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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 8DD44C46460 for ; Tue, 14 Aug 2018 15:39:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3CF9121734 for ; Tue, 14 Aug 2018 15:39:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3CF9121734 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732717AbeHNS1D (ORCPT ); Tue, 14 Aug 2018 14:27:03 -0400 Received: from mx2.suse.de ([195.135.220.15]:51856 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728458AbeHNS1D (ORCPT ); Tue, 14 Aug 2018 14:27:03 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 1B778AECF; Tue, 14 Aug 2018 15:39:22 +0000 (UTC) Subject: Re: [PATCH 2/5] nvme: register ns_id attributes as default sysfs groups To: Bart Van Assche , "axboe@kernel.dk" Cc: "hch@lst.de" , "linux-kernel@vger.kernel.org" , "keith.busch@intel.com" , "linux-nvme@lists.infradead.org" , "linux-block@vger.kernel.org" , "hare@suse.com" , "sagi@grimberg.me" References: <20180814073305.87255-1-hare@suse.de> <20180814073305.87255-3-hare@suse.de> <5a4aab8b5f509d8090ad10107b01d11285fe1528.camel@wdc.com> From: Hannes Reinecke Message-ID: Date: Tue, 14 Aug 2018 17:39:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <5a4aab8b5f509d8090ad10107b01d11285fe1528.camel@wdc.com> Content-Type: text/plain; charset=UTF-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/14/2018 05:20 PM, Bart Van Assche wrote: > On Tue, 2018-08-14 at 09:33 +0200, Hannes Reinecke wrote: >> +const struct attribute_group *nvme_ns_id_attr_groups[] = { >> + &nvme_ns_id_attr_group, >> + NULL, /* Will be filled in by lightnvm if present */ >> + NULL, >> +}; > [ ... ] >> -void nvme_nvm_unregister_sysfs(struct nvme_ns *ns) >> -{ >> - struct nvm_dev *ndev = ns->ndev; >> - struct nvm_geo *geo = &ndev->geo; >> + return; >> >> switch (geo->major_ver_id) { >> case 1: >> - sysfs_remove_group(&disk_to_dev(ns->disk)->kobj, >> - &nvm_dev_attr_group_12); >> + nvme_ns_id_attr_groups[1] = &nvm_dev_attr_group_12; >> break; >> case 2: >> - sysfs_remove_group(&disk_to_dev(ns->disk)->kobj, >> - &nvm_dev_attr_group_20); >> + nvme_ns_id_attr_groups[1] = &nvm_dev_attr_group_20; > > This patch introduces a really ugly dependency between the NVMe core code and > the lightnvm code, namely that the lightnvm code has to know at which position > in the nvme_ns_id_attr_groups it can fill in its attribute group pointer. Have > you considered to make nvme_nvm_register_sysfs() return an attribute group > pointer such that the nvme_ns_id_attr_groups can be changed from a global into > a static array? > Wouldn't help much, as the 'nvme_ns_id_attr_groups' needs to be a global pointer anyway as it's references from drivers/nvme/host/core.c and drivers/nvme/host/multipath.c. While I have considered having nvme_nvm_register_sysfs() returning a pointer I would then have to remove the 'static' declaration from the nvm_dev_attr_group_12/20. Which I didn't really like, either. Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)