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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 451DAC433E0 for ; Fri, 15 May 2020 03:39:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1BA5320671 for ; Fri, 15 May 2020 03:39:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728373AbgEODjA (ORCPT ); Thu, 14 May 2020 23:39:00 -0400 Received: from mga06.intel.com ([134.134.136.31]:46650 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726176AbgEODi7 (ORCPT ); Thu, 14 May 2020 23:38:59 -0400 IronPort-SDR: fY68yZquNQDbS2A827prcLANqkwVChvpdZKEXUa/e7eTybr74/blePQGMbDkyvdj9O9CfD4jsd RvcW6JPkd+/A== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 May 2020 20:38:58 -0700 IronPort-SDR: T4cM1uZ2flAItzX+MQz5ei98EtCAdtIwnVbjhkmIoV0zLm0ze9GZnWDMsuNauIFg2+EpfK9OwF myEPk3r620BA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,393,1583222400"; d="scan'208";a="372565874" Received: from iweiny-desk2.sc.intel.com ([10.3.52.147]) by fmsmga001.fm.intel.com with ESMTP; 14 May 2020 20:38:58 -0700 Date: Thu, 14 May 2020 20:38:58 -0700 From: Ira Weiny To: "Darrick J. Wong" Cc: linux-ext4@vger.kernel.org, Andreas Dilger , "Theodore Y. Ts'o" , Jan Kara , Al Viro , Dan Williams , Dave Chinner , Christoph Hellwig , Jeff Moyer , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V1 7/9] fs/ext4: Make DAX mount option a tri-state Message-ID: <20200515033858.GE2140786@iweiny-DESK2.sc.intel.com> References: <20200514065316.2500078-1-ira.weiny@intel.com> <20200514065316.2500078-8-ira.weiny@intel.com> <20200514150839.GB2077014@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200514150839.GB2077014@magnolia> User-Agent: Mutt/1.11.1 (2018-12-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 14, 2020 at 08:08:39AM -0700, Darrick J. Wong wrote: > On Wed, May 13, 2020 at 11:53:13PM -0700, 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_MOUNT2_DAX_NEVER and set > > it and EXT4_MOUNT_DAX_ALWAYS appropriately. > > > > We also force EXT4_MOUNT2_DAX_NEVER if !CONFIG_FS_DAX. > > > > https://lore.kernel.org/lkml/20200405061945.GA94792@iweiny-DESK2.sc.intel.com/ > > > > Signed-off-by: Ira Weiny > > > > --- > > Changes from RFC: > > Combine remount check for DAX_NEVER with DAX_ALWAYS > > Update ext4_should_enable_dax() > > --- > > fs/ext4/ext4.h | 1 + > > fs/ext4/inode.c | 2 ++ > > fs/ext4/super.c | 43 +++++++++++++++++++++++++++++++++++++------ > > 3 files changed, 40 insertions(+), 6 deletions(-) > > > > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > > index 86a0994332ce..01d1de838896 100644 > > --- a/fs/ext4/ext4.h > > +++ b/fs/ext4/ext4.h > > @@ -1168,6 +1168,7 @@ struct ext4_inode_info { > > blocks */ > > #define EXT4_MOUNT2_HURD_COMPAT 0x00000004 /* Support HURD-castrated > > file systems */ > > +#define EXT4_MOUNT2_DAX_NEVER 0x00000008 /* Do not allow Direct Access */ > > > > #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM 0x00000008 /* User explicitly > > specified journal checksum */ > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > > index 23e42a223235..140b1930e2f4 100644 > > --- a/fs/ext4/inode.c > > +++ b/fs/ext4/inode.c > > @@ -4400,6 +4400,8 @@ int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) > > > > static bool ext4_should_enable_dax(struct inode *inode) > > { > > + if (test_opt2(inode->i_sb, DAX_NEVER)) > > + return false; > > if (!S_ISREG(inode->i_mode)) > > return false; > > if (ext4_should_journal_data(inode)) > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > > index 5ec900fdf73c..e01a040a58a9 100644 > > --- a/fs/ext4/super.c > > +++ b/fs/ext4/super.c > > @@ -1505,6 +1505,7 @@ enum { > > Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota, > > Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err, > > Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax, > > + Opt_dax_str, > > Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error, > > Opt_nowarn_on_error, Opt_mblk_io_submit, > > Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize, > > @@ -1570,6 +1571,7 @@ static const match_table_t tokens = { > > {Opt_barrier, "barrier"}, > > {Opt_nobarrier, "nobarrier"}, > > {Opt_i_version, "i_version"}, > > + {Opt_dax_str, "dax=%s"}, > > {Opt_dax, "dax"}, > > {Opt_stripe, "stripe=%u"}, > > {Opt_delalloc, "delalloc"}, > > @@ -1767,6 +1769,7 @@ static const struct mount_opts { > > {Opt_min_batch_time, 0, MOPT_GTE0}, > > {Opt_inode_readahead_blks, 0, MOPT_GTE0}, > > {Opt_init_itable, 0, MOPT_GTE0}, > > + {Opt_dax_str, 0, MOPT_STRING}, > > {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET}, > > {Opt_stripe, 0, MOPT_GTE0}, > > {Opt_resuid, 0, MOPT_GTE0}, > > @@ -2076,13 +2079,32 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, > > } > > sbi->s_jquota_fmt = m->mount_opt; > > #endif > > - } else if (token == Opt_dax) { > > + } else if (token == Opt_dax || token == Opt_dax_str) { > > #ifdef CONFIG_FS_DAX > > - ext4_msg(sb, KERN_WARNING, > > - "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); > > - sbi->s_mount_opt |= m->mount_opt; > > + char *tmp = match_strdup(&args[0]); > > + > > + if (!tmp || !strcmp(tmp, "always")) { > > + ext4_msg(sb, KERN_WARNING, > > + "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); > > + sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS; > > + sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER; > > + } else if (!strcmp(tmp, "never")) { > > + sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER; > > + sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS; > > + } else if (!strcmp(tmp, "inode")) { > > + sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS; > > + sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER; > > + } else { > > + ext4_msg(sb, KERN_WARNING, "DAX invalid option."); > > + kfree(tmp); > > + return -1; > > + } > > + > > + kfree(tmp); > > #else > > ext4_msg(sb, KERN_INFO, "dax option not supported"); > > + sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER; > > + sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS; > > return -1; > > #endif > > } else if (token == Opt_data_err_abort) { > > @@ -2306,6 +2328,13 @@ 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, DAX_NEVER)) > > + SEQ_OPTS_PUTS("dax=never"); > > + else if (test_opt(sb, DAX_ALWAYS)) > > + SEQ_OPTS_PUTS("dax=always"); > > + else > > + SEQ_OPTS_PUTS("dax=inode"); > > dax=inode is the default; do you need to show it? > > (Especially since xfs doesn't...) I'll only show it if -o dax or -o dax=inode was actually specified per earlier comments regarding ext4 behavior. Ira > > --D > > > + > > ext4_show_quota_options(seq, sb); > > return 0; > > } > > @@ -5425,10 +5454,12 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) > > goto restore_opts; > > } > > > > - if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX_ALWAYS) { > > + if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX_ALWAYS || > > + (sbi->s_mount_opt2 ^ old_opts.s_mount_opt2) & EXT4_MOUNT2_DAX_NEVER) { > > ext4_msg(sb, KERN_WARNING, "warning: refusing change of " > > - "dax flag with busy inodes while remounting"); > > + "dax mount option with busy inodes while remounting"); > > sbi->s_mount_opt ^= EXT4_MOUNT_DAX_ALWAYS; > > + sbi->s_mount_opt2 ^= EXT4_MOUNT2_DAX_NEVER; > > } > > > > if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) > > -- > > 2.25.1 > >