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: 10191383 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id F192E601A0 for ; Tue, 30 Jan 2018 06:38:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DB9D028928 for ; Tue, 30 Jan 2018 06:38:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D079428932; Tue, 30 Jan 2018 06:38:01 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 8D51028928 for ; Tue, 30 Jan 2018 06:38:01 +0000 (UTC) Received: from localhost ([::1]:43503 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1egPYO-0002Ny-R2 for patchwork-qemu-devel@patchwork.kernel.org; Tue, 30 Jan 2018 01:38:00 -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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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.