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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,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 EDFF1C433ED for ; Mon, 17 May 2021 15:02:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D111561019 for ; Mon, 17 May 2021 15:02:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241082AbhEQPEE (ORCPT ); Mon, 17 May 2021 11:04:04 -0400 Received: from mx2.suse.de ([195.135.220.15]:50058 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242278AbhEQPCD (ORCPT ); Mon, 17 May 2021 11:02:03 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id D180AAEBB; Mon, 17 May 2021 15:00:45 +0000 (UTC) Date: Mon, 17 May 2021 17:00:43 +0200 From: Petr Vorel To: NeilBrown Cc: "J . Bruce Fields" , linux-nfs@vger.kernel.org, Steve Dickson , Chuck Lever , Alexey Kodanev Subject: Re: [PATCH/RFC v2 nfs-utils] Fix NFSv4 export of tmpfs filesystems. Message-ID: Reply-To: Petr Vorel References: <20210422191803.31511-1-pvorel@suse.cz> <20210422202334.GB25415@fieldses.org> <162035212343.24322.12361160756597283121@noble.neil.brown.name> <162122673178.19062.96081788305923933@noble.neil.brown.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <162122673178.19062.96081788305923933@noble.neil.brown.name> Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Hi Neil, > Some filesystems cannot be exported without an fsid or uuid. > tmpfs is the main example. > When mountd (or exportd) creates nfsv4 pseudo-root exports for the path > leading down to an export point it exports each directory without any > fsid or uuid. If one of these directories is on tmp, that will fail. > The net result is that exporting a subdirectory of a tmpfs filesystem > will not work over NFSv4 as the parents within the filesystem cannot be > exported. It will either fail, or fall-back to NFSv3 (depending on the > version of the mount.nfs program). > To fix this we need to provide an fsid or uuid for these pseudo-root > exports. This patch does that by creating an RFC-4122 V5 compatible > UUID based on an arbitrary seed and the path to the export. > To check if an export needs a uuid, text_export() is moved from exportfs > to libexport.a, modified slightly and renamed to export_test(). > Signed-off-by: NeilBrown Tested-by: Petr Vorel tmpfs and btrfs via LTP test nfs01 on openSUSE. Kind regards, Petr