Commit 0530020a authored by Geliang Tang's avatar Geliang Tang Committed by David S. Miller
Browse files

mptcp: track and update contiguous data status 



This patch adds a new member allow_infinite_fallback in mptcp_sock,
which is initialized to 'true' when the connection begins and is set
to 'false' on any retransmit or successful MP_JOIN. Only do infinite
mapping fallback if there is a single subflow AND there have been no
retransmissions AND there have never been any MP_JOINs.

Suggested-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarGeliang Tang <geliang.tang@suse.com>
Signed-off-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0348c690

net/mptcp/protocol.c

+3 −0
Original line number Diff line number Diff line
@@ -2465,6 +2465,7 @@ static void __mptcp_retrans(struct sock *sk) 
		dfrag->already_sent = max(dfrag->already_sent, info.sent);

		tcp_push(ssk, 0, info.mss_now, tcp_sk(ssk)->nonagle,

			 info.size_goal);

		WRITE_ONCE(msk->allow_infinite_fallback, false);

	}



	release_sock(ssk);
@@ -2539,6 +2540,7 @@ static int __mptcp_init_sock(struct sock *sk) 
	msk->first = NULL;

	inet_csk(sk)->icsk_sync_mss = mptcp_sync_mss;

	WRITE_ONCE(msk->csum_enabled, mptcp_is_checksum_enabled(sock_net(sk)));

	WRITE_ONCE(msk->allow_infinite_fallback, true);

	msk->recovery = false;



	mptcp_pm_data_init(msk);
@@ -3275,6 +3277,7 @@ bool mptcp_finish_join(struct sock *ssk) 
	}



	subflow->map_seq = READ_ONCE(msk->ack_seq);

	WRITE_ONCE(msk->allow_infinite_fallback, false);



out:

	mptcp_event(MPTCP_EVENT_SUB_ESTABLISHED, msk, ssk, GFP_ATOMIC);

net/mptcp/protocol.h

+1 −0
Original line number Diff line number Diff line
@@ -263,6 +263,7 @@ struct mptcp_sock { 
	bool		rcv_fastclose;

	bool		use_64bit_ack; /* Set when we received a 64-bit DSN */

	bool		csum_enabled;

	bool		allow_infinite_fallback;

	u8		recvmsg_inq:1,

			cork:1,

			nodelay:1;

net/mptcp/subflow.c

+3 −1
Original line number Diff line number Diff line
@@ -1206,7 +1206,8 @@ static bool subflow_check_data_avail(struct sock *ssk) 
	if (!__mptcp_check_fallback(msk)) {

		/* RFC 8684 section 3.7. */

		if (subflow->send_mp_fail) {

			if (mptcp_has_another_subflow(ssk)) {

			if (mptcp_has_another_subflow(ssk) ||

			    !READ_ONCE(msk->allow_infinite_fallback)) {

				ssk->sk_err = EBADMSG;

				tcp_set_state(ssk, TCP_CLOSE);

				subflow->reset_transient = 0;
@@ -1486,6 +1487,7 @@ int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 
	/* discard the subflow socket */

	mptcp_sock_graft(ssk, sk->sk_socket);

	iput(SOCK_INODE(sf));

	WRITE_ONCE(msk->allow_infinite_fallback, false);

	return err;



failed_unlink: