v4.19.13 snapshot.
diff --git a/include/net/vxlan.h b/include/net/vxlan.h
new file mode 100644
index 0000000..b99a02a
--- /dev/null
+++ b/include/net/vxlan.h
@@ -0,0 +1,374 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NET_VXLAN_H
+#define __NET_VXLAN_H 1
+
+#include <linux/if_vlan.h>
+#include <net/udp_tunnel.h>
+#include <net/dst_metadata.h>
+#include <net/udp_tunnel.h>
+
+/* VXLAN protocol (RFC 7348) header:
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |R|R|R|R|I|R|R|R|               Reserved                        |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |                VXLAN Network Identifier (VNI) |   Reserved    |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * I = VXLAN Network Identifier (VNI) present.
+ */
+struct vxlanhdr {
+	__be32 vx_flags;
+	__be32 vx_vni;
+};
+
+/* VXLAN header flags. */
+#define VXLAN_HF_VNI	cpu_to_be32(BIT(27))
+
+#define VXLAN_N_VID     (1u << 24)
+#define VXLAN_VID_MASK  (VXLAN_N_VID - 1)
+#define VXLAN_VNI_MASK	cpu_to_be32(VXLAN_VID_MASK << 8)
+#define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
+
+#define VNI_HASH_BITS	10
+#define VNI_HASH_SIZE	(1<<VNI_HASH_BITS)
+#define FDB_HASH_BITS	8
+#define FDB_HASH_SIZE	(1<<FDB_HASH_BITS)
+
+/* Remote checksum offload for VXLAN (VXLAN_F_REMCSUM_[RT]X):
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |R|R|R|R|I|R|R|R|R|R|C|              Reserved                   |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |           VXLAN Network Identifier (VNI)      |O| Csum start  |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * C = Remote checksum offload bit. When set indicates that the
+ *     remote checksum offload data is present.
+ *
+ * O = Offset bit. Indicates the checksum offset relative to
+ *     checksum start.
+ *
+ * Csum start = Checksum start divided by two.
+ *
+ * http://tools.ietf.org/html/draft-herbert-vxlan-rco
+ */
+
+/* VXLAN-RCO header flags. */
+#define VXLAN_HF_RCO	cpu_to_be32(BIT(21))
+
+/* Remote checksum offload header option */
+#define VXLAN_RCO_MASK	cpu_to_be32(0x7f)  /* Last byte of vni field */
+#define VXLAN_RCO_UDP	cpu_to_be32(0x80)  /* Indicate UDP RCO (TCP when not set *) */
+#define VXLAN_RCO_SHIFT	1		   /* Left shift of start */
+#define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1)
+#define VXLAN_MAX_REMCSUM_START (0x7f << VXLAN_RCO_SHIFT)
+
+/*
+ * VXLAN Group Based Policy Extension (VXLAN_F_GBP):
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |G|R|R|R|I|R|R|R|R|D|R|R|A|R|R|R|        Group Policy ID        |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |                VXLAN Network Identifier (VNI) |   Reserved    |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * G = Group Policy ID present.
+ *
+ * D = Don't Learn bit. When set, this bit indicates that the egress
+ *     VTEP MUST NOT learn the source address of the encapsulated frame.
+ *
+ * A = Indicates that the group policy has already been applied to
+ *     this packet. Policies MUST NOT be applied by devices when the
+ *     A bit is set.
+ *
+ * https://tools.ietf.org/html/draft-smith-vxlan-group-policy
+ */
+struct vxlanhdr_gbp {
+	u8	vx_flags;
+#ifdef __LITTLE_ENDIAN_BITFIELD
+	u8	reserved_flags1:3,
+		policy_applied:1,
+		reserved_flags2:2,
+		dont_learn:1,
+		reserved_flags3:1;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+	u8	reserved_flags1:1,
+		dont_learn:1,
+		reserved_flags2:2,
+		policy_applied:1,
+		reserved_flags3:3;
+#else
+#error	"Please fix <asm/byteorder.h>"
+#endif
+	__be16	policy_id;
+	__be32	vx_vni;
+};
+
+/* VXLAN-GBP header flags. */
+#define VXLAN_HF_GBP	cpu_to_be32(BIT(31))
+
+#define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | cpu_to_be32(0xFFFFFF))
+
+/* skb->mark mapping
+ *
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R|        Group Policy ID        |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+#define VXLAN_GBP_DONT_LEARN		(BIT(6) << 16)
+#define VXLAN_GBP_POLICY_APPLIED	(BIT(3) << 16)
+#define VXLAN_GBP_ID_MASK		(0xFFFF)
+
+/*
+ * VXLAN Generic Protocol Extension (VXLAN_F_GPE):
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |R|R|Ver|I|P|R|O|       Reserved                |Next Protocol  |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |                VXLAN Network Identifier (VNI) |   Reserved    |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * Ver = Version. Indicates VXLAN GPE protocol version.
+ *
+ * P = Next Protocol Bit. The P bit is set to indicate that the
+ *     Next Protocol field is present.
+ *
+ * O = OAM Flag Bit. The O bit is set to indicate that the packet
+ *     is an OAM packet.
+ *
+ * Next Protocol = This 8 bit field indicates the protocol header
+ * immediately following the VXLAN GPE header.
+ *
+ * https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-01
+ */
+
+struct vxlanhdr_gpe {
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+	u8	oam_flag:1,
+		reserved_flags1:1,
+		np_applied:1,
+		instance_applied:1,
+		version:2,
+		reserved_flags2:2;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+	u8	reserved_flags2:2,
+		version:2,
+		instance_applied:1,
+		np_applied:1,
+		reserved_flags1:1,
+		oam_flag:1;
+#endif
+	u8	reserved_flags3;
+	u8	reserved_flags4;
+	u8	next_protocol;
+	__be32	vx_vni;
+};
+
+/* VXLAN-GPE header flags. */
+#define VXLAN_HF_VER	cpu_to_be32(BIT(29) | BIT(28))
+#define VXLAN_HF_NP	cpu_to_be32(BIT(26))
+#define VXLAN_HF_OAM	cpu_to_be32(BIT(24))
+
+#define VXLAN_GPE_USED_BITS (VXLAN_HF_VER | VXLAN_HF_NP | VXLAN_HF_OAM | \
+			     cpu_to_be32(0xff))
+
+struct vxlan_metadata {
+	u32		gbp;
+};
+
+/* per UDP socket information */
+struct vxlan_sock {
+	struct hlist_node hlist;
+	struct socket	 *sock;
+	struct hlist_head vni_list[VNI_HASH_SIZE];
+	refcount_t	  refcnt;
+	u32		  flags;
+};
+
+union vxlan_addr {
+	struct sockaddr_in sin;
+	struct sockaddr_in6 sin6;
+	struct sockaddr sa;
+};
+
+struct vxlan_rdst {
+	union vxlan_addr	 remote_ip;
+	__be16			 remote_port;
+	__be32			 remote_vni;
+	u32			 remote_ifindex;
+	struct list_head	 list;
+	struct rcu_head		 rcu;
+	struct dst_cache	 dst_cache;
+};
+
+struct vxlan_config {
+	union vxlan_addr	remote_ip;
+	union vxlan_addr	saddr;
+	__be32			vni;
+	int			remote_ifindex;
+	int			mtu;
+	__be16			dst_port;
+	u16			port_min;
+	u16			port_max;
+	u8			tos;
+	u8			ttl;
+	__be32			label;
+	u32			flags;
+	unsigned long		age_interval;
+	unsigned int		addrmax;
+	bool			no_share;
+};
+
+struct vxlan_dev_node {
+	struct hlist_node hlist;
+	struct vxlan_dev *vxlan;
+};
+
+/* Pseudo network device */
+struct vxlan_dev {
+	struct vxlan_dev_node hlist4;	/* vni hash table for IPv4 socket */
+#if IS_ENABLED(CONFIG_IPV6)
+	struct vxlan_dev_node hlist6;	/* vni hash table for IPv6 socket */
+#endif
+	struct list_head  next;		/* vxlan's per namespace list */
+	struct vxlan_sock __rcu *vn4_sock;	/* listening socket for IPv4 */
+#if IS_ENABLED(CONFIG_IPV6)
+	struct vxlan_sock __rcu *vn6_sock;	/* listening socket for IPv6 */
+#endif
+	struct net_device *dev;
+	struct net	  *net;		/* netns for packet i/o */
+	struct vxlan_rdst default_dst;	/* default destination */
+
+	struct timer_list age_timer;
+	spinlock_t	  hash_lock;
+	unsigned int	  addrcnt;
+	struct gro_cells  gro_cells;
+
+	struct vxlan_config	cfg;
+
+	struct hlist_head fdb_head[FDB_HASH_SIZE];
+};
+
+#define VXLAN_F_LEARN			0x01
+#define VXLAN_F_PROXY			0x02
+#define VXLAN_F_RSC			0x04
+#define VXLAN_F_L2MISS			0x08
+#define VXLAN_F_L3MISS			0x10
+#define VXLAN_F_IPV6			0x20
+#define VXLAN_F_UDP_ZERO_CSUM_TX	0x40
+#define VXLAN_F_UDP_ZERO_CSUM6_TX	0x80
+#define VXLAN_F_UDP_ZERO_CSUM6_RX	0x100
+#define VXLAN_F_REMCSUM_TX		0x200
+#define VXLAN_F_REMCSUM_RX		0x400
+#define VXLAN_F_GBP			0x800
+#define VXLAN_F_REMCSUM_NOPARTIAL	0x1000
+#define VXLAN_F_COLLECT_METADATA	0x2000
+#define VXLAN_F_GPE			0x4000
+#define VXLAN_F_IPV6_LINKLOCAL		0x8000
+#define VXLAN_F_TTL_INHERIT		0x10000
+
+/* Flags that are used in the receive path. These flags must match in
+ * order for a socket to be shareable
+ */
+#define VXLAN_F_RCV_FLAGS		(VXLAN_F_GBP |			\
+					 VXLAN_F_GPE |			\
+					 VXLAN_F_UDP_ZERO_CSUM6_RX |	\
+					 VXLAN_F_REMCSUM_RX |		\
+					 VXLAN_F_REMCSUM_NOPARTIAL |	\
+					 VXLAN_F_COLLECT_METADATA)
+
+/* Flags that can be set together with VXLAN_F_GPE. */
+#define VXLAN_F_ALLOWED_GPE		(VXLAN_F_GPE |			\
+					 VXLAN_F_IPV6 |			\
+					 VXLAN_F_IPV6_LINKLOCAL |	\
+					 VXLAN_F_UDP_ZERO_CSUM_TX |	\
+					 VXLAN_F_UDP_ZERO_CSUM6_TX |	\
+					 VXLAN_F_UDP_ZERO_CSUM6_RX |	\
+					 VXLAN_F_COLLECT_METADATA)
+
+struct net_device *vxlan_dev_create(struct net *net, const char *name,
+				    u8 name_assign_type, struct vxlan_config *conf);
+
+static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
+						     netdev_features_t features)
+{
+	u8 l4_hdr = 0;
+
+	if (!skb->encapsulation)
+		return features;
+
+	switch (vlan_get_protocol(skb)) {
+	case htons(ETH_P_IP):
+		l4_hdr = ip_hdr(skb)->protocol;
+		break;
+	case htons(ETH_P_IPV6):
+		l4_hdr = ipv6_hdr(skb)->nexthdr;
+		break;
+	default:
+		return features;
+	}
+
+	if ((l4_hdr == IPPROTO_UDP) &&
+	    (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
+	     skb->inner_protocol != htons(ETH_P_TEB) ||
+	     (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
+	      sizeof(struct udphdr) + sizeof(struct vxlanhdr)) ||
+	     (skb->ip_summed != CHECKSUM_NONE &&
+	      !can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto))))
+		return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
+
+	return features;
+}
+
+/* IP header + UDP + VXLAN + Ethernet header */
+#define VXLAN_HEADROOM (20 + 8 + 8 + 14)
+/* IPv6 header + UDP + VXLAN + Ethernet header */
+#define VXLAN6_HEADROOM (40 + 8 + 8 + 14)
+
+static inline struct vxlanhdr *vxlan_hdr(struct sk_buff *skb)
+{
+	return (struct vxlanhdr *)(udp_hdr(skb) + 1);
+}
+
+static inline __be32 vxlan_vni(__be32 vni_field)
+{
+#if defined(__BIG_ENDIAN)
+	return (__force __be32)((__force u32)vni_field >> 8);
+#else
+	return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8);
+#endif
+}
+
+static inline __be32 vxlan_vni_field(__be32 vni)
+{
+#if defined(__BIG_ENDIAN)
+	return (__force __be32)((__force u32)vni << 8);
+#else
+	return (__force __be32)((__force u32)vni >> 8);
+#endif
+}
+
+static inline size_t vxlan_rco_start(__be32 vni_field)
+{
+	return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT;
+}
+
+static inline size_t vxlan_rco_offset(__be32 vni_field)
+{
+	return (vni_field & VXLAN_RCO_UDP) ?
+		offsetof(struct udphdr, check) :
+		offsetof(struct tcphdr, check);
+}
+
+static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset)
+{
+	__be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT);
+
+	if (offset == offsetof(struct udphdr, check))
+		vni_field |= VXLAN_RCO_UDP;
+	return vni_field;
+}
+
+static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs)
+{
+	return vs->sock->sk->sk_family;
+}
+
+#endif