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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 A51BCC43219 for ; Fri, 26 Apr 2019 12:56:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 77D18206BF for ; Fri, 26 Apr 2019 12:56:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726154AbfDZM4M (ORCPT ); Fri, 26 Apr 2019 08:56:12 -0400 Received: from fieldses.org ([173.255.197.46]:52824 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726013AbfDZM4M (ORCPT ); Fri, 26 Apr 2019 08:56:12 -0400 Received: by fieldses.org (Postfix, from userid 2815) id 83D5B1C83; Fri, 26 Apr 2019 08:56:11 -0400 (EDT) Date: Fri, 26 Apr 2019 08:56:11 -0400 To: Andreas Dilger Cc: NeilBrown , "J. Bruce Fields" , linux-nfs , linux-fsdevel , abe@purdue.edu, lsof-l@lists.purdue.edu, util-linux@vger.kernel.org, Jeff Layton , James Simmons Subject: Re: [PATCH 00/10] exposing knfsd opens to userspace Message-ID: <20190426125611.GA23112@fieldses.org> References: <1556201060-7947-1-git-send-email-bfields@redhat.com> <87lfzx65ax.fsf@notabene.neil.brown.name> <60EB550C-B79C-4DB4-AE3D-F1FCEB49EDA1@dilger.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <60EB550C-B79C-4DB4-AE3D-F1FCEB49EDA1@dilger.ca> User-Agent: Mutt/1.5.21 (2010-09-15) From: bfields@fieldses.org (J. Bruce Fields) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, Apr 26, 2019 at 01:00:19PM +0200, Andreas Dilger wrote: > > On Apr 26, 2019, at 1:20 AM, NeilBrown wrote: > > /proc/fs/nfsd is the (standard) mount point for a separate NFSD-specific > > filesystem, originally created to replace the nfsd-specific systemcall. > > So the nfsd developers have a fair degree of latitude as to what can go > > in there. > > > > But I *don't* think it is a good idea to follow this pattern. Creating > > a separate control filesystem for every different module that thinks it > > has different needs doesn't scale well. We could end up with dozens of > > tiny filesystems that all need to be mounted at just the right place. Aren't we already there? My laptop, Fedora 29 with everything pretty much default: $ findmnt -n -oFSTYPE|sort|uniq -c 1 autofs 1 bpf 11 cgroup 1 cgroup2 1 configfs 1 debugfs 1 devpts 1 devtmpfs 3 ext4 1 fusectl 1 fuse.gvfsd-fuse 1 hugetlbfs 1 mqueue 1 proc 1 pstore 1 rpc_pipefs 1 securityfs 1 selinuxfs 1 sysfs 5 tmpfs > > I don't think that is healthy for Linus. What are the problems you see? > > Nor do I think we should be stuffing stuff into debugfs that isn't > > really for debugging. That isn't healthy either. > > > > If sysfs doesn't meet our needs, then we need to raise that in > > appropriate fora and present a clear case and try to build consensus - > > because if we see a problem, then it is likely that others do to. > > I definitely *do* see the restrictions sysfs as being a problem, and I'd > guess NFS developers thought the same, For what it's worth, the nfsd filesystem predated sysfs, just barely. Looking at the history.... It was actually Al that introduced it in March 2002. Patrick Mochel added sysfs in October 2002. But it's true that from the start nfsd didn't really fit the model of a single (possibly writeable) attribute per file. (Might be interesting to look at the distribution of new filesystem types over time, there may have been a peak around then.) --b.