drivers/net/macvlan.c - kernel/msm-4.19 - Gitiles

 /*
  * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
  *
  * 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.
  *
  * The code this is based on carried the following copyright notice:
  * ---
  * (C) Copyright 2001-2006
  * Alex Zeffertt, Cambridge Broadband Ltd, ajz@cambridgebroadband.com
  * Re-worked by Ben Greear <greearb@candelatech.com>
  * ---
  */
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/list.h>
 #include <linux/notifier.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/ethtool.h>
 #include <linux/if_arp.h>
 #include <linux/if_link.h>
 #include <linux/if_macvlan.h>
 #include <net/rtnetlink.h>

 #define MACVLAN_HASH_SIZE	(1 << BITS_PER_BYTE)

 struct macvlan_port {
 	struct net_device	*dev;
 	struct hlist_head	vlan_hash[MACVLAN_HASH_SIZE];
 	struct list_head	vlans;
 };

 struct macvlan_dev {
 	struct net_device	*dev;
 	struct list_head	list;
 	struct hlist_node	hlist;
 	struct macvlan_port	*port;
 	struct net_device	*lowerdev;
 };


 static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
 					       const unsigned char *addr)
 {
 	struct macvlan_dev *vlan;
 	struct hlist_node *n;

 	hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
 		if (!compare_ether_addr(vlan->dev->dev_addr, addr))
 			return vlan;
 	}
 	return NULL;
 }

 static void macvlan_broadcast(struct sk_buff *skb,
 			      const struct macvlan_port *port)
 {
 	const struct ethhdr *eth = eth_hdr(skb);
 	const struct macvlan_dev *vlan;
 	struct hlist_node *n;
 	struct net_device *dev;
 	struct sk_buff *nskb;
 	unsigned int i;

 	for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
 		hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
 			dev = vlan->dev;
 			if (unlikely(!(dev->flags & IFF_UP)))
 				continue;

 			nskb = skb_clone(skb, GFP_ATOMIC);
 			if (nskb == NULL) {
 				dev->stats.rx_errors++;
 				dev->stats.rx_dropped++;
 				continue;
 			}

 			dev->stats.rx_bytes += skb->len + ETH_HLEN;
 			dev->stats.rx_packets++;
 			dev->stats.multicast++;
 			dev->last_rx = jiffies;

 			nskb->dev = dev;
 			if (!compare_ether_addr(eth->h_dest, dev->broadcast))
 				nskb->pkt_type = PACKET_BROADCAST;
 			else
 				nskb->pkt_type = PACKET_MULTICAST;

 			netif_rx(nskb);
 		}
 	}
 }

 /* called under rcu_read_lock() from netif_receive_skb */
 static struct sk_buff *macvlan_handle_frame(struct sk_buff *skb)
 {
 	const struct ethhdr *eth = eth_hdr(skb);
 	const struct macvlan_port *port;
 	const struct macvlan_dev *vlan;
 	struct net_device *dev;

 	port = rcu_dereference(skb->dev->macvlan_port);
 	if (port == NULL)
 		return skb;

 	if (is_multicast_ether_addr(eth->h_dest)) {
 		macvlan_broadcast(skb, port);
 		return skb;
 	}

 	vlan = macvlan_hash_lookup(port, eth->h_dest);
 	if (vlan == NULL)
 		return skb;

 	dev = vlan->dev;
 	if (unlikely(!(dev->flags & IFF_UP))) {
 		kfree_skb(skb);
 		return NULL;
 	}

 	skb = skb_share_check(skb, GFP_ATOMIC);
 	if (skb == NULL) {
 		dev->stats.rx_errors++;
 		dev->stats.rx_dropped++;
 		return NULL;
 	}

 	dev->stats.rx_bytes += skb->len + ETH_HLEN;
 	dev->stats.rx_packets++;
 	dev->last_rx = jiffies;

 	skb->dev = dev;
 	skb->pkt_type = PACKET_HOST;

 	netif_rx(skb);
 	return NULL;
 }

 static int macvlan_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	const struct macvlan_dev *vlan = netdev_priv(dev);
 	unsigned int len = skb->len;
 	int ret;

 	skb->dev = vlan->lowerdev;
 	ret = dev_queue_xmit(skb);

 	if (likely(ret == NET_XMIT_SUCCESS)) {
 		dev->stats.tx_packets++;
 		dev->stats.tx_bytes += len;
 	} else {
 		dev->stats.tx_errors++;
 		dev->stats.tx_aborted_errors++;
 	}
 	return NETDEV_TX_OK;
 }

 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
 			       unsigned short type, const void *daddr,
 			       const void *saddr, unsigned len)
 {
 	const struct macvlan_dev *vlan = netdev_priv(dev);
 	struct net_device *lowerdev = vlan->lowerdev;

 	return dev_hard_header(skb, lowerdev, type, daddr,
 			       saddr ? : dev->dev_addr, len);
 }

 static const struct header_ops macvlan_hard_header_ops = {
 	.create  	= macvlan_hard_header,
 	.rebuild	= eth_rebuild_header,
 	.parse		= eth_header_parse,
 	.cache		= eth_header_cache,
 	.cache_update	= eth_header_cache_update,
 };

 static int macvlan_open(struct net_device *dev)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
 	struct macvlan_port *port = vlan->port;
 	struct net_device *lowerdev = vlan->lowerdev;
 	int err;

 	err = dev_unicast_add(lowerdev, dev->dev_addr, ETH_ALEN);
 	if (err < 0)
 		return err;
 	if (dev->flags & IFF_ALLMULTI)
 		dev_set_allmulti(lowerdev, 1);

 	hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[dev->dev_addr[5]]);
 	return 0;
 }

 static int macvlan_stop(struct net_device *dev)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
 	struct net_device *lowerdev = vlan->lowerdev;

 	dev_mc_unsync(lowerdev, dev);
 	if (dev->flags & IFF_ALLMULTI)
 		dev_set_allmulti(lowerdev, -1);

 	dev_unicast_delete(lowerdev, dev->dev_addr, ETH_ALEN);

 	hlist_del_rcu(&vlan->hlist);
 	synchronize_rcu();
 	return 0;
 }

 static void macvlan_change_rx_flags(struct net_device *dev, int change)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
 	struct net_device *lowerdev = vlan->lowerdev;

 	if (change & IFF_ALLMULTI)
 		dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
 }

 static void macvlan_set_multicast_list(struct net_device *dev)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);

 	dev_mc_sync(vlan->lowerdev, dev);
 }

 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);

 	if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
 		return -EINVAL;
 	dev->mtu = new_mtu;
 	return 0;
 }

 /*
  * macvlan network devices have devices nesting below it and are a special
  * "super class" of normal network devices; split their locks off into a
  * separate class since they always nest.
  */
 static struct lock_class_key macvlan_netdev_xmit_lock_key;

 #define MACVLAN_FEATURES \
 	(NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
 	 NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
 	 NETIF_F_TSO_ECN | NETIF_F_TSO6)

 #define MACVLAN_STATE_MASK \
 	((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))

 static int macvlan_init(struct net_device *dev)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
 	const struct net_device *lowerdev = vlan->lowerdev;

 	dev->state		= (dev->state & ~MACVLAN_STATE_MASK) |
 				  (lowerdev->state & MACVLAN_STATE_MASK);
 	dev->features 		= lowerdev->features & MACVLAN_FEATURES;
 	dev->iflink		= lowerdev->ifindex;

 	lockdep_set_class(&dev->_xmit_lock, &macvlan_netdev_xmit_lock_key);
 	return 0;
 }

 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
 					struct ethtool_drvinfo *drvinfo)
 {
 	snprintf(drvinfo->driver, 32, "macvlan");
 	snprintf(drvinfo->version, 32, "0.1");
 }

 static u32 macvlan_ethtool_get_rx_csum(struct net_device *dev)
 {
 	const struct macvlan_dev *vlan = netdev_priv(dev);
 	struct net_device *lowerdev = vlan->lowerdev;

 	if (lowerdev->ethtool_ops->get_rx_csum == NULL)
 		return 0;
 	return lowerdev->ethtool_ops->get_rx_csum(lowerdev);
 }

 static const struct ethtool_ops macvlan_ethtool_ops = {
 	.get_link		= ethtool_op_get_link,
 	.get_rx_csum		= macvlan_ethtool_get_rx_csum,
 	.get_drvinfo		= macvlan_ethtool_get_drvinfo,
 };

 static void macvlan_setup(struct net_device *dev)
 {
 	ether_setup(dev);

 	dev->init		= macvlan_init;
 	dev->open		= macvlan_open;
 	dev->stop		= macvlan_stop;
 	dev->change_mtu		= macvlan_change_mtu;
 	dev->change_rx_flags	= macvlan_change_rx_flags;
 	dev->set_multicast_list	= macvlan_set_multicast_list;
 	dev->hard_start_xmit	= macvlan_hard_start_xmit;
 	dev->destructor		= free_netdev;
 	dev->header_ops		= &macvlan_hard_header_ops,
 	dev->ethtool_ops	= &macvlan_ethtool_ops;
 	dev->tx_queue_len	= 0;
 }

 static int macvlan_port_create(struct net_device *dev)
 {
 	struct macvlan_port *port;
 	unsigned int i;

 	if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
 		return -EINVAL;

 	port = kzalloc(sizeof(*port), GFP_KERNEL);
 	if (port == NULL)
 		return -ENOMEM;

 	port->dev = dev;
 	INIT_LIST_HEAD(&port->vlans);
 	for (i = 0; i < MACVLAN_HASH_SIZE; i++)
 		INIT_HLIST_HEAD(&port->vlan_hash[i]);
 	rcu_assign_pointer(dev->macvlan_port, port);
 	return 0;
 }

 static void macvlan_port_destroy(struct net_device *dev)
 {
 	struct macvlan_port *port = dev->macvlan_port;

 	rcu_assign_pointer(dev->macvlan_port, NULL);
 	synchronize_rcu();
 	kfree(port);
 }

 static void macvlan_transfer_operstate(struct net_device *dev)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
 	const struct net_device *lowerdev = vlan->lowerdev;

 	if (lowerdev->operstate == IF_OPER_DORMANT)
 		netif_dormant_on(dev);
 	else
 		netif_dormant_off(dev);

 	if (netif_carrier_ok(lowerdev)) {
 		if (!netif_carrier_ok(dev))
 			netif_carrier_on(dev);
 	} else {
 		if (netif_carrier_ok(lowerdev))
 			netif_carrier_off(dev);
 	}
 }

 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
 {
 	if (tb[IFLA_ADDRESS]) {
 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 			return -EINVAL;
 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 			return -EADDRNOTAVAIL;
 	}
 	return 0;
 }

 static int macvlan_newlink(struct net_device *dev,
 			   struct nlattr *tb[], struct nlattr *data[])
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
 	struct macvlan_port *port;
 	struct net_device *lowerdev;
 	int err;

 	if (!tb[IFLA_LINK])
 		return -EINVAL;

 	lowerdev = __dev_get_by_index(dev->nd_net, nla_get_u32(tb[IFLA_LINK]));
 	if (lowerdev == NULL)
 		return -ENODEV;

 	/* Don't allow macvlans on top of other macvlans - its not really
 	 * wrong, but lockdep can't handle it and its not useful for anything
 	 * you couldn't do directly on top of the real device.
 	 */
 	if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops)
 		return -ENODEV;

 	if (!tb[IFLA_MTU])
 		dev->mtu = lowerdev->mtu;
 	else if (dev->mtu > lowerdev->mtu)
 		return -EINVAL;

 	if (!tb[IFLA_ADDRESS])
 		random_ether_addr(dev->dev_addr);

 	if (lowerdev->macvlan_port == NULL) {
 		err = macvlan_port_create(lowerdev);
 		if (err < 0)
 			return err;
 	}
 	port = lowerdev->macvlan_port;

 	vlan->lowerdev = lowerdev;
 	vlan->dev      = dev;
 	vlan->port     = port;

 	err = register_netdevice(dev);
 	if (err < 0)
 		return err;

 	list_add_tail(&vlan->list, &port->vlans);
 	macvlan_transfer_operstate(dev);
 	return 0;
 }

 static void macvlan_dellink(struct net_device *dev)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
 	struct macvlan_port *port = vlan->port;

 	list_del(&vlan->list);
 	unregister_netdevice(dev);

 	if (list_empty(&port->vlans))
 		macvlan_port_destroy(dev);
 }

 static struct rtnl_link_ops macvlan_link_ops __read_mostly = {
 	.kind		= "macvlan",
 	.priv_size	= sizeof(struct macvlan_dev),
 	.setup		= macvlan_setup,
 	.validate	= macvlan_validate,
 	.newlink	= macvlan_newlink,
 	.dellink	= macvlan_dellink,
 };

 static int macvlan_device_event(struct notifier_block *unused,
 				unsigned long event, void *ptr)
 {
 	struct net_device *dev = ptr;
 	struct macvlan_dev *vlan, *next;
 	struct macvlan_port *port;

 	port = dev->macvlan_port;
 	if (port == NULL)
 		return NOTIFY_DONE;

 	switch (event) {
 	case NETDEV_CHANGE:
 		list_for_each_entry(vlan, &port->vlans, list)
 			macvlan_transfer_operstate(vlan->dev);
 		break;
 	case NETDEV_FEAT_CHANGE:
 		list_for_each_entry(vlan, &port->vlans, list) {
 			vlan->dev->features = dev->features & MACVLAN_FEATURES;
 			netdev_features_change(vlan->dev);
 		}
 		break;
 	case NETDEV_UNREGISTER:
 		list_for_each_entry_safe(vlan, next, &port->vlans, list)
 			macvlan_dellink(vlan->dev);
 		break;
 	}
 	return NOTIFY_DONE;
 }

 static struct notifier_block macvlan_notifier_block __read_mostly = {
 	.notifier_call	= macvlan_device_event,
 };

 static int __init macvlan_init_module(void)
 {
 	int err;

 	register_netdevice_notifier(&macvlan_notifier_block);
 	macvlan_handle_frame_hook = macvlan_handle_frame;

 	err = rtnl_link_register(&macvlan_link_ops);
 	if (err < 0)
 		goto err1;
 	return 0;
 err1:
 	macvlan_handle_frame_hook = macvlan_handle_frame;
 	unregister_netdevice_notifier(&macvlan_notifier_block);
 	return err;
 }

 static void __exit macvlan_cleanup_module(void)
 {
 	rtnl_link_unregister(&macvlan_link_ops);
 	macvlan_handle_frame_hook = NULL;
 	unregister_netdevice_notifier(&macvlan_notifier_block);
 }

 module_init(macvlan_init_module);
 module_exit(macvlan_cleanup_module);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
 MODULE_ALIAS_RTNL_LINK("macvlan");
	/*
	* Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
	*
	* 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.
	*
	* The code this is based on carried the following copyright notice:
	* ---
	* (C) Copyright 2001-2006
	* Alex Zeffertt, Cambridge Broadband Ltd, ajz@cambridgebroadband.com
	* Re-worked by Ben Greear <greearb@candelatech.com>
	* ---
	*/
	#include <linux/kernel.h>
	#include <linux/types.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/errno.h>
	#include <linux/slab.h>
	#include <linux/string.h>
	#include <linux/list.h>
	#include <linux/notifier.h>
	#include <linux/netdevice.h>
	#include <linux/etherdevice.h>
	#include <linux/ethtool.h>
	#include <linux/if_arp.h>
	#include <linux/if_link.h>
	#include <linux/if_macvlan.h>
	#include <net/rtnetlink.h>

	#define MACVLAN_HASH_SIZE (1 << BITS_PER_BYTE)

	struct macvlan_port {
	struct net_device *dev;
	struct hlist_head vlan_hash[MACVLAN_HASH_SIZE];
	struct list_head vlans;
	};

	struct macvlan_dev {
	struct net_device *dev;
	struct list_head list;
	struct hlist_node hlist;
	struct macvlan_port *port;
	struct net_device *lowerdev;
	};


	static struct macvlan_dev macvlan_hash_lookup(const struct macvlan_port port,
	const unsigned char *addr)
	{
	struct macvlan_dev *vlan;
	struct hlist_node *n;

	hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
	if (!compare_ether_addr(vlan->dev->dev_addr, addr))
	return vlan;
	}
	return NULL;
	}

	static void macvlan_broadcast(struct sk_buff *skb,
	const struct macvlan_port *port)
	{
	const struct ethhdr *eth = eth_hdr(skb);
	const struct macvlan_dev *vlan;
	struct hlist_node *n;
	struct net_device *dev;
	struct sk_buff *nskb;
	unsigned int i;

	for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
	hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
	dev = vlan->dev;
	if (unlikely(!(dev->flags & IFF_UP)))
	continue;

	nskb = skb_clone(skb, GFP_ATOMIC);
	if (nskb == NULL) {
	dev->stats.rx_errors++;
	dev->stats.rx_dropped++;
	continue;
	}

	dev->stats.rx_bytes += skb->len + ETH_HLEN;
	dev->stats.rx_packets++;
	dev->stats.multicast++;
	dev->last_rx = jiffies;

	nskb->dev = dev;
	if (!compare_ether_addr(eth->h_dest, dev->broadcast))
	nskb->pkt_type = PACKET_BROADCAST;
	else
	nskb->pkt_type = PACKET_MULTICAST;

	netif_rx(nskb);
	}
	}
	}

	/* called under rcu_read_lock() from netif_receive_skb */
	static struct sk_buff macvlan_handle_frame(struct sk_buff skb)
	{
	const struct ethhdr *eth = eth_hdr(skb);
	const struct macvlan_port *port;
	const struct macvlan_dev *vlan;
	struct net_device *dev;

	port = rcu_dereference(skb->dev->macvlan_port);
	if (port == NULL)
	return skb;

	if (is_multicast_ether_addr(eth->h_dest)) {
	macvlan_broadcast(skb, port);
	return skb;
	}

	vlan = macvlan_hash_lookup(port, eth->h_dest);
	if (vlan == NULL)
	return skb;

	dev = vlan->dev;
	if (unlikely(!(dev->flags & IFF_UP))) {
	kfree_skb(skb);
	return NULL;
	}

	skb = skb_share_check(skb, GFP_ATOMIC);
	if (skb == NULL) {
	dev->stats.rx_errors++;
	dev->stats.rx_dropped++;
	return NULL;
	}

	dev->stats.rx_bytes += skb->len + ETH_HLEN;
	dev->stats.rx_packets++;
	dev->last_rx = jiffies;

	skb->dev = dev;
	skb->pkt_type = PACKET_HOST;

	netif_rx(skb);
	return NULL;
	}

	static int macvlan_hard_start_xmit(struct sk_buff skb, struct net_device dev)
	{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	unsigned int len = skb->len;
	int ret;

	skb->dev = vlan->lowerdev;
	ret = dev_queue_xmit(skb);

	if (likely(ret == NET_XMIT_SUCCESS)) {
	dev->stats.tx_packets++;
	dev->stats.tx_bytes += len;
	} else {
	dev->stats.tx_errors++;
	dev->stats.tx_aborted_errors++;
	}
	return NETDEV_TX_OK;
	}

	static int macvlan_hard_header(struct sk_buff skb, struct net_device dev,
	unsigned short type, const void *daddr,
	const void *saddr, unsigned len)
	{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	return dev_hard_header(skb, lowerdev, type, daddr,
	saddr ? : dev->dev_addr, len);
	}

	static const struct header_ops macvlan_hard_header_ops = {
	.create = macvlan_hard_header,
	.rebuild = eth_rebuild_header,
	.parse = eth_header_parse,
	.cache = eth_header_cache,
	.cache_update = eth_header_cache_update,
	};

	static int macvlan_open(struct net_device *dev)
	{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct macvlan_port *port = vlan->port;
	struct net_device *lowerdev = vlan->lowerdev;
	int err;

	err = dev_unicast_add(lowerdev, dev->dev_addr, ETH_ALEN);
	if (err < 0)
	return err;
	if (dev->flags & IFF_ALLMULTI)
	dev_set_allmulti(lowerdev, 1);

	hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[dev->dev_addr[5]]);
	return 0;
	}

	static int macvlan_stop(struct net_device *dev)
	{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	dev_mc_unsync(lowerdev, dev);
	if (dev->flags & IFF_ALLMULTI)
	dev_set_allmulti(lowerdev, -1);

	dev_unicast_delete(lowerdev, dev->dev_addr, ETH_ALEN);

	hlist_del_rcu(&vlan->hlist);
	synchronize_rcu();
	return 0;
	}

	static void macvlan_change_rx_flags(struct net_device *dev, int change)
	{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	if (change & IFF_ALLMULTI)
	dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
	}

	static void macvlan_set_multicast_list(struct net_device *dev)
	{
	struct macvlan_dev *vlan = netdev_priv(dev);

	dev_mc_sync(vlan->lowerdev, dev);
	}

	static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
	{
	struct macvlan_dev *vlan = netdev_priv(dev);

	if (new_mtu < 68 \|\| vlan->lowerdev->mtu < new_mtu)
	return -EINVAL;
	dev->mtu = new_mtu;
	return 0;
	}

	/*
	* macvlan network devices have devices nesting below it and are a special
	* "super class" of normal network devices; split their locks off into a
	* separate class since they always nest.
	*/
	static struct lock_class_key macvlan_netdev_xmit_lock_key;

	#define MACVLAN_FEATURES \
	(NETIF_F_SG \| NETIF_F_ALL_CSUM \| NETIF_F_HIGHDMA \| NETIF_F_FRAGLIST \| \
	NETIF_F_GSO \| NETIF_F_TSO \| NETIF_F_UFO \| NETIF_F_GSO_ROBUST \| \
	NETIF_F_TSO_ECN \| NETIF_F_TSO6)

	#define MACVLAN_STATE_MASK \
	((1<<__LINK_STATE_NOCARRIER) \| (1<<__LINK_STATE_DORMANT))

	static int macvlan_init(struct net_device *dev)
	{
	struct macvlan_dev *vlan = netdev_priv(dev);
	const struct net_device *lowerdev = vlan->lowerdev;

	dev->state = (dev->state & ~MACVLAN_STATE_MASK) \|
	(lowerdev->state & MACVLAN_STATE_MASK);
	dev->features = lowerdev->features & MACVLAN_FEATURES;
	dev->iflink = lowerdev->ifindex;

	lockdep_set_class(&dev->_xmit_lock, &macvlan_netdev_xmit_lock_key);
	return 0;
	}

	static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
	struct ethtool_drvinfo *drvinfo)
	{
	snprintf(drvinfo->driver, 32, "macvlan");
	snprintf(drvinfo->version, 32, "0.1");
	}

	static u32 macvlan_ethtool_get_rx_csum(struct net_device *dev)
	{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	if (lowerdev->ethtool_ops->get_rx_csum == NULL)
	return 0;
	return lowerdev->ethtool_ops->get_rx_csum(lowerdev);
	}

	static const struct ethtool_ops macvlan_ethtool_ops = {
	.get_link = ethtool_op_get_link,
	.get_rx_csum = macvlan_ethtool_get_rx_csum,
	.get_drvinfo = macvlan_ethtool_get_drvinfo,
	};

	static void macvlan_setup(struct net_device *dev)
	{
	ether_setup(dev);

	dev->init = macvlan_init;
	dev->open = macvlan_open;
	dev->stop = macvlan_stop;
	dev->change_mtu = macvlan_change_mtu;
	dev->change_rx_flags = macvlan_change_rx_flags;
	dev->set_multicast_list = macvlan_set_multicast_list;
	dev->hard_start_xmit = macvlan_hard_start_xmit;
	dev->destructor = free_netdev;
	dev->header_ops = &macvlan_hard_header_ops,
	dev->ethtool_ops = &macvlan_ethtool_ops;
	dev->tx_queue_len = 0;
	}

	static int macvlan_port_create(struct net_device *dev)
	{
	struct macvlan_port *port;
	unsigned int i;

	if (dev->type != ARPHRD_ETHER \|\| dev->flags & IFF_LOOPBACK)
	return -EINVAL;

	port = kzalloc(sizeof(*port), GFP_KERNEL);
	if (port == NULL)
	return -ENOMEM;

	port->dev = dev;
	INIT_LIST_HEAD(&port->vlans);
	for (i = 0; i < MACVLAN_HASH_SIZE; i++)
	INIT_HLIST_HEAD(&port->vlan_hash[i]);
	rcu_assign_pointer(dev->macvlan_port, port);
	return 0;
	}

	static void macvlan_port_destroy(struct net_device *dev)
	{
	struct macvlan_port *port = dev->macvlan_port;

	rcu_assign_pointer(dev->macvlan_port, NULL);
	synchronize_rcu();
	kfree(port);
	}

	static void macvlan_transfer_operstate(struct net_device *dev)
	{
	struct macvlan_dev *vlan = netdev_priv(dev);
	const struct net_device *lowerdev = vlan->lowerdev;

	if (lowerdev->operstate == IF_OPER_DORMANT)
	netif_dormant_on(dev);
	else
	netif_dormant_off(dev);

	if (netif_carrier_ok(lowerdev)) {
	if (!netif_carrier_ok(dev))
	netif_carrier_on(dev);
	} else {
	if (netif_carrier_ok(lowerdev))
	netif_carrier_off(dev);
	}
	}

	static int macvlan_validate(struct nlattr tb[], struct nlattr data[])
	{
	if (tb[IFLA_ADDRESS]) {
	if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
	return -EINVAL;
	if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
	return -EADDRNOTAVAIL;
	}
	return 0;
	}

	static int macvlan_newlink(struct net_device *dev,
	struct nlattr tb[], struct nlattr data[])
	{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct macvlan_port *port;
	struct net_device *lowerdev;
	int err;

	if (!tb[IFLA_LINK])
	return -EINVAL;

	lowerdev = __dev_get_by_index(dev->nd_net, nla_get_u32(tb[IFLA_LINK]));
	if (lowerdev == NULL)
	return -ENODEV;

	/* Don't allow macvlans on top of other macvlans - its not really
	* wrong, but lockdep can't handle it and its not useful for anything
	* you couldn't do directly on top of the real device.
	*/
	if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops)
	return -ENODEV;

	if (!tb[IFLA_MTU])
	dev->mtu = lowerdev->mtu;
	else if (dev->mtu > lowerdev->mtu)
	return -EINVAL;

	if (!tb[IFLA_ADDRESS])
	random_ether_addr(dev->dev_addr);

	if (lowerdev->macvlan_port == NULL) {
	err = macvlan_port_create(lowerdev);
	if (err < 0)
	return err;
	}
	port = lowerdev->macvlan_port;

	vlan->lowerdev = lowerdev;
	vlan->dev = dev;
	vlan->port = port;

	err = register_netdevice(dev);
	if (err < 0)
	return err;

	list_add_tail(&vlan->list, &port->vlans);
	macvlan_transfer_operstate(dev);
	return 0;
	}

	static void macvlan_dellink(struct net_device *dev)
	{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct macvlan_port *port = vlan->port;

	list_del(&vlan->list);
	unregister_netdevice(dev);

	if (list_empty(&port->vlans))
	macvlan_port_destroy(dev);
	}

	static struct rtnl_link_ops macvlan_link_ops __read_mostly = {
	.kind = "macvlan",
	.priv_size = sizeof(struct macvlan_dev),
	.setup = macvlan_setup,
	.validate = macvlan_validate,
	.newlink = macvlan_newlink,
	.dellink = macvlan_dellink,
	};

	static int macvlan_device_event(struct notifier_block *unused,
	unsigned long event, void *ptr)
	{
	struct net_device *dev = ptr;
	struct macvlan_dev vlan, next;
	struct macvlan_port *port;

	port = dev->macvlan_port;
	if (port == NULL)
	return NOTIFY_DONE;

	switch (event) {
	case NETDEV_CHANGE:
	list_for_each_entry(vlan, &port->vlans, list)
	macvlan_transfer_operstate(vlan->dev);
	break;
	case NETDEV_FEAT_CHANGE:
	list_for_each_entry(vlan, &port->vlans, list) {
	vlan->dev->features = dev->features & MACVLAN_FEATURES;
	netdev_features_change(vlan->dev);
	}
	break;
	case NETDEV_UNREGISTER:
	list_for_each_entry_safe(vlan, next, &port->vlans, list)
	macvlan_dellink(vlan->dev);
	break;
	}
	return NOTIFY_DONE;
	}

	static struct notifier_block macvlan_notifier_block __read_mostly = {
	.notifier_call = macvlan_device_event,
	};

	static int __init macvlan_init_module(void)
	{
	int err;

	register_netdevice_notifier(&macvlan_notifier_block);
	macvlan_handle_frame_hook = macvlan_handle_frame;

	err = rtnl_link_register(&macvlan_link_ops);
	if (err < 0)
	goto err1;
	return 0;
	err1:
	macvlan_handle_frame_hook = macvlan_handle_frame;
	unregister_netdevice_notifier(&macvlan_notifier_block);
	return err;
	}

	static void __exit macvlan_cleanup_module(void)
	{
	rtnl_link_unregister(&macvlan_link_ops);
	macvlan_handle_frame_hook = NULL;
	unregister_netdevice_notifier(&macvlan_notifier_block);
	}

	module_init(macvlan_init_module);
	module_exit(macvlan_cleanup_module);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
	MODULE_DESCRIPTION("Driver for MAC address based VLANs");
	MODULE_ALIAS_RTNL_LINK("macvlan");