From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53344) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W6kVE-0003vu-Ij for qemu-devel@nongnu.org; Fri, 24 Jan 2014 12:25:17 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W6kV7-0008JW-TB for qemu-devel@nongnu.org; Fri, 24 Jan 2014 12:25:12 -0500 Received: from mx1.redhat.com ([209.132.183.28]:41850) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W6kV7-0008Gn-Db for qemu-devel@nongnu.org; Fri, 24 Jan 2014 12:25:05 -0500 From: Kevin Wolf Date: Fri, 24 Jan 2014 18:21:45 +0100 Message-Id: <1390584136-24703-63-git-send-email-kwolf@redhat.com> In-Reply-To: <1390584136-24703-1-git-send-email-kwolf@redhat.com> References: <1390584136-24703-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 62/93] block: resize backing image during active layer commit, if needed List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: anthony@codemonkey.ws Cc: kwolf@redhat.com, qemu-devel@nongnu.org From: Jeff Cody If the top image to commit is the active layer, and also larger than the base image, then an I/O error will likely be returned during block-commit. For instance, if we have a base image with a virtual size 10G, and a active layer image of size 20G, then committing the snapshot via 'block-commit' will likely fail. This will automatically attempt to resize the base image, if the active layer image to be committed is larger. Signed-off-by: Jeff Cody Reviewed-by: Eric Blake Reviewed-by: Benoit Canet Signed-off-by: Kevin Wolf --- block/mirror.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/block/mirror.c b/block/mirror.c index 05758e5..2a43334 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -631,11 +631,49 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base, BlockDriverCompletionFunc *cb, void *opaque, Error **errp) { + int64_t length, base_length; + int orig_base_flags; + + orig_base_flags = bdrv_get_flags(base); + if (bdrv_reopen(base, bs->open_flags, errp)) { return; } + + length = bdrv_getlength(bs); + if (length < 0) { + error_setg(errp, "Unable to determine length of %s", bs->filename); + goto error_restore_flags; + } + + base_length = bdrv_getlength(base); + if (base_length < 0) { + error_setg(errp, "Unable to determine length of %s", base->filename); + goto error_restore_flags; + } + + if (length > base_length) { + if (bdrv_truncate(base, length) < 0) { + error_setg(errp, "Top image %s is larger than base image %s, and " + "resize of base image failed", + bs->filename, base->filename); + goto error_restore_flags; + } + } + bdrv_ref(base); mirror_start_job(bs, base, speed, 0, 0, on_error, on_error, cb, opaque, errp, &commit_active_job_driver, false, base); + if (error_is_set(errp)) { + goto error_restore_flags; + } + + return; + +error_restore_flags: + /* ignore error and errp for bdrv_reopen, because we want to propagate + * the original error */ + bdrv_reopen(base, orig_base_flags, NULL); + return; } -- 1.8.1.4