From nobody Tue Nov 11 00:25:26 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1559835770; cv=none; d=zoho.com; s=zohoarc; b=efO9jABOzJB5g1+WhprwO0O7w1wR/kTakn4LGFfpxDSJK8uSScJshQ/xMzgSezFViBfFv46JSxoLMlNDEeY6t9qFSlNun1+W+aplOhLWbNqabA95GzOX41gdJi+gktgDSaNWo89LldytbfTQJq33pHR7i+F4s4LS35Fq3Vw+Mhk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1559835770; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=zau79DhQWoweVRxL9squ15QY7ULlHDJOFzI/tUtHsHQ=; b=nkE9z8J0rZMUNZyHY1HAMLFMN2WRWzwvprdYt2cyr5fVgmUDsa3zXPI7SrGY/Y0yKThXk/yHKbgLIgMCv3KSnB5ECFHUs63IQgA4aHi3kruf11rY5MxEMk9nEwcFStAbpmFAbveQZXywZ/Wefk4ZVYffTw/3AKXTNuQVU2C/1Lk= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1559835770249490.2569685090592; Thu, 6 Jun 2019 08:42:50 -0700 (PDT) Received: from localhost ([127.0.0.1]:34170 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hYuXQ-00015N-Pk for importer@patchew.org; Thu, 06 Jun 2019 11:42:48 -0400 Received: from eggs.gnu.org ([209.51.188.92]:43294) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hYuT5-0005oa-Db for qemu-devel@nongnu.org; Thu, 06 Jun 2019 11:38:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hYuT4-00064A-DN for qemu-devel@nongnu.org; Thu, 06 Jun 2019 11:38:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35558) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hYuT1-0005tf-S1; Thu, 06 Jun 2019 11:38:15 -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 0ACCD30C2534; Thu, 6 Jun 2019 15:38:10 +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 BAFD07D909; Thu, 6 Jun 2019 15:38:08 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 9999F11385D0; Thu, 6 Jun 2019 17:38:03 +0200 (CEST) From: Markus Armbruster To: qemu-devel@nongnu.org Date: Thu, 6 Jun 2019 17:38:02 +0200 Message-Id: <20190606153803.5278-7-armbru@redhat.com> In-Reply-To: <20190606153803.5278-1-armbru@redhat.com> References: <20190606153803.5278-1-armbru@redhat.com> MIME-Version: 1.0 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 [10.5.110.40]); Thu, 06 Jun 2019 15:38:10 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH 6/7] file-posix: Add dynamic-auto-read-only QAPI feature X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, pkrempa@redhat.com, qemu-block@nongnu.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" From: Kevin Wolf In commit 23dece19da4 ('file-posix: Make auto-read-only dynamic') , auto-read-only=3Don 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 t= he +# driver will open the image read-only at first, +# dynamically reopen the image file read-write wh= en +# the first writer is attached to the node and re= open +# read-only when the last writer is detached. This +# allows to give QEMU write permissions only on d= emand +# 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)' } ] } =20 ## # @BlockdevOptionsNull: --=20 2.21.0