diff --git a/include/net/mptcp.h b/include/net/mptcp.h
index b6cf07143a8a..3d57607982fa 100644
--- a/include/net/mptcp.h
+++ b/include/net/mptcp.h
@@ -78,6 +78,11 @@ static inline bool rsk_drop_req(const struct request_sock *req)
 	return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;
 }
 
+static inline struct mptcp_ext *mptcp_get_ext(struct sk_buff *skb)
+{
+	return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP);
+}
+
 void mptcp_space(const struct sock *ssk, int *space, int *full_space);
 bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
 		       unsigned int *size, struct mptcp_out_options *opts);
@@ -169,6 +174,11 @@ static inline bool rsk_drop_req(const struct request_sock *req)
 	return false;
 }
 
+static inline struct mptcp_ext *mptcp_get_ext(struct sk_buff *skb)
+{
+	return NULL;
+}
+
 static inline void mptcp_parse_option(const struct sk_buff *skb,
 				      const unsigned char *ptr, int opsize,
 				      struct tcp_options_received *opt_rx)
diff --git a/include/net/tcp.h b/include/net/tcp.h
index f3d42cb626fc..8115164e0df6 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -2377,4 +2377,9 @@ static inline u64 tcp_transmit_time(const struct sock *sk)
 	return 0;
 }
 
+static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field)
+{
+	return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) |
+		     ((nib & 0xF) << 8) | field);
+}
 #endif	/* _TCP_H */
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index d29c6a4749eb..66bd4d096753 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -139,12 +139,6 @@ struct mptcp_options_received {
 	u16	port;
 };
 
-static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field)
-{
-	return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) |
-		     ((nib & 0xF) << 8) | field);
-}
-
 struct mptcp_addr_info {
 	sa_family_t		family;
 	__be16			port;
@@ -568,11 +562,6 @@ void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk);
 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, u8 rm_id);
 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
 
-static inline struct mptcp_ext *mptcp_get_ext(struct sk_buff *skb)
-{
-	return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP);
-}
-
 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops);
 
 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk)