openvswitch: Rename GENEVE_TUN_OPTS() to TUN_METADATA_OPTS()

Also factors out Geneve validation code into a new separate function
validate_and_copy_geneve_opts().

A subsequent patch will introduce VXLAN options. Rename the existing
GENEVE_TUN_OPTS() to reflect its extended purpose of carrying generic
tunnel metadata options.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/openvswitch/flow.h b/net/openvswitch/flow.h
index a8b30f3..d3d0a40 100644
--- a/net/openvswitch/flow.h
+++ b/net/openvswitch/flow.h
@@ -53,7 +53,7 @@
 
 struct ovs_tunnel_info {
 	struct ovs_key_ipv4_tunnel tunnel;
-	const struct geneve_opt *options;
+	const void *options;
 	u8 options_len;
 };
 
@@ -61,10 +61,10 @@
  * maximum size. This allows us to get the benefits of variable length
  * matching for small options.
  */
-#define GENEVE_OPTS(flow_key, opt_len)	\
-	((struct geneve_opt *)((flow_key)->tun_opts + \
-			       FIELD_SIZEOF(struct sw_flow_key, tun_opts) - \
-			       opt_len))
+#define TUN_METADATA_OFFSET(opt_len) \
+	(FIELD_SIZEOF(struct sw_flow_key, tun_opts) - opt_len)
+#define TUN_METADATA_OPTS(flow_key, opt_len) \
+	((void *)((flow_key)->tun_opts + TUN_METADATA_OFFSET(opt_len)))
 
 static inline void __ovs_flow_tun_info_init(struct ovs_tunnel_info *tun_info,
 					    __be32 saddr, __be32 daddr,
@@ -73,7 +73,7 @@
 					    __be16 tp_dst,
 					    __be64 tun_id,
 					    __be16 tun_flags,
-					    const struct geneve_opt *opts,
+					    const void *opts,
 					    u8 opts_len)
 {
 	tun_info->tunnel.tun_id = tun_id;
@@ -105,7 +105,7 @@
 					  __be16 tp_dst,
 					  __be64 tun_id,
 					  __be16 tun_flags,
-					  const struct geneve_opt *opts,
+					  const void *opts,
 					  u8 opts_len)
 {
 	__ovs_flow_tun_info_init(tun_info, iph->saddr, iph->daddr,