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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 174EEC388F9 for ; Wed, 11 Nov 2020 07:58:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BE7AB206B5 for ; Wed, 11 Nov 2020 07:58:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726239AbgKKH6A (ORCPT ); Wed, 11 Nov 2020 02:58:00 -0500 Received: from verein.lst.de ([213.95.11.211]:39089 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726091AbgKKH56 (ORCPT ); Wed, 11 Nov 2020 02:57:58 -0500 Received: by verein.lst.de (Postfix, from userid 2407) id A53F767373; Wed, 11 Nov 2020 08:57:54 +0100 (CET) Date: Wed, 11 Nov 2020 08:57:54 +0100 From: Christoph Hellwig To: Jens Axboe Cc: Greg Kroah-Hartman , "Rafael J. Wysocki" , Denis Efremov , "David S. Miller" , Song Liu , Al Viro , Finn Thain , Michael Schmitz , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, linux-raid@vger.kernel.org, linux-scsi@vger.kernel.org, linux-m68k@lists.linux-m68k.org Subject: Re: simplify gendisk lookup and remove struct block_device aliases v4 Message-ID: <20201111075754.GA23010@lst.de> References: <20201029145841.144173-1-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201029145841.144173-1-hch@lst.de> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jens, can you take a look and possibly pick this series up? On Thu, Oct 29, 2020 at 03:58:23PM +0100, Christoph Hellwig wrote: > Hi all, > > this series removes the annoying struct block_device aliases, which can > happen for a bunch of old floppy drivers (and z2ram). In that case > multiple struct block device instances for different dev_t's can point > to the same gendisk, without being partitions. The cause for that > is the probe/get callback registered through blk_register_regions. > > This series removes blk_register_region entirely, splitting it it into > a simple xarray lookup of registered gendisks, and a probe callback > stored in the major_names array that can be used for modprobe overrides > or creating devices on demands when no gendisk is found. The old > remapping is gone entirely, and instead the 4 remaining drivers just > register a gendisk for each operating mode. In case of the two drivers > that have lots of aliases that is done on-demand using the new probe > callback, while for the other two I simply register all at probe time > to keep things simple. > > Note that the m68k drivers are compile tested only. > > Changes since v3: > - keep kobj_map for char dev lookup for now, as the testbot found > some very strange and unexplained regressions, so I'll get back to > this later separately > - fix a commit message typo > > Changes since v2: > - fix a wrong variable passed to ERR_PTR in the floppy driver > - slightly adjust the del_gendisk cleanups to prepare for the next > series touching this area > > Changes since v1: > - add back a missing kobject_put in the cdev code > - improve the xarray delete loops ---end quoted text---