Merge branch 'inet_csums'

Tom Herbert says:

====================
net: Support checksum in UDP

This patch series adds support for using checksums in UDP tunnels. With
this it is possible that two or more checksums may be set within the
same packet and we would like to do that efficiently.

This series also creates some new helper functions to be used by various
tunnel protocol implementations.

v2: Fixed indentation in tcp_v6_send_check arguments.
v3: Move udp_set_csum and udp6_set_csum to be not inlined
    Also have this functions call with a nocheck boolean argument
    instead of passing a sock structure.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

7 files changed, 70 insertions, 4 deletions

diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index c26d0ec2ef3a..e5a589435e2b 100644
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -42,9 +42,11 @@ enum {
 	NETIF_F_TSO6_BIT,		/* ... TCPv6 segmentation */
 	NETIF_F_FSO_BIT,		/* ... FCoE segmentation */
 	NETIF_F_GSO_GRE_BIT,		/* ... GRE with TSO */
+	NETIF_F_GSO_GRE_CSUM_BIT,	/* ... GRE with csum with TSO */
 	NETIF_F_GSO_IPIP_BIT,		/* ... IPIP tunnel with TSO */
 	NETIF_F_GSO_SIT_BIT,		/* ... SIT tunnel with TSO */
 	NETIF_F_GSO_UDP_TUNNEL_BIT,	/* ... UDP TUNNEL with TSO */
+	NETIF_F_GSO_UDP_TUNNEL_CSUM_BIT,/* ... UDP TUNNEL with TSO & CSUM */
 	NETIF_F_GSO_MPLS_BIT,		/* ... MPLS segmentation */
 	/**/NETIF_F_GSO_LAST =		/* last bit, see GSO_MASK */
 		NETIF_F_GSO_MPLS_BIT,
@@ -111,6 +113,7 @@ enum {
 #define NETIF_F_RXFCS		__NETIF_F(RXFCS)
 #define NETIF_F_RXALL		__NETIF_F(RXALL)
 #define NETIF_F_GSO_GRE		__NETIF_F(GSO_GRE)
+#define NETIF_F_GSO_GRE_CSUM	__NETIF_F(GSO_GRE_CSUM)
 #define NETIF_F_GSO_IPIP	__NETIF_F(GSO_IPIP)
 #define NETIF_F_GSO_SIT		__NETIF_F(GSO_SIT)
 #define NETIF_F_GSO_UDP_TUNNEL	__NETIF_F(GSO_UDP_TUNNEL)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 7a9beeb1c458..c705808bef9c 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -345,6 +345,10 @@ enum {
 	SKB_GSO_UDP_TUNNEL = 1 << 9,
 
 	SKB_GSO_MPLS = 1 << 10,
+
+	SKB_GSO_UDP_TUNNEL_CSUM = 1 << 11,
+
+	SKB_GSO_GRE_CSUM = 1 << 12,
 };
 
 #if BITS_PER_LONG > 32
@@ -567,7 +571,8 @@ struct sk_buff {
 	 * headers if needed
 	 */
 	__u8			encapsulation:1;
-	/* 6/8 bit hole (depending on ndisc_nodetype presence) */
+	__u8			encap_hdr_csum:1;
+	/* 5/7 bit hole (depending on ndisc_nodetype presence) */
 	kmemcheck_bitfield_end(flags2);
 
 #if defined CONFIG_NET_DMA || defined CONFIG_NET_RX_BUSY_POLL
@@ -2988,6 +2993,7 @@ static inline struct sec_path *skb_sec_path(struct sk_buff *skb)
 struct skb_gso_cb {
 	int	mac_offset;
 	int	encap_level;
+	__u16	csum_start;
 };
 #define SKB_GSO_CB(skb) ((struct skb_gso_cb *)(skb)->cb)
 
@@ -3012,6 +3018,28 @@ static inline int gso_pskb_expand_head(struct sk_buff *skb, int extra)
 	return 0;
 }
 
+/* Compute the checksum for a gso segment. First compute the checksum value
+ * from the start of transport header to SKB_GSO_CB(skb)->csum_start, and
+ * then add in skb->csum (checksum from csum_start to end of packet).
+ * skb->csum and csum_start are then updated to reflect the checksum of the
+ * resultant packet starting from the transport header-- the resultant checksum
+ * is in the res argument (i.e. normally zero or ~ of checksum of a pseudo
+ * header.
+ */
+static inline __sum16 gso_make_checksum(struct sk_buff *skb, __wsum res)
+{
+	int plen = SKB_GSO_CB(skb)->csum_start - skb_headroom(skb) -
+	    skb_transport_offset(skb);
+	__u16 csum;
+
+	csum = csum_fold(csum_partial(skb_transport_header(skb),
+				      plen, skb->csum));
+	skb->csum = res;
+	SKB_GSO_CB(skb)->csum_start -= plen;
+
+	return csum;
+}
+
 static inline bool skb_is_gso(const struct sk_buff *skb)
 {
 	return skb_shinfo(skb)->gso_size;
diff --git a/include/net/gre.h b/include/net/gre.h
index 70046a0b0b89..b53182018743 100644
--- a/include/net/gre.h
+++ b/include/net/gre.h
@@ -37,9 +37,10 @@ void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
 		      int hdr_len);
 
 static inline struct sk_buff *gre_handle_offloads(struct sk_buff *skb,
-						  bool gre_csum)
+						  bool csum)
 {
-	return iptunnel_handle_offloads(skb, gre_csum, SKB_GSO_GRE);
+	return iptunnel_handle_offloads(skb, csum,
+					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
 }
 
 
diff --git a/include/net/ip6_checksum.h b/include/net/ip6_checksum.h
index 8ac5c21f8456..55236cb71174 100644
--- a/include/net/ip6_checksum.h
+++ b/include/net/ip6_checksum.h
@@ -82,5 +82,17 @@ static inline void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)
 }
 #endif
 
+static inline __sum16 udp_v6_check(int len,
+				   const struct in6_addr *saddr,
+				   const struct in6_addr *daddr,
+				   __wsum base)
+{
+	return csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, base);
+}
+
+void udp6_set_csum(bool nocheck, struct sk_buff *skb,
+		   const struct in6_addr *saddr,
+		   const struct in6_addr *daddr, int len);
+
 int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto);
 #endif
diff --git a/include/net/udp.h b/include/net/udp.h
index 5eb86874bcd6..2ecfc6e15609 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -147,6 +147,15 @@ static inline __wsum udp_csum(struct sk_buff *skb)
 	return csum;
 }
 
+static inline __sum16 udp_v4_check(int len, __be32 saddr,
+				   __be32 daddr, __wsum base)
+{
+	return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base);
+}
+
+void udp_set_csum(bool nocheck, struct sk_buff *skb,
+		  __be32 saddr, __be32 daddr, int len);
+
 /* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
 static inline void udp_lib_hash(struct sock *sk)
 {
diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index 7bb4084b1bd0..12196ce661d9 100644
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -24,9 +24,19 @@ struct vxlan_sock {
 	struct udp_offload udp_offloads;
 };
 
+#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_CSUM		0x40
+#define VXLAN_F_UDP_ZERO_CSUM6_TX	0x80
+#define VXLAN_F_UDP_ZERO_CSUM6_RX	0x100
+
 struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
 				  vxlan_rcv_t *rcv, void *data,
-				  bool no_share, bool ipv6);
+				  bool no_share, u32 flags);
 
 void vxlan_sock_release(struct vxlan_sock *vs);
 
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 622e7910b8cc..b38534895db5 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -319,6 +319,9 @@ enum {
 	IFLA_VXLAN_PORT,	/* destination port */
 	IFLA_VXLAN_GROUP6,
 	IFLA_VXLAN_LOCAL6,
+	IFLA_VXLAN_UDP_CSUM,
+	IFLA_VXLAN_UDP_ZERO_CSUM6_TX,
+	IFLA_VXLAN_UDP_ZERO_CSUM6_RX,
 	__IFLA_VXLAN_MAX
 };
 #define IFLA_VXLAN_MAX	(__IFLA_VXLAN_MAX - 1)