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

#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 <asm/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 <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"

#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 void lec_init(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)
{
        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 = 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);
        }

        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;
        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);
        memset(&dev->stats, 0, sizeof(struct net_device_stats));

        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)
{
        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 = 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;
#if DUMP_PACKETS > 0
        char buf[300];
        int i = 0;
#endif /* DUMP_PACKETS >0 */

        pr_debug("lec_start_xmit called\n");
        if (!priv->lecd) {
                printk("%s:No lecd attached\n", dev->name);
                dev->stats.tx_errors++;
                netif_stop_queue(dev);
                return -EUNATCH;
        }

        pr_debug("skbuff head:%lx data:%lx tail:%lx end:%lx\n",
                (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("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) {
                                dev->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);
        pr_debug("%s:vcc:%p vcc_flags:%lx, 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)) {
                        pr_debug("%s:lec_start_xmit: queuing packet, ",
                                dev->name);
                        pr_debug("MAC address %pM\n", lec_h->h_dest);
                        skb_queue_tail(&entry->tx_wait, skb);
                } else {
                        pr_debug
                            ("%s:lec_start_xmit: tx queue full or no arp entry, dropping, ",
                             dev->name);
                        pr_debug("MAC address %pM\n", lec_h->h_dest);
                        dev->stats.tx_dropped++;
                        dev_kfree_skb(skb);
                }
                goto out;
        }
#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))) {
                pr_debug("lec.c: emptying tx queue, ");
                pr_debug("MAC address %pM\n", 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 0;
}

/* 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\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);
                pr_debug("lec: in l_arp_update\n");
                if (mesg->sizeoftlvs != 0) {    /* LANE2 3.1.5 */
                        pr_debug("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_set_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;

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

                        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;

                                pr_debug
                                    ("%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);
                                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);
                        }
                        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 = 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))
                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(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("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 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_multicast_list = lec_set_multicast_list,
};


static void lec_init(struct net_device *dev)
{
        dev->netdev_ops = &lec_netdev_ops;
        printk("%s: Initialized!\n", dev->name);
}

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
        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) {
                pr_debug("%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);

                pr_debug("%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 (*(__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...\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);
                                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) {
                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(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((struct lec_priv *)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;
                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;
                lec_init(dev_lec[i]);
        } 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 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 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 char lec_banner[] = "Itf  MAC          ATM destination"
            "                          Status            Flags "
            "VPI/VCI Recv VPI/VCI\n";

        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) {
                printk(KERN_ERR "Unable to initialize /proc/net/atm/lec\n");
                return -ENOMEM;
        }
#endif

        register_atm_ioctl(&lane_ioctl_ops);
        printk("lec.c: " __DATE__ " " __TIME__ " initialized\n");
        return 0;
}

static void __exit lane_module_cleanup(void)
{
        int i;
        struct lec_priv *priv;

        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) {
                        priv = netdev_priv(dev_lec[i]);
                        unregister_netdev(dev_lec[i]);
                        free_netdev(dev_lec[i]);
                        dev_lec[i] = NULL;
                }
        }

        return;
}

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)
                printk("lec.c: lane2_associate_req() failed\n");
        /*
         * 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
        printk("lec.c: lane2_associate_ind()\n");
        printk("dump of tlvs, sizeoftlvs=%d\n", sizeoftlvs);
        while (i < sizeoftlvs)
                printk("%02x ", tlvs[i++]);

        printk("\n");
#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);
        }
        return;
}

/*
 * 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 <asm/param.h>
#include <asm/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("LEC_ARP: Added entry:%2.2x %2.2x %2.2x %2.2x %2.2x %2.2x\n",
                0xff & entry->mac_addr[0], 0xff & entry->mac_addr[1],
                0xff & entry->mac_addr[2], 0xff & entry->mac_addr[3],
                0xff & entry->mac_addr[4], 0xff & entry->mac_addr[5]);
}

/*
 * 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("LEC_ARP: Removed entry:%2.2x %2.2x %2.2x %2.2x %2.2x %2.2x\n",
                0xff & to_remove->mac_addr[0], 0xff & to_remove->mac_addr[1],
                0xff & to_remove->mac_addr[2], 0xff & to_remove->mac_addr[3],
                0xff & to_remove->mac_addr[4], 0xff & to_remove->mac_addr[5]);
        return 0;
}

#if DEBUG_ARP_TABLE
static 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";
        default:
                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;

        printk("Dump %p:\n", 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\n", i, rulla);
                        offset += sprintf(buf + offset, "Mac:");
                        for (j = 0; j < ETH_ALEN; j++) {
                                offset += sprintf(buf + offset,
                                                  "%2.2x ",
                                                  rulla->mac_addr[j] & 0xff);
                        }
                        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));
                        printk("%s\n", buf);
                }
        }

        if (!hlist_empty(&priv->lec_no_forward))
                printk("No forward\n");
        hlist_for_each_entry(rulla, node, &priv->lec_no_forward, next) {
                offset = 0;
                offset += sprintf(buf + offset, "Mac:");
                for (j = 0; j < ETH_ALEN; j++) {
                        offset += sprintf(buf + offset, "%2.2x ",
                                          rulla->mac_addr[j] & 0xff);
                }
                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));
                printk("%s\n", buf);
        }

        if (!hlist_empty(&priv->lec_arp_empty_ones))
                printk("Empty ones\n");
        hlist_for_each_entry(rulla, node, &priv->lec_arp_empty_ones, next) {
                offset = 0;
                offset += sprintf(buf + offset, "Mac:");
                for (j = 0; j < ETH_ALEN; j++) {
                        offset += sprintf(buf + offset, "%2.2x ",
                                          rulla->mac_addr[j] & 0xff);
                }
                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));
                printk("%s", buf);
        }

        if (!hlist_empty(&priv->mcast_fwds))
                printk("Multicast Forward VCCs\n");
        hlist_for_each_entry(rulla, node, &priv->mcast_fwds, next) {
                offset = 0;
                offset += sprintf(buf + offset, "Mac:");
                for (j = 0; j < ETH_ALEN; j++) {
                        offset += sprintf(buf + offset, "%2.2x ",
                                          rulla->mac_addr[j] & 0xff);
                }
                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));
                printk("%s\n", 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_rearming_delayed_work(&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;
        spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
}

/*
 * Find entry by mac_address
 */
static struct lec_arp_table *lec_arp_find(struct lec_priv *priv,
                                          const unsigned char *mac_addr)
{
        struct hlist_node *node;
        struct hlist_head *head;
        struct lec_arp_table *entry;

        pr_debug("LEC_ARP: lec_arp_find :%2.2x %2.2x %2.2x %2.2x %2.2x %2.2x\n",
                mac_addr[0] & 0xff, mac_addr[1] & 0xff, mac_addr[2] & 0xff,
                mac_addr[3] & 0xff, mac_addr[4] & 0xff, mac_addr[5] & 0xff);

        head = &priv->lec_arp_tables[HASH(mac_addr[ETH_ALEN - 1])];
        hlist_for_each_entry(entry, node, head, next) {
                if (!compare_ether_addr(mac_addr, entry->mac_addr)) {
                        return entry;
                }
        }
        return NULL;
}

static struct lec_arp_table *make_entry(struct lec_priv *priv,
                                        const unsigned char *mac_addr)
{
        struct lec_arp_table *to_return;

        to_return = kzalloc(sizeof(struct lec_arp_table), GFP_ATOMIC);
        if (!to_return) {
                printk("LEC: Arp entry kmalloc failed\n");
                return NULL;
        }
        memcpy(to_return->mac_addr, mac_addr, ETH_ALEN);
        INIT_HLIST_NODE(&to_return->next);
        setup_timer(&to_return->timer, lec_arp_expire_arp,
                        (unsigned long)to_return);
        to_return->last_used = jiffies;
        to_return->priv = priv;
        skb_queue_head_init(&to_return->tx_wait);
        atomic_set(&to_return->usage, 1);
        return to_return;
}

/* Arp sent timer expired */
static void lec_arp_expire_arp(unsigned long data)
{
        struct lec_arp_table *entry;

        entry = (struct lec_arp_table *)data;

        pr_debug("lec_arp_expire_arp\n");
        if (entry->status == ESI_ARP_PENDING) {
                if (entry->no_tries <= entry->priv->max_retry_count) {
                        if (entry->is_rdesc)
                                send_to_lecd(entry->priv, l_rdesc_arp_xmt,
                                             entry->mac_addr, NULL, NULL);
                        else
                                send_to_lecd(entry->priv, l_arp_xmt,
                                             entry->mac_addr, NULL, NULL);
                        entry->no_tries++;
                }
                mod_timer(&entry->timer, jiffies + (1 * HZ));
        }
}

/* Unknown/unused vcc expire, remove associated entry */
static void lec_arp_expire_vcc(unsigned long data)
{
        unsigned long flags;
        struct lec_arp_table *to_remove = (struct lec_arp_table *)data;
        struct lec_priv *priv = (struct lec_priv *)to_remove->priv;

        del_timer(&to_remove->timer);

        pr_debug("LEC_ARP %p %p: lec_arp_expire_vcc vpi:%d vci:%d\n",
                to_remove, priv,
                to_remove->vcc ? to_remove->recv_vcc->vpi : 0,
                to_remove->vcc ? to_remove->recv_vcc->vci : 0);

        spin_lock_irqsave(&priv->lec_arp_lock, flags);
        hlist_del(&to_remove->next);
        spin_unlock_irqrestore(&priv->lec_arp_lock, flags);

        lec_arp_clear_vccs(to_remove);
        lec_arp_put(to_remove);
}

/*
 * Expire entries.
 * 1. Re-set timer
 * 2. For each entry, delete entries that have aged past the age limit.
 * 3. For each entry, depending on the status of the entry, perform
 *    the following maintenance.
 *    a. If status is ESI_VC_PENDING or ESI_ARP_PENDING then if the
 *       tick_count is above the max_unknown_frame_time, clear
 *       the tick_count to zero and clear the packets_flooded counter
 *       to zero. This supports the packet rate limit per address
 *       while flooding unknowns.
 *    b. If the status is ESI_FLUSH_PENDING and the tick_count is greater
 *       than or equal to the path_switching_delay, change the status
 *       to ESI_FORWARD_DIRECT. This causes the flush period to end
 *       regardless of the progress of the flush protocol.
 */
static void lec_arp_check_expire(struct work_struct *work)
{
        unsigned long flags;
        struct lec_priv *priv =
                container_of(work, struct lec_priv, lec_arp_work.work);
        struct hlist_node *node, *next;
        struct lec_arp_table *entry;
        unsigned long now;
        unsigned long time_to_check;
        int i;

        pr_debug("lec_arp_check_expire %p\n", priv);
        now = jiffies;
restart:
        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) {
                        if ((entry->flags) & LEC_REMOTE_FLAG &&
                            priv->topology_change)
                                time_to_check = priv->forward_delay_time;
                        else
                                time_to_check = priv->aging_time;

                        pr_debug("About to expire: %lx - %lx > %lx\n",
                                now, entry->last_used, time_to_check);
                        if (time_after(now, entry->last_used + time_to_check)
                            && !(entry->flags & LEC_PERMANENT_FLAG)
                            && !(entry->mac_addr[0] & 0x01)) {  /* LANE2: 7.1.20 */
                                /* Remove entry */
                                pr_debug("LEC:Entry timed out\n");
                                lec_arp_remove(priv, entry);
                                lec_arp_put(entry);
                        } else {
                                /* Something else */
                                if ((entry->status == ESI_VC_PENDING ||
                                     entry->status == ESI_ARP_PENDING)
                                    && time_after_eq(now,
                                                     entry->timestamp +
                                                     priv->
                                                     max_unknown_frame_time)) {
                                        entry->timestamp = jiffies;
                                        entry->packets_flooded = 0;
                                        if (entry->status == ESI_VC_PENDING)
                                                send_to_lecd(priv, l_svc_setup,
                                                             entry->mac_addr,
                                                             entry->atm_addr,
                                                             NULL);
                                }
                                if (entry->status == ESI_FLUSH_PENDING
                                    &&
                                    time_after_eq(now, entry->timestamp +
                                                  priv->path_switching_delay)) {
                                        struct sk_buff *skb;
                                        struct atm_vcc *vcc = entry->vcc;

                                        lec_arp_hold(entry);
                                        spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
                                        while ((skb = skb_dequeue(&entry->tx_wait)) != NULL)
                                                lec_send(vcc, skb);
                                        entry->last_used = jiffies;
                                        entry->status = ESI_FORWARD_DIRECT;
                                        lec_arp_put(entry);
                                        goto restart;
                                }
                        }
                }
        }
        spin_unlock_irqrestore(&priv->lec_arp_lock, flags);

        schedule_delayed_work(&priv->lec_arp_work, LEC_ARP_REFRESH_INTERVAL);
}

/*
 * Try to find vcc where mac_address is attached.
 *
 */
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)
{
        unsigned long flags;
        struct lec_arp_table *entry;
        struct atm_vcc *found;

        if (mac_to_find[0] & 0x01) {
                switch (priv->lane_version) {
                case 1:
                        return priv->mcast_vcc;
                case 2: /* LANE2 wants arp for multicast addresses */
                        if (!compare_ether_addr(mac_to_find, bus_mac))
                                return priv->mcast_vcc;
                        break;
                default:
                        break;
                }
        }

        spin_lock_irqsave(&priv->lec_arp_lock, flags);
        entry = lec_arp_find(priv, mac_to_find);

        if (entry) {
                if (entry->status == ESI_FORWARD_DIRECT) {
                        /* Connection Ok */
                        entry->last_used = jiffies;
                        lec_arp_hold(entry);
                        *ret_entry = entry;
                        found = entry->vcc;
                        goto out;
                }
                /*
                 * If the LE_ARP cache entry is still pending, reset count to 0
                 * so another LE_ARP request can be made for this frame.
                 */
                if (entry->status == ESI_ARP_PENDING) {
                        entry->no_tries = 0;
                }
                /*
                 * Data direct VC not yet set up, check to see if the unknown
                 * frame count is greater than the limit. If the limit has
                 * not been reached, allow the caller to send packet to
                 * BUS.
                 */
                if (entry->status != ESI_FLUSH_PENDING &&
                    entry->packets_flooded <
                    priv->maximum_unknown_frame_count) {
                        entry->packets_flooded++;
                        pr_debug("LEC_ARP: Flooding..\n");
                        found = priv->mcast_vcc;
                        goto out;
                }
                /*
                 * We got here because entry->status == ESI_FLUSH_PENDING
                 * or BUS flood limit was reached for an entry which is
                 * in ESI_ARP_PENDING or ESI_VC_PENDING state.
                 */
                lec_arp_hold(entry);
                *ret_entry = entry;
                pr_debug("lec: entry->status %d entry->vcc %p\n", entry->status,
                        entry->vcc);
                found = NULL;
        } else {
                /* No matching entry was found */
                entry = make_entry(priv, mac_to_find);
                pr_debug("LEC_ARP: Making entry\n");
                if (!entry) {
                        found = priv->mcast_vcc;
                        goto out;
                }
                lec_arp_add(priv, entry);
                /* We want arp-request(s) to be sent */
                entry->packets_flooded = 1;
                entry->status = ESI_ARP_PENDING;
                entry->no_tries = 1;
                entry->last_used = entry->timestamp = jiffies;
                entry->is_rdesc = is_rdesc;
                if (entry->is_rdesc)
                        send_to_lecd(priv, l_rdesc_arp_xmt, mac_to_find, NULL,
                                     NULL);
                else
                        send_to_lecd(priv, l_arp_xmt, mac_to_find, NULL, NULL);
                entry->timer.expires = jiffies + (1 * HZ);
                entry->timer.function = lec_arp_expire_arp;
                add_timer(&entry->timer);
                found = priv->mcast_vcc;
        }

out:
        spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
        return found;
}

static int
lec_addr_delete(struct lec_priv *priv, const unsigned char *atm_addr,
                unsigned long permanent)
{
        unsigned long flags;
        struct hlist_node *node, *next;