From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752356AbcEARbU (ORCPT ); Sun, 1 May 2016 13:31:20 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:55330 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751087AbcEARbT (ORCPT ); Sun, 1 May 2016 13:31:19 -0400 Date: Sun, 1 May 2016 10:31:15 -0700 From: Christoph Hellwig To: Toshi Kani Cc: dan.j.williams@intel.com, david@fromorbit.com, jack@suse.cz, tytso@mit.edu, adilger.kernel@dilger.ca, ross.zwisler@linux.intel.com, linux-nvdimm@ml01.01.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/3] ext4: Add alignment check for DAX mount Message-ID: <20160501173115.GA21574@infradead.org> References: <1461962375-3720-1-git-send-email-toshi.kani@hpe.com> <1461962375-3720-2-git-send-email-toshi.kani@hpe.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1461962375-3720-2-git-send-email-toshi.kani@hpe.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 29, 2016 at 02:39:33PM -0600, Toshi Kani wrote: > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index 304c712..90a8670 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -3421,6 +3421,12 @@ static int ext4_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)) { > + ext4_msg(sb, KERN_ERR, > + "error: unaligned partition for dax"); > + goto failed_mount; > + } > if (!sb->s_bdev->bd_disk->fops->direct_access) { > ext4_msg(sb, KERN_ERR, > "error: device does not support dax"); Factor your new checks and the ->direct_access into a new helper. It should take the block device as file systems might have multiple underlying devices.