From patchwork Fri Feb 9 05:29:14 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 10208247 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 9EB47602D8 for ; Fri, 9 Feb 2018 05:30:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 709D129644 for ; Fri, 9 Feb 2018 05:30:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 61F3829646; Fri, 9 Feb 2018 05:30:50 +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 E7F1D29644 for ; Fri, 9 Feb 2018 05:30:49 +0000 (UTC) Received: from localhost ([::1]:37606 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ek1Gq-00062k-7e for patchwork-qemu-devel@patchwork.kernel.org; Fri, 09 Feb 2018 00:30:48 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57509) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ek1Fi-00050M-OL for qemu-devel@nongnu.org; Fri, 09 Feb 2018 00:29:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ek1Fh-0003xw-Qv for qemu-devel@nongnu.org; Fri, 09 Feb 2018 00:29:38 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:38216 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ek1Ff-0003x3-Oz; Fri, 09 Feb 2018 00:29:35 -0500 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5902D407604F; Fri, 9 Feb 2018 05:29:35 +0000 (UTC) Received: from lemon.usersys.redhat.com (ovpn-12-69.pek2.redhat.com [10.72.12.69]) by smtp.corp.redhat.com (Postfix) with ESMTP id BDE0E100839D; Fri, 9 Feb 2018 05:29:32 +0000 (UTC) From: Fam Zheng To: qemu-devel@nongnu.org Date: Fri, 9 Feb 2018 13:29:14 +0800 Message-Id: <20180209052915.12855-3-famz@redhat.com> In-Reply-To: <20180209052915.12855-1-famz@redhat.com> References: <20180209052915.12855-1-famz@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Fri, 09 Feb 2018 05:29:35 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Fri, 09 Feb 2018 05:29:35 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'famz@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v7 2/3] 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 --- qemu-img.texi | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/qemu-img.texi b/qemu-img.texi index 60a0e080c6..8a26400adb 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -86,6 +86,14 @@ 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 +other QEMU processes to open it in write mode. 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.