From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3068EC433DF for ; Thu, 14 May 2020 14:25:35 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EBD86206A5 for ; Thu, 14 May 2020 14:25:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bPzzTm6P" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EBD86206A5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52958 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jZEnm-00007A-0z for qemu-devel@archiver.kernel.org; Thu, 14 May 2020 10:25:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39280) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jZEiw-0000S6-BC for qemu-devel@nongnu.org; Thu, 14 May 2020 10:20:34 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:26890 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jZEiu-00058G-Qx for qemu-devel@nongnu.org; Thu, 14 May 2020 10:20:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1589466031; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ojG+ubwH30+tQj377iUQceXxuhYLTEPDXDGrFOO5g30=; b=bPzzTm6P3D8ufJmnblA0r6xCBPYdyuDOD538hhCEBaVxHhUv41n5+VGRmujMBJEijWg3LY 65u2cOXLk12F1+th5UmVTAUN6Hy/1m5dkLsllPFun1rQoBvOsyDsRUXgPOQsZ2XngE9n1h KHoFdv402Zq3dfOI2G+tu4ca3LruCJ8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-326-Sq2qO54-MeeiQNLqBkzFKA-1; Thu, 14 May 2020 10:20:29 -0400 X-MC-Unique: Sq2qO54-MeeiQNLqBkzFKA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6CBD2A0BDC; Thu, 14 May 2020 14:20:28 +0000 (UTC) Received: from [10.3.116.145] (ovpn-116-145.phx2.redhat.com [10.3.116.145]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7CAF95D714; Thu, 14 May 2020 14:20:27 +0000 (UTC) Subject: Re: [PATCH v4 6/9] qemu-img: Add bitmap sub-command To: Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org References: <20200513011648.166876-1-eblake@redhat.com> <20200513011648.166876-7-eblake@redhat.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: <0542a587-424c-a596-1778-e7aaf494298c@redhat.com> Date: Thu, 14 May 2020 09:20:24 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=205.139.110.61; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/13 22:25:42 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, nsoffer@redhat.com, qemu-block@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 5/14/20 1:45 AM, Vladimir Sementsov-Ogievskiy wrote: > 13.05.2020 04:16, Eric Blake wrote: >> Include actions for --add, --remove, --clear, --enable, --disable, and >> --merge (note that --clear is a bit of fluff, because the same can be >> accomplished by removing a bitmap and then adding a new one in its >> place, but it matches what QMP commands exist).  Listing is omitted, >> because it does not require a bitmap name and because it was already >> possible with 'qemu-img info'.  A single command line can play one or >> more bitmap commands in sequence on the same bitmap name (although all >> added bitmaps share the same granularity, and and all merged bitmaps >> come from the same source file).  Merge defaults to other bitmaps in >> the primary image, but can also be told to merge bitmaps from a >> distinct image. >> > > I'm sorry for asking it only now on v4.. But still. Why do we need it? Ease of use. > We can instead run qemu binary (or even new qemu-storage-daemon) and > just use existing qmp commands. Is there a real benefit in developing > qemu-img, maintaining two interfaces for the same thing? If it makes someone's life easier, and is not hard to maintain, then yes. A command line interface that calls into QMP is not hard to maintain. And _I_ certainly found it easier to write iotests with this patch in place, so it already has at least one client. > Of-course, just > run qmp commands from terminal is a lot less comfortable than just a > qemu img command.. But may be we need some wrapper, which make it simple > to run one qmp command on an image? > > It's simple to make a python wrapper working like > > qemu-qmp block-dirty-bitmap-add '{node: self, name: bitmap0, persistent: > true}' /path/to/x.qcow2 This _IS_ such a wrapper. The whole point of this patch is that it is now simpler to run one (or more) QMP command on an offline image from the command line. Just because I wrote it in C instead of python, and attached it to an existing tool instead of writing a new tool, doesn't change the fact that it is just a wrapper around the existing QMP commands. -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org