From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ross Zwisler Subject: Re: [RFC 00/11] DAX fsynx/msync support Date: Thu, 29 Oct 2015 16:49:53 -0600 Message-ID: <20151029224953.GA17933@linux.intel.com> References: <1446149535-16200-1-git-send-email-ross.zwisler@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-kernel@vger.kernel.org, "H. Peter Anvin" , "J. Bruce Fields" , Theodore Ts'o , Alexander Viro , Andreas Dilger , Dan Williams , Dave Chinner , Ingo Molnar , Jan Kara , Jeff Layton , Matthew Wilcox , Thomas Gleixner , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@lists.01.org, x86@kernel.org, xfs@oss.sgi.com, Andrew Morton , Matthew Wilcox To: Ross Zwisler , Dave Chinner Return-path: Content-Disposition: inline In-Reply-To: <1446149535-16200-1-git-send-email-ross.zwisler@linux.intel.com> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Thu, Oct 29, 2015 at 02:12:04PM -0600, Ross Zwisler wrote: > This patch series adds support for fsync/msync to DAX. > > Patches 1 through 8 add various utilities that the DAX code will eventually > need, and the DAX code itself is added by patch 9. Patches 10 and 11 are > filesystem changes that are needed after the DAX code is added, but these > patches may change slightly as the filesystem fault handling for DAX is > being modified ([1] and [2]). > > I've marked this series as RFC because I'm still testing, but I wanted to > get this out there so people would see the direction I was going and > hopefully comment on any big red flags sooner rather than later. > > I realize that we are getting pretty dang close to the v4.4 merge window, > but I think that if we can get this reviewed and working it's a much better > solution than the "big hammer" approach that blindly flushes entire PMEM > namespaces [3]. > > [1] http://oss.sgi.com/archives/xfs/2015-10/msg00523.html > [2] http://marc.info/?l=linux-ext4&m=144550211312472&w=2 > [3] https://lists.01.org/pipermail/linux-nvdimm/2015-October/002614.html Hmm...I think I may need to isolate the fsync/msync flushing against races with truncate since we are calling into the filesystem directly with get_block(). Dave (Chinner), does this sound right? Also, one thing I forgot to mention is that these patches are built upon the first version of Dave Chinner's XFS patches and my ext2 patches that deal with the truncate races with DAX. A snapshot of my development tree with these patches applied can be found here: https://github.com/01org/prd/tree/fsync_rfc -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org