From patchwork Thu Aug 4 18:17:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eugenio Perez Martin X-Patchwork-Id: 12936563 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 34342C19F2A for ; Thu, 4 Aug 2022 18:21:54 +0000 (UTC) Received: from localhost ([::1]:56310 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oJfTl-0001DX-9N for qemu-devel@archiver.kernel.org; Thu, 04 Aug 2022 14:21:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60886) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oJfPu-0005yW-QL for qemu-devel@nongnu.org; Thu, 04 Aug 2022 14:17:54 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:60381) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oJfPr-0001Ei-QL for qemu-devel@nongnu.org; Thu, 04 Aug 2022 14:17:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1659637071; 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=ZJjoWNgiO9pSxFfxgEXPumFynQaR4e570fIWsLS9YCg=; b=Nv7dQgo9IBDKRdHrkEQ8Fu3FMnJagx8kXt1iU0gzeHT9aYBMEkaj1AfzNxWg6au++9dZfV joZ1VoY4+CJijJibYJ5fVjfgkVrLDGpaKyahnrbl4wa8mr/CMKTCVApeiC1R6SYbBxsagS 8d0utcHX8jpVrX7JUYq/AC6KuO0ChgY= 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-544-4zXFXU4CMx6tSiYqmq2GQQ-1; Thu, 04 Aug 2022 14:17:47 -0400 X-MC-Unique: 4zXFXU4CMx6tSiYqmq2GQQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7CB6818B53EB; Thu, 4 Aug 2022 18:17:31 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.192.132]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5FFB8492C3B; Thu, 4 Aug 2022 18:17:28 +0000 (UTC) From: =?utf-8?q?Eugenio_P=C3=A9rez?= To: qemu-devel@nongnu.org Cc: Stefano Garzarella , "Gonglei (Arei)" , Cornelia Huck , Liuxiangdong , "Michael S. Tsirkin" , Jason Wang , Gautam Dawar , Laurent Vivier , Eli Cohen , Zhu Lingshan , Cindy Lu , Stefan Hajnoczi , Parav Pandit , Paolo Bonzini , Harpreet Singh Anand , Eric Blake , Markus Armbruster Subject: [PATCH v6 01/12] vhost: stop transfer elem ownership in vhost_handle_guest_kick Date: Thu, 4 Aug 2022 20:17:11 +0200 Message-Id: <20220804181722.701067-2-eperezma@redhat.com> In-Reply-To: <20220804181722.701067-1-eperezma@redhat.com> References: <20220804181722.701067-1-eperezma@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 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: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 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_NONE=-0.0001, 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" It was easier to allow vhost_svq_add to handle the memory. Now that we will allow qemu to add elements to a SVQ without the guest's knowledge, it's better to handle it in the caller. Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-shadow-virtqueue.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index e4956728dd..ffd2b2c972 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -233,9 +233,6 @@ static void vhost_svq_kick(VhostShadowVirtqueue *svq) /** * Add an element to a SVQ. * - * The caller must check that there is enough slots for the new element. It - * takes ownership of the element: In case of failure not ENOSPC, it is free. - * * Return -EINVAL if element is invalid, -ENOSPC if dev queue is full */ int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg, @@ -252,7 +249,6 @@ int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg, ok = vhost_svq_add_split(svq, out_sg, out_num, in_sg, in_num, &qemu_head); if (unlikely(!ok)) { - g_free(elem); return -EINVAL; } @@ -293,7 +289,7 @@ static void vhost_handle_guest_kick(VhostShadowVirtqueue *svq) virtio_queue_set_notification(svq->vq, false); while (true) { - VirtQueueElement *elem; + g_autofree VirtQueueElement *elem; int r; if (svq->next_guest_avail_elem) { @@ -324,12 +320,14 @@ static void vhost_handle_guest_kick(VhostShadowVirtqueue *svq) * queue the current guest descriptor and ignore kicks * until some elements are used. */ - svq->next_guest_avail_elem = elem; + svq->next_guest_avail_elem = g_steal_pointer(&elem); } /* VQ is full or broken, just return and ignore kicks */ return; } + /* elem belongs to SVQ or external caller now */ + elem = NULL; } virtio_queue_set_notification(svq->vq, true);