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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 7C718C3A59E for ; Mon, 2 Sep 2019 13:56:22 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 58F39217F4 for ; Mon, 2 Sep 2019 13:56:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 58F39217F4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=driverdev-devel-bounces@linuxdriverproject.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 3B357858F7; Mon, 2 Sep 2019 13:56:22 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gok0IC8w6DJS; Mon, 2 Sep 2019 13:56:19 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by fraxinus.osuosl.org (Postfix) with ESMTP id 430DC85778; Mon, 2 Sep 2019 13:56:19 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by ash.osuosl.org (Postfix) with ESMTP id 80E291BF408 for ; Mon, 2 Sep 2019 13:56:18 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 79BC085CB4 for ; Mon, 2 Sep 2019 13:56:18 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id UXjHFkbQZZdi for ; Mon, 2 Sep 2019 13:56:16 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from huawei.com (szxga03-in.huawei.com [45.249.212.189]) by whitealder.osuosl.org (Postfix) with ESMTPS id 0D5C1843BB for ; Mon, 2 Sep 2019 13:56:15 +0000 (UTC) Received: from DGGEMM401-HUB.china.huawei.com (unknown [172.30.72.56]) by Forcepoint Email with ESMTP id 483E9D60EC475B9922D5; Mon, 2 Sep 2019 21:56:12 +0800 (CST) Received: from dggeme762-chm.china.huawei.com (10.3.19.108) by DGGEMM401-HUB.china.huawei.com (10.3.20.209) with Microsoft SMTP Server (TLS) id 14.3.439.0; Mon, 2 Sep 2019 21:56:11 +0800 Received: from architecture4 (10.140.130.215) by dggeme762-chm.china.huawei.com (10.3.19.108) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1591.10; Mon, 2 Sep 2019 21:56:11 +0800 Date: Mon, 2 Sep 2019 21:55:20 +0800 From: Gao Xiang To: Subject: Re: [PATCH v6 05/24] erofs: add inode operations Message-ID: <20190902135519.GD2664@architecture4> References: <20190802125347.166018-1-gaoxiang25@huawei.com> <20190802125347.166018-6-gaoxiang25@huawei.com> <20190829102426.GE20598@infradead.org> <20190901093326.GA6267@hsiangkao-HP-ZHAN-66-Pro-G1> <20190902134329.GU2752@twin.jikos.cz> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190902134329.GU2752@twin.jikos.cz> User-Agent: Mutt/1.9.4 (2018-02-28) X-Originating-IP: [10.140.130.215] X-ClientProxiedBy: dggeme707-chm.china.huawei.com (10.1.199.103) To dggeme762-chm.china.huawei.com (10.3.19.108) X-CFilter-Loop: Reflected X-BeenThere: driverdev-devel@linuxdriverproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Driver Project Developer List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devel@driverdev.osuosl.org, Stephen Rothwell , linux-erofs@lists.ozlabs.org, Amir Goldstein , Jan Kara , "Darrick J . Wong" , Linus Torvalds , Dave Chinner , LKML , Theodore Ts'o , Christoph Hellwig , Greg Kroah-Hartman , Alexander Viro , Pavel Machek , linux-fsdevel@vger.kernel.org, Jaegeuk Kim , Andrew Morton , Miao Xie Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" Hi David, On Mon, Sep 02, 2019 at 03:43:29PM +0200, David Sterba wrote: > On Sun, Sep 01, 2019 at 05:34:00PM +0800, Gao Xiang wrote: > > > > +static int read_inode(struct inode *inode, void *data) > > > > +{ > > > > + struct erofs_vnode *vi = EROFS_V(inode); > > > > + struct erofs_inode_v1 *v1 = data; > > > > + const unsigned int advise = le16_to_cpu(v1->i_advise); > > > > + erofs_blk_t nblks = 0; > > > > + > > > > + vi->datamode = __inode_data_mapping(advise); > > > > > > What is the deal with these magic underscores here and various > > > other similar helpers? > > > > Fixed in > > https://lore.kernel.org/linux-fsdevel/20190901055130.30572-17-hsiangkao@aol.com/ > > > > underscores means 'internal' in my thought, it seems somewhat > > some common practice of Linux kernel, or some recent discussions > > about it?... I didn't notice these discussions... > > I know about a few valid uses of the underscores: > > * pattern where the __underscored version does not do locking, while the other > does > * similarly for atomic and non-atomic version > * macro that needs to manipulate the argument name (like glue some > prefix, so the macro does not have underscores and is supposed to be > used instead of the function with underscores that needs the full name > of a variable/constant/.. > * underscore function takes a few more parameters to further tune the > behaviour, but most users are fine with the defaults and that is > provided as a function without underscores > * in case you have just one function of the kind, don't use the underscores > > I can lookup examples if you're interested or if the brief description > is not sufficient. The list covers what I've seen and used, but the list > may be incomplete. Thanks, I learn a lot from the above. [thumb] Thanks, Gao Xiang _______________________________________________ devel mailing list devel@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel