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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F9A7C433F5 for ; Fri, 1 Oct 2021 07:24:02 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id DAE23619F5 for ; Fri, 1 Oct 2021 07:24:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org DAE23619F5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:49148 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mWCtk-000073-T3 for qemu-devel@archiver.kernel.org; Fri, 01 Oct 2021 03:24:00 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36434) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mWChH-0000N2-Fk for qemu-devel@nongnu.org; Fri, 01 Oct 2021 03:11:09 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:45116) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mWChF-00049a-8J for qemu-devel@nongnu.org; Fri, 01 Oct 2021 03:11:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1633072264; 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=4FMWHKJqRbXnJMl22nuaafL4UiVJzbsZAYB/Jd90dFw=; b=BUkmQ9xeBlkfNKaPGPMgtqa46DCxI3ZxGluDUT2nci42PCUxvVvP7m/OH1V+IP78KpTgH+ +uAY9vtkxtFUkl5VW3kCUjcrpveUeZYJU0X0ab6zDCJEsDhx9yatYcAhCG/UXGrRiDV0M8 9qDHWra0um8AzhyDe/zWXSi72CQcasE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-504-VVFSyDVeNS2wi_5T09gClA-1; Fri, 01 Oct 2021 03:11:03 -0400 X-MC-Unique: VVFSyDVeNS2wi_5T09gClA-1 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3872D10151E0; Fri, 1 Oct 2021 07:11:02 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.193.2]) by smtp.corp.redhat.com (Postfix) with ESMTP id 34B1053E08; Fri, 1 Oct 2021 07:10:53 +0000 (UTC) From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= To: qemu-devel@nongnu.org Subject: [RFC PATCH v4 11/20] vhost: Route host->guest notification through shadow virtqueue Date: Fri, 1 Oct 2021 09:05:54 +0200 Message-Id: <20211001070603.307037-12-eperezma@redhat.com> In-Reply-To: <20211001070603.307037-1-eperezma@redhat.com> References: <20211001070603.307037-1-eperezma@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eperezma@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 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_LOW=-0.7, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Parav Pandit , Juan Quintela , Jason Wang , "Michael S. Tsirkin" , Markus Armbruster , virtualization@lists.linux-foundation.org, Harpreet Singh Anand , Xiao W Wang , Stefan Hajnoczi , Eli Cohen , Eric Blake , Michael Lilja , Stefano Garzarella Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This will make qemu aware of the device used buffers, allowing it to write the guest memory with its contents if needed. Since the use of vhost_virtqueue_start can unmasks and discard call events, vhost_virtqueue_start should be modified in one of these ways: * Split in two: One of them uses all logic to start a queue with no side effects for the guest, and another one tha actually assumes that the guest has just started the device. Vdpa should use just the former. * Actually store and check if the guest notifier is masked, and do it conditionally. * Left as it is, and duplicate all the logic in vhost-vdpa. Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-shadow-virtqueue.c | 19 +++++++++++++++ hw/virtio/vhost-vdpa.c | 38 +++++++++++++++++++++++++++++- 2 files changed, 56 insertions(+), 1 deletion(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index 21dc99ab5d..3fe129cf63 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -53,6 +53,22 @@ static void vhost_handle_guest_kick(EventNotifier *n) event_notifier_set(&svq->kick_notifier); } +/* Forward vhost notifications */ +static void vhost_svq_handle_call_no_test(EventNotifier *n) +{ + VhostShadowVirtqueue *svq = container_of(n, VhostShadowVirtqueue, + call_notifier); + + event_notifier_set(&svq->guest_call_notifier); +} + +static void vhost_svq_handle_call(EventNotifier *n) +{ + if (likely(event_notifier_test_and_clear(n))) { + vhost_svq_handle_call_no_test(n); + } +} + /* * Obtain the SVQ call notifier, where vhost device notifies SVQ that there * exists pending used buffers. @@ -180,6 +196,8 @@ VhostShadowVirtqueue *vhost_svq_new(struct vhost_dev *dev, int idx) } svq->vq = virtio_get_queue(dev->vdev, vq_idx); + event_notifier_set_handler(&svq->call_notifier, + vhost_svq_handle_call); return g_steal_pointer(&svq); err_init_call_notifier: @@ -195,6 +213,7 @@ err_init_kick_notifier: void vhost_svq_free(VhostShadowVirtqueue *vq) { event_notifier_cleanup(&vq->kick_notifier); + event_notifier_set_handler(&vq->call_notifier, NULL); event_notifier_cleanup(&vq->call_notifier); g_free(vq); } diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c index bc34de2439..6c5f4c98b8 100644 --- a/hw/virtio/vhost-vdpa.c +++ b/hw/virtio/vhost-vdpa.c @@ -712,13 +712,40 @@ static bool vhost_vdpa_svq_start_vq(struct vhost_dev *dev, unsigned idx) { struct vhost_vdpa *v = dev->opaque; VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, idx); - return vhost_svq_start(dev, idx, svq); + EventNotifier *vhost_call_notifier = vhost_svq_get_svq_call_notifier(svq); + struct vhost_vring_file vhost_call_file = { + .index = idx + dev->vq_index, + .fd = event_notifier_get_fd(vhost_call_notifier), + }; + int r; + bool b; + + /* Set shadow vq -> guest notifier */ + assert(v->call_fd[idx]); + vhost_svq_set_guest_call_notifier(svq, v->call_fd[idx]); + + b = vhost_svq_start(dev, idx, svq); + if (unlikely(!b)) { + return false; + } + + /* Set device -> SVQ notifier */ + r = vhost_vdpa_set_vring_dev_call(dev, &vhost_call_file); + if (unlikely(r)) { + error_report("vhost_vdpa_set_vring_call for shadow vq failed"); + return false; + } + + /* Check for pending calls */ + event_notifier_set(vhost_call_notifier); + return true; } static unsigned vhost_vdpa_enable_svq(struct vhost_vdpa *v, bool enable) { struct vhost_dev *hdev = v->dev; unsigned n; + int r; if (enable == v->shadow_vqs_enabled) { return hdev->nvqs; @@ -752,9 +779,18 @@ static unsigned vhost_vdpa_enable_svq(struct vhost_vdpa *v, bool enable) if (!enable) { /* Disable all queues or clean up failed start */ for (n = 0; n < v->shadow_vqs->len; ++n) { + struct vhost_vring_file file = { + .index = vhost_vdpa_get_vq_index(hdev, n), + .fd = v->call_fd[n], + }; + + r = vhost_vdpa_set_vring_call(hdev, &file); + assert(r == 0); + unsigned vq_idx = vhost_vdpa_get_vq_index(hdev, n); VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, n); vhost_svq_stop(hdev, n, svq); + /* TODO: This can unmask or override call fd! */ vhost_virtqueue_start(hdev, hdev->vdev, &hdev->vqs[n], vq_idx); } -- 2.27.0