| Message ID | 7d43c0b1c5f336641d9c8edef80cd0e37b93b668.1630656206.git.geliangtang@xiaomi.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Mat Martineau |
| Headers | show |
| Series | The infinite mapping support | expand |
On Fri, 3 Sep 2021, Geliang Tang wrote: > From: Geliang Tang <geliangtang@xiaomi.com> > > This patch added the infinite mapping sending logic. > > Added a new flag snd_infinite_mapping_enable in mptcp_sock. Set it true > when a single subflow is in use in mptcp_pm_mp_fail_received. > > In mptcp_sendmsg_frag, if this flag is true, call the new function > mptcp_update_infinite_mapping to set the infinite mapping. > > In mptcp_write_options, send out the infinite mapping and fallback to > a regular TCP. > > Signed-off-by: Geliang Tang <geliangtang@xiaomi.com> > --- > net/mptcp/options.c | 13 +++++++++++++ > net/mptcp/pm.c | 6 ++++++ > net/mptcp/protocol.c | 21 +++++++++++++++++++++ > net/mptcp/protocol.h | 1 + > 4 files changed, 41 insertions(+) > > diff --git a/net/mptcp/options.c b/net/mptcp/options.c > index 1ec6529c4326..e2df21246be7 100644 > --- a/net/mptcp/options.c > +++ b/net/mptcp/options.c > @@ -1326,6 +1326,19 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp, > put_unaligned_be32(mpext->data_len << 16 | > TCPOPT_NOP << 8 | TCPOPT_NOP, ptr); > } > + > + if (mpext->data_len == 0) { > + const struct sock *ssk = (const struct sock *)tp; > + struct mptcp_subflow_context *subflow; > + struct mptcp_sock *msk; > + > + subflow = mptcp_subflow_ctx(ssk); > + msk = mptcp_sk(subflow->conn); > + > + pr_debug("write infinite mapping!"); > + pr_fallback(msk); > + __mptcp_do_fallback(msk); > + } The fallback action shouldn't happen inside mptcp_write_options(). I have a suggestion below. > } > } else if ((OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | > OPTION_MPTCP_MPC_ACK) & opts->suboptions) { > diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c > index 6ab386ff3294..39f2dcda53bf 100644 > --- a/net/mptcp/pm.c > +++ b/net/mptcp/pm.c > @@ -251,7 +251,13 @@ void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup) > > void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq) > { > + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); > + struct mptcp_sock *msk = mptcp_sk(subflow->conn); > + > pr_debug("fail_seq=%llu", fail_seq); > + > + if (!mptcp_has_another_subflow(sk)) > + WRITE_ONCE(msk->snd_infinite_mapping_enable, true); Like patch 1, there needs to be a check for both "single subflow" and "contiguous data". > } > > /* path manager helpers */ > diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c > index faf6e7000d18..dd7738a6b7f5 100644 > --- a/net/mptcp/protocol.c > +++ b/net/mptcp/protocol.c > @@ -1282,6 +1282,22 @@ static void mptcp_update_data_checksum(struct sk_buff *skb, int added) > mpext->csum = csum_fold(csum_block_add(csum, skb_checksum(skb, offset, added, 0), offset)); > } > > +static void mptcp_update_infinite_mapping(struct mptcp_sock *msk, struct mptcp_ext *mpext) > +{ > + if (!mpext) > + return; > + > + mpext->data_seq = READ_ONCE(msk->ack_seq); RFC 8684 says the data_seq to use is "the start of the subflow sequence number of the most recent segment that was known to be delivered intact (i.e., was successfully DATA_ACKed)". In other words, the data_seq from the mapping that was for the *beginning* of the last fully-acked data segment. This is something else that we don't specifically keep track of yet. The necessary information is (all?) in the msk->rtx_queue - I think we will have to add something to the msk to keep track of the 64-bit sequence number of each mapping as they are acked. This would be updated in __mptcp_data_acked() or __mptcp_clean_una(). > + mpext->data_len = 0; I think it might work well to add an infinite_mapping field to struct mptcp_ext, and that could be checked in mptcp_established_options() to allow the DSS option to be written even if the fallback flag is set. > + if (READ_ONCE(msk->csum_enabled)) > + mpext->csum = 0; > + > + WRITE_ONCE(msk->snd_infinite_mapping_enable, false); > + > + pr_debug("infinite mapping: data_seq=%llu subflow_seq=%u data_len=%u dsn64=%d", > + mpext->data_seq, mpext->subflow_seq, mpext->data_len, mpext->dsn64); > +} > + > static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, > struct mptcp_data_frag *dfrag, > struct mptcp_sendmsg_info *info) > @@ -1390,6 +1406,10 @@ static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, > out: > if (READ_ONCE(msk->csum_enabled)) > mptcp_update_data_checksum(tail, ret); > + > + if (READ_ONCE(msk->snd_infinite_mapping_enable)) > + mptcp_update_infinite_mapping(msk, mpext); > + > mptcp_subflow_ctx(ssk)->rel_write_seq += ret; > return ret; > } > @@ -2858,6 +2878,7 @@ struct sock *mptcp_sk_clone(const struct sock *sk, > WRITE_ONCE(msk->fully_established, false); > if (mp_opt->suboptions & OPTION_MPTCP_CSUMREQD) > WRITE_ONCE(msk->csum_enabled, true); > + WRITE_ONCE(msk->snd_infinite_mapping_enable, false); > > msk->write_seq = subflow_req->idsn + 1; > msk->snd_nxt = msk->write_seq; > diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h > index 99a23fff7b03..33400fcdf1b1 100644 > --- a/net/mptcp/protocol.h > +++ b/net/mptcp/protocol.h > @@ -246,6 +246,7 @@ struct mptcp_sock { > bool fully_established; > bool rcv_data_fin; > bool snd_data_fin_enable; > + bool snd_infinite_mapping_enable; > bool rcv_fastclose; > bool use_64bit_ack; /* Set when we received a 64-bit DSN */ > bool csum_enabled; > -- > 2.31.1 > > > -- Mat Martineau Intel
diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 1ec6529c4326..e2df21246be7 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -1326,6 +1326,19 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp, put_unaligned_be32(mpext->data_len << 16 | TCPOPT_NOP << 8 | TCPOPT_NOP, ptr); } + + if (mpext->data_len == 0) { + const struct sock *ssk = (const struct sock *)tp; + struct mptcp_subflow_context *subflow; + struct mptcp_sock *msk; + + subflow = mptcp_subflow_ctx(ssk); + msk = mptcp_sk(subflow->conn); + + pr_debug("write infinite mapping!"); + pr_fallback(msk); + __mptcp_do_fallback(msk); + } } } else if ((OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | OPTION_MPTCP_MPC_ACK) & opts->suboptions) { diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index 6ab386ff3294..39f2dcda53bf 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -251,7 +251,13 @@ void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup) void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq) { + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); + struct mptcp_sock *msk = mptcp_sk(subflow->conn); + pr_debug("fail_seq=%llu", fail_seq); + + if (!mptcp_has_another_subflow(sk)) + WRITE_ONCE(msk->snd_infinite_mapping_enable, true); } /* path manager helpers */ diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index faf6e7000d18..dd7738a6b7f5 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1282,6 +1282,22 @@ static void mptcp_update_data_checksum(struct sk_buff *skb, int added) mpext->csum = csum_fold(csum_block_add(csum, skb_checksum(skb, offset, added, 0), offset)); } +static void mptcp_update_infinite_mapping(struct mptcp_sock *msk, struct mptcp_ext *mpext) +{ + if (!mpext) + return; + + mpext->data_seq = READ_ONCE(msk->ack_seq); + mpext->data_len = 0; + if (READ_ONCE(msk->csum_enabled)) + mpext->csum = 0; + + WRITE_ONCE(msk->snd_infinite_mapping_enable, false); + + pr_debug("infinite mapping: data_seq=%llu subflow_seq=%u data_len=%u dsn64=%d", + mpext->data_seq, mpext->subflow_seq, mpext->data_len, mpext->dsn64); +} + static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, struct mptcp_data_frag *dfrag, struct mptcp_sendmsg_info *info) @@ -1390,6 +1406,10 @@ static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, out: if (READ_ONCE(msk->csum_enabled)) mptcp_update_data_checksum(tail, ret); + + if (READ_ONCE(msk->snd_infinite_mapping_enable)) + mptcp_update_infinite_mapping(msk, mpext); + mptcp_subflow_ctx(ssk)->rel_write_seq += ret; return ret; } @@ -2858,6 +2878,7 @@ struct sock *mptcp_sk_clone(const struct sock *sk, WRITE_ONCE(msk->fully_established, false); if (mp_opt->suboptions & OPTION_MPTCP_CSUMREQD) WRITE_ONCE(msk->csum_enabled, true); + WRITE_ONCE(msk->snd_infinite_mapping_enable, false); msk->write_seq = subflow_req->idsn + 1; msk->snd_nxt = msk->write_seq; diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 99a23fff7b03..33400fcdf1b1 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -246,6 +246,7 @@ struct mptcp_sock { bool fully_established; bool rcv_data_fin; bool snd_data_fin_enable; + bool snd_infinite_mapping_enable; bool rcv_fastclose; bool use_64bit_ack; /* Set when we received a 64-bit DSN */ bool csum_enabled;