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=-17.5 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,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 AC003C433DB for ; Thu, 25 Mar 2021 16:02:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6075161A1F for ; Thu, 25 Mar 2021 16:02:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229782AbhCYQCA (ORCPT ); Thu, 25 Mar 2021 12:02:00 -0400 Received: from mx12.kaspersky-labs.com ([91.103.66.155]:34910 "EHLO mx12.kaspersky-labs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229639AbhCYQBk (ORCPT ); Thu, 25 Mar 2021 12:01:40 -0400 Received: from relay12.kaspersky-labs.com (unknown [127.0.0.10]) by relay12.kaspersky-labs.com (Postfix) with ESMTP id 7F83A774AF; Thu, 25 Mar 2021 19:01:31 +0300 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kaspersky.com; s=mail202102; t=1616688091; bh=GaY4v6SLTMWQV0TO/GqAJWo5gYlwZP1bauQplvh/hnY=; h=Subject:To:From:Message-ID:Date:MIME-Version:Content-Type; b=ntpbRg4nlFVgOFjRTcmH1LjMSKt8w1JnL008KmxJsgZjhUtWm28BE0Dqq8SdZVb81 e7qvh4HOoOMytrcO4ufuN58NeV+JfO+85gay4KkbtU5NOYUdzLdTVhTmotWbZqNgAp 6ilRnefsklDqTuCSuDwNE6NzAO4BBjO/+UazWC6L3Hc3btZnpFW1jNhXHEeCUz4YOh WpkJEyCo0wi+oFSh2VZUrcMiCb2gH6YY6htx314y1CX1BcVbf6FQIAS4lhEKKBICgx YG6V3gzSpUWSUu9aSGsr1VoKjgADXuIyR44SSG3fQwNYhHRP8Cuz15ev4LfWGf5Oen LlMgmn8qazO7A== Received: from mail-hq2.kaspersky.com (unknown [91.103.66.206]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (Client CN "mail-hq2.kaspersky.com", Issuer "Kaspersky MailRelays CA G3" (verified OK)) by mailhub12.kaspersky-labs.com (Postfix) with ESMTPS id 4C9EA7749C; Thu, 25 Mar 2021 19:01:30 +0300 (MSK) Received: from [10.16.171.77] (10.64.64.121) by hqmailmbx3.avp.ru (10.64.67.243) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Thu, 25 Mar 2021 19:01:28 +0300 Subject: Re: [RFC PATCH v7 04/22] af_vsock: implement SEQPACKET receive loop To: Stefano Garzarella CC: Stefan Hajnoczi , "Michael S. Tsirkin" , Jason Wang , "David S. Miller" , Jakub Kicinski , Jorgen Hansen , Andra Paraschiv , Norbert Slusarek , Colin Ian King , Jeff Vander Stoep , Alexander Popov , "kvm@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "stsp2@yandex.ru" , "oxffffaa@gmail.com" References: <20210323130716.2459195-1-arseny.krasnov@kaspersky.com> <20210323131006.2460058-1-arseny.krasnov@kaspersky.com> <20210325093415.mpysybt5vfnsl7fg@steredhat> From: Arseny Krasnov Message-ID: Date: Thu, 25 Mar 2021 19:01:28 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210325093415.mpysybt5vfnsl7fg@steredhat> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.64.64.121] X-ClientProxiedBy: hqmailmbx3.avp.ru (10.64.67.243) To hqmailmbx3.avp.ru (10.64.67.243) X-KSE-ServerInfo: hqmailmbx3.avp.ru, 9 X-KSE-AntiSpam-Interceptor-Info: scan successful X-KSE-AntiSpam-Version: 5.9.20, Database issued on: 03/25/2021 15:37:01 X-KSE-AntiSpam-Status: KAS_STATUS_NOT_DETECTED X-KSE-AntiSpam-Method: none X-KSE-AntiSpam-Rate: 0 X-KSE-AntiSpam-Info: Lua profiles 162675 [Mar 25 2021] X-KSE-AntiSpam-Info: LuaCore: 438 438 e169a60cee0e977a975a890ed8ef829a2851344a X-KSE-AntiSpam-Info: Version: 5.9.20.0 X-KSE-AntiSpam-Info: Envelope from: arseny.krasnov@kaspersky.com X-KSE-AntiSpam-Info: {Tracking_from_domain_doesnt_match_to} X-KSE-AntiSpam-Info: kaspersky.com:7.1.1;127.0.0.199:7.1.2;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1 X-KSE-AntiSpam-Info: Rate: 0 X-KSE-AntiSpam-Info: Status: not_detected X-KSE-AntiSpam-Info: Method: none X-KSE-Antiphishing-Info: Clean X-KSE-Antiphishing-ScanningType: Deterministic X-KSE-Antiphishing-Method: None X-KSE-Antiphishing-Bases: 03/25/2021 15:40:00 X-KSE-AttachmentFiltering-Interceptor-Info: no applicable attachment filtering rules found X-KSE-Antivirus-Interceptor-Info: scan successful X-KSE-Antivirus-Info: Clean, bases: 25.03.2021 15:18:00 X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit X-KSE-AttachmentFiltering-Interceptor-Info: no applicable attachment filtering rules found X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit X-KLMS-Rule-ID: 52 X-KLMS-Message-Action: clean X-KLMS-AntiSpam-Status: not scanned, disabled by settings X-KLMS-AntiSpam-Interceptor-Info: not scanned X-KLMS-AntiPhishing: Clean, bases: 2021/03/25 14:47:00 X-KLMS-AntiVirus: Kaspersky Security for Linux Mail Server, version 8.0.3.30, bases: 2021/03/25 13:43:00 #16496755 X-KLMS-AntiVirus-Status: Clean, skipped Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25.03.2021 12:34, Stefano Garzarella wrote: > On Tue, Mar 23, 2021 at 04:10:03PM +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 >> --- >> v6 -> v7: >> 'seqpacket_get_len' callback now removed, length of message is returned >> by 'seqpacket_dequeue' callback. >> >> include/net/af_vsock.h | 4 ++ >> net/vmw_vsock/af_vsock.c | 88 +++++++++++++++++++++++++++++++++++++++- >> 2 files changed, 91 insertions(+), 1 deletion(-) >> >> diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h >> index b1c717286993..74ac8a4c4168 100644 >> --- a/include/net/af_vsock.h >> +++ b/include/net/af_vsock.h >> @@ -135,6 +135,10 @@ struct vsock_transport { >> bool (*stream_is_active)(struct vsock_sock *); >> bool (*stream_allow)(u32 cid, u32 port); >> >> + /* SEQ_PACKET. */ >> + int (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, >> + int flags, bool *msg_ready, size_t *record_len); >> + > Why not using ssize_t as return value and return the length or a > negative value in case of error? > > In this way we can remove the 'record_len' parameter. Ok, i think it is possible > >> /* 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 0bc661e54262..fa0c37f97330 100644 >> --- a/net/vmw_vsock/af_vsock.c >> +++ b/net/vmw_vsock/af_vsock.c >> @@ -1973,6 +1973,89 @@ 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; >> + } >> + >> + err = transport->seqpacket_dequeue(vsk, msg, flags, &msg_ready, &record_len); >> + >> + 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) { > If 'err' is not 0, should we skip this branch? Ack > >> + /* 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) >> @@ -2028,7 +2111,10 @@ 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 >> >