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 9206AC43334 for ; Thu, 14 Jul 2022 16:42:31 +0000 (UTC) Received: from localhost ([::1]:53332 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oC1v4-0006YJ-OG for qemu-devel@archiver.kernel.org; Thu, 14 Jul 2022 12:42:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36810) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oC1lN-0007eU-Mp for qemu-devel@nongnu.org; Thu, 14 Jul 2022 12:32:29 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:29763) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oC1lM-0003MJ-23 for qemu-devel@nongnu.org; Thu, 14 Jul 2022 12:32:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1657816347; 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=73J69Cux+akPnYx7ikpoE0drb0oq16Z9xxlaorXLPYA=; b=Xg+q2ZVXNgiElfnbptCNfy0aq1SdEKYZ1e6e20WuQqw1ihuFFO2OZsvcQA3KMXliUmcXW0 rpPeuTxJYP8hepbtIsJYiMvTQU3+Y4HHGQOEAFNPiz/uSmUsGSq+7ZUIsYcXMVs2Xbmu6o qZndVUKHePp+FgwbAvZDt9QmWDc2Wc0= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-61-AVzuLWBcPvevXUyjOhiI8g-1; Thu, 14 Jul 2022 12:32:24 -0400 X-MC-Unique: AVzuLWBcPvevXUyjOhiI8g-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id CCF21185A7B2; Thu, 14 Jul 2022 16:32:23 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.192.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0451C1121314; Thu, 14 Jul 2022 16:32:20 +0000 (UTC) From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= To: qemu-devel@nongnu.org Cc: Gautam Dawar , Paolo Bonzini , "Michael S. Tsirkin" , Stefano Garzarella , Eric Blake , Zhu Lingshan , Stefan Hajnoczi , Markus Armbruster , Cornelia Huck , Parav Pandit , Laurent Vivier , Liuxiangdong , Eli Cohen , Cindy Lu , Harpreet Singh Anand , Jason Wang , "Gonglei (Arei)" Subject: [PATCH v2 09/19] vhost: Track number of descs in SVQElement Date: Thu, 14 Jul 2022 18:31:40 +0200 Message-Id: <20220714163150.2536327-10-eperezma@redhat.com> In-Reply-To: <20220714163150.2536327-1-eperezma@redhat.com> References: <20220714163150.2536327-1-eperezma@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 Received-SPF: pass client-ip=170.10.129.124; envelope-from=eperezma@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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" Since CVQ will be able to modify elements, the number of descriptors in the guest may not match with the number of descriptors exposed. Track separately. Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-shadow-virtqueue.h | 6 ++++++ hw/virtio/vhost-shadow-virtqueue.c | 10 +++++----- 2 files changed, 11 insertions(+), 5 deletions(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h index f35d4b8f90..143c86a568 100644 --- a/hw/virtio/vhost-shadow-virtqueue.h +++ b/hw/virtio/vhost-shadow-virtqueue.h @@ -17,6 +17,12 @@ typedef struct SVQElement { VirtQueueElement elem; + + /* + * Number of descriptors exposed to the device. May or may not match + * guest's + */ + unsigned int ndescs; } SVQElement; /* Shadow virtqueue to relay notifications */ diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index 442ca3cbd3..3b112c4ec8 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -243,10 +243,10 @@ static int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg, size_t in_num, SVQElement *svq_elem) { unsigned qemu_head; - unsigned ndescs = in_num + out_num; + svq_elem->ndescs = in_num + out_num; bool ok; - if (unlikely(ndescs > vhost_svq_available_slots(svq))) { + if (unlikely(svq_elem->ndescs > vhost_svq_available_slots(svq))) { return -ENOSPC; } @@ -393,7 +393,7 @@ static SVQElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq, SVQElement *elem; const vring_used_t *used = svq->vring.used; vring_used_elem_t used_elem; - uint16_t last_used, last_used_chain, num; + uint16_t last_used, last_used_chain; if (!vhost_svq_more_used(svq)) { return NULL; @@ -420,8 +420,8 @@ static SVQElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq, } elem = svq->ring_id_maps[used_elem.id]; - num = elem->elem.in_num + elem->elem.out_num; - last_used_chain = vhost_svq_last_desc_of_chain(svq, num, used_elem.id); + last_used_chain = vhost_svq_last_desc_of_chain(svq, elem->ndescs, + used_elem.id); svq->desc_next[last_used_chain] = svq->free_head; svq->free_head = used_elem.id; -- 2.31.1