[net-next-2.6.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
 */

#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 char 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 = 0x00;

	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 0x00:
		break;
	case 0x01:
		if ((err = lapb_connect_request(dev)) != LAPB_OK)
			printk(KERN_ERR "lapbeth: lapb_connect_request "
			       "error: %d\n", err);
		goto drop;
	case 0x02:
		if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
			printk(KERN_ERR "lapbeth: 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) {
		printk(KERN_ERR "lapbeth: 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) {
		printk(KERN_ERR "lapbeth: out of memory\n");
		return;
	}

	ptr  = skb_put(skb, 1);
	*ptr = 0x01;

	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) {
		printk(KERN_ERR "lapbeth: out of memory\n");
		return;
	}

	ptr  = skb_put(skb, 1);
	*ptr = 0x02;

	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 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) {
		printk(KERN_ERR "lapbeth: 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)
		printk(KERN_ERR "lapbeth: 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 = dev_alloc_name(ndev, ndev->name);
	if (rc < 0) 
		goto fail;

	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
1da177e4 LT	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	#include <linux/errno.h>
	24	#include <linux/types.h>
	25	#include <linux/socket.h>
	26	#include <linux/in.h>
5a0e3ad6	27	#include <linux/slab.h>
1da177e4 LT	28	#include <linux/kernel.h>
	29	#include <linux/string.h>
	30	#include <linux/net.h>
	31	#include <linux/inet.h>
	32	#include <linux/netdevice.h>
	33	#include <linux/if_arp.h>
	34	#include <linux/skbuff.h>
	35	#include <net/sock.h>
	36	#include <asm/system.h>
	37	#include <asm/uaccess.h>
	38	#include <linux/mm.h>
	39	#include <linux/interrupt.h>
	40	#include <linux/notifier.h>
	41	#include <linux/stat.h>
	42	#include <linux/netfilter.h>
	43	#include <linux/module.h>
	44	#include <linux/lapb.h>
	45	#include <linux/init.h>
	46
	47	#include <net/x25device.h>
	48
	49	static char bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
	50
	51	/* If this number is made larger, check that the temporary string buffer
	52	* in lapbeth_new_device is large enough to store the probe device name.*/
	53	#define MAXLAPBDEV 100
	54
	55	struct lapbethdev {
	56	struct list_head node;
	57	struct net_device ethdev; / link to ethernet device */
	58	struct net_device axdev; / lapbeth device (lapb#) */
1da177e4 LT	59	};
1da177e4 LT	60
293a3839	61	static LIST_HEAD(lapbeth_devices);
1da177e4 LT	62
	63	/* ------------------------------------------------------------------------ */
	64
	65	/*
	66	* Get the LAPB device for the ethernet device
	67	*/
	68	static struct lapbethdev lapbeth_get_x25_dev(struct net_device dev)
	69	{
	70	struct lapbethdev *lapbeth;
	71
	72	list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
	73	if (lapbeth->ethdev == dev)
	74	return lapbeth;
	75	}
	76	return NULL;
	77	}
	78
	79	static __inline__ int dev_is_ethdev(struct net_device *dev)
	80	{
	81	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
	82	}
	83
	84	/* ------------------------------------------------------------------------ */
	85
	86	/*
	87	* Receive a LAPB frame via an ethernet interface.
	88	*/
f2ccd8fa	89	static int lapbeth_rcv(struct sk_buff skb, struct net_device dev, struct packet_type ptype, struct net_device orig_dev)
1da177e4 LT	90	{
	91	int len, err;
	92	struct lapbethdev *lapbeth;
	93
c346dca1	94	if (dev_net(dev) != &init_net)
e730c155 EB	95	goto drop;
e730c155 EB	96
1da177e4 LT	97	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
	98	return NET_RX_DROP;
	99
	100	if (!pskb_may_pull(skb, 2))
	101	goto drop;
	102
	103	rcu_read_lock();
	104	lapbeth = lapbeth_get_x25_dev(dev);
	105	if (!lapbeth)
	106	goto drop_unlock;
	107	if (!netif_running(lapbeth->axdev))
	108	goto drop_unlock;
	109
1da177e4	110	len = skb->data[0] + skb->data[1] * 256;
ea2ebaf8 SH	111	dev->stats.rx_packets++;
ea2ebaf8 SH	112	dev->stats.rx_bytes += len;
1da177e4 LT	113
	114	skb_pull(skb, 2); /* Remove the length bytes */
	115	skb_trim(skb, len); /* Set the length of the data */
	116
	117	if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
	118	printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
	119	goto drop_unlock;
	120	}
	121	out:
	122	rcu_read_unlock();
	123	return 0;
	124	drop_unlock:
	125	kfree_skb(skb);
	126	goto out;
	127	drop:
	128	kfree_skb(skb);
	129	return 0;
	130	}
	131
	132	static int lapbeth_data_indication(struct net_device dev, struct sk_buff skb)
	133	{
	134	unsigned char *ptr;
	135
	136	skb_push(skb, 1);
	137
	138	if (skb_cow(skb, 1))
	139	return NET_RX_DROP;
	140
	141	ptr = skb->data;
	142	*ptr = 0x00;
	143
	144	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	145	return netif_rx(skb);
	146	}
	147
	148	/*
	149	* Send a LAPB frame via an ethernet interface
	150	*/
d71a6749 SH	151	static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
d71a6749 SH	152	struct net_device *dev)
1da177e4	153	{
d77eeb70	154	int err;
1da177e4 LT	155
	156	/*
	157	* Just to be really sure not to send anything if the interface
	158	* is down, the ethernet device may have gone.
	159	*/
d77eeb70	160	if (!netif_running(dev))
1da177e4	161	goto drop;
1da177e4 LT	162
	163	switch (skb->data[0]) {
	164	case 0x00:
1da177e4 LT	165	break;
	166	case 0x01:
	167	if ((err = lapb_connect_request(dev)) != LAPB_OK)
	168	printk(KERN_ERR "lapbeth: lapb_connect_request "
	169	"error: %d\n", err);
d77eeb70	170	goto drop;
1da177e4 LT	171	case 0x02:
	172	if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
	173	printk(KERN_ERR "lapbeth: lapb_disconnect_request "
	174	"err: %d\n", err);
	175	/* Fall thru */
	176	default:
d77eeb70	177	goto drop;
1da177e4 LT	178	}
	179
	180	skb_pull(skb, 1);
	181
	182	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
	183	printk(KERN_ERR "lapbeth: lapb_data_request error - %d\n", err);
1da177e4 LT	184	goto drop;
1da177e4 LT	185	}
1da177e4	186	out:
d77eeb70	187	return NETDEV_TX_OK;
1da177e4 LT	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
ea2ebaf8 SH	207	ndev->stats.tx_packets++;
ea2ebaf8 SH	208	ndev->stats.tx_bytes += size;
1da177e4 LT	209
	210	skb->dev = dev = lapbeth->ethdev;
	211
0c4e8581	212	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
1da177e4 LT	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	printk(KERN_ERR "lapbeth: out of memory\n");
	224	return;
	225	}
	226
	227	ptr = skb_put(skb, 1);
	228	*ptr = 0x01;
	229
	230	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	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	printk(KERN_ERR "lapbeth: out of memory\n");
	241	return;
	242	}
	243
	244	ptr = skb_put(skb, 1);
	245	*ptr = 0x02;
	246
	247	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	248	netif_rx(skb);
	249	}
	250
1da177e4 LT	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 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	/*
	273	* open/close a device
	274	*/
	275	static int lapbeth_open(struct net_device *dev)
	276	{
	277	int err;
	278
	279	if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
	280	printk(KERN_ERR "lapbeth: lapb_register error - %d\n", err);
	281	return -ENODEV;
	282	}
	283
	284	netif_start_queue(dev);
	285	return 0;
	286	}
	287
	288	static int lapbeth_close(struct net_device *dev)
	289	{
	290	int err;
	291
	292	netif_stop_queue(dev);
	293
	294	if ((err = lapb_unregister(dev)) != LAPB_OK)
	295	printk(KERN_ERR "lapbeth: lapb_unregister error - %d\n", err);
	296
	297	return 0;
	298	}
	299
	300	/* ------------------------------------------------------------------------ */
	301
39549b1e SH	302	static const struct net_device_ops lapbeth_netdev_ops = {
	303	.ndo_open = lapbeth_open,
	304	.ndo_stop = lapbeth_close,
	305	.ndo_start_xmit = lapbeth_xmit,
	306	.ndo_set_mac_address = lapbeth_set_mac_address,
	307	};
	308
1da177e4 LT	309	static void lapbeth_setup(struct net_device *dev)
1da177e4 LT	310	{
39549b1e	311	dev->netdev_ops = &lapbeth_netdev_ops;
1da177e4	312	dev->destructor = free_netdev;
1da177e4 LT	313	dev->type = ARPHRD_X25;
	314	dev->hard_header_len = 3;
	315	dev->mtu = 1000;
	316	dev->addr_len = 0;
1da177e4 LT	317	}
	318
	319	/*
	320	* Setup a new device.
	321	*/
	322	static int lapbeth_new_device(struct net_device *dev)
	323	{
	324	struct net_device *ndev;
	325	struct lapbethdev *lapbeth;
	326	int rc = -ENOMEM;
	327
	328	ASSERT_RTNL();
	329
	330	ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d",
	331	lapbeth_setup);
	332	if (!ndev)
	333	goto out;
	334
	335	lapbeth = netdev_priv(ndev);
	336	lapbeth->axdev = ndev;
	337
	338	dev_hold(dev);
	339	lapbeth->ethdev = dev;
	340
	341	rc = dev_alloc_name(ndev, ndev->name);
	342	if (rc < 0)
	343	goto fail;
	344
	345	rc = -EIO;
	346	if (register_netdevice(ndev))
	347	goto fail;
	348
	349	list_add_rcu(&lapbeth->node, &lapbeth_devices);
	350	rc = 0;
	351	out:
	352	return rc;
	353	fail:
	354	dev_put(dev);
	355	free_netdev(ndev);
	356	kfree(lapbeth);
	357	goto out;
	358	}
	359
	360	/*
	361	* Free a lapb network device.
	362	*/
	363	static void lapbeth_free_device(struct lapbethdev *lapbeth)
	364	{
	365	dev_put(lapbeth->ethdev);
	366	list_del_rcu(&lapbeth->node);
	367	unregister_netdevice(lapbeth->axdev);
	368	}
	369
	370	/*
	371	* Handle device status changes.
	372	*
	373	* Called from notifier with RTNL held.
	374	*/
	375	static int lapbeth_device_event(struct notifier_block *this,
	376	unsigned long event, void *ptr)
	377	{
	378	struct lapbethdev *lapbeth;
	379	struct net_device *dev = ptr;
	380
c346dca1	381	if (dev_net(dev) != &init_net)
e9dc8653 EB	382	return NOTIFY_DONE;
e9dc8653 EB	383
1da177e4 LT	384	if (!dev_is_ethdev(dev))
	385	return NOTIFY_DONE;
	386
	387	switch (event) {
	388	case NETDEV_UP:
	389	/* New ethernet device -> new LAPB interface */
	390	if (lapbeth_get_x25_dev(dev) == NULL)
	391	lapbeth_new_device(dev);
	392	break;
	393	case NETDEV_DOWN:
	394	/* ethernet device closed -> close LAPB interface */
	395	lapbeth = lapbeth_get_x25_dev(dev);
	396	if (lapbeth)
	397	dev_close(lapbeth->axdev);
	398	break;
	399	case NETDEV_UNREGISTER:
	400	/* ethernet device disappears -> remove LAPB interface */
	401	lapbeth = lapbeth_get_x25_dev(dev);
	402	if (lapbeth)
	403	lapbeth_free_device(lapbeth);
	404	break;
	405	}
	406
	407	return NOTIFY_DONE;
	408	}
	409
	410	/* ------------------------------------------------------------------------ */
	411
7546dd97	412	static struct packet_type lapbeth_packet_type __read_mostly = {
09640e63	413	.type = cpu_to_be16(ETH_P_DEC),
1da177e4 LT	414	.func = lapbeth_rcv,
	415	};
	416
	417	static struct notifier_block lapbeth_dev_notifier = {
	418	.notifier_call = lapbeth_device_event,
	419	};
	420
81b700b1	421	static const char banner[] __initconst =
5ee0d593	422	KERN_INFO "LAPB Ethernet driver version 0.02\n";
1da177e4 LT	423
	424	static int __init lapbeth_init_driver(void)
	425	{
	426	dev_add_pack(&lapbeth_packet_type);
	427
	428	register_netdevice_notifier(&lapbeth_dev_notifier);
	429
	430	printk(banner);
	431
	432	return 0;
	433	}
	434	module_init(lapbeth_init_driver);
	435
	436	static void __exit lapbeth_cleanup_driver(void)
	437	{
	438	struct lapbethdev *lapbeth;
	439	struct list_head entry, tmp;
	440
	441	dev_remove_pack(&lapbeth_packet_type);
	442	unregister_netdevice_notifier(&lapbeth_dev_notifier);
	443
	444	rtnl_lock();
	445	list_for_each_safe(entry, tmp, &lapbeth_devices) {
	446	lapbeth = list_entry(entry, struct lapbethdev, node);
	447
e544ff00	448	dev_put(lapbeth->ethdev);
1da177e4 LT	449	unregister_netdevice(lapbeth->axdev);
	450	}
	451	rtnl_unlock();
	452	}
	453	module_exit(lapbeth_cleanup_driver);
	454
	455	MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
	456	MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
	457	MODULE_LICENSE("GPL");