From patchwork Wed Feb 17 03:34:16 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ross Zwisler X-Patchwork-Id: 8334091 Return-Path: X-Original-To: patchwork-linux-block@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 3C9D49FD6F for ; Wed, 17 Feb 2016 03:37:09 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7D6DB20256 for ; Wed, 17 Feb 2016 03:37:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7B75B202FF for ; Wed, 17 Feb 2016 03:37:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933169AbcBQDgs (ORCPT ); Tue, 16 Feb 2016 22:36:48 -0500 Received: from mga01.intel.com ([192.55.52.88]:7996 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965100AbcBQDfB (ORCPT ); Tue, 16 Feb 2016 22:35:01 -0500 Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP; 16 Feb 2016 19:34:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,458,1449561600"; d="scan'208";a="916486842" Received: from rzwisler-desk.amr.corp.intel.com (HELO phyrexia.intel.com) ([10.254.20.43]) by fmsmga002.fm.intel.com with ESMTP; 16 Feb 2016 19:34:37 -0800 From: Ross Zwisler To: linux-kernel@vger.kernel.org Cc: Ross Zwisler , "J. Bruce Fields" , "Theodore Ts'o" , Alexander Viro , Andreas Dilger , Andrew Morton , Dan Williams , Dave Chinner , Jan Kara , Jeff Layton , Jens Axboe , Matthew Wilcox , linux-block@vger.kernel.org, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@lists.01.org, xfs@oss.sgi.com Subject: [PATCH v3 3/6] ext4: Online defrag not supported with DAX Date: Tue, 16 Feb 2016 20:34:16 -0700 Message-Id: <1455680059-20126-4-git-send-email-ross.zwisler@linux.intel.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1455680059-20126-1-git-send-email-ross.zwisler@linux.intel.com> References: <1455680059-20126-1-git-send-email-ross.zwisler@linux.intel.com> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, 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 Online defrag operations for ext4 are hard coded to use the page cache. See ext4_ioctl() -> ext4_move_extents() -> move_extent_per_page() When combined with DAX I/O, which circumvents the page cache, this can result in data corruption. This was observed with xfstests ext4/307 and ext4/308. Fix this by only allowing online defrag for non-DAX files. Signed-off-by: Ross Zwisler Reviewed-by: Jan Kara --- fs/ext4/ioctl.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 0f6c369..e32c86f 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -583,6 +583,11 @@ group_extend_out: "Online defrag not supported with bigalloc"); err = -EOPNOTSUPP; goto mext_out; + } else if (IS_DAX(inode)) { + ext4_msg(sb, KERN_ERR, + "Online defrag not supported with DAX"); + err = -EOPNOTSUPP; + goto mext_out; } err = mnt_want_write_file(filp);