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=-5.2 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, 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 7B144C388F7 for ; Thu, 22 Oct 2020 21:47:28 +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 9A273223BF for ; Thu, 22 Oct 2020 21:47:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="FoUK/Dgr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A273223BF 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]:32922 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kViQg-0005Hn-I0 for qemu-devel@archiver.kernel.org; Thu, 22 Oct 2020 17:47:26 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36182) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kViP0-0004kK-BD for qemu-devel@nongnu.org; Thu, 22 Oct 2020 17:45:42 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:46983) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kViOy-0002bm-2f for qemu-devel@nongnu.org; Thu, 22 Oct 2020 17:45:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1603403137; 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=N9KaKIcT66VziAHts4yZi7YuDzJxEZu9u5eiJ6rv7W4=; b=FoUK/DgraDDE9+CCb4VLBEW2BFSGQs7m1dNgzbS0YDyof9HT/T5OO15o1yzlo1SM8j2Vsc F6gZ03z6pM+P0Ov/3+egUlSk8hdjtkiV5PGtNdhH4nID1gN2IMcz6i1drJ6amlz2jQV54i 5zKpXHcoQsMRA6KNuU6jjeTSYHadPHk= 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-554-vY-0baQDMW2a8xTvIN7XTw-1; Thu, 22 Oct 2020 17:45:26 -0400 X-MC-Unique: vY-0baQDMW2a8xTvIN7XTw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4DAAC1009E21; Thu, 22 Oct 2020 21:45:25 +0000 (UTC) Received: from [10.3.114.232] (ovpn-114-232.phx2.redhat.com [10.3.114.232]) by smtp.corp.redhat.com (Postfix) with ESMTPS id ACE9D6EF48; Thu, 22 Oct 2020 21:45:21 +0000 (UTC) Subject: Re: [PATCH v4 2/7] nbd: Add new qemu:allocation-depth metadata context To: Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org References: <20201009215533.1194742-1-eblake@redhat.com> <20201009215533.1194742-3-eblake@redhat.com> <85c7c5bf-a6cd-77d0-3dba-3e0df0e9570d@virtuozzo.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: <5c416fc3-2f3f-047b-7248-562b9ffb43c1@redhat.com> Date: Thu, 22 Oct 2020 16:45:21 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.3.1 MIME-Version: 1.0 In-Reply-To: <85c7c5bf-a6cd-77d0-3dba-3e0df0e9570d@virtuozzo.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/22 08:09:01 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 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, NICE_REPLY_A=-0.107, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no 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, qemu-block@nongnu.org, rjones@redhat.com, stefanha@redhat.com, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 10/14/20 6:52 AM, Vladimir Sementsov-Ogievskiy wrote: >>   docs/interop/nbd.txt | 27 ++++++++++--- > > [..] > >> +In the allocation depth context, bits 0 and 1 form a tri-state value: >> + >> +    bits 0-1: 00: NBD_STATE_DEPTH_UNALLOC, the extent is unallocated >> +              01: NBD_STATE_DEPTH_LOCAL, the extent is allocated in the >> +                  top level of the image > > Hmm. I always thought that "image" == file, so backing chain is a chain > of images, > not a several levels of one image. If it is so, than it should be "the > top level image". > And "levels of the image" may designate internal qcow2 snapshots > unrelated here.. It's fuzzy. From the guest point of view, we are serving a single guest image by use of multiple files in the host. I will do s/level/layer/, to match the wording I already had on the next line: > 10: NBD_STATE_DEPTH_BACKING, the extent is inherited from a > backing layer -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org