[deliverable/linux.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/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 int lapbeth_xmit(struct sk_buff *skb, struct net_device *dev)
{
	int err = -ENODEV;

	/*
	 * 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:
		err = 0;
		break;
	case 0x01:
		if ((err = lapb_connect_request(dev)) != LAPB_OK)
			printk(KERN_ERR "lapbeth: lapb_connect_request "
			       "error: %d\n", err);
		goto drop_ok;
	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_ok;
	}

	skb_pull(skb, 1);

	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
		printk(KERN_ERR "lapbeth: lapb_data_request error - %d\n", err);
		err = -ENOMEM;
		goto drop;
	}
	err = 0;
out:
	return err;
drop_ok:
	err = 0;
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 void lapbeth_setup(struct net_device *dev)
{
	dev->hard_start_xmit = lapbeth_xmit;
	dev->open	     = lapbeth_open;
	dev->stop	     = lapbeth_close;
	dev->destructor	     = free_netdev;
	dev->set_mac_address = lapbeth_set_mac_address;
	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>
	27	#include <linux/kernel.h>
	28	#include <linux/string.h>
	29	#include <linux/net.h>
	30	#include <linux/inet.h>
	31	#include <linux/netdevice.h>
	32	#include <linux/if_arp.h>
	33	#include <linux/skbuff.h>
	34	#include <net/sock.h>
	35	#include <asm/system.h>
	36	#include <asm/uaccess.h>
	37	#include <linux/mm.h>
	38	#include <linux/interrupt.h>
	39	#include <linux/notifier.h>
	40	#include <linux/stat.h>
	41	#include <linux/netfilter.h>
	42	#include <linux/module.h>
	43	#include <linux/lapb.h>
	44	#include <linux/init.h>
	45
	46	#include <net/x25device.h>
	47
	48	static char bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
	49
	50	/* If this number is made larger, check that the temporary string buffer
	51	* in lapbeth_new_device is large enough to store the probe device name.*/
	52	#define MAXLAPBDEV 100
	53
	54	struct lapbethdev {
	55	struct list_head node;
	56	struct net_device ethdev; / link to ethernet device */
	57	struct net_device axdev; / lapbeth device (lapb#) */
1da177e4 LT	58	};
1da177e4 LT	59
293a3839	60	static LIST_HEAD(lapbeth_devices);
1da177e4 LT	61
	62	/* ------------------------------------------------------------------------ */
	63
	64	/*
	65	* Get the LAPB device for the ethernet device
	66	*/
	67	static struct lapbethdev lapbeth_get_x25_dev(struct net_device dev)
	68	{
	69	struct lapbethdev *lapbeth;
	70
	71	list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
	72	if (lapbeth->ethdev == dev)
	73	return lapbeth;
	74	}
	75	return NULL;
	76	}
	77
	78	static __inline__ int dev_is_ethdev(struct net_device *dev)
	79	{
	80	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
	81	}
	82
	83	/* ------------------------------------------------------------------------ */
	84
	85	/*
	86	* Receive a LAPB frame via an ethernet interface.
	87	*/
f2ccd8fa	88	static int lapbeth_rcv(struct sk_buff skb, struct net_device dev, struct packet_type ptype, struct net_device orig_dev)
1da177e4 LT	89	{
	90	int len, err;
	91	struct lapbethdev *lapbeth;
	92
c346dca1	93	if (dev_net(dev) != &init_net)
e730c155 EB	94	goto drop;
e730c155 EB	95
1da177e4 LT	96	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
	97	return NET_RX_DROP;
	98
	99	if (!pskb_may_pull(skb, 2))
	100	goto drop;
	101
	102	rcu_read_lock();
	103	lapbeth = lapbeth_get_x25_dev(dev);
	104	if (!lapbeth)
	105	goto drop_unlock;
	106	if (!netif_running(lapbeth->axdev))
	107	goto drop_unlock;
	108
1da177e4	109	len = skb->data[0] + skb->data[1] * 256;
ea2ebaf8 SH	110	dev->stats.rx_packets++;
ea2ebaf8 SH	111	dev->stats.rx_bytes += len;
1da177e4 LT	112
	113	skb_pull(skb, 2); /* Remove the length bytes */
	114	skb_trim(skb, len); /* Set the length of the data */
	115
	116	if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
	117	printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
	118	goto drop_unlock;
	119	}
	120	out:
	121	rcu_read_unlock();
	122	return 0;
	123	drop_unlock:
	124	kfree_skb(skb);
	125	goto out;
	126	drop:
	127	kfree_skb(skb);
	128	return 0;
	129	}
	130
	131	static int lapbeth_data_indication(struct net_device dev, struct sk_buff skb)
	132	{
	133	unsigned char *ptr;
	134
	135	skb_push(skb, 1);
	136
	137	if (skb_cow(skb, 1))
	138	return NET_RX_DROP;
	139
	140	ptr = skb->data;
	141	*ptr = 0x00;
	142
	143	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	144	return netif_rx(skb);
	145	}
	146
	147	/*
	148	* Send a LAPB frame via an ethernet interface
	149	*/
	150	static int lapbeth_xmit(struct sk_buff skb, struct net_device dev)
	151	{
	152	int err = -ENODEV;
	153
	154	/*
	155	* Just to be really sure not to send anything if the interface
	156	* is down, the ethernet device may have gone.
	157	*/
	158	if (!netif_running(dev)) {
	159	goto drop;
	160	}
	161
	162	switch (skb->data[0]) {
	163	case 0x00:
	164	err = 0;
	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);
	170	goto drop_ok;
	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:
	177	goto drop_ok;
	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);
	184	err = -ENOMEM;
	185	goto drop;
	186	}
	187	err = 0;
	188	out:
	189	return err;
	190	drop_ok:
	191	err = 0;
	192	drop:
	193	kfree_skb(skb);
	194	goto out;
	195	}
	196
	197	static void lapbeth_data_transmit(struct net_device ndev, struct sk_buff skb)
	198	{
	199	struct lapbethdev *lapbeth = netdev_priv(ndev);
	200	unsigned char *ptr;
	201	struct net_device *dev;
	202	int size = skb->len;
	203
	204	skb->protocol = htons(ETH_P_X25);
	205
	206	ptr = skb_push(skb, 2);
	207
208	*ptr++ = size % 256;
209	*ptr++ = size / 256;
210
ea2ebaf8 SH	211	ndev->stats.tx_packets++;
ea2ebaf8 SH	212	ndev->stats.tx_bytes += size;
1da177e4 LT	213
	214	skb->dev = dev = lapbeth->ethdev;
	215
0c4e8581	216	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
1da177e4 LT	217
	218	dev_queue_xmit(skb);
	219	}
	220
	221	static void lapbeth_connected(struct net_device *dev, int reason)
	222	{
	223	unsigned char *ptr;
	224	struct sk_buff *skb = dev_alloc_skb(1);
	225
	226	if (!skb) {
	227	printk(KERN_ERR "lapbeth: out of memory\n");
	228	return;
	229	}
	230
	231	ptr = skb_put(skb, 1);
	232	*ptr = 0x01;
	233
	234	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	235	netif_rx(skb);
	236	}
	237
	238	static void lapbeth_disconnected(struct net_device *dev, int reason)
	239	{
	240	unsigned char *ptr;
	241	struct sk_buff *skb = dev_alloc_skb(1);
	242
	243	if (!skb) {
	244	printk(KERN_ERR "lapbeth: out of memory\n");
	245	return;
	246	}
	247
	248	ptr = skb_put(skb, 1);
	249	*ptr = 0x02;
	250
	251	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	252	netif_rx(skb);
	253	}
	254
1da177e4 LT	255	/*
	256	* Set AX.25 callsign
	257	*/
	258	static int lapbeth_set_mac_address(struct net_device dev, void addr)
	259	{
	260	struct sockaddr *sa = addr;
	261	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
	262	return 0;
	263	}
	264
	265
	266	static struct lapb_register_struct lapbeth_callbacks = {
	267	.connect_confirmation = lapbeth_connected,
	268	.connect_indication = lapbeth_connected,
	269	.disconnect_confirmation = lapbeth_disconnected,
	270	.disconnect_indication = lapbeth_disconnected,
	271	.data_indication = lapbeth_data_indication,
	272	.data_transmit = lapbeth_data_transmit,
	273
	274	};
	275
	276	/*
	277	* open/close a device
	278	*/
	279	static int lapbeth_open(struct net_device *dev)
	280	{
	281	int err;
	282
	283	if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
	284	printk(KERN_ERR "lapbeth: lapb_register error - %d\n", err);
	285	return -ENODEV;
	286	}
	287
	288	netif_start_queue(dev);
	289	return 0;
	290	}
	291
	292	static int lapbeth_close(struct net_device *dev)
	293	{
	294	int err;
	295
	296	netif_stop_queue(dev);
	297
	298	if ((err = lapb_unregister(dev)) != LAPB_OK)
	299	printk(KERN_ERR "lapbeth: lapb_unregister error - %d\n", err);
	300
	301	return 0;
	302	}
	303
	304	/* ------------------------------------------------------------------------ */
	305
	306	static void lapbeth_setup(struct net_device *dev)
	307	{
	308	dev->hard_start_xmit = lapbeth_xmit;
	309	dev->open = lapbeth_open;
	310	dev->stop = lapbeth_close;
	311	dev->destructor = free_netdev;
	312	dev->set_mac_address = lapbeth_set_mac_address;
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");