Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / atm / br2684.c
diff --git a/kernel/net/atm/br2684.c b/kernel/net/atm/br2684.c
new file mode 100644 (file)
index 0000000..cc78538
--- /dev/null
@@ -0,0 +1,886 @@
+/*
+ * Ethernet netdevice using ATM AAL5 as underlying carrier
+ * (RFC1483 obsoleted by RFC2684) for Linux
+ *
+ * Authors: Marcell GAL, 2000, XDSL Ltd, Hungary
+ *          Eric Kinzie, 2006-2007, US Naval Research Laboratory
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/etherdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/ip.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <net/arp.h>
+#include <linux/atm.h>
+#include <linux/atmdev.h>
+#include <linux/capability.h>
+#include <linux/seq_file.h>
+
+#include <linux/atmbr2684.h>
+
+#include "common.h"
+
+static void skb_debug(const struct sk_buff *skb)
+{
+#ifdef SKB_DEBUG
+#define NUM2PRINT 50
+       print_hex_dump(KERN_DEBUG, "br2684: skb: ", DUMP_OFFSET,
+                      16, 1, skb->data, min(NUM2PRINT, skb->len), true);
+#endif
+}
+
+#define BR2684_ETHERTYPE_LEN   2
+#define BR2684_PAD_LEN         2
+
+#define LLC            0xaa, 0xaa, 0x03
+#define SNAP_BRIDGED   0x00, 0x80, 0xc2
+#define SNAP_ROUTED    0x00, 0x00, 0x00
+#define PID_ETHERNET   0x00, 0x07
+#define ETHERTYPE_IPV4 0x08, 0x00
+#define ETHERTYPE_IPV6 0x86, 0xdd
+#define PAD_BRIDGED    0x00, 0x00
+
+static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
+static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
+static const unsigned char llc_oui_pid_pad[] =
+                       { LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
+static const unsigned char pad[] = { PAD_BRIDGED };
+static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
+static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
+
+enum br2684_encaps {
+       e_vc = BR2684_ENCAPS_VC,
+       e_llc = BR2684_ENCAPS_LLC,
+};
+
+struct br2684_vcc {
+       struct atm_vcc *atmvcc;
+       struct net_device *device;
+       /* keep old push, pop functions for chaining */
+       void (*old_push)(struct atm_vcc *vcc, struct sk_buff *skb);
+       void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb);
+       void (*old_release_cb)(struct atm_vcc *vcc);
+       struct module *old_owner;
+       enum br2684_encaps encaps;
+       struct list_head brvccs;
+#ifdef CONFIG_ATM_BR2684_IPFILTER
+       struct br2684_filter filter;
+#endif /* CONFIG_ATM_BR2684_IPFILTER */
+       unsigned int copies_needed, copies_failed;
+       atomic_t qspace;
+};
+
+struct br2684_dev {
+       struct net_device *net_dev;
+       struct list_head br2684_devs;
+       int number;
+       struct list_head brvccs;        /* one device <=> one vcc (before xmas) */
+       int mac_was_set;
+       enum br2684_payload payload;
+};
+
+/*
+ * This lock should be held for writing any time the list of devices or
+ * their attached vcc's could be altered.  It should be held for reading
+ * any time these are being queried.  Note that we sometimes need to
+ * do read-locking under interrupt context, so write locking must block
+ * the current CPU's interrupts
+ */
+static DEFINE_RWLOCK(devs_lock);
+
+static LIST_HEAD(br2684_devs);
+
+static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
+{
+       return netdev_priv(net_dev);
+}
+
+static inline struct net_device *list_entry_brdev(const struct list_head *le)
+{
+       return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
+}
+
+static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
+{
+       return (struct br2684_vcc *)(atmvcc->user_back);
+}
+
+static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
+{
+       return list_entry(le, struct br2684_vcc, brvccs);
+}
+
+/* Caller should hold read_lock(&devs_lock) */
+static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
+{
+       struct list_head *lh;
+       struct net_device *net_dev;
+       switch (s->method) {
+       case BR2684_FIND_BYNUM:
+               list_for_each(lh, &br2684_devs) {
+                       net_dev = list_entry_brdev(lh);
+                       if (BRPRIV(net_dev)->number == s->spec.devnum)
+                               return net_dev;
+               }
+               break;
+       case BR2684_FIND_BYIFNAME:
+               list_for_each(lh, &br2684_devs) {
+                       net_dev = list_entry_brdev(lh);
+                       if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
+                               return net_dev;
+               }
+               break;
+       }
+       return NULL;
+}
+
+static int atm_dev_event(struct notifier_block *this, unsigned long event,
+                void *arg)
+{
+       struct atm_dev *atm_dev = arg;
+       struct list_head *lh;
+       struct net_device *net_dev;
+       struct br2684_vcc *brvcc;
+       struct atm_vcc *atm_vcc;
+       unsigned long flags;
+
+       pr_debug("event=%ld dev=%p\n", event, atm_dev);
+
+       read_lock_irqsave(&devs_lock, flags);
+       list_for_each(lh, &br2684_devs) {
+               net_dev = list_entry_brdev(lh);
+
+               list_for_each_entry(brvcc, &BRPRIV(net_dev)->brvccs, brvccs) {
+                       atm_vcc = brvcc->atmvcc;
+                       if (atm_vcc && brvcc->atmvcc->dev == atm_dev) {
+
+                               if (atm_vcc->dev->signal == ATM_PHY_SIG_LOST)
+                                       netif_carrier_off(net_dev);
+                               else
+                                       netif_carrier_on(net_dev);
+
+                       }
+               }
+       }
+       read_unlock_irqrestore(&devs_lock, flags);
+
+       return NOTIFY_DONE;
+}
+
+static struct notifier_block atm_dev_notifier = {
+       .notifier_call = atm_dev_event,
+};
+
+/* chained vcc->pop function.  Check if we should wake the netif_queue */
+static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
+{
+       struct br2684_vcc *brvcc = BR2684_VCC(vcc);
+
+       pr_debug("(vcc %p ; net_dev %p )\n", vcc, brvcc->device);
+       brvcc->old_pop(vcc, skb);
+
+       /* If the queue space just went up from zero, wake */
+       if (atomic_inc_return(&brvcc->qspace) == 1)
+               netif_wake_queue(brvcc->device);
+}
+
+/*
+ * Send a packet out a particular vcc.  Not to useful right now, but paves
+ * the way for multiple vcc's per itf.  Returns true if we can send,
+ * otherwise false
+ */
+static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
+                          struct br2684_vcc *brvcc)
+{
+       struct br2684_dev *brdev = BRPRIV(dev);
+       struct atm_vcc *atmvcc;
+       int minheadroom = (brvcc->encaps == e_llc) ?
+               ((brdev->payload == p_bridged) ?
+                       sizeof(llc_oui_pid_pad) : sizeof(llc_oui_ipv4)) :
+               ((brdev->payload == p_bridged) ? BR2684_PAD_LEN : 0);
+
+       if (skb_headroom(skb) < minheadroom) {
+               struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
+               brvcc->copies_needed++;
+               dev_kfree_skb(skb);
+               if (skb2 == NULL) {
+                       brvcc->copies_failed++;
+                       return 0;
+               }
+               skb = skb2;
+       }
+
+       if (brvcc->encaps == e_llc) {
+               if (brdev->payload == p_bridged) {
+                       skb_push(skb, sizeof(llc_oui_pid_pad));
+                       skb_copy_to_linear_data(skb, llc_oui_pid_pad,
+                                               sizeof(llc_oui_pid_pad));
+               } else if (brdev->payload == p_routed) {
+                       unsigned short prot = ntohs(skb->protocol);
+
+                       skb_push(skb, sizeof(llc_oui_ipv4));
+                       switch (prot) {
+                       case ETH_P_IP:
+                               skb_copy_to_linear_data(skb, llc_oui_ipv4,
+                                                       sizeof(llc_oui_ipv4));
+                               break;
+                       case ETH_P_IPV6:
+                               skb_copy_to_linear_data(skb, llc_oui_ipv6,
+                                                       sizeof(llc_oui_ipv6));
+                               break;
+                       default:
+                               dev_kfree_skb(skb);
+                               return 0;
+                       }
+               }
+       } else { /* e_vc */
+               if (brdev->payload == p_bridged) {
+                       skb_push(skb, 2);
+                       memset(skb->data, 0, 2);
+               }
+       }
+       skb_debug(skb);
+
+       ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
+       pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
+       atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
+       ATM_SKB(skb)->atm_options = atmvcc->atm_options;
+       dev->stats.tx_packets++;
+       dev->stats.tx_bytes += skb->len;
+
+       if (atomic_dec_return(&brvcc->qspace) < 1) {
+               /* No more please! */
+               netif_stop_queue(brvcc->device);
+               /* We might have raced with br2684_pop() */
+               if (unlikely(atomic_read(&brvcc->qspace) > 0))
+                       netif_wake_queue(brvcc->device);
+       }
+
+       /* If this fails immediately, the skb will be freed and br2684_pop()
+          will wake the queue if appropriate. Just return an error so that
+          the stats are updated correctly */
+       return !atmvcc->send(atmvcc, skb);
+}
+
+static void br2684_release_cb(struct atm_vcc *atmvcc)
+{
+       struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
+
+       if (atomic_read(&brvcc->qspace) > 0)
+               netif_wake_queue(brvcc->device);
+
+       if (brvcc->old_release_cb)
+               brvcc->old_release_cb(atmvcc);
+}
+
+static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
+                                                  const struct br2684_dev *brdev)
+{
+       return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
+}
+
+static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
+                                    struct net_device *dev)
+{
+       struct br2684_dev *brdev = BRPRIV(dev);
+       struct br2684_vcc *brvcc;
+       struct atm_vcc *atmvcc;
+       netdev_tx_t ret = NETDEV_TX_OK;
+
+       pr_debug("skb_dst(skb)=%p\n", skb_dst(skb));
+       read_lock(&devs_lock);
+       brvcc = pick_outgoing_vcc(skb, brdev);
+       if (brvcc == NULL) {
+               pr_debug("no vcc attached to dev %s\n", dev->name);
+               dev->stats.tx_errors++;
+               dev->stats.tx_carrier_errors++;
+               /* netif_stop_queue(dev); */
+               dev_kfree_skb(skb);
+               goto out_devs;
+       }
+       atmvcc = brvcc->atmvcc;
+
+       bh_lock_sock(sk_atm(atmvcc));
+
+       if (test_bit(ATM_VF_RELEASED, &atmvcc->flags) ||
+           test_bit(ATM_VF_CLOSE, &atmvcc->flags) ||
+           !test_bit(ATM_VF_READY, &atmvcc->flags)) {
+               dev->stats.tx_dropped++;
+               dev_kfree_skb(skb);
+               goto out;
+       }
+
+       if (sock_owned_by_user(sk_atm(atmvcc))) {
+               netif_stop_queue(brvcc->device);
+               ret = NETDEV_TX_BUSY;
+               goto out;
+       }
+
+       if (!br2684_xmit_vcc(skb, dev, brvcc)) {
+               /*
+                * We should probably use netif_*_queue() here, but that
+                * involves added complication.  We need to walk before
+                * we can run.
+                *
+                * Don't free here! this pointer might be no longer valid!
+                */
+               dev->stats.tx_errors++;
+               dev->stats.tx_fifo_errors++;
+       }
+ out:
+       bh_unlock_sock(sk_atm(atmvcc));
+ out_devs:
+       read_unlock(&devs_lock);
+       return ret;
+}
+
+/*
+ * We remember when the MAC gets set, so we don't override it later with
+ * the ESI of the ATM card of the first VC
+ */
+static int br2684_mac_addr(struct net_device *dev, void *p)
+{
+       int err = eth_mac_addr(dev, p);
+       if (!err)
+               BRPRIV(dev)->mac_was_set = 1;
+       return err;
+}
+
+#ifdef CONFIG_ATM_BR2684_IPFILTER
+/* this IOCTL is experimental. */
+static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
+{
+       struct br2684_vcc *brvcc;
+       struct br2684_filter_set fs;
+
+       if (copy_from_user(&fs, arg, sizeof fs))
+               return -EFAULT;
+       if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
+               /*
+                * This is really a per-vcc thing, but we can also search
+                * by device.
+                */
+               struct br2684_dev *brdev;
+               read_lock(&devs_lock);
+               brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
+               if (brdev == NULL || list_empty(&brdev->brvccs) ||
+                   brdev->brvccs.next != brdev->brvccs.prev)   /* >1 VCC */
+                       brvcc = NULL;
+               else
+                       brvcc = list_entry_brvcc(brdev->brvccs.next);
+               read_unlock(&devs_lock);
+               if (brvcc == NULL)
+                       return -ESRCH;
+       } else
+               brvcc = BR2684_VCC(atmvcc);
+       memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
+       return 0;
+}
+
+/* Returns 1 if packet should be dropped */
+static inline int
+packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
+{
+       if (brvcc->filter.netmask == 0)
+               return 0;       /* no filter in place */
+       if (type == htons(ETH_P_IP) &&
+           (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
+            netmask) == brvcc->filter.prefix)
+               return 0;
+       if (type == htons(ETH_P_ARP))
+               return 0;
+       /*
+        * TODO: we should probably filter ARPs too.. don't want to have
+        * them returning values that don't make sense, or is that ok?
+        */
+       return 1;               /* drop */
+}
+#endif /* CONFIG_ATM_BR2684_IPFILTER */
+
+static void br2684_close_vcc(struct br2684_vcc *brvcc)
+{
+       pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
+       write_lock_irq(&devs_lock);
+       list_del(&brvcc->brvccs);
+       write_unlock_irq(&devs_lock);
+       brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
+       brvcc->atmvcc->release_cb = brvcc->old_release_cb;
+       brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
+       module_put(brvcc->old_owner);
+       kfree(brvcc);
+}
+
+/* when AAL5 PDU comes in: */
+static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
+{
+       struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
+       struct net_device *net_dev = brvcc->device;
+       struct br2684_dev *brdev = BRPRIV(net_dev);
+
+       pr_debug("\n");
+
+       if (unlikely(skb == NULL)) {
+               /* skb==NULL means VCC is being destroyed */
+               br2684_close_vcc(brvcc);
+               if (list_empty(&brdev->brvccs)) {
+                       write_lock_irq(&devs_lock);
+                       list_del(&brdev->br2684_devs);
+                       write_unlock_irq(&devs_lock);
+                       unregister_netdev(net_dev);
+                       free_netdev(net_dev);
+               }
+               return;
+       }
+
+       skb_debug(skb);
+       atm_return(atmvcc, skb->truesize);
+       pr_debug("skb from brdev %p\n", brdev);
+       if (brvcc->encaps == e_llc) {
+
+               if (skb->len > 7 && skb->data[7] == 0x01)
+                       __skb_trim(skb, skb->len - 4);
+
+               /* accept packets that have "ipv[46]" in the snap header */
+               if ((skb->len >= (sizeof(llc_oui_ipv4))) &&
+                   (memcmp(skb->data, llc_oui_ipv4,
+                           sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
+                       if (memcmp(skb->data + 6, ethertype_ipv6,
+                                  sizeof(ethertype_ipv6)) == 0)
+                               skb->protocol = htons(ETH_P_IPV6);
+                       else if (memcmp(skb->data + 6, ethertype_ipv4,
+                                       sizeof(ethertype_ipv4)) == 0)
+                               skb->protocol = htons(ETH_P_IP);
+                       else
+                               goto error;
+                       skb_pull(skb, sizeof(llc_oui_ipv4));
+                       skb_reset_network_header(skb);
+                       skb->pkt_type = PACKET_HOST;
+               /*
+                * Let us waste some time for checking the encapsulation.
+                * Note, that only 7 char is checked so frames with a valid FCS
+                * are also accepted (but FCS is not checked of course).
+                */
+               } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
+                          (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
+                       skb_pull(skb, sizeof(llc_oui_pid_pad));
+                       skb->protocol = eth_type_trans(skb, net_dev);
+               } else
+                       goto error;
+
+       } else { /* e_vc */
+               if (brdev->payload == p_routed) {
+                       struct iphdr *iph;
+
+                       skb_reset_network_header(skb);
+                       iph = ip_hdr(skb);
+                       if (iph->version == 4)
+                               skb->protocol = htons(ETH_P_IP);
+                       else if (iph->version == 6)
+                               skb->protocol = htons(ETH_P_IPV6);
+                       else
+                               goto error;
+                       skb->pkt_type = PACKET_HOST;
+               } else { /* p_bridged */
+                       /* first 2 chars should be 0 */
+                       if (memcmp(skb->data, pad, BR2684_PAD_LEN) != 0)
+                               goto error;
+                       skb_pull(skb, BR2684_PAD_LEN);
+                       skb->protocol = eth_type_trans(skb, net_dev);
+               }
+       }
+
+#ifdef CONFIG_ATM_BR2684_IPFILTER
+       if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
+               goto dropped;
+#endif /* CONFIG_ATM_BR2684_IPFILTER */
+       skb->dev = net_dev;
+       ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
+       pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
+       skb_debug(skb);
+       /* sigh, interface is down? */
+       if (unlikely(!(net_dev->flags & IFF_UP)))
+               goto dropped;
+       net_dev->stats.rx_packets++;
+       net_dev->stats.rx_bytes += skb->len;
+       memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
+       netif_rx(skb);
+       return;
+
+dropped:
+       net_dev->stats.rx_dropped++;
+       goto free_skb;
+error:
+       net_dev->stats.rx_errors++;
+free_skb:
+       dev_kfree_skb(skb);
+}
+
+/*
+ * Assign a vcc to a dev
+ * Note: we do not have explicit unassign, but look at _push()
+ */
+static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
+{
+       struct br2684_vcc *brvcc;
+       struct br2684_dev *brdev;
+       struct net_device *net_dev;
+       struct atm_backend_br2684 be;
+       int err;
+
+       if (copy_from_user(&be, arg, sizeof be))
+               return -EFAULT;
+       brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
+       if (!brvcc)
+               return -ENOMEM;
+       /*
+        * Allow two packets in the ATM queue. One actually being sent, and one
+        * for the ATM 'TX done' handler to send. It shouldn't take long to get
+        * the next one from the netdev queue, when we need it. More than that
+        * would be bufferbloat.
+        */
+       atomic_set(&brvcc->qspace, 2);
+       write_lock_irq(&devs_lock);
+       net_dev = br2684_find_dev(&be.ifspec);
+       if (net_dev == NULL) {
+               pr_err("tried to attach to non-existent device\n");
+               err = -ENXIO;
+               goto error;
+       }
+       brdev = BRPRIV(net_dev);
+       if (atmvcc->push == NULL) {
+               err = -EBADFD;
+               goto error;
+       }
+       if (!list_empty(&brdev->brvccs)) {
+               /* Only 1 VCC/dev right now */
+               err = -EEXIST;
+               goto error;
+       }
+       if (be.fcs_in != BR2684_FCSIN_NO ||
+           be.fcs_out != BR2684_FCSOUT_NO ||
+           be.fcs_auto || be.has_vpiid || be.send_padding ||
+           (be.encaps != BR2684_ENCAPS_VC &&
+            be.encaps != BR2684_ENCAPS_LLC) ||
+           be.min_size != 0) {
+               err = -EINVAL;
+               goto error;
+       }
+       pr_debug("vcc=%p, encaps=%d, brvcc=%p\n", atmvcc, be.encaps, brvcc);
+       if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
+               unsigned char *esi = atmvcc->dev->esi;
+               if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
+                       memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
+               else
+                       net_dev->dev_addr[2] = 1;
+       }
+       list_add(&brvcc->brvccs, &brdev->brvccs);
+       write_unlock_irq(&devs_lock);
+       brvcc->device = net_dev;
+       brvcc->atmvcc = atmvcc;
+       atmvcc->user_back = brvcc;
+       brvcc->encaps = (enum br2684_encaps)be.encaps;
+       brvcc->old_push = atmvcc->push;
+       brvcc->old_pop = atmvcc->pop;
+       brvcc->old_release_cb = atmvcc->release_cb;
+       brvcc->old_owner = atmvcc->owner;
+       barrier();
+       atmvcc->push = br2684_push;
+       atmvcc->pop = br2684_pop;
+       atmvcc->release_cb = br2684_release_cb;
+       atmvcc->owner = THIS_MODULE;
+
+       /* initialize netdev carrier state */
+       if (atmvcc->dev->signal == ATM_PHY_SIG_LOST)
+               netif_carrier_off(net_dev);
+       else
+               netif_carrier_on(net_dev);
+
+       __module_get(THIS_MODULE);
+
+       /* re-process everything received between connection setup and
+          backend setup */
+       vcc_process_recv_queue(atmvcc);
+       return 0;
+
+error:
+       write_unlock_irq(&devs_lock);
+       kfree(brvcc);
+       return err;
+}
+
+static const struct net_device_ops br2684_netdev_ops = {
+       .ndo_start_xmit         = br2684_start_xmit,
+       .ndo_set_mac_address    = br2684_mac_addr,
+       .ndo_change_mtu         = eth_change_mtu,
+       .ndo_validate_addr      = eth_validate_addr,
+};
+
+static const struct net_device_ops br2684_netdev_ops_routed = {
+       .ndo_start_xmit         = br2684_start_xmit,
+       .ndo_set_mac_address    = br2684_mac_addr,
+       .ndo_change_mtu         = eth_change_mtu
+};
+
+static void br2684_setup(struct net_device *netdev)
+{
+       struct br2684_dev *brdev = BRPRIV(netdev);
+
+       ether_setup(netdev);
+       netdev->hard_header_len += sizeof(llc_oui_pid_pad); /* worst case */
+       brdev->net_dev = netdev;
+
+       netdev->netdev_ops = &br2684_netdev_ops;
+
+       INIT_LIST_HEAD(&brdev->brvccs);
+}
+
+static void br2684_setup_routed(struct net_device *netdev)
+{
+       struct br2684_dev *brdev = BRPRIV(netdev);
+
+       brdev->net_dev = netdev;
+       netdev->hard_header_len = sizeof(llc_oui_ipv4); /* worst case */
+       netdev->netdev_ops = &br2684_netdev_ops_routed;
+       netdev->addr_len = 0;
+       netdev->mtu = 1500;
+       netdev->type = ARPHRD_PPP;
+       netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
+       netdev->tx_queue_len = 100;
+       INIT_LIST_HEAD(&brdev->brvccs);
+}
+
+static int br2684_create(void __user *arg)
+{
+       int err;
+       struct net_device *netdev;
+       struct br2684_dev *brdev;
+       struct atm_newif_br2684 ni;
+       enum br2684_payload payload;
+
+       pr_debug("\n");
+
+       if (copy_from_user(&ni, arg, sizeof ni))
+               return -EFAULT;
+
+       if (ni.media & BR2684_FLAG_ROUTED)
+               payload = p_routed;
+       else
+               payload = p_bridged;
+       ni.media &= 0xffff;     /* strip flags */
+
+       if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
+               return -EINVAL;
+
+       netdev = alloc_netdev(sizeof(struct br2684_dev),
+                             ni.ifname[0] ? ni.ifname : "nas%d",
+                             NET_NAME_UNKNOWN,
+                             (payload == p_routed) ? br2684_setup_routed : br2684_setup);
+       if (!netdev)
+               return -ENOMEM;
+
+       brdev = BRPRIV(netdev);
+
+       pr_debug("registered netdev %s\n", netdev->name);
+       /* open, stop, do_ioctl ? */
+       err = register_netdev(netdev);
+       if (err < 0) {
+               pr_err("register_netdev failed\n");
+               free_netdev(netdev);
+               return err;
+       }
+
+       write_lock_irq(&devs_lock);
+
+       brdev->payload = payload;
+
+       if (list_empty(&br2684_devs)) {
+               /* 1st br2684 device */
+               brdev->number = 1;
+       } else
+               brdev->number = BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
+
+       list_add_tail(&brdev->br2684_devs, &br2684_devs);
+       write_unlock_irq(&devs_lock);
+       return 0;
+}
+
+/*
+ * This handles ioctls actually performed on our vcc - we must return
+ * -ENOIOCTLCMD for any unrecognized ioctl
+ */
+static int br2684_ioctl(struct socket *sock, unsigned int cmd,
+                       unsigned long arg)
+{
+       struct atm_vcc *atmvcc = ATM_SD(sock);
+       void __user *argp = (void __user *)arg;
+       atm_backend_t b;
+
+       int err;
+       switch (cmd) {
+       case ATM_SETBACKEND:
+       case ATM_NEWBACKENDIF:
+               err = get_user(b, (atm_backend_t __user *) argp);
+               if (err)
+                       return -EFAULT;
+               if (b != ATM_BACKEND_BR2684)
+                       return -ENOIOCTLCMD;
+               if (!capable(CAP_NET_ADMIN))
+                       return -EPERM;
+               if (cmd == ATM_SETBACKEND) {
+                       if (sock->state != SS_CONNECTED)
+                               return -EINVAL;
+                       return br2684_regvcc(atmvcc, argp);
+               } else {
+                       return br2684_create(argp);
+               }
+#ifdef CONFIG_ATM_BR2684_IPFILTER
+       case BR2684_SETFILT:
+               if (atmvcc->push != br2684_push)
+                       return -ENOIOCTLCMD;
+               if (!capable(CAP_NET_ADMIN))
+                       return -EPERM;
+               err = br2684_setfilt(atmvcc, argp);
+
+               return err;
+#endif /* CONFIG_ATM_BR2684_IPFILTER */
+       }
+       return -ENOIOCTLCMD;
+}
+
+static struct atm_ioctl br2684_ioctl_ops = {
+       .owner = THIS_MODULE,
+       .ioctl = br2684_ioctl,
+};
+
+#ifdef CONFIG_PROC_FS
+static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
+       __acquires(devs_lock)
+{
+       read_lock(&devs_lock);
+       return seq_list_start(&br2684_devs, *pos);
+}
+
+static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
+{
+       return seq_list_next(v, &br2684_devs, pos);
+}
+
+static void br2684_seq_stop(struct seq_file *seq, void *v)
+       __releases(devs_lock)
+{
+       read_unlock(&devs_lock);
+}
+
+static int br2684_seq_show(struct seq_file *seq, void *v)
+{
+       const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
+                                                   br2684_devs);
+       const struct net_device *net_dev = brdev->net_dev;
+       const struct br2684_vcc *brvcc;
+
+       seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
+                  net_dev->name,
+                  brdev->number,
+                  net_dev->dev_addr,
+                  brdev->mac_was_set ? "set" : "auto");
+
+       list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
+               seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
+                          ", failed copies %u/%u"
+                          "\n", brvcc->atmvcc->dev->number,
+                          brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
+                          (brvcc->encaps == e_llc) ? "LLC" : "VC",
+                          (brdev->payload == p_bridged) ? "bridged" : "routed",
+                          brvcc->copies_failed, brvcc->copies_needed);
+#ifdef CONFIG_ATM_BR2684_IPFILTER
+#define b1(var, byte)  ((u8 *) &brvcc->filter.var)[byte]
+#define bs(var)                b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
+               if (brvcc->filter.netmask != 0)
+                       seq_printf(seq, "    filter=%d.%d.%d.%d/"
+                                  "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
+#undef bs
+#undef b1
+#endif /* CONFIG_ATM_BR2684_IPFILTER */
+       }
+       return 0;
+}
+
+static const struct seq_operations br2684_seq_ops = {
+       .start = br2684_seq_start,
+       .next = br2684_seq_next,
+       .stop = br2684_seq_stop,
+       .show = br2684_seq_show,
+};
+
+static int br2684_proc_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &br2684_seq_ops);
+}
+
+static const struct file_operations br2684_proc_ops = {
+       .owner = THIS_MODULE,
+       .open = br2684_proc_open,
+       .read = seq_read,
+       .llseek = seq_lseek,
+       .release = seq_release,
+};
+
+extern struct proc_dir_entry *atm_proc_root;   /* from proc.c */
+#endif /* CONFIG_PROC_FS */
+
+static int __init br2684_init(void)
+{
+#ifdef CONFIG_PROC_FS
+       struct proc_dir_entry *p;
+       p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
+       if (p == NULL)
+               return -ENOMEM;
+#endif
+       register_atm_ioctl(&br2684_ioctl_ops);
+       register_atmdevice_notifier(&atm_dev_notifier);
+       return 0;
+}
+
+static void __exit br2684_exit(void)
+{
+       struct net_device *net_dev;
+       struct br2684_dev *brdev;
+       struct br2684_vcc *brvcc;
+       deregister_atm_ioctl(&br2684_ioctl_ops);
+
+#ifdef CONFIG_PROC_FS
+       remove_proc_entry("br2684", atm_proc_root);
+#endif
+
+
+       unregister_atmdevice_notifier(&atm_dev_notifier);
+
+       while (!list_empty(&br2684_devs)) {
+               net_dev = list_entry_brdev(br2684_devs.next);
+               brdev = BRPRIV(net_dev);
+               while (!list_empty(&brdev->brvccs)) {
+                       brvcc = list_entry_brvcc(brdev->brvccs.next);
+                       br2684_close_vcc(brvcc);
+               }
+
+               list_del(&brdev->br2684_devs);
+               unregister_netdev(net_dev);
+               free_netdev(net_dev);
+       }
+}
+
+module_init(br2684_init);
+module_exit(br2684_exit);
+
+MODULE_AUTHOR("Marcell GAL");
+MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
+MODULE_LICENSE("GPL");