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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 80431C28CC0 for ; Wed, 29 May 2019 22:12:21 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 575122426D for ; Wed, 29 May 2019 22:12:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 575122426D 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 ([127.0.0.1]:35813 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hW6o0-0006cd-JU for qemu-devel@archiver.kernel.org; Wed, 29 May 2019 18:12:20 -0400 Received: from eggs.gnu.org ([209.51.188.92]:49706) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hW6mJ-0005Or-Ji for qemu-devel@nongnu.org; Wed, 29 May 2019 18:10:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hW6mI-0000sr-Nf for qemu-devel@nongnu.org; Wed, 29 May 2019 18:10:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36578) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hW6mD-0000nc-2u; Wed, 29 May 2019 18:10:30 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id C2D452CE945; Wed, 29 May 2019 22:10:18 +0000 (UTC) Received: from localhost.localdomain (ovpn-116-55.ams2.redhat.com [10.36.116.55]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2E6007A404; Wed, 29 May 2019 22:10:12 +0000 (UTC) Date: Thu, 30 May 2019 00:10:10 +0200 From: Kevin Wolf To: Max Reitz Message-ID: <20190529221010.GC3471@localhost.localdomain> References: <20190524172812.27308-1-mreitz@redhat.com> <20190524172812.27308-2-mreitz@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190524172812.27308-2-mreitz@redhat.com> User-Agent: Mutt/1.11.3 (2019-02-01) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Wed, 29 May 2019 22:10:23 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [RFC 1/3] block: Add ImageRotationalInfo 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: Alberto Garcia , Anton Nefedov , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, qemu-block@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 24.05.2019 um 19:28 hat Max Reitz geschrieben: > This enum indicates whether a file is stored on a rotating disk or a > solid-state drive. Drivers report it via the .bdrv_get_info() callback, > and if they do not, the global bdrv_get_info() implementation > automatically takes it from bs->file or bs->backing, if available. Good that you wrote "bs->file or bs->backing" explicitly. Otherwise, I might have missed that it begs one big question: What is the correct answer for a qcow2 file that has bs->file on an SSD, but bs->backing on a rotating disk? I don't think there is a correct answer for the whole device, so maybe this information shouldn't be per device in BlockDriverInfo, but per block in bdrv_co_block_status() (optionally determined if the caller requests it)? Kevin