From: Eric Sandeen Subject: Re: [PATCH 0/9] add ext4 per-inode DAX flag Date: Tue, 5 Sep 2017 21:12:35 -0500 Message-ID: References: <20170905223541.20594-1-ross.zwisler@linux.intel.com> Reply-To: sandeen-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Theodore Ts'o , "Darrick J. Wong" , linux-nvdimm-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org, Dave Chinner , linux-xfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Andreas Dilger , Jan Kara , linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Christoph Hellwig To: Ross Zwisler , Andrew Morton , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Return-path: In-Reply-To: <20170905223541.20594-1-ross.zwisler-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" List-Id: linux-ext4.vger.kernel.org On 9/5/17 5:35 PM, Ross Zwisler wrote: > The original intent of this series was to add a per-inode DAX flag to ext4 > so that it would be consistent with XFS. In my travels I found and fixed > several related issues in both ext4 and XFS. Hi Ross - hch had a lot of reasons to nuke the dax flag from orbit, and we just /disabled/ it in xfs due to its habit of crashing the kernel... so a couple questions: 1) does this series pass hch's "test the per-inode DAX flag" fstest? 2) do we have an agreement that we need this flag at all, or is this just a parity item because xfs has^whad a per-inode flag? Thanks, -Eric > I'm not fully happy with the ways that ext4 DAX interacts with conflicting > features (journaling, inline data and encryption). My goal with this > series was to make all these interactions as consistent as possilble, and > of course to make them safe. If anyone has ideas for improvements, I'm > very open. > > Ross Zwisler (9): > ext4: remove duplicate extended attributes defs > xfs: always use DAX if mount option is used > xfs: validate bdev support for DAX inode flag > ext4: add ext4_should_use_dax() > ext4: ext4_change_inode_journal_flag error handling > ext4: safely transition S_DAX on journaling changes > ext4: prevent data corruption with inline data + DAX > ext4: add sanity check for encryption + DAX > ext4: add per-inode DAX flag > > fs/ext4/ext4.h | 47 ++++++--------------------------------------- > fs/ext4/ext4_jbd2.h | 16 ++++++++++++++++ > fs/ext4/inline.c | 10 ---------- > fs/ext4/inode.c | 45 ++++++++++++++++++++++++------------------- > fs/ext4/ioctl.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++-- > fs/ext4/super.c | 8 ++++++++ > fs/xfs/xfs_ioctl.c | 14 +++++++++++--- > 7 files changed, 119 insertions(+), 76 deletions(-) >