From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Darrick J. Wong" Subject: Re: [RFC PATCH 2/2] mm, fs: daxfile, an interface for byte-addressable updates to pmem Date: Thu, 22 Jun 2017 00:09:58 -0700 Message-ID: <20170622070958.GG3787@birch.djwong.org> References: <149766212410.22552.15957843500156182524.stgit@dwillia2-desk3.amr.corp.intel.com> <149766213493.22552.4057048843646200083.stgit@dwillia2-desk3.amr.corp.intel.com> <20170620052214.GA3787@birch.djwong.org> <20170620154255.GA2536@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20170620154255.GA2536@linux.intel.com> Sender: owner-linux-mm@kvack.org To: Ross Zwisler , Dan Williams , akpm@linux-foundation.org, Jan Kara , linux-nvdimm@lists.01.org, linux-api@vger.kernel.org, Dave Chinner , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Jeff Moyer , linux-fsdevel@vger.kernel.org, Christoph Hellwig , xfs List-Id: linux-api@vger.kernel.org On Tue, Jun 20, 2017 at 09:42:55AM -0600, Ross Zwisler wrote: > On Mon, Jun 19, 2017 at 10:22:14PM -0700, Darrick J. Wong wrote: > <> > > Fourth, the VFS entry points for things like read, write, truncate, > > utimes, fallocate, etc. all just bail out if S_IOMAP_FROZEN is set on a > > file, so that the block map cannot be modified. mmap is still allowed, > > as we've discussed. /Maybe/ we can allow fallocate to extend a file > > with zeroed extents (it will be slow) as I've heard murmurs about > > wanting to be able to extend a file, maybe not. > > Read and write should still be allowed, right? I had thought the usage model was pretty slanted towards mmap, but it's not a big deal to turn read/writes into glorified memcpy, provided we reject the io request if it goes past EOF. --D > -- > To unsubscribe from this list: send the line "unsubscribe linux-api" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- 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