From patchwork Wed Mar 25 09:36:14 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wen Congyang X-Patchwork-Id: 454331 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)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id E3C55140077 for ; Wed, 25 Mar 2015 20:38:27 +1100 (AEDT) Received: from localhost ([::1]:37101 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yahla-0006Ke-3E for incoming@patchwork.ozlabs.org; Wed, 25 Mar 2015 05:38:26 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40681) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yahh1-0006TC-Qg for qemu-devel@nongnu.org; Wed, 25 Mar 2015 05:33:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yahh0-0007zI-PL for qemu-devel@nongnu.org; Wed, 25 Mar 2015 05:33:43 -0400 Received: from [59.151.112.132] (port=19442 helo=heian.cn.fujitsu.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yahh0-0007w9-Cm; Wed, 25 Mar 2015 05:33:42 -0400 X-IronPort-AV: E=Sophos;i="5.04,848,1406563200"; d="scan'208";a="89293818" Received: from unknown (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 25 Mar 2015 17:29:57 +0800 Received: from G08CNEXCHPEKD02.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id t2P9Wdjr015845; Wed, 25 Mar 2015 17:32:39 +0800 Received: from G08FNSTD140052.g08.fujitsu.local (10.167.226.52) by G08CNEXCHPEKD02.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.181.6; Wed, 25 Mar 2015 17:33:45 +0800 From: Wen Congyang To: qemu devel , Fam Zheng , Max Reitz , Paolo Bonzini Date: Wed, 25 Mar 2015 17:36:14 +0800 Message-ID: <1427276174-9130-14-git-send-email-wency@cn.fujitsu.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1427276174-9130-1-git-send-email-wency@cn.fujitsu.com> References: <1427276174-9130-1-git-send-email-wency@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.52] X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 59.151.112.132 Cc: Kevin Wolf , qemu block , Lai Jiangshan , Jiang Yunhong , Dong Eddie , "Dr. David Alan Gilbert" , Gonglei , Stefan Hajnoczi , Yang Hongyang , zhanghailiang Subject: [Qemu-devel] [RFC PATCH COLO v2 13/13] Don't allow a disk use backing reference target 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 Signed-off-by: Wen Congyang Signed-off-by: zhanghailiang Signed-off-by: Gonglei --- block.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/block.c b/block.c index 3af5ad4..548cafa 100644 --- a/block.c +++ b/block.c @@ -1399,6 +1399,14 @@ static int bdrv_open_backing_reference_file(BlockDriverState *bs, } backing_hd = blk_bs(backing_blk); + /* Don't allow a disk use backing reference target */ + ret = blk_attach_dev(backing_hd->blk, bs); + if (ret < 0) { + error_setg(errp, "backing_hd %s is used by the other device model", + backing_name); + goto free_exit; + } + /* Backing reference itself? */ if (backing_hd == bs || bdrv_find_overlay(backing_hd, bs)) { error_setg(errp, "Backing reference itself"); @@ -2077,6 +2085,7 @@ void bdrv_close(BlockDriverState *bs) if (backing_hd->backing_hd->job) { block_job_cancel(backing_hd->backing_hd->job); } + blk_detach_dev(backing_hd->backing_hd->blk, bs); bdrv_set_backing_hd(backing_hd, NULL); bdrv_unref(backing_hd->backing_hd); }