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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 98484C31E46 for ; Wed, 12 Jun 2019 22:40:04 +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 6AC3320B7C for ; Wed, 12 Jun 2019 22:40:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6AC3320B7C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:35601 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hbBuV-0000sD-MG for qemu-devel@archiver.kernel.org; Wed, 12 Jun 2019 18:40:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45976) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hbBSc-000872-U1 for qemu-devel@nongnu.org; Wed, 12 Jun 2019 18:11:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hbBSa-00080h-SZ for qemu-devel@nongnu.org; Wed, 12 Jun 2019 18:11:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56590) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hbBSV-0007vY-PY; Wed, 12 Jun 2019 18:11:07 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 37C9930C0DE0; Wed, 12 Jun 2019 22:11:06 +0000 (UTC) Received: from localhost (unknown [10.40.205.72]) by smtp.corp.redhat.com (Postfix) with ESMTPS id BCCBD614C8; Wed, 12 Jun 2019 22:11:05 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Thu, 13 Jun 2019 00:09:45 +0200 Message-Id: <20190612221004.2317-24-mreitz@redhat.com> In-Reply-To: <20190612221004.2317-1-mreitz@redhat.com> References: <20190612221004.2317-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Wed, 12 Jun 2019 22:11:06 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v5 23/42] blockdev: Use CAF in external_snapshot_prepare() 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: Kevin Wolf , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This allows us to differentiate between filters and nodes with COW backing files: Filters cannot be used as overlays at all (for this function). Signed-off-by: Max Reitz --- blockdev.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/blockdev.c b/blockdev.c index b5c0fd3c49..0f0cf0d9ae 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1665,7 +1665,12 @@ static void external_snapshot_prepare(BlkActionSta= te *common, goto out; } =20 - if (state->new_bs->backing !=3D NULL) { + if (state->new_bs->drv->is_filter) { + error_setg(errp, "Filters cannot be used as overlays"); + goto out; + } + + if (bdrv_filtered_cow_child(state->new_bs)) { error_setg(errp, "The overlay already has a backing image"); goto out; } --=20 2.21.0