From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753513AbaJQHEN (ORCPT ); Fri, 17 Oct 2014 03:04:13 -0400 Received: from mga11.intel.com ([192.55.52.93]:52344 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753368AbaJQHCb (ORCPT ); Fri, 17 Oct 2014 03:02:31 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="401670930" Date: Thu, 16 Oct 2014 17:52:56 -0400 From: Matthew Wilcox To: Mathieu Desnoyers Cc: Matthew Wilcox , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v11 16/21] vfs,ext2: Remove CONFIG_EXT2_FS_XIP and rename CONFIG_FS_XIP to CONFIG_FS_DAX Message-ID: <20141016215256.GJ11522@wil.cx> References: <1411677218-29146-1-git-send-email-matthew.r.wilcox@intel.com> <1411677218-29146-17-git-send-email-matthew.r.wilcox@intel.com> <20141016122618.GN19075@thinkos.etherlink> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141016122618.GN19075@thinkos.etherlink> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 16, 2014 at 02:26:18PM +0200, Mathieu Desnoyers wrote: > > + bool "Direct Access support" > > + depends on MMU > > + help > > + Direct Access (DAX) can be used on memory-backed block devices. > > + If the block device supports DAX and the filesystem supports DAX, > > + then you can avoid using the pagecache to buffer I/Os. Turning > > + on this option will compile in support for DAX; you will need to > > + mount the filesystem using the -o xip option. > > There is a mismatch between the documentation file (earlier patch): -o > dax, and this config description: -o xip. Whoops! Good catch. > I guess we might want to switch the mount option to "-o dax" and > document it as such, and since it should be usable transparently for the > same use-cases "-o xip" was enabling, we might want to keep parsing of > "-o xip" in the code for backward compatibility. > > Thoughts ? That's exactly what we do for ext2. For ext4, we force people to use the new -o dax option. We stop documenting that -o xip exist, and we print a message to tell people to switch over to -o dax.