From patchwork Tue Jan 30 06:34:33 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 867407 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=) 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 3zVxWg1n3Sz9s72 for ; Tue, 30 Jan 2018 17:37:35 +1100 (AEDT) Received: from localhost ([::1]:43469 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1egPXx-0001jn-BQ for incoming@patchwork.ozlabs.org; Tue, 30 Jan 2018 01:37:33 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46232) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1egPVM-0000DE-M2 for qemu-devel@nongnu.org; Tue, 30 Jan 2018 01:34:53 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1egPVL-0002hI-Sn for qemu-devel@nongnu.org; Tue, 30 Jan 2018 01:34:52 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58272) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1egPVJ-0002fs-Vd; Tue, 30 Jan 2018 01:34:50 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3C8927EA95; Tue, 30 Jan 2018 06:34:49 +0000 (UTC) Received: from lemon.usersys.redhat.com (ovpn-12-35.pek2.redhat.com [10.72.12.35]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2AFB718AC9; Tue, 30 Jan 2018 06:34:45 +0000 (UTC) From: Fam Zheng To: qemu-devel@nongnu.org Date: Tue, 30 Jan 2018 14:34:33 +0800 Message-Id: <20180130063433.11605-3-famz@redhat.com> In-Reply-To: <20180130063433.11605-1-famz@redhat.com> References: <20180130063433.11605-1-famz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Tue, 30 Jan 2018 06:34:49 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v6 2/2] qemu-img: Document --force-share / -U 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: Kevin Wolf , qemu-block@nongnu.org, kchamart@redhat.com, Max Reitz , stefanha@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Signed-off-by: Fam Zheng Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake --- qemu-img.texi | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/qemu-img.texi b/qemu-img.texi index 60a0e080c6..ec7e2f5d1e 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -86,6 +86,13 @@ exclusive with the @var{-O} parameters. It is currently required to also use the @var{-n} parameter to skip image creation. This restriction may be relaxed in a future release. +@item --force-share (-U) +If specified, @code{qemu-img} will open the image in shared mode, allowing +concurrent writers. For example, this can be used to get the image information +(with 'info' subcommand) when the image is used by a running guest. Note that +this could produce inconsistent results because of concurrent metadata changes, +etc. This option is only allowed when opening images in read-only mode. + @item --backing-chain will enumerate information about backing files in a disk image chain. Refer below for further description.