[VLAN]: Clean up unregister_vlan_dev

static int unregister_vlan_dev(struct net_device *real_dev,

			       unsigned short vlan_id)

{

	struct net_device *dev = NULL;

	struct net_device *dev;

	int real_dev_ifindex = real_dev->ifindex;

	struct vlan_group *grp;

	int i, ret;

	unsigned int i;

	int ret;

	/* sanity check */

	if (vlan_id >= VLAN_VID_MASK)

		return -EINVAL;

	ASSERT_RTNL();

	grp = __vlan_find_group(real_dev_ifindex);

	if (!grp)

		return -ENOENT;

	ret = 0;

	if (grp) {

	dev = vlan_group_get_device(grp, vlan_id);

		if (dev) {

			/* Remove proc entry */

	if (!dev)

		return -ENOENT;

	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.

	/* 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_FILTER)

		real_dev->vlan_rx_kill_vid(real_dev, vlan_id);

	vlan_group_set_device(grp, vlan_id, NULL);

	synchronize_net();

			/* Caller unregisters (and if necessary, puts)

			 * VLAN device, but we get rid of the reference to

			 * real_dev here.

	/* 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.

			 */

	/* If the group is now empty, kill off the group. */

	ret = 0;

	for (i = 0; i < VLAN_VID_MASK; i++)

		if (vlan_group_get_device(grp, i))

			break;

		/* Free the group, after all cpu's are done. */

		call_rcu(&grp->rcu, vlan_rcu_free);

				grp = NULL;

		ret = 1;

	}

		}

	}

	return ret;

}