From patchwork Sun Sep 22 12:05:06 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 276972 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id DF59E2C0079 for ; Sun, 22 Sep 2013 22:06:01 +1000 (EST) Received: from localhost ([::1]:35098 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VNiQJ-0004i7-KA for incoming@patchwork.ozlabs.org; Sun, 22 Sep 2013 08:05:59 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51599) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VNiPl-0004ev-9t for qemu-devel@nongnu.org; Sun, 22 Sep 2013 08:05:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VNiPZ-0006DA-Ip for qemu-devel@nongnu.org; Sun, 22 Sep 2013 08:05:25 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12197) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VNiPZ-0006D2-9K for qemu-devel@nongnu.org; Sun, 22 Sep 2013 08:05:13 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r8MC5Cpf019802 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Sun, 22 Sep 2013 08:05:12 -0400 Received: from T430s.nay.redhat.com ([10.66.6.118]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r8MC58jL006514; Sun, 22 Sep 2013 08:05:11 -0400 From: Fam Zheng To: qemu-devel@nongnu.org Date: Sun, 22 Sep 2013 20:05:06 +0800 Message-Id: <1379851507-17921-2-git-send-email-famz@redhat.com> In-Reply-To: <1379851507-17921-1-git-send-email-famz@redhat.com> References: <1379851507-17921-1-git-send-email-famz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com, stefanha@redhat.com Subject: [Qemu-devel] [PATCH 1/2] block: fix backing file overriding X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Providing backing.file.filename doesn't override backing file as expected: $ x86_64-softmmu/qemu-system-x86_64 -drive \ file=/tmp/child.qcow2,backing.file.filename=/tmp/fake.qcow2 qemu-system-x86_64: -drive \ file=/tmp/child.qcow2,backing.file.filename=/tmp/fake.qcow2: could not open disk image /tmp/child.qcow2: Can't specify 'file' and 'filename' options at the same time With $ qemu-img info /tmp/child.qcow2 image: /tmp/child.qcow2 file format: qcow2 virtual size: 1.0G (1073741824 bytes) disk size: 196K cluster_size: 65536 backing file: /tmp/fake.qcow2 This fixes it by calling bdrv_get_full_backing_filename only if backing.file.filename is not provided. Also save the backing file name to bs->backing_file so the information is correct with HMP "info block". Signed-off-by: Fam Zheng --- block.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index e176c6f..a2ea39a 100644 --- a/block.c +++ b/block.c @@ -978,11 +978,12 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) { QDECREF(options); return 0; + } else { + bdrv_get_full_backing_filename(bs, backing_filename, + sizeof(backing_filename)); } bs->backing_hd = bdrv_new(""); - bdrv_get_full_backing_filename(bs, backing_filename, - sizeof(backing_filename)); if (bs->backing_format[0] != '\0') { back_drv = bdrv_find_format(bs->backing_format); @@ -994,6 +995,8 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) ret = bdrv_open(bs->backing_hd, *backing_filename ? backing_filename : NULL, options, back_flags, back_drv, &local_err); + pstrcpy(bs->backing_file, sizeof(bs->backing_file), + bs->backing_hd->file->filename); if (ret < 0) { bdrv_unref(bs->backing_hd); bs->backing_hd = NULL;