[mirror_ubuntu-zesty-kernel.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/etherdevice.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 <linux/if_vlan.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)
{
	struct ethtool_cmd ecmd;

	if (!__ethtool_get_settings(dev, &ecmd)) {
		switch (ethtool_cmd_speed(&ecmd)) {
		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 transitions. */
void br_port_carrier_check(struct net_bridge_port *p)
{
	struct net_device *dev = p->dev;
	struct net_bridge *br = p->br;

	if (!(p->flags & BR_ADMIN_COST) &&
	    netif_running(dev) && netif_oper_up(dev))
		p->path_cost = port_cost(dev);

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

	spin_lock_bh(&br->lock);
	if (netif_running(dev) && netif_oper_up(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 nbp_update_port_count(struct net_bridge *br)
{
	struct net_bridge_port *p;
	u32 cnt = 0;

	list_for_each_entry(p, &br->port_list, list) {
		if (br_auto_port(p))
			cnt++;
	}
	br->auto_cnt = cnt;
}

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);

	nbp_vlan_flush(p);
	br_fdb_delete_by_port(br, p, 1);

	list_del_rcu(&p->list);

	nbp_update_port_count(br);

	dev->priv_flags &= ~IFF_BRIDGE_PORT;

	netdev_rx_handler_unregister(dev);

	netdev_upper_dev_unlink(dev, br->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);
}

/* Delete bridge device */
void br_dev_delete(struct net_device *dev, struct list_head *head)
{
	struct net_bridge *br = netdev_priv(dev);
	struct net_bridge_port *p, *n;

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

	br_fdb_delete_by_port(br, NULL, 1);

	br_vlan_flush(br);
	del_timer_sync(&br->gc_timer);

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

/* 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 = BR_LEARNING | BR_FLOOD | BR_PROMISC;
	br_init_port(p);
	p->state = BR_STATE_DISABLED;
	br_stp_port_timer_init(p);
	br_multicast_add_port(p);

	return p;
}

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

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

	if (!dev)
		return -ENOMEM;

	dev_net_set(dev, net);
	dev->rtnl_link_ops = &br_link_ops;

	res = register_netdev(dev);
	if (res)
		free_netdev(dev);
	return res;
}

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
		br_dev_delete(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
 */
netdev_features_t br_features_recompute(struct net_bridge *br,
	netdev_features_t features)
{
	struct net_bridge_port *p;
	netdev_features_t mask;

	if (list_empty(&br->port_list))
		return features;

	mask = features;
	features &= ~NETIF_F_ONE_FOR_ALL;

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

	return features;
}

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

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

	call_netdevice_notifiers(NETDEV_JOIN, dev);

	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 err1;

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

	err = br_netpoll_enable(p);
	if (err)
		goto err3;

	err = netdev_master_upper_dev_link(dev, br->dev);
	if (err)
		goto err4;

	err = netdev_rx_handler_register(dev, br_handle_frame, p);
	if (err)
		goto err5;

	dev->priv_flags |= IFF_BRIDGE_PORT;

	dev_disable_lro(dev);

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

	nbp_update_port_count(br);

	netdev_update_features(br->dev);

	if (br->dev->needed_headroom < dev->needed_headroom)
		br->dev->needed_headroom = dev->needed_headroom;

	if (br_fdb_insert(br, p, dev->dev_addr, 0))
		netdev_err(dev, "failed insert local address bridge forwarding table\n");

	spin_lock_bh(&br->lock);
	changed_addr = br_stp_recalculate_bridge_id(br);

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

	br_ifinfo_notify(RTM_NEWLINK, p);

	if (changed_addr)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);

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

	kobject_uevent(&p->kobj, KOBJ_ADD);

	return 0;

err5:
	netdev_upper_dev_unlink(dev, br->dev);
err4:
	br_netpoll_disable(p);
err3:
	sysfs_remove_link(br->ifobj, p->dev->name);
err2:
	kobject_put(&p->kobj);
	p = NULL; /* kobject_put frees */
err1:
	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;
	bool changed_addr;

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

	/* Since more than one interface can be attached to a bridge,
	 * there still maybe an alternate path for netconsole to use;
	 * therefore there is no reason for a NETDEV_RELEASE event.
	 */
	del_nbp(p);

	spin_lock_bh(&br->lock);
	changed_addr = br_stp_recalculate_bridge_id(br);
	spin_unlock_bh(&br->lock);

	if (changed_addr)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);

	netdev_update_features(br->dev);

	return 0;
}

void br_port_flags_change(struct net_bridge_port *p, unsigned long mask)
{
	struct net_bridge *br = p->br;

	if (mask & BR_AUTO_MASK)
		nbp_update_port_count(br);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Userspace interface
	3	* Linux ethernet bridge
	4	*
	5	* Authors:
	6	* Lennert Buytenhek <buytenh@gnu.org>
	7	*
1da177e4 LT	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>
77f98598	16	#include <linux/etherdevice.h>
c06ee961	17	#include <linux/netpoll.h>
1da177e4 LT	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>
46f25dff	23	#include <linux/if_ether.h>
5a0e3ad6	24	#include <linux/slab.h>
1da177e4	25	#include <net/sock.h>
407af329	26	#include <linux/if_vlan.h>
1da177e4 LT	27
	28	#include "br_private.h"
	29
	30	/*
	31	* Determine initial path cost based on speed.
	32	* using recommendations from 802.1d standard
	33	*
61a44b9c	34	* Since driver might sleep need to not be holding any locks.
1da177e4	35	*/
4433f420	36	static int port_cost(struct net_device *dev)
1da177e4	37	{
fa3df928	38	struct ethtool_cmd ecmd;
b4a488d1	39
4bc71cb9	40	if (!__ethtool_get_settings(dev, &ecmd)) {
fa3df928 JP	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;
1da177e4 LT	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
4433f420	63
1a81a2e0	64	/* Check for port carrier transitions. */
269def7c	65	void br_port_carrier_check(struct net_bridge_port *p)
4433f420	66	{
269def7c SH	67	struct net_device *dev = p->dev;
269def7c SH	68	struct net_bridge *br = p->br;
6e86b890	69
8f3359bd	70	if (!(p->flags & BR_ADMIN_COST) &&
8f3359bd	71	netif_running(dev) && netif_oper_up(dev))
6e86b890 SH	72	p->path_cost = port_cost(dev);
6e86b890 SH	73
aa7c6e5f	74	if (!netif_running(br->dev))
	75	return;
	76
	77	spin_lock_bh(&br->lock);
576eb625	78	if (netif_running(dev) && netif_oper_up(dev)) {
aa7c6e5f	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);
4433f420	84	}
aa7c6e5f	85	spin_unlock_bh(&br->lock);
4433f420 SH	86	}
4433f420 SH	87
e028e4b8 VY	88	static void nbp_update_port_count(struct net_bridge *br)
	89	{
	90	struct net_bridge_port *p;
	91	u32 cnt = 0;
	92
	93	list_for_each_entry(p, &br->port_list, list) {
	94	if (br_auto_port(p))
	95	cnt++;
	96	}
	97	br->auto_cnt = cnt;
	98	}
	99
bab1deea SH	100	static void release_nbp(struct kobject *kobj)
	101	{
	102	struct net_bridge_port *p
	103	= container_of(kobj, struct net_bridge_port, kobj);
	104	kfree(p);
	105	}
	106
	107	static struct kobj_type brport_ktype = {
	108	#ifdef CONFIG_SYSFS
	109	.sysfs_ops = &brport_sysfs_ops,
	110	#endif
	111	.release = release_nbp,
	112	};
	113
1da177e4 LT	114	static void destroy_nbp(struct net_bridge_port *p)
	115	{
	116	struct net_device *dev = p->dev;
	117
1da177e4 LT	118	p->br = NULL;
	119	p->dev = NULL;
	120	dev_put(dev);
	121
bab1deea	122	kobject_put(&p->kobj);
1da177e4 LT	123	}
	124
	125	static void destroy_nbp_rcu(struct rcu_head *head)
	126	{
	127	struct net_bridge_port *p =
	128	container_of(head, struct net_bridge_port, rcu);
	129	destroy_nbp(p);
	130	}
	131
3f4cfc2d SH	132	/* Delete port(interface) from bridge is done in two steps.
	133	* via RCU. First step, marks device as down. That deletes
	134	* all the timers and stops new packets from flowing through.
	135	*
	136	* Final cleanup doesn't occur until after all CPU's finished
	137	* processing packets.
	138	*
	139	* Protected from multiple admin operations by RTNL mutex
	140	*/
1da177e4 LT	141	static void del_nbp(struct net_bridge_port *p)
	142	{
	143	struct net_bridge *br = p->br;
	144	struct net_device *dev = p->dev;
	145
b3bcb72e	146	sysfs_remove_link(br->ifobj, p->dev->name);
bab1deea	147
1da177e4 LT	148	dev_set_promiscuity(dev, -1);
	149
	150	spin_lock_bh(&br->lock);
	151	br_stp_disable_port(p);
	152	spin_unlock_bh(&br->lock);
	153
b86c4503 SH	154	br_ifinfo_notify(RTM_DELLINK, p);
b86c4503 SH	155
243a2e63	156	nbp_vlan_flush(p);
1a620698	157	br_fdb_delete_by_port(br, p, 1);
1da177e4 LT	158
	159	list_del_rcu(&p->list);
	160
e028e4b8 VY	161	nbp_update_port_count(br);
e028e4b8 VY	162
f350a0a8 JP	163	dev->priv_flags &= ~IFF_BRIDGE_PORT;
f350a0a8 JP	164
ab95bfe0	165	netdev_rx_handler_unregister(dev);
b3f1be4b	166
74fdd93f	167	netdev_upper_dev_unlink(dev, br->dev);
afc6151a	168
3fe2d7c7 HX	169	br_multicast_del_port(p);
3fe2d7c7 HX	170
125a12cc	171	kobject_uevent(&p->kobj, KOBJ_REMOVE);
bab1deea SH	172	kobject_del(&p->kobj);
bab1deea SH	173
91d2c34a HX	174	br_netpoll_disable(p);
91d2c34a HX	175
1da177e4 LT	176	call_rcu(&p->rcu, destroy_nbp_rcu);
	177	}
	178
1ce5cce8	179	/* Delete bridge device */
1ce5cce8	180	void br_dev_delete(struct net_device dev, struct list_head head)
1da177e4	181	{
1ce5cce8	182	struct net_bridge *br = netdev_priv(dev);
1da177e4 LT	183	struct net_bridge_port p, n;
	184
	185	list_for_each_entry_safe(p, n, &br->port_list, list) {
1da177e4 LT	186	del_nbp(p);
	187	}
	188
f8730420 DT	189	br_fdb_delete_by_port(br, NULL, 1);
f8730420 DT	190
b4e09b29	191	br_vlan_flush(br);
1da177e4 LT	192	del_timer_sync(&br->gc_timer);
	193
	194	br_sysfs_delbr(br->dev);
8c56ba05	195	unregister_netdevice_queue(br->dev, head);
1da177e4 LT	196	}
1da177e4 LT	197
1da177e4 LT	198	/* find an available port number */
	199	static int find_portno(struct net_bridge *br)
	200	{
	201	int index;
	202	struct net_bridge_port *p;
	203	unsigned long *inuse;
	204
3b781fa1	205	inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
1da177e4 LT	206	GFP_KERNEL);
	207	if (!inuse)
	208	return -ENOMEM;
	209
1da177e4 LT	210	set_bit(0, inuse); /* zero is reserved */
	211	list_for_each_entry(p, &br->port_list, list) {
	212	set_bit(p->port_no, inuse);
	213	}
	214	index = find_first_zero_bit(inuse, BR_MAX_PORTS);
	215	kfree(inuse);
	216
	217	return (index >= BR_MAX_PORTS) ? -EXFULL : index;
	218	}
	219
4433f420	220	/* called with RTNL but without bridge lock */
9d6f229f	221	static struct net_bridge_port new_nbp(struct net_bridge br,
4433f420	222	struct net_device *dev)
1da177e4 LT	223	{
	224	int index;
	225	struct net_bridge_port *p;
9d6f229f	226
1da177e4 LT	227	index = find_portno(br);
	228	if (index < 0)
	229	return ERR_PTR(index);
	230
cee48541	231	p = kzalloc(sizeof(*p), GFP_KERNEL);
1da177e4 LT	232	if (p == NULL)
	233	return ERR_PTR(-ENOMEM);
	234
1da177e4 LT	235	p->br = br;
	236	dev_hold(dev);
	237	p->dev = dev;
4433f420	238	p->path_cost = port_cost(dev);
9d6f229f	239	p->priority = 0x8000 >> BR_PORT_BITS;
1da177e4	240	p->port_no = index;
f3a6ddf1	241	p->flags = BR_LEARNING \| BR_FLOOD \| BR_PROMISC;
1da177e4 LT	242	br_init_port(p);
1da177e4 LT	243	p->state = BR_STATE_DISABLED;
d32439c0	244	br_stp_port_timer_init(p);
3fe2d7c7	245	br_multicast_add_port(p);
1da177e4 LT	246
	247	return p;
	248	}
	249
4aa678ba	250	int br_add_bridge(struct net net, const char name)
1da177e4 LT	251	{
1da177e4 LT	252	struct net_device *dev;
11f3a6bd	253	int res;
1da177e4	254
bb900b27	255	dev = alloc_netdev(sizeof(struct net_bridge), name,
	256	br_dev_setup);
	257
9d6f229f	258	if (!dev)
1da177e4 LT	259	return -ENOMEM;
1da177e4 LT	260
bb900b27	261	dev_net_set(dev, net);
149ddd83	262	dev->rtnl_link_ops = &br_link_ops;
e340a90e	263
11f3a6bd ED	264	res = register_netdev(dev);
	265	if (res)
	266	free_netdev(dev);
	267	return res;
1da177e4 LT	268	}
1da177e4 LT	269
4aa678ba	270	int br_del_bridge(struct net net, const char name)
1da177e4 LT	271	{
	272	struct net_device *dev;
	273	int ret = 0;
	274
	275	rtnl_lock();
4aa678ba	276	dev = __dev_get_by_name(net, name);
9d6f229f	277	if (dev == NULL)
1da177e4 LT	278	ret = -ENXIO; /* Could not find device */
	279
	280	else if (!(dev->priv_flags & IFF_EBRIDGE)) {
	281	/* Attempt to delete non bridge device! */
	282	ret = -EPERM;
	283	}
	284
	285	else if (dev->flags & IFF_UP) {
	286	/* Not shutdown yet. */
	287	ret = -EBUSY;
9d6f229f	288	}
1da177e4	289
9d6f229f	290	else
1ce5cce8	291	br_dev_delete(dev, NULL);
1da177e4 LT	292
	293	rtnl_unlock();
	294	return ret;
	295	}
	296
46f25dff	297	/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
1da177e4 LT	298	int br_min_mtu(const struct net_bridge *br)
	299	{
	300	const struct net_bridge_port *p;
	301	int mtu = 0;
	302
	303	ASSERT_RTNL();
	304
	305	if (list_empty(&br->port_list))
46f25dff	306	mtu = ETH_DATA_LEN;
1da177e4 LT	307	else {
	308	list_for_each_entry(p, &br->port_list, list) {
	309	if (!mtu \|\| p->dev->mtu < mtu)
	310	mtu = p->dev->mtu;
	311	}
	312	}
	313	return mtu;
	314	}
	315
81d35307 SH	316	/*
	317	* Recomputes features using slave's features
	318	*/
c8f44aff MM	319	netdev_features_t br_features_recompute(struct net_bridge *br,
c8f44aff MM	320	netdev_features_t features)
81d35307 SH	321	{
81d35307 SH	322	struct net_bridge_port *p;
c8f44aff	323	netdev_features_t mask;
81d35307	324
b63365a2	325	if (list_empty(&br->port_list))
c4d27ef9	326	return features;
b63365a2	327
c4d27ef9	328	mask = features;
b63365a2	329	features &= ~NETIF_F_ONE_FOR_ALL;
81d35307 SH	330
81d35307 SH	331	list_for_each_entry(p, &br->port_list, list) {
b63365a2 HX	332	features = netdev_increment_features(features,
b63365a2 HX	333	p->dev->features, mask);
81d35307 SH	334	}
81d35307 SH	335
c4d27ef9	336	return features;
81d35307 SH	337	}
81d35307 SH	338
1da177e4 LT	339	/* called with RTNL */
	340	int br_add_if(struct net_bridge br, struct net_device dev)
	341	{
	342	struct net_bridge_port *p;
	343	int err = 0;
edf947f1	344	bool changed_addr;
1da177e4	345
1056bd51 SH	346	/* Don't allow bridging non-ethernet like devices */
1056bd51 SH	347	if ((dev->flags & IFF_LOOPBACK) \|\|
77f98598	348	dev->type != ARPHRD_ETHER \|\| dev->addr_len != ETH_ALEN \|\|
77f98598	349	!is_valid_ether_addr(dev->dev_addr))
1da177e4 LT	350	return -EINVAL;
1da177e4 LT	351
1056bd51	352	/* No bridging of bridges */
00829823	353	if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
1da177e4 LT	354	return -ELOOP;
1da177e4 LT	355
1056bd51	356	/* Device is already being bridged */
f350a0a8	357	if (br_port_exists(dev))
1da177e4 LT	358	return -EBUSY;
1da177e4 LT	359
ad4bb6f8 JB	360	/* No bridging devices that dislike that (e.g. wireless) */
	361	if (dev->priv_flags & IFF_DONT_BRIDGE)
	362	return -EOPNOTSUPP;
	363
bab1deea SH	364	p = new_nbp(br, dev);
bab1deea SH	365	if (IS_ERR(p))
1da177e4 LT	366	return PTR_ERR(p);
1da177e4 LT	367
bb8ed630 AW	368	call_netdevice_notifiers(NETDEV_JOIN, dev);
bb8ed630 AW	369
bc3f9076 WC	370	err = dev_set_promiscuity(dev, 1);
	371	if (err)
	372	goto put_back;
	373
e32cc736 GKH	374	err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
e32cc736 GKH	375	SYSFS_BRIDGE_PORT_ATTR);
bab1deea SH	376	if (err)
bab1deea SH	377	goto err1;
1da177e4	378
bab1deea SH	379	err = br_sysfs_addif(p);
	380	if (err)
	381	goto err2;
1da177e4	382
a8779ec1	383	err = br_netpoll_enable(p);
93d8bf9f	384	if (err)
91d2c34a HX	385	goto err3;
91d2c34a HX	386
74fdd93f	387	err = netdev_master_upper_dev_link(dev, br->dev);
ab95bfe0	388	if (err)
9b1536c4	389	goto err4;
f350a0a8	390
afc6151a JP	391	err = netdev_rx_handler_register(dev, br_handle_frame, p);
afc6151a JP	392	if (err)
9b1536c4	393	goto err5;
afc6151a	394
f350a0a8	395	dev->priv_flags \|= IFF_BRIDGE_PORT;
ab95bfe0	396
0187bdfb	397	dev_disable_lro(dev);
bab1deea SH	398
	399	list_add_rcu(&p->list, &br->port_list);
	400
e028e4b8 VY	401	nbp_update_port_count(br);
e028e4b8 VY	402
c4d27ef9 MM	403	netdev_update_features(br->dev);
c4d27ef9 MM	404
fd094808 FF	405	if (br->dev->needed_headroom < dev->needed_headroom)
	406	br->dev->needed_headroom = dev->needed_headroom;
	407
a4b816d8 TM	408	if (br_fdb_insert(br, p, dev->dev_addr, 0))
	409	netdev_err(dev, "failed insert local address bridge forwarding table\n");
	410
bab1deea	411	spin_lock_bh(&br->lock);
edf947f1	412	changed_addr = br_stp_recalculate_bridge_id(br);
de79059e	413
576eb625	414	if (netif_running(dev) && netif_oper_up(dev) &&
de79059e AS	415	(br->dev->flags & IFF_UP))
de79059e AS	416	br_stp_enable_port(p);
bab1deea SH	417	spin_unlock_bh(&br->lock);
bab1deea SH	418
b86c4503 SH	419	br_ifinfo_notify(RTM_NEWLINK, p);
b86c4503 SH	420
edf947f1	421	if (changed_addr)
56139fc5	422	call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
edf947f1	423
bab1deea	424	dev_set_mtu(br->dev, br_min_mtu(br));
269def7c	425
bab1deea	426	kobject_uevent(&p->kobj, KOBJ_ADD);
1da177e4	427
bab1deea	428	return 0;
afc6151a	429
9b1536c4	430	err5:
74fdd93f	431	netdev_upper_dev_unlink(dev, br->dev);
9b1536c4 G	432	err4:
9b1536c4 G	433	br_netpoll_disable(p);
91d2c34a HX	434	err3:
91d2c34a HX	435	sysfs_remove_link(br->ifobj, p->dev->name);
bab1deea	436	err2:
c587aea9	437	kobject_put(&p->kobj);
30df94f8	438	p = NULL; /* kobject_put frees */
77f98598	439	err1:
bc3f9076	440	dev_set_promiscuity(dev, -1);
43af8532 VL	441	put_back:
43af8532 VL	442	dev_put(dev);
bc3f9076	443	kfree(p);
1da177e4 LT	444	return err;
	445	}
	446
	447	/* called with RTNL */
	448	int br_del_if(struct net_bridge br, struct net_device dev)
	449	{
f350a0a8	450	struct net_bridge_port *p;
9be6dd65	451	bool changed_addr;
f350a0a8	452
ec1e5610	453	p = br_port_get_rtnl(dev);
b5ed54e9	454	if (!p \|\| p->br != br)
1da177e4 LT	455	return -EINVAL;
1da177e4 LT	456
d30362c0 AW	457	/* Since more than one interface can be attached to a bridge,
	458	* there still maybe an alternate path for netconsole to use;
	459	* therefore there is no reason for a NETDEV_RELEASE event.
	460	*/
1da177e4 LT	461	del_nbp(p);
	462
	463	spin_lock_bh(&br->lock);
9be6dd65	464	changed_addr = br_stp_recalculate_bridge_id(br);
1da177e4 LT	465	spin_unlock_bh(&br->lock);
1da177e4 LT	466
9be6dd65 AW	467	if (changed_addr)
	468	call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
	469
c4d27ef9 MM	470	netdev_update_features(br->dev);
c4d27ef9 MM	471
1da177e4 LT	472	return 0;
1da177e4 LT	473	}
e028e4b8 VY	474
	475	void br_port_flags_change(struct net_bridge_port *p, unsigned long mask)
	476	{
	477	struct net_bridge *br = p->br;
	478
	479	if (mask & BR_AUTO_MASK)
	480	nbp_update_port_count(br);
	481	}