[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 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>
	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	*/
d71a6749 SH	150	static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
d71a6749 SH	151	struct net_device *dev)
1da177e4	152	{
d77eeb70	153	int err;
1da177e4 LT	154
	155	/*
	156	* Just to be really sure not to send anything if the interface
	157	* is down, the ethernet device may have gone.
	158	*/
d77eeb70	159	if (!netif_running(dev))
1da177e4	160	goto drop;
1da177e4 LT	161
	162	switch (skb->data[0]) {
	163	case 0x00:
1da177e4 LT	164	break;
	165	case 0x01:
	166	if ((err = lapb_connect_request(dev)) != LAPB_OK)
	167	printk(KERN_ERR "lapbeth: lapb_connect_request "
	168	"error: %d\n", err);
d77eeb70	169	goto drop;
1da177e4 LT	170	case 0x02:
	171	if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
	172	printk(KERN_ERR "lapbeth: lapb_disconnect_request "
	173	"err: %d\n", err);
	174	/* Fall thru */
	175	default:
d77eeb70	176	goto drop;
1da177e4 LT	177	}
	178
	179	skb_pull(skb, 1);
	180
	181	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
	182	printk(KERN_ERR "lapbeth: lapb_data_request error - %d\n", err);
1da177e4 LT	183	goto drop;
1da177e4 LT	184	}
1da177e4	185	out:
d77eeb70	186	return NETDEV_TX_OK;
1da177e4 LT	187	drop:
	188	kfree_skb(skb);
	189	goto out;
	190	}
	191
	192	static void lapbeth_data_transmit(struct net_device ndev, struct sk_buff skb)
	193	{
	194	struct lapbethdev *lapbeth = netdev_priv(ndev);
	195	unsigned char *ptr;
	196	struct net_device *dev;
	197	int size = skb->len;
	198
	199	skb->protocol = htons(ETH_P_X25);
	200
	201	ptr = skb_push(skb, 2);
	202
	203	*ptr++ = size % 256;
	204	*ptr++ = size / 256;
	205
ea2ebaf8 SH	206	ndev->stats.tx_packets++;
ea2ebaf8 SH	207	ndev->stats.tx_bytes += size;
1da177e4 LT	208
	209	skb->dev = dev = lapbeth->ethdev;
	210
0c4e8581	211	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
1da177e4 LT	212
	213	dev_queue_xmit(skb);
	214	}
	215
	216	static void lapbeth_connected(struct net_device *dev, int reason)
	217	{
	218	unsigned char *ptr;
	219	struct sk_buff *skb = dev_alloc_skb(1);
	220
	221	if (!skb) {
	222	printk(KERN_ERR "lapbeth: out of memory\n");
	223	return;
	224	}
	225
	226	ptr = skb_put(skb, 1);
	227	*ptr = 0x01;
	228
	229	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	230	netif_rx(skb);
	231	}
	232
	233	static void lapbeth_disconnected(struct net_device *dev, int reason)
	234	{
	235	unsigned char *ptr;
	236	struct sk_buff *skb = dev_alloc_skb(1);
	237
	238	if (!skb) {
	239	printk(KERN_ERR "lapbeth: out of memory\n");
	240	return;
	241	}
	242
	243	ptr = skb_put(skb, 1);
	244	*ptr = 0x02;
	245
	246	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	247	netif_rx(skb);
	248	}
	249
1da177e4 LT	250	/*
	251	* Set AX.25 callsign
	252	*/
	253	static int lapbeth_set_mac_address(struct net_device dev, void addr)
	254	{
	255	struct sockaddr *sa = addr;
	256	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
	257	return 0;
	258	}
	259
	260
	261	static struct lapb_register_struct lapbeth_callbacks = {
	262	.connect_confirmation = lapbeth_connected,
	263	.connect_indication = lapbeth_connected,
	264	.disconnect_confirmation = lapbeth_disconnected,
	265	.disconnect_indication = lapbeth_disconnected,
	266	.data_indication = lapbeth_data_indication,
	267	.data_transmit = lapbeth_data_transmit,
	268
	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	printk(KERN_ERR "lapbeth: 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	printk(KERN_ERR "lapbeth: lapb_unregister error - %d\n", err);
	295
	296	return 0;
	297	}
	298
	299	/* ------------------------------------------------------------------------ */
	300
39549b1e SH	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
1da177e4 LT	308	static void lapbeth_setup(struct net_device *dev)
1da177e4 LT	309	{
39549b1e	310	dev->netdev_ops = &lapbeth_netdev_ops;
1da177e4	311	dev->destructor = free_netdev;
1da177e4 LT	312	dev->type = ARPHRD_X25;
	313	dev->hard_header_len = 3;
	314	dev->mtu = 1000;
	315	dev->addr_len = 0;
1da177e4 LT	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 = dev_alloc_name(ndev, ndev->name);
	341	if (rc < 0)
	342	goto fail;
	343
	344	rc = -EIO;
	345	if (register_netdevice(ndev))
	346	goto fail;
	347
	348	list_add_rcu(&lapbeth->node, &lapbeth_devices);
	349	rc = 0;
	350	out:
	351	return rc;
	352	fail:
	353	dev_put(dev);
	354	free_netdev(ndev);
	355	kfree(lapbeth);
	356	goto out;
	357	}
	358
	359	/*
	360	* Free a lapb network device.
	361	*/
	362	static void lapbeth_free_device(struct lapbethdev *lapbeth)
	363	{
	364	dev_put(lapbeth->ethdev);
	365	list_del_rcu(&lapbeth->node);
	366	unregister_netdevice(lapbeth->axdev);
	367	}
	368
	369	/*
	370	* Handle device status changes.
	371	*
	372	* Called from notifier with RTNL held.
	373	*/
	374	static int lapbeth_device_event(struct notifier_block *this,
	375	unsigned long event, void *ptr)
	376	{
	377	struct lapbethdev *lapbeth;
	378	struct net_device *dev = ptr;
	379
c346dca1	380	if (dev_net(dev) != &init_net)
e9dc8653 EB	381	return NOTIFY_DONE;
e9dc8653 EB	382
1da177e4 LT	383	if (!dev_is_ethdev(dev))
	384	return NOTIFY_DONE;
	385
	386	switch (event) {
	387	case NETDEV_UP:
	388	/* New ethernet device -> new LAPB interface */
	389	if (lapbeth_get_x25_dev(dev) == NULL)
	390	lapbeth_new_device(dev);
	391	break;
	392	case NETDEV_DOWN:
	393	/* ethernet device closed -> close LAPB interface */
	394	lapbeth = lapbeth_get_x25_dev(dev);
	395	if (lapbeth)
	396	dev_close(lapbeth->axdev);
	397	break;
	398	case NETDEV_UNREGISTER:
	399	/* ethernet device disappears -> remove LAPB interface */
	400	lapbeth = lapbeth_get_x25_dev(dev);
	401	if (lapbeth)
	402	lapbeth_free_device(lapbeth);
	403	break;
	404	}
	405
	406	return NOTIFY_DONE;
	407	}
	408
	409	/* ------------------------------------------------------------------------ */
	410
7546dd97	411	static struct packet_type lapbeth_packet_type __read_mostly = {
09640e63	412	.type = cpu_to_be16(ETH_P_DEC),
1da177e4 LT	413	.func = lapbeth_rcv,
	414	};
	415
	416	static struct notifier_block lapbeth_dev_notifier = {
	417	.notifier_call = lapbeth_device_event,
	418	};
	419
81b700b1	420	static const char banner[] __initconst =
5ee0d593	421	KERN_INFO "LAPB Ethernet driver version 0.02\n";
1da177e4 LT	422
	423	static int __init lapbeth_init_driver(void)
	424	{
	425	dev_add_pack(&lapbeth_packet_type);
	426
	427	register_netdevice_notifier(&lapbeth_dev_notifier);
	428
	429	printk(banner);
	430
	431	return 0;
	432	}
	433	module_init(lapbeth_init_driver);
	434
	435	static void __exit lapbeth_cleanup_driver(void)
	436	{
	437	struct lapbethdev *lapbeth;
	438	struct list_head entry, tmp;
	439
	440	dev_remove_pack(&lapbeth_packet_type);
	441	unregister_netdevice_notifier(&lapbeth_dev_notifier);
	442
	443	rtnl_lock();
	444	list_for_each_safe(entry, tmp, &lapbeth_devices) {
	445	lapbeth = list_entry(entry, struct lapbethdev, node);
	446
e544ff00	447	dev_put(lapbeth->ethdev);
1da177e4 LT	448	unregister_netdevice(lapbeth->axdev);
	449	}
	450	rtnl_unlock();
	451	}
	452	module_exit(lapbeth_cleanup_driver);
	453
	454	MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
	455	MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
	456	MODULE_LICENSE("GPL");