From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4AC176E for ; Mon, 22 Mar 2021 23:11:00 +0000 (UTC) IronPort-SDR: wIkX7j2oNYwTwpkEbOI0yQeuFbGZtmJfIkmq+a7aUZKvVp5Ud7ZJpXpj/Uw+hy7WGi4lqFXSQY MKfdSWDhGkGQ== X-IronPort-AV: E=McAfee;i="6000,8403,9931"; a="177935766" X-IronPort-AV: E=Sophos;i="5.81,269,1610438400"; d="scan'208";a="177935766" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Mar 2021 16:10:59 -0700 IronPort-SDR: 7pXpE2A2+UQbNKLEE4BeM0/cGG7gBil7D6FDXNTxqPZVV4mj+b2n0YpCQayMip1n5e1kkQ1fSn f7ObTcoQAlRQ== X-IronPort-AV: E=Sophos;i="5.81,269,1610438400"; d="scan'208";a="408021194" Received: from shahinam-mobl2.amr.corp.intel.com ([10.252.128.161]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Mar 2021 16:10:55 -0700 Date: Mon, 22 Mar 2021 16:10:55 -0700 (PDT) From: Mat Martineau To: Geliang Tang cc: mptcp@lists.01.org, mptcp@lists.linux.dev Subject: Re: [MPTCP][PATCH mptcp-next 4/6] mptcp: add the DSS checksum sending In-Reply-To: <643a31ae30f00dd0d1d49834f6e996b3fe637c47.1616412490.git.geliangtang@gmail.com> Message-ID: <41604ba7-65b8-7675-3f12-bfb6c124c61d@linux.intel.com> References: <7ad133370d4bb939ba69e35203797494181873b0.1616412490.git.geliangtang@gmail.com> <33da8b854a7397e7ecc807b335a0c7e69e023ca6.1616412490.git.geliangtang@gmail.com> <643a31ae30f00dd0d1d49834f6e996b3fe637c47.1616412490.git.geliangtang@gmail.com> X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed On Mon, 22 Mar 2021, Geliang Tang wrote: > In mptcp_established_options_dss, use the new function > mptcp_generate_dss_csum to generate the DSS checksum value. > > In mptcp_write_options, send out DSS with the checksum value. > > Signed-off-by: Geliang Tang > --- > include/net/mptcp.h | 1 + > net/mptcp/options.c | 41 ++++++++++++++++++++++++++++++++++++++--- > net/mptcp/protocol.h | 7 +++++++ > 3 files changed, 46 insertions(+), 3 deletions(-) > > diff --git a/include/net/mptcp.h b/include/net/mptcp.h > index 36fb6907aa6f..869a6d98a72e 100644 > --- a/include/net/mptcp.h > +++ b/include/net/mptcp.h > @@ -32,6 +32,7 @@ struct mptcp_ext { > frozen:1, > reset_transient:1; > u8 reset_reason:4; > + u16 csum; > }; > > #define MPTCP_RM_IDS_MAX 8 > diff --git a/net/mptcp/options.c b/net/mptcp/options.c > index bdced173edff..69eb15ef9385 100644 > --- a/net/mptcp/options.c > +++ b/net/mptcp/options.c > @@ -521,6 +521,30 @@ static void mptcp_write_data_fin(struct mptcp_subflow_context *subflow, > } > } > > +static u16 mptcp_generate_dss_csum(struct sk_buff *skb) > +{ > + struct csum_pseudo_header header; > + struct mptcp_ext *mpext; > + __wsum csum; > + > + if (!skb) > + return 0; > + > + mpext = mptcp_get_ext(skb); > + if (!mpext || !mpext->use_map) > + return 0; > + > + header.data_seq = mpext->data_seq; > + header.subflow_seq = mpext->subflow_seq; > + header.data_len = mpext->data_len; > + header.csum = 0; > + > + csum = skb_checksum(skb, 0, skb->len, 0); > + csum = csum_partial(&header, sizeof(header), csum); > + > + return csum_fold(csum); > +} > + > static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb, > bool snd_data_fin_enable, > unsigned int *size, > @@ -544,8 +568,11 @@ static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb, > > remaining -= map_size; > dss_size = map_size; > - if (mpext) > + if (mpext) { > + if (msk->csum_reqd) > + mpext->csum = mptcp_generate_dss_csum(skb); > opts->ext_copy = *mpext; > + } > > if (skb && snd_data_fin_enable) > mptcp_write_data_fin(subflow, skb, &opts->ext_copy); > @@ -1304,6 +1331,9 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp, > flags |= MPTCP_DSS_HAS_MAP | MPTCP_DSS_DSN64; > if (mpext->data_fin) > flags |= MPTCP_DSS_DATA_FIN; > + > + if (mpext->csum) Instead of relying on a non-zero mpext->csum, what about using opts->csum_enabled instead? (Would have to make sure that flag is set in mptcp_out_options for data packets too) This would be more compatible with hardware offload if that gets added later. > + len += TCPOLEN_MPTCP_DSS_CHECKSUM; > } > > *ptr++ = mptcp_option(MPTCPOPT_DSS, len, 0, flags); > @@ -1323,8 +1353,13 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp, > ptr += 2; > put_unaligned_be32(mpext->subflow_seq, ptr); > ptr += 1; > - put_unaligned_be32(mpext->data_len << 16 | > - TCPOPT_NOP << 8 | TCPOPT_NOP, ptr); > + if (mpext->csum) { Same as above, want to test the same opts->csum_enabled value. > + put_unaligned_be32(mpext->data_len << 16 | > + mpext->csum, ptr); > + } else { > + put_unaligned_be32(mpext->data_len << 16 | > + TCPOPT_NOP << 8 | TCPOPT_NOP, ptr); > + } > } > } > > diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h > index 4fc4871595ef..f62cea8635f0 100644 > --- a/net/mptcp/protocol.h > +++ b/net/mptcp/protocol.h > @@ -333,6 +333,13 @@ static inline struct mptcp_data_frag *mptcp_rtx_head(const struct sock *sk) > return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); > } > > +struct csum_pseudo_header { > + u64 data_seq; > + u32 subflow_seq; > + u16 data_len; > + u16 csum; > +}; > + > struct mptcp_subflow_request_sock { > struct tcp_request_sock sk; > u16 mp_capable : 1, > -- > 2.30.2 -- Mat Martineau Intel