From nobody Wed Sep 17 18:22:23 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 A8A2B38FB9 for ; Sat, 13 Sep 2025 00:39:14 +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=1757723954; cv=none; b=e8bmIhVQBjcI0TnKPde+GithfbyyftDzcZUReYqCn5I3iuMzz2Ss/gx6dRu8DDGeFaaasU72OrMnkDqsxTPrY7Uxh9/l+P/bb82VxGyTdUWQqV/vQ3QIDki55BMWqukbAngQBCyDGJAJ4R2iEg8o7BeU9a4QMayiYSZlrxMh1UQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757723954; c=relaxed/simple; bh=hVytNSo+mu0v8CingI4PDIDyZxovCRQMQAw5ri6gn20=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=s/4CiYrxPbVEQK1PtiXHiyJb4xFn8suIJc3t4K/1yB81DhJYDYn/flKZF0mK4Fk6Kgax07TdyPJ93HPvvtv3/VN5tjjTsLasVQrlErQrCbSYbR42mRiSdPooZQ+/4fPDHUrKHFokgUY2wfPOlqgGNDprpRhMrKUDBJqCTOprKEU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dSVyGA/V; 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="dSVyGA/V" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79D47C4CEF5; Sat, 13 Sep 2025 00:39:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757723954; bh=hVytNSo+mu0v8CingI4PDIDyZxovCRQMQAw5ri6gn20=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dSVyGA/VGJM+VWJa33YFAJUs9Le0E5Mad7TsfEUkMeu+dSmsk2h3EbwYfHgnIOT39 ZhI23uXgJ4duXhxcsZRz9EzSYe70fOG3emjYgxmU4JM8D2m5U8/syQIPwsOHxlFimM Wcxnxx9ctVhph6oiCt1+tLOq6pN2Bj8wyfM55wmE1WuUqm2Z1EGfxwFcCkCWvv9Rbf 0ql24640Uou9uqWyN15/CWSPXvDSnTpO6/J3KNcAv8F/A96KN/pXZBrEee4AluXI3Z ioYhz3eXfvGWcVPii26WPOErkikkRLu2hocds+C1/s6/yopWb7Nnehj9ak7tYK8jYq uhWz9bPDq1YRQ== From: Geliang Tang To: mptcp@lists.linux.dev, hare@kernel.org Cc: Geliang Tang Subject: [PATCH mptcp-next v11 6/8] mptcp: implement .splice_read Date: Sat, 13 Sep 2025 08:37:25 +0800 Message-ID: <206b6c3dfd40468128dc11b52620230af492d58c.1757723270.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 This patch implements .splice_read interface of mptcp struct proto_ops as mptcp_splice_read() with reference to tcp_splice_read(). Corresponding to __tcp_splice_read(), __mptcp_splice_read() is defined, invoking mptcp_read_sock() instead of tcp_read_sock(). mptcp_splice_read() is almost the same as tcp_splice_read(), except for sock_rps_record_flow() and __mptcp_move_skbs(). Signed-off-by: Geliang Tang --- net/mptcp/protocol.c | 98 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 98 insertions(+) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 2288ceda45ce..8259cc74c7b2 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -4103,6 +4103,102 @@ static int mptcp_read_sock(struct sock *sk, read_de= scriptor_t *desc, return copied; } =20 +static int __mptcp_splice_read(struct sock *sk, struct tcp_splice_state *t= ss) +{ + /* Store TCP splice context information in read_descriptor_t. */ + read_descriptor_t rd_desc =3D { + .arg.data =3D tss, + .count =3D tss->len, + }; + + return mptcp_read_sock(sk, &rd_desc, tcp_splice_data_recv); +} + +/** + * mptcp_splice_read - splice data from MPTCP socket to a pipe + * @sock: socket to splice from + * @ppos: position (not valid) + * @pipe: pipe to splice to + * @len: number of bytes to splice + * @flags: splice modifier flags + * + * Description: + * Will read pages from given socket and fill them into a pipe. + * + **/ +static ssize_t mptcp_splice_read(struct socket *sock, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags) +{ + struct tcp_splice_state tss =3D { + .pipe =3D pipe, + .len =3D len, + .flags =3D flags, + }; + struct sock *sk =3D sock->sk; + ssize_t spliced =3D 0; + int ret =3D 0, err; + long timeo; + + /* + * We can't seek on a socket input + */ + if (unlikely(*ppos)) + return -ESPIPE; + + lock_sock(sk); + + mptcp_rps_record_subflows(mptcp_sk(sk)); + + timeo =3D sock_rcvtimeo(sk, sock->file->f_flags & O_NONBLOCK); + while (tss.len) { + ret =3D __mptcp_splice_read(sk, &tss); + if (ret < 0) { + break; + } else if (!ret) { + if (spliced) + break; + err =3D tcp_recv_should_stop(sk, timeo); + if (err < 0) { + if (err =3D=3D -ESHUTDOWN) { + if (__mptcp_move_skbs(sk)) + continue; + break; + } + ret =3D err; + break; + } + /* if __mptcp_splice_read() got nothing while we have + * an skb in receive queue, we do not want to loop. + * This might happen with URG data. + */ + if (!skb_queue_empty(&sk->sk_receive_queue)) + break; + ret =3D sk_wait_data(sk, &timeo, NULL); + if (ret < 0) + break; + continue; + } + tss.len -=3D ret; + spliced +=3D ret; + + if (!tss.len || !timeo) + break; + release_sock(sk); + lock_sock(sk); + + if (tcp_recv_should_stop(sk, timeo)) + break; + } + + release_sock(sk); + + if (spliced) + return spliced; + + return ret; +} + static const struct proto_ops mptcp_stream_ops =3D { .family =3D PF_INET, .owner =3D THIS_MODULE, @@ -4124,6 +4220,7 @@ static const struct proto_ops mptcp_stream_ops =3D { .mmap =3D sock_no_mmap, .set_rcvlowat =3D mptcp_set_rcvlowat, .read_sock =3D mptcp_read_sock, + .splice_read =3D mptcp_splice_read, }; =20 static struct inet_protosw mptcp_protosw =3D { @@ -4229,6 +4326,7 @@ static const struct proto_ops mptcp_v6_stream_ops =3D= { #endif .set_rcvlowat =3D mptcp_set_rcvlowat, .read_sock =3D mptcp_read_sock, + .splice_read =3D mptcp_splice_read, }; =20 static struct proto mptcp_v6_prot; --=20 2.48.1