From patchwork Thu Nov 22 14:06:16 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wei Xu X-Patchwork-Id: 1001821 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4311dc3R2Vz9s8J for ; Fri, 23 Nov 2018 01:13:56 +1100 (AEDT) Received: from localhost ([::1]:46922 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gPpjt-000111-OY for incoming@patchwork.ozlabs.org; Thu, 22 Nov 2018 09:13:53 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36946) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gPph2-00079s-AJ for qemu-devel@nongnu.org; Thu, 22 Nov 2018 09:10:57 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gPpgy-0000Y7-Bh for qemu-devel@nongnu.org; Thu, 22 Nov 2018 09:10:56 -0500 Received: from mx1.redhat.com ([209.132.183.28]:2838) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gPpgy-0000OC-0M for qemu-devel@nongnu.org; Thu, 22 Nov 2018 09:10:52 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id EB0994628E; Thu, 22 Nov 2018 14:10:49 +0000 (UTC) Received: from dell-per430-12.lab.eng.pek2.redhat.com (dell-per430-12.lab.eng.pek2.redhat.com [10.73.196.55]) by smtp.corp.redhat.com (Postfix) with ESMTP id DCE6D84411; Thu, 22 Nov 2018 14:10:26 +0000 (UTC) From: wexu@redhat.com To: jasowang@redhat.com, qemu-devel@nongnu.org Date: Thu, 22 Nov 2018 09:06:16 -0500 Message-Id: <1542895581-10721-12-git-send-email-wexu@redhat.com> In-Reply-To: <1542895581-10721-1-git-send-email-wexu@redhat.com> References: <1542895581-10721-1-git-send-email-wexu@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Thu, 22 Nov 2018 14:10:49 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v1 11/16] virtio-net: fill head desc after done all in a chain X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: maxime.coquelin@redhat.com, jfreimann@redhat.com, wexu@redhat.com, tiwei.bie@intel.com, mst@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Wei Xu With the support of marking a descriptor used/unused in 'flags' field for 1.1, the current way of filling a chained descriptors does not work since driver side may get the wrong 'num_buffer' information in case of the head descriptor has been filled in while the subsequent ones are still in processing in device side. This patch fills the head one after done all the others one. Signed-off-by: Wei Xu --- hw/net/virtio-net.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 385b1a0..2db0e8b 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -1198,6 +1198,8 @@ static ssize_t virtio_net_receive_rcu(NetClientState *nc, const uint8_t *buf, struct virtio_net_hdr_mrg_rxbuf mhdr; unsigned mhdr_cnt = 0; size_t offset, i, guest_offset; + VirtQueueElement head; + int head_len = 0; if (!virtio_net_can_receive(nc)) { return -1; @@ -1275,7 +1277,13 @@ static ssize_t virtio_net_receive_rcu(NetClientState *nc, const uint8_t *buf, } /* signal other side */ - virtqueue_fill(q->rx_vq, elem, total, i++); + if (i == 0) { + head_len = total; + head = *elem; + } else { + virtqueue_fill(q->rx_vq, elem, len, i); + } + i++; g_free(elem); } @@ -1286,6 +1294,7 @@ static ssize_t virtio_net_receive_rcu(NetClientState *nc, const uint8_t *buf, &mhdr.num_buffers, sizeof mhdr.num_buffers); } + virtqueue_fill(q->rx_vq, &head, head_len, 0); virtqueue_flush(q->rx_vq, i); virtio_notify(vdev, q->rx_vq);