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 81098C433E0 for ; Thu, 25 Mar 2021 16:03:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4C7F661A1A for ; Thu, 25 Mar 2021 16:03:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229908AbhCYQDF (ORCPT ); Thu, 25 Mar 2021 12:03:05 -0400 Received: from mx13.kaspersky-labs.com ([91.103.66.164]:15295 "EHLO mx13.kaspersky-labs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229631AbhCYQCa (ORCPT ); Thu, 25 Mar 2021 12:02:30 -0400 Received: from relay13.kaspersky-labs.com (unknown [127.0.0.10]) by relay13.kaspersky-labs.com (Postfix) with ESMTP id 4D6FA52190E; Thu, 25 Mar 2021 19:02:27 +0300 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kaspersky.com; s=mail202102; t=1616688147; bh=utEKFQWw51QLyrDrgZJN35f3SBUwp5SWcZF11LdrQUY=; h=Subject:To:From:Message-ID:Date:MIME-Version:Content-Type; b=GoHwjENLxG8lxct/H8s2NXFGS55erPDbRLPzNNIEVUbB0qY6UqE3mYs6kyz/Ov5hT 9TEsyhrtaUrfpWhPp710AF1Iw/9SPpTt06EH4Wq+PUvOiATLvwNCahKnqkCOXNNp47 FMXRr810W29l9siLTg8322h/gw9N+o3CXXp7UyRQv/FCqcS0fG8hCyF8dsePRe66kQ CuYUORlvsKJY/EUNoODiITvTWyErtKi5mBGrDtOPXxfY85WvhwCFd/8rtWNsJN5KAO /30i/ABIElClz9/DWhk+FWyvcrh/Q9GDrMWDZwiQ7Zqt07jkcYK6E7pFEpblaepOjb aL7BzgyNwMU9Q== 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 mailhub13.kaspersky-labs.com (Postfix) with ESMTPS id 61625521925; Thu, 25 Mar 2021 19:02:26 +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 19:02:25 +0300 Subject: Re: [RFC PATCH v7 11/22] virtio/vsock: dequeue callback for SOCK_SEQPACKET 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 , 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> <20210323131244.2461050-1-arseny.krasnov@kaspersky.com> <20210325095623.q44wr2ymavq7axtv@steredhat> From: Arseny Krasnov Message-ID: <876a149d-f37e-bc03-f8dd-ce33f9d24890@kaspersky.com> Date: Thu, 25 Mar 2021 19:02:25 +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: <20210325095623.q44wr2ymavq7axtv@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 12:56, Stefano Garzarella wrote: > On Tue, Mar 23, 2021 at 04:12:41PM +0300, Arseny Krasnov wrote: >> This adds transport callback and it's logic for SEQPACKET dequeue. >> Callback fetches RW packets from rx queue of socket until whole record >> is copied(if user's buffer is full, user is not woken up). This is done >> to not stall sender, because if we wake up user and it leaves syscall, >> nobody will send credit update for rest of record, and sender will wait >> for next enter of read syscall at receiver's side. So if user buffer is >> full, we just send credit update and drop data. If during copy SEQ_BEGIN >> was found(and not all data was copied), copying is restarted by reset >> user's iov iterator(previous unfinished data is dropped). >> >> Signed-off-by: Arseny Krasnov >> --- >> v6 -> v7: >> 1) 'struct virtio_vsock_seqpacket_state' now renamed to >> 'struct virtio_vsock_seq_state'. >> 2) Field 'seqpacket_state' of 'struct virtio_vsock_sock' now >> renamed to 'seq_state'. >> 3) Current message length to process('user_read_seq_len') is >> set to 0 on error or message dequeue completed sucecssfully. >> >> include/linux/virtio_vsock.h | 14 +++ >> include/uapi/linux/virtio_vsock.h | 16 ++++ >> net/vmw_vsock/virtio_transport_common.c | 121 ++++++++++++++++++++++++ >> 3 files changed, 151 insertions(+) >> >> diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h >> index dc636b727179..0e3aa395c07c 100644 >> --- a/include/linux/virtio_vsock.h >> +++ b/include/linux/virtio_vsock.h >> @@ -18,6 +18,12 @@ enum { >> VSOCK_VQ_MAX = 3, >> }; >> >> +struct virtio_vsock_seq_state { >> + u32 user_read_seq_len; >> + u32 user_read_copied; >> + u32 curr_rx_msg_id; >> +}; >> + >> /* Per-socket state (accessed via vsk->trans) */ >> struct virtio_vsock_sock { >> struct vsock_sock *vsk; >> @@ -36,6 +42,8 @@ struct virtio_vsock_sock { >> u32 rx_bytes; >> u32 buf_alloc; >> struct list_head rx_queue; >> + >> + struct virtio_vsock_seq_state seq_state; >> }; >> >> struct virtio_vsock_pkt { >> @@ -80,6 +88,12 @@ virtio_transport_dgram_dequeue(struct vsock_sock *vsk, >> struct msghdr *msg, >> size_t len, int flags); >> >> +int >> +virtio_transport_seqpacket_dequeue(struct vsock_sock *vsk, >> + struct msghdr *msg, >> + int flags, >> + bool *msg_ready, >> + size_t *msg_len); >> s64 virtio_transport_stream_has_data(struct vsock_sock *vsk); >> s64 virtio_transport_stream_has_space(struct vsock_sock *vsk); >> >> diff --git a/include/uapi/linux/virtio_vsock.h b/include/uapi/linux/virtio_vsock.h >> index 1d57ed3d84d2..692f8078cced 100644 >> --- a/include/uapi/linux/virtio_vsock.h >> +++ b/include/uapi/linux/virtio_vsock.h > Maybe we can move the following changes to this file (that should match > the virtio-spec discussed in the separate thread) in a separate patch > with a reference to the spec. > > You can include this in the series before this patch. Ack > >> @@ -63,8 +63,14 @@ struct virtio_vsock_hdr { >> __le32 fwd_cnt; >> } __attribute__((packed)); >> >> +struct virtio_vsock_seq_hdr { >> + __le32 msg_id; >> + __le32 msg_len; >> +} __attribute__((packed)); >> + >> enum virtio_vsock_type { >> VIRTIO_VSOCK_TYPE_STREAM = 1, >> + VIRTIO_VSOCK_TYPE_SEQPACKET = 2, >> }; >> >> enum virtio_vsock_op { >> @@ -83,6 +89,11 @@ enum virtio_vsock_op { >> VIRTIO_VSOCK_OP_CREDIT_UPDATE = 6, >> /* Request the peer to send the credit info to us */ >> VIRTIO_VSOCK_OP_CREDIT_REQUEST = 7, >> + >> + /* Record begin for SOCK_SEQPACKET */ >> + VIRTIO_VSOCK_OP_SEQ_BEGIN = 8, >> + /* Record end for SOCK_SEQPACKET */ >> + VIRTIO_VSOCK_OP_SEQ_END = 9, >> }; >> >> /* VIRTIO_VSOCK_OP_SHUTDOWN flags values */ >> @@ -91,4 +102,9 @@ enum virtio_vsock_shutdown { >> VIRTIO_VSOCK_SHUTDOWN_SEND = 2, >> }; >> >> +/* VIRTIO_VSOCK_OP_RW flags values */ >> +enum virtio_vsock_rw { >> + VIRTIO_VSOCK_RW_EOR = 1, >> +}; >> + >> #endif /* _UAPI_LINUX_VIRTIO_VSOCK_H */ >> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c >> index 833104b71a1c..a8f4326e45e8 100644 >> --- a/net/vmw_vsock/virtio_transport_common.c >> +++ b/net/vmw_vsock/virtio_transport_common.c >> @@ -393,6 +393,114 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk, >> return err; >> } >> >> +static inline void virtio_transport_remove_pkt(struct virtio_vsock_pkt *pkt) >> +{ >> + list_del(&pkt->list); >> + virtio_transport_free_pkt(pkt); >> +} >> + >> +static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk, >> + struct msghdr *msg, >> + bool *msg_ready) >> +{ >> + struct virtio_vsock_sock *vvs = vsk->trans; >> + struct virtio_vsock_pkt *pkt; >> + int err = 0; >> + size_t user_buf_len = msg->msg_iter.count; >> + >> + *msg_ready = false; >> + spin_lock_bh(&vvs->rx_lock); >> + >> + while (!*msg_ready && !list_empty(&vvs->rx_queue) && !err) { >> + pkt = list_first_entry(&vvs->rx_queue, struct virtio_vsock_pkt, list); >> + >> + switch (le16_to_cpu(pkt->hdr.op)) { >> + case VIRTIO_VSOCK_OP_SEQ_BEGIN: { >> + /* Unexpected 'SEQ_BEGIN' during record copy: >> + * Leave receive loop, 'EAGAIN' will restart it from >> + * outer receive loop, packet is still in queue and >> + * counters are cleared. So in next loop enter, >> + * 'SEQ_BEGIN' will be dequeued first. User's iov >> + * iterator will be reset in outer loop. Also >> + * send credit update, because some bytes could be >> + * copied. User will never see unfinished record. >> + */ >> + err = -EAGAIN; >> + break; >> + } >> + case VIRTIO_VSOCK_OP_SEQ_END: { >> + struct virtio_vsock_seq_hdr *seq_hdr; >> + >> + seq_hdr = (struct virtio_vsock_seq_hdr *)pkt->buf; >> + /* First check that whole record is received. */ >> + >> + if (vvs->seq_state.user_read_copied != >> + vvs->seq_state.user_read_seq_len || >> + le32_to_cpu(seq_hdr->msg_id) != >> + vvs->seq_state.curr_rx_msg_id) { >> + /* Tail of current record and head of >> next missed, >> + * so this EOR is from next record. Restart receive. >> + * Current record will be dropped, next headless will >> + * be dropped on next attempt to get record length. >> + */ >> + err = -EAGAIN; >> + } else { >> + /* Success. */ >> + *msg_ready = true; >> + } >> + >> + break; >> + } >> + case VIRTIO_VSOCK_OP_RW: { >> + size_t bytes_to_copy; >> + size_t pkt_len; >> + >> + pkt_len = (size_t)le32_to_cpu(pkt->hdr.len); >> + bytes_to_copy = min(user_buf_len, pkt_len); >> + >> + /* sk_lock is held by caller so no one else can dequeue. >> + * Unlock rx_lock since memcpy_to_msg() may sleep. >> + */ >> + spin_unlock_bh(&vvs->rx_lock); >> + >> + if (memcpy_to_msg(msg, pkt->buf, bytes_to_copy)) { >> + spin_lock_bh(&vvs->rx_lock); >> + err = -EINVAL; >> + break; >> + } >> + >> + spin_lock_bh(&vvs->rx_lock); >> + user_buf_len -= bytes_to_copy; >> + vvs->seq_state.user_read_copied += pkt_len; >> + >> + if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_RW_EOR) >> + msg->msg_flags |= MSG_EOR; >> + break; >> + } >> + default: >> + ; >> + } >> + >> + /* For unexpected 'SEQ_BEGIN', keep such packet in queue, >> + * but drop any other type of packet. >> + */ >> + if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_SEQ_BEGIN) { >> + virtio_transport_dec_rx_pkt(vvs, pkt); >> + virtio_transport_remove_pkt(pkt); >> + } >> + } >> + >> + /* Reset current record length on error or whole message received. */ >> + if (*msg_ready || err) >> + vvs->seq_state.user_read_seq_len = 0; >> + >> + spin_unlock_bh(&vvs->rx_lock); >> + >> + virtio_transport_send_credit_update(vsk); >> + >> + return err; >> +} >> + >> ssize_t >> virtio_transport_stream_dequeue(struct vsock_sock *vsk, >> struct msghdr *msg, >> @@ -405,6 +513,19 @@ virtio_transport_stream_dequeue(struct vsock_sock *vsk, >> } >> EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue); >> >> +int >> +virtio_transport_seqpacket_dequeue(struct vsock_sock *vsk, >> + struct msghdr *msg, >> + int flags, bool *msg_ready, >> + size_t *msg_len) >> +{ >> + if (flags & MSG_PEEK) >> + return -EOPNOTSUPP; >> + > msg_len seems not filled... > > >> + return virtio_transport_seqpacket_do_dequeue(vsk, msg, >> msg_ready); >> +} >> +EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_dequeue); >> + >> int >> virtio_transport_dgram_dequeue(struct vsock_sock *vsk, >> struct msghdr *msg, >> -- >> 2.25.1 >> >