[PATCH net-next 2/5] mptcp: split FASTCLOSE key from rcvr_key

[Matthieu Baerts (NGI0)]

From: Quanye Yang <quanyeyang@xxxxxxxxx>

MP_CAPABLE and MP_FASTCLOSE both stored their key in rcvr_key. Give
FASTCLOSE a dedicated fc_recv_key overlapped with rcvr_key in a union.

This helps shrink struct mptcp_options_received.

Signed-off-by: Quanye Yang <quanyeyang@xxxxxxxxx>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
---
 net/mptcp/options.c  | 6 +++---
 net/mptcp/protocol.h | 5 ++++-
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index ce0de02f5a3a..c2f4d7bd080c 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -374,10 +374,10 @@ static void mptcp_parse_option(const struct sk_buff *skb,
 			break;
 
 		ptr += 2;
-		mp_opt->rcvr_key = get_unaligned_be64(ptr);
+		mp_opt->fc_recv_key = get_unaligned_be64(ptr);
 		ptr += 8;
 		mp_opt->suboptions |= OPTION_MPTCP_FASTCLOSE;
-		pr_debug("MP_FASTCLOSE: recv_key=%llu\n", mp_opt->rcvr_key);
+		pr_debug("MP_FASTCLOSE: recv_key=%llu\n", mp_opt->fc_recv_key);
 		break;
 
 	case MPTCPOPT_RST:
@@ -1258,7 +1258,7 @@ bool mptcp_incoming_options(struct sock *sk, struct sk_buff *skb)
 
 	if (unlikely(mp_opt.suboptions != OPTION_MPTCP_DSS)) {
 		if ((mp_opt.suboptions & OPTION_MPTCP_FASTCLOSE) &&
-		    READ_ONCE(msk->local_key) == mp_opt.rcvr_key) {
+		    READ_ONCE(msk->local_key) == mp_opt.fc_recv_key) {
 			WRITE_ONCE(msk->rcv_fastclose, true);
 			mptcp_schedule_work((struct sock *)msk);
 			MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPFASTCLOSERX);
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index dd9957d334b6..6b9bffc5992b 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -146,7 +146,10 @@ static inline bool before64(__u64 seq1, __u64 seq2)
 
 struct mptcp_options_received {
 	u64	sndr_key;
-	u64	rcvr_key;
+	union {
+		u64	rcvr_key;
+		u64	fc_recv_key;
+	};
 	u64	data_ack;
 	u64	data_seq;
 	u32	subflow_seq;

-- 
2.55.0