From patchwork Tue Sep 11 22:32:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Cody X-Patchwork-Id: 968739 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 42907v3tvcz9s9h for ; Wed, 12 Sep 2018 08:34:03 +1000 (AEST) Received: from localhost ([::1]:59810 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fzrEO-0005tc-SE for incoming@patchwork.ozlabs.org; Tue, 11 Sep 2018 18:34:00 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36251) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fzrDP-0004Vv-1L for qemu-devel@nongnu.org; Tue, 11 Sep 2018 18:33:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fzrDJ-0006kL-Vr for qemu-devel@nongnu.org; Tue, 11 Sep 2018 18:32:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52390) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fzrDF-0006g1-QQ; Tue, 11 Sep 2018 18:32:50 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 84632307D849; Tue, 11 Sep 2018 22:32:48 +0000 (UTC) Received: from localhost (ovpn-116-183.phx2.redhat.com [10.3.116.183]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 405E060BE0; Tue, 11 Sep 2018 22:32:48 +0000 (UTC) From: Jeff Cody To: qemu-devel@nongnu.org Date: Tue, 11 Sep 2018 18:32:31 -0400 Message-Id: <15b332e5432ad069441f7275a46080f465d789a0.1536704901.git.jcody@redhat.com> In-Reply-To: References: In-Reply-To: References: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Tue, 11 Sep 2018 22:32:48 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v4 2/4] block/rbd: Attempt to parse legacy filenames X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, qemu-block@nongnu.org, libvir-list@redhat.com, jsnow@redhat.com, qemu-stable@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" When we converted rbd to get rid of the older key/value-centric encoding format, we broke compatibility with image files with backing file strings encoded in the old format. This leaves a bit of an ugly conundrum, and a hacky solution. If the initial attempt to parse the "proper" options fails, it assumes that we may have an older key/value encoded filename. Fall back to attempting to parse the filename, and extract the required options from it. If that fails, pass along the original error message. We do not support mixed modern usage alongside legacy keyvalue pair usage. A deprecation warning has been added, although care should be taken when actually deprecating since the impact is not limited to commandline or qapi usage, but also opening existing images. Reviewed-by: Eric Blake Signed-off-by: Jeff Cody --- block/rbd.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 51 insertions(+), 2 deletions(-) diff --git a/block/rbd.c b/block/rbd.c index b199450f9f..5090e4f662 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -678,6 +678,33 @@ static int qemu_rbd_convert_options(QDict *options, BlockdevOptionsRbd **opts, return 0; } +static int qemu_rbd_attempt_legacy_options(QDict *options, + BlockdevOptionsRbd **opts, + char **keypairs) +{ + char *filename; + int r; + + filename = g_strdup(qdict_get_try_str(options, "filename")); + if (!filename) { + return -EINVAL; + } + qdict_del(options, "filename"); + + qemu_rbd_parse_filename(filename, options, NULL); + + /* keypairs freed by caller */ + *keypairs = g_strdup(qdict_get_try_str(options, "=keyvalue-pairs")); + if (*keypairs) { + qdict_del(options, "=keyvalue-pairs"); + } + + r = qemu_rbd_convert_options(options, opts, NULL); + + g_free(filename); + return r; +} + static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { @@ -700,8 +727,30 @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags, r = qemu_rbd_convert_options(options, &opts, &local_err); if (local_err) { - error_propagate(errp, local_err); - goto out; + /* If keypairs are present, that means some options are present in + * the modern option format. Don't attempt to parse legacy option + * formats, as we won't support mixed usage. */ + if (keypairs) { + error_propagate(errp, local_err); + goto out; + } + + /* If the initial attempt to convert and process the options failed, + * we may be attempting to open an image file that has the rbd options + * specified in the older format consisting of all key/value pairs + * encoded in the filename. Go ahead and attempt to parse the + * filename, and see if we can pull out the required options. */ + r = qemu_rbd_attempt_legacy_options(options, &opts, &keypairs); + if (r < 0) { + error_propagate(errp, local_err); + goto out; + } + /* Take care whenever deciding to actually deprecate; once this ability + * is removed, we will not be able to open any images with legacy-styled + * backing image strings. */ + error_report("RBD options encoded in the filename as keyvalue pairs " + "is deprecated. Future versions may cease to parse " + "these options in the future."); } /* Remove the processed options from the QDict (the visitor processes