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,USER_AGENT_SANE_1 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 210E8C433E5 for ; Thu, 25 Mar 2021 16:03:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EBC2561A37 for ; Thu, 25 Mar 2021 16:03:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229944AbhCYQDJ (ORCPT ); Thu, 25 Mar 2021 12:03:09 -0400 Received: from mx12.kaspersky-labs.com ([91.103.66.155]:36091 "EHLO mx12.kaspersky-labs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229900AbhCYQC4 (ORCPT ); Thu, 25 Mar 2021 12:02:56 -0400 Received: from relay12.kaspersky-labs.com (unknown [127.0.0.10]) by relay12.kaspersky-labs.com (Postfix) with ESMTP id A6628769B2; Thu, 25 Mar 2021 19:02:53 +0300 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kaspersky.com; s=mail202102; t=1616688173; bh=RO1t5ueJP/AnptFtk+OAbsY0AzvoZeOtI+4YZ3NubDY=; h=Subject:To:From:Message-ID:Date:MIME-Version:Content-Type; b=HJTOrkYBapAaXySftjIQk1fiLYhzOEJMY/NTIoufvlSrbibuigVvamDmrf7z2pDKu E8ka1cu8jZiqr6TarzVgtfYFJ5HHZJ7gSdL3ERjVm9aqAKV3eZ9gvixY75PSCC+oiP KVSQzZcjIedcMfkPItV6Sic0nYwZ6FIk9KJk8opFgHakDlNse5DkQS1FPK9QcRWm/x YSldbTO+g1fRPGotAmSCU0viwOVv946vsg8hhzLI76JrOn6HLdaV4HwTtc64F9Tpea TzhaIRsG3A4rWwa0ldfZBIpS2vkOPXo7VQD1hIxDpjDpAMP3xOY5t6jCvcN3WgsKcM hFbDOsi3tgziQ== 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 63990769BB; Thu, 25 Mar 2021 19:02:53 +0300 (MSK) Received: from [10.16.171.77] (10.64.68.128) 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 19:02:52 +0300 Subject: Re: [RFC PATCH v7 12/22] virtio/vsock: fetch length for SEQPACKET record To: Stefano Garzarella CC: Stefan Hajnoczi , "Michael S. Tsirkin" , Jason Wang , "David S. Miller" , Jakub Kicinski , Jorgen Hansen , Andra Paraschiv , Colin Ian King , Norbert Slusarek , 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> <20210323131258.2461163-1-arseny.krasnov@kaspersky.com> <20210325100810.ygmg6vqb2f7rxoyx@steredhat> From: Arseny Krasnov Message-ID: Date: Thu, 25 Mar 2021 19:02:52 +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: <20210325100810.ygmg6vqb2f7rxoyx@steredhat> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.64.68.128] 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: 127.0.0.199:7.1.2;kaspersky.com:7.1.1;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 13:08, Stefano Garzarella wrote: > On Tue, Mar 23, 2021 at 04:12:55PM +0300, Arseny Krasnov wrote: >> This adds transport callback which tries to fetch record begin marker > >from socket's rx queue. It is called from af_vsock.c before reading data >> packets of record. >> >> Signed-off-by: Arseny Krasnov >> --- >> v6 -> v7: >> 1) Now 'virtio_transport_seqpacket_seq_get_len()' returns 0, if rx >> queue of socket is empty. Else it returns length of current message >> to handle. >> 2) If dequeue callback is called, but there is no detected length of >> message to dequeue, EAGAIN is returned, and outer loop restarts >> receiving. >> >> net/vmw_vsock/virtio_transport_common.c | 61 +++++++++++++++++++++++++ >> 1 file changed, 61 insertions(+) >> >> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c >> index a8f4326e45e8..41f05034593e 100644 >> --- a/net/vmw_vsock/virtio_transport_common.c >> +++ b/net/vmw_vsock/virtio_transport_common.c >> @@ -399,6 +399,62 @@ static inline void virtio_transport_remove_pkt(struct virtio_vsock_pkt *pkt) >> virtio_transport_free_pkt(pkt); >> } >> >> +static size_t virtio_transport_drop_until_seq_begin(struct >> virtio_vsock_sock *vvs) >> +{ >> + struct virtio_vsock_pkt *pkt, *n; >> + size_t bytes_dropped = 0; >> + >> + list_for_each_entry_safe(pkt, n, &vvs->rx_queue, list) { >> + if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_SEQ_BEGIN) >> + break; >> + >> + bytes_dropped += le32_to_cpu(pkt->hdr.len); >> + virtio_transport_dec_rx_pkt(vvs, pkt); >> + virtio_transport_remove_pkt(pkt); >> + } >> + >> + return bytes_dropped; >> +} >> + >> +static size_t virtio_transport_seqpacket_seq_get_len(struct vsock_sock *vsk) >> +{ >> + struct virtio_vsock_seq_hdr *seq_hdr; >> + struct virtio_vsock_sock *vvs; >> + struct virtio_vsock_pkt *pkt; >> + size_t bytes_dropped = 0; >> + >> + vvs = vsk->trans; >> + >> + spin_lock_bh(&vvs->rx_lock); >> + >> + /* Have some record to process, return it's length. */ >> + if (vvs->seq_state.user_read_seq_len) >> + goto out; >> + >> + /* Fetch all orphaned 'RW' packets and send credit update. */ >> + bytes_dropped = virtio_transport_drop_until_seq_begin(vvs); >> + >> + if (list_empty(&vvs->rx_queue)) >> + goto out; >> + >> + pkt = list_first_entry(&vvs->rx_queue, struct virtio_vsock_pkt, list); >> + >> + vvs->seq_state.user_read_copied = 0; >> + >> + seq_hdr = (struct virtio_vsock_seq_hdr *)pkt->buf; >> + vvs->seq_state.user_read_seq_len = le32_to_cpu(seq_hdr->msg_len); >> + vvs->seq_state.curr_rx_msg_id = le32_to_cpu(seq_hdr->msg_id); >> + virtio_transport_dec_rx_pkt(vvs, pkt); >> + virtio_transport_remove_pkt(pkt); >> +out: >> + spin_unlock_bh(&vvs->rx_lock); >> + >> + if (bytes_dropped) >> + virtio_transport_send_credit_update(vsk); >> + >> + return vvs->seq_state.user_read_seq_len; >> +} >> + >> static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk, >> struct msghdr *msg, >> bool *msg_ready) >> @@ -522,6 +578,11 @@ virtio_transport_seqpacket_dequeue(struct vsock_sock *vsk, >> if (flags & MSG_PEEK) >> return -EOPNOTSUPP; >> >> + *msg_len = virtio_transport_seqpacket_seq_get_len(vsk); >> + >> + if (*msg_len == 0) >> + return -EAGAIN; >> + > Okay, I see now, I think you can move this patch before the previous one > or merge them in a single patch, it is better to review and to bisect. > > As mentioned, I think we can return msg_len if > virtio_transport_seqpacket_do_dequeue() does not fail, otherwise the > error. > > I mean something like this: > > static ssize_t virtio_transport_seqpacket_do_dequeue(...) > { > size_t msg_len; > ssize_t ret; > > msg_len = virtio_transport_seqpacket_seq_get_len(vsk); > if (msg_len == 0) > return -EAGAIN; > > ret = virtio_transport_seqpacket_do_dequeue(vsk, msg, msg_ready); > if (ret < 0) > return ret; > > return msg_len; > } Ack > >> return virtio_transport_seqpacket_do_dequeue(vsk, msg, msg_ready); >> } >> EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_dequeue); >> -- 2.25.1 >> >