From patchwork Fri Aug 9 16:13:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 1144819 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com 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 ozlabs.org (Postfix) with ESMTPS id 464r9r2mxlz9sNF for ; Sat, 10 Aug 2019 02:22:24 +1000 (AEST) Received: from localhost ([::1]:60947 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hw7eo-00025l-Fl for incoming@patchwork.ozlabs.org; Fri, 09 Aug 2019 12:22:22 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:57345) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hw7Xl-0002VM-OR for qemu-devel@nongnu.org; Fri, 09 Aug 2019 12:15:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hw7Xk-0004LH-SX for qemu-devel@nongnu.org; Fri, 09 Aug 2019 12:15:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59044) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hw7Xi-0004JH-RS; Fri, 09 Aug 2019 12:15:02 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1FC423090FD9; Fri, 9 Aug 2019 16:15:02 +0000 (UTC) Received: from localhost (unknown [10.40.205.179]) by smtp.corp.redhat.com (Postfix) with ESMTPS id ABFDF7E44; Fri, 9 Aug 2019 16:15:01 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Fri, 9 Aug 2019 18:13:48 +0200 Message-Id: <20190809161407.11920-24-mreitz@redhat.com> In-Reply-To: <20190809161407.11920-1-mreitz@redhat.com> References: <20190809161407.11920-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.43]); Fri, 09 Aug 2019 16:15:02 +0000 (UTC) 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 v6 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+incoming=patchwork.ozlabs.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 Reviewed-by: Vladimir Sementsov-Ogievskiy --- blockdev.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/blockdev.c b/blockdev.c index 29c6c6044a..c540802127 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1664,7 +1664,12 @@ static void external_snapshot_prepare(BlkActionState *common, goto out; } - if (state->new_bs->backing != 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; }