[deliverable/linux.git] / net / bridge / br_if.c

/*
 *	Userspace interface
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 *
 *	$Id: br_if.c,v 1.7 2001/12/24 00:59:55 davem Exp $
 *
 *	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/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 <net/sock.h>

#include "br_private.h"

/*
 * Determine initial path cost based on speed.
 * using recommendations from 802.1d standard
 *
 * Need to simulate user ioctl because not all device's that support
 * ethtool, use ethtool_ops.  Also, since driver might sleep need to
 * not be holding any locks.
 */
static int port_cost(struct net_device *dev)
{
	struct ethtool_cmd ecmd = { ETHTOOL_GSET };
	struct ifreq ifr;
	mm_segment_t old_fs;
	int err;

	strncpy(ifr.ifr_name, dev->name, IFNAMSIZ);
	ifr.ifr_data = (void __user *) &ecmd;

	old_fs = get_fs();
	set_fs(KERNEL_DS);
	err = dev_ethtool(&ifr);
	set_fs(old_fs);
	
	if (!err) {
		switch(ecmd.speed) {
		case SPEED_100:
			return 19;
		case SPEED_1000:
			return 4;
		case SPEED_10000:
			return 2;
		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.
 * Called from work queue to allow for calling functions that
 * might sleep (such as speed check), and to debounce.
 */
static void port_carrier_check(void *arg)
{
	struct net_device *dev = arg;
	struct net_bridge_port *p;
	struct net_bridge *br;

	rtnl_lock();
	p = dev->br_port;
	if (!p)
		goto done;
	br = p->br;

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

	if (br->dev->flags & IFF_UP) {
		spin_lock_bh(&br->lock);
		if (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);
	}
done:
	rtnl_unlock();
}

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, dev->name);

	dev_set_promiscuity(dev, -1);

	cancel_delayed_work(&p->carrier_check);

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

	br_fdb_delete_by_port(br, p);

	list_del_rcu(&p->list);

	rcu_assign_pointer(dev->br_port, NULL);

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

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

/* called with RTNL */
static void del_br(struct net_bridge *br)
{
	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(br->dev);
}

static struct net_device *new_bridge_dev(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;

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

	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 = 0;
	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;
	INIT_LIST_HEAD(&br->age_list);

	br_stp_timer_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;
	br_init_port(p);
	p->state = BR_STATE_DISABLED;
	INIT_WORK(&p->carrier_check, port_carrier_check, dev);
	br_stp_port_timer_init(p);

	kobject_init(&p->kobj);
	kobject_set_name(&p->kobj, SYSFS_BRIDGE_PORT_ATTR);
	p->kobj.ktype = &brport_ktype;
	p->kobj.parent = &(dev->class_dev.kobj);
	p->kobj.kset = NULL;

	return p;
}

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

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

	rtnl_lock();
	if (strchr(dev->name, '%')) {
		ret = dev_alloc_name(dev, dev->name);
		if (ret < 0)
			goto err1;
	}

	ret = register_netdevice(dev);
	if (ret)
		goto err2;

	ret = br_sysfs_addbr(dev);
	if (ret)
		goto err3;
	rtnl_unlock();
	return 0;

 err3:
	unregister_netdev(dev);
 err2:
	free_netdev(dev);
 err1:
	rtnl_unlock();
	return ret;
}

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

	rtnl_lock();
	dev = __dev_get_by_name(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));

	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, checksum;

	features = br->feature_mask &~ NETIF_F_IP_CSUM;
	checksum = br->feature_mask & NETIF_F_IP_CSUM;

	list_for_each_entry(p, &br->port_list, list) {
		if (!(p->dev->features 
		      & (NETIF_F_IP_CSUM|NETIF_F_NO_CSUM|NETIF_F_HW_CSUM)))
			checksum = 0;
		features &= p->dev->features;
	}

	br->dev->features = features | checksum | NETIF_F_LLTX;
}

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

	if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER)
		return -EINVAL;

	if (dev->hard_start_xmit == br_dev_xmit)
		return -ELOOP;

	if (dev->br_port != NULL)
		return -EBUSY;

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

	err = kobject_add(&p->kobj);
	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;

	rcu_assign_pointer(dev->br_port, p);
	dev_set_promiscuity(dev, 1);

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

	spin_lock_bh(&br->lock);
	br_stp_recalculate_bridge_id(br);
	br_features_recompute(br);
	schedule_delayed_work(&p->carrier_check, BR_PORT_DEBOUNCE);
	spin_unlock_bh(&br->lock);

	dev_set_mtu(br->dev, br_min_mtu(br));
	kobject_uevent(&p->kobj, KOBJ_ADD);

	return 0;
err2:
	br_fdb_delete_by_port(br, p);
err1:
	kobject_del(&p->kobj);
err0:
	kobject_put(&p->kobj);
	return err;
}

/* called with RTNL */
int br_del_if(struct net_bridge *br, struct net_device *dev)
{
	struct net_bridge_port *p = dev->br_port;
	
	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 __exit br_cleanup_bridges(void)
{
	struct net_device *dev, *nxt;

	rtnl_lock();
	for (dev = dev_base; dev; dev = nxt) {
		nxt = dev->next;
		if (dev->priv_flags & IFF_EBRIDGE)
			del_br(dev->priv);
	}
	rtnl_unlock();

}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Userspace interface
	3	* Linux ethernet bridge
	4	*
	5	* Authors:
	6	* Lennert Buytenhek <buytenh@gnu.org>
	7	*
	8	* $Id: br_if.c,v 1.7 2001/12/24 00:59:55 davem Exp $
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public License
	12	* as published by the Free Software Foundation; either version
	13	* 2 of the License, or (at your option) any later version.
	14	*/
	15
	16	#include <linux/kernel.h>
	17	#include <linux/netdevice.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>
46f25dff	23	#include <linux/if_ether.h>
1da177e4 LT	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	* Need to simulate user ioctl because not all device's that support
	33	* ethtool, use ethtool_ops. Also, since driver might sleep need to
	34	* not be holding any locks.
	35	*/
4433f420	36	static int port_cost(struct net_device *dev)
1da177e4	37	{
1da177e4 LT	38	struct ethtool_cmd ecmd = { ETHTOOL_GSET };
	39	struct ifreq ifr;
	40	mm_segment_t old_fs;
	41	int err;
	42
	43	strncpy(ifr.ifr_name, dev->name, IFNAMSIZ);
	44	ifr.ifr_data = (void __user *) &ecmd;
	45
	46	old_fs = get_fs();
	47	set_fs(KERNEL_DS);
	48	err = dev_ethtool(&ifr);
	49	set_fs(old_fs);
	50
	51	if (!err) {
	52	switch(ecmd.speed) {
	53	case SPEED_100:
	54	return 19;
	55	case SPEED_1000:
	56	return 4;
	57	case SPEED_10000:
	58	return 2;
	59	case SPEED_10:
	60	return 100;
1da177e4 LT	61	}
	62	}
	63
	64	/* Old silly heuristics based on name */
	65	if (!strncmp(dev->name, "lec", 3))
	66	return 7;
	67
	68	if (!strncmp(dev->name, "plip", 4))
	69	return 2500;
	70
	71	return 100; /* assume old 10Mbps */
	72	}
	73
4433f420 SH	74
	75	/*
	76	* Check for port carrier transistions.
	77	* Called from work queue to allow for calling functions that
	78	* might sleep (such as speed check), and to debounce.
	79	*/
	80	static void port_carrier_check(void *arg)
	81	{
b3f1be4b SH	82	struct net_device *dev = arg;
b3f1be4b SH	83	struct net_bridge_port *p;
6e86b890	84	struct net_bridge *br;
4433f420 SH	85
4433f420 SH	86	rtnl_lock();
b3f1be4b SH	87	p = dev->br_port;
	88	if (!p)
	89	goto done;
6e86b890 SH	90	br = p->br;
	91
	92	if (netif_carrier_ok(dev))
	93	p->path_cost = port_cost(dev);
	94
	95	if (br->dev->flags & IFF_UP) {
	96	spin_lock_bh(&br->lock);
	97	if (netif_carrier_ok(dev)) {
	98	if (p->state == BR_STATE_DISABLED)
	99	br_stp_enable_port(p);
	100	} else {
	101	if (p->state != BR_STATE_DISABLED)
	102	br_stp_disable_port(p);
4433f420	103	}
6e86b890	104	spin_unlock_bh(&br->lock);
4433f420	105	}
b3f1be4b	106	done:
4433f420 SH	107	rtnl_unlock();
	108	}
	109
bab1deea SH	110	static void release_nbp(struct kobject *kobj)
	111	{
	112	struct net_bridge_port *p
	113	= container_of(kobj, struct net_bridge_port, kobj);
	114	kfree(p);
	115	}
	116
	117	static struct kobj_type brport_ktype = {
	118	#ifdef CONFIG_SYSFS
	119	.sysfs_ops = &brport_sysfs_ops,
	120	#endif
	121	.release = release_nbp,
	122	};
	123
1da177e4 LT	124	static void destroy_nbp(struct net_bridge_port *p)
	125	{
	126	struct net_device *dev = p->dev;
	127
1da177e4 LT	128	p->br = NULL;
	129	p->dev = NULL;
	130	dev_put(dev);
	131
bab1deea	132	kobject_put(&p->kobj);
1da177e4 LT	133	}
	134
	135	static void destroy_nbp_rcu(struct rcu_head *head)
	136	{
	137	struct net_bridge_port *p =
	138	container_of(head, struct net_bridge_port, rcu);
	139	destroy_nbp(p);
	140	}
	141
3f4cfc2d SH	142	/* Delete port(interface) from bridge is done in two steps.
	143	* via RCU. First step, marks device as down. That deletes
	144	* all the timers and stops new packets from flowing through.
	145	*
	146	* Final cleanup doesn't occur until after all CPU's finished
	147	* processing packets.
	148	*
	149	* Protected from multiple admin operations by RTNL mutex
	150	*/
1da177e4 LT	151	static void del_nbp(struct net_bridge_port *p)
	152	{
	153	struct net_bridge *br = p->br;
	154	struct net_device *dev = p->dev;
	155
bab1deea SH	156	sysfs_remove_link(&br->ifobj, dev->name);
bab1deea SH	157
1da177e4 LT	158	dev_set_promiscuity(dev, -1);
1da177e4 LT	159
4433f420	160	cancel_delayed_work(&p->carrier_check);
4433f420	161
1da177e4 LT	162	spin_lock_bh(&br->lock);
	163	br_stp_disable_port(p);
	164	spin_unlock_bh(&br->lock);
	165
	166	br_fdb_delete_by_port(br, p);
	167
	168	list_del_rcu(&p->list);
	169
b3f1be4b SH	170	rcu_assign_pointer(dev->br_port, NULL);
b3f1be4b SH	171
125a12cc	172	kobject_uevent(&p->kobj, KOBJ_REMOVE);
bab1deea SH	173	kobject_del(&p->kobj);
bab1deea SH	174
1da177e4 LT	175	call_rcu(&p->rcu, destroy_nbp_rcu);
	176	}
	177
	178	/* called with RTNL */
	179	static void del_br(struct net_bridge *br)
	180	{
	181	struct net_bridge_port p, n;
	182
	183	list_for_each_entry_safe(p, n, &br->port_list, list) {
1da177e4 LT	184	del_nbp(p);
	185	}
	186
	187	del_timer_sync(&br->gc_timer);
	188
	189	br_sysfs_delbr(br->dev);
	190	unregister_netdevice(br->dev);
	191	}
	192
	193	static struct net_device new_bridge_dev(const char name)
	194	{
	195	struct net_bridge *br;
	196	struct net_device *dev;
	197
	198	dev = alloc_netdev(sizeof(struct net_bridge), name,
	199	br_dev_setup);
	200
	201	if (!dev)
	202	return NULL;
	203
	204	br = netdev_priv(dev);
	205	br->dev = dev;
	206
	207	spin_lock_init(&br->lock);
	208	INIT_LIST_HEAD(&br->port_list);
	209	spin_lock_init(&br->hash_lock);
	210
	211	br->bridge_id.prio[0] = 0x80;
	212	br->bridge_id.prio[1] = 0x00;
cee48541 SH	213
cee48541 SH	214	memcpy(br->group_addr, br_group_address, ETH_ALEN);
1da177e4	215
edb5e46f	216	br->feature_mask = dev->features;
1da177e4 LT	217	br->stp_enabled = 0;
	218	br->designated_root = br->bridge_id;
	219	br->root_path_cost = 0;
	220	br->root_port = 0;
	221	br->bridge_max_age = br->max_age = 20 * HZ;
	222	br->bridge_hello_time = br->hello_time = 2 * HZ;
	223	br->bridge_forward_delay = br->forward_delay = 15 * HZ;
	224	br->topology_change = 0;
	225	br->topology_change_detected = 0;
	226	br->ageing_time = 300 * HZ;
	227	INIT_LIST_HEAD(&br->age_list);
	228
	229	br_stp_timer_init(br);
	230
	231	return dev;
	232	}
	233
	234	/* find an available port number */
	235	static int find_portno(struct net_bridge *br)
	236	{
	237	int index;
	238	struct net_bridge_port *p;
	239	unsigned long *inuse;
	240
3b781fa1	241	inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
1da177e4 LT	242	GFP_KERNEL);
	243	if (!inuse)
	244	return -ENOMEM;
	245
1da177e4 LT	246	set_bit(0, inuse); /* zero is reserved */
	247	list_for_each_entry(p, &br->port_list, list) {
	248	set_bit(p->port_no, inuse);
	249	}
	250	index = find_first_zero_bit(inuse, BR_MAX_PORTS);
	251	kfree(inuse);
	252
	253	return (index >= BR_MAX_PORTS) ? -EXFULL : index;
	254	}
	255
4433f420	256	/* called with RTNL but without bridge lock */
1da177e4	257	static struct net_bridge_port new_nbp(struct net_bridge br,
4433f420	258	struct net_device *dev)
1da177e4 LT	259	{
	260	int index;
	261	struct net_bridge_port *p;
	262
	263	index = find_portno(br);
	264	if (index < 0)
	265	return ERR_PTR(index);
	266
cee48541	267	p = kzalloc(sizeof(*p), GFP_KERNEL);
1da177e4 LT	268	if (p == NULL)
	269	return ERR_PTR(-ENOMEM);
	270
1da177e4 LT	271	p->br = br;
	272	dev_hold(dev);
	273	p->dev = dev;
4433f420	274	p->path_cost = port_cost(dev);
1da177e4	275	p->priority = 0x8000 >> BR_PORT_BITS;
1da177e4 LT	276	p->port_no = index;
	277	br_init_port(p);
	278	p->state = BR_STATE_DISABLED;
b3f1be4b	279	INIT_WORK(&p->carrier_check, port_carrier_check, dev);
d32439c0	280	br_stp_port_timer_init(p);
1da177e4	281
d32439c0	282	kobject_init(&p->kobj);
bab1deea SH	283	kobject_set_name(&p->kobj, SYSFS_BRIDGE_PORT_ATTR);
	284	p->kobj.ktype = &brport_ktype;
	285	p->kobj.parent = &(dev->class_dev.kobj);
	286	p->kobj.kset = NULL;
	287
1da177e4 LT	288	return p;
	289	}
	290
	291	int br_add_bridge(const char *name)
	292	{
	293	struct net_device *dev;
	294	int ret;
	295
	296	dev = new_bridge_dev(name);
	297	if (!dev)
	298	return -ENOMEM;
	299
	300	rtnl_lock();
	301	if (strchr(dev->name, '%')) {
	302	ret = dev_alloc_name(dev, dev->name);
	303	if (ret < 0)
	304	goto err1;
	305	}
	306
	307	ret = register_netdevice(dev);
	308	if (ret)
	309	goto err2;
	310
1da177e4	311	ret = br_sysfs_addbr(dev);
ac05202e SH	312	if (ret)
	313	goto err3;
	314	rtnl_unlock();
	315	return 0;
1da177e4	316
ac05202e SH	317	err3:
ac05202e SH	318	unregister_netdev(dev);
1da177e4 LT	319	err2:
	320	free_netdev(dev);
	321	err1:
	322	rtnl_unlock();
ac05202e	323	return ret;
1da177e4 LT	324	}
	325
	326	int br_del_bridge(const char *name)
	327	{
	328	struct net_device *dev;
	329	int ret = 0;
	330
	331	rtnl_lock();
	332	dev = __dev_get_by_name(name);
	333	if (dev == NULL)
	334	ret = -ENXIO; /* Could not find device */
	335
	336	else if (!(dev->priv_flags & IFF_EBRIDGE)) {
	337	/* Attempt to delete non bridge device! */
	338	ret = -EPERM;
	339	}
	340
	341	else if (dev->flags & IFF_UP) {
	342	/* Not shutdown yet. */
	343	ret = -EBUSY;
	344	}
	345
	346	else
	347	del_br(netdev_priv(dev));
	348
	349	rtnl_unlock();
	350	return ret;
	351	}
	352
46f25dff	353	/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
1da177e4 LT	354	int br_min_mtu(const struct net_bridge *br)
	355	{
	356	const struct net_bridge_port *p;
	357	int mtu = 0;
	358
	359	ASSERT_RTNL();
	360
	361	if (list_empty(&br->port_list))
46f25dff	362	mtu = ETH_DATA_LEN;
1da177e4 LT	363	else {
	364	list_for_each_entry(p, &br->port_list, list) {
	365	if (!mtu \|\| p->dev->mtu < mtu)
	366	mtu = p->dev->mtu;
	367	}
	368	}
	369	return mtu;
	370	}
	371
81d35307 SH	372	/*
	373	* Recomputes features using slave's features
	374	*/
	375	void br_features_recompute(struct net_bridge *br)
	376	{
	377	struct net_bridge_port *p;
	378	unsigned long features, checksum;
	379
edb5e46f SH	380	features = br->feature_mask &~ NETIF_F_IP_CSUM;
edb5e46f SH	381	checksum = br->feature_mask & NETIF_F_IP_CSUM;
81d35307 SH	382
	383	list_for_each_entry(p, &br->port_list, list) {
	384	if (!(p->dev->features
	385	& (NETIF_F_IP_CSUM\|NETIF_F_NO_CSUM\|NETIF_F_HW_CSUM)))
	386	checksum = 0;
	387	features &= p->dev->features;
	388	}
	389
	390	br->dev->features = features \| checksum \| NETIF_F_LLTX;
	391	}
	392
1da177e4 LT	393	/* called with RTNL */
	394	int br_add_if(struct net_bridge br, struct net_device dev)
	395	{
	396	struct net_bridge_port *p;
	397	int err = 0;
	398
	399	if (dev->flags & IFF_LOOPBACK \|\| dev->type != ARPHRD_ETHER)
	400	return -EINVAL;
	401
	402	if (dev->hard_start_xmit == br_dev_xmit)
	403	return -ELOOP;
	404
	405	if (dev->br_port != NULL)
	406	return -EBUSY;
	407
bab1deea SH	408	p = new_nbp(br, dev);
bab1deea SH	409	if (IS_ERR(p))
1da177e4 LT	410	return PTR_ERR(p);
1da177e4 LT	411
bab1deea SH	412	err = kobject_add(&p->kobj);
	413	if (err)
	414	goto err0;
1da177e4	415
bab1deea SH	416	err = br_fdb_insert(br, p, dev->dev_addr);
	417	if (err)
	418	goto err1;
1da177e4	419
bab1deea SH	420	err = br_sysfs_addif(p);
	421	if (err)
	422	goto err2;
1da177e4	423
bab1deea SH	424	rcu_assign_pointer(dev->br_port, p);
	425	dev_set_promiscuity(dev, 1);
	426
	427	list_add_rcu(&p->list, &br->port_list);
	428
	429	spin_lock_bh(&br->lock);
	430	br_stp_recalculate_bridge_id(br);
	431	br_features_recompute(br);
	432	schedule_delayed_work(&p->carrier_check, BR_PORT_DEBOUNCE);
	433	spin_unlock_bh(&br->lock);
	434
	435	dev_set_mtu(br->dev, br_min_mtu(br));
	436	kobject_uevent(&p->kobj, KOBJ_ADD);
1da177e4	437
bab1deea SH	438	return 0;
	439	err2:
	440	br_fdb_delete_by_port(br, p);
	441	err1:
	442	kobject_del(&p->kobj);
	443	err0:
	444	kobject_put(&p->kobj);
1da177e4 LT	445	return err;
	446	}
	447
	448	/* called with RTNL */
	449	int br_del_if(struct net_bridge br, struct net_device dev)
	450	{
	451	struct net_bridge_port *p = dev->br_port;
	452
	453	if (!p \|\| p->br != br)
	454	return -EINVAL;
	455
1da177e4 LT	456	del_nbp(p);
	457
	458	spin_lock_bh(&br->lock);
	459	br_stp_recalculate_bridge_id(br);
81d35307	460	br_features_recompute(br);
1da177e4 LT	461	spin_unlock_bh(&br->lock);
	462
	463	return 0;
	464	}
	465
	466	void __exit br_cleanup_bridges(void)
	467	{
	468	struct net_device dev, nxt;
	469
	470	rtnl_lock();
	471	for (dev = dev_base; dev; dev = nxt) {
	472	nxt = dev->next;
	473	if (dev->priv_flags & IFF_EBRIDGE)
	474	del_br(dev->priv);
	475	}
	476	rtnl_unlock();
	477
	478	}