From nobody Wed Sep 17 19:38:44 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 4F0144A08 for ; Sat, 28 Jun 2025 06:58:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751093882; cv=none; b=edRv/AtoTiPzx/EfY0t8L7CpExke+2WUHvT+LOo0v3cQ4kyjFcF1SdVq3dqIyoJofYzQx4YAWDc3Jz/5/UtaAHreMVTCbvTiTv2euZ/MDyes++J1gMd7650r0qF/49IlXSZpu7D1SHIgr65Cv6O2yghwCUy4kyjlJ3sMDK2Y4LA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751093882; c=relaxed/simple; bh=vBCSHusMthd3wYqtglA1rZINZLF8DuQCY7RGbljju3U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rBhLKK8kct4GQsmzTzMPNmO5JNVsjNZjeEukAqsaUwdmqu4zMdzTvCQzgTMOM0jub4My3d0ecgf6FSciK7WOKAw3p/2tVDe6iEiyZUT4vWw83TGCAmggz9dMn22k2S28RLQ5/8TwAMWcBlnbCaC85OsMwxHOrjTe8fkwIE2pH50= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t7hNErgi; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="t7hNErgi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ABF2FC4CEEE; Sat, 28 Jun 2025 06:58:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1751093881; bh=vBCSHusMthd3wYqtglA1rZINZLF8DuQCY7RGbljju3U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t7hNErgiY4hyromYyQJqjECycgsc6+bsHo8TXFOiggYLWXs7QZ5zYoItQPR2o55LD DPqradS2HivOgtdV3Vn5+KmHJjAxUSsteEWYRNTeHVXgna3qjwSXNu95IJ6L+ifpFe 8siAsScteK5Gl+sJMN6mjXV7S+A0aSyVTUKnnYdYzyZJSBoNAd5QZbOF2LrwonIfpL Aw9zv3iLT6ub8ktdBVQcEj+h6X+A/LYVzmiTbVdnAhH4ccxbCqtS5gHq/9BK2VJiC4 lxEGSrVGLJpgT2PjAEj3KuBUJ+REn+XD/idcs35h+NATXN84VXZiOjUm4e/cN5p/h+ SW66NSXJ1GsbQ== From: Geliang Tang To: mptcp@lists.linux.dev, hare@kernel.org Cc: Geliang Tang Subject: [PATCH mptcp-next v5 2/5] mptcp: add recvmsg_desc helper Date: Sat, 28 Jun 2025 14:57:10 +0800 Message-ID: <5fcd0bddfcdca24ebe9b0ff66cad0913235a4df9.1751093346.git.tanggeliang@kylinos.cn> X-Mailer: git-send-email 2.48.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Geliang Tang In order to implement .read_sock interface of mptcp later, this patch extends __mptcp_recvmsg_mskq() to a more general __mptcp_recvmsg_desc(), which accepts read_descriptor_t and sk_read_actor_t parameters. In this way, the original __mptcp_recvmsg_mskq() can be implemented by passing a newly defined mptcp_recvmsg_actor() to __mptcp_recvmsg_desc(). This mptcp_recvmsg_actor() is a wrapper for skb_copy_datagram_msg(). Signed-off-by: Geliang Tang --- net/mptcp/protocol.c | 37 +++++++++++++++++++++++++++++++++---- 1 file changed, 33 insertions(+), 4 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 2f747ab730e5..2ebdad6b233d 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1844,8 +1844,9 @@ static int mptcp_sendmsg(struct sock *sk, struct msgh= dr *msg, size_t len) =20 static void mptcp_rcv_space_adjust(struct mptcp_sock *msk, int copied); =20 -static int __mptcp_recvmsg_mskq(struct sock *sk, - struct msghdr *msg, +static int __mptcp_recvmsg_desc(struct sock *sk, + read_descriptor_t *desc, + sk_read_actor_t recv_actor, size_t len, int flags, struct scm_timestamping_internal *tss, int *cmsg_flags) @@ -1861,12 +1862,14 @@ static int __mptcp_recvmsg_mskq(struct sock *sk, int err; =20 if (!(flags & MSG_TRUNC)) { - err =3D skb_copy_datagram_msg(skb, offset, msg, count); - if (unlikely(err < 0)) { + err =3D recv_actor(desc, skb, offset, count); + if (err <=3D 0) { if (!copied) return err; break; } + if (!WARN_ON_ONCE(err > count)) + count =3D err; } =20 if (MPTCP_SKB_CB(skb)->has_rxtstamp) { @@ -1902,6 +1905,32 @@ static int __mptcp_recvmsg_mskq(struct sock *sk, return copied; } =20 +static int mptcp_recvmsg_actor(read_descriptor_t *rd_desc, struct sk_buff = *skb, + unsigned int offset, size_t len) +{ + struct msghdr *msg =3D rd_desc->arg.data; + int err; + + err =3D skb_copy_datagram_msg(skb, offset, msg, len); + if (unlikely(err < 0)) + return err; + return len; +} + +static int __mptcp_recvmsg_mskq(struct sock *sk, + struct msghdr *msg, + size_t len, int flags, + struct scm_timestamping_internal *tss, + int *cmsg_flags) +{ + read_descriptor_t desc =3D { + .arg.data =3D msg, + }; + + return __mptcp_recvmsg_desc(sk, &desc, mptcp_recvmsg_actor, + len, flags, tss, cmsg_flags); +} + /* receive buffer autotuning. See tcp_rcv_space_adjust for more informati= on. * * Only difference: Use highest rtt estimate of the subflows in use. --=20 2.48.1