From patchwork Mon Feb 22 18:59:20 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ross Zwisler X-Patchwork-Id: 8381921 Return-Path: X-Original-To: patchwork-linux-nvdimm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 54BB0C0553 for ; Mon, 22 Feb 2016 18:59:45 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8B2E22056D for ; Mon, 22 Feb 2016 18:59:44 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 857C52058A for ; Mon, 22 Feb 2016 18:59:43 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 6946C1A1F1D; Mon, 22 Feb 2016 10:59:45 -0800 (PST) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by ml01.01.org (Postfix) with ESMTP id E17751A1F1A for ; Mon, 22 Feb 2016 10:59:44 -0800 (PST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP; 22 Feb 2016 10:59:42 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,485,1449561600"; d="scan'208";a="657296596" Received: from rzwisler-desk.amr.corp.intel.com (HELO phyrexia.intel.com) ([10.254.181.157]) by FMSMGA003.fm.intel.com with ESMTP; 22 Feb 2016 10:59:42 -0800 From: Ross Zwisler To: linux-kernel@vger.kernel.org Subject: [PATCH v4 3/5] ext4: Online defrag not supported with DAX Date: Mon, 22 Feb 2016 11:59:20 -0700 Message-Id: <1456167562-28576-4-git-send-email-ross.zwisler@linux.intel.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1456167562-28576-1-git-send-email-ross.zwisler@linux.intel.com> References: <1456167562-28576-1-git-send-email-ross.zwisler@linux.intel.com> Cc: Jens Axboe , Theodore Ts'o , Andrew Morton , linux-nvdimm@lists.01.org, Dave Chinner , xfs@oss.sgi.com, linux-block@vger.kernel.org, linux-mm@kvack.org, Andreas Dilger , Alexander Viro , Jan Kara , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, 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 a99b010..eae5917 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);