lec.c

/*
 * lec.c: Lan Emulation driver 
 * Marko Kiiskila mkiiskila@yahoo.com
 *
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/bitops.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 <asm/uaccess.h>
#include <net/arp.h>
#include <net/dst.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/proc_fs.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 <linux/if_bridge.h>
#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"

#if 0
#define DPRINTK printk
#else
#define DPRINTK(format,args...)
#endif

#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 int lec_start_xmit(struct sk_buff *skb, struct net_device *dev);
static int lec_close(struct net_device *dev);
static struct net_device_stats *lec_get_stats(struct net_device *dev);
static void lec_init(struct net_device *dev);
static struct lec_arp_table* lec_arp_find(struct lec_priv *priv,
                                                     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, u8 *mac_address,
                          u8 *tlvs, u32 sizeoftlvs);
static int lane2_resolve(struct net_device *dev, u8 *dst_mac, int force,
                  u8 **tlvs, u32 *sizeoftlvs);
static int lane2_associate_req (struct net_device *dev, u8 *lan_dst,
                         u8 *tlvs, u32 sizeoftlvs);

static int lec_addr_delete(struct lec_priv *priv, 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,
				       unsigned char *mac_to_find,
				       int is_rdesc,
				       struct lec_arp_table **ret_entry);
static void lec_arp_update(struct lec_priv *priv, unsigned char *mac_addr,
			   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,
				  unsigned char *atm_addr,
				  unsigned long tran_id);
static void lec_vcc_added(struct lec_priv *priv, 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);

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)
{
        struct ethhdr *eth;
        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 */
        eth = (struct ethhdr *)skb->data;
        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 = (struct lec_priv *)dev->priv;
                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);
        }

        return;
}
#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;
        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(uint16_t));
        else {
                memcpy(&rdesc[4], &trh->rseg[1], sizeof(uint16_t));
                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)
{
        struct lec_priv *priv = (struct lec_priv *)dev->priv;
        
	netif_start_queue(dev);
        memset(&priv->stats,0,sizeof(struct net_device_stats));
        
        return 0;
}

static __inline__ void
lec_send(struct atm_vcc *vcc, struct sk_buff *skb, struct lec_priv *priv)
{
	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) {
		priv->stats.tx_dropped++;
		return;
	}

	priv->stats.tx_packets++;
	priv->stats.tx_bytes += skb->len;
}

static void
lec_tx_timeout(struct net_device *dev)
{
	printk(KERN_INFO "%s: tx timeout\n", dev->name);
	dev->trans_start = jiffies;
	netif_wake_queue(dev);
}

static int 
lec_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct sk_buff *skb2;
        struct lec_priv *priv = (struct lec_priv *)dev->priv;
        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;
#if DUMP_PACKETS > 0
        char buf[300];
        int i=0;
#endif /* DUMP_PACKETS >0 */
        
        DPRINTK("lec_start_xmit called\n");  
        if (!priv->lecd) {
                printk("%s:No lecd attached\n",dev->name);
                priv->stats.tx_errors++;
                netif_stop_queue(dev);
                return -EUNATCH;
        } 

        DPRINTK("skbuff head:%lx data:%lx tail:%lx end:%lx\n",
                (long)skb->head, (long)skb->data, (long)skb->tail,
                (long)skb->end);
#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) {

                DPRINTK("lec_start_xmit: reallocating skb\n");
                skb2 = skb_realloc_headroom(skb, LEC_HEADER_LEN);
                kfree_skb(skb);
                if (skb2 == NULL) return 0;
                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 0;
                skb = skb2;
        }
#endif

#if DUMP_PACKETS > 0
        printk("%s: send datalen:%ld lecid:%4.4x\n", dev->name,
               skb->len, priv->lecid);
#if DUMP_PACKETS >= 2
        for(i=0;i<skb->len && i <99;i++) {
                sprintf(buf+i*3,"%2.2x ",0xff&skb->data[i]);
        }
#elif DUMP_PACKETS >= 1
        for(i=0;i<skb->len && i < 30;i++) {
                sprintf(buf+i*3,"%2.2x ", 0xff&skb->data[i]);
        }
#endif /* DUMP_PACKETS >= 1 */
        if (i==skb->len)
                printk("%s\n",buf);
        else
                printk("%s...\n",buf);
#endif /* DUMP_PACKETS > 0 */

        /* 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) {
                                priv->stats.tx_dropped++;
                                return 0;
                        }
                        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);
        DPRINTK("%s:vcc:%p vcc_flags:%x, entry:%p\n", 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)) {
                        DPRINTK("%s:lec_start_xmit: queuing packet, ", dev->name);
                        DPRINTK("MAC address 0x%02x:%02x:%02x:%02x:%02x:%02x\n",
                                lec_h->h_dest[0], lec_h->h_dest[1], lec_h->h_dest[2],
                                lec_h->h_dest[3], lec_h->h_dest[4], lec_h->h_dest[5]);
                        skb_queue_tail(&entry->tx_wait, skb);
                } else {
                        DPRINTK("%s:lec_start_xmit: tx queue full or no arp entry, dropping, ", dev->name);
                        DPRINTK("MAC address 0x%02x:%02x:%02x:%02x:%02x:%02x\n",
                                lec_h->h_dest[0], lec_h->h_dest[1], lec_h->h_dest[2],
                                lec_h->h_dest[3], lec_h->h_dest[4], lec_h->h_dest[5]);
                        priv->stats.tx_dropped++;
                        dev_kfree_skb(skb);
                }
                return 0;
        }
                
#if DUMP_PACKETS > 0                    
        printk("%s:sending to vpi:%d vci:%d\n", dev->name,
               vcc->vpi, vcc->vci);       
#endif /* DUMP_PACKETS > 0 */
                
        while (entry && (skb2 = skb_dequeue(&entry->tx_wait))) {
                DPRINTK("lec.c: emptying tx queue, ");
                DPRINTK("MAC address 0x%02x:%02x:%02x:%02x:%02x:%02x\n",
                        lec_h->h_dest[0], lec_h->h_dest[1], lec_h->h_dest[2],
                        lec_h->h_dest[3], lec_h->h_dest[4], lec_h->h_dest[5]);
		lec_send(vcc, skb2, priv);
        }

	lec_send(vcc, skb, priv);

	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);
	}

	dev->trans_start = jiffies;
        return 0;
}

/* The inverse routine to net_open(). */
static int 
lec_close(struct net_device *dev) 
{
        netif_stop_queue(dev);
        return 0;
}

/*
 * Get the current statistics.
 * This may be called with the card open or closed.
 */
static struct net_device_stats *
lec_get_stats(struct net_device *dev)
{
        return &((struct lec_priv *)dev->priv)->stats;
}

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 = (struct lec_priv*)dev->priv;
        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);
        DPRINTK("%s: msg from zeppelin:%d\n", 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);
                DPRINTK("lec: in l_arp_update\n");
                if (mesg->sizeoftlvs != 0) { /* LANE2 3.1.5 */
                        DPRINTK("lec: LANE2 3.1.5, got tlvs, size %d\n", 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->change_mtu(dev, mesg->content.config.mtu))
			printk("%s: change_mtu to %d failed\n", 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)
                struct net_bridge_fdb_entry *f;

                DPRINTK("%s: bridge zeppelin asks about 0x%02x:%02x:%02x:%02x:%02x:%02x\n",
                        dev->name,
                        mesg->content.proxy.mac_addr[0], mesg->content.proxy.mac_addr[1],
                        mesg->content.proxy.mac_addr[2], mesg->content.proxy.mac_addr[3],
                        mesg->content.proxy.mac_addr[4], mesg->content.proxy.mac_addr[5]);

                if (br_fdb_get_hook == NULL || dev->br_port == NULL)
                        break;

                f = br_fdb_get_hook(dev->br_port->br, mesg->content.proxy.mac_addr);
                if (f != NULL &&
                    f->dst->dev != dev &&
                    f->dst->state == BR_STATE_FORWARDING) {
                                /* hit from bridge table, send LE_ARP_RESPONSE */
                        struct sk_buff *skb2;
			struct sock *sk;

                        DPRINTK("%s: entry found, responding to zeppelin\n", dev->name);
                        skb2 = alloc_skb(sizeof(struct atmlec_msg), GFP_ATOMIC);
                        if (skb2 == NULL) {
                                br_fdb_put_hook(f);
                                break;
                        }
                        skb2->len = sizeof(struct atmlec_msg);
                        memcpy(skb2->data, mesg, sizeof(struct atmlec_msg));
                        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);
                }
                if (f != NULL) br_fdb_put_hook(f);
#endif /* defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE) */
                }
                break;
        default:
                printk("%s: Unknown message type %d\n", 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 = (struct lec_priv *)dev->priv;

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

        netif_stop_queue(dev);
        lec_arp_destroy(priv);

        if (skb_peek(&sk_atm(vcc)->sk_receive_queue))
		printk("%s lec_atm_close: closing with messages pending\n",
                       dev->name);
        while ((skb = skb_dequeue(&sk_atm(vcc)->sk_receive_queue)) != NULL) {
                atm_return(vcc, skb->truesize);
		dev_kfree_skb(skb);
        }
  
	printk("%s: Shut down!\n", 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
};

/*
 * 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, 
             unsigned char *mac_addr, 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) {
                DPRINTK("lec: about to send %d bytes of data\n", 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
         */
        return;
}

static void 
lec_init(struct net_device *dev)
{
        dev->change_mtu = lec_change_mtu;
        dev->open = lec_open;
        dev->stop = lec_close;
        dev->hard_start_xmit = lec_start_xmit;
	dev->tx_timeout = lec_tx_timeout;

        dev->get_stats = lec_get_stats;
        dev->set_multicast_list = lec_set_multicast_list;
        dev->do_ioctl  = NULL;
        printk("%s: Initialized!\n",dev->name);
        return;
}

static 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 = (struct lec_priv *)dev->priv; 

#if DUMP_PACKETS >0
        int i=0;
        char buf[300];

        printk("%s: lec_push vcc vpi:%d vci:%d\n", dev->name,
               vcc->vpi, vcc->vci);
#endif
        if (!skb) {
                DPRINTK("%s: null skb\n",dev->name);
                lec_vcc_close(priv, vcc);
                return;
        }
#if DUMP_PACKETS > 0
        printk("%s: rcv datalen:%ld lecid:%4.4x\n", dev->name,
               skb->len, priv->lecid);
#if DUMP_PACKETS >= 2
        for(i=0;i<skb->len && i <99;i++) {
                sprintf(buf+i*3,"%2.2x ",0xff&skb->data[i]);
        }
#elif DUMP_PACKETS >= 1
        for(i=0;i<skb->len && i < 30;i++) {
                sprintf(buf+i*3,"%2.2x ", 0xff&skb->data[i]);
        }
#endif /* DUMP_PACKETS >= 1 */
        if (i==skb->len)
                printk("%s\n",buf);
        else
                printk("%s...\n",buf);
#endif /* DUMP_PACKETS > 0 */
        if (memcmp(skb->data, lec_ctrl_magic, 4) ==0) { /* Control frame, to daemon*/
		struct sock *sk = sk_atm(vcc);

                DPRINTK("%s: To daemon\n",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 (*(uint16_t *)skb->data == htons(priv->lecid) ||
                    !priv->lecd ||
                    !(dev->flags & IFF_UP)) { 
                        /* Probably looping back, or if lecd is missing,
                           lecd has gone down */
                        DPRINTK("Ignoring frame...\n");
                        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);
				kfree(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 (priv->lec_arp_empty_ones) {
                        lec_arp_check_empties(priv, vcc, skb);
                }
                skb->dev = dev;
                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);
                priv->stats.rx_packets++;
                priv->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) {
		printk("lec_pop(): vpriv = NULL!?!?!?\n");
		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) {
                printk("lec: lec_vcc_attach, copy from user failed for %d bytes\n",
                       bytes_left);
        }
        if (ioc_data.dev_num < 0 || ioc_data.dev_num >= MAX_LEC_ITF || 
            !dev_lec[ioc_data.dev_num])
                return -EINVAL;
	if (!(vpriv = kmalloc(sizeof(struct lec_vcc_priv), GFP_KERNEL)))
		return -ENOMEM;
	vpriv->xoff = 0;
	vpriv->old_pop = vcc->pop;
	vcc->user_back = vpriv;
	vcc->pop = lec_pop;
        lec_vcc_added(dev_lec[ioc_data.dev_num]->priv, 
                      &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((struct lec_priv*)dev_lec[arg]->priv, 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;
                snprintf(dev_lec[i]->name, IFNAMSIZ, "lec%d", i);
                if (register_netdev(dev_lec[i])) {
                        free_netdev(dev_lec[i]);
                        return -EINVAL;
                }

                priv = dev_lec[i]->priv;
                priv->is_trdev = is_trdev;
                lec_init(dev_lec[i]);
        } else {
                priv = dev_lec[i]->priv;
                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 char* lec_arp_get_status_string(unsigned char status)
{
	static char *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, '\n');
}


struct lec_state {
	unsigned long flags;
	struct lec_priv *locked;
	struct lec_arp_table *entry;
	struct net_device *dev;
	int itf;
	int arp_table;
	int misc_table;
};

static void *lec_tbl_walk(struct lec_state *state, struct lec_arp_table *tbl,
			  loff_t *l)
{
	struct lec_arp_table *e = state->entry;

	if (!e)
		e = tbl;
	if (e == (void *)1) {
		e = tbl;
		--*l;
	}
	for (; e; e = e->next) {
		if (--*l < 0)