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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 34CA6C433DF for ; Mon, 1 Jun 2020 05:28:28 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 09FFF206E2 for ; Mon, 1 Jun 2020 05:28:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 09FFF206E2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jfczC-0006X3-IN; Mon, 01 Jun 2020 05:27:46 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jfczB-0006Wy-Gt for xen-devel@lists.xenproject.org; Mon, 01 Jun 2020 05:27:45 +0000 X-Inumbo-ID: 9e1cd922-a3c8-11ea-aaee-12813bfff9fa Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 9e1cd922-a3c8-11ea-aaee-12813bfff9fa; Mon, 01 Jun 2020 05:27:43 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 80141B03E; Mon, 1 Jun 2020 05:27:43 +0000 (UTC) Subject: Re: [PATCH v10 05/12] libs: add libxenhypfs To: Andrew Cooper , xen-devel@lists.xenproject.org References: <20200519072106.26894-1-jgross@suse.com> <20200519072106.26894-6-jgross@suse.com> <8468b7ea-81ba-0512-c638-322803134576@citrix.com> From: =?UTF-8?B?SsO8cmdlbiBHcm/Dnw==?= Message-ID: <91bd61d3-3f61-c8c8-8f7b-4547eb02b342@suse.com> Date: Mon, 1 Jun 2020 07:27:40 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <8468b7ea-81ba-0512-c638-322803134576@citrix.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Stefano Stabellini , Julien Grall , Wei Liu , Paul Durrant , Ian Jackson , George Dunlap , Jan Beulich Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" On 30.05.20 17:54, Andrew Cooper wrote: > On 19/05/2020 08:20, Juergen Gross wrote: >> diff --git a/tools/libs/hypfs/include/xenhypfs.h b/tools/libs/hypfs/include/xenhypfs.h >> new file mode 100644 >> index 0000000000..ab157edceb >> --- /dev/null >> +++ b/tools/libs/hypfs/include/xenhypfs.h >> @@ -0,0 +1,90 @@ >> +/* >> + * Copyright (c) 2019 SUSE Software Solutions Germany GmbH >> + * >> + * This library is free software; you can redistribute it and/or >> + * modify it under the terms of the GNU Lesser General Public >> + * License as published by the Free Software Foundation; >> + * version 2.1 of the License. >> + * >> + * This library is distributed in the hope that it will be useful, >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU >> + * Lesser General Public License for more details. >> + * >> + * You should have received a copy of the GNU Lesser General Public >> + * License along with this library; If not, see . >> + */ >> +#ifndef XENHYPFS_H >> +#define XENHYPFS_H >> + >> +#include >> +#include >> +#include >> + >> +/* Callers who don't care don't need to #include */ >> +struct xentoollog_logger; >> + >> +typedef struct xenhypfs_handle xenhypfs_handle; >> + >> +struct xenhypfs_dirent { >> + char *name; >> + size_t size; >> + enum { >> + xenhypfs_type_dir, >> + xenhypfs_type_blob, >> + xenhypfs_type_string, >> + xenhypfs_type_uint, >> + xenhypfs_type_int, >> + xenhypfs_type_bool >> + } type; >> + enum { >> + xenhypfs_enc_plain, >> + xenhypfs_enc_gzip >> + } encoding; >> + bool is_writable; >> +}; > > I'm afraid this a blocker bug for 4.14. > > enum's aren't safe in public ABI structs, even under _GNU_SOURCE.  Use > unsigned int's, and declare the enumerations earlier. > > There is also 3/7 bytes of trailing padding and very little forward > extensibility.  How about an unsigned int flags, of which writeable is > the bottom bit, seeing as this is purely an informational field? Sounds fine. I'll send a patch on Tuesday (today is a local holiday in Germany and I need to do some outdoor work). Juergen