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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 A7C3EC3815B for ; Wed, 15 Apr 2020 12:52:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91C2C206D5 for ; Wed, 15 Apr 2020 12:52:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S370518AbgDOMwJ (ORCPT ); Wed, 15 Apr 2020 08:52:09 -0400 Received: from mx2.suse.de ([195.135.220.15]:34220 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S370492AbgDOMvv (ORCPT ); Wed, 15 Apr 2020 08:51:51 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 27143AC11; Wed, 15 Apr 2020 12:51:49 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id DE49C1E1250; Wed, 15 Apr 2020 14:51:47 +0200 (CEST) Date: Wed, 15 Apr 2020 14:51:47 +0200 From: Jan Kara To: ira.weiny@intel.com Cc: linux-kernel@vger.kernel.org, Jan Kara , "Darrick J. Wong" , Dan Williams , Dave Chinner , Christoph Hellwig , "Theodore Y. Ts'o" , Jeff Moyer , linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH RFC 5/8] fs/ext4: Make DAX mount option a tri-state Message-ID: <20200415125147.GH6126@quack2.suse.cz> References: <20200414040030.1802884-1-ira.weiny@intel.com> <20200414040030.1802884-6-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200414040030.1802884-6-ira.weiny@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 13-04-20 21:00:27, ira.weiny@intel.com wrote: > From: Ira Weiny > > We add 'always', 'never', and 'inode' (default). '-o dax' continue to > operate the same. > > Specifically we introduce a 2nd DAX mount flag EXT4_MOUNT_NODAX and set > it and EXT4_MOUNT_DAX appropriately. > > We also force EXT4_MOUNT_NODAX if !CONFIG_FS_DAX. > > https://lore.kernel.org/lkml/20200405061945.GA94792@iweiny-DESK2.sc.intel.com/ > > Signed-off-by: Ira Weiny ... > @@ -2303,6 +2325,13 @@ static int _ext4_show_options(struct seq_file *seq, struct super_block *sb, > if (DUMMY_ENCRYPTION_ENABLED(sbi)) > SEQ_OPTS_PUTS("test_dummy_encryption"); > > + if (test_opt2(sb, NODAX)) > + SEQ_OPTS_PUTS("dax=never"); > + else if (test_opt(sb, DAX)) > + SEQ_OPTS_PUTS("dax=always"); > + else > + SEQ_OPTS_PUTS("dax=inode"); > + We try to show only mount options that were explicitely set by the user, or that are different from defaults - e.g., see how 'data=' mount option printing is handled. > ext4_show_quota_options(seq, sb); > return 0; > } > @@ -5424,6 +5453,12 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) > sbi->s_mount_opt ^= EXT4_MOUNT_DAX; > } > > + if ((sbi->s_mount_opt2 ^ old_opts.s_mount_opt2) & EXT4_MOUNT2_NODAX) { > + ext4_msg(sb, KERN_WARNING, "warning: refusing change of " > + "non-dax flag with busy inodes while remounting"); > + sbi->s_mount_opt2 ^= EXT4_MOUNT2_NODAX; > + } > + > if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) > ext4_abort(sb, "Abort forced by user"); I'd just merge this with the check whether EXT4_MOUNT_DAX changed. Honza -- Jan Kara SUSE Labs, CR