Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1045 insertions, 0 deletions

diff --git a/net/atm/clip.c b/net/atm/clip.c
new file mode 100644
index 000000000000..28dab55a4387
--- /dev/null
+++ b/net/atm/clip.c
@@ -0,0 +1,1045 @@
+/* net/atm/clip.c - RFC1577 Classical IP over ATM */
+
+/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
+
+
+#include <linux/config.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/kernel.h> /* for UINT_MAX */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/wait.h>
+#include <linux/timer.h>
+#include <linux/if_arp.h> /* for some manifest constants */
+#include <linux/notifier.h>
+#include <linux/atm.h>
+#include <linux/atmdev.h>
+#include <linux/atmclip.h>
+#include <linux/atmarp.h>
+#include <linux/ip.h> /* for net/route.h */
+#include <linux/in.h> /* for struct sockaddr_in */
+#include <linux/if.h> /* for IFF_UP */
+#include <linux/inetdevice.h>
+#include <linux/bitops.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/rcupdate.h>
+#include <linux/jhash.h>
+#include <net/route.h> /* for struct rtable and routing */
+#include <net/icmp.h> /* icmp_send */
+#include <asm/param.h> /* for HZ */
+#include <asm/byteorder.h> /* for htons etc. */
+#include <asm/system.h> /* save/restore_flags */
+#include <asm/uaccess.h>
+#include <asm/atomic.h>
+
+#include "common.h"
+#include "resources.h"
+#include "ipcommon.h"
+#include <net/atmclip.h>
+
+
+#if 0
+#define DPRINTK(format,args...) printk(format,##args)
+#else
+#define DPRINTK(format,args...)
+#endif
+
+
+static struct net_device *clip_devs;
+static struct atm_vcc *atmarpd;
+static struct neigh_table clip_tbl;
+static struct timer_list idle_timer;
+static int start_timer = 1;
+
+
+static int to_atmarpd(enum atmarp_ctrl_type type,int itf,unsigned long ip)
+{
+        struct sock *sk;
+        struct atmarp_ctrl *ctrl;
+        struct sk_buff *skb;
+
+        DPRINTK("to_atmarpd(%d)\n",type);
+        if (!atmarpd) return -EUNATCH;
+        skb = alloc_skb(sizeof(struct atmarp_ctrl),GFP_ATOMIC);
+        if (!skb) return -ENOMEM;
+        ctrl = (struct atmarp_ctrl *) skb_put(skb,sizeof(struct atmarp_ctrl));
+        ctrl->type = type;
+        ctrl->itf_num = itf;
+        ctrl->ip = ip;
+        atm_force_charge(atmarpd,skb->truesize);
+
+        sk = sk_atm(atmarpd);
+        skb_queue_tail(&sk->sk_receive_queue, skb);
+        sk->sk_data_ready(sk, skb->len);
+        return 0;
+}
+
+
+static void link_vcc(struct clip_vcc *clip_vcc,struct atmarp_entry *entry)
+{
+        DPRINTK("link_vcc %p to entry %p (neigh %p)\n",clip_vcc,entry,
+            entry->neigh);
+        clip_vcc->entry = entry;
+        clip_vcc->xoff = 0; /* @@@ may overrun buffer by one packet */
+        clip_vcc->next = entry->vccs;
+        entry->vccs = clip_vcc;
+        entry->neigh->used = jiffies;
+}
+
+
+static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
+{
+        struct atmarp_entry *entry = clip_vcc->entry;
+        struct clip_vcc **walk;
+
+        if (!entry) {
+                printk(KERN_CRIT "!clip_vcc->entry (clip_vcc %p)\n",clip_vcc);
+                return;
+        }
+        spin_lock_bh(&entry->neigh->dev->xmit_lock);    /* block clip_start_xmit() */
+        entry->neigh->used = jiffies;
+        for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
+                if (*walk == clip_vcc) {
+                        int error;
+
+                        *walk = clip_vcc->next; /* atomic */
+                        clip_vcc->entry = NULL;
+                        if (clip_vcc->xoff)
+                                netif_wake_queue(entry->neigh->dev);
+                        if (entry->vccs)
+                                goto out;
+                        entry->expires = jiffies-1;
+                                /* force resolution or expiration */
+                        error = neigh_update(entry->neigh, NULL, NUD_NONE,
+                                             NEIGH_UPDATE_F_ADMIN);
+                        if (error)
+                                printk(KERN_CRIT "unlink_clip_vcc: "
+                                    "neigh_update failed with %d\n",error);
+                        goto out;
+                }
+        printk(KERN_CRIT "ATMARP: unlink_clip_vcc failed (entry %p, vcc "
+          "0x%p)\n",entry,clip_vcc);
+out:
+        spin_unlock_bh(&entry->neigh->dev->xmit_lock);
+}
+
+/* The neighbour entry n->lock is held. */
+static int neigh_check_cb(struct neighbour *n)
+{
+        struct atmarp_entry *entry = NEIGH2ENTRY(n);
+        struct clip_vcc *cv;
+
+        for (cv = entry->vccs; cv; cv = cv->next) {
+                unsigned long exp = cv->last_use + cv->idle_timeout;
+
+                if (cv->idle_timeout && time_after(jiffies, exp)) {
+                        DPRINTK("releasing vcc %p->%p of entry %p\n",
+                                cv, cv->vcc, entry);
+                        vcc_release_async(cv->vcc, -ETIMEDOUT);
+                }
+        }
+
+        if (entry->vccs || time_before(jiffies, entry->expires))
+                return 0;
+
+        if (atomic_read(&n->refcnt) > 1) {
+                struct sk_buff *skb;
+
+                DPRINTK("destruction postponed with ref %d\n",
+                        atomic_read(&n->refcnt));
+
+                while ((skb = skb_dequeue(&n->arp_queue)) != NULL) 
+                        dev_kfree_skb(skb);
+
+                return 0;
+        }
+
+        DPRINTK("expired neigh %p\n",n);
+        return 1;
+}
+
+static void idle_timer_check(unsigned long dummy)
+{
+        write_lock(&clip_tbl.lock);
+        __neigh_for_each_release(&clip_tbl, neigh_check_cb);
+        mod_timer(&idle_timer, jiffies+CLIP_CHECK_INTERVAL*HZ);
+        write_unlock(&clip_tbl.lock);
+}
+
+static int clip_arp_rcv(struct sk_buff *skb)
+{
+        struct atm_vcc *vcc;
+
+        DPRINTK("clip_arp_rcv\n");
+        vcc = ATM_SKB(skb)->vcc;
+        if (!vcc || !atm_charge(vcc,skb->truesize)) {
+                dev_kfree_skb_any(skb);
+                return 0;
+        }
+        DPRINTK("pushing to %p\n",vcc);
+        DPRINTK("using %p\n",CLIP_VCC(vcc)->old_push);
+        CLIP_VCC(vcc)->old_push(vcc,skb);
+        return 0;
+}
+
+static const unsigned char llc_oui[] = {
+        0xaa,   /* DSAP: non-ISO */
+        0xaa,   /* SSAP: non-ISO */
+        0x03,   /* Ctrl: Unnumbered Information Command PDU */
+        0x00,   /* OUI: EtherType */
+        0x00,
+        0x00 };
+
+static void clip_push(struct atm_vcc *vcc,struct sk_buff *skb)
+{
+        struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
+
+        DPRINTK("clip push\n");
+        if (!skb) {
+                DPRINTK("removing VCC %p\n",clip_vcc);
+                if (clip_vcc->entry) unlink_clip_vcc(clip_vcc);
+                clip_vcc->old_push(vcc,NULL); /* pass on the bad news */
+                kfree(clip_vcc);
+                return;
+        }
+        atm_return(vcc,skb->truesize);
+        skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs;
+                /* clip_vcc->entry == NULL if we don't have an IP address yet */
+        if (!skb->dev) {
+                dev_kfree_skb_any(skb);
+                return;
+        }
+        ATM_SKB(skb)->vcc = vcc;
+        skb->mac.raw = skb->data;
+        if (!clip_vcc->encap || skb->len < RFC1483LLC_LEN || memcmp(skb->data,
+            llc_oui,sizeof(llc_oui))) skb->protocol = htons(ETH_P_IP);
+        else {
+                skb->protocol = ((u16 *) skb->data)[3];
+                skb_pull(skb,RFC1483LLC_LEN);
+                if (skb->protocol == htons(ETH_P_ARP)) {
+                        PRIV(skb->dev)->stats.rx_packets++;
+                        PRIV(skb->dev)->stats.rx_bytes += skb->len;
+                        clip_arp_rcv(skb);
+                        return;
+                }
+        }
+        clip_vcc->last_use = jiffies;
+        PRIV(skb->dev)->stats.rx_packets++;
+        PRIV(skb->dev)->stats.rx_bytes += skb->len;
+        memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
+        netif_rx(skb);
+}
+
+
+/*
+ * Note: these spinlocks _must_not_ block on non-SMP. The only goal is that
+ * clip_pop is atomic with respect to the critical section in clip_start_xmit.
+ */
+
+
+static void clip_pop(struct atm_vcc *vcc,struct sk_buff *skb)
+{
+        struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
+        struct net_device *dev = skb->dev;
+        int old;
+        unsigned long flags;
+
+        DPRINTK("clip_pop(vcc %p)\n",vcc);
+        clip_vcc->old_pop(vcc,skb);
+        /* skb->dev == NULL in outbound ARP packets */
+        if (!dev) return;
+        spin_lock_irqsave(&PRIV(dev)->xoff_lock,flags);
+        if (atm_may_send(vcc,0)) {
+                old = xchg(&clip_vcc->xoff,0);
+                if (old) netif_wake_queue(dev);
+        }
+        spin_unlock_irqrestore(&PRIV(dev)->xoff_lock,flags);
+}
+
+
+static void clip_neigh_destroy(struct neighbour *neigh)
+{
+        DPRINTK("clip_neigh_destroy (neigh %p)\n",neigh);
+        if (NEIGH2ENTRY(neigh)->vccs)
+                printk(KERN_CRIT "clip_neigh_destroy: vccs != NULL !!!\n");
+        NEIGH2ENTRY(neigh)->vccs = (void *) 0xdeadbeef;
+}
+
+
+static void clip_neigh_solicit(struct neighbour *neigh,struct sk_buff *skb)
+{
+        DPRINTK("clip_neigh_solicit (neigh %p, skb %p)\n",neigh,skb);
+        to_atmarpd(act_need,PRIV(neigh->dev)->number,NEIGH2ENTRY(neigh)->ip);
+}
+
+
+static void clip_neigh_error(struct neighbour *neigh,struct sk_buff *skb)
+{
+#ifndef CONFIG_ATM_CLIP_NO_ICMP
+        icmp_send(skb,ICMP_DEST_UNREACH,ICMP_HOST_UNREACH,0);
+#endif
+        kfree_skb(skb);
+}
+
+
+static struct neigh_ops clip_neigh_ops = {
+        .family =               AF_INET,
+        .destructor =           clip_neigh_destroy,
+        .solicit =              clip_neigh_solicit,
+        .error_report =         clip_neigh_error,
+        .output =               dev_queue_xmit,
+        .connected_output =     dev_queue_xmit,
+        .hh_output =            dev_queue_xmit,
+        .queue_xmit =           dev_queue_xmit,
+};
+
+
+static int clip_constructor(struct neighbour *neigh)
+{
+        struct atmarp_entry *entry = NEIGH2ENTRY(neigh);
+        struct net_device *dev = neigh->dev;
+        struct in_device *in_dev;
+        struct neigh_parms *parms;
+
+        DPRINTK("clip_constructor (neigh %p, entry %p)\n",neigh,entry);
+        neigh->type = inet_addr_type(entry->ip);
+        if (neigh->type != RTN_UNICAST) return -EINVAL;
+
+        rcu_read_lock();
+        in_dev = rcu_dereference(__in_dev_get(dev));
+        if (!in_dev) {
+                rcu_read_unlock();
+                return -EINVAL;
+        }
+
+        parms = in_dev->arp_parms;
+        __neigh_parms_put(neigh->parms);
+        neigh->parms = neigh_parms_clone(parms);
+        rcu_read_unlock();
+
+        neigh->ops = &clip_neigh_ops;
+        neigh->output = neigh->nud_state & NUD_VALID ?
+            neigh->ops->connected_output : neigh->ops->output;
+        entry->neigh = neigh;
+        entry->vccs = NULL;
+        entry->expires = jiffies-1;
+        return 0;
+}
+
+static u32 clip_hash(const void *pkey, const struct net_device *dev)
+{
+        return jhash_2words(*(u32 *)pkey, dev->ifindex, clip_tbl.hash_rnd);
+}
+
+static struct neigh_table clip_tbl = {
+        .family         = AF_INET,
+        .entry_size     = sizeof(struct neighbour)+sizeof(struct atmarp_entry),
+        .key_len        = 4,
+        .hash           = clip_hash,
+        .constructor    = clip_constructor,
+        .id             = "clip_arp_cache",
+
+        /* parameters are copied from ARP ... */
+        .parms = {
+                .tbl                    = &clip_tbl,
+                .base_reachable_time    = 30 * HZ,
+                .retrans_time           = 1 * HZ,
+                .gc_staletime           = 60 * HZ,
+                .reachable_time         = 30 * HZ,
+                .delay_probe_time       = 5 * HZ,
+                .queue_len              = 3,
+                .ucast_probes           = 3,
+                .mcast_probes           = 3,
+                .anycast_delay          = 1 * HZ,
+                .proxy_delay            = (8 * HZ) / 10,
+                .proxy_qlen             = 64,
+                .locktime               = 1 * HZ,
+        },
+        .gc_interval    = 30 * HZ,
+        .gc_thresh1     = 128,
+        .gc_thresh2     = 512,
+        .gc_thresh3     = 1024,
+};
+
+
+/* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
+
+/*
+ * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
+ * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
+ * don't increment the usage count. This is used to create entries in
+ * clip_setentry.
+ */
+
+
+static int clip_encap(struct atm_vcc *vcc,int mode)
+{
+        CLIP_VCC(vcc)->encap = mode;
+        return 0;
+}
+
+
+static int clip_start_xmit(struct sk_buff *skb,struct net_device *dev)
+{
+        struct clip_priv *clip_priv = PRIV(dev);
+        struct atmarp_entry *entry;
+        struct atm_vcc *vcc;
+        int old;
+        unsigned long flags;
+
+        DPRINTK("clip_start_xmit (skb %p)\n",skb);
+        if (!skb->dst) {
+                printk(KERN_ERR "clip_start_xmit: skb->dst == NULL\n");
+                dev_kfree_skb(skb);
+                clip_priv->stats.tx_dropped++;
+                return 0;
+        }
+        if (!skb->dst->neighbour) {
+#if 0
+                skb->dst->neighbour = clip_find_neighbour(skb->dst,1);
+                if (!skb->dst->neighbour) {
+                        dev_kfree_skb(skb); /* lost that one */
+                        clip_priv->stats.tx_dropped++;
+                        return 0;
+                }
+#endif
+                printk(KERN_ERR "clip_start_xmit: NO NEIGHBOUR !\n");
+                dev_kfree_skb(skb);
+                clip_priv->stats.tx_dropped++;
+                return 0;
+        }
+        entry = NEIGH2ENTRY(skb->dst->neighbour);
+        if (!entry->vccs) {
+                if (time_after(jiffies, entry->expires)) {
+                        /* should be resolved */
+                        entry->expires = jiffies+ATMARP_RETRY_DELAY*HZ;
+                        to_atmarpd(act_need,PRIV(dev)->number,entry->ip);
+                }
+                if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
+                        skb_queue_tail(&entry->neigh->arp_queue,skb);
+                else {
+                        dev_kfree_skb(skb);
+                        clip_priv->stats.tx_dropped++;
+                }
+                return 0;
+        }
+        DPRINTK("neigh %p, vccs %p\n",entry,entry->vccs);
+        ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
+        DPRINTK("using neighbour %p, vcc %p\n",skb->dst->neighbour,vcc);
+        if (entry->vccs->encap) {
+                void *here;
+
+                here = skb_push(skb,RFC1483LLC_LEN);
+                memcpy(here,llc_oui,sizeof(llc_oui));
+                ((u16 *) here)[3] = skb->protocol;
+        }
+        atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
+        ATM_SKB(skb)->atm_options = vcc->atm_options;
+        entry->vccs->last_use = jiffies;
+        DPRINTK("atm_skb(%p)->vcc(%p)->dev(%p)\n",skb,vcc,vcc->dev);
+        old = xchg(&entry->vccs->xoff,1); /* assume XOFF ... */
+        if (old) {
+                printk(KERN_WARNING "clip_start_xmit: XOFF->XOFF transition\n");
+                return 0;
+        }
+        clip_priv->stats.tx_packets++;
+        clip_priv->stats.tx_bytes += skb->len;
+        (void) vcc->send(vcc,skb);
+        if (atm_may_send(vcc,0)) {
+                entry->vccs->xoff = 0;
+                return 0;
+        }
+        spin_lock_irqsave(&clip_priv->xoff_lock,flags);
+        netif_stop_queue(dev); /* XOFF -> throttle immediately */
+        barrier();
+        if (!entry->vccs->xoff)
+                netif_start_queue(dev);
+                /* Oh, we just raced with clip_pop. netif_start_queue should be
+                   good enough, because nothing should really be asleep because
+                   of the brief netif_stop_queue. If this isn't true or if it
+                   changes, use netif_wake_queue instead. */
+        spin_unlock_irqrestore(&clip_priv->xoff_lock,flags);
+        return 0;
+}
+
+
+static struct net_device_stats *clip_get_stats(struct net_device *dev)
+{
+        return &PRIV(dev)->stats;
+}
+
+
+static int clip_mkip(struct atm_vcc *vcc,int timeout)
+{
+        struct clip_vcc *clip_vcc;
+        struct sk_buff_head copy;
+        struct sk_buff *skb;
+
+        if (!vcc->push) return -EBADFD;
+        clip_vcc = kmalloc(sizeof(struct clip_vcc),GFP_KERNEL);
+        if (!clip_vcc) return -ENOMEM;
+        DPRINTK("mkip clip_vcc %p vcc %p\n",clip_vcc,vcc);
+        clip_vcc->vcc = vcc;
+        vcc->user_back = clip_vcc;
+        set_bit(ATM_VF_IS_CLIP, &vcc->flags);
+        clip_vcc->entry = NULL;
+        clip_vcc->xoff = 0;
+        clip_vcc->encap = 1;
+        clip_vcc->last_use = jiffies;
+        clip_vcc->idle_timeout = timeout*HZ;
+        clip_vcc->old_push = vcc->push;
+        clip_vcc->old_pop = vcc->pop;
+        vcc->push = clip_push;
+        vcc->pop = clip_pop;
+        skb_queue_head_init(&copy);
+        skb_migrate(&sk_atm(vcc)->sk_receive_queue, &copy);
+        /* re-process everything received between connection setup and MKIP */
+        while ((skb = skb_dequeue(&copy)) != NULL)
+                if (!clip_devs) {
+                        atm_return(vcc,skb->truesize);
+                        kfree_skb(skb);
+                }
+                else {
+                        unsigned int len = skb->len;
+
+                        clip_push(vcc,skb);
+                        PRIV(skb->dev)->stats.rx_packets--;
+                        PRIV(skb->dev)->stats.rx_bytes -= len;
+                }
+        return 0;
+}
+
+
+static int clip_setentry(struct atm_vcc *vcc,u32 ip)
+{
+        struct neighbour *neigh;
+        struct atmarp_entry *entry;
+        int error;
+        struct clip_vcc *clip_vcc;
+        struct flowi fl = { .nl_u = { .ip4_u = { .daddr = ip, .tos = 1 } } };
+        struct rtable *rt;
+
+        if (vcc->push != clip_push) {
+                printk(KERN_WARNING "clip_setentry: non-CLIP VCC\n");
+                return -EBADF;
+        }
+        clip_vcc = CLIP_VCC(vcc);
+        if (!ip) {
+                if (!clip_vcc->entry) {
+                        printk(KERN_ERR "hiding hidden ATMARP entry\n");
+                        return 0;
+                }
+                DPRINTK("setentry: remove\n");
+                unlink_clip_vcc(clip_vcc);
+                return 0;
+        }
+        error = ip_route_output_key(&rt,&fl);
+        if (error) return error;
+        neigh = __neigh_lookup(&clip_tbl,&ip,rt->u.dst.dev,1);
+        ip_rt_put(rt);
+        if (!neigh)
+                return -ENOMEM;
+        entry = NEIGH2ENTRY(neigh);
+        if (entry != clip_vcc->entry) {
+                if (!clip_vcc->entry) DPRINTK("setentry: add\n");
+                else {
+                        DPRINTK("setentry: update\n");
+                        unlink_clip_vcc(clip_vcc);
+                }
+                link_vcc(clip_vcc,entry);
+        }
+        error = neigh_update(neigh, llc_oui, NUD_PERMANENT, 
+                             NEIGH_UPDATE_F_OVERRIDE|NEIGH_UPDATE_F_ADMIN);
+        neigh_release(neigh);
+        return error;
+}
+
+
+static void clip_setup(struct net_device *dev)
+{
+        dev->hard_start_xmit = clip_start_xmit;
+        /* sg_xmit ... */
+        dev->get_stats = clip_get_stats;
+        dev->type = ARPHRD_ATM;
+        dev->hard_header_len = RFC1483LLC_LEN;
+        dev->mtu = RFC1626_MTU;
+        dev->tx_queue_len = 100; /* "normal" queue (packets) */
+            /* When using a "real" qdisc, the qdisc determines the queue */
+            /* length. tx_queue_len is only used for the default case, */
+            /* without any more elaborate queuing. 100 is a reasonable */
+            /* compromise between decent burst-tolerance and protection */
+            /* against memory hogs. */
+}
+
+
+static int clip_create(int number)
+{
+        struct net_device *dev;
+        struct clip_priv *clip_priv;
+        int error;
+
+        if (number != -1) {
+                for (dev = clip_devs; dev; dev = PRIV(dev)->next)
+                        if (PRIV(dev)->number == number) return -EEXIST;
+        }
+        else {
+                number = 0;
+                for (dev = clip_devs; dev; dev = PRIV(dev)->next)
+                        if (PRIV(dev)->number >= number)
+                                number = PRIV(dev)->number+1;
+        }
+        dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup);
+        if (!dev)
+                return -ENOMEM;
+        clip_priv = PRIV(dev);
+        sprintf(dev->name,"atm%d",number);
+        spin_lock_init(&clip_priv->xoff_lock);
+        clip_priv->number = number;
+        error = register_netdev(dev);
+        if (error) {
+                free_netdev(dev);
+                return error;
+        }
+        clip_priv->next = clip_devs;
+        clip_devs = dev;
+        DPRINTK("registered (net:%s)\n",dev->name);
+        return number;
+}
+
+
+static int clip_device_event(struct notifier_block *this,unsigned long event,
+    void *dev)
+{
+        /* ignore non-CLIP devices */
+        if (((struct net_device *) dev)->type != ARPHRD_ATM ||
+            ((struct net_device *) dev)->hard_start_xmit != clip_start_xmit)
+                return NOTIFY_DONE;
+        switch (event) {
+                case NETDEV_UP:
+                        DPRINTK("clip_device_event NETDEV_UP\n");
+                        (void) to_atmarpd(act_up,PRIV(dev)->number,0);
+                        break;
+                case NETDEV_GOING_DOWN:
+                        DPRINTK("clip_device_event NETDEV_DOWN\n");
+                        (void) to_atmarpd(act_down,PRIV(dev)->number,0);
+                        break;
+                case NETDEV_CHANGE:
+                case NETDEV_CHANGEMTU:
+                        DPRINTK("clip_device_event NETDEV_CHANGE*\n");
+                        (void) to_atmarpd(act_change,PRIV(dev)->number,0);
+                        break;
+                case NETDEV_REBOOT:
+                case NETDEV_REGISTER:
+                case NETDEV_DOWN:
+                        DPRINTK("clip_device_event %ld\n",event);
+                        /* ignore */
+                        break;
+                default:
+                        printk(KERN_WARNING "clip_device_event: unknown event "
+                            "%ld\n",event);
+                        break;
+        }
+        return NOTIFY_DONE;
+}
+
+
+static int clip_inet_event(struct notifier_block *this,unsigned long event,
+    void *ifa)
+{
+        struct in_device *in_dev;
+
+        in_dev = ((struct in_ifaddr *) ifa)->ifa_dev;
+        if (!in_dev || !in_dev->dev) {
+                printk(KERN_WARNING "clip_inet_event: no device\n");
+                return NOTIFY_DONE;
+        }
+        /*
+         * Transitions are of the down-change-up type, so it's sufficient to
+         * handle the change on up.
+         */
+        if (event != NETDEV_UP) return NOTIFY_DONE;
+        return clip_device_event(this,NETDEV_CHANGE,in_dev->dev);
+}
+
+
+static struct notifier_block clip_dev_notifier = {
+        clip_device_event,
+        NULL,
+        0
+};
+
+
+
+static struct notifier_block clip_inet_notifier = {
+        clip_inet_event,
+        NULL,
+        0
+};
+
+
+
+static void atmarpd_close(struct atm_vcc *vcc)
+{
+        DPRINTK("atmarpd_close\n");
+        atmarpd = NULL; /* assumed to be atomic */
+        barrier();
+        unregister_inetaddr_notifier(&clip_inet_notifier);
+        unregister_netdevice_notifier(&clip_dev_notifier);
+        if (skb_peek(&sk_atm(vcc)->sk_receive_queue))
+                printk(KERN_ERR "atmarpd_close: closing with requests "
+                    "pending\n");
+        skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
+        DPRINTK("(done)\n");
+        module_put(THIS_MODULE);
+}
+
+
+static struct atmdev_ops atmarpd_dev_ops = {
+        .close = atmarpd_close
+};
+
+
+static struct atm_dev atmarpd_dev = {
+        .ops =                  &atmarpd_dev_ops,
+        .type =                 "arpd",
+        .number =               999,
+        .lock =                 SPIN_LOCK_UNLOCKED
+};
+
+
+static int atm_init_atmarp(struct atm_vcc *vcc)
+{
+        if (atmarpd) return -EADDRINUSE;
+        if (start_timer) {
+                start_timer = 0;
+                init_timer(&idle_timer);
+                idle_timer.expires = jiffies+CLIP_CHECK_INTERVAL*HZ;
+                idle_timer.function = idle_timer_check;
+                add_timer(&idle_timer);
+        }
+        atmarpd = vcc;
+        set_bit(ATM_VF_META,&vcc->flags);
+        set_bit(ATM_VF_READY,&vcc->flags);
+            /* allow replies and avoid getting closed if signaling dies */
+        vcc->dev = &atmarpd_dev;
+        vcc_insert_socket(sk_atm(vcc));
+        vcc->push = NULL;
+        vcc->pop = NULL; /* crash */
+        vcc->push_oam = NULL; /* crash */
+        if (register_netdevice_notifier(&clip_dev_notifier))
+                printk(KERN_ERR "register_netdevice_notifier failed\n");
+        if (register_inetaddr_notifier(&clip_inet_notifier))
+                printk(KERN_ERR "register_inetaddr_notifier failed\n");
+        return 0;
+}
+
+static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+        struct atm_vcc *vcc = ATM_SD(sock);
+        int err = 0;
+
+        switch (cmd) {
+                case SIOCMKCLIP:
+                case ATMARPD_CTRL:
+                case ATMARP_MKIP:
+                case ATMARP_SETENTRY:
+                case ATMARP_ENCAP:
+                        if (!capable(CAP_NET_ADMIN))
+                                return -EPERM;
+                        break;
+                default:
+                        return -ENOIOCTLCMD;
+        }
+
+        switch (cmd) {
+                case SIOCMKCLIP:
+                        err = clip_create(arg);
+                        break;
+                case ATMARPD_CTRL:
+                        err = atm_init_atmarp(vcc);
+                        if (!err) {
+                                sock->state = SS_CONNECTED;
+                                __module_get(THIS_MODULE);
+                        }
+                        break;
+                case ATMARP_MKIP:
+                        err = clip_mkip(vcc ,arg);
+                        break;
+                case ATMARP_SETENTRY:
+                        err = clip_setentry(vcc, arg);
+                        break;
+                case ATMARP_ENCAP:
+                        err = clip_encap(vcc, arg);
+                        break;
+        }
+        return err;
+}
+
+static struct atm_ioctl clip_ioctl_ops = {
+        .owner  = THIS_MODULE,
+        .ioctl  = clip_ioctl,
+};
+
+#ifdef CONFIG_PROC_FS
+
+static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
+{
+        static int code[] = { 1,2,10,6,1,0 };
+        static int e164[] = { 1,8,4,6,1,0 };
+
+        if (*addr->sas_addr.pub) {
+                seq_printf(seq, "%s", addr->sas_addr.pub);
+                if (*addr->sas_addr.prv)
+                        seq_putc(seq, '+');
+        } else if (!*addr->sas_addr.prv) {
+                seq_printf(seq, "%s", "(none)");
+                return;
+        }
+        if (*addr->sas_addr.prv) {
+                unsigned char *prv = addr->sas_addr.prv;
+                int *fields;
+                int i, j;
+
+                fields = *prv == ATM_AFI_E164 ? e164 : code;
+                for (i = 0; fields[i]; i++) {
+                        for (j = fields[i]; j; j--)
+                                seq_printf(seq, "%02X", *prv++);
+                        if (fields[i+1])
+                                seq_putc(seq, '.');
+                }
+        }
+}
+
+/* This means the neighbour entry has no attached VCC objects. */
+#define SEQ_NO_VCC_TOKEN        ((void *) 2)
+
+static void atmarp_info(struct seq_file *seq, struct net_device *dev,
+                        struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
+{
+        unsigned long exp;
+        char buf[17];
+        int svc, llc, off;
+
+        svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
+               (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC));
+
+        llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
+               clip_vcc->encap);
+
+        if (clip_vcc == SEQ_NO_VCC_TOKEN)
+                exp = entry->neigh->used;
+        else
+                exp = clip_vcc->last_use;
+
+        exp = (jiffies - exp) / HZ;
+
+        seq_printf(seq, "%-6s%-4s%-4s%5ld ",
+                   dev->name,
+                   svc ? "SVC" : "PVC",
+                   llc ? "LLC" : "NULL",
+                   exp);
+
+        off = scnprintf(buf, sizeof(buf) - 1, "%d.%d.%d.%d",
+                        NIPQUAD(entry->ip));
+        while (off < 16)
+                buf[off++] = ' ';
+        buf[off] = '\0';
+        seq_printf(seq, "%s", buf);
+
+        if (clip_vcc == SEQ_NO_VCC_TOKEN) {
+                if (time_before(jiffies, entry->expires))
+                        seq_printf(seq, "(resolving)\n");
+                else
+                        seq_printf(seq, "(expired, ref %d)\n",
+                                   atomic_read(&entry->neigh->refcnt));
+        } else if (!svc) {
+                seq_printf(seq, "%d.%d.%d\n",
+                           clip_vcc->vcc->dev->number,
+                           clip_vcc->vcc->vpi,
+                           clip_vcc->vcc->vci);
+        } else {
+                svc_addr(seq, &clip_vcc->vcc->remote);
+                seq_putc(seq, '\n');
+        }
+}
+
+struct clip_seq_state {
+        /* This member must be first. */
+        struct neigh_seq_state ns;
+
+        /* Local to clip specific iteration. */
+        struct clip_vcc *vcc;
+};
+
+static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
+                                          struct clip_vcc *curr)
+{
+        if (!curr) {
+                curr = e->vccs;
+                if (!curr)
+                        return SEQ_NO_VCC_TOKEN;
+                return curr;
+        }
+        if (curr == SEQ_NO_VCC_TOKEN)
+                return NULL;
+
+        curr = curr->next;
+
+        return curr;
+}
+
+static void *clip_seq_vcc_walk(struct clip_seq_state *state,
+                               struct atmarp_entry *e, loff_t *pos)
+{
+        struct clip_vcc *vcc = state->vcc;
+
+        vcc = clip_seq_next_vcc(e, vcc);
+        if (vcc && pos != NULL) {
+                while (*pos) {
+                        vcc = clip_seq_next_vcc(e, vcc);
+                        if (!vcc)
+                                break;
+                        --(*pos);
+                }
+        }
+        state->vcc = vcc;
+
+        return vcc;
+}
+  
+static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
+                               struct neighbour *n, loff_t *pos)
+{
+        struct clip_seq_state *state = (struct clip_seq_state *) _state;
+
+        return clip_seq_vcc_walk(state, NEIGH2ENTRY(n), pos);
+}
+
+static void *clip_seq_start(struct seq_file *seq, loff_t *pos)
+{
+        return neigh_seq_start(seq, pos, &clip_tbl, NEIGH_SEQ_NEIGH_ONLY);
+}
+
+static int clip_seq_show(struct seq_file *seq, void *v)
+{
+        static char atm_arp_banner[] = 
+                "IPitf TypeEncp Idle IP address      ATM address\n";
+
+        if (v == SEQ_START_TOKEN) {
+                seq_puts(seq, atm_arp_banner);
+        } else {
+                struct clip_seq_state *state = seq->private;
+                struct neighbour *n = v;
+                struct clip_vcc *vcc = state->vcc;
+
+                atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc);
+        }
+        return 0;
+}
+
+static struct seq_operations arp_seq_ops = {
+        .start  = clip_seq_start,
+        .next   = neigh_seq_next,
+        .stop   = neigh_seq_stop,
+        .show   = clip_seq_show,
+};
+
+static int arp_seq_open(struct inode *inode, struct file *file)
+{
+        struct clip_seq_state *state;
+        struct seq_file *seq;
+        int rc = -EAGAIN;
+
+        state = kmalloc(sizeof(*state), GFP_KERNEL);
+        if (!state) {
+                rc = -ENOMEM;
+                goto out_kfree;
+        }
+        memset(state, 0, sizeof(*state));
+        state->ns.neigh_sub_iter = clip_seq_sub_iter;
+
+        rc = seq_open(file, &arp_seq_ops);
+        if (rc)
+                goto out_kfree;
+
+        seq = file->private_data;
+        seq->private = state;
+out:
+        return rc;
+
+out_kfree:
+        kfree(state);
+        goto out;
+}
+
+static struct file_operations arp_seq_fops = {
+        .open           = arp_seq_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = seq_release_private,
+        .owner          = THIS_MODULE
+};
+#endif
+
+static int __init atm_clip_init(void)
+{
+        neigh_table_init(&clip_tbl);
+
+        clip_tbl_hook = &clip_tbl;
+        register_atm_ioctl(&clip_ioctl_ops);
+
+#ifdef CONFIG_PROC_FS
+{
+        struct proc_dir_entry *p;
+
+        p = create_proc_entry("arp", S_IRUGO, atm_proc_root);
+        if (p)
+                p->proc_fops = &arp_seq_fops;
+}
+#endif
+
+        return 0;
+}
+
+static void __exit atm_clip_exit(void)
+{
+        struct net_device *dev, *next;
+
+        remove_proc_entry("arp", atm_proc_root);
+
+        deregister_atm_ioctl(&clip_ioctl_ops);
+
+        /* First, stop the idle timer, so it stops banging
+         * on the table.
+         */
+        if (start_timer == 0)
+                del_timer(&idle_timer);
+
+        /* Next, purge the table, so that the device
+         * unregister loop below does not hang due to
+         * device references remaining in the table.
+         */
+        neigh_ifdown(&clip_tbl, NULL);
+
+        dev = clip_devs;
+        while (dev) {
+                next = PRIV(dev)->next;
+                unregister_netdev(dev);
+                free_netdev(dev);
+                dev = next;
+        }
+
+        /* Now it is safe to fully shutdown whole table. */
+        neigh_table_clear(&clip_tbl);
+
+        clip_tbl_hook = NULL;
+}
+
+module_init(atm_clip_init);
+module_exit(atm_clip_exit);
+
+MODULE_LICENSE("GPL");