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=-7.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 F1622C433C1 for ; Thu, 25 Mar 2021 15:15:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C13CA61A2A for ; Thu, 25 Mar 2021 15:15:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230241AbhCYPOt (ORCPT ); Thu, 25 Mar 2021 11:14:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:35698 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231375AbhCYPOi (ORCPT ); Thu, 25 Mar 2021 11:14:38 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 92E8861879; Thu, 25 Mar 2021 15:14:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616685278; bh=EbycO/deHFM530+ruOu412p0Jfev3nG2KiWakLqetXo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=dxlUVWMHYwvolg6D/CjQEqHhZ1nmoq17qMz33zAghoiiqto221fGWVmcGAplrNtoK FMSy00KeLMdiGsAQkfde4zgyl6QTJgk33R1t190q5furIs2W41ujDs+DRFrGr5FGbU m8BO7nNGIIhfTf8GFvPbvvmHYI67E5vQHhIY2ZGeqi8DxwMFvRHgCE0meXUhJ86VE7 qBmQx363VMisDJL0QFDNfS9915xjXpvXdz723YeODrCj7KTtWBafBLOlGL/vQADyR0 ZZVxpdDCmqNK/bDFLdD7VzSP/gau4R5mOOOfwgXovYPyYkDE6zcKEgcVQaf1bzVRhw HVyAzyDbCYWYQ== Date: Fri, 26 Mar 2021 00:14:33 +0900 From: Keith Busch To: Niklas Cassel Cc: "javier@javigon.com" , "linux-nvme@lists.infradead.org" , "sagi@grimberg.me" , "linux-block@vger.kernel.org" , "minwoo.im.dev@gmail.com" , Javier =?iso-8859-1?Q?Gonz=E1lez?= , "hch@lst.de" Subject: Re: [PATCH V6 1/2] nvme: enable char device per namespace Message-ID: <20210325151433.GA31394@redsun51.ssa.fujisawa.hgst.com> References: <20210301192452.16770-1-javier.gonz@samsung.com> <20210301192452.16770-2-javier.gonz@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Thu, Mar 25, 2021 at 12:25:24PM +0000, Niklas Cassel wrote: > On Mon, Mar 01, 2021 at 08:24:51PM +0100, javier@javigon.com wrote: > > From: Javier González > > > > Create a char device per NVMe namespace. This char device is always > > initialized, independently of whether the features implemented by the > > device are supported by the kernel. User-space can therefore always > > issue IOCTLs to the NVMe driver using the char device. > > > > The char device is presented as /dev/nvme-generic-XcYnZ. This naming > > scheme follows the convention of the hidden device (nvmeXcYnZ). Support > > for multipath will follow. > > Do we perhaps want to put these new character devices inside a subdir? > e.g. /dev/nvme/nvme-generic-XcYnZ ? I actually suggested the same hierarchy, but that was rejected. > Otherwise it feels like doing such a simple thing as ls -al /dev/nvme* > will show a lot of devices because of these new specialized char devices.