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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3B536C636CC for ; Wed, 15 Feb 2023 17:40:00 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pSLkb-0007JD-5v; Wed, 15 Feb 2023 12:39:25 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pSLkZ-0007GP-2f for qemu-devel@nongnu.org; Wed, 15 Feb 2023 12:39:23 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pSLkX-0005ob-Lr for qemu-devel@nongnu.org; Wed, 15 Feb 2023 12:39:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1676482761; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=mkrwBd+ANgFYZFwnQWbbclPSysFfKRnQi/JE7ffnhCM=; b=bcT9c7Ac9zOFarLHyIqGWxeyjDJ/4dBETfoWDVsEVUmCFg9eecCiEd2JFyCsHXDlIPzo7X hSUdOYXWhmffjE4O7pEkqg6KNRGqBu99pUrmd8SKfzqA8mDlV2MwtxjfCfglzXXbijUo0z FpEtw4vnZrKaEy9MVXMNqqAqXxRguKg= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-528-CoKGl6kMMBiakFMLrb6roQ-1; Wed, 15 Feb 2023 12:39:17 -0500 X-MC-Unique: CoKGl6kMMBiakFMLrb6roQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2BAEA3C0DDD6; Wed, 15 Feb 2023 17:39:17 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.192.155]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7A6CA140EBF4; Wed, 15 Feb 2023 17:39:13 +0000 (UTC) From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= To: qemu-devel@nongnu.org Cc: Cindy Lu , Shannon Nelson , longpeng2@huawei.com, virtualization@lists.linux-foundation.org, Harpreet Singh Anand , si-wei.liu@oracle.com, Stefan Hajnoczi , Eli Cohen , "Michael S. Tsirkin" , Gautam Dawar , Laurent Vivier , Liuxiangdong , alvaro.karsz@solid-run.com, Parav Pandit , Stefano Garzarella , Jason Wang , Zhu Lingshan , "Gonglei (Arei)" , Lei Yang Subject: [PATCH v3 06/14] vdpa: rewind at get_base, not set_base Date: Wed, 15 Feb 2023 18:38:42 +0100 Message-Id: <20230215173850.298832-7-eperezma@redhat.com> In-Reply-To: <20230215173850.298832-1-eperezma@redhat.com> References: <20230215173850.298832-1-eperezma@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.133.124; envelope-from=eperezma@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org At this moment it is only possible to migrate to a vdpa device running with x-svq=on. As a protective measure, the rewind of the inflight descriptors was done at the destination. That way if the source sent a virtqueue with inuse descriptors they are always discarded. Since this series allows to migrate also to passthrough devices with no SVQ, the right thing to do is to rewind at the source so the base of vrings are correct. Support for inflight descriptors may be added in the future. Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-vdpa.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c index a5cf2e7069..d253e9dc0e 100644 --- a/hw/virtio/vhost-vdpa.c +++ b/hw/virtio/vhost-vdpa.c @@ -1212,18 +1212,7 @@ static int vhost_vdpa_set_vring_base(struct vhost_dev *dev, struct vhost_vring_state *ring) { struct vhost_vdpa *v = dev->opaque; - VirtQueue *vq = virtio_get_queue(dev->vdev, ring->index); - /* - * vhost-vdpa devices does not support in-flight requests. Set all of them - * as available. - * - * TODO: This is ok for networking, but other kinds of devices might - * have problems with these retransmissions. - */ - while (virtqueue_rewind(vq, 1)) { - continue; - } if (v->shadow_vqs_enabled) { /* * Device vring base was set at device start. SVQ base is handled by @@ -1242,6 +1231,19 @@ static int vhost_vdpa_get_vring_base(struct vhost_dev *dev, int ret; if (v->shadow_vqs_enabled) { + VirtQueue *vq = virtio_get_queue(dev->vdev, ring->index); + + /* + * vhost-vdpa devices does not support in-flight requests. Set all of + * them as available. + * + * TODO: This is ok for networking, but other kinds of devices might + * have problems with these retransmissions. + */ + while (virtqueue_rewind(vq, 1)) { + continue; + } + ring->num = virtio_queue_get_last_avail_idx(dev->vdev, ring->index); return 0; } -- 2.31.1