Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753181AbcD2Usy (ORCPT ); Fri, 29 Apr 2016 16:48:54 -0400 Received: from g1t5425.austin.hp.com ([15.216.225.55]:40046 "EHLO g1t5425.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753023AbcD2Us3 (ORCPT ); Fri, 29 Apr 2016 16:48:29 -0400 From: Toshi Kani To: dan.j.williams@intel.com, david@fromorbit.com, jack@suse.cz Cc: tytso@mit.edu, adilger.kernel@dilger.ca, ross.zwisler@linux.intel.com, toshi.kani@hpe.com, linux-nvdimm@ml01.01.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/3] ext2: Add alignment check for DAX mount Date: Fri, 29 Apr 2016 14:39:34 -0600 Message-Id: <1461962375-3720-3-git-send-email-toshi.kani@hpe.com> X-Mailer: git-send-email 2.5.5 In-Reply-To: <1461962375-3720-1-git-send-email-toshi.kani@hpe.com> References: <1461962375-3720-1-git-send-email-toshi.kani@hpe.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1085 Lines: 31 When a partition is not aligned by 4KB, mount -o dax succeeds, but any read/write access to the filesystem fails, except for metadata update. Add alignment check to ext2_fill_super() when -o dax is specified. Signed-off-by: Toshi Kani Cc: Jan Kara Cc: Dan Williams Cc: Ross Zwisler --- fs/ext2/super.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/ext2/super.c b/fs/ext2/super.c index b78caf2..34e32d9 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -927,6 +927,12 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) "error: unsupported blocksize for dax"); goto failed_mount; } + if (sb->s_bdev->bd_part->start_sect % (PAGE_SIZE / 512) || + sb->s_bdev->bd_part->nr_sects % (PAGE_SIZE / 512)) { + ext2_msg(sb, KERN_ERR, + "error: unaligned partition for dax"); + goto failed_mount; + } if (!sb->s_bdev->bd_disk->fops->direct_access) { ext2_msg(sb, KERN_ERR, "error: device does not support dax");