[deliverable/linux.git] / drivers / net / wan / hdlc.c

/*
 * Generic HDLC support routines for Linux
 *
 * Copyright (C) 1999 - 2008 Krzysztof Halasa <khc@pm.waw.pl>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License
 * as published by the Free Software Foundation.
 *
 * Currently supported:
 *	* raw IP-in-HDLC
 *	* Cisco HDLC
 *	* Frame Relay with ANSI or CCITT LMI (both user and network side)
 *	* PPP
 *	* X.25
 *
 * Use sethdlc utility to set line parameters, protocol and PVCs
 *
 * How does it work:
 * - proto->open(), close(), start(), stop() calls are serialized.
 *   The order is: open, [ start, stop ... ] close ...
 * - proto->start() and stop() are called with spin_lock_irq held.
 */

#include <linux/errno.h>
#include <linux/hdlc.h>
#include <linux/if_arp.h>
#include <linux/inetdevice.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/pkt_sched.h>
#include <linux/poll.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <net/net_namespace.h>


static const char* version = "HDLC support module revision 1.22";

#undef DEBUG_LINK

static struct hdlc_proto *first_proto;

static int hdlc_change_mtu(struct net_device *dev, int new_mtu)
{
	if ((new_mtu < 68) || (new_mtu > HDLC_MAX_MTU))
		return -EINVAL;
	dev->mtu = new_mtu;
	return 0;
}


static struct net_device_stats *hdlc_get_stats(struct net_device *dev)
{
	return &dev->stats;
}


static int hdlc_rcv(struct sk_buff *skb, struct net_device *dev,
		    struct packet_type *p, struct net_device *orig_dev)
{
	struct hdlc_device *hdlc = dev_to_hdlc(dev);

	if (dev_net(dev) != &init_net) {
		kfree_skb(skb);
		return 0;
	}

	BUG_ON(!hdlc->proto->netif_rx);
	return hdlc->proto->netif_rx(skb);
}


static inline void hdlc_proto_start(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	if (hdlc->proto->start)
		hdlc->proto->start(dev);
}


static inline void hdlc_proto_stop(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	if (hdlc->proto->stop)
		hdlc->proto->stop(dev);
}


static int hdlc_device_event(struct notifier_block *this, unsigned long event,
			     void *ptr)
{
	struct net_device *dev = ptr;
	hdlc_device *hdlc;
	unsigned long flags;
	int on;
 
	if (dev_net(dev) != &init_net)
		return NOTIFY_DONE;

	if (dev->get_stats != hdlc_get_stats)
		return NOTIFY_DONE; /* not an HDLC device */

	if (event != NETDEV_CHANGE)
		return NOTIFY_DONE; /* Only interrested in carrier changes */

	on = netif_carrier_ok(dev);

#ifdef DEBUG_LINK
	printk(KERN_DEBUG "%s: hdlc_device_event NETDEV_CHANGE, carrier %i\n",
	       dev->name, on);
#endif

	hdlc = dev_to_hdlc(dev);
	spin_lock_irqsave(&hdlc->state_lock, flags);

	if (hdlc->carrier == on)
		goto carrier_exit; /* no change in DCD line level */

	hdlc->carrier = on;

	if (!hdlc->open)
		goto carrier_exit;

	if (hdlc->carrier) {
		printk(KERN_INFO "%s: Carrier detected\n", dev->name);
		hdlc_proto_start(dev);
	} else {
		printk(KERN_INFO "%s: Carrier lost\n", dev->name);
		hdlc_proto_stop(dev);
	}

carrier_exit:
	spin_unlock_irqrestore(&hdlc->state_lock, flags);
	return NOTIFY_DONE;
}


/* Must be called by hardware driver when HDLC device is being opened */
int hdlc_open(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
#ifdef DEBUG_LINK
	printk(KERN_DEBUG "%s: hdlc_open() carrier %i open %i\n", dev->name,
	       hdlc->carrier, hdlc->open);
#endif

	if (hdlc->proto == NULL)
		return -ENOSYS;	/* no protocol attached */

	if (hdlc->proto->open) {
		int result = hdlc->proto->open(dev);
		if (result)
			return result;
	}

	spin_lock_irq(&hdlc->state_lock);

	if (hdlc->carrier) {
		printk(KERN_INFO "%s: Carrier detected\n", dev->name);
		hdlc_proto_start(dev);
	} else
		printk(KERN_INFO "%s: No carrier\n", dev->name);

	hdlc->open = 1;

	spin_unlock_irq(&hdlc->state_lock);
	return 0;
}


/* Must be called by hardware driver when HDLC device is being closed */
void hdlc_close(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
#ifdef DEBUG_LINK
	printk(KERN_DEBUG "%s: hdlc_close() carrier %i open %i\n", dev->name,
	       hdlc->carrier, hdlc->open);
#endif

	spin_lock_irq(&hdlc->state_lock);

	hdlc->open = 0;
	if (hdlc->carrier)
		hdlc_proto_stop(dev);

	spin_unlock_irq(&hdlc->state_lock);

	if (hdlc->proto->close)
		hdlc->proto->close(dev);
}


int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
	struct hdlc_proto *proto = first_proto;
	int result;

	if (cmd != SIOCWANDEV)
		return -EINVAL;

	if (dev_to_hdlc(dev)->proto) {
		result = dev_to_hdlc(dev)->proto->ioctl(dev, ifr);
		if (result != -EINVAL)
			return result;
	}

	/* Not handled by currently attached protocol (if any) */

	while (proto) {
		if ((result = proto->ioctl(dev, ifr)) != -EINVAL)
			return result;
		proto = proto->next;
	}
	return -EINVAL;
}

static const struct header_ops hdlc_null_ops;

static void hdlc_setup_dev(struct net_device *dev)
{
	/* Re-init all variables changed by HDLC protocol drivers,
	 * including ether_setup() called from hdlc_raw_eth.c.
	 */
	dev->get_stats		 = hdlc_get_stats;
	dev->flags		 = IFF_POINTOPOINT | IFF_NOARP;
	dev->mtu		 = HDLC_MAX_MTU;
	dev->type		 = ARPHRD_RAWHDLC;
	dev->hard_header_len	 = 16;
	dev->addr_len		 = 0;
	dev->header_ops		 = &hdlc_null_ops;

	dev->change_mtu		 = hdlc_change_mtu;
}

static void hdlc_setup(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);

	hdlc_setup_dev(dev);
	hdlc->carrier = 1;
	hdlc->open = 0;
	spin_lock_init(&hdlc->state_lock);
}

struct net_device *alloc_hdlcdev(void *priv)
{
	struct net_device *dev;
	dev = alloc_netdev(sizeof(struct hdlc_device), "hdlc%d", hdlc_setup);
	if (dev)
		dev_to_hdlc(dev)->priv = priv;
	return dev;
}

void unregister_hdlc_device(struct net_device *dev)
{
	rtnl_lock();
	unregister_netdevice(dev);
	detach_hdlc_protocol(dev);
	rtnl_unlock();
}


int attach_hdlc_protocol(struct net_device *dev, struct hdlc_proto *proto,
			 size_t size)
{
	detach_hdlc_protocol(dev);

	if (!try_module_get(proto->module))
		return -ENOSYS;

	if (size)
		if ((dev_to_hdlc(dev)->state = kmalloc(size,
						       GFP_KERNEL)) == NULL) {
			printk(KERN_WARNING "Memory squeeze on"
			       " hdlc_proto_attach()\n");
			module_put(proto->module);
			return -ENOBUFS;
		}
	dev_to_hdlc(dev)->proto = proto;
	return 0;
}


void detach_hdlc_protocol(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);

	if (hdlc->proto) {
		if (hdlc->proto->detach)
			hdlc->proto->detach(dev);
		module_put(hdlc->proto->module);
		hdlc->proto = NULL;
	}
	kfree(hdlc->state);
	hdlc->state = NULL;
	hdlc_setup_dev(dev);
}


void register_hdlc_protocol(struct hdlc_proto *proto)
{
	rtnl_lock();
	proto->next = first_proto;
	first_proto = proto;
	rtnl_unlock();
}


void unregister_hdlc_protocol(struct hdlc_proto *proto)
{
	struct hdlc_proto **p;

	rtnl_lock();
	p = &first_proto;
	while (*p != proto) {
		BUG_ON(!*p);
		p = &((*p)->next);
	}
	*p = proto->next;
	rtnl_unlock();
}


MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
MODULE_DESCRIPTION("HDLC support module");
MODULE_LICENSE("GPL v2");

EXPORT_SYMBOL(hdlc_open);
EXPORT_SYMBOL(hdlc_close);
EXPORT_SYMBOL(hdlc_ioctl);
EXPORT_SYMBOL(alloc_hdlcdev);
EXPORT_SYMBOL(unregister_hdlc_device);
EXPORT_SYMBOL(register_hdlc_protocol);
EXPORT_SYMBOL(unregister_hdlc_protocol);
EXPORT_SYMBOL(attach_hdlc_protocol);
EXPORT_SYMBOL(detach_hdlc_protocol);

static struct packet_type hdlc_packet_type = {
	.type = __constant_htons(ETH_P_HDLC),
	.func = hdlc_rcv,
};


static struct notifier_block hdlc_notifier = {
	.notifier_call = hdlc_device_event,
};


static int __init hdlc_module_init(void)
{
	int result;

	printk(KERN_INFO "%s\n", version);
	if ((result = register_netdevice_notifier(&hdlc_notifier)) != 0)
		return result;
	dev_add_pack(&hdlc_packet_type);
	return 0;
}


static void __exit hdlc_module_exit(void)
{
	dev_remove_pack(&hdlc_packet_type);
	unregister_netdevice_notifier(&hdlc_notifier);
}


module_init(hdlc_module_init);
module_exit(hdlc_module_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Generic HDLC support routines for Linux
	3	*
40d25142	4	* Copyright (C) 1999 - 2008 Krzysztof Halasa <khc@pm.waw.pl>
1da177e4 LT	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of version 2 of the GNU General Public License
	8	* as published by the Free Software Foundation.
	9	*
	10	* Currently supported:
	11	* * raw IP-in-HDLC
	12	* * Cisco HDLC
	13	* * Frame Relay with ANSI or CCITT LMI (both user and network side)
	14	* * PPP
	15	* * X.25
	16	*
	17	* Use sethdlc utility to set line parameters, protocol and PVCs
	18	*
	19	* How does it work:
eb2a2fd9	20	* - proto->open(), close(), start(), stop() calls are serialized.
1da177e4	21	* The order is: open, [ start, stop ... ] close ...
eb2a2fd9	22	* - proto->start() and stop() are called with spin_lock_irq held.
1da177e4 LT	23	*/
1da177e4 LT	24
1da177e4	25	#include <linux/errno.h>
4dfce407	26	#include <linux/hdlc.h>
1da177e4	27	#include <linux/if_arp.h>
4dfce407	28	#include <linux/inetdevice.h>
1da177e4	29	#include <linux/init.h>
4dfce407 KH	30	#include <linux/kernel.h>
	31	#include <linux/module.h>
	32	#include <linux/notifier.h>
1da177e4	33	#include <linux/pkt_sched.h>
4dfce407	34	#include <linux/poll.h>
1da177e4	35	#include <linux/rtnetlink.h>
4dfce407 KH	36	#include <linux/skbuff.h>
4dfce407 KH	37	#include <linux/slab.h>
e730c155	38	#include <net/net_namespace.h>
1da177e4 LT	39
1da177e4 LT	40
40d25142	41	static const char* version = "HDLC support module revision 1.22";
1da177e4 LT	42
	43	#undef DEBUG_LINK
	44
fa701bd2	45	static struct hdlc_proto *first_proto;
1da177e4 LT	46
	47	static int hdlc_change_mtu(struct net_device *dev, int new_mtu)
	48	{
	49	if ((new_mtu < 68) \|\| (new_mtu > HDLC_MAX_MTU))
	50	return -EINVAL;
	51	dev->mtu = new_mtu;
	52	return 0;
	53	}
	54
	55
	56
	57	static struct net_device_stats hdlc_get_stats(struct net_device dev)
	58	{
198191c4	59	return &dev->stats;
1da177e4 LT	60	}
	61
	62
	63
	64	static int hdlc_rcv(struct sk_buff skb, struct net_device dev,
f2ccd8fa	65	struct packet_type p, struct net_device orig_dev)
1da177e4	66	{
40d25142	67	struct hdlc_device *hdlc = dev_to_hdlc(dev);
e730c155	68
c346dca1	69	if (dev_net(dev) != &init_net) {
e730c155 EB	70	kfree_skb(skb);
	71	return 0;
	72	}
	73
40d25142 KH	74	BUG_ON(!hdlc->proto->netif_rx);
40d25142 KH	75	return hdlc->proto->netif_rx(skb);
1da177e4 LT	76	}
	77
	78
	79
c2ce9204	80	static inline void hdlc_proto_start(struct net_device *dev)
1da177e4 LT	81	{
1da177e4 LT	82	hdlc_device *hdlc = dev_to_hdlc(dev);
eb2a2fd9	83	if (hdlc->proto->start)
40d25142	84	hdlc->proto->start(dev);
1da177e4 LT	85	}
	86
	87
	88
c2ce9204	89	static inline void hdlc_proto_stop(struct net_device *dev)
1da177e4 LT	90	{
1da177e4 LT	91	hdlc_device *hdlc = dev_to_hdlc(dev);
eb2a2fd9	92	if (hdlc->proto->stop)
40d25142	93	hdlc->proto->stop(dev);
1da177e4 LT	94	}
	95
	96
	97
c2ce9204 KH	98	static int hdlc_device_event(struct notifier_block *this, unsigned long event,
c2ce9204 KH	99	void *ptr)
1da177e4	100	{
c2ce9204 KH	101	struct net_device *dev = ptr;
c2ce9204 KH	102	hdlc_device *hdlc;
1da177e4	103	unsigned long flags;
c2ce9204 KH	104	int on;
c2ce9204 KH	105
c346dca1	106	if (dev_net(dev) != &init_net)
e9dc8653 EB	107	return NOTIFY_DONE;
e9dc8653 EB	108
c2ce9204 KH	109	if (dev->get_stats != hdlc_get_stats)
c2ce9204 KH	110	return NOTIFY_DONE; /* not an HDLC device */
4dfce407	111
c2ce9204 KH	112	if (event != NETDEV_CHANGE)
	113	return NOTIFY_DONE; /* Only interrested in carrier changes */
	114
	115	on = netif_carrier_ok(dev);
1da177e4 LT	116
1da177e4 LT	117	#ifdef DEBUG_LINK
c2ce9204 KH	118	printk(KERN_DEBUG "%s: hdlc_device_event NETDEV_CHANGE, carrier %i\n",
c2ce9204 KH	119	dev->name, on);
1da177e4 LT	120	#endif
1da177e4 LT	121
c2ce9204	122	hdlc = dev_to_hdlc(dev);
1da177e4 LT	123	spin_lock_irqsave(&hdlc->state_lock, flags);
	124
	125	if (hdlc->carrier == on)
	126	goto carrier_exit; /* no change in DCD line level */
	127
1da177e4 LT	128	hdlc->carrier = on;
	129
	130	if (!hdlc->open)
	131	goto carrier_exit;
	132
b3dd65f9 KH	133	if (hdlc->carrier) {
b3dd65f9 KH	134	printk(KERN_INFO "%s: Carrier detected\n", dev->name);
c2ce9204	135	hdlc_proto_start(dev);
b3dd65f9 KH	136	} else {
b3dd65f9 KH	137	printk(KERN_INFO "%s: Carrier lost\n", dev->name);
c2ce9204	138	hdlc_proto_stop(dev);
b3dd65f9	139	}
1da177e4 LT	140
	141	carrier_exit:
	142	spin_unlock_irqrestore(&hdlc->state_lock, flags);
c2ce9204	143	return NOTIFY_DONE;
1da177e4 LT	144	}
	145
	146
	147
	148	/* Must be called by hardware driver when HDLC device is being opened */
	149	int hdlc_open(struct net_device *dev)
	150	{
	151	hdlc_device *hdlc = dev_to_hdlc(dev);
	152	#ifdef DEBUG_LINK
eb2a2fd9	153	printk(KERN_DEBUG "%s: hdlc_open() carrier %i open %i\n", dev->name,
1da177e4 LT	154	hdlc->carrier, hdlc->open);
	155	#endif
	156
eb2a2fd9	157	if (hdlc->proto == NULL)
1da177e4 LT	158	return -ENOSYS; /* no protocol attached */
1da177e4 LT	159
eb2a2fd9 KH	160	if (hdlc->proto->open) {
eb2a2fd9 KH	161	int result = hdlc->proto->open(dev);
1da177e4 LT	162	if (result)
	163	return result;
	164	}
	165
	166	spin_lock_irq(&hdlc->state_lock);
	167
b3dd65f9 KH	168	if (hdlc->carrier) {
b3dd65f9 KH	169	printk(KERN_INFO "%s: Carrier detected\n", dev->name);
c2ce9204	170	hdlc_proto_start(dev);
b3dd65f9 KH	171	} else
b3dd65f9 KH	172	printk(KERN_INFO "%s: No carrier\n", dev->name);
1da177e4 LT	173
	174	hdlc->open = 1;
	175
	176	spin_unlock_irq(&hdlc->state_lock);
	177	return 0;
	178	}
	179
	180
	181
	182	/* Must be called by hardware driver when HDLC device is being closed */
	183	void hdlc_close(struct net_device *dev)
	184	{
	185	hdlc_device *hdlc = dev_to_hdlc(dev);
	186	#ifdef DEBUG_LINK
eb2a2fd9	187	printk(KERN_DEBUG "%s: hdlc_close() carrier %i open %i\n", dev->name,
1da177e4 LT	188	hdlc->carrier, hdlc->open);
	189	#endif
	190
	191	spin_lock_irq(&hdlc->state_lock);
	192
	193	hdlc->open = 0;
	194	if (hdlc->carrier)
c2ce9204	195	hdlc_proto_stop(dev);
1da177e4 LT	196
	197	spin_unlock_irq(&hdlc->state_lock);
	198
eb2a2fd9 KH	199	if (hdlc->proto->close)
eb2a2fd9 KH	200	hdlc->proto->close(dev);
1da177e4 LT	201	}
	202
	203
	204
1da177e4 LT	205	int hdlc_ioctl(struct net_device dev, struct ifreq ifr, int cmd)
1da177e4 LT	206	{
eb2a2fd9 KH	207	struct hdlc_proto *proto = first_proto;
eb2a2fd9 KH	208	int result;
1da177e4 LT	209
	210	if (cmd != SIOCWANDEV)
	211	return -EINVAL;
	212
eb2a2fd9 KH	213	if (dev_to_hdlc(dev)->proto) {
	214	result = dev_to_hdlc(dev)->proto->ioctl(dev, ifr);
	215	if (result != -EINVAL)
	216	return result;
1da177e4 LT	217	}
1da177e4 LT	218
eb2a2fd9 KH	219	/* Not handled by currently attached protocol (if any) */
	220
	221	while (proto) {
	222	if ((result = proto->ioctl(dev, ifr)) != -EINVAL)
	223	return result;
	224	proto = proto->next;
1da177e4	225	}
eb2a2fd9	226	return -EINVAL;
1da177e4 LT	227	}
1da177e4 LT	228
3b04ddde SH	229	static const struct header_ops hdlc_null_ops;
3b04ddde SH	230
b5284e5a KH	231	static void hdlc_setup_dev(struct net_device *dev)
	232	{
	233	/* Re-init all variables changed by HDLC protocol drivers,
	234	* including ether_setup() called from hdlc_raw_eth.c.
	235	*/
	236	dev->get_stats = hdlc_get_stats;
	237	dev->flags = IFF_POINTOPOINT \| IFF_NOARP;
	238	dev->mtu = HDLC_MAX_MTU;
	239	dev->type = ARPHRD_RAWHDLC;
	240	dev->hard_header_len = 16;
	241	dev->addr_len = 0;
3b04ddde SH	242	dev->header_ops = &hdlc_null_ops;
3b04ddde SH	243
b5284e5a	244	dev->change_mtu = hdlc_change_mtu;
b5284e5a KH	245	}
b5284e5a KH	246
0bf94faf	247	static void hdlc_setup(struct net_device *dev)
1da177e4 LT	248	{
	249	hdlc_device *hdlc = dev_to_hdlc(dev);
	250
b5284e5a	251	hdlc_setup_dev(dev);
1da177e4 LT	252	hdlc->carrier = 1;
	253	hdlc->open = 0;
	254	spin_lock_init(&hdlc->state_lock);
	255	}
	256
	257	struct net_device alloc_hdlcdev(void priv)
	258	{
	259	struct net_device *dev;
40d25142	260	dev = alloc_netdev(sizeof(struct hdlc_device), "hdlc%d", hdlc_setup);
1da177e4 LT	261	if (dev)
	262	dev_to_hdlc(dev)->priv = priv;
	263	return dev;
	264	}
	265
1da177e4 LT	266	void unregister_hdlc_device(struct net_device *dev)
	267	{
	268	rtnl_lock();
1da177e4	269	unregister_netdevice(dev);
eb2a2fd9	270	detach_hdlc_protocol(dev);
1da177e4 LT	271	rtnl_unlock();
	272	}
	273
	274
	275
eb2a2fd9	276	int attach_hdlc_protocol(struct net_device dev, struct hdlc_proto proto,
40d25142	277	size_t size)
eb2a2fd9 KH	278	{
	279	detach_hdlc_protocol(dev);
	280
	281	if (!try_module_get(proto->module))
	282	return -ENOSYS;
	283
	284	if (size)
	285	if ((dev_to_hdlc(dev)->state = kmalloc(size,
	286	GFP_KERNEL)) == NULL) {
	287	printk(KERN_WARNING "Memory squeeze on"
	288	" hdlc_proto_attach()\n");
	289	module_put(proto->module);
	290	return -ENOBUFS;
	291	}
	292	dev_to_hdlc(dev)->proto = proto;
eb2a2fd9 KH	293	return 0;
	294	}
	295
	296
	297	void detach_hdlc_protocol(struct net_device *dev)
	298	{
	299	hdlc_device *hdlc = dev_to_hdlc(dev);
	300
	301	if (hdlc->proto) {
	302	if (hdlc->proto->detach)
	303	hdlc->proto->detach(dev);
	304	module_put(hdlc->proto->module);
	305	hdlc->proto = NULL;
	306	}
	307	kfree(hdlc->state);
	308	hdlc->state = NULL;
b5284e5a	309	hdlc_setup_dev(dev);
eb2a2fd9 KH	310	}
	311
	312
	313	void register_hdlc_protocol(struct hdlc_proto *proto)
	314	{
fa701bd2	315	rtnl_lock();
eb2a2fd9 KH	316	proto->next = first_proto;
eb2a2fd9 KH	317	first_proto = proto;
fa701bd2	318	rtnl_unlock();
eb2a2fd9 KH	319	}
	320
	321
	322	void unregister_hdlc_protocol(struct hdlc_proto *proto)
	323	{
fa701bd2 KH	324	struct hdlc_proto **p;
	325
	326	rtnl_lock();
	327	p = &first_proto;
	328	while (*p != proto) {
	329	BUG_ON(!*p);
eb2a2fd9 KH	330	p = &((*p)->next);
eb2a2fd9 KH	331	}
fa701bd2 KH	332	*p = proto->next;
fa701bd2 KH	333	rtnl_unlock();
eb2a2fd9 KH	334	}
	335
	336
	337
1da177e4 LT	338	MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
	339	MODULE_DESCRIPTION("HDLC support module");
	340	MODULE_LICENSE("GPL v2");
	341
	342	EXPORT_SYMBOL(hdlc_open);
	343	EXPORT_SYMBOL(hdlc_close);
1da177e4 LT	344	EXPORT_SYMBOL(hdlc_ioctl);
1da177e4 LT	345	EXPORT_SYMBOL(alloc_hdlcdev);
1da177e4	346	EXPORT_SYMBOL(unregister_hdlc_device);
eb2a2fd9 KH	347	EXPORT_SYMBOL(register_hdlc_protocol);
	348	EXPORT_SYMBOL(unregister_hdlc_protocol);
	349	EXPORT_SYMBOL(attach_hdlc_protocol);
	350	EXPORT_SYMBOL(detach_hdlc_protocol);
1da177e4 LT	351
	352	static struct packet_type hdlc_packet_type = {
	353	.type = __constant_htons(ETH_P_HDLC),
	354	.func = hdlc_rcv,
	355	};
	356
	357
c2ce9204	358	static struct notifier_block hdlc_notifier = {
4dfce407	359	.notifier_call = hdlc_device_event,
c2ce9204 KH	360	};
	361
	362
1da177e4 LT	363	static int __init hdlc_module_init(void)
1da177e4 LT	364	{
c2ce9204 KH	365	int result;
c2ce9204 KH	366
1da177e4	367	printk(KERN_INFO "%s\n", version);
c2ce9204	368	if ((result = register_netdevice_notifier(&hdlc_notifier)) != 0)
4dfce407 KH	369	return result;
4dfce407 KH	370	dev_add_pack(&hdlc_packet_type);
1da177e4 LT	371	return 0;
	372	}
	373
	374
	375
	376	static void __exit hdlc_module_exit(void)
	377	{
	378	dev_remove_pack(&hdlc_packet_type);
c2ce9204	379	unregister_netdevice_notifier(&hdlc_notifier);
1da177e4 LT	380	}
	381
	382
	383	module_init(hdlc_module_init);
	384	module_exit(hdlc_module_exit);