From patchwork Tue Sep 29 19:48:11 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 7289801 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 699F49F302 for ; Tue, 29 Sep 2015 19:53:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7DC42206F7 for ; Tue, 29 Sep 2015 19:53:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 93293206DC for ; Tue, 29 Sep 2015 19:53:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751552AbbI2Txz (ORCPT ); Tue, 29 Sep 2015 15:53:55 -0400 Received: from mga03.intel.com ([134.134.136.65]:58637 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751498AbbI2Txy (ORCPT ); Tue, 29 Sep 2015 15:53:54 -0400 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga103.jf.intel.com with ESMTP; 29 Sep 2015 12:53:54 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,609,1437462000"; d="scan'208";a="815710089" Received: from dwillia2-desk3.jf.intel.com ([10.54.39.39]) by orsmga002.jf.intel.com with ESMTP; 29 Sep 2015 12:53:54 -0700 Subject: [PATCH] ext2, ext4: warn when mounting with dax enabled From: Dan Williams To: ross.zwisler@linux.intel.com, david@fromorbit.com Cc: Theodore Ts'o , linux-nvdimm@lists.01.org, Andreas Dilger , Jan Kara , linux-fsdevel@vger.kernel.org, Matthew Wilcox , linux-ext4@vger.kernel.org, "Kirill A. Shutemov" Date: Tue, 29 Sep 2015 15:48:11 -0400 Message-ID: <20150929194806.5276.863.stgit@dwillia2-desk3.jf.intel.com> User-Agent: StGit/0.17.1-9-g687f MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Similar to XFS warn when mounting DAX while it is still considered under development. Also, aspects of the DAX implementation, for example synchronization against multiple faults and faults causing block allocation, depend on the correct implementation in the filesystem. The maturity of a given DAX implementation is filesystem specific. Cc: Jan Kara Cc: "Theodore Ts'o" Cc: Andreas Dilger Cc: Matthew Wilcox Cc: linux-ext4@vger.kernel.org Cc: Kirill A. Shutemov Reported-by: Dave Chinner Signed-off-by: Dan Williams Acked-by: Jan Kara --- Given the pending investigations [1], and rather than marking FS_DAX broken, warn about DAX usage until we've landed fixes for the issues that Dave has identified. [1]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002266.html fs/ext2/super.c | 2 ++ fs/ext4/super.c | 6 +++++- 2 files changed, 7 insertions(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 900e19cf9ef6..2597b0663bf2 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -566,6 +566,8 @@ static int parse_options(char *options, struct super_block *sb) /* Fall through */ case Opt_dax: #ifdef CONFIG_FS_DAX + ext2_msg(sb, KERN_WARNING, + "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); set_opt(sbi->s_mount_opt, DAX); #else ext2_msg(sb, KERN_INFO, "dax option not supported"); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index a63c7b0a10cf..4db6eb0b6979 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1656,8 +1656,12 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, } sbi->s_jquota_fmt = m->mount_opt; #endif -#ifndef CONFIG_FS_DAX } else if (token == Opt_dax) { +#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; +#else ext4_msg(sb, KERN_INFO, "dax option not supported"); return -1; #endif