridged */
	401	if (br_port_exists(dev))
	402	return -EBUSY;
	403
	404	/* No bridging devices that dislike that (e.g. wireless) */
	405	if (dev->priv_flags & IFF_DONT_BRIDGE)
	406	return -EOPNOTSUPP;
	407
	408	p = new_nbp(br, dev);
	409	if (IS_ERR(p))
	410	return PTR_ERR(p);
	411
	412	err = dev_set_promiscuity(dev, 1);
	413	if (err)
	414	goto put_back;
	415
	416	err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
	417	SYSFS_BRIDGE_PORT_ATTR);
	418	if (err)
	419	goto err0;
	420
	421	err = br_fdb_insert(br, p, dev->dev_addr);
	422	if (err)
	423	goto err1;
	424
	425	err = br_sysfs_addif(p);
	426	if (err)
	427	goto err2;
	428
	429	if (br_netpoll_info(br) && ((err = br_netpoll_enable(p))))
	430	goto err3;
	431
	432	err = netdev_rx_handler_register(dev, br_handle_frame, p);
	433	if (err)
	434	goto err3;
	435
	436	dev->priv_flags \|= IFF_BRIDGE_PORT;
	437
	438	dev_disable_lro(dev);
	439
	440	list_add_rcu(&p->list, &br->port_list);
	441
	442	spin_lock_bh(&br->lock);
	443	br_stp_recalculate_bridge_id(br);
	444	br_features_recompute(br);
	445
	446	if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) &&
	447	(br->dev->flags & IFF_UP))
	448	br_stp_enable_port(p);
	449	spin_unlock_bh(&br->lock);
	450
	451	br_ifinfo_notify(RTM_NEWLINK, p);
	452
	453	dev_set_mtu(br->dev, br_min_mtu(br));
	454
	455	kobject_uevent(&p->kobj, KOBJ_ADD);
	456
	457	return 0;
	458	err3:
	459	sysfs_remove_link(br->ifobj, p->dev->name);
	460	err2:
	461	br_fdb_delete_by_port(br, p, 1);
	462	err1:
	463	kobject_put(&p->kobj);
	464	p = NULL; /* kobject_put frees */
	465	err0:
	466	dev_set_promiscuity(dev, -1);
	467	put_back:
	468	dev_put(dev);
	469	kfree(p);
	470	return err;
	471	}
	472
	473	/* called with RTNL */
	474	int br_del_if(struct net_bridge br, struct net_device dev)
	475	{
	476	struct net_bridge_port *p;
	477
	478	p = br_port_get_rtnl(dev);
	479	if (!p \|\| p->br != br)
	480	return -EINVAL;
	481
	482	del_nbp(p);
	483
	484	spin_lock_bh(&br->lock);
	485	br_stp_recalculate_bridge_id(br);
	486	br_features_recompute(br);
	487	spin_unlock_bh(&br->lock);
	488
	489	return 0;
	490	}
	491
	492	void __net_exit br_net_exit(struct net *net)
	493	{
	494	struct net_device *dev;
	495	LIST_HEAD(list);
	496
	497	rtnl_lock();
	498	for_each_netdev(net, dev)
	499	if (dev->priv_flags & IFF_EBRIDGE)
	500	del_br(netdev_priv(dev), &list);
	501
	502	unregister_netdevice_many(&list);
	503	rtnl_unlock();
	504
	505	}