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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 AE65AC31E46 for ; Wed, 12 Jun 2019 16:33:24 +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 8B0E821019 for ; Wed, 12 Jun 2019 16:33:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8B0E821019 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]:33714 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hb6Be-0001i8-Vy for qemu-devel@archiver.kernel.org; Wed, 12 Jun 2019 12:33:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53123) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hb6A3-0000qQ-N9 for qemu-devel@nongnu.org; Wed, 12 Jun 2019 12:31:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hb6A2-0006Az-NM for qemu-devel@nongnu.org; Wed, 12 Jun 2019 12:31:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60664) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hb6A0-00067X-Cr; Wed, 12 Jun 2019 12:31:40 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id 9947330C252E; Wed, 12 Jun 2019 16:31:28 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-148.ams2.redhat.com [10.36.116.148]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 66297608A6; Wed, 12 Jun 2019 16:31:27 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 0E87E1138648; Wed, 12 Jun 2019 18:31:26 +0200 (CEST) From: Markus Armbruster To: Eric Blake References: <20190606153803.5278-1-armbru@redhat.com> <20190606153803.5278-7-armbru@redhat.com> <2d2f4567-1b35-6586-e195-a89b398e676c@redhat.com> Date: Wed, 12 Jun 2019 18:31:26 +0200 In-Reply-To: <2d2f4567-1b35-6586-e195-a89b398e676c@redhat.com> (Eric Blake's message of "Thu, 6 Jun 2019 10:54:16 -0500") Message-ID: <877e9qwysh.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Wed, 12 Jun 2019 16:31:38 +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] [PATCH 6/7] file-posix: Add dynamic-auto-read-only QAPI feature 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, pkrempa@redhat.com, qemu-devel@nongnu.org, qemu-block@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Eric Blake writes: > On 6/6/19 10:38 AM, Markus Armbruster wrote: >> From: Kevin Wolf >> >> In commit 23dece19da4 ('file-posix: Make auto-read-only dynamic') , >> auto-read-only=on changed its behaviour in file-posix for the 4.0 >> release. This change cannot be detected through the usual mechanisms >> like schema introspection. Add a new feature flag to the schema to >> allow libvirt to detect the presence of the new behaviour. >> >> Signed-off-by: Kevin Wolf >> --- >> qapi/block-core.json | 13 ++++++++++++- >> 1 file changed, 12 insertions(+), 1 deletion(-) >> >> diff --git a/qapi/block-core.json b/qapi/block-core.json >> index 1defcde048..f5e1ee91f9 100644 >> --- a/qapi/block-core.json >> +++ b/qapi/block-core.json >> @@ -2859,6 +2859,15 @@ >> # file is large, do not use in production. >> # (default: off) (since: 3.0) >> # >> +# Features: >> +# @dynamic-auto-read-only: If present, enabled auto-read-only means that the >> +# driver will open the image read-only at first, >> +# dynamically reopen the image file read-write when >> +# the first writer is attached to the node and reopen >> +# read-only when the last writer is detached. This >> +# allows to give QEMU write permissions only on demand > > s/allows to give/allows giving/ Fixing, thanks! >> +# when an operation actually needs write access. >> +# >> # Since: 2.9 >> ## >> { 'struct': 'BlockdevOptionsFile', >> @@ -2868,7 +2877,9 @@ >> '*aio': 'BlockdevAioOptions', >> '*drop-cache': {'type': 'bool', >> 'if': 'defined(CONFIG_LINUX)'}, >> - '*x-check-cache-dropped': 'bool' } } >> + '*x-check-cache-dropped': 'bool' }, >> + 'features': [ { 'name': 'dynamic-auto-read-only', >> + 'if': 'defined(CONFIG_POSIX)' } ] } >> >> ## >> # @BlockdevOptionsNull: >>