From patchwork Wed Jun 3 20:13:37 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 480146 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 9728F1401F6 for ; Thu, 4 Jun 2015 06:18:37 +1000 (AEST) Received: from localhost ([::1]:37828 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z0F7T-00020M-NH for incoming@patchwork.ozlabs.org; Wed, 03 Jun 2015 16:18:35 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43203) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z0F3E-0002eX-1c for qemu-devel@nongnu.org; Wed, 03 Jun 2015 16:14:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z0F3C-0008LV-Lq for qemu-devel@nongnu.org; Wed, 03 Jun 2015 16:14:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43197) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z0F38-0008Gr-2y; Wed, 03 Jun 2015 16:14:06 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id C888EB7A65; Wed, 3 Jun 2015 20:14:05 +0000 (UTC) Received: from localhost (ovpn-116-32.ams2.redhat.com [10.36.116.32]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t53KE3cH003577 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 3 Jun 2015 16:14:04 -0400 From: Max Reitz To: qemu-block@nongnu.org Date: Wed, 3 Jun 2015 22:13:37 +0200 Message-Id: <1433362419-15033-9-git-send-email-mreitz@redhat.com> In-Reply-To: <1433362419-15033-1-git-send-email-mreitz@redhat.com> References: <1433362419-15033-1-git-send-email-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: Kevin Wolf , qemu-devel@nongnu.org, Stefan Hajnoczi , Max Reitz Subject: [Qemu-devel] [PATCH v8 08/10] qcow2: Invoke refcount order amendment function 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 Make use of qcow2_change_refcount_order() to support changing the refcount order with qemu-img amend. Signed-off-by: Max Reitz Reviewed-by: Eric Blake --- block/qcow2.c | 44 +++++++++++++++++++++++++++++++++++--------- 1 file changed, 35 insertions(+), 9 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index 62a6cb2..9645663 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2632,13 +2632,7 @@ static int qcow2_downgrade(BlockDriverState *bs, int target_version, } if (s->refcount_order != 4) { - /* we would have to convert the image to a refcount_order == 4 image - * here; however, since qemu (at the time of writing this) does not - * support anything different than 4 anyway, there is no point in doing - * so right now; however, we should error out (if qemu supports this in - * the future and this code has not been adapted) */ - error_report("qcow2_downgrade: Image refcount orders other than 4 are " - "currently not supported."); + error_report("compat=0.10 requires refcount_bits=16"); return -ENOTSUP; } @@ -2686,6 +2680,7 @@ typedef enum Qcow2AmendOperation { * invocation from an operation change */ QCOW2_NO_OPERATION = 0, + QCOW2_CHANGING_REFCOUNT_ORDER, QCOW2_DOWNGRADING, } Qcow2AmendOperation; @@ -2761,6 +2756,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, const char *compat = NULL; uint64_t cluster_size = s->cluster_size; bool encrypt; + int refcount_bits = s->refcount_bits; int ret; QemuOptDesc *desc = opts->list->desc; Qcow2AmendHelperCBInfo helper_cb_info; @@ -2811,8 +2807,16 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, lazy_refcounts = qemu_opt_get_bool(opts, BLOCK_OPT_LAZY_REFCOUNTS, lazy_refcounts); } else if (!strcmp(desc->name, BLOCK_OPT_REFCOUNT_BITS)) { - error_report("Cannot change refcount entry width"); - return -ENOTSUP; + refcount_bits = qemu_opt_get_number(opts, BLOCK_OPT_REFCOUNT_BITS, + refcount_bits); + + if (refcount_bits <= 0 || refcount_bits > 64 || + !is_power_of_2(refcount_bits)) + { + error_report("Refcount width must be a power of two and may " + "not exceed 64 bits"); + return -EINVAL; + } } else { /* if this point is reached, this probably means a new option was * added without having it covered here */ @@ -2826,6 +2830,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, .original_status_cb = status_cb, .original_cb_opaque = cb_opaque, .total_operations = (new_version < old_version) + + (s->refcount_bits != refcount_bits) }; /* Upgrade first (some features may require compat=1.1) */ @@ -2838,6 +2843,27 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, } } + if (s->refcount_bits != refcount_bits) { + int refcount_order = ctz32(refcount_bits); + Error *local_error = NULL; + + if (new_version < 3 && refcount_bits != 16) { + error_report("Different refcount widths than 16 bits require " + "compatibility level 1.1 or above (use compat=1.1 or " + "greater)"); + return -EINVAL; + } + + helper_cb_info.current_operation = QCOW2_CHANGING_REFCOUNT_ORDER; + ret = qcow2_change_refcount_order(bs, refcount_order, + &qcow2_amend_helper_cb, + &helper_cb_info, &local_error); + if (ret < 0) { + qerror_report_err(local_error); + return ret; + } + } + if (backing_file || backing_format) { ret = qcow2_change_backing_file(bs, backing_file ?: s->image_backing_file,