[linux-2.6-block.git] / drivers / net / wan / lapbether.c

/*
 *	"LAPB via ethernet" driver release 001
 *
 *	This code REQUIRES 2.1.15 or higher/ NET3.038
 *
 *	This module:
 *		This module 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.
 *
 *	This is a "pseudo" network driver to allow LAPB over Ethernet.
 *
 *	This driver can use any ethernet destination address, and can be 
 *	limited to accept frames from one dedicated ethernet card only.
 *
 *	History
 *	LAPBETH 001	Jonathan Naylor		Cloned from bpqether.c
 *	2000-10-29	Henner Eisen	lapb_data_indication() return status.
 *	2000-11-14	Henner Eisen	dev_hold/put, NETDEV_GOING_DOWN support
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/net.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/stat.h>
#include <linux/netfilter.h>
#include <linux/module.h>
#include <linux/lapb.h>
#include <linux/init.h>

#include <net/x25device.h>

static const u8 bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };

/* If this number is made larger, check that the temporary string buffer
 * in lapbeth_new_device is large enough to store the probe device name.*/
#define MAXLAPBDEV 100

struct lapbethdev {
	struct list_head	node;
	struct net_device	*ethdev;	/* link to ethernet device */
	struct net_device	*axdev;		/* lapbeth device (lapb#) */
};

static LIST_HEAD(lapbeth_devices);

/* ------------------------------------------------------------------------ */

/*
 *	Get the LAPB device for the ethernet device
 */
static struct lapbethdev *lapbeth_get_x25_dev(struct net_device *dev)
{
	struct lapbethdev *lapbeth;

	list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
		if (lapbeth->ethdev == dev) 
			return lapbeth;
	}
	return NULL;
}

static __inline__ int dev_is_ethdev(struct net_device *dev)
{
	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
}

/* ------------------------------------------------------------------------ */

/*
 *	Receive a LAPB frame via an ethernet interface.
 */
static int lapbeth_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev)
{
	int len, err;
	struct lapbethdev *lapbeth;

	if (dev_net(dev) != &init_net)
		goto drop;

	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
		return NET_RX_DROP;

	if (!pskb_may_pull(skb, 2))
		goto drop;

	rcu_read_lock();
	lapbeth = lapbeth_get_x25_dev(dev);
	if (!lapbeth)
		goto drop_unlock;
	if (!netif_running(lapbeth->axdev))
		goto drop_unlock;

	len = skb->data[0] + skb->data[1] * 256;
	dev->stats.rx_packets++;
	dev->stats.rx_bytes += len;

	skb_pull(skb, 2);	/* Remove the length bytes */
	skb_trim(skb, len);	/* Set the length of the data */

	if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
		printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
		goto drop_unlock;
	}
out:
	rcu_read_unlock();
	return 0;
drop_unlock:
	kfree_skb(skb);
	goto out;
drop:
	kfree_skb(skb);
	return 0;
}

static int lapbeth_data_indication(struct net_device *dev, struct sk_buff *skb)
{
	unsigned char *ptr;

	skb_push(skb, 1);

	if (skb_cow(skb, 1))
		return NET_RX_DROP;

	ptr  = skb->data;
	*ptr = X25_IFACE_DATA;

	skb->protocol = x25_type_trans(skb, dev);
	return netif_rx(skb);
}

/*
 *	Send a LAPB frame via an ethernet interface
 */
static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
				      struct net_device *dev)
{
	int err;

	/*
	 * Just to be *really* sure not to send anything if the interface
	 * is down, the ethernet device may have gone.
	 */
	if (!netif_running(dev))
		goto drop;

	switch (skb->data[0]) {
	case X25_IFACE_DATA:
		break;
	case X25_IFACE_CONNECT:
		if ((err = lapb_connect_request(dev)) != LAPB_OK)
			pr_err("lapb_connect_request error: %d\n", err);
		goto drop;
	case X25_IFACE_DISCONNECT:
		if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
			pr_err("lapb_disconnect_request err: %d\n", err);
		/* Fall thru */
	default:
		goto drop;
	}

	skb_pull(skb, 1);

	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
		pr_err("lapb_data_request error - %d\n", err);
		goto drop;
	}
out:
	return NETDEV_TX_OK;
drop:
	kfree_skb(skb);
	goto out;
}

static void lapbeth_data_transmit(struct net_device *ndev, struct sk_buff *skb)
{
	struct lapbethdev *lapbeth = netdev_priv(ndev);
	unsigned char *ptr;
	struct net_device *dev;
	int size = skb->len;

	skb->protocol = htons(ETH_P_X25);

	ptr = skb_push(skb, 2);

	*ptr++ = size % 256;
	*ptr++ = size / 256;

	ndev->stats.tx_packets++;
	ndev->stats.tx_bytes += size;

	skb->dev = dev = lapbeth->ethdev;

	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);

	dev_queue_xmit(skb);
}

static void lapbeth_connected(struct net_device *dev, int reason)
{
	unsigned char *ptr;
	struct sk_buff *skb = dev_alloc_skb(1);

	if (!skb) {
		pr_err("out of memory\n");
		return;
	}

	ptr  = skb_put(skb, 1);
	*ptr = X25_IFACE_CONNECT;

	skb->protocol = x25_type_trans(skb, dev);
	netif_rx(skb);
}

static void lapbeth_disconnected(struct net_device *dev, int reason)
{
	unsigned char *ptr;
	struct sk_buff *skb = dev_alloc_skb(1);

	if (!skb) {
		pr_err("out of memory\n");
		return;
	}

	ptr  = skb_put(skb, 1);
	*ptr = X25_IFACE_DISCONNECT;

	skb->protocol = x25_type_trans(skb, dev);
	netif_rx(skb);
}

/*
 *	Set AX.25 callsign
 */
static int lapbeth_set_mac_address(struct net_device *dev, void *addr)
{
	struct sockaddr *sa = addr;
	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
	return 0;
}


static const struct lapb_register_struct lapbeth_callbacks = {
	.connect_confirmation    = lapbeth_connected,
	.connect_indication      = lapbeth_connected,
	.disconnect_confirmation = lapbeth_disconnected,
	.disconnect_indication   = lapbeth_disconnected,
	.data_indication         = lapbeth_data_indication,
	.data_transmit           = lapbeth_data_transmit,
};

/*
 * open/close a device
 */
static int lapbeth_open(struct net_device *dev)
{
	int err;

	if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
		pr_err("lapb_register error: %d\n", err);
		return -ENODEV;
	}

	netif_start_queue(dev);
	return 0;
}

static int lapbeth_close(struct net_device *dev)
{
	int err;

	netif_stop_queue(dev);

	if ((err = lapb_unregister(dev)) != LAPB_OK)
		pr_err("lapb_unregister error: %d\n", err);

	return 0;
}

/* ------------------------------------------------------------------------ */

static const struct net_device_ops lapbeth_netdev_ops = {
	.ndo_open	     = lapbeth_open,
	.ndo_stop	     = lapbeth_close,
	.ndo_start_xmit	     = lapbeth_xmit,
	.ndo_set_mac_address = lapbeth_set_mac_address,
};

static void lapbeth_setup(struct net_device *dev)
{
	dev->netdev_ops	     = &lapbeth_netdev_ops;
	dev->destructor	     = free_netdev;
	dev->type            = ARPHRD_X25;
	dev->hard_header_len = 3;
	dev->mtu             = 1000;
	dev->addr_len        = 0;
}

/*
 *	Setup a new device.
 */
static int lapbeth_new_device(struct net_device *dev)
{
	struct net_device *ndev;
	struct lapbethdev *lapbeth;
	int rc = -ENOMEM;

	ASSERT_RTNL();

	ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d", 
			   lapbeth_setup);
	if (!ndev)
		goto out;

	lapbeth = netdev_priv(ndev);
	lapbeth->axdev = ndev;

	dev_hold(dev);
	lapbeth->ethdev = dev;

	rc = -EIO;
	if (register_netdevice(ndev))
		goto fail;

	list_add_rcu(&lapbeth->node, &lapbeth_devices);
	rc = 0;
out:
	return rc;
fail:
	dev_put(dev);
	free_netdev(ndev);
	kfree(lapbeth);
	goto out;
}

/*
 *	Free a lapb network device.
 */
static void lapbeth_free_device(struct lapbethdev *lapbeth)
{
	dev_put(lapbeth->ethdev);
	list_del_rcu(&lapbeth->node);
	unregister_netdevice(lapbeth->axdev);
}

/*
 *	Handle device status changes.
 *
 * Called from notifier with RTNL held.
 */
static int lapbeth_device_event(struct notifier_block *this,
				unsigned long event, void *ptr)
{
	struct lapbethdev *lapbeth;
	struct net_device *dev = ptr;

	if (dev_net(dev) != &init_net)
		return NOTIFY_DONE;

	if (!dev_is_ethdev(dev))
		return NOTIFY_DONE;

	switch (event) {
	case NETDEV_UP:
		/* New ethernet device -> new LAPB interface	 */
		if (lapbeth_get_x25_dev(dev) == NULL)
			lapbeth_new_device(dev);
		break;
	case NETDEV_DOWN:	
		/* ethernet device closed -> close LAPB interface */
		lapbeth = lapbeth_get_x25_dev(dev);
		if (lapbeth) 
			dev_close(lapbeth->axdev);
		break;
	case NETDEV_UNREGISTER:
		/* ethernet device disappears -> remove LAPB interface */
		lapbeth = lapbeth_get_x25_dev(dev);
		if (lapbeth)
			lapbeth_free_device(lapbeth);
		break;
	}

	return NOTIFY_DONE;
}

/* ------------------------------------------------------------------------ */

static struct packet_type lapbeth_packet_type __read_mostly = {
	.type = cpu_to_be16(ETH_P_DEC),
	.func = lapbeth_rcv,
};

static struct notifier_block lapbeth_dev_notifier = {
	.notifier_call = lapbeth_device_event,
};

static const char banner[] __initconst =
	KERN_INFO "LAPB Ethernet driver version 0.02\n";

static int __init lapbeth_init_driver(void)
{
	dev_add_pack(&lapbeth_packet_type);

	register_netdevice_notifier(&lapbeth_dev_notifier);

	printk(banner);

	return 0;
}
module_init(lapbeth_init_driver);

static void __exit lapbeth_cleanup_driver(void)
{
	struct lapbethdev *lapbeth;
	struct list_head *entry, *tmp;

	dev_remove_pack(&lapbeth_packet_type);
	unregister_netdevice_notifier(&lapbeth_dev_notifier);

	rtnl_lock();
	list_for_each_safe(entry, tmp, &lapbeth_devices) {
		lapbeth = list_entry(entry, struct lapbethdev, node);

		dev_put(lapbeth->ethdev);
		unregister_netdevice(lapbeth->axdev);
	}
	rtnl_unlock();
}
module_exit(lapbeth_cleanup_driver);

MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
	1	/*
	2	* "LAPB via ethernet" driver release 001
	3	*
	4	* This code REQUIRES 2.1.15 or higher/ NET3.038
	5	*
	6	* This module:
	7	* This module is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License
	9	* as published by the Free Software Foundation; either version
	10	* 2 of the License, or (at your option) any later version.
	11	*
	12	* This is a "pseudo" network driver to allow LAPB over Ethernet.
	13	*
	14	* This driver can use any ethernet destination address, and can be
	15	* limited to accept frames from one dedicated ethernet card only.
	16	*
	17	* History
	18	* LAPBETH 001 Jonathan Naylor Cloned from bpqether.c
	19	* 2000-10-29 Henner Eisen lapb_data_indication() return status.
	20	* 2000-11-14 Henner Eisen dev_hold/put, NETDEV_GOING_DOWN support
	21	*/
	22
	23	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	24
	25	#include <linux/errno.h>
	26	#include <linux/types.h>
	27	#include <linux/socket.h>
	28	#include <linux/in.h>
	29	#include <linux/slab.h>
	30	#include <linux/kernel.h>
	31	#include <linux/string.h>
	32	#include <linux/net.h>
	33	#include <linux/inet.h>
	34	#include <linux/netdevice.h>
	35	#include <linux/if_arp.h>
	36	#include <linux/skbuff.h>
	37	#include <net/sock.h>
	38	#include <asm/system.h>
	39	#include <asm/uaccess.h>
	40	#include <linux/mm.h>
	41	#include <linux/interrupt.h>
	42	#include <linux/notifier.h>
	43	#include <linux/stat.h>
	44	#include <linux/netfilter.h>
	45	#include <linux/module.h>
	46	#include <linux/lapb.h>
	47	#include <linux/init.h>
	48
	49	#include <net/x25device.h>
	50
	51	static const u8 bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
	52
	53	/* If this number is made larger, check that the temporary string buffer
	54	* in lapbeth_new_device is large enough to store the probe device name.*/
	55	#define MAXLAPBDEV 100
	56
	57	struct lapbethdev {
	58	struct list_head node;
	59	struct net_device ethdev; / link to ethernet device */
	60	struct net_device axdev; / lapbeth device (lapb#) */
	61	};
	62
	63	static LIST_HEAD(lapbeth_devices);
	64
	65	/* ------------------------------------------------------------------------ */
	66
	67	/*
	68	* Get the LAPB device for the ethernet device
	69	*/
	70	static struct lapbethdev lapbeth_get_x25_dev(struct net_device dev)
	71	{
	72	struct lapbethdev *lapbeth;
	73
	74	list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
	75	if (lapbeth->ethdev == dev)
	76	return lapbeth;
	77	}
	78	return NULL;
	79	}
	80
	81	static __inline__ int dev_is_ethdev(struct net_device *dev)
	82	{
	83	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
	84	}
	85
	86	/* ------------------------------------------------------------------------ */
	87
	88	/*
	89	* Receive a LAPB frame via an ethernet interface.
	90	*/
	91	static int lapbeth_rcv(struct sk_buff skb, struct net_device dev, struct packet_type ptype, struct net_device orig_dev)
	92	{
	93	int len, err;
	94	struct lapbethdev *lapbeth;
	95
	96	if (dev_net(dev) != &init_net)
	97	goto drop;
	98
	99	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
	100	return NET_RX_DROP;
	101
	102	if (!pskb_may_pull(skb, 2))
	103	goto drop;
	104
	105	rcu_read_lock();
	106	lapbeth = lapbeth_get_x25_dev(dev);
	107	if (!lapbeth)
	108	goto drop_unlock;
	109	if (!netif_running(lapbeth->axdev))
	110	goto drop_unlock;
	111
	112	len = skb->data[0] + skb->data[1] * 256;
	113	dev->stats.rx_packets++;
	114	dev->stats.rx_bytes += len;
	115
	116	skb_pull(skb, 2); /* Remove the length bytes */
	117	skb_trim(skb, len); /* Set the length of the data */
	118
	119	if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
	120	printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
	121	goto drop_unlock;
	122	}
	123	out:
	124	rcu_read_unlock();
	125	return 0;
	126	drop_unlock:
	127	kfree_skb(skb);
	128	goto out;
	129	drop:
	130	kfree_skb(skb);
	131	return 0;
	132	}
	133
	134	static int lapbeth_data_indication(struct net_device dev, struct sk_buff skb)
	135	{
	136	unsigned char *ptr;
	137
	138	skb_push(skb, 1);
	139
	140	if (skb_cow(skb, 1))
	141	return NET_RX_DROP;
	142
	143	ptr = skb->data;
	144	*ptr = X25_IFACE_DATA;
	145
	146	skb->protocol = x25_type_trans(skb, dev);
	147	return netif_rx(skb);
	148	}
	149
	150	/*
	151	* Send a LAPB frame via an ethernet interface
	152	*/
	153	static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
	154	struct net_device *dev)
	155	{
	156	int err;
	157
	158	/*
	159	* Just to be really sure not to send anything if the interface
	160	* is down, the ethernet device may have gone.
	161	*/
	162	if (!netif_running(dev))
	163	goto drop;
	164
	165	switch (skb->data[0]) {
	166	case X25_IFACE_DATA:
	167	break;
	168	case X25_IFACE_CONNECT:
	169	if ((err = lapb_connect_request(dev)) != LAPB_OK)
	170	pr_err("lapb_connect_request error: %d\n", err);
	171	goto drop;
	172	case X25_IFACE_DISCONNECT:
	173	if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
	174	pr_err("lapb_disconnect_request err: %d\n", err);
	175	/* Fall thru */
	176	default:
	177	goto drop;
	178	}
	179
	180	skb_pull(skb, 1);
	181
	182	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
	183	pr_err("lapb_data_request error - %d\n", err);
	184	goto drop;
	185	}
	186	out:
	187	return NETDEV_TX_OK;
	188	drop:
	189	kfree_skb(skb);
	190	goto out;
	191	}
	192
	193	static void lapbeth_data_transmit(struct net_device ndev, struct sk_buff skb)
	194	{
	195	struct lapbethdev *lapbeth = netdev_priv(ndev);
	196	unsigned char *ptr;
	197	struct net_device *dev;
	198	int size = skb->len;
	199
	200	skb->protocol = htons(ETH_P_X25);
	201
	202	ptr = skb_push(skb, 2);
	203
	204	*ptr++ = size % 256;
	205	*ptr++ = size / 256;
	206
	207	ndev->stats.tx_packets++;
	208	ndev->stats.tx_bytes += size;
	209
	210	skb->dev = dev = lapbeth->ethdev;
	211
	212	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
	213
	214	dev_queue_xmit(skb);
	215	}
	216
	217	static void lapbeth_connected(struct net_device *dev, int reason)
	218	{
	219	unsigned char *ptr;
	220	struct sk_buff *skb = dev_alloc_skb(1);
	221
	222	if (!skb) {
	223	pr_err("out of memory\n");
	224	return;
	225	}
	226
	227	ptr = skb_put(skb, 1);
	228	*ptr = X25_IFACE_CONNECT;
	229
	230	skb->protocol = x25_type_trans(skb, dev);
	231	netif_rx(skb);
	232	}
	233
	234	static void lapbeth_disconnected(struct net_device *dev, int reason)
	235	{
	236	unsigned char *ptr;
	237	struct sk_buff *skb = dev_alloc_skb(1);
	238
	239	if (!skb) {
	240	pr_err("out of memory\n");
	241	return;
	242	}
	243
	244	ptr = skb_put(skb, 1);
	245	*ptr = X25_IFACE_DISCONNECT;
	246
	247	skb->protocol = x25_type_trans(skb, dev);
	248	netif_rx(skb);
	249	}
	250
	251	/*
	252	* Set AX.25 callsign
	253	*/
	254	static int lapbeth_set_mac_address(struct net_device dev, void addr)
	255	{
	256	struct sockaddr *sa = addr;
	257	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
	258	return 0;
	259	}
	260
	261
	262	static const struct lapb_register_struct lapbeth_callbacks = {
	263	.connect_confirmation = lapbeth_connected,
	264	.connect_indication = lapbeth_connected,
	265	.disconnect_confirmation = lapbeth_disconnected,
	266	.disconnect_indication = lapbeth_disconnected,
	267	.data_indication = lapbeth_data_indication,
	268	.data_transmit = lapbeth_data_transmit,
	269	};
	270
	271	/*
	272	* open/close a device
	273	*/
	274	static int lapbeth_open(struct net_device *dev)
	275	{
	276	int err;
	277
	278	if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
	279	pr_err("lapb_register error: %d\n", err);
	280	return -ENODEV;
	281	}
	282
	283	netif_start_queue(dev);
	284	return 0;
	285	}
	286
	287	static int lapbeth_close(struct net_device *dev)
	288	{
	289	int err;
	290
	291	netif_stop_queue(dev);
	292
	293	if ((err = lapb_unregister(dev)) != LAPB_OK)
	294	pr_err("lapb_unregister error: %d\n", err);
	295
	296	return 0;
	297	}
	298
	299	/* ------------------------------------------------------------------------ */
	300
	301	static const struct net_device_ops lapbeth_netdev_ops = {
	302	.ndo_open = lapbeth_open,
	303	.ndo_stop = lapbeth_close,
	304	.ndo_start_xmit = lapbeth_xmit,
	305	.ndo_set_mac_address = lapbeth_set_mac_address,
	306	};
	307
	308	static void lapbeth_setup(struct net_device *dev)
	309	{
	310	dev->netdev_ops = &lapbeth_netdev_ops;
	311	dev->destructor = free_netdev;
	312	dev->type = ARPHRD_X25;
	313	dev->hard_header_len = 3;
	314	dev->mtu = 1000;
	315	dev->addr_len = 0;
	316	}
	317
	318	/*
	319	* Setup a new device.
	320	*/
	321	static int lapbeth_new_device(struct net_device *dev)
	322	{
	323	struct net_device *ndev;
	324	struct lapbethdev *lapbeth;
	325	int rc = -ENOMEM;
	326
	327	ASSERT_RTNL();
	328
	329	ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d",
	330	lapbeth_setup);
	331	if (!ndev)
	332	goto out;
	333
	334	lapbeth = netdev_priv(ndev);
	335	lapbeth->axdev = ndev;
	336
	337	dev_hold(dev);
	338	lapbeth->ethdev = dev;
	339
	340	rc = -EIO;
	341	if (register_netdevice(ndev))
	342	goto fail;
	343
	344	list_add_rcu(&lapbeth->node, &lapbeth_devices);
	345	rc = 0;
	346	out:
	347	return rc;
	348	fail:
	349	dev_put(dev);
	350	free_netdev(ndev);
	351	kfree(lapbeth);
	352	goto out;
	353	}
	354
	355	/*
	356	* Free a lapb network device.
	357	*/
	358	static void lapbeth_free_device(struct lapbethdev *lapbeth)
	359	{
	360	dev_put(lapbeth->ethdev);
	361	list_del_rcu(&lapbeth->node);
	362	unregister_netdevice(lapbeth->axdev);
	363	}
	364
	365	/*
	366	* Handle device status changes.
	367	*
	368	* Called from notifier with RTNL held.
	369	*/
	370	static int lapbeth_device_event(struct notifier_block *this,
	371	unsigned long event, void *ptr)
	372	{
	373	struct lapbethdev *lapbeth;
	374	struct net_device *dev = ptr;
	375
	376	if (dev_net(dev) != &init_net)
	377	return NOTIFY_DONE;
	378
	379	if (!dev_is_ethdev(dev))
	380	return NOTIFY_DONE;
	381
	382	switch (event) {
	383	case NETDEV_UP:
	384	/* New ethernet device -> new LAPB interface */
	385	if (lapbeth_get_x25_dev(dev) == NULL)
	386	lapbeth_new_device(dev);
	387	break;
	388	case NETDEV_DOWN:
	389	/* ethernet device closed -> close LAPB interface */
	390	lapbeth = lapbeth_get_x25_dev(dev);
	391	if (lapbeth)
	392	dev_close(lapbeth->axdev);
	393	break;
	394	case NETDEV_UNREGISTER:
	395	/* ethernet device disappears -> remove LAPB interface */
	396	lapbeth = lapbeth_get_x25_dev(dev);
	397	if (lapbeth)
	398	lapbeth_free_device(lapbeth);
	399	break;
	400	}
	401
	402	return NOTIFY_DONE;
	403	}
	404
	405	/* ------------------------------------------------------------------------ */
	406
	407	static struct packet_type lapbeth_packet_type __read_mostly = {
	408	.type = cpu_to_be16(ETH_P_DEC),
	409	.func = lapbeth_rcv,
	410	};
	411
	412	static struct notifier_block lapbeth_dev_notifier = {
	413	.notifier_call = lapbeth_device_event,
	414	};
	415
	416	static const char banner[] __initconst =
	417	KERN_INFO "LAPB Ethernet driver version 0.02\n";
	418
	419	static int __init lapbeth_init_driver(void)
	420	{
	421	dev_add_pack(&lapbeth_packet_type);
	422
	423	register_netdevice_notifier(&lapbeth_dev_notifier);
	424
	425	printk(banner);
	426
	427	return 0;
	428	}
	429	module_init(lapbeth_init_driver);
	430
	431	static void __exit lapbeth_cleanup_driver(void)
	432	{
	433	struct lapbethdev *lapbeth;
	434	struct list_head entry, tmp;
	435
	436	dev_remove_pack(&lapbeth_packet_type);
	437	unregister_netdevice_notifier(&lapbeth_dev_notifier);
	438
	439	rtnl_lock();
	440	list_for_each_safe(entry, tmp, &lapbeth_devices) {
	441	lapbeth = list_entry(entry, struct lapbethdev, node);
	442
	443	dev_put(lapbeth->ethdev);
	444	unregister_netdevice(lapbeth->axdev);
	445	}
	446	rtnl_unlock();
	447	}
	448	module_exit(lapbeth_cleanup_driver);
	449
	450	MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
	451	MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
	452	MODULE_LICENSE("GPL");