From nobody Wed Sep 17 20:11:36 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 BE66F1A3142 for ; Sat, 5 Jul 2025 11:17:53 +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=1751714274; cv=none; b=bR8ZwAdBnh+OHEmwbNSZ5s8sqi1Wt/KwCpbjtOXyaS8FO7toVT8bm2AtpcpYOvAZJdfxAnAvrYnecNymI6mk5qP35Ai5G/Yb7E5mnn9NQmfZRZgmzKnEkVOlFO5jQV9IWHvWOC5Wf0Hnuseljh0GKTRFdiY6aV1qPB0C1onNZPQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751714274; c=relaxed/simple; bh=hRCUEhN08EMVpMX4kydKoNPiApXRv+3k63TEoFppVQs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=tjm3edHat+4+/tb/4Kg13ulNZwOKpBMn6dic37GOHit7ks4BZ99eSuCtnQnzoGPuqsdz3F5XApa+rszeYazz/aApWfBMU7mEe90+dsr4Fgo0PoQLNwEhX+fDGaSW+5U7U8UPmmoPRWrrQpXopxjGtcfddrrbsPxGfPSuq3c1Imc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gh9aUNei; 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="gh9aUNei" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B597C4CEED; Sat, 5 Jul 2025 11:17:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1751714273; bh=hRCUEhN08EMVpMX4kydKoNPiApXRv+3k63TEoFppVQs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gh9aUNeiLR3Ohjk59R8RbgN65iEUzYKvYBw3z96SLrVm7I7LYxycwRY3BAe3pTsAv 2CNQVkJKMrX0jNQY6jtmYaTONBvHoCK4oObrHMR6TwPLCVWFFeCCrrGQ2QMT/OosqA xizDVhBo3Ju+ffEtV+Q30J/04A++8kmrOHC0vP6+S4mMwM3IzKdk7oyC4FUOOn+3gq 5nj6244uUEfIJL8GMi8KcTKYI3YD0au2f1z52+OWML2TMzwiGYZ/Yuv207pmmVA5Li ZX5RLInLSUEZb2T3Vx+ZFJ5JLKk31qvMacSjpmCG44tsmrJUDePlh03673jjKLFRTx ksxRdXeTDpOmw== From: Geliang Tang To: mptcp@lists.linux.dev, pabeni@redhat.com, hare@kernel.org Cc: Geliang Tang Subject: [PATCH mptcp-next v6 3/4] mptcp: implement .splice_read Date: Sat, 5 Jul 2025 19:17:41 +0800 Message-ID: <6ff0966262c7da64718a61dcb514829099c59e04.1751714072.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(). Signed-off-by: Geliang Tang --- net/mptcp/protocol.c | 136 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 136 insertions(+) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 7d58bb3f9fa3..327281ba5629 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -4023,6 +4023,140 @@ static int mptcp_read_sock(struct sock *sk, read_de= scriptor_t *desc, return copied; } =20 +/* + * MPTCP splice context + */ +struct mptcp_splice_state { + struct pipe_inode_info *pipe; + size_t len; + unsigned int flags; +}; + +static int mptcp_splice_data_recv(read_descriptor_t *rd_desc, struct sk_bu= ff *skb, + unsigned int offset, size_t len) +{ + struct mptcp_splice_state *mss =3D rd_desc->arg.data; + int ret; + + ret =3D skb_splice_bits(skb, skb->sk, offset, mss->pipe, + min(rd_desc->count, len), mss->flags); + if (ret > 0) + rd_desc->count -=3D ret; + return ret; +} + +static int __mptcp_splice_read(struct sock *sk, struct mptcp_splice_state = *mss) +{ + /* Store MPTCP splice context information in read_descriptor_t. */ + read_descriptor_t rd_desc =3D { + .arg.data =3D mss, + .count =3D mss->len, + }; + + return mptcp_read_sock(sk, &rd_desc, mptcp_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 mptcp_splice_state mss =3D { + .pipe =3D pipe, + .len =3D len, + .flags =3D flags, + }; + struct sock *sk =3D sock->sk; + ssize_t spliced; + long timeo; + int ret; + + /* + * We can't seek on a socket input + */ + if (unlikely(*ppos)) + return -ESPIPE; + + spliced =3D 0; + ret =3D 0; + + lock_sock(sk); + + timeo =3D sock_rcvtimeo(sk, sock->file->f_flags & O_NONBLOCK); + while (mss.len) { + ret =3D __mptcp_splice_read(sk, &mss); + if (ret < 0) { + break; + } else if (!ret) { + if (spliced) + break; + if (sock_flag(sk, SOCK_DONE)) + break; + if (sk->sk_err) { + ret =3D sock_error(sk); + break; + } + if (sk->sk_shutdown & RCV_SHUTDOWN) { + if (__mptcp_move_skbs(sk)) + continue; + break; + } + if (sk->sk_state =3D=3D TCP_CLOSE) { + ret =3D -ENOTCONN; + break; + } + if (!timeo) { + ret =3D -EAGAIN; + 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; + if (signal_pending(current)) { + ret =3D sock_intr_errno(timeo); + break; + } + continue; + } + mss.len -=3D ret; + spliced +=3D ret; + + if (!mss.len || !timeo) + break; + release_sock(sk); + lock_sock(sk); + + if (sk->sk_err || sk->sk_state =3D=3D TCP_CLOSE || + (sk->sk_shutdown & RCV_SHUTDOWN) || + signal_pending(current)) + 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, @@ -4044,6 +4178,7 @@ 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 { @@ -4149,6 +4284,7 @@ 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