text: // SPDX-License-Identifier: GPL-2.0-or-later
  /* -*- linux-c -*-
   * INET		802.1Q VLAN
   *		Ethernet-type device handling.
   *
   * Authors:	Ben Greear <greearb@candelatech.com>
   *              Please send support related email to: netdev@vger.kernel.org
   *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
   *
   * Fixes:       Mar 22 2001: Martin Bokaemper <mbokaemper@unispherenetworks.com>
   *                - reset skb->pkt_type on incoming packets when MAC was changed
   *                - see that changed MAC is saddr for outgoing packets
   *              Oct 20, 2001:  Ard van Breeman:
   *                - Fix MC-list, finally.
   *                - Flush MC-list on VLAN destroy.
   */
  
  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/skbuff.h>
  #include <linux/netdevice.h>
  #include <linux/net_tstamp.h>
  #include <linux/etherdevice.h>
  #include <linux/ethtool.h>
  #include <linux/phy.h>
  #include <net/arp.h>
  
  #include "vlan.h"
  #include "vlanproc.h"
  #include <linux/if_vlan.h>
  #include <linux/netpoll.h>
  
  /*
   *	Create the VLAN header for an arbitrary protocol layer
   *
   *	saddr=NULL	means use device source address
   *	daddr=NULL	means leave destination address (eg unresolved arp)
   *
   *  This is called when the SKB is moving down the stack towards the
   *  physical devices.
   */
  static int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
  				unsigned short type,
  				const void *daddr, const void *saddr,
  				unsigned int len)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	struct vlan_hdr *vhdr;
  	unsigned int vhdrlen = 0;
  	u16 vlan_tci = 0;
  	int rc;
  
  	if (!(vlan->flags & VLAN_FLAG_REORDER_HDR)) {
  		vhdr = skb_push(skb, VLAN_HLEN);
  
  		vlan_tci = vlan->vlan_id;
  		vlan_tci |= vlan_dev_get_egress_qos_mask(dev, skb->priority);
  		vhdr->h_vlan_TCI = htons(vlan_tci);
  
  		/*
  		 *  Set the protocol type. For a packet of type ETH_P_802_3/2 we
  		 *  put the length in here instead.
  		 */
  		if (type != ETH_P_802_3 && type != ETH_P_802_2)
  			vhdr->h_vlan_encapsulated_proto = htons(type);
  		else
  			vhdr->h_vlan_encapsulated_proto = htons(len);
  
  		skb->protocol = vlan->vlan_proto;
  		type = ntohs(vlan->vlan_proto);
  		vhdrlen = VLAN_HLEN;
  	}
  
  	/* Before delegating work to the lower layer, enter our MAC-address */
  	if (saddr == NULL)
  		saddr = dev->dev_addr;
  
  	/* Now make the underlying real hard header */
  	dev = vlan->real_dev;
  	rc = dev_hard_header(skb, dev, type, daddr, saddr, len + vhdrlen);
  	if (rc > 0)
  		rc += vhdrlen;
  	return rc;
  }
  
  static inline netdev_tx_t vlan_netpoll_send_skb(struct vlan_dev_priv *vlan, struct sk_buff *skb)
  {
  #ifdef CONFIG_NET_POLL_CONTROLLER
  	return netpoll_send_skb(vlan->netpoll, skb);
  #else
  	BUG();
  	return NETDEV_TX_OK;
  #endif
  }
  
  static netdev_tx_t vlan_dev_hard_start_xmit(struct sk_buff *skb,
  					    struct net_device *dev)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
  	unsigned int len;
  	int ret;
  
  	/* Handle non-VLAN frames if they are sent to us, for example by DHCP.
  	 *
  	 * NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING
  	 * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
  	 */
  	if (veth->h_vlan_proto != vlan->vlan_proto ||
  	    vlan->flags & VLAN_FLAG_REORDER_HDR) {
  		u16 vlan_tci;
  		vlan_tci = vlan->vlan_id;
  		vlan_tci |= vlan_dev_get_egress_qos_mask(dev, skb->priority);
  		__vlan_hwaccel_put_tag(skb, vlan->vlan_proto, vlan_tci);
  	}
  
  	skb->dev = vlan->real_dev;
  	len = skb->len;
  	if (unlikely(netpoll_tx_running(dev)))
  		return vlan_netpoll_send_skb(vlan, skb);
  
  	ret = dev_queue_xmit(skb);
  
  	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
  		struct vlan_pcpu_stats *stats;
  
  		stats = this_cpu_ptr(vlan->vlan_pcpu_stats);
  		u64_stats_update_begin(&stats->syncp);
  		stats->tx_packets++;
  		stats->tx_bytes += len;
  		u64_stats_update_end(&stats->syncp);
  	} else {
  		this_cpu_inc(vlan->vlan_pcpu_stats->tx_dropped);
  	}
  
  	return ret;
  }
  
  static int vlan_dev_change_mtu(struct net_device *dev, int new_mtu)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	unsigned int max_mtu = real_dev->mtu;
  
  	if (netif_reduces_vlan_mtu(real_dev))
  		max_mtu -= VLAN_HLEN;
  	if (max_mtu < new_mtu)
  		return -ERANGE;
  
  	dev->mtu = new_mtu;
  
  	return 0;
  }
  
  void vlan_dev_set_ingress_priority(const struct net_device *dev,
  				   u32 skb_prio, u16 vlan_prio)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  
  	if (vlan->ingress_priority_map[vlan_prio & 0x7] && !skb_prio)
  		vlan->nr_ingress_mappings--;
  	else if (!vlan->ingress_priority_map[vlan_prio & 0x7] && skb_prio)
  		vlan->nr_ingress_mappings++;
  
  	vlan->ingress_priority_map[vlan_prio & 0x7] = skb_prio;
  }
  
  int vlan_dev_set_egress_priority(const struct net_device *dev,
  				 u32 skb_prio, u16 vlan_prio)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	struct vlan_priority_tci_mapping *mp = NULL;
  	struct vlan_priority_tci_mapping *np;
  	u32 vlan_qos = (vlan_prio << VLAN_PRIO_SHIFT) & VLAN_PRIO_MASK;
  
  	/* See if a priority mapping exists.. */
  	mp = vlan->egress_priority_map[skb_prio & 0xF];
  	while (mp) {
  		if (mp->priority == skb_prio) {
  			if (mp->vlan_qos && !vlan_qos)
  				vlan->nr_egress_mappings--;
  			else if (!mp->vlan_qos && vlan_qos)
  				vlan->nr_egress_mappings++;
  			mp->vlan_qos = vlan_qos;
  			return 0;
  		}
  		mp = mp->next;
  	}
  
  	/* Create a new mapping then. */
  	mp = vlan->egress_priority_map[skb_prio & 0xF];
  	np = kmalloc(sizeof(struct vlan_priority_tci_mapping), GFP_KERNEL);
  	if (!np)
  		return -ENOBUFS;
  
  	np->next = mp;
  	np->priority = skb_prio;
  	np->vlan_qos = vlan_qos;
  	/* Before inserting this element in hash table, make sure all its fields
  	 * are committed to memory.
  	 * coupled with smp_rmb() in vlan_dev_get_egress_qos_mask()
  	 */
  	smp_wmb();
  	vlan->egress_priority_map[skb_prio & 0xF] = np;
  	if (vlan_qos)
  		vlan->nr_egress_mappings++;
  	return 0;
  }
  
  /* Flags are defined in the vlan_flags enum in
   * include/uapi/linux/if_vlan.h file.
   */
  int vlan_dev_change_flags(const struct net_device *dev, u32 flags, u32 mask)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	u32 old_flags = vlan->flags;
  
  	if (mask & ~(VLAN_FLAG_REORDER_HDR | VLAN_FLAG_GVRP |
  		     VLAN_FLAG_LOOSE_BINDING | VLAN_FLAG_MVRP |
  		     VLAN_FLAG_BRIDGE_BINDING))
  		return -EINVAL;
  
  	vlan->flags = (old_flags & ~mask) | (flags & mask);
  
  	if (netif_running(dev) && (vlan->flags ^ old_flags) & VLAN_FLAG_GVRP) {
  		if (vlan->flags & VLAN_FLAG_GVRP)
  			vlan_gvrp_request_join(dev);
  		else
  			vlan_gvrp_request_leave(dev);
  	}
  
  	if (netif_running(dev) && (vlan->flags ^ old_flags) & VLAN_FLAG_MVRP) {
  		if (vlan->flags & VLAN_FLAG_MVRP)
  			vlan_mvrp_request_join(dev);
  		else
  			vlan_mvrp_request_leave(dev);
  	}
  	return 0;
  }
  
  void vlan_dev_get_realdev_name(const struct net_device *dev, char *result, size_t size)
  {
  	strscpy_pad(result, vlan_dev_priv(dev)->real_dev->name, size);
  }
  
  bool vlan_dev_inherit_address(struct net_device *dev,
  			      struct net_device *real_dev)
  {
  	if (dev->addr_assign_type != NET_ADDR_STOLEN)
  		return false;
  
  	eth_hw_addr_set(dev, real_dev->dev_addr);
  	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
  	return true;
  }
  
  static int vlan_dev_open(struct net_device *dev)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	struct net_device *real_dev = vlan->real_dev;
  	int err;
  
  	if (!(real_dev->flags & IFF_UP) &&
  	    !(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
  		return -ENETDOWN;
  
  	if (!ether_addr_equal(dev->dev_addr, real_dev->dev_addr) &&
  	    !vlan_dev_inherit_address(dev, real_dev)) {
  		err = dev_uc_add(real_dev, dev->dev_addr);
  		if (err < 0)
  			goto out;
  	}
  
  	if (dev->flags & IFF_ALLMULTI) {
  		err = dev_set_allmulti(real_dev, 1);
  		if (err < 0)
  			goto del_unicast;
  	}
  	if (dev->flags & IFF_PROMISC) {
  		err = dev_set_promiscuity(real_dev, 1);
  		if (err < 0)
  			goto clear_allmulti;
  	}
  
  	ether_addr_copy(vlan->real_dev_addr, real_dev->dev_addr);
  
  	if (vlan->flags & VLAN_FLAG_GVRP)
  		vlan_gvrp_request_join(dev);
  
  	if (vlan->flags & VLAN_FLAG_MVRP)
  		vlan_mvrp_request_join(dev);
  
  	if (netif_carrier_ok(real_dev) &&
  	    !(vlan->flags & VLAN_FLAG_BRIDGE_BINDING))
  		netif_carrier_on(dev);
  	return 0;
  
  clear_allmulti:
  	if (dev->flags & IFF_ALLMULTI)
  		dev_set_allmulti(real_dev, -1);
  del_unicast:
  	if (!ether_addr_equal(dev->dev_addr, real_dev->dev_addr))
  		dev_uc_del(real_dev, dev->dev_addr);
  out:
  	netif_carrier_off(dev);
  	return err;
  }
  
  static int vlan_dev_stop(struct net_device *dev)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	struct net_device *real_dev = vlan->real_dev;
  
  	dev_mc_unsync(real_dev, dev);
  	dev_uc_unsync(real_dev, dev);
  	if (dev->flags & IFF_ALLMULTI)
  		dev_set_allmulti(real_dev, -1);
  	if (dev->flags & IFF_PROMISC)
  		dev_set_promiscuity(real_dev, -1);
  
  	if (!ether_addr_equal(dev->dev_addr, real_dev->dev_addr))
  		dev_uc_del(real_dev, dev->dev_addr);
  
  	if (!(vlan->flags & VLAN_FLAG_BRIDGE_BINDING))
  		netif_carrier_off(dev);
  	return 0;
  }
  
  static int vlan_dev_set_mac_address(struct net_device *dev, void *p)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	struct sockaddr *addr = p;
  	int err;
  
  	if (!is_valid_ether_addr(addr->sa_data))
  		return -EADDRNOTAVAIL;
  
  	if (!(dev->flags & IFF_UP))
  		goto out;
  
  	if (!ether_addr_equal(addr->sa_data, real_dev->dev_addr)) {
  		err = dev_uc_add(real_dev, addr->sa_data);
  		if (err < 0)
  			return err;
  	}
  
  	if (!ether_addr_equal(dev->dev_addr, real_dev->dev_addr))
  		dev_uc_del(real_dev, dev->dev_addr);
  
  out:
  	eth_hw_addr_set(dev, addr->sa_data);
  	return 0;
  }
  
  static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	const struct net_device_ops *ops = real_dev->netdev_ops;
  	struct ifreq ifrr;
  	int err = -EOPNOTSUPP;
  
  	strscpy_pad(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
  	ifrr.ifr_ifru = ifr->ifr_ifru;
  
  	switch (cmd) {
  	case SIOCSHWTSTAMP:
  		if (!net_eq(dev_net(dev), &init_net))
  			break;
  		fallthrough;
  	case SIOCGMIIPHY:
  	case SIOCGMIIREG:
  	case SIOCSMIIREG:
  	case SIOCGHWTSTAMP:
  		if (netif_device_present(real_dev) && ops->ndo_eth_ioctl)
  			err = ops->ndo_eth_ioctl(real_dev, &ifrr, cmd);
  		break;
  	}
  
  	if (!err)
  		ifr->ifr_ifru = ifrr.ifr_ifru;
  
  	return err;
  }
  
  static int vlan_dev_neigh_setup(struct net_device *dev, struct neigh_parms *pa)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	const struct net_device_ops *ops = real_dev->netdev_ops;
  	int err = 0;
  
  	if (netif_device_present(real_dev) && ops->ndo_neigh_setup)
  		err = ops->ndo_neigh_setup(real_dev, pa);
  
  	return err;
  }
  
  #if IS_ENABLED(CONFIG_FCOE)
  static int vlan_dev_fcoe_ddp_setup(struct net_device *dev, u16 xid,
  				   struct scatterlist *sgl, unsigned int sgc)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	const struct net_device_ops *ops = real_dev->netdev_ops;
  	int rc = 0;
  
  	if (ops->ndo_fcoe_ddp_setup)
  		rc = ops->ndo_fcoe_ddp_setup(real_dev, xid, sgl, sgc);
  
  	return rc;
  }
  
  static int vlan_dev_fcoe_ddp_done(struct net_device *dev, u16 xid)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	const struct net_device_ops *ops = real_dev->netdev_ops;
  	int len = 0;
  
  	if (ops->ndo_fcoe_ddp_done)
  		len = ops->ndo_fcoe_ddp_done(real_dev, xid);
  
  	return len;
  }
  
  static int vlan_dev_fcoe_enable(struct net_device *dev)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	const struct net_device_ops *ops = real_dev->netdev_ops;
  	int rc = -EINVAL;
  
  	if (ops->ndo_fcoe_enable)
  		rc = ops->ndo_fcoe_enable(real_dev);
  	return rc;
  }
  
  static int vlan_dev_fcoe_disable(struct net_device *dev)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	const struct net_device_ops *ops = real_dev->netdev_ops;
  	int rc = -EINVAL;
  
  	if (ops->ndo_fcoe_disable)
  		rc = ops->ndo_fcoe_disable(real_dev);
  	return rc;
  }
  
  static int vlan_dev_fcoe_ddp_target(struct net_device *dev, u16 xid,
  				    struct scatterlist *sgl, unsigned int sgc)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	const struct net_device_ops *ops = real_dev->netdev_ops;
  	int rc = 0;
  
  	if (ops->ndo_fcoe_ddp_target)
  		rc = ops->ndo_fcoe_ddp_target(real_dev, xid, sgl, sgc);
  
  	return rc;
  }
  #endif
  
  #ifdef NETDEV_FCOE_WWNN
  static int vlan_dev_fcoe_get_wwn(struct net_device *dev, u64 *wwn, int type)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	const struct net_device_ops *ops = real_dev->netdev_ops;
  	int rc = -EINVAL;
  
  	if (ops->ndo_fcoe_get_wwn)
  		rc = ops->ndo_fcoe_get_wwn(real_dev, wwn, type);
  	return rc;
  }
  #endif
  
  static void vlan_dev_change_rx_flags(struct net_device *dev, int change)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  
  	if (dev->flags & IFF_UP) {
  		if (change & IFF_ALLMULTI)
  			dev_set_allmulti(real_dev, dev->flags & IFF_ALLMULTI ? 1 : -1);
  		if (change & IFF_PROMISC)
  			dev_set_promiscuity(real_dev, dev->flags & IFF_PROMISC ? 1 : -1);
  	}
  }
  
  static void vlan_dev_set_rx_mode(struct net_device *vlan_dev)
  {
  	dev_mc_sync(vlan_dev_priv(vlan_dev)->real_dev, vlan_dev);
  	dev_uc_sync(vlan_dev_priv(vlan_dev)->real_dev, vlan_dev);
  }
  
  /*
   * vlan 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 vlan_netdev_xmit_lock_key;
  static struct lock_class_key vlan_netdev_addr_lock_key;
  
  static void vlan_dev_set_lockdep_one(struct net_device *dev,
  				     struct netdev_queue *txq,
  				     void *unused)
  {
  	lockdep_set_class(&txq->_xmit_lock, &vlan_netdev_xmit_lock_key);
  }
  
  static void vlan_dev_set_lockdep_class(struct net_device *dev)
  {
  	lockdep_set_class(&dev->addr_list_lock,
  			  &vlan_netdev_addr_lock_key);
  	netdev_for_each_tx_queue(dev, vlan_dev_set_lockdep_one, NULL);
  }
  
  static __be16 vlan_parse_protocol(const struct sk_buff *skb)
  {
  	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
  
  	return __vlan_get_protocol(skb, veth->h_vlan_proto, NULL);
  }
  
  static const struct header_ops vlan_header_ops = {
  	.create	 = vlan_dev_hard_header,
  	.parse	 = eth_header_parse,
  	.parse_protocol = vlan_parse_protocol,
  };
  
  static int vlan_passthru_hard_header(struct sk_buff *skb, struct net_device *dev,
  				     unsigned short type,
  				     const void *daddr, const void *saddr,
  				     unsigned int len)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	struct net_device *real_dev = vlan->real_dev;
  
  	if (saddr == NULL)
  		saddr = dev->dev_addr;
  
  	return dev_hard_header(skb, real_dev, type, daddr, saddr, len);
  }
  
  static const struct header_ops vlan_passthru_header_ops = {
  	.create	 = vlan_passthru_hard_header,
  	.parse	 = eth_header_parse,
  	.parse_protocol = vlan_parse_protocol,
  };
  
  static struct device_type vlan_type = {
  	.name	= "vlan",
  };
  
  static const struct net_device_ops vlan_netdev_ops;
  
  static int vlan_dev_init(struct net_device *dev)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	struct net_device *real_dev = vlan->real_dev;
  
  	netif_carrier_off(dev);
  
  	/* IFF_BROADCAST|IFF_MULTICAST; ??? */
  	dev->flags  = real_dev->flags & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI |
  					  IFF_MASTER | IFF_SLAVE);
  	dev->state  = (real_dev->state & ((1<<__LINK_STATE_NOCARRIER) |
  					  (1<<__LINK_STATE_DORMANT))) |
  		      (1<<__LINK_STATE_PRESENT);
  
  	if (vlan->flags & VLAN_FLAG_BRIDGE_BINDING)
  		dev->state |= (1 << __LINK_STATE_NOCARRIER);
  
  	dev->hw_features = NETIF_F_HW_CSUM | NETIF_F_SG |
  			   NETIF_F_FRAGLIST | NETIF_F_GSO_SOFTWARE |
  			   NETIF_F_GSO_ENCAP_ALL |
  			   NETIF_F_HIGHDMA | NETIF_F_SCTP_CRC |
  			   NETIF_F_ALL_FCOE;
  
  	dev->features |= dev->hw_features | NETIF_F_LLTX;
  	netif_set_gso_max_size(dev, real_dev->gso_max_size);
  	netif_set_gso_max_segs(dev, real_dev->gso_max_segs);
  	if (dev->features & NETIF_F_VLAN_FEATURES)
  		netdev_warn(real_dev, "VLAN features are set incorrectly.  Q-in-Q configurations may not work correctly.\n");
  
  	dev->vlan_features = real_dev->vlan_features & ~NETIF_F_ALL_FCOE;
  	dev->hw_enc_features = vlan_tnl_features(real_dev);
  	dev->mpls_features = real_dev->mpls_features;
  
  	/* ipv6 shared card related stuff */
  	dev->dev_id = real_dev->dev_id;
  
  	if (is_zero_ether_addr(dev->dev_addr)) {
  		eth_hw_addr_set(dev, real_dev->dev_addr);
  		dev->addr_assign_type = NET_ADDR_STOLEN;
  	}
  	if (is_zero_ether_addr(dev->broadcast))
  		memcpy(dev->broadcast, real_dev->broadcast, dev->addr_len);
  
  #if IS_ENABLED(CONFIG_FCOE)
  	dev->fcoe_ddp_xid = real_dev->fcoe_ddp_xid;
  #endif
  
  	dev->needed_headroom = real_dev->needed_headroom;
  	if (vlan_hw_offload_capable(real_dev->features, vlan->vlan_proto)) {
  		dev->header_ops      = &vlan_passthru_header_ops;
  		dev->hard_header_len = real_dev->hard_header_len;
  	} else {
  		dev->header_ops      = &vlan_header_ops;
  		dev->hard_header_len = real_dev->hard_header_len + VLAN_HLEN;
  	}
  
  	dev->netdev_ops = &vlan_netdev_ops;
  
  	SET_NETDEV_DEVTYPE(dev, &vlan_type);
  
  	vlan_dev_set_lockdep_class(dev);
  
  	vlan->vlan_pcpu_stats = netdev_alloc_pcpu_stats(struct vlan_pcpu_stats);
  	if (!vlan->vlan_pcpu_stats)
  		return -ENOMEM;
  
  	/* Get vlan's reference to real_dev */
  	dev_hold_track(real_dev, &vlan->dev_tracker, GFP_KERNEL);
  
  	return 0;
  }
  
  /* Note: this function might be called multiple times for the same device. */
  void vlan_dev_free_egress_priority(const struct net_device *dev)
  {
  	struct vlan_priority_tci_mapping *pm;
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(vlan->egress_priority_map); i++) {
  		while ((pm = vlan->egress_priority_map[i]) != NULL) {
  			vlan->egress_priority_map[i] = pm->next;
  			kfree(pm);
  		}
  	}
  }
  
  static void vlan_dev_uninit(struct net_device *dev)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  
  	vlan_dev_free_egress_priority(dev);
  
  	/* Get rid of the vlan's reference to real_dev */
  	dev_put_track(vlan->real_dev, &vlan->dev_tracker);
  }
  
  static netdev_features_t vlan_dev_fix_features(struct net_device *dev,
  	netdev_features_t features)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  	netdev_features_t old_features = features;
  	netdev_features_t lower_features;
  
  	lower_features = netdev_intersect_features((real_dev->vlan_features |
  						    NETIF_F_RXCSUM),
  						   real_dev->features);
  
  	/* Add HW_CSUM setting to preserve user ability to control
  	 * checksum offload on the vlan device.
  	 */
  	if (lower_features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
  		lower_features |= NETIF_F_HW_CSUM;
  	features = netdev_intersect_features(features, lower_features);
  	features |= old_features & (NETIF_F_SOFT_FEATURES | NETIF_F_GSO_SOFTWARE);
  	features |= NETIF_F_LLTX;
  
  	return features;
  }
  
  static int vlan_ethtool_get_link_ksettings(struct net_device *dev,
  					   struct ethtool_link_ksettings *cmd)
  {
  	const struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  
  	return __ethtool_get_link_ksettings(vlan->real_dev, cmd);
  }
  
  static void vlan_ethtool_get_drvinfo(struct net_device *dev,
  				     struct ethtool_drvinfo *info)
  {
  	strlcpy(info->driver, vlan_fullname, sizeof(info->driver));
  	strlcpy(info->version, vlan_version, sizeof(info->version));
  	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
  }
  
  static int vlan_ethtool_get_ts_info(struct net_device *dev,
  				    struct ethtool_ts_info *info)
  {
  	const struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	const struct ethtool_ops *ops = vlan->real_dev->ethtool_ops;
  	struct phy_device *phydev = vlan->real_dev->phydev;
  
  	if (phy_has_tsinfo(phydev)) {
  		return phy_ts_info(phydev, info);
  	} else if (ops->get_ts_info) {
  		return ops->get_ts_info(vlan->real_dev, info);
  	} else {
  		info->so_timestamping = SOF_TIMESTAMPING_RX_SOFTWARE |
  			SOF_TIMESTAMPING_SOFTWARE;
  		info->phc_index = -1;
  	}
  
  	return 0;
  }
  
  static void vlan_dev_get_stats64(struct net_device *dev,
  				 struct rtnl_link_stats64 *stats)
  {
  	struct vlan_pcpu_stats *p;
  	u32 rx_errors = 0, tx_dropped = 0;
  	int i;
  
  	for_each_possible_cpu(i) {
  		u64 rxpackets, rxbytes, rxmulticast, txpackets, txbytes;
  		unsigned int start;
  
  		p = per_cpu_ptr(vlan_dev_priv(dev)->vlan_pcpu_stats, i);
  		do {
  			start = u64_stats_fetch_begin_irq(&p->syncp);
  			rxpackets	= p->rx_packets;
  			rxbytes		= p->rx_bytes;
  			rxmulticast	= p->rx_multicast;
  			txpackets	= p->tx_packets;
  			txbytes		= p->tx_bytes;
  		} while (u64_stats_fetch_retry_irq(&p->syncp, start));
  
  		stats->rx_packets	+= rxpackets;
  		stats->rx_bytes		+= rxbytes;
  		stats->multicast	+= rxmulticast;
  		stats->tx_packets	+= txpackets;
  		stats->tx_bytes		+= txbytes;
  		/* rx_errors & tx_dropped are u32 */
  		rx_errors	+= p->rx_errors;
  		tx_dropped	+= p->tx_dropped;
  	}
  	stats->rx_errors  = rx_errors;
  	stats->tx_dropped = tx_dropped;
  }
  
  #ifdef CONFIG_NET_POLL_CONTROLLER
  static void vlan_dev_poll_controller(struct net_device *dev)
  {
  	return;
  }
  
  static int vlan_dev_netpoll_setup(struct net_device *dev, struct netpoll_info *npinfo)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  	struct net_device *real_dev = vlan->real_dev;
  	struct netpoll *netpoll;
  	int err = 0;
  
  	netpoll = kzalloc(sizeof(*netpoll), GFP_KERNEL);
  	err = -ENOMEM;
  	if (!netpoll)
  		goto out;
  
  	err = __netpoll_setup(netpoll, real_dev);
  	if (err) {
  		kfree(netpoll);
  		goto out;
  	}
  
  	vlan->netpoll = netpoll;
  
  out:
  	return err;
  }
  
  static void vlan_dev_netpoll_cleanup(struct net_device *dev)
  {
  	struct vlan_dev_priv *vlan= vlan_dev_priv(dev);
  	struct netpoll *netpoll = vlan->netpoll;
  
  	if (!netpoll)
  		return;
  
  	vlan->netpoll = NULL;
  	__netpoll_free(netpoll);
  }
  #endif /* CONFIG_NET_POLL_CONTROLLER */
  
  static int vlan_dev_get_iflink(const struct net_device *dev)
  {
  	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
  
  	return real_dev->ifindex;
  }
  
  static int vlan_dev_fill_forward_path(struct net_device_path_ctx *ctx,
  				      struct net_device_path *path)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(ctx->dev);
  
  	path->type = DEV_PATH_VLAN;
  	path->encap.id = vlan->vlan_id;
  	path->encap.proto = vlan->vlan_proto;
  	path->dev = ctx->dev;
  	ctx->dev = vlan->real_dev;
  	if (ctx->num_vlans >= ARRAY_SIZE(ctx->vlan))
  		return -ENOSPC;
  
  	ctx->vlan[ctx->num_vlans].id = vlan->vlan_id;
  	ctx->vlan[ctx->num_vlans].proto = vlan->vlan_proto;
  	ctx->num_vlans++;
  
  	return 0;
  }
  
  static const struct ethtool_ops vlan_ethtool_ops = {
  	.get_link_ksettings	= vlan_ethtool_get_link_ksettings,
  	.get_drvinfo	        = vlan_ethtool_get_drvinfo,
  	.get_link		= ethtool_op_get_link,
  	.get_ts_info		= vlan_ethtool_get_ts_info,
  };
  
  static const struct net_device_ops vlan_netdev_ops = {
  	.ndo_change_mtu		= vlan_dev_change_mtu,
  	.ndo_init		= vlan_dev_init,
  	.ndo_uninit		= vlan_dev_uninit,
  	.ndo_open		= vlan_dev_open,
  	.ndo_stop		= vlan_dev_stop,
  	.ndo_start_xmit =  vlan_dev_hard_start_xmit,
  	.ndo_validate_addr	= eth_validate_addr,
  	.ndo_set_mac_address	= vlan_dev_set_mac_address,
  	.ndo_set_rx_mode	= vlan_dev_set_rx_mode,
  	.ndo_change_rx_flags	= vlan_dev_change_rx_flags,
  	.ndo_eth_ioctl		= vlan_dev_ioctl,
  	.ndo_neigh_setup	= vlan_dev_neigh_setup,
  	.ndo_get_stats64	= vlan_dev_get_stats64,
  #if IS_ENABLED(CONFIG_FCOE)
  	.ndo_fcoe_ddp_setup	= vlan_dev_fcoe_ddp_setup,
  	.ndo_fcoe_ddp_done	= vlan_dev_fcoe_ddp_done,
  	.ndo_fcoe_enable	= vlan_dev_fcoe_enable,
  	.ndo_fcoe_disable	= vlan_dev_fcoe_disable,
  	.ndo_fcoe_ddp_target	= vlan_dev_fcoe_ddp_target,
  #endif
  #ifdef NETDEV_FCOE_WWNN
  	.ndo_fcoe_get_wwn	= vlan_dev_fcoe_get_wwn,
  #endif
  #ifdef CONFIG_NET_POLL_CONTROLLER
  	.ndo_poll_controller	= vlan_dev_poll_controller,
  	.ndo_netpoll_setup	= vlan_dev_netpoll_setup,
  	.ndo_netpoll_cleanup	= vlan_dev_netpoll_cleanup,
  #endif
  	.ndo_fix_features	= vlan_dev_fix_features,
  	.ndo_get_iflink		= vlan_dev_get_iflink,
  	.ndo_fill_forward_path	= vlan_dev_fill_forward_path,
  };
  
  static void vlan_dev_free(struct net_device *dev)
  {
  	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
  
  	free_percpu(vlan->vlan_pcpu_stats);
  	vlan->vlan_pcpu_stats = NULL;
  }
  
  void vlan_setup(struct net_device *dev)
  {
  	ether_setup(dev);
  
  	dev->priv_flags		|= IFF_802_1Q_VLAN | IFF_NO_QUEUE;
  	dev->priv_flags		|= IFF_UNICAST_FLT;
  	dev->priv_flags		&= ~IFF_TX_SKB_SHARING;
  	netif_keep_dst(dev);
  
  	dev->netdev_ops		= &vlan_netdev_ops;
  	dev->needs_free_netdev	= true;
  	dev->priv_destructor	= vlan_dev_free;
  	dev->ethtool_ops	= &vlan_ethtool_ops;
  
  	dev->min_mtu		= 0;
  	dev->max_mtu		= ETH_MAX_MTU;
  
  	eth_zero_addr(dev->broadcast);
  }
  