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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id D71E2C5478C for ; Wed, 28 Feb 2024 11:59:31 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rfIZw-0007pA-73; Wed, 28 Feb 2024 06:58:28 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rfIZu-0007oZ-IS for qemu-devel@nongnu.org; Wed, 28 Feb 2024 06:58:26 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rfIZt-00073w-0j for qemu-devel@nongnu.org; Wed, 28 Feb 2024 06:58:26 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1709121503; 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=VRdAQ551NkGobukhi+9r4yjHrWN/nSBAekiV+icfRhU=; b=RzuTK4LhnrLG8QCgi0DZ5Bdiq5TMtyDpSCzsjl+TVhF/p0m3Dn1dgi54tsXFZkoGv+5RVp sFtwgMgz8lrNVWH/o5egN4Ea59yiIXnt4pczrIpQRlSEGdhf4nbJqdkyV6SXlT8ZgNpcDA GP5Mn/FjLfbKLSo5QQoxh20JTXMPPbU= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-588-Se3dibaUMeK1WN2Gbx53RA-1; Wed, 28 Feb 2024 06:58:22 -0500 X-MC-Unique: Se3dibaUMeK1WN2Gbx53RA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 36A561C0513F; Wed, 28 Feb 2024 11:58:22 +0000 (UTC) Received: from redhat.com (unknown [10.39.192.233]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 40E18C0348D; Wed, 28 Feb 2024 11:58:21 +0000 (UTC) Date: Wed, 28 Feb 2024 12:58:20 +0100 From: Kevin Wolf To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= Cc: Markus Armbruster , Yong Huang , qemu-devel@nongnu.org, Hanna Reitz , Eric Blake Subject: Re: [PATCH] qapi: Craft the BlockdevCreateOptionsLUKS comment Message-ID: References: <91c52e03e46ff0a96559b4e7d66ded582b2ec4e1.1708486450.git.yong.huang@smartx.com> <874je22u83.fsf@pond.sub.org> <875xyiz0ho.fsf@pond.sub.org> <87v8693x7c.fsf@pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com 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=-0.102, 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Am 28.02.2024 um 12:30 hat Daniel P. Berrangé geschrieben: > On Wed, Feb 28, 2024 at 11:17:37AM +0100, Kevin Wolf wrote: > > Until now, @size has been mandatory for creating images with every > > driver. Maybe we should even have put it into BlockdevCreateOptions's > > base, because without a size, you're not really creating an image. > > NB, @size isn't mandatory for creating images. It isn't required > when creating qcow2 files with backing stores, as the size is > acquired from the backing file instead. > > $ qemu-img create demo.raw 1g > Formatting 'demo.raw', fmt=raw size=1073741824 > $ qemu-img create -o backing_file=demo.raw -o backing_fmt=raw -f qcow2 demo.qcow2 > Formatting 'demo.qcow2', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=1073741824 backing_file=demo.raw backing_fmt=raw lazy_refcounts=off refcount_bits=16 Yes, 'qemu-img create' is different, it adds some convenience magic like this. But for 'blockdev-create', it's mandatory for every driver. I double checked the QAPI schema. Kevin