Merge tag 'for-4.15/dm' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - a few conversions from atomic_t to ref_count_t

 - a DM core fix for a race during device destruction that could result
   in a BUG_ON

 - a stable@ fix for a DM cache race condition that could lead to data
   corruption when operating in writeback mode (writethrough is default)

 - various DM cache cleanups and improvements

 - add DAX support to the DM log-writes target

 - a fix for the DM zoned target's ability to deal with the last zone of
   the drive being smaller than all others

 - a stable@ DM crypt and DM integrity fix for a negative check that was
   to restrictive (prevented slab debug with XFS ontop of DM crypt from
   working)

 - a DM raid target fix for a panic that can occur when forcing a raid
   to sync

* tag 'for-4.15/dm' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (25 commits)
  dm cache: lift common migration preparation code to alloc_migration()
  dm cache: remove usused deferred_cells member from struct cache
  dm cache policy smq: allocate cache blocks in order
  dm cache policy smq: change max background work from 10240 to 4096 blocks
  dm cache background tracker: limit amount of background work that may be issued at once
  dm cache policy smq: take origin idle status into account when queuing writebacks
  dm cache policy smq: handle races with queuing background_work
  dm raid: fix panic when attempting to force a raid to sync
  dm integrity: allow unaligned bv_offset
  dm crypt: allow unaligned bv_offset
  dm: small cleanup in dm_get_md()
  dm: fix race between dm_get_from_kobject() and __dm_destroy()
  dm: allocate struct mapped_device with kvzalloc
  dm zoned: ignore last smaller runt zone
  dm space map metadata: use ARRAY_SIZE
  dm log writes: add support for DAX
  dm log writes: add support for inline data buffers
  dm cache: simplify get_per_bio_data() by removing data_size argument
  dm cache: remove all obsolete writethrough-specific code
  dm cache: submit writethrough writes in parallel to origin and cache
  ...

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 38c84c0a35d4..36399bb875dd 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -19,6 +19,7 @@
 #include <linux/hdreg.h>
 #include <linux/completion.h>
 #include <linux/kobject.h>
+#include <linux/refcount.h>
 
 #include "dm-stats.h"
 
@@ -38,7 +39,7 @@
  */
 struct dm_dev_internal {
 	struct list_head list;
-	atomic_t count;
+	refcount_t count;
 	struct dm_dev *dm_dev;
 };