From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:48516 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389851AbeGJSgb (ORCPT ); Tue, 10 Jul 2018 14:36:31 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ross Zwisler , Dan Williams , Toshi Kani , Mike Snitzer Subject: [PATCH 4.17 50/56] dm: prevent DAX mounts if not supported Date: Tue, 10 Jul 2018 20:25:32 +0200 Message-Id: <20180710182505.930174457@linuxfoundation.org> In-Reply-To: <20180710182503.544433950@linuxfoundation.org> References: <20180710182503.544433950@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ross Zwisler commit dbc626597c39b24cefce09fbd8e9dea85869a801 upstream. Currently device_supports_dax() just checks to see if the QUEUE_FLAG_DAX flag is set on the device's request queue to decide whether or not the device supports filesystem DAX. Really we should be using bdev_dax_supported() like filesystems do at mount time. This performs other tests like checking to make sure the dax_direct_access() path works. We also explicitly clear QUEUE_FLAG_DAX on the DM device's request queue if any of the underlying devices do not support DAX. This makes the handling of QUEUE_FLAG_DAX consistent with the setting/clearing of most other flags in dm_table_set_restrictions(). Now that bdev_dax_supported() explicitly checks for QUEUE_FLAG_DAX, this will ensure that filesystems built upon DM devices will only be able to mount with DAX if all underlying devices also support DAX. Signed-off-by: Ross Zwisler Fixes: commit 545ed20e6df6 ("dm: add infrastructure for DAX support") Cc: stable@vger.kernel.org Acked-by: Dan Williams Reviewed-by: Toshi Kani Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-table.c | 7 ++++--- drivers/md/dm.c | 3 +-- 2 files changed, 5 insertions(+), 5 deletions(-) --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -885,9 +885,7 @@ EXPORT_SYMBOL_GPL(dm_table_set_type); static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, sector_t start, sector_t len, void *data) { - struct request_queue *q = bdev_get_queue(dev->bdev); - - return q && blk_queue_dax(q); + return bdev_dax_supported(dev->bdev, PAGE_SIZE); } static bool dm_table_supports_dax(struct dm_table *t) @@ -1907,6 +1905,9 @@ void dm_table_set_restrictions(struct dm if (dm_table_supports_dax(t)) blk_queue_flag_set(QUEUE_FLAG_DAX, q); + else + blk_queue_flag_clear(QUEUE_FLAG_DAX, q); + if (dm_table_supports_dax_write_cache(t)) dax_write_cache(t->md->dax_dev, true); --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1056,8 +1056,7 @@ static long dm_dax_direct_access(struct if (len < 1) goto out; nr_pages = min(len, nr_pages); - if (ti->type->direct_access) - ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn); + ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn); out: dm_put_live_table(md, srcu_idx);