Commit 16a9a9da authored by Mat Martineau's avatar Mat Martineau Committed by David S. Miller
Browse files

mptcp: Add helper to process acks of DATA_FIN 



After DATA_FIN has been sent, the peer will acknowledge it. An ack of
the relevant MPTCP-level sequence number will update the MPTCP
connection state appropriately.

Signed-off-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6920b851

net/mptcp/protocol.c

+46 −8
Original line number Diff line number Diff line
@@ -143,6 +143,14 @@ static void __mptcp_move_skb(struct mptcp_sock *msk, struct sock *ssk, 
	MPTCP_SKB_CB(skb)->offset = offset;

}



static void mptcp_stop_timer(struct sock *sk)

{

	struct inet_connection_sock *icsk = inet_csk(sk);



	sk_stop_timer(sk, &icsk->icsk_retransmit_timer);

	mptcp_sk(sk)->timer_ival = 0;

}



/* both sockets must be locked */

static bool mptcp_subflow_dsn_valid(const struct mptcp_sock *msk,

				    struct sock *ssk)
@@ -164,6 +172,42 @@ static bool mptcp_subflow_dsn_valid(const struct mptcp_sock *msk, 
	return mptcp_subflow_data_available(ssk);

}



static void mptcp_check_data_fin_ack(struct sock *sk)

{

	struct mptcp_sock *msk = mptcp_sk(sk);



	if (__mptcp_check_fallback(msk))

		return;



	/* Look for an acknowledged DATA_FIN */

	if (((1 << sk->sk_state) &

	     (TCPF_FIN_WAIT1 | TCPF_CLOSING | TCPF_LAST_ACK)) &&

	    msk->write_seq == atomic64_read(&msk->snd_una)) {

		mptcp_stop_timer(sk);



		WRITE_ONCE(msk->snd_data_fin_enable, 0);



		switch (sk->sk_state) {

		case TCP_FIN_WAIT1:

			inet_sk_state_store(sk, TCP_FIN_WAIT2);

			sk->sk_state_change(sk);

			break;

		case TCP_CLOSING:

			fallthrough;

		case TCP_LAST_ACK:

			inet_sk_state_store(sk, TCP_CLOSE);

			sk->sk_state_change(sk);

			break;

		}



		if (sk->sk_shutdown == SHUTDOWN_MASK ||

		    sk->sk_state == TCP_CLOSE)

			sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP);

		else

			sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);

	}

}



static bool mptcp_pending_data_fin(struct sock *sk, u64 *seq)

{

	struct mptcp_sock *msk = mptcp_sk(sk);
@@ -222,6 +266,8 @@ static void mptcp_check_data_fin(struct sock *sk) 
		WRITE_ONCE(msk->rcv_data_fin, 0);



		sk->sk_shutdown |= RCV_SHUTDOWN;

		smp_mb__before_atomic(); /* SHUTDOWN must be visible first */

		set_bit(MPTCP_DATA_READY, &msk->flags);



		switch (sk->sk_state) {

		case TCP_ESTABLISHED:
@@ -455,14 +501,6 @@ static void mptcp_check_for_eof(struct mptcp_sock *msk) 
	}

}



static void mptcp_stop_timer(struct sock *sk)

{

	struct inet_connection_sock *icsk = inet_csk(sk);



	sk_stop_timer(sk, &icsk->icsk_retransmit_timer);

	mptcp_sk(sk)->timer_ival = 0;

}



static bool mptcp_ext_cache_refill(struct mptcp_sock *msk)

{

	const struct sock *sk = (const struct sock *)msk;

CRA Git | Maintained and supported by SUSTech CRA and CCSE