/*

   * lec.c: Lan Emulation driver

   *

   * Marko Kiiskila <mkiiskila@yahoo.com>

   */

  #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__

  #include <linux/slab.h>

  #include <linux/kernel.h>
  #include <linux/bitops.h>

  #include <linux/capability.h>

  
  /* We are ethernet device */
  #include <linux/if_ether.h>
  #include <linux/netdevice.h>
  #include <linux/etherdevice.h>
  #include <net/sock.h>
  #include <linux/skbuff.h>
  #include <linux/ip.h>
  #include <asm/byteorder.h>

  #include <linux/uaccess.h>

  #include <net/arp.h>
  #include <net/dst.h>
  #include <linux/proc_fs.h>
  #include <linux/spinlock.h>

  #include <linux/seq_file.h>
  
  /* TokenRing if needed */
  #ifdef CONFIG_TR
  #include <linux/trdevice.h>
  #endif
  
  /* And atm device */
  #include <linux/atmdev.h>
  #include <linux/atmlec.h>
  
  /* Proxy LEC knows about bridging */
  #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)

  #include "../bridge/br_private.h"

  static unsigned char bridge_ula_lec[] = { 0x01, 0x80, 0xc2, 0x00, 0x00 };

  #endif
  
  /* Modular too */
  #include <linux/module.h>
  #include <linux/init.h>
  
  #include "lec.h"
  #include "lec_arpc.h"
  #include "resources.h"

  #define DUMP_PACKETS 0		/*
  				 * 0 = None,
  				 * 1 = 30 first bytes
  				 * 2 = Whole packet
  				 */

  #define LEC_UNRES_QUE_LEN 8	/*
  				 * number of tx packets to queue for a
  				 * single destination while waiting for SVC
  				 */

  
  static int lec_open(struct net_device *dev);

  static netdev_tx_t lec_start_xmit(struct sk_buff *skb,
  				  struct net_device *dev);

  static int lec_close(struct net_device *dev);

  static struct lec_arp_table *lec_arp_find(struct lec_priv *priv,

  					  const unsigned char *mac_addr);

  static int lec_arp_remove(struct lec_priv *priv,

  			  struct lec_arp_table *to_remove);

  /* LANE2 functions */

  static void lane2_associate_ind(struct net_device *dev, const u8 *mac_address,
  				const u8 *tlvs, u32 sizeoftlvs);
  static int lane2_resolve(struct net_device *dev, const u8 *dst_mac, int force,

  			 u8 **tlvs, u32 *sizeoftlvs);

  static int lane2_associate_req(struct net_device *dev, const u8 *lan_dst,
  			       const u8 *tlvs, u32 sizeoftlvs);

  static int lec_addr_delete(struct lec_priv *priv, const unsigned char *atm_addr,

  			   unsigned long permanent);
  static void lec_arp_check_empties(struct lec_priv *priv,
  				  struct atm_vcc *vcc, struct sk_buff *skb);
  static void lec_arp_destroy(struct lec_priv *priv);
  static void lec_arp_init(struct lec_priv *priv);

  static struct atm_vcc *lec_arp_resolve(struct lec_priv *priv,

  				       const unsigned char *mac_to_find,

  				       int is_rdesc,
  				       struct lec_arp_table **ret_entry);

  static void lec_arp_update(struct lec_priv *priv, const unsigned char *mac_addr,

  			   const unsigned char *atm_addr,
  			   unsigned long remoteflag,

  			   unsigned int targetless_le_arp);
  static void lec_flush_complete(struct lec_priv *priv, unsigned long tran_id);
  static int lec_mcast_make(struct lec_priv *priv, struct atm_vcc *vcc);
  static void lec_set_flush_tran_id(struct lec_priv *priv,

  				  const unsigned char *atm_addr,

  				  unsigned long tran_id);

  static void lec_vcc_added(struct lec_priv *priv,
  			  const struct atmlec_ioc *ioc_data,

  			  struct atm_vcc *vcc,

  			  void (*old_push)(struct atm_vcc *vcc,
  					   struct sk_buff *skb));

  static void lec_vcc_close(struct lec_priv *priv, struct atm_vcc *vcc);

  /* must be done under lec_arp_lock */
  static inline void lec_arp_hold(struct lec_arp_table *entry)
  {
  	atomic_inc(&entry->usage);
  }
  
  static inline void lec_arp_put(struct lec_arp_table *entry)
  {
  	if (atomic_dec_and_test(&entry->usage))
  		kfree(entry);
  }

  static struct lane2_ops lane2_ops = {

  	lane2_resolve,		/* resolve,             spec 3.1.3 */
  	lane2_associate_req,	/* associate_req,       spec 3.1.4 */
  	NULL			/* associate indicator, spec 3.1.5 */

  };

  static unsigned char bus_mac[ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };

  
  /* Device structures */
  static struct net_device *dev_lec[MAX_LEC_ITF];
  
  #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
  static void lec_handle_bridge(struct sk_buff *skb, struct net_device *dev)
  {

  	char *buff;
  	struct lec_priv *priv;
  
  	/*
  	 * Check if this is a BPDU. If so, ask zeppelin to send
  	 * LE_TOPOLOGY_REQUEST with the same value of Topology Change bit
  	 * as the Config BPDU has
  	 */

  	buff = skb->data + skb->dev->hard_header_len;
  	if (*buff++ == 0x42 && *buff++ == 0x42 && *buff++ == 0x03) {

  		struct sock *sk;

  		struct sk_buff *skb2;
  		struct atmlec_msg *mesg;
  
  		skb2 = alloc_skb(sizeof(struct atmlec_msg), GFP_ATOMIC);
  		if (skb2 == NULL)
  			return;
  		skb2->len = sizeof(struct atmlec_msg);
  		mesg = (struct atmlec_msg *)skb2->data;
  		mesg->type = l_topology_change;
  		buff += 4;

  		mesg->content.normal.flag = *buff & 0x01;
  					/* 0x01 is topology change */

  		priv = netdev_priv(dev);

  		atm_force_charge(priv->lecd, skb2->truesize);

  		sk = sk_atm(priv->lecd);

  		skb_queue_tail(&sk->sk_receive_queue, skb2);
  		sk->sk_data_ready(sk, skb2->len);
  	}

  }
  #endif /* defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE) */
  
  /*
   * Modelled after tr_type_trans
   * All multicast and ARE or STE frames go to BUS.
   * Non source routed frames go by destination address.
   * Last hop source routed frames go by destination address.
   * Not last hop source routed frames go by _next_ route descriptor.
   * Returns pointer to destination MAC address or fills in rdesc
   * and returns NULL.
   */
  #ifdef CONFIG_TR
  static unsigned char *get_tr_dst(unsigned char *packet, unsigned char *rdesc)
  {

  	struct trh_hdr *trh;

  	unsigned int riflen, num_rdsc;

  
  	trh = (struct trh_hdr *)packet;
  	if (trh->daddr[0] & (uint8_t) 0x80)
  		return bus_mac;	/* multicast */
  
  	if (trh->saddr[0] & TR_RII) {
  		riflen = (ntohs(trh->rcf) & TR_RCF_LEN_MASK) >> 8;
  		if ((ntohs(trh->rcf) >> 13) != 0)
  			return bus_mac;	/* ARE or STE */
  	} else
  		return trh->daddr;	/* not source routed */
  
  	if (riflen < 6)
  		return trh->daddr;	/* last hop, source routed */
  
  	/* riflen is 6 or more, packet has more than one route descriptor */
  	num_rdsc = (riflen / 2) - 1;
  	memset(rdesc, 0, ETH_ALEN);
  	/* offset 4 comes from LAN destination field in LE control frames */
  	if (trh->rcf & htons((uint16_t) TR_RCF_DIR_BIT))

  		memcpy(&rdesc[4], &trh->rseg[num_rdsc - 2], sizeof(__be16));

  	else {

  		memcpy(&rdesc[4], &trh->rseg[1], sizeof(__be16));

  		rdesc[5] = ((ntohs(trh->rseg[0]) & 0x000f) | (rdesc[5] & 0xf0));
  	}
  
  	return NULL;

  }
  #endif /* CONFIG_TR */
  
  /*
   * Open/initialize the netdevice. This is called (in the current kernel)
   * sometime after booting when the 'ifconfig' program is run.
   *
   * This routine should set everything up anew at each open, even
   * registers that "should" only need to be set once at boot, so that
   * there is non-reboot way to recover if something goes wrong.
   */

  static int lec_open(struct net_device *dev)

  {

  	netif_start_queue(dev);

  
  	return 0;

  }

  static void
  lec_send(struct atm_vcc *vcc, struct sk_buff *skb)

  {

  	struct net_device *dev = skb->dev;

  	ATM_SKB(skb)->vcc = vcc;
  	ATM_SKB(skb)->atm_options = vcc->atm_options;
  
  	atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
  	if (vcc->send(vcc, skb) < 0) {

  		dev->stats.tx_dropped++;

  		return;
  	}

  	dev->stats.tx_packets++;
  	dev->stats.tx_bytes += skb->len;

  }

  static void lec_tx_timeout(struct net_device *dev)

  {

  	pr_info("%s
  ", dev->name);

  	dev->trans_start = jiffies;
  	netif_wake_queue(dev);
  }

  static netdev_tx_t lec_start_xmit(struct sk_buff *skb,
  				  struct net_device *dev)

  {

  	struct sk_buff *skb2;

  	struct lec_priv *priv = netdev_priv(dev);

  	struct lecdatahdr_8023 *lec_h;
  	struct atm_vcc *vcc;

  	struct lec_arp_table *entry;

  	unsigned char *dst;

  	int min_frame_size;
  #ifdef CONFIG_TR

  	unsigned char rdesc[ETH_ALEN];	/* Token Ring route descriptor */

  #endif

  	int is_rdesc;

  	pr_debug("called
  ");

  	if (!priv->lecd) {

  		pr_info("%s:No lecd attached
  ", dev->name);

  		dev->stats.tx_errors++;

  		netif_stop_queue(dev);

  		kfree_skb(skb);
  		return NETDEV_TX_OK;

  	}

  	pr_debug("skbuff head:%lx data:%lx tail:%lx end:%lx
  ",

  		 (long)skb->head, (long)skb->data, (long)skb_tail_pointer(skb),
  		 (long)skb_end_pointer(skb));

  #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)

  	if (memcmp(skb->data, bridge_ula_lec, sizeof(bridge_ula_lec)) == 0)
  		lec_handle_bridge(skb, dev);

  #endif

  	/* Make sure we have room for lec_id */
  	if (skb_headroom(skb) < 2) {

  		pr_debug("reallocating skb
  ");

  		skb2 = skb_realloc_headroom(skb, LEC_HEADER_LEN);
  		kfree_skb(skb);
  		if (skb2 == NULL)

  			return NETDEV_TX_OK;

  		skb = skb2;
  	}
  	skb_push(skb, 2);

  	/* Put le header to place, works for TokenRing too */
  	lec_h = (struct lecdatahdr_8023 *)skb->data;
  	lec_h->le_header = htons(priv->lecid);

  
  #ifdef CONFIG_TR

  	/*
  	 * Ugly. Use this to realign Token Ring packets for
  	 * e.g. PCA-200E driver.
  	 */
  	if (priv->is_trdev) {
  		skb2 = skb_realloc_headroom(skb, LEC_HEADER_LEN);
  		kfree_skb(skb);
  		if (skb2 == NULL)

  			return NETDEV_TX_OK;

  		skb = skb2;
  	}

  #endif

  #if DUMP_PACKETS >= 2

  #define MAX_DUMP_SKB 99

  #elif DUMP_PACKETS >= 1

  #define MAX_DUMP_SKB 30
  #endif
  #if DUMP_PACKETS >= 1
  	printk(KERN_DEBUG "%s: send datalen:%ld lecid:%4.4x
  ",
  	       dev->name, skb->len, priv->lecid);
  	print_hex_dump(KERN_DEBUG, "", DUMP_OFFSET, 16, 1,
  		       skb->data, min(skb->len, MAX_DUMP_SKB), true);

  #endif /* DUMP_PACKETS >= 1 */

  	/* Minimum ethernet-frame size */

  #ifdef CONFIG_TR

  	if (priv->is_trdev)
  		min_frame_size = LEC_MINIMUM_8025_SIZE;

  	else
  #endif

  		min_frame_size = LEC_MINIMUM_8023_SIZE;
  	if (skb->len < min_frame_size) {
  		if ((skb->len + skb_tailroom(skb)) < min_frame_size) {
  			skb2 = skb_copy_expand(skb, 0,
  					       min_frame_size - skb->truesize,
  					       GFP_ATOMIC);
  			dev_kfree_skb(skb);
  			if (skb2 == NULL) {

  				dev->stats.tx_dropped++;

  				return NETDEV_TX_OK;

  			}
  			skb = skb2;
  		}

  		skb_put(skb, min_frame_size - skb->len);

  	}
  
  	/* Send to right vcc */
  	is_rdesc = 0;
  	dst = lec_h->h_dest;

  #ifdef CONFIG_TR

  	if (priv->is_trdev) {
  		dst = get_tr_dst(skb->data + 2, rdesc);
  		if (dst == NULL) {
  			dst = rdesc;
  			is_rdesc = 1;
  		}
  	}

  #endif

  	entry = NULL;
  	vcc = lec_arp_resolve(priv, dst, is_rdesc, &entry);

  	pr_debug("%s:vcc:%p vcc_flags:%lx, entry:%p
  ",
  		 dev->name, vcc, vcc ? vcc->flags : 0, entry);

  	if (!vcc || !test_bit(ATM_VF_READY, &vcc->flags)) {
  		if (entry && (entry->tx_wait.qlen < LEC_UNRES_QUE_LEN)) {

  			pr_debug("%s:queuing packet, MAC address %pM
  ",
  				 dev->name, lec_h->h_dest);

  			skb_queue_tail(&entry->tx_wait, skb);
  		} else {

  			pr_debug("%s:tx queue full or no arp entry, dropping, MAC address: %pM
  ",
  				 dev->name, lec_h->h_dest);

  			dev->stats.tx_dropped++;

  			dev_kfree_skb(skb);
  		}

  		goto out;

  	}
  #if DUMP_PACKETS > 0

  	printk(KERN_DEBUG "%s:sending to vpi:%d vci:%d
  ",
  	       dev->name, vcc->vpi, vcc->vci);

  #endif /* DUMP_PACKETS > 0 */

  
  	while (entry && (skb2 = skb_dequeue(&entry->tx_wait))) {

  		pr_debug("emptying tx queue, MAC address %pM
  ", lec_h->h_dest);

  		lec_send(vcc, skb2);

  	}

  	lec_send(vcc, skb);

  
  	if (!atm_may_send(vcc, 0)) {
  		struct lec_vcc_priv *vpriv = LEC_VCC_PRIV(vcc);
  
  		vpriv->xoff = 1;
  		netif_stop_queue(dev);
  
  		/*
  		 * vcc->pop() might have occurred in between, making
  		 * the vcc usuable again.  Since xmit is serialized,
  		 * this is the only situation we have to re-test.
  		 */
  
  		if (atm_may_send(vcc, 0))
  			netif_wake_queue(dev);
  	}

  out:
  	if (entry)
  		lec_arp_put(entry);

  	dev->trans_start = jiffies;

  	return NETDEV_TX_OK;

  }
  
  /* The inverse routine to net_open(). */

  static int lec_close(struct net_device *dev)

  {

  	netif_stop_queue(dev);
  	return 0;

  }

  static int lec_atm_send(struct atm_vcc *vcc, struct sk_buff *skb)

  {
  	unsigned long flags;

  	struct net_device *dev = (struct net_device *)vcc->proto_data;

  	struct lec_priv *priv = netdev_priv(dev);

  	struct atmlec_msg *mesg;
  	struct lec_arp_table *entry;
  	int i;
  	char *tmp;		/* FIXME */

  
  	atomic_sub(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);

  	mesg = (struct atmlec_msg *)skb->data;
  	tmp = skb->data;
  	tmp += sizeof(struct atmlec_msg);

  	pr_debug("%s: msg from zeppelin:%d
  ", dev->name, mesg->type);

  	switch (mesg->type) {
  	case l_set_mac_addr:

  		for (i = 0; i < 6; i++)

  			dev->dev_addr[i] = mesg->content.normal.mac_addr[i];

  		break;
  	case l_del_mac_addr:

  		for (i = 0; i < 6; i++)

  			dev->dev_addr[i] = 0;

  		break;
  	case l_addr_delete:
  		lec_addr_delete(priv, mesg->content.normal.atm_addr,
  				mesg->content.normal.flag);
  		break;
  	case l_topology_change:
  		priv->topology_change = mesg->content.normal.flag;
  		break;
  	case l_flush_complete:
  		lec_flush_complete(priv, mesg->content.normal.flag);
  		break;
  	case l_narp_req:	/* LANE2: see 7.1.35 in the lane2 spec */

  		spin_lock_irqsave(&priv->lec_arp_lock, flags);

  		entry = lec_arp_find(priv, mesg->content.normal.mac_addr);
  		lec_arp_remove(priv, entry);

  		spin_unlock_irqrestore(&priv->lec_arp_lock, flags);

  		if (mesg->content.normal.no_source_le_narp)
  			break;
  		/* FALL THROUGH */
  	case l_arp_update:
  		lec_arp_update(priv, mesg->content.normal.mac_addr,
  			       mesg->content.normal.atm_addr,
  			       mesg->content.normal.flag,
  			       mesg->content.normal.targetless_le_arp);

  		pr_debug("in l_arp_update
  ");

  		if (mesg->sizeoftlvs != 0) {	/* LANE2 3.1.5 */

  			pr_debug("LANE2 3.1.5, got tlvs, size %d
  ",
  				 mesg->sizeoftlvs);

  			lane2_associate_ind(dev, mesg->content.normal.mac_addr,
  					    tmp, mesg->sizeoftlvs);
  		}
  		break;
  	case l_config:
  		priv->maximum_unknown_frame_count =
  		    mesg->content.config.maximum_unknown_frame_count;
  		priv->max_unknown_frame_time =
  		    (mesg->content.config.max_unknown_frame_time * HZ);
  		priv->max_retry_count = mesg->content.config.max_retry_count;
  		priv->aging_time = (mesg->content.config.aging_time * HZ);
  		priv->forward_delay_time =
  		    (mesg->content.config.forward_delay_time * HZ);
  		priv->arp_response_time =
  		    (mesg->content.config.arp_response_time * HZ);
  		priv->flush_timeout = (mesg->content.config.flush_timeout * HZ);
  		priv->path_switching_delay =
  		    (mesg->content.config.path_switching_delay * HZ);

  		priv->lane_version = mesg->content.config.lane_version;
  					/* LANE2 */

  		priv->lane2_ops = NULL;
  		if (priv->lane_version > 1)
  			priv->lane2_ops = &lane2_ops;

  		if (dev_set_mtu(dev, mesg->content.config.mtu))

  			pr_info("%s: change_mtu to %d failed
  ",
  				dev->name, mesg->content.config.mtu);

  		priv->is_proxy = mesg->content.config.is_proxy;

  		break;
  	case l_flush_tran_id:
  		lec_set_flush_tran_id(priv, mesg->content.normal.atm_addr,
  				      mesg->content.normal.flag);
  		break;
  	case l_set_lecid:
  		priv->lecid =
  		    (unsigned short)(0xffff & mesg->content.normal.flag);
  		break;
  	case l_should_bridge:

  #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)

  	{
  		pr_debug("%s: bridge zeppelin asks about %pM
  ",
  			 dev->name, mesg->content.proxy.mac_addr);

  		if (br_fdb_test_addr_hook == NULL)
  			break;

  		if (br_fdb_test_addr_hook(dev, mesg->content.proxy.mac_addr)) {
  			/* hit from bridge table, send LE_ARP_RESPONSE */
  			struct sk_buff *skb2;
  			struct sock *sk;
  
  			pr_debug("%s: entry found, responding to zeppelin
  ",
  				 dev->name);
  			skb2 = alloc_skb(sizeof(struct atmlec_msg), GFP_ATOMIC);
  			if (skb2 == NULL)
  				break;
  			skb2->len = sizeof(struct atmlec_msg);
  			skb_copy_to_linear_data(skb2, mesg, sizeof(*mesg));
  			atm_force_charge(priv->lecd, skb2->truesize);
  			sk = sk_atm(priv->lecd);
  			skb_queue_tail(&sk->sk_receive_queue, skb2);
  			sk->sk_data_ready(sk, skb2->len);

  		}

  	}

  #endif /* defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE) */

  		break;
  	default:

  		pr_info("%s: Unknown message type %d
  ", dev->name, mesg->type);

  		dev_kfree_skb(skb);
  		return -EINVAL;
  	}
  	dev_kfree_skb(skb);
  	return 0;

  }

  static void lec_atm_close(struct atm_vcc *vcc)

  {

  	struct sk_buff *skb;
  	struct net_device *dev = (struct net_device *)vcc->proto_data;

  	struct lec_priv *priv = netdev_priv(dev);

  	priv->lecd = NULL;
  	/* Do something needful? */

  	netif_stop_queue(dev);
  	lec_arp_destroy(priv);

  	if (skb_peek(&sk_atm(vcc)->sk_receive_queue))

  		pr_info("%s closing with messages pending
  ", dev->name);

  	while ((skb = skb_dequeue(&sk_atm(vcc)->sk_receive_queue))) {

  		atm_return(vcc, skb->truesize);

  		dev_kfree_skb(skb);

  	}

  	pr_info("%s: Shut down!
  ", dev->name);

  	module_put(THIS_MODULE);

  }
  
  static struct atmdev_ops lecdev_ops = {

  	.close = lec_atm_close,
  	.send = lec_atm_send

  };
  
  static struct atm_dev lecatm_dev = {

  	.ops = &lecdev_ops,
  	.type = "lec",
  	.number = 999,		/* dummy device number */

  	.lock = __SPIN_LOCK_UNLOCKED(lecatm_dev.lock)

  };
  
  /*
   * LANE2: new argument struct sk_buff *data contains
   * the LE_ARP based TLVs introduced in the LANE2 spec
   */

  static int
  send_to_lecd(struct lec_priv *priv, atmlec_msg_type type,

  	     const unsigned char *mac_addr, const unsigned char *atm_addr,

  	     struct sk_buff *data)

  {
  	struct sock *sk;
  	struct sk_buff *skb;
  	struct atmlec_msg *mesg;

  	if (!priv || !priv->lecd)

  		return -1;

  	skb = alloc_skb(sizeof(struct atmlec_msg), GFP_ATOMIC);
  	if (!skb)
  		return -1;
  	skb->len = sizeof(struct atmlec_msg);
  	mesg = (struct atmlec_msg *)skb->data;

  	memset(mesg, 0, sizeof(struct atmlec_msg));

  	mesg->type = type;

  	if (data != NULL)
  		mesg->sizeoftlvs = data->len;

  	if (mac_addr)
  		memcpy(&mesg->content.normal.mac_addr, mac_addr, ETH_ALEN);

  	else
  		mesg->content.normal.targetless_le_arp = 1;

  	if (atm_addr)
  		memcpy(&mesg->content.normal.atm_addr, atm_addr, ATM_ESA_LEN);

  	atm_force_charge(priv->lecd, skb->truesize);

  	sk = sk_atm(priv->lecd);
  	skb_queue_tail(&sk->sk_receive_queue, skb);

  	sk->sk_data_ready(sk, skb->len);

  	if (data != NULL) {

  		pr_debug("about to send %d bytes of data
  ", data->len);

  		atm_force_charge(priv->lecd, data->truesize);
  		skb_queue_tail(&sk->sk_receive_queue, data);
  		sk->sk_data_ready(sk, skb->len);
  	}

  	return 0;

  }
  
  /* shamelessly stolen from drivers/net/net_init.c */
  static int lec_change_mtu(struct net_device *dev, int new_mtu)
  {

  	if ((new_mtu < 68) || (new_mtu > 18190))
  		return -EINVAL;
  	dev->mtu = new_mtu;
  	return 0;

  }
  
  static void lec_set_multicast_list(struct net_device *dev)
  {

  	/*
  	 * by default, all multicast frames arrive over the bus.
  	 * eventually support selective multicast service
  	 */

  }

  static const struct net_device_ops lec_netdev_ops = {
  	.ndo_open		= lec_open,
  	.ndo_stop		= lec_close,
  	.ndo_start_xmit		= lec_start_xmit,
  	.ndo_change_mtu		= lec_change_mtu,
  	.ndo_tx_timeout		= lec_tx_timeout,

  	.ndo_set_rx_mode	= lec_set_multicast_list,

  };

  static const unsigned char lec_ctrl_magic[] = {

  	0xff,
  	0x00,
  	0x01,
  	0x01
  };

  #define LEC_DATA_DIRECT_8023  2
  #define LEC_DATA_DIRECT_8025  3
  
  static int lec_is_data_direct(struct atm_vcc *vcc)

  {

  	return ((vcc->sap.blli[0].l3.tr9577.snap[4] == LEC_DATA_DIRECT_8023) ||
  		(vcc->sap.blli[0].l3.tr9577.snap[4] == LEC_DATA_DIRECT_8025));

  }

  static void lec_push(struct atm_vcc *vcc, struct sk_buff *skb)

  {

  	unsigned long flags;

  	struct net_device *dev = (struct net_device *)vcc->proto_data;

  	struct lec_priv *priv = netdev_priv(dev);

  #if DUMP_PACKETS > 0

  	printk(KERN_DEBUG "%s: vcc vpi:%d vci:%d
  ",
  	       dev->name, vcc->vpi, vcc->vci);

  #endif

  	if (!skb) {

  		pr_debug("%s: null skb
  ", dev->name);

  		lec_vcc_close(priv, vcc);
  		return;
  	}

  #if DUMP_PACKETS >= 2

  #define MAX_SKB_DUMP 99

  #elif DUMP_PACKETS >= 1

  #define MAX_SKB_DUMP 30
  #endif
  #if DUMP_PACKETS > 0
  	printk(KERN_DEBUG "%s: rcv datalen:%ld lecid:%4.4x
  ",
  	       dev->name, skb->len, priv->lecid);
  	print_hex_dump(KERN_DEBUG, "", DUMP_OFFSET, 16, 1,
  		       skb->data, min(MAX_SKB_DUMP, skb->len), true);

  #endif /* DUMP_PACKETS > 0 */

  	if (memcmp(skb->data, lec_ctrl_magic, 4) == 0) {
  				/* Control frame, to daemon */

  		struct sock *sk = sk_atm(vcc);

  		pr_debug("%s: To daemon
  ", dev->name);

  		skb_queue_tail(&sk->sk_receive_queue, skb);
  		sk->sk_data_ready(sk, skb->len);
  	} else {		/* Data frame, queue to protocol handlers */

  		struct lec_arp_table *entry;

  		unsigned char *src, *dst;
  
  		atm_return(vcc, skb->truesize);

  		if (*(__be16 *) skb->data == htons(priv->lecid) ||

  		    !priv->lecd || !(dev->flags & IFF_UP)) {
  			/*
  			 * Probably looping back, or if lecd is missing,
  			 * lecd has gone down
  			 */

  			pr_debug("Ignoring frame...
  ");

  			dev_kfree_skb(skb);
  			return;
  		}

  #ifdef CONFIG_TR

  		if (priv->is_trdev)
  			dst = ((struct lecdatahdr_8025 *)skb->data)->h_dest;
  		else

  #endif

  			dst = ((struct lecdatahdr_8023 *)skb->data)->h_dest;

  		/*
  		 * If this is a Data Direct VCC, and the VCC does not match

  		 * the LE_ARP cache entry, delete the LE_ARP cache entry.
  		 */
  		spin_lock_irqsave(&priv->lec_arp_lock, flags);
  		if (lec_is_data_direct(vcc)) {
  #ifdef CONFIG_TR
  			if (priv->is_trdev)

  				src =
  				    ((struct lecdatahdr_8025 *)skb->data)->
  				    h_source;

  			else
  #endif

  				src =
  				    ((struct lecdatahdr_8023 *)skb->data)->
  				    h_source;

  			entry = lec_arp_find(priv, src);
  			if (entry && entry->vcc != vcc) {
  				lec_arp_remove(priv, entry);

  				lec_arp_put(entry);

  			}
  		}
  		spin_unlock_irqrestore(&priv->lec_arp_lock, flags);

  		if (!(dst[0] & 0x01) &&	/* Never filter Multi/Broadcast */
  		    !priv->is_proxy &&	/* Proxy wants all the packets */

  		    memcmp(dst, dev->dev_addr, dev->addr_len)) {

  			dev_kfree_skb(skb);
  			return;
  		}

  		if (!hlist_empty(&priv->lec_arp_empty_ones))

  			lec_arp_check_empties(priv, vcc, skb);

  		skb_pull(skb, 2);	/* skip lec_id */

  #ifdef CONFIG_TR

  		if (priv->is_trdev)
  			skb->protocol = tr_type_trans(skb, dev);
  		else

  #endif

  			skb->protocol = eth_type_trans(skb, dev);

  		dev->stats.rx_packets++;
  		dev->stats.rx_bytes += skb->len;

  		memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
  		netif_rx(skb);
  	}

  }

  static void lec_pop(struct atm_vcc *vcc, struct sk_buff *skb)

  {
  	struct lec_vcc_priv *vpriv = LEC_VCC_PRIV(vcc);
  	struct net_device *dev = skb->dev;
  
  	if (vpriv == NULL) {

  		pr_info("vpriv = NULL!?!?!?
  ");

  		return;
  	}
  
  	vpriv->old_pop(vcc, skb);
  
  	if (vpriv->xoff && atm_may_send(vcc, 0)) {
  		vpriv->xoff = 0;
  		if (netif_running(dev) && netif_queue_stopped(dev))
  			netif_wake_queue(dev);
  	}
  }

  static int lec_vcc_attach(struct atm_vcc *vcc, void __user *arg)

  {
  	struct lec_vcc_priv *vpriv;

  	int bytes_left;
  	struct atmlec_ioc ioc_data;
  
  	/* Lecd must be up in this case */
  	bytes_left = copy_from_user(&ioc_data, arg, sizeof(struct atmlec_ioc));

  	if (bytes_left != 0)
  		pr_info("copy from user failed for %d bytes
  ", bytes_left);

  	if (ioc_data.dev_num < 0 || ioc_data.dev_num >= MAX_LEC_ITF ||
  	    !dev_lec[ioc_data.dev_num])
  		return -EINVAL;

  	vpriv = kmalloc(sizeof(struct lec_vcc_priv), GFP_KERNEL);
  	if (!vpriv)

  		return -ENOMEM;
  	vpriv->xoff = 0;
  	vpriv->old_pop = vcc->pop;
  	vcc->user_back = vpriv;
  	vcc->pop = lec_pop;

  	lec_vcc_added(netdev_priv(dev_lec[ioc_data.dev_num]),

  		      &ioc_data, vcc, vcc->push);
  	vcc->proto_data = dev_lec[ioc_data.dev_num];
  	vcc->push = lec_push;
  	return 0;

  }

  static int lec_mcast_attach(struct atm_vcc *vcc, int arg)

  {

  	if (arg < 0 || arg >= MAX_LEC_ITF || !dev_lec[arg])
  		return -EINVAL;
  	vcc->proto_data = dev_lec[arg];

  	return lec_mcast_make(netdev_priv(dev_lec[arg]), vcc);

  }
  
  /* Initialize device. */

  static int lecd_attach(struct atm_vcc *vcc, int arg)
  {
  	int i;
  	struct lec_priv *priv;
  
  	if (arg < 0)
  		i = 0;
  	else
  		i = arg;

  #ifdef CONFIG_TR

  	if (arg >= MAX_LEC_ITF)
  		return -EINVAL;
  #else				/* Reserve the top NUM_TR_DEVS for TR */
  	if (arg >= (MAX_LEC_ITF - NUM_TR_DEVS))
  		return -EINVAL;

  #endif

  	if (!dev_lec[i]) {
  		int is_trdev, size;

  		is_trdev = 0;
  		if (i >= (MAX_LEC_ITF - NUM_TR_DEVS))
  			is_trdev = 1;

  		size = sizeof(struct lec_priv);

  #ifdef CONFIG_TR

  		if (is_trdev)
  			dev_lec[i] = alloc_trdev(size);
  		else

  #endif

  			dev_lec[i] = alloc_etherdev(size);
  		if (!dev_lec[i])
  			return -ENOMEM;

  		dev_lec[i]->netdev_ops = &lec_netdev_ops;

  		snprintf(dev_lec[i]->name, IFNAMSIZ, "lec%d", i);
  		if (register_netdev(dev_lec[i])) {
  			free_netdev(dev_lec[i]);
  			return -EINVAL;
  		}

  		priv = netdev_priv(dev_lec[i]);

  		priv->is_trdev = is_trdev;

  	} else {

  		priv = netdev_priv(dev_lec[i]);

  		if (priv->lecd)
  			return -EADDRINUSE;
  	}
  	lec_arp_init(priv);
  	priv->itfnum = i;	/* LANE2 addition */
  	priv->lecd = vcc;
  	vcc->dev = &lecatm_dev;
  	vcc_insert_socket(sk_atm(vcc));
  
  	vcc->proto_data = dev_lec[i];
  	set_bit(ATM_VF_META, &vcc->flags);
  	set_bit(ATM_VF_READY, &vcc->flags);
  
  	/* Set default values to these variables */
  	priv->maximum_unknown_frame_count = 1;
  	priv->max_unknown_frame_time = (1 * HZ);
  	priv->vcc_timeout_period = (1200 * HZ);
  	priv->max_retry_count = 1;
  	priv->aging_time = (300 * HZ);
  	priv->forward_delay_time = (15 * HZ);
  	priv->topology_change = 0;
  	priv->arp_response_time = (1 * HZ);
  	priv->flush_timeout = (4 * HZ);
  	priv->path_switching_delay = (6 * HZ);

  	if (dev_lec[i]->flags & IFF_UP)

  		netif_start_queue(dev_lec[i]);

  	__module_get(THIS_MODULE);
  	return i;

  }
  
  #ifdef CONFIG_PROC_FS

  static const char *lec_arp_get_status_string(unsigned char status)

  {

  	static const char *const lec_arp_status_string[] = {

  		"ESI_UNKNOWN       ",
  		"ESI_ARP_PENDING   ",
  		"ESI_VC_PENDING    ",
  		"<Undefined>       ",
  		"ESI_FLUSH_PENDING ",
  		"ESI_FORWARD_DIRECT"
  	};
  
  	if (status > ESI_FORWARD_DIRECT)
  		status = 3;	/* ESI_UNDEFINED */
  	return lec_arp_status_string[status];
  }
  
  static void lec_info(struct seq_file *seq, struct lec_arp_table *entry)
  {
  	int i;
  
  	for (i = 0; i < ETH_ALEN; i++)
  		seq_printf(seq, "%2.2x", entry->mac_addr[i] & 0xff);
  	seq_printf(seq, " ");
  	for (i = 0; i < ATM_ESA_LEN; i++)
  		seq_printf(seq, "%2.2x", entry->atm_addr[i] & 0xff);
  	seq_printf(seq, " %s %4.4x", lec_arp_get_status_string(entry->status),
  		   entry->flags & 0xffff);
  	if (entry->vcc)
  		seq_printf(seq, "%3d %3d ", entry->vcc->vpi, entry->vcc->vci);
  	else

  		seq_printf(seq, "        ");

  	if (entry->recv_vcc) {
  		seq_printf(seq, "     %3d %3d", entry->recv_vcc->vpi,
  			   entry->recv_vcc->vci);

  	}
  	seq_putc(seq, '
  ');

  }

  struct lec_state {
  	unsigned long flags;
  	struct lec_priv *locked;

  	struct hlist_node *node;

  	struct net_device *dev;
  	int itf;
  	int arp_table;
  	int misc_table;
  };

  static void *lec_tbl_walk(struct lec_state *state, struct hlist_head *tbl,

  			  loff_t *l)
  {

  	struct hlist_node *e = state->node;
  	struct lec_arp_table *tmp;

  
  	if (!e)

  		e = tbl->first;

  	if (e == SEQ_START_TOKEN) {

  		e = tbl->first;

  		--*l;
  	}

  
  	hlist_for_each_entry_from(tmp, e, next) {

  		if (--*l < 0)
  			break;
  	}

  	state->node = e;

  	return (*l < 0) ? state : NULL;
  }
  
  static void *lec_arp_walk(struct lec_state *state, loff_t *l,

  			  struct lec_priv *priv)

  {
  	void *v = NULL;
  	int p;
  
  	for (p = state->arp_table; p < LEC_ARP_TABLE_SIZE; p++) {

  		v = lec_tbl_walk(state, &priv->lec_arp_tables[p], l);

  		if (v)
  			break;
  	}
  	state->arp_table = p;
  	return v;
  }
  
  static void *lec_misc_walk(struct lec_state *state, loff_t *l,
  			   struct lec_priv *priv)
  {

  	struct hlist_head *lec_misc_tables[] = {
  		&priv->lec_arp_empty_ones,
  		&priv->lec_no_forward,
  		&priv->mcast_fwds

  	};
  	void *v = NULL;
  	int q;
  
  	for (q = state->misc_table; q < ARRAY_SIZE(lec_misc_tables); q++) {
  		v = lec_tbl_walk(state, lec_misc_tables[q], l);
  		if (v)
  			break;
  	}
  	state->misc_table = q;
  	return v;
  }
  
  static void *lec_priv_walk(struct lec_state *state, loff_t *l,
  			   struct lec_priv *priv)
  {
  	if (!state->locked) {
  		state->locked = priv;
  		spin_lock_irqsave(&priv->lec_arp_lock, state->flags);
  	}

  	if (!lec_arp_walk(state, l, priv) && !lec_misc_walk(state, l, priv)) {

  		spin_unlock_irqrestore(&priv->lec_arp_lock, state->flags);
  		state->locked = NULL;
  		/* Partial state reset for the next time we get called */
  		state->arp_table = state->misc_table = 0;
  	}
  	return state->locked;
  }
  
  static void *lec_itf_walk(struct lec_state *state, loff_t *l)
  {
  	struct net_device *dev;
  	void *v;
  
  	dev = state->dev ? state->dev : dev_lec[state->itf];

  	v = (dev && netdev_priv(dev)) ?
  		lec_priv_walk(state, l, netdev_priv(dev)) : NULL;

  	if (!v && dev) {
  		dev_put(dev);
  		/* Partial state reset for the next time we get called */
  		dev = NULL;
  	}
  	state->dev = dev;
  	return v;
  }
  
  static void *lec_get_idx(struct lec_state *state, loff_t l)
  {
  	void *v = NULL;
  
  	for (; state->itf < MAX_LEC_ITF; state->itf++) {
  		v = lec_itf_walk(state, &l);
  		if (v)
  			break;
  	}

  	return v;

  }
  
  static void *lec_seq_start(struct seq_file *seq, loff_t *pos)
  {
  	struct lec_state *state = seq->private;
  
  	state->itf = 0;
  	state->dev = NULL;
  	state->locked = NULL;
  	state->arp_table = 0;
  	state->misc_table = 0;

  	state->node = SEQ_START_TOKEN;

  	return *pos ? lec_get_idx(state, *pos) : SEQ_START_TOKEN;

  }
  
  static void lec_seq_stop(struct seq_file *seq, void *v)
  {
  	struct lec_state *state = seq->private;
  
  	if (state->dev) {
  		spin_unlock_irqrestore(&state->locked->lec_arp_lock,
  				       state->flags);
  		dev_put(state->dev);
  	}
  }
  
  static void *lec_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {
  	struct lec_state *state = seq->private;
  
  	v = lec_get_idx(state, 1);
  	*pos += !!PTR_ERR(v);
  	return v;
  }
  
  static int lec_seq_show(struct seq_file *seq, void *v)
  {

  	static const char lec_banner[] =
  	    "Itf  MAC          ATM destination"

  	    "                          Status            Flags "
  	    "VPI/VCI Recv VPI/VCI
  ";

  	if (v == SEQ_START_TOKEN)

  		seq_puts(seq, lec_banner);
  	else {
  		struct lec_state *state = seq->private;

  		struct net_device *dev = state->dev;

  		struct lec_arp_table *entry = hlist_entry(state->node,
  							  struct lec_arp_table,
  							  next);

  
  		seq_printf(seq, "%s ", dev->name);

  		lec_info(seq, entry);

  	}
  	return 0;
  }

  static const struct seq_operations lec_seq_ops = {

  	.start = lec_seq_start,
  	.next = lec_seq_next,
  	.stop = lec_seq_stop,
  	.show = lec_seq_show,

  };
  
  static int lec_seq_open(struct inode *inode, struct file *file)
  {

  	return seq_open_private(file, &lec_seq_ops, sizeof(struct lec_state));

  }

  static const struct file_operations lec_seq_fops = {

  	.owner = THIS_MODULE,
  	.open = lec_seq_open,
  	.read = seq_read,
  	.llseek = seq_lseek,

  	.release = seq_release_private,

  };
  #endif
  
  static int lane_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
  {
  	struct atm_vcc *vcc = ATM_SD(sock);
  	int err = 0;

  	switch (cmd) {

  	case ATMLEC_CTRL:
  	case ATMLEC_MCAST:
  	case ATMLEC_DATA:
  		if (!capable(CAP_NET_ADMIN))
  			return -EPERM;
  		break;
  	default:
  		return -ENOIOCTLCMD;

  	}
  
  	switch (cmd) {

  	case ATMLEC_CTRL:
  		err = lecd_attach(vcc, (int)arg);
  		if (err >= 0)
  			sock->state = SS_CONNECTED;
  		break;
  	case ATMLEC_MCAST:
  		err = lec_mcast_attach(vcc, (int)arg);
  		break;
  	case ATMLEC_DATA:
  		err = lec_vcc_attach(vcc, (void __user *)arg);
  		break;

  	}
  
  	return err;
  }
  
  static struct atm_ioctl lane_ioctl_ops = {

  	.owner = THIS_MODULE,
  	.ioctl = lane_ioctl,

  };
  
  static int __init lane_module_init(void)
  {
  #ifdef CONFIG_PROC_FS
  	struct proc_dir_entry *p;

  	p = proc_create("lec", S_IRUGO, atm_proc_root, &lec_seq_fops);

  	if (!p) {

  		pr_err("Unable to initialize /proc/net/atm/lec
  ");

  		return -ENOMEM;
  	}

  #endif
  
  	register_atm_ioctl(&lane_ioctl_ops);

  	pr_info("lec.c: initialized
  ");

  	return 0;

  }
  
  static void __exit lane_module_cleanup(void)
  {

  	int i;

  
  	remove_proc_entry("lec", atm_proc_root);
  
  	deregister_atm_ioctl(&lane_ioctl_ops);

  	for (i = 0; i < MAX_LEC_ITF; i++) {
  		if (dev_lec[i] != NULL) {

  			unregister_netdev(dev_lec[i]);

  			free_netdev(dev_lec[i]);
  			dev_lec[i] = NULL;
  		}
  	}

  }
  
  module_init(lane_module_init);
  module_exit(lane_module_cleanup);
  
  /*
   * LANE2: 3.1.3, LE_RESOLVE.request
   * Non force allocates memory and fills in *tlvs, fills in *sizeoftlvs.
   * If sizeoftlvs == NULL the default TLVs associated with with this
   * lec will be used.
   * If dst_mac == NULL, targetless LE_ARP will be sent
   */

  static int lane2_resolve(struct net_device *dev, const u8 *dst_mac, int force,

  			 u8 **tlvs, u32 *sizeoftlvs)

  {
  	unsigned long flags;

  	struct lec_priv *priv = netdev_priv(dev);

  	struct lec_arp_table *table;
  	struct sk_buff *skb;
  	int retval;

  	if (force == 0) {

  		spin_lock_irqsave(&priv->lec_arp_lock, flags);

  		table = lec_arp_find(priv, dst_mac);

  		spin_unlock_irqrestore(&priv->lec_arp_lock, flags);

  		if (table == NULL)
  			return -1;

  		*tlvs = kmemdup(table->tlvs, table->sizeoftlvs, GFP_ATOMIC);

  		if (*tlvs == NULL)
  			return -1;

  		*sizeoftlvs = table->sizeoftlvs;
  
  		return 0;
  	}

  
  	if (sizeoftlvs == NULL)
  		retval = send_to_lecd(priv, l_arp_xmt, dst_mac, NULL, NULL);

  	else {
  		skb = alloc_skb(*sizeoftlvs, GFP_ATOMIC);
  		if (skb == NULL)
  			return -1;
  		skb->len = *sizeoftlvs;

  		skb_copy_to_linear_data(skb, *tlvs, *sizeoftlvs);

  		retval = send_to_lecd(priv, l_arp_xmt, dst_mac, NULL, skb);
  	}

  	return retval;
  }

  
  /*
   * LANE2: 3.1.4, LE_ASSOCIATE.request
   * Associate the *tlvs with the *lan_dst address.
   * Will overwrite any previous association
   * Returns 1 for success, 0 for failure (out of memory)
   *
   */

  static int lane2_associate_req(struct net_device *dev, const u8 *lan_dst,
  			       const u8 *tlvs, u32 sizeoftlvs)

  {

  	int retval;
  	struct sk_buff *skb;

  	struct lec_priv *priv = netdev_priv(dev);

  
  	if (compare_ether_addr(lan_dst, dev->dev_addr))

  		return 0;	/* not our mac address */

  
  	kfree(priv->tlvs);	/* NULL if there was no previous association */

  	priv->tlvs = kmemdup(tlvs, sizeoftlvs, GFP_KERNEL);

  	if (priv->tlvs == NULL)

  		return 0;

  	priv->sizeoftlvs = sizeoftlvs;

  
  	skb = alloc_skb(sizeoftlvs, GFP_ATOMIC);
  	if (skb == NULL)
  		return 0;
  	skb->len = sizeoftlvs;

  	skb_copy_to_linear_data(skb, tlvs, sizeoftlvs);

  	retval = send_to_lecd(priv, l_associate_req, NULL, NULL, skb);
  	if (retval != 0)

  		pr_info("lec.c: lane2_associate_req() failed
  ");

  	/*
  	 * If the previous association has changed we must
  	 * somehow notify other LANE entities about the change
  	 */

  	return 1;

  }
  
  /*
   * LANE2: 3.1.5, LE_ASSOCIATE.indication
   *
   */

  static void lane2_associate_ind(struct net_device *dev, const u8 *mac_addr,
  				const u8 *tlvs, u32 sizeoftlvs)

  {
  #if 0

  	int i = 0;

  #endif

  	struct lec_priv *priv = netdev_priv(dev);

  #if 0				/*
  				 * Why have the TLVs in LE_ARP entries
  				 * since we do not use them? When you
  				 * uncomment this code, make sure the
  				 * TLVs get freed when entry is killed
  				 */
  	struct lec_arp_table *entry = lec_arp_find(priv, mac_addr);

  	if (entry == NULL)
  		return;		/* should not happen */

  	kfree(entry->tlvs);

  	entry->tlvs = kmemdup(tlvs, sizeoftlvs, GFP_KERNEL);

  	if (entry->tlvs == NULL)
  		return;

  	entry->sizeoftlvs = sizeoftlvs;

  #endif
  #if 0

  	pr_info("
  ");
  	pr_info("dump of tlvs, sizeoftlvs=%d
  ", sizeoftlvs);

  	while (i < sizeoftlvs)

  		pr_cont("%02x ", tlvs[i++]);

  	pr_cont("
  ");

  #endif

  	/* tell MPOA about the TLVs we saw */
  	if (priv->lane2_ops && priv->lane2_ops->associate_indicator) {
  		priv->lane2_ops->associate_indicator(dev, mac_addr,
  						     tlvs, sizeoftlvs);
  	}

  }
  
  /*
   * Here starts what used to lec_arpc.c
   *
   * lec_arpc.c was added here when making
   * lane client modular. October 1997

   */
  
  #include <linux/types.h>

  #include <linux/timer.h>

  #include <linux/param.h>

  #include <linux/atomic.h>

  #include <linux/inetdevice.h>
  #include <net/route.h>

  #if 0

  #define pr_debug(format, args...)

  /*

    #define pr_debug printk

  */
  #endif
  #define DEBUG_ARP_TABLE 0
  
  #define LEC_ARP_REFRESH_INTERVAL (3*HZ)

  static void lec_arp_check_expire(struct work_struct *work);

  static void lec_arp_expire_arp(unsigned long data);

  /*

   * Arp table funcs
   */

  #define HASH(ch) (ch & (LEC_ARP_TABLE_SIZE - 1))

  
  /*
   * Initialization of arp-cache
   */

  static void lec_arp_init(struct lec_priv *priv)

  {

  	unsigned short i;

  	for (i = 0; i < LEC_ARP_TABLE_SIZE; i++)

  		INIT_HLIST_HEAD(&priv->lec_arp_tables[i]);

  	INIT_HLIST_HEAD(&priv->lec_arp_empty_ones);
  	INIT_HLIST_HEAD(&priv->lec_no_forward);
  	INIT_HLIST_HEAD(&priv->mcast_fwds);

  	spin_lock_init(&priv->lec_arp_lock);

  	INIT_DELAYED_WORK(&priv->lec_arp_work, lec_arp_check_expire);

  	schedule_delayed_work(&priv->lec_arp_work, LEC_ARP_REFRESH_INTERVAL);

  }

  static void lec_arp_clear_vccs(struct lec_arp_table *entry)

  {

  	if (entry->vcc) {

  		struct atm_vcc *vcc = entry->vcc;
  		struct lec_vcc_priv *vpriv = LEC_VCC_PRIV(vcc);

  		struct net_device *dev = (struct net_device *)vcc->proto_data;

  		vcc->pop = vpriv->old_pop;

  		if (vpriv->xoff)
  			netif_wake_queue(dev);
  		kfree(vpriv);
  		vcc->user_back = NULL;

  		vcc->push = entry->old_push;

  		vcc_release_async(vcc, -EPIPE);

  		entry->vcc = NULL;

  	}
  	if (entry->recv_vcc) {
  		entry->recv_vcc->push = entry->old_recv_push;

  		vcc_release_async(entry->recv_vcc, -EPIPE);

  		entry->recv_vcc = NULL;
  	}

  }
  
  /*
   * Insert entry to lec_arp_table
   * LANE2: Add to the end of the list to satisfy 8.1.13
   */

  static inline void

  lec_arp_add(struct lec_priv *priv, struct lec_arp_table *entry)

  {

  	struct hlist_head *tmp;

  	tmp = &priv->lec_arp_tables[HASH(entry->mac_addr[ETH_ALEN - 1])];
  	hlist_add_head(&entry->next, tmp);

  	pr_debug("Added entry:%pM
  ", entry->mac_addr);

  }
  
  /*
   * Remove entry from lec_arp_table
   */

  static int
  lec_arp_remove(struct lec_priv *priv, struct lec_arp_table *to_remove)

  {

  	struct hlist_node *node;
  	struct lec_arp_table *entry;
  	int i, remove_vcc = 1;

  	if (!to_remove)

  		return -1;

  
  	hlist_del(&to_remove->next);

  	del_timer(&to_remove->timer);

  	/*
  	 * If this is the only MAC connected to this VCC,
  	 * also tear down the VCC
  	 */

  	if (to_remove->status >= ESI_FLUSH_PENDING) {
  		/*
  		 * ESI_FLUSH_PENDING, ESI_FORWARD_DIRECT
  		 */

  		for (i = 0; i < LEC_ARP_TABLE_SIZE; i++) {

  			hlist_for_each_entry(entry, node,
  					     &priv->lec_arp_tables[i], next) {

  				if (memcmp(to_remove->atm_addr,
  					   entry->atm_addr, ATM_ESA_LEN) == 0) {

  					remove_vcc = 0;
  					break;
  				}
  			}
  		}
  		if (remove_vcc)
  			lec_arp_clear_vccs(to_remove);
  	}
  	skb_queue_purge(&to_remove->tx_wait);	/* FIXME: good place for this? */

  	pr_debug("Removed entry:%pM
  ", to_remove->mac_addr);

  	return 0;

  }
  
  #if DEBUG_ARP_TABLE

  static const char *get_status_string(unsigned char st)

  {

  	switch (st) {
  	case ESI_UNKNOWN:
  		return "ESI_UNKNOWN";
  	case ESI_ARP_PENDING:
  		return "ESI_ARP_PENDING";
  	case ESI_VC_PENDING:
  		return "ESI_VC_PENDING";
  	case ESI_FLUSH_PENDING:
  		return "ESI_FLUSH_PENDING";
  	case ESI_FORWARD_DIRECT:
  		return "ESI_FORWARD_DIRECT";

  	}

  	return "<UNKNOWN>";

  }

  static void dump_arp_table(struct lec_priv *priv)

  {

  	struct hlist_node *node;

  	struct lec_arp_table *rulla;

  	char buf[256];
  	int i, j, offset;

  	pr_info("Dump %p:
  ", priv);

  	for (i = 0; i < LEC_ARP_TABLE_SIZE; i++) {

  		hlist_for_each_entry(rulla, node,
  				     &priv->lec_arp_tables[i], next) {

  			offset = 0;
  			offset += sprintf(buf, "%d: %p
  ", i, rulla);

  			offset += sprintf(buf + offset, "Mac: %pM",
  					  rulla->mac_addr);
  			offset += sprintf(buf + offset, " Atm:");

  			for (j = 0; j < ATM_ESA_LEN; j++) {
  				offset += sprintf(buf + offset,
  						  "%2.2x ",
  						  rulla->atm_addr[j] & 0xff);
  			}
  			offset += sprintf(buf + offset,
  					  "Vcc vpi:%d vci:%d, Recv_vcc vpi:%d vci:%d Last_used:%lx, Timestamp:%lx, No_tries:%d ",
  					  rulla->vcc ? rulla->vcc->vpi : 0,
  					  rulla->vcc ? rulla->vcc->vci : 0,
  					  rulla->recv_vcc ? rulla->recv_vcc->
  					  vpi : 0,
  					  rulla->recv_vcc ? rulla->recv_vcc->
  					  vci : 0, rulla->last_used,
  					  rulla->timestamp, rulla->no_tries);
  			offset +=
  			    sprintf(buf + offset,
  				    "Flags:%x, Packets_flooded:%x, Status: %s ",
  				    rulla->flags, rulla->packets_flooded,
  				    get_status_string(rulla->status));

  			pr_info("%s
  ", buf);

  		}

  	}

  
  	if (!hlist_empty(&priv->lec_no_forward))

  		pr_info("No forward
  ");

  	hlist_for_each_entry(rulla, node, &priv->lec_no_forward, next) {

  		offset = 0;

  		offset += sprintf(buf + offset, "Mac: %pM", rulla->mac_addr);
  		offset += sprintf(buf + offset, " Atm:");

  		for (j = 0; j < ATM_ESA_LEN; j++) {
  			offset += sprintf(buf + offset, "%2.2x ",
  					  rulla->atm_addr[j] & 0xff);
  		}
  		offset += sprintf(buf + offset,
  				  "Vcc vpi:%d vci:%d, Recv_vcc vpi:%d vci:%d Last_used:%lx, Timestamp:%lx, No_tries:%d ",
  				  rulla->vcc ? rulla->vcc->vpi : 0,
  				  rulla->vcc ? rulla->vcc->vci : 0,
  				  rulla->recv_vcc ? rulla->recv_vcc->vpi : 0,
  				  rulla->recv_vcc ? rulla->recv_vcc->vci : 0,
  				  rulla->last_used,
  				  rulla->timestamp, rulla->no_tries);
  		offset += sprintf(buf + offset,
  				  "Flags:%x, Packets_flooded:%x, Status: %s ",
  				  rulla->flags, rulla->packets_flooded,
  				  get_status_string(rulla->status));

  		pr_info("%s
  ", buf);

  	}

  
  	if (!hlist_empty(&priv->lec_arp_empty_ones))

  		pr_info("Empty ones
  ");

  	hlist_for_each_entry(rulla, node, &priv->lec_arp_empty_ones, next) {

  		offset = 0;

  		offset += sprintf(buf + offset, "Mac: %pM", rulla->mac_addr);
  		offset += sprintf(buf + offset, " Atm:");

  		for (j = 0; j < ATM_ESA_LEN; j++) {
  			offset += sprintf(buf + offset, "%2.2x ",
  					  rulla->atm_addr[j] & 0xff);
  		}
  		offset += sprintf(buf + offset,
  				  "Vcc vpi:%d vci:%d, Recv_vcc vpi:%d vci:%d Last_used:%lx, Timestamp:%lx, No_tries:%d ",
  				  rulla->vcc ? rulla->vcc->vpi : 0,
  				  rulla->vcc ? rulla->vcc->vci : 0,
  				  rulla->recv_vcc ? rulla->recv_vcc->vpi : 0,
  				  rulla->recv_vcc ? rulla->recv_vcc->vci : 0,
  				  rulla->last_used,
  				  rulla->timestamp, rulla->no_tries);
  		offset += sprintf(buf + offset,
  				  "Flags:%x, Packets_flooded:%x, Status: %s ",
  				  rulla->flags, rulla->packets_flooded,
  				  get_status_string(rulla->status));

  		pr_info("%s", buf);

  	}

  	if (!hlist_empty(&priv->mcast_fwds))

  		pr_info("Multicast Forward VCCs
  ");

  	hlist_for_each_entry(rulla, node, &priv->mcast_fwds, next) {

  		offset = 0;

  		offset += sprintf(buf + offset, "Mac: %pM", rulla->mac_addr);
  		offset += sprintf(buf + offset, " Atm:");

  		for (j = 0; j < ATM_ESA_LEN; j++) {
  			offset += sprintf(buf + offset, "%2.2x ",
  					  rulla->atm_addr[j] & 0xff);
  		}
  		offset += sprintf(buf + offset,
  				  "Vcc vpi:%d vci:%d, Recv_vcc vpi:%d vci:%d Last_used:%lx, Timestamp:%lx, No_tries:%d ",
  				  rulla->vcc ? rulla->vcc->vpi : 0,
  				  rulla->vcc ? rulla->vcc->vci : 0,
  				  rulla->recv_vcc ? rulla->recv_vcc->vpi : 0,
  				  rulla->recv_vcc ? rulla->recv_vcc->vci : 0,
  				  rulla->last_used,
  				  rulla->timestamp, rulla->no_tries);
  		offset += sprintf(buf + offset,
  				  "Flags:%x, Packets_flooded:%x, Status: %s ",
  				  rulla->flags, rulla->packets_flooded,
  				  get_status_string(rulla->status));

  		pr_info("%s
  ", buf);

  	}

  }

  #else
  #define dump_arp_table(priv) do { } while (0)
  #endif

  
  /*
   * Destruction of arp-cache
   */

  static void lec_arp_destroy(struct lec_priv *priv)

  {
  	unsigned long flags;

  	struct hlist_node *node, *next;
  	struct lec_arp_table *entry;

  	int i;

  	cancel_delayed_work_sync(&priv->lec_arp_work);

  	/*
  	 * Remove all entries
  	 */

  
  	spin_lock_irqsave(&priv->lec_arp_lock, flags);

  	for (i = 0; i < LEC_ARP_TABLE_SIZE; i++) {

  		hlist_for_each_entry_safe(entry, node, next,
  					  &priv->lec_arp_tables[i], next) {

  			lec_arp_remove(priv, entry);

  			lec_arp_put(entry);

  		}

  		INIT_HLIST_HEAD(&priv->lec_arp_tables[i]);

  	}

  	hlist_for_each_entry_safe(entry, node, next,
  				  &priv->lec_arp_empty_ones, next) {

  		del_timer_sync(&entry->timer);
  		lec_arp_clear_vccs(entry);

  		hlist_del(&entry->next);

  		lec_arp_put(entry);

  	}

  	INIT_HLIST_HEAD(&priv->lec_arp_empty_ones);

  	hlist_for_each_entry_safe(entry, node, next,
  				  &priv->lec_no_forward, next) {

  		del_timer_sync(&entry->timer);
  		lec_arp_clear_vccs(entry);

  		hlist_del(&entry->next);

  		lec_arp_put(entry);

  	}

  	INIT_HLIST_HEAD(&priv->lec_no_forward);
  
  	hlist_for_each_entry_safe(entry, node, next, &priv->mcast_fwds, next) {

  		/* No timer, LANEv2 7.1.20 and 2.3.5.3 */
  		lec_arp_clear_vccs(entry);

  		hlist_del(&entry->next);

  		lec_arp_put(entry);

  	}

  	INIT_HLIST_HEAD(&priv->mcast_fwds);

  	priv->mcast_vcc = NULL;