v4.19.13 snapshot.
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
new file mode 100644
index 0000000..83ea4df
--- /dev/null
+++ b/include/linux/if_vlan.h
@@ -0,0 +1,733 @@
+/*
+ * VLAN		An implementation of 802.1Q VLAN tagging.
+ *
+ * Authors:	Ben Greear <greearb@candelatech.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.
+ *
+ */
+#ifndef _LINUX_IF_VLAN_H_
+#define _LINUX_IF_VLAN_H_
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/bug.h>
+#include <uapi/linux/if_vlan.h>
+
+#define VLAN_HLEN	4		/* The additional bytes required by VLAN
+					 * (in addition to the Ethernet header)
+					 */
+#define VLAN_ETH_HLEN	18		/* Total octets in header.	 */
+#define VLAN_ETH_ZLEN	64		/* Min. octets in frame sans FCS */
+
+/*
+ * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
+ */
+#define VLAN_ETH_DATA_LEN	1500	/* Max. octets in payload	 */
+#define VLAN_ETH_FRAME_LEN	1518	/* Max. octets in frame sans FCS */
+
+/*
+ * 	struct vlan_hdr - vlan header
+ * 	@h_vlan_TCI: priority and VLAN ID
+ *	@h_vlan_encapsulated_proto: packet type ID or len
+ */
+struct vlan_hdr {
+	__be16	h_vlan_TCI;
+	__be16	h_vlan_encapsulated_proto;
+};
+
+/**
+ *	struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr)
+ *	@h_dest: destination ethernet address
+ *	@h_source: source ethernet address
+ *	@h_vlan_proto: ethernet protocol
+ *	@h_vlan_TCI: priority and VLAN ID
+ *	@h_vlan_encapsulated_proto: packet type ID or len
+ */
+struct vlan_ethhdr {
+	unsigned char	h_dest[ETH_ALEN];
+	unsigned char	h_source[ETH_ALEN];
+	__be16		h_vlan_proto;
+	__be16		h_vlan_TCI;
+	__be16		h_vlan_encapsulated_proto;
+};
+
+#include <linux/skbuff.h>
+
+static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
+{
+	return (struct vlan_ethhdr *)skb_mac_header(skb);
+}
+
+#define VLAN_PRIO_MASK		0xe000 /* Priority Code Point */
+#define VLAN_PRIO_SHIFT		13
+#define VLAN_CFI_MASK		0x1000 /* Canonical Format Indicator */
+#define VLAN_TAG_PRESENT	VLAN_CFI_MASK
+#define VLAN_VID_MASK		0x0fff /* VLAN Identifier */
+#define VLAN_N_VID		4096
+
+/* found in socket.c */
+extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
+
+static inline bool is_vlan_dev(const struct net_device *dev)
+{
+        return dev->priv_flags & IFF_802_1Q_VLAN;
+}
+
+#define skb_vlan_tag_present(__skb)	((__skb)->vlan_tci & VLAN_TAG_PRESENT)
+#define skb_vlan_tag_get(__skb)		((__skb)->vlan_tci & ~VLAN_TAG_PRESENT)
+#define skb_vlan_tag_get_id(__skb)	((__skb)->vlan_tci & VLAN_VID_MASK)
+#define skb_vlan_tag_get_prio(__skb)	((__skb)->vlan_tci & VLAN_PRIO_MASK)
+
+static inline int vlan_get_rx_ctag_filter_info(struct net_device *dev)
+{
+	ASSERT_RTNL();
+	return notifier_to_errno(call_netdevice_notifiers(NETDEV_CVLAN_FILTER_PUSH_INFO, dev));
+}
+
+static inline void vlan_drop_rx_ctag_filter_info(struct net_device *dev)
+{
+	ASSERT_RTNL();
+	call_netdevice_notifiers(NETDEV_CVLAN_FILTER_DROP_INFO, dev);
+}
+
+static inline int vlan_get_rx_stag_filter_info(struct net_device *dev)
+{
+	ASSERT_RTNL();
+	return notifier_to_errno(call_netdevice_notifiers(NETDEV_SVLAN_FILTER_PUSH_INFO, dev));
+}
+
+static inline void vlan_drop_rx_stag_filter_info(struct net_device *dev)
+{
+	ASSERT_RTNL();
+	call_netdevice_notifiers(NETDEV_SVLAN_FILTER_DROP_INFO, dev);
+}
+
+/**
+ *	struct vlan_pcpu_stats - VLAN percpu rx/tx stats
+ *	@rx_packets: number of received packets
+ *	@rx_bytes: number of received bytes
+ *	@rx_multicast: number of received multicast packets
+ *	@tx_packets: number of transmitted packets
+ *	@tx_bytes: number of transmitted bytes
+ *	@syncp: synchronization point for 64bit counters
+ *	@rx_errors: number of rx errors
+ *	@tx_dropped: number of tx drops
+ */
+struct vlan_pcpu_stats {
+	u64			rx_packets;
+	u64			rx_bytes;
+	u64			rx_multicast;
+	u64			tx_packets;
+	u64			tx_bytes;
+	struct u64_stats_sync	syncp;
+	u32			rx_errors;
+	u32			tx_dropped;
+};
+
+#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
+
+extern struct net_device *__vlan_find_dev_deep_rcu(struct net_device *real_dev,
+					       __be16 vlan_proto, u16 vlan_id);
+extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
+extern u16 vlan_dev_vlan_id(const struct net_device *dev);
+extern __be16 vlan_dev_vlan_proto(const struct net_device *dev);
+
+/**
+ *	struct vlan_priority_tci_mapping - vlan egress priority mappings
+ *	@priority: skb priority
+ *	@vlan_qos: vlan priority: (skb->priority << 13) & 0xE000
+ *	@next: pointer to next struct
+ */
+struct vlan_priority_tci_mapping {
+	u32					priority;
+	u16					vlan_qos;
+	struct vlan_priority_tci_mapping	*next;
+};
+
+struct proc_dir_entry;
+struct netpoll;
+
+/**
+ *	struct vlan_dev_priv - VLAN private device data
+ *	@nr_ingress_mappings: number of ingress priority mappings
+ *	@ingress_priority_map: ingress priority mappings
+ *	@nr_egress_mappings: number of egress priority mappings
+ *	@egress_priority_map: hash of egress priority mappings
+ *	@vlan_proto: VLAN encapsulation protocol
+ *	@vlan_id: VLAN identifier
+ *	@flags: device flags
+ *	@real_dev: underlying netdevice
+ *	@real_dev_addr: address of underlying netdevice
+ *	@dent: proc dir entry
+ *	@vlan_pcpu_stats: ptr to percpu rx stats
+ */
+struct vlan_dev_priv {
+	unsigned int				nr_ingress_mappings;
+	u32					ingress_priority_map[8];
+	unsigned int				nr_egress_mappings;
+	struct vlan_priority_tci_mapping	*egress_priority_map[16];
+
+	__be16					vlan_proto;
+	u16					vlan_id;
+	u16					flags;
+
+	struct net_device			*real_dev;
+	unsigned char				real_dev_addr[ETH_ALEN];
+
+	struct proc_dir_entry			*dent;
+	struct vlan_pcpu_stats __percpu		*vlan_pcpu_stats;
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	struct netpoll				*netpoll;
+#endif
+	unsigned int				nest_level;
+};
+
+static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
+{
+	return netdev_priv(dev);
+}
+
+static inline u16
+vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio)
+{
+	struct vlan_priority_tci_mapping *mp;
+
+	smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */
+
+	mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)];
+	while (mp) {
+		if (mp->priority == skprio) {
+			return mp->vlan_qos; /* This should already be shifted
+					      * to mask correctly with the
+					      * VLAN's TCI */
+		}
+		mp = mp->next;
+	}
+	return 0;
+}
+
+extern bool vlan_do_receive(struct sk_buff **skb);
+
+extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid);
+extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid);
+
+extern int vlan_vids_add_by_dev(struct net_device *dev,
+				const struct net_device *by_dev);
+extern void vlan_vids_del_by_dev(struct net_device *dev,
+				 const struct net_device *by_dev);
+
+extern bool vlan_uses_dev(const struct net_device *dev);
+
+static inline int vlan_get_encap_level(struct net_device *dev)
+{
+	BUG_ON(!is_vlan_dev(dev));
+	return vlan_dev_priv(dev)->nest_level;
+}
+#else
+static inline struct net_device *
+__vlan_find_dev_deep_rcu(struct net_device *real_dev,
+		     __be16 vlan_proto, u16 vlan_id)
+{
+	return NULL;
+}
+
+static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
+{
+	BUG();
+	return NULL;
+}
+
+static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
+{
+	BUG();
+	return 0;
+}
+
+static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
+{
+	BUG();
+	return 0;
+}
+
+static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev,
+					       u32 skprio)
+{
+	return 0;
+}
+
+static inline bool vlan_do_receive(struct sk_buff **skb)
+{
+	return false;
+}
+
+static inline int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
+{
+	return 0;
+}
+
+static inline void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
+{
+}
+
+static inline int vlan_vids_add_by_dev(struct net_device *dev,
+				       const struct net_device *by_dev)
+{
+	return 0;
+}
+
+static inline void vlan_vids_del_by_dev(struct net_device *dev,
+					const struct net_device *by_dev)
+{
+}
+
+static inline bool vlan_uses_dev(const struct net_device *dev)
+{
+	return false;
+}
+static inline int vlan_get_encap_level(struct net_device *dev)
+{
+	BUG();
+	return 0;
+}
+#endif
+
+/**
+ * eth_type_vlan - check for valid vlan ether type.
+ * @ethertype: ether type to check
+ *
+ * Returns true if the ether type is a vlan ether type.
+ */
+static inline bool eth_type_vlan(__be16 ethertype)
+{
+	switch (ethertype) {
+	case htons(ETH_P_8021Q):
+	case htons(ETH_P_8021AD):
+		return true;
+	default:
+		return false;
+	}
+}
+
+static inline bool vlan_hw_offload_capable(netdev_features_t features,
+					   __be16 proto)
+{
+	if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX)
+		return true;
+	if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX)
+		return true;
+	return false;
+}
+
+/**
+ * __vlan_insert_inner_tag - inner VLAN tag inserting
+ * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
+ * @vlan_tci: VLAN TCI to insert
+ * @mac_len: MAC header length including outer vlan headers
+ *
+ * Inserts the VLAN tag into @skb as part of the payload at offset mac_len
+ * Returns error if skb_cow_head fails.
+ *
+ * Does not change skb->protocol so this function can be used during receive.
+ */
+static inline int __vlan_insert_inner_tag(struct sk_buff *skb,
+					  __be16 vlan_proto, u16 vlan_tci,
+					  unsigned int mac_len)
+{
+	struct vlan_ethhdr *veth;
+
+	if (skb_cow_head(skb, VLAN_HLEN) < 0)
+		return -ENOMEM;
+
+	skb_push(skb, VLAN_HLEN);
+
+	/* Move the mac header sans proto to the beginning of the new header. */
+	if (likely(mac_len > ETH_TLEN))
+		memmove(skb->data, skb->data + VLAN_HLEN, mac_len - ETH_TLEN);
+	skb->mac_header -= VLAN_HLEN;
+
+	veth = (struct vlan_ethhdr *)(skb->data + mac_len - ETH_HLEN);
+
+	/* first, the ethernet type */
+	if (likely(mac_len >= ETH_TLEN)) {
+		/* h_vlan_encapsulated_proto should already be populated, and
+		 * skb->data has space for h_vlan_proto
+		 */
+		veth->h_vlan_proto = vlan_proto;
+	} else {
+		/* h_vlan_encapsulated_proto should not be populated, and
+		 * skb->data has no space for h_vlan_proto
+		 */
+		veth->h_vlan_encapsulated_proto = skb->protocol;
+	}
+
+	/* now, the TCI */
+	veth->h_vlan_TCI = htons(vlan_tci);
+
+	return 0;
+}
+
+/**
+ * __vlan_insert_tag - regular VLAN tag inserting
+ * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
+ * @vlan_tci: VLAN TCI to insert
+ *
+ * Inserts the VLAN tag into @skb as part of the payload
+ * Returns error if skb_cow_head fails.
+ *
+ * Does not change skb->protocol so this function can be used during receive.
+ */
+static inline int __vlan_insert_tag(struct sk_buff *skb,
+				    __be16 vlan_proto, u16 vlan_tci)
+{
+	return __vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, ETH_HLEN);
+}
+
+/**
+ * vlan_insert_inner_tag - inner VLAN tag inserting
+ * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
+ * @vlan_tci: VLAN TCI to insert
+ * @mac_len: MAC header length including outer vlan headers
+ *
+ * Inserts the VLAN tag into @skb as part of the payload at offset mac_len
+ * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
+ *
+ * Following the skb_unshare() example, in case of error, the calling function
+ * doesn't have to worry about freeing the original skb.
+ *
+ * Does not change skb->protocol so this function can be used during receive.
+ */
+static inline struct sk_buff *vlan_insert_inner_tag(struct sk_buff *skb,
+						    __be16 vlan_proto,
+						    u16 vlan_tci,
+						    unsigned int mac_len)
+{
+	int err;
+
+	err = __vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, mac_len);
+	if (err) {
+		dev_kfree_skb_any(skb);
+		return NULL;
+	}
+	return skb;
+}
+
+/**
+ * vlan_insert_tag - regular VLAN tag inserting
+ * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
+ * @vlan_tci: VLAN TCI to insert
+ *
+ * Inserts the VLAN tag into @skb as part of the payload
+ * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
+ *
+ * Following the skb_unshare() example, in case of error, the calling function
+ * doesn't have to worry about freeing the original skb.
+ *
+ * Does not change skb->protocol so this function can be used during receive.
+ */
+static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
+					      __be16 vlan_proto, u16 vlan_tci)
+{
+	return vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, ETH_HLEN);
+}
+
+/**
+ * vlan_insert_tag_set_proto - regular VLAN tag inserting
+ * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
+ * @vlan_tci: VLAN TCI to insert
+ *
+ * Inserts the VLAN tag into @skb as part of the payload
+ * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
+ *
+ * Following the skb_unshare() example, in case of error, the calling function
+ * doesn't have to worry about freeing the original skb.
+ */
+static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
+							__be16 vlan_proto,
+							u16 vlan_tci)
+{
+	skb = vlan_insert_tag(skb, vlan_proto, vlan_tci);
+	if (skb)
+		skb->protocol = vlan_proto;
+	return skb;
+}
+
+/*
+ * __vlan_hwaccel_push_inside - pushes vlan tag to the payload
+ * @skb: skbuff to tag
+ *
+ * Pushes the VLAN tag from @skb->vlan_tci inside to the payload.
+ *
+ * Following the skb_unshare() example, in case of error, the calling function
+ * doesn't have to worry about freeing the original skb.
+ */
+static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb)
+{
+	skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
+					skb_vlan_tag_get(skb));
+	if (likely(skb))
+		skb->vlan_tci = 0;
+	return skb;
+}
+
+/**
+ * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
+ * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
+ * @vlan_tci: VLAN TCI to insert
+ *
+ * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
+ */
+static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb,
+					  __be16 vlan_proto, u16 vlan_tci)
+{
+	skb->vlan_proto = vlan_proto;
+	skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
+}
+
+/**
+ * __vlan_get_tag - get the VLAN ID that is part of the payload
+ * @skb: skbuff to query
+ * @vlan_tci: buffer to store value
+ *
+ * Returns error if the skb is not of VLAN type
+ */
+static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
+{
+	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
+
+	if (!eth_type_vlan(veth->h_vlan_proto))
+		return -EINVAL;
+
+	*vlan_tci = ntohs(veth->h_vlan_TCI);
+	return 0;
+}
+
+/**
+ * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
+ * @skb: skbuff to query
+ * @vlan_tci: buffer to store value
+ *
+ * Returns error if @skb->vlan_tci is not set correctly
+ */
+static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
+					 u16 *vlan_tci)
+{
+	if (skb_vlan_tag_present(skb)) {
+		*vlan_tci = skb_vlan_tag_get(skb);
+		return 0;
+	} else {
+		*vlan_tci = 0;
+		return -EINVAL;
+	}
+}
+
+#define HAVE_VLAN_GET_TAG
+
+/**
+ * vlan_get_tag - get the VLAN ID from the skb
+ * @skb: skbuff to query
+ * @vlan_tci: buffer to store value
+ *
+ * Returns error if the skb is not VLAN tagged
+ */
+static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
+{
+	if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) {
+		return __vlan_hwaccel_get_tag(skb, vlan_tci);
+	} else {
+		return __vlan_get_tag(skb, vlan_tci);
+	}
+}
+
+/**
+ * vlan_get_protocol - get protocol EtherType.
+ * @skb: skbuff to query
+ * @type: first vlan protocol
+ * @depth: buffer to store length of eth and vlan tags in bytes
+ *
+ * Returns the EtherType of the packet, regardless of whether it is
+ * vlan encapsulated (normal or hardware accelerated) or not.
+ */
+static inline __be16 __vlan_get_protocol(struct sk_buff *skb, __be16 type,
+					 int *depth)
+{
+	unsigned int vlan_depth = skb->mac_len;
+
+	/* if type is 802.1Q/AD then the header should already be
+	 * present at mac_len - VLAN_HLEN (if mac_len > 0), or at
+	 * ETH_HLEN otherwise
+	 */
+	if (eth_type_vlan(type)) {
+		if (vlan_depth) {
+			if (WARN_ON(vlan_depth < VLAN_HLEN))
+				return 0;
+			vlan_depth -= VLAN_HLEN;
+		} else {
+			vlan_depth = ETH_HLEN;
+		}
+		do {
+			struct vlan_hdr *vh;
+
+			if (unlikely(!pskb_may_pull(skb,
+						    vlan_depth + VLAN_HLEN)))
+				return 0;
+
+			vh = (struct vlan_hdr *)(skb->data + vlan_depth);
+			type = vh->h_vlan_encapsulated_proto;
+			vlan_depth += VLAN_HLEN;
+		} while (eth_type_vlan(type));
+	}
+
+	if (depth)
+		*depth = vlan_depth;
+
+	return type;
+}
+
+/**
+ * vlan_get_protocol - get protocol EtherType.
+ * @skb: skbuff to query
+ *
+ * Returns the EtherType of the packet, regardless of whether it is
+ * vlan encapsulated (normal or hardware accelerated) or not.
+ */
+static inline __be16 vlan_get_protocol(struct sk_buff *skb)
+{
+	return __vlan_get_protocol(skb, skb->protocol, NULL);
+}
+
+static inline void vlan_set_encap_proto(struct sk_buff *skb,
+					struct vlan_hdr *vhdr)
+{
+	__be16 proto;
+	unsigned short *rawp;
+
+	/*
+	 * Was a VLAN packet, grab the encapsulated protocol, which the layer
+	 * three protocols care about.
+	 */
+
+	proto = vhdr->h_vlan_encapsulated_proto;
+	if (eth_proto_is_802_3(proto)) {
+		skb->protocol = proto;
+		return;
+	}
+
+	rawp = (unsigned short *)(vhdr + 1);
+	if (*rawp == 0xFFFF)
+		/*
+		 * This is a magic hack to spot IPX packets. Older Novell
+		 * breaks the protocol design and runs IPX over 802.3 without
+		 * an 802.2 LLC layer. We look for FFFF which isn't a used
+		 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
+		 * but does for the rest.
+		 */
+		skb->protocol = htons(ETH_P_802_3);
+	else
+		/*
+		 * Real 802.2 LLC
+		 */
+		skb->protocol = htons(ETH_P_802_2);
+}
+
+/**
+ * skb_vlan_tagged - check if skb is vlan tagged.
+ * @skb: skbuff to query
+ *
+ * Returns true if the skb is tagged, regardless of whether it is hardware
+ * accelerated or not.
+ */
+static inline bool skb_vlan_tagged(const struct sk_buff *skb)
+{
+	if (!skb_vlan_tag_present(skb) &&
+	    likely(!eth_type_vlan(skb->protocol)))
+		return false;
+
+	return true;
+}
+
+/**
+ * skb_vlan_tagged_multi - check if skb is vlan tagged with multiple headers.
+ * @skb: skbuff to query
+ *
+ * Returns true if the skb is tagged with multiple vlan headers, regardless
+ * of whether it is hardware accelerated or not.
+ */
+static inline bool skb_vlan_tagged_multi(struct sk_buff *skb)
+{
+	__be16 protocol = skb->protocol;
+
+	if (!skb_vlan_tag_present(skb)) {
+		struct vlan_ethhdr *veh;
+
+		if (likely(!eth_type_vlan(protocol)))
+			return false;
+
+		if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
+			return false;
+
+		veh = (struct vlan_ethhdr *)skb->data;
+		protocol = veh->h_vlan_encapsulated_proto;
+	}
+
+	if (!eth_type_vlan(protocol))
+		return false;
+
+	return true;
+}
+
+/**
+ * vlan_features_check - drop unsafe features for skb with multiple tags.
+ * @skb: skbuff to query
+ * @features: features to be checked
+ *
+ * Returns features without unsafe ones if the skb has multiple tags.
+ */
+static inline netdev_features_t vlan_features_check(struct sk_buff *skb,
+						    netdev_features_t features)
+{
+	if (skb_vlan_tagged_multi(skb)) {
+		/* In the case of multi-tagged packets, use a direct mask
+		 * instead of using netdev_interesect_features(), to make
+		 * sure that only devices supporting NETIF_F_HW_CSUM will
+		 * have checksum offloading support.
+		 */
+		features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
+			    NETIF_F_FRAGLIST | NETIF_F_HW_VLAN_CTAG_TX |
+			    NETIF_F_HW_VLAN_STAG_TX;
+	}
+
+	return features;
+}
+
+/**
+ * compare_vlan_header - Compare two vlan headers
+ * @h1: Pointer to vlan header
+ * @h2: Pointer to vlan header
+ *
+ * Compare two vlan headers, returns 0 if equal.
+ *
+ * Please note that alignment of h1 & h2 are only guaranteed to be 16 bits.
+ */
+static inline unsigned long compare_vlan_header(const struct vlan_hdr *h1,
+						const struct vlan_hdr *h2)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
+	return *(u32 *)h1 ^ *(u32 *)h2;
+#else
+	return ((__force u32)h1->h_vlan_TCI ^ (__force u32)h2->h_vlan_TCI) |
+	       ((__force u32)h1->h_vlan_encapsulated_proto ^
+		(__force u32)h2->h_vlan_encapsulated_proto);
+#endif
+}
+#endif /* !(_LINUX_IF_VLAN_H_) */