From patchwork Fri Dec 13 07:35:16 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 300923 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 48EF22C00A3 for ; Fri, 13 Dec 2013 18:38:49 +1100 (EST) Received: from localhost ([::1]:40501 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VrNKg-0000SN-PX for incoming@patchwork.ozlabs.org; Fri, 13 Dec 2013 02:38:46 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59899) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VrNIn-00065P-CX for qemu-devel@nongnu.org; Fri, 13 Dec 2013 02:36:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VrNIh-0005ix-80 for qemu-devel@nongnu.org; Fri, 13 Dec 2013 02:36:49 -0500 Received: from mx1.redhat.com ([209.132.183.28]:2354) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VrNIg-0005is-VO for qemu-devel@nongnu.org; Fri, 13 Dec 2013 02:36:43 -0500 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id rBD7aLVw023461 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 13 Dec 2013 02:36:29 -0500 Received: from ad.nay.redhat.com ([10.66.6.190]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id rBD7ZUaL010195; Fri, 13 Dec 2013 02:36:18 -0500 From: Fam Zheng To: qemu-devel@nongnu.org Date: Fri, 13 Dec 2013 15:35:16 +0800 Message-Id: <1386920120-2651-9-git-send-email-famz@redhat.com> In-Reply-To: <1386920120-2651-1-git-send-email-famz@redhat.com> References: <1386920120-2651-1-git-send-email-famz@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com, rjones@redhat.com, armbru@redhat.com, imain@redhat.com, stefanha@redhat.com, pbonzini@redhat.com Subject: [Qemu-devel] [PATCH v8 08/12] block: Parse "backing" option to reference existing BDS 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 Now it's safe to allow reference for backing_hd in the interface. Signed-off-by: Fam Zheng --- block.c | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-) diff --git a/block.c b/block.c index b3993d7..fba7148 100644 --- a/block.c +++ b/block.c @@ -1191,11 +1191,25 @@ int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options, /* If there is a backing file, use it */ if ((flags & BDRV_O_NO_BACKING) == 0) { QDict *backing_options; - - qdict_extract_subqdict(options, &backing_options, "backing."); - ret = bdrv_open_backing_file(bs, backing_options, &local_err); - if (ret < 0) { - goto close_and_fail; + const char *backing_name; + BlockDriverState *backing_hd; + + backing_name = qdict_get_try_str(options, "backing"); + qdict_del(options, "backing"); + if (backing_name) { + backing_hd = bdrv_find(backing_name); + if (!backing_hd) { + error_set(&local_err, QERR_DEVICE_NOT_FOUND, backing_name); + ret = -ENOENT; + goto close_and_fail; + } + bdrv_set_backing_hd(bs, backing_hd); + } else { + qdict_extract_subqdict(options, &backing_options, "backing."); + ret = bdrv_open_backing_file(bs, backing_options, &local_err); + if (ret < 0) { + goto close_and_fail; + } } } @@ -1682,7 +1696,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old) assert(QLIST_EMPTY(&bs_new->dirty_bitmaps)); assert(bs_new->job == NULL); assert(bs_new->dev == NULL); - assert(bdrv_op_blocker_is_empty(bs_new)); assert(bs_new->io_limits_enabled == false); assert(!throttle_have_timer(&bs_new->throttle_state)); @@ -1701,7 +1714,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old) /* Check a few fields that should remain attached to the device */ assert(bs_new->dev == NULL); assert(bs_new->job == NULL); - assert(bdrv_op_blocker_is_empty(bs_new)); assert(bs_new->io_limits_enabled == false); assert(!throttle_have_timer(&bs_new->throttle_state));