From owner-svn-src-all@freebsd.org Wed Aug 2 11:43:08 2017 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 1EBC8DCE273; Wed, 2 Aug 2017 11:43:08 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id A337C2065; Wed, 2 Aug 2017 11:43:07 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kib@localhost [127.0.0.1]) by kib.kiev.ua (8.15.2/8.15.2) with ESMTPS id v72Bh3u6023624 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 2 Aug 2017 14:43:03 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua v72Bh3u6023624 Received: (from kostik@localhost) by tom.home (8.15.2/8.15.2/Submit) id v72Bh3L4023623; Wed, 2 Aug 2017 14:43:03 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Wed, 2 Aug 2017 14:43:03 +0300 From: Konstantin Belousov To: Hans Petter Selasky Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r321920 - head/sys/sys Message-ID: <20170802114303.GE1700@kib.kiev.ua> References: <201708021014.v72AEHEk061037@repo.freebsd.org> <7b1d274f-a531-f788-742a-a8375fe76763@selasky.org> <20170802110607.GC1700@kib.kiev.ua> <760e0077-499e-fffb-a86b-979e410b35e1@selasky.org> <20170802111752.GD1700@kib.kiev.ua> <912d42d0-ea07-82ec-e754-f6b6d2b4cc94@selasky.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <912d42d0-ea07-82ec-e754-f6b6d2b4cc94@selasky.org> User-Agent: Mutt/1.8.3 (2017-05-23) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.1 X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on tom.home X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 02 Aug 2017 11:43:08 -0000 On Wed, Aug 02, 2017 at 01:27:50PM +0200, Hans Petter Selasky wrote: > On 08/02/17 13:17, Konstantin Belousov wrote: > > But y must be dev_t. > > Sure, but "struct cdev" 's si_drv0 is only "int" . How can it contain > dev_t ? Why should it contain dev_t ? Linux KPI abused that field it seems. Lets change the focus of the discussion. You cited the struct linux_cdev * linux_find_cdev(const char *name, unsigned major, unsigned minor) function which finds cdev (or some mockup of the native cdev) by major/minor. Where does these major/minor numbers come from ? I mean that if they are contructed as major(struct stat.st_rdev) and minor(struct stat.st_rdev), then even the original code looks wrong without the ino64 addition. Since devfs reports the internal inode number into st_rdev, which formally is not accessible outside the devfs filesystem. So should the code for linux_find_cdev() changed to match cdevs against inode number ? cdp_inode is serially generated so on real machine it is really a small number for any /dev node. You can watch that by ls -l /dev.