Linux-2.6.12-rc2

[mirror_ubuntu-artful-kernel.git] / net / 8021q / vlan.c

/*
 * INET         802.1Q VLAN
 *              Ethernet-type device handling.
 *
 * Authors:     Ben Greear <greearb@candelatech.com>
 *              Please send support related email to: vlan@scry.wanfear.com
 *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
 * 
 * Fixes:
 *              Fix for packet capture - Nick Eggleston <nick@dccinc.com>;
 *              Add HW acceleration hooks - David S. Miller <davem@redhat.com>;
 *              Correct all the locking - David S. Miller <davem@redhat.com>;
 *              Use hash table for VLAN groups - David S. Miller <davem@redhat.com>
 *
 *              This program is free software; you can redistribute it and/or
 *              modify it under the terms of the GNU General Public License
 *              as published by the Free Software Foundation; either version
 *              2 of the License, or (at your option) any later version.
 */

#include <asm/uaccess.h> /* for copy_from_user */
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/datalink.h>
#include <linux/mm.h>
#include <linux/in.h>
#include <linux/init.h>
#include <net/p8022.h>
#include <net/arp.h>
#include <linux/rtnetlink.h>
#include <linux/notifier.h>

#include <linux/if_vlan.h>
#include "vlan.h"
#include "vlanproc.h"

#define DRV_VERSION "1.8"

/* Global VLAN variables */

/* Our listing of VLAN group(s) */
static struct hlist_head vlan_group_hash[VLAN_GRP_HASH_SIZE];
#define vlan_grp_hashfn(IDX)    ((((IDX) >> VLAN_GRP_HASH_SHIFT) ^ (IDX)) & VLAN_GRP_HASH_MASK)

static char vlan_fullname[] = "802.1Q VLAN Support";
static char vlan_version[] = DRV_VERSION;
static char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>";
static char vlan_buggyright[] = "David S. Miller <davem@redhat.com>";

static int vlan_device_event(struct notifier_block *, unsigned long, void *);
static int vlan_ioctl_handler(void __user *);
static int unregister_vlan_dev(struct net_device *, unsigned short );

static struct notifier_block vlan_notifier_block = {
        .notifier_call = vlan_device_event,
};

/* These may be changed at run-time through IOCTLs */

/* Determines interface naming scheme. */
unsigned short vlan_name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;

static struct packet_type vlan_packet_type = {
        .type = __constant_htons(ETH_P_8021Q),
        .func = vlan_skb_recv, /* VLAN receive method */
};

/* Bits of netdev state that are propagated from real device to virtual */
#define VLAN_LINK_STATE_MASK \
        ((1<<__LINK_STATE_PRESENT)|(1<<__LINK_STATE_NOCARRIER))

/* End of global variables definitions. */

/*
 * Function vlan_proto_init (pro)
 *
 *    Initialize VLAN protocol layer, 
 *
 */
static int __init vlan_proto_init(void)
{
        int err;

        printk(VLAN_INF "%s v%s %s\n",
               vlan_fullname, vlan_version, vlan_copyright);
        printk(VLAN_INF "All bugs added by %s\n",
               vlan_buggyright);

        /* proc file system initialization */
        err = vlan_proc_init();
        if (err < 0) {
                printk(KERN_ERR 
                       "%s %s: can't create entry in proc filesystem!\n",
                       __FUNCTION__, VLAN_NAME);
                return err;
        }

        dev_add_pack(&vlan_packet_type);

        /* Register us to receive netdevice events */
        err = register_netdevice_notifier(&vlan_notifier_block);
        if (err < 0) {
                dev_remove_pack(&vlan_packet_type);
                vlan_proc_cleanup();
                return err;
        }

        vlan_ioctl_set(vlan_ioctl_handler);

        return 0;
}

/* Cleanup all vlan devices 
 * Note: devices that have been registered that but not
 * brought up will exist but have no module ref count.
 */
static void __exit vlan_cleanup_devices(void)
{
        struct net_device *dev, *nxt;

        rtnl_lock();
        for (dev = dev_base; dev; dev = nxt) {
                nxt = dev->next;
                if (dev->priv_flags & IFF_802_1Q_VLAN) {
                        unregister_vlan_dev(VLAN_DEV_INFO(dev)->real_dev,
                                            VLAN_DEV_INFO(dev)->vlan_id);

                        unregister_netdevice(dev);
                }
        }
        rtnl_unlock();
}

/*
 *     Module 'remove' entry point.
 *     o delete /proc/net/router directory and static entries.
 */ 
static void __exit vlan_cleanup_module(void)
{
        int i;

        vlan_ioctl_set(NULL);

        /* Un-register us from receiving netdevice events */
        unregister_netdevice_notifier(&vlan_notifier_block);

        dev_remove_pack(&vlan_packet_type);
        vlan_cleanup_devices();

        /* This table must be empty if there are no module
         * references left.
         */
        for (i = 0; i < VLAN_GRP_HASH_SIZE; i++) {
                BUG_ON(!hlist_empty(&vlan_group_hash[i]));
        }
        vlan_proc_cleanup();

        synchronize_net();
}

module_init(vlan_proto_init);
module_exit(vlan_cleanup_module);

/* Must be invoked with RCU read lock (no preempt) */
static struct vlan_group *__vlan_find_group(int real_dev_ifindex)
{
        struct vlan_group *grp;
        struct hlist_node *n;
        int hash = vlan_grp_hashfn(real_dev_ifindex);

        hlist_for_each_entry_rcu(grp, n, &vlan_group_hash[hash], hlist) {
                if (grp->real_dev_ifindex == real_dev_ifindex)
                        return grp;
        }

        return NULL;
}

/*  Find the protocol handler.  Assumes VID < VLAN_VID_MASK.
 *
 * Must be invoked with RCU read lock (no preempt)
 */
struct net_device *__find_vlan_dev(struct net_device *real_dev,
                                   unsigned short VID)
{
        struct vlan_group *grp = __vlan_find_group(real_dev->ifindex);

        if (grp)
                return grp->vlan_devices[VID];

        return NULL;
}

static void vlan_rcu_free(struct rcu_head *rcu)
{
        kfree(container_of(rcu, struct vlan_group, rcu));
}


/* This returns 0 if everything went fine.
 * It will return 1 if the group was killed as a result.
 * A negative return indicates failure.
 *
 * The RTNL lock must be held.
 */
static int unregister_vlan_dev(struct net_device *real_dev,
                               unsigned short vlan_id)
{
        struct net_device *dev = NULL;
        int real_dev_ifindex = real_dev->ifindex;
        struct vlan_group *grp;
        int i, ret;

#ifdef VLAN_DEBUG
        printk(VLAN_DBG "%s: VID: %i\n", __FUNCTION__, vlan_id);
#endif

        /* sanity check */
        if (vlan_id >= VLAN_VID_MASK)
                return -EINVAL;

        ASSERT_RTNL();
        grp = __vlan_find_group(real_dev_ifindex);

        ret = 0;

        if (grp) {
                dev = grp->vlan_devices[vlan_id];
                if (dev) {
                        /* Remove proc entry */
                        vlan_proc_rem_dev(dev);

                        /* Take it out of our own structures, but be sure to
                         * interlock with HW accelerating devices or SW vlan
                         * input packet processing.
                         */
                        if (real_dev->features &
                            (NETIF_F_HW_VLAN_RX | NETIF_F_HW_VLAN_FILTER)) {
                                real_dev->vlan_rx_kill_vid(real_dev, vlan_id);
                        }

                        grp->vlan_devices[vlan_id] = NULL;
                        synchronize_net();


                        /* Caller unregisters (and if necessary, puts)
                         * VLAN device, but we get rid of the reference to
                         * real_dev here.
                         */
                        dev_put(real_dev);

                        /* If the group is now empty, kill off the
                         * group.
                         */
                        for (i = 0; i < VLAN_VID_MASK; i++)
                                if (grp->vlan_devices[i])
                                        break;

                        if (i == VLAN_VID_MASK) {
                                if (real_dev->features & NETIF_F_HW_VLAN_RX)
                                        real_dev->vlan_rx_register(real_dev, NULL);

                                hlist_del_rcu(&grp->hlist);

                                /* Free the group, after all cpu's are done. */
                                call_rcu(&grp->rcu, vlan_rcu_free);

                                grp = NULL;
                                ret = 1;
                        }
                }
        }

        return ret;
}

static int unregister_vlan_device(const char *vlan_IF_name)
{
        struct net_device *dev = NULL;
        int ret;


        dev = dev_get_by_name(vlan_IF_name);
        ret = -EINVAL;
        if (dev) {
                if (dev->priv_flags & IFF_802_1Q_VLAN) {
                        rtnl_lock();

                        ret = unregister_vlan_dev(VLAN_DEV_INFO(dev)->real_dev,
                                                  VLAN_DEV_INFO(dev)->vlan_id);

                        dev_put(dev);
                        unregister_netdevice(dev);

                        rtnl_unlock();

                        if (ret == 1)
                                ret = 0;
                } else {
                        printk(VLAN_ERR 
                               "%s: ERROR:      Tried to remove a non-vlan device "
                               "with VLAN code, name: %s  priv_flags: %hX\n",
                               __FUNCTION__, dev->name, dev->priv_flags);
                        dev_put(dev);
                        ret = -EPERM;
                }
        } else {
#ifdef VLAN_DEBUG
                printk(VLAN_DBG "%s: WARNING: Could not find dev.\n", __FUNCTION__);
#endif
                ret = -EINVAL;
        }

        return ret;
}

static void vlan_setup(struct net_device *new_dev)
{
        SET_MODULE_OWNER(new_dev);
            
        /* new_dev->ifindex = 0;  it will be set when added to
         * the global list.
         * iflink is set as well.
         */
        new_dev->get_stats = vlan_dev_get_stats;

        /* Make this thing known as a VLAN device */
        new_dev->priv_flags |= IFF_802_1Q_VLAN;
                                
        /* Set us up to have no queue, as the underlying Hardware device
         * can do all the queueing we could want.
         */
        new_dev->tx_queue_len = 0;

        /* set up method calls */
        new_dev->change_mtu = vlan_dev_change_mtu;
        new_dev->open = vlan_dev_open;
        new_dev->stop = vlan_dev_stop;
        new_dev->set_mac_address = vlan_dev_set_mac_address;
        new_dev->set_multicast_list = vlan_dev_set_multicast_list;
        new_dev->destructor = free_netdev;
        new_dev->do_ioctl = vlan_dev_ioctl;
}

/*  Attach a VLAN device to a mac address (ie Ethernet Card).
 *  Returns the device that was created, or NULL if there was
 *  an error of some kind.
 */
static struct net_device *register_vlan_device(const char *eth_IF_name,
                                               unsigned short VLAN_ID)
{
        struct vlan_group *grp;
        struct net_device *new_dev;
        struct net_device *real_dev; /* the ethernet device */
        char name[IFNAMSIZ];

#ifdef VLAN_DEBUG
        printk(VLAN_DBG "%s: if_name -:%s:-     vid: %i\n",
                __FUNCTION__, eth_IF_name, VLAN_ID);
#endif

        if (VLAN_ID >= VLAN_VID_MASK)
                goto out_ret_null;

        /* find the device relating to eth_IF_name. */
        real_dev = dev_get_by_name(eth_IF_name);
        if (!real_dev)
                goto out_ret_null;

        if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
                printk(VLAN_DBG "%s: VLANs not supported on %s.\n",
                        __FUNCTION__, real_dev->name);
                goto out_put_dev;
        }

        if ((real_dev->features & NETIF_F_HW_VLAN_RX) &&
            (real_dev->vlan_rx_register == NULL ||
             real_dev->vlan_rx_kill_vid == NULL)) {
                printk(VLAN_DBG "%s: Device %s has buggy VLAN hw accel.\n",
                        __FUNCTION__, real_dev->name);
                goto out_put_dev;
        }

        if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
            (real_dev->vlan_rx_add_vid == NULL ||
             real_dev->vlan_rx_kill_vid == NULL)) {
                printk(VLAN_DBG "%s: Device %s has buggy VLAN hw accel.\n",
                        __FUNCTION__, real_dev->name);
                goto out_put_dev;
        }

        /* From this point on, all the data structures must remain
         * consistent.
         */
        rtnl_lock();

        /* The real device must be up and operating in order to
         * assosciate a VLAN device with it.
         */
        if (!(real_dev->flags & IFF_UP))
                goto out_unlock;

        if (__find_vlan_dev(real_dev, VLAN_ID) != NULL) {
                /* was already registered. */
                printk(VLAN_DBG "%s: ALREADY had VLAN registered\n", __FUNCTION__);
                goto out_unlock;
        }

        /* Gotta set up the fields for the device. */
#ifdef VLAN_DEBUG
        printk(VLAN_DBG "About to allocate name, vlan_name_type: %i\n",
               vlan_name_type);
#endif
        switch (vlan_name_type) {
        case VLAN_NAME_TYPE_RAW_PLUS_VID:
                /* name will look like:  eth1.0005 */
                snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, VLAN_ID);
                break;
        case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
                /* Put our vlan.VID in the name.
                 * Name will look like:  vlan5
                 */
                snprintf(name, IFNAMSIZ, "vlan%i", VLAN_ID);
                break;
        case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
                /* Put our vlan.VID in the name.
                 * Name will look like:  eth0.5
                 */
                snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, VLAN_ID);
                break;
        case VLAN_NAME_TYPE_PLUS_VID:
                /* Put our vlan.VID in the name.
                 * Name will look like:  vlan0005
                 */
        default:
                snprintf(name, IFNAMSIZ, "vlan%.4i", VLAN_ID);
        };
                    
        new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name,
                               vlan_setup);
        if (new_dev == NULL)
                goto out_unlock;

#ifdef VLAN_DEBUG
        printk(VLAN_DBG "Allocated new name -:%s:-\n", new_dev->name);
#endif
        /* IFF_BROADCAST|IFF_MULTICAST; ??? */
        new_dev->flags = real_dev->flags;
        new_dev->flags &= ~IFF_UP;

        new_dev->state = real_dev->state & VLAN_LINK_STATE_MASK;

        /* need 4 bytes for extra VLAN header info,
         * hope the underlying device can handle it.
         */
        new_dev->mtu = real_dev->mtu;

        /* TODO: maybe just assign it to be ETHERNET? */
        new_dev->type = real_dev->type;

        new_dev->hard_header_len = real_dev->hard_header_len;
        if (!(real_dev->features & NETIF_F_HW_VLAN_TX)) {
                /* Regular ethernet + 4 bytes (18 total). */
                new_dev->hard_header_len += VLAN_HLEN;
        }

        VLAN_MEM_DBG("new_dev->priv malloc, addr: %p  size: %i\n",
                     new_dev->priv,
                     sizeof(struct vlan_dev_info));
            
        memcpy(new_dev->broadcast, real_dev->broadcast, real_dev->addr_len);
        memcpy(new_dev->dev_addr, real_dev->dev_addr, real_dev->addr_len);
        new_dev->addr_len = real_dev->addr_len;

        if (real_dev->features & NETIF_F_HW_VLAN_TX) {
                new_dev->hard_header = real_dev->hard_header;
                new_dev->hard_start_xmit = vlan_dev_hwaccel_hard_start_xmit;
                new_dev->rebuild_header = real_dev->rebuild_header;
        } else {
                new_dev->hard_header = vlan_dev_hard_header;
                new_dev->hard_start_xmit = vlan_dev_hard_start_xmit;
                new_dev->rebuild_header = vlan_dev_rebuild_header;
        }
        new_dev->hard_header_parse = real_dev->hard_header_parse;

        VLAN_DEV_INFO(new_dev)->vlan_id = VLAN_ID; /* 1 through VLAN_VID_MASK */
        VLAN_DEV_INFO(new_dev)->real_dev = real_dev;
        VLAN_DEV_INFO(new_dev)->dent = NULL;
        VLAN_DEV_INFO(new_dev)->flags = 1;

#ifdef VLAN_DEBUG
        printk(VLAN_DBG "About to go find the group for idx: %i\n",
               real_dev->ifindex);
#endif
            
        if (register_netdevice(new_dev))
                goto out_free_newdev;

        /* So, got the sucker initialized, now lets place
         * it into our local structure.
         */
        grp = __vlan_find_group(real_dev->ifindex);

        /* Note, we are running under the RTNL semaphore
         * so it cannot "appear" on us.
         */
        if (!grp) { /* need to add a new group */
                grp = kmalloc(sizeof(struct vlan_group), GFP_KERNEL);
                if (!grp)
                        goto out_free_unregister;
                                        
                /* printk(KERN_ALERT "VLAN REGISTER:  Allocated new group.\n"); */
                memset(grp, 0, sizeof(struct vlan_group));
                grp->real_dev_ifindex = real_dev->ifindex;

                hlist_add_head_rcu(&grp->hlist, 
                                   &vlan_group_hash[vlan_grp_hashfn(real_dev->ifindex)]);

                if (real_dev->features & NETIF_F_HW_VLAN_RX)
                        real_dev->vlan_rx_register(real_dev, grp);
        }
            
        grp->vlan_devices[VLAN_ID] = new_dev;

        if (vlan_proc_add_dev(new_dev)<0)/* create it's proc entry */
                printk(KERN_WARNING "VLAN: failed to add proc entry for %s\n",
                                                         new_dev->name);

        if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
                real_dev->vlan_rx_add_vid(real_dev, VLAN_ID);

        rtnl_unlock();


#ifdef VLAN_DEBUG
        printk(VLAN_DBG "Allocated new device successfully, returning.\n");
#endif
        return new_dev;

out_free_unregister:
        unregister_netdev(new_dev);
        goto out_unlock;

out_free_newdev:
        free_netdev(new_dev);

out_unlock:
        rtnl_unlock();

out_put_dev:
        dev_put(real_dev);

out_ret_null:
        return NULL;
}

static int vlan_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
{
        struct net_device *dev = ptr;
        struct vlan_group *grp = __vlan_find_group(dev->ifindex);
        int i, flgs;
        struct net_device *vlandev;

        if (!grp)
                goto out;

        /* It is OK that we do not hold the group lock right now,
         * as we run under the RTNL lock.
         */

        switch (event) {
        case NETDEV_CHANGE:
                /* Propagate real device state to vlan devices */
                flgs = dev->state & VLAN_LINK_STATE_MASK;
                for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
                        vlandev = grp->vlan_devices[i];
                        if (!vlandev)
                                continue;

                        if ((vlandev->state & VLAN_LINK_STATE_MASK) != flgs) {
                                vlandev->state = (vlandev->state &~ VLAN_LINK_STATE_MASK) 
                                        | flgs;
                                netdev_state_change(vlandev);
                        }
                }
                break;

        case NETDEV_DOWN:
                /* Put all VLANs for this dev in the down state too.  */
                for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
                        vlandev = grp->vlan_devices[i];
                        if (!vlandev)
                                continue;

                        flgs = vlandev->flags;
                        if (!(flgs & IFF_UP))
                                continue;

                        dev_change_flags(vlandev, flgs & ~IFF_UP);
                }
                break;

        case NETDEV_UP:
                /* Put all VLANs for this dev in the up state too.  */
                for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
                        vlandev = grp->vlan_devices[i];
                        if (!vlandev)
                                continue;
                                
                        flgs = vlandev->flags;
                        if (flgs & IFF_UP)
                                continue;

                        dev_change_flags(vlandev, flgs | IFF_UP);
                }
                break;
                
        case NETDEV_UNREGISTER:
                /* Delete all VLANs for this dev. */
                for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
                        int ret;

                        vlandev = grp->vlan_devices[i];
                        if (!vlandev)
                                continue;

                        ret = unregister_vlan_dev(dev,
                                                  VLAN_DEV_INFO(vlandev)->vlan_id);

                        unregister_netdevice(vlandev);

                        /* Group was destroyed? */
                        if (ret == 1)
                                break;
                }
                break;
        };

out:
        return NOTIFY_DONE;
}

/*
 *      VLAN IOCTL handler.
 *      o execute requested action or pass command to the device driver
 *   arg is really a struct vlan_ioctl_args __user *.
 */
static int vlan_ioctl_handler(void __user *arg)
{
        int err = 0;
        unsigned short vid = 0;
        struct vlan_ioctl_args args;

        if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
                return -EFAULT;

        /* Null terminate this sucker, just in case. */
        args.device1[23] = 0;
        args.u.device2[23] = 0;

#ifdef VLAN_DEBUG
        printk(VLAN_DBG "%s: args.cmd: %x\n", __FUNCTION__, args.cmd);
#endif

        switch (args.cmd) {
        case SET_VLAN_INGRESS_PRIORITY_CMD:
                if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
                err = vlan_dev_set_ingress_priority(args.device1,
                                                    args.u.skb_priority,
                                                    args.vlan_qos);
                break;

        case SET_VLAN_EGRESS_PRIORITY_CMD:
                if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
                err = vlan_dev_set_egress_priority(args.device1,
                                                   args.u.skb_priority,
                                                   args.vlan_qos);
                break;

        case SET_VLAN_FLAG_CMD:
                if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
                err = vlan_dev_set_vlan_flag(args.device1,
                                             args.u.flag,
                                             args.vlan_qos);
                break;

        case SET_VLAN_NAME_TYPE_CMD:
                if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
                if ((args.u.name_type >= 0) &&
                    (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
                        vlan_name_type = args.u.name_type;
                        err = 0;
                } else {
                        err = -EINVAL;
                }
                break;

        case ADD_VLAN_CMD:
                if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
                /* we have been given the name of the Ethernet Device we want to
                 * talk to:  args.dev1   We also have the
                 * VLAN ID:  args.u.VID
                 */
                if (register_vlan_device(args.device1, args.u.VID)) {
                        err = 0;
                } else {
                        err = -EINVAL;
                }
                break;

        case DEL_VLAN_CMD:
                if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
                /* Here, the args.dev1 is the actual VLAN we want
                 * to get rid of.
                 */
                err = unregister_vlan_device(args.device1);
                break;

        case GET_VLAN_INGRESS_PRIORITY_CMD:
                /* TODO:  Implement
                   err = vlan_dev_get_ingress_priority(args);
                   if (copy_to_user((void*)arg, &args,
                        sizeof(struct vlan_ioctl_args))) {
                        err = -EFAULT;
                   }
                */
                err = -EINVAL;
                break;
        case GET_VLAN_EGRESS_PRIORITY_CMD:
                /* TODO:  Implement
                   err = vlan_dev_get_egress_priority(args.device1, &(args.args);
                   if (copy_to_user((void*)arg, &args,
                        sizeof(struct vlan_ioctl_args))) {
                        err = -EFAULT;
                   }
                */
                err = -EINVAL;
                break;
        case GET_VLAN_REALDEV_NAME_CMD:
                err = vlan_dev_get_realdev_name(args.device1, args.u.device2);
                if (copy_to_user(arg, &args,
                                 sizeof(struct vlan_ioctl_args))) {
                        err = -EFAULT;
                }
                break;

        case GET_VLAN_VID_CMD:
                err = vlan_dev_get_vid(args.device1, &vid);
                args.u.VID = vid;
                if (copy_to_user(arg, &args,
                                 sizeof(struct vlan_ioctl_args))) {
                      err = -EFAULT;
                }
                break;

        default:
                /* pass on to underlying device instead?? */
                printk(VLAN_DBG "%s: Unknown VLAN CMD: %x \n",
                        __FUNCTION__, args.cmd);
                return -EINVAL;
        };

        return err;
}

MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);