Commit eaa2ffab authored by Paolo Abeni's avatar Paolo Abeni Committed by Jakub Kicinski
Browse files

mptcp: introduce MPTCP snd_nxt 



Track the next MPTCP sequence number used on xmit,
currently always equal to write_next.

Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent f0e6a4cf

net/mptcp/options.c

+2 −2
Original line number Diff line number Diff line
@@ -813,7 +813,7 @@ static void update_una(struct mptcp_sock *msk, 
		       struct mptcp_options_received *mp_opt)

{

	u64 new_snd_una, snd_una, old_snd_una = atomic64_read(&msk->snd_una);

	u64 write_seq = READ_ONCE(msk->write_seq);

	u64 snd_nxt = READ_ONCE(msk->snd_nxt);



	/* avoid ack expansion on update conflict, to reduce the risk of

	 * wrongly expanding to a future ack sequence number, which is way
@@ -822,7 +822,7 @@ static void update_una(struct mptcp_sock *msk, 
	new_snd_una = expand_ack(old_snd_una, mp_opt->data_ack, mp_opt->ack64);



	/* ACK for data not even sent yet? Ignore. */

	if (after64(new_snd_una, write_seq))

	if (after64(new_snd_una, snd_nxt))

		new_snd_una = old_snd_una;



	while (after64(new_snd_una, old_snd_una)) {

net/mptcp/protocol.c

+5 −2
Original line number Diff line number Diff line
@@ -834,7 +834,7 @@ static void mptcp_clean_una(struct sock *sk) 
	 * plain TCP

	 */

	if (__mptcp_check_fallback(msk))

		atomic64_set(&msk->snd_una, msk->write_seq);

		atomic64_set(&msk->snd_una, msk->snd_nxt);

	snd_una = atomic64_read(&msk->snd_una);



	list_for_each_entry_safe(dfrag, dtmp, &msk->rtx_queue, list) {
@@ -1338,6 +1338,7 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 


	release_sock(ssk);

out:

	msk->snd_nxt = msk->write_seq;

	ssk_check_wmem(msk);

	release_sock(sk);

	return copied ? : ret;
@@ -1629,7 +1630,7 @@ static void mptcp_retransmit_handler(struct sock *sk) 
{

	struct mptcp_sock *msk = mptcp_sk(sk);



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

	if (atomic64_read(&msk->snd_una) == READ_ONCE(msk->snd_nxt)) {

		mptcp_stop_timer(sk);

	} else {

		set_bit(MPTCP_WORK_RTX, &msk->flags);
@@ -2100,6 +2101,7 @@ struct sock *mptcp_sk_clone(const struct sock *sk, 
	WRITE_ONCE(msk->fully_established, false);



	msk->write_seq = subflow_req->idsn + 1;

	msk->snd_nxt = msk->write_seq;

	atomic64_set(&msk->snd_una, msk->write_seq);

	if (mp_opt->mp_capable) {

		msk->can_ack = true;
@@ -2409,6 +2411,7 @@ void mptcp_finish_connect(struct sock *ssk) 
	WRITE_ONCE(msk->remote_key, subflow->remote_key);

	WRITE_ONCE(msk->local_key, subflow->local_key);

	WRITE_ONCE(msk->write_seq, subflow->idsn + 1);

	WRITE_ONCE(msk->snd_nxt, msk->write_seq);

	WRITE_ONCE(msk->ack_seq, ack_seq);

	WRITE_ONCE(msk->can_ack, 1);

	atomic64_set(&msk->snd_una, msk->write_seq);

net/mptcp/protocol.h

+9 −8
Original line number Diff line number Diff line
@@ -92,6 +92,13 @@ 
#define MPTCP_FALLBACK_DONE	4

#define MPTCP_WORK_CLOSE_SUBFLOW 5



static inline bool before64(__u64 seq1, __u64 seq2)

{

	return (__s64)(seq1 - seq2) < 0;

}



#define after64(seq2, seq1)	before64(seq1, seq2)



struct mptcp_options_received {

	u64	sndr_key;

	u64	rcvr_key;
@@ -201,6 +208,7 @@ struct mptcp_sock { 
	u64		local_key;

	u64		remote_key;

	u64		write_seq;

	u64		snd_nxt;

	u64		ack_seq;

	u64		rcv_data_fin_seq;

	struct sock	*last_snd;
@@ -276,7 +284,7 @@ static inline struct mptcp_data_frag *mptcp_rtx_tail(const struct sock *sk) 
{

	struct mptcp_sock *msk = mptcp_sk(sk);



	if (list_empty(&msk->rtx_queue))

	if (!before64(msk->snd_nxt, atomic64_read(&msk->snd_una)))

		return NULL;



	return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list);
@@ -528,13 +536,6 @@ static inline struct mptcp_ext *mptcp_get_ext(struct sk_buff *skb) 
	return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP);

}



static inline bool before64(__u64 seq1, __u64 seq2)

{

	return (__s64)(seq1 - seq2) < 0;

}



#define after64(seq2, seq1)	before64(seq1, seq2)



void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops);



static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk)