From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34668) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eGsOa-0007mn-1o for qemu-devel@nongnu.org; Mon, 20 Nov 2017 15:10:21 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eGsOY-0006in-Vj for qemu-devel@nongnu.org; Mon, 20 Nov 2017 15:10:19 -0500 From: Max Reitz Date: Mon, 20 Nov 2017 21:09:40 +0100 Message-Id: <20171120201004.14999-2-mreitz@redhat.com> In-Reply-To: <20171120201004.14999-1-mreitz@redhat.com> References: <20171120201004.14999-1-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v7 for-2.12 01/25] block/mirror: Small absolute-paths simplification List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Max Reitz , Kevin Wolf , Alberto Garcia , Eric Blake , John Snow When invoking drive-mirror in absolute-paths mode, the target's backing BDS is assigned to it in mirror_exit(). The current logic only does so if the target does not have that backing BDS already; but it actually cannot have a backing BDS at all (the BDS is opened with O_NO_BACKING in qmp_drive_mirror()), so just assert that and assign the new backing BDS unconditionally. Signed-off-by: Max Reitz Reviewed-by: Alberto Garcia --- block/mirror.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index 307b6391a8..f995924032 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -523,12 +523,12 @@ static void mirror_exit(BlockJob *job, void *opaque) &error_abort); if (s->backing_mode == MIRROR_SOURCE_BACKING_CHAIN) { BlockDriverState *backing = s->is_none_mode ? src : s->base; - if (backing_bs(target_bs) != backing) { - bdrv_set_backing_hd(target_bs, backing, &local_err); - if (local_err) { - error_report_err(local_err); - data->ret = -EPERM; - } + + assert(!target_bs->backing); + bdrv_set_backing_hd(target_bs, backing, &local_err); + if (local_err) { + error_report_err(local_err); + data->ret = -EPERM; } } -- 2.13.6