From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 36CC4C433DB for ; Mon, 22 Feb 2021 11:56:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CB73164E15 for ; Mon, 22 Feb 2021 11:56:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230124AbhBVLzc (ORCPT ); Mon, 22 Feb 2021 06:55:32 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:46238 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230010AbhBVLzK (ORCPT ); Mon, 22 Feb 2021 06:55:10 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613994821; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=uwBWTvI52wqLrpQP0Tt3FcCpkL+x02v8vMn3ChAyK8U=; b=Xm2xHlduC8T13SPIOt6JoKlpsz8FgUNEU6y2fcmib0/GFaWq8bSxmdsy0YDUf4VaIW20xk cbjpC8dQG4TtEhqDwb9v7pAWnZS/ydfINuEXDzGzT7vqWJxGEQ550tAEBXb89Bd5bwhnlP fjrDd1YLtuQLR71i1FwHHe1jNni7LGw= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-397-URXpIemqOreVOayVONWIOg-1; Mon, 22 Feb 2021 06:53:37 -0500 X-MC-Unique: URXpIemqOreVOayVONWIOg-1 Received: by mail-wm1-f70.google.com with SMTP id z67so4954687wme.3 for ; Mon, 22 Feb 2021 03:53:37 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=uwBWTvI52wqLrpQP0Tt3FcCpkL+x02v8vMn3ChAyK8U=; b=Wr3lcXIySv5LJslEnVzBKDINC94QcJIDIWzZRCuVNdKIxZQXA6TzDd5xeCp2VM2Ek7 bpy0Am23BLISpGvHB9T69hH77sWIeDPS+QPPXHhmiiq1lLgUCPXiYW0UQRGmXP9SuGlO BIrIrWESOGvbtFQ66+HAdXNBShl+Vo7623qxRIhIA2RT2wOWNWGepyJWp7HCVTJJhfq/ JvbOzHtYIjq6NYzFLSTI0ATPk2jcA6wFT5e6Gkj0OIB9XrBUueg1mvvn0uvXz4fybNLe xN43dKZ0/vbk424uW362r5o+IBKyRRIi9RBnNzjSUisX+Clm7HuFiVUEjRe6qAkD/HH6 CooA== X-Gm-Message-State: AOAM533CPGLiu7hwCx0mQsEsdtst8x++g5HasRWBsp1XU8xTo1l/OK0T 7UkspBF9dIuZLhvg+BrqELRluOlhjzDxHjmW/w9pZPeTDjm0QNAzK8RKc6tuCSqoyf4yvO7aEWe 6D93T+Es8/d/XsipHPIEbQ4dN X-Received: by 2002:adf:a2c7:: with SMTP id t7mr21259236wra.42.1613994816239; Mon, 22 Feb 2021 03:53:36 -0800 (PST) X-Google-Smtp-Source: ABdhPJwF3z2re71U2qX2sBvyIA4CC2xz2iu5FyqhwdzeqbDwD5LQo1ZoMCLS2hsoaBHr951kbzi9wg== X-Received: by 2002:adf:a2c7:: with SMTP id t7mr21259216wra.42.1613994816075; Mon, 22 Feb 2021 03:53:36 -0800 (PST) Received: from steredhat (host-79-34-249-199.business.telecomitalia.it. [79.34.249.199]) by smtp.gmail.com with ESMTPSA id v15sm28906877wra.61.2021.02.22.03.53.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Feb 2021 03:53:35 -0800 (PST) Date: Mon, 22 Feb 2021 12:53:32 +0100 From: Stefano Garzarella To: Arseny Krasnov Cc: Stefan Hajnoczi , "Michael S. Tsirkin" , Jason Wang , "David S. Miller" , Jakub Kicinski , Jorgen Hansen , Norbert Slusarek , Andra Paraschiv , Colin Ian King , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stsp2@yandex.ru, oxffffaa@gmail.com Subject: Re: [RFC PATCH v5 04/19] af_vsock: implement SEQPACKET receive loop Message-ID: <20210222115332.bmfwqzbytimk65ta@steredhat> References: <20210218053347.1066159-1-arseny.krasnov@kaspersky.com> <20210218053719.1067237-1-arseny.krasnov@kaspersky.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20210218053719.1067237-1-arseny.krasnov@kaspersky.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 18, 2021 at 08:37:15AM +0300, Arseny Krasnov wrote: >This adds receive loop for SEQPACKET. It looks like receive loop for >STREAM, but there is a little bit difference: >1) It doesn't call notify callbacks. >2) It doesn't care about 'SO_SNDLOWAT' and 'SO_RCVLOWAT' values, because > there is no sense for these values in SEQPACKET case. >3) It waits until whole record is received or error is found during > receiving. >4) It processes and sets 'MSG_TRUNC' flag. > >So to avoid extra conditions for two types of socket inside one loop, two >independent functions were created. > >Signed-off-by: Arseny Krasnov >--- > include/net/af_vsock.h | 5 +++ > net/vmw_vsock/af_vsock.c | 97 +++++++++++++++++++++++++++++++++++++++- > 2 files changed, 101 insertions(+), 1 deletion(-) > >diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h >index b1c717286993..01563338cc03 100644 >--- a/include/net/af_vsock.h >+++ b/include/net/af_vsock.h >@@ -135,6 +135,11 @@ struct vsock_transport { > bool (*stream_is_active)(struct vsock_sock *); > bool (*stream_allow)(u32 cid, u32 port); > >+ /* SEQ_PACKET. */ >+ size_t (*seqpacket_seq_get_len)(struct vsock_sock *vsk); >+ int (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, >+ int flags, bool *msg_ready); I think this should be: int (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, int flags, bool *msg_ready); To avoid: $ ./scripts/checkpatch.pl --strict -g HEAD CHECK: Alignment should match open parenthesis #35: FILE: include/net/af_vsock.h:141: + int (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, + int flags, bool *msg_ready); >+ > /* Notification. */ > int (*notify_poll_in)(struct vsock_sock *, size_t, bool *); > int (*notify_poll_out)(struct vsock_sock *, size_t, bool *); >diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c >index d277dc1cdbdf..b754927a556a 100644 >--- a/net/vmw_vsock/af_vsock.c >+++ b/net/vmw_vsock/af_vsock.c >@@ -1972,6 +1972,98 @@ static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, > return err; > } > >+static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, >+ size_t len, int flags) >+{ >+ const struct vsock_transport *transport; >+ const struct iovec *orig_iov; >+ unsigned long orig_nr_segs; >+ bool msg_ready; >+ struct vsock_sock *vsk; >+ size_t record_len; >+ long timeout; >+ int err = 0; >+ DEFINE_WAIT(wait); >+ >+ vsk = vsock_sk(sk); >+ transport = vsk->transport; >+ >+ timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); >+ orig_nr_segs = msg->msg_iter.nr_segs; >+ orig_iov = msg->msg_iter.iov; >+ msg_ready = false; >+ record_len = 0; >+ >+ while (1) { >+ err = vsock_wait_data(sk, &wait, timeout, NULL, 0); >+ >+ if (err <= 0) { >+ /* In case of any loop break(timeout, signal >+ * interrupt or shutdown), we report user that >+ * nothing was copied. >+ */ >+ err = 0; >+ break; >+ } >+ >+ if (record_len == 0) { >+ record_len = >+ transport->seqpacket_seq_get_len(vsk); >+ >+ if (record_len == 0) >+ continue; >+ } >+ >+ err = transport->seqpacket_dequeue(vsk, msg, >+ flags, &msg_ready); >+ Sorry, I expressed myself wrong. Here it's fine to avoid the blank line as in the previous version, by single line I meant the seqpacket_dequeue() call, something like this: err = transport->seqpacket_dequeue(vsk, msg, flags, &msg_ready); if (err < 0) { >+ if (err < 0) { >+ if (err == -EAGAIN) { >+ iov_iter_init(&msg->msg_iter, READ, >+ orig_iov, orig_nr_segs, >+ len); >+ /* Clear 'MSG_EOR' here, because dequeue >+ * callback above set it again if it was >+ * set by sender. This 'MSG_EOR' is from >+ * dropped record. >+ */ >+ msg->msg_flags &= ~MSG_EOR; >+ record_len = 0; >+ continue; >+ } >+ >+ err = -ENOMEM; >+ break; >+ } >+ >+ if (msg_ready) >+ break; >+ } >+ >+ if (sk->sk_err) >+ err = -sk->sk_err; >+ else if (sk->sk_shutdown & RCV_SHUTDOWN) >+ err = 0; >+ >+ if (msg_ready) { >+ /* User sets MSG_TRUNC, so return real length of >+ * packet. >+ */ >+ if (flags & MSG_TRUNC) >+ err = record_len; >+ else >+ err = len - msg->msg_iter.count; >+ >+ /* Always set MSG_TRUNC if real length of packet is >+ * bigger than user's buffer. >+ */ >+ if (record_len > len) >+ msg->msg_flags |= MSG_TRUNC; >+ } >+ >+ return err; >+} >+ > static int > vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, > int flags) >@@ -2027,7 +2119,10 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, > goto out; > } > >- err = __vsock_stream_recvmsg(sk, msg, len, flags); >+ if (sk->sk_type == SOCK_STREAM) >+ err = __vsock_stream_recvmsg(sk, msg, len, flags); >+ else >+ err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); > > out: > release_sock(sk); >-- >2.25.1 >