Merge tag 'for-4.12/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - A major update for DM cache that reduces the latency for deciding
   whether blocks should migrate to/from the cache. The bio-prison-v2
   interface supports this improvement by enabling direct dispatch of
   work to workqueues rather than having to delay the actual work
   dispatch to the DM cache core. So the dm-cache policies are much more
   nimble by being able to drive IO as they see fit. One immediate
   benefit from the improved latency is a cache that should be much more
   adaptive to changing workloads.

 - Add a new DM integrity target that emulates a block device that has
   additional per-sector tags that can be used for storing integrity
   information.

 - Add a new authenticated encryption feature to the DM crypt target
   that builds on the capabilities provided by the DM integrity target.

 - Add MD interface for switching the raid4/5/6 journal mode and update
   the DM raid target to use it to enable aid4/5/6 journal write-back
   support.

 - Switch the DM verity target over to using the asynchronous hash
   crypto API (this helps work better with architectures that have
   access to off-CPU algorithm providers, which should reduce CPU
   utilization).

 - Various request-based DM and DM multipath fixes and improvements from
   Bart and Christoph.

 - A DM thinp target fix for a bio structure leak that occurs for each
   discard IFF discard passdown is enabled.

 - A fix for a possible deadlock in DM bufio and a fix to re-check the
   new buffer allocation watermark in the face of competing admin
   changes to the 'max_cache_size_bytes' tunable.

 - A couple DM core cleanups.

* tag 'for-4.12/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (50 commits)
  dm bufio: check new buffer allocation watermark every 30 seconds
  dm bufio: avoid a possible ABBA deadlock
  dm mpath: make it easier to detect unintended I/O request flushes
  dm mpath: cleanup QUEUE_IF_NO_PATH bit manipulation by introducing assign_bit()
  dm mpath: micro-optimize the hot path relative to MPATHF_QUEUE_IF_NO_PATH
  dm: introduce enum dm_queue_mode to cleanup related code
  dm mpath: verify __pg_init_all_paths locking assumptions at runtime
  dm: verify suspend_locking assumptions at runtime
  dm block manager: remove an unused argument from dm_block_manager_create()
  dm rq: check blk_mq_register_dev() return value in dm_mq_init_request_queue()
  dm mpath: delay requeuing while path initialization is in progress
  dm mpath: avoid that path removal can trigger an infinite loop
  dm mpath: split and rename activate_path() to prepare for its expanded use
  dm ioctl: prevent stack leak in dm ioctl call
  dm integrity: use previously calculated log2 of sectors_per_block
  dm integrity: use hex2bin instead of open-coded variant
  dm crypt: replace custom implementation of hex2bin()
  dm crypt: remove obsolete references to per-CPU state
  dm verity: switch to using asynchronous hash crypto API
  dm crypt: use WQ_HIGHPRI for the IO and crypt workqueues
  ...

1 files changed, 20 insertions, 6 deletions

diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index c7ea33e38fb9..925b63cdef52 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -22,11 +22,13 @@ struct bio_vec;
 /*
  * Type of table, mapped_device's mempool and request_queue
  */
-#define DM_TYPE_NONE			0
-#define DM_TYPE_BIO_BASED		1
-#define DM_TYPE_REQUEST_BASED		2
-#define DM_TYPE_MQ_REQUEST_BASED	3
-#define DM_TYPE_DAX_BIO_BASED		4
+enum dm_queue_mode {
+	DM_TYPE_NONE		 = 0,
+	DM_TYPE_BIO_BASED	 = 1,
+	DM_TYPE_REQUEST_BASED	 = 2,
+	DM_TYPE_MQ_REQUEST_BASED = 3,
+	DM_TYPE_DAX_BIO_BASED	 = 4,
+};
 
 typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
 
@@ -221,6 +223,18 @@ struct target_type {
  */
 typedef unsigned (*dm_num_write_bios_fn) (struct dm_target *ti, struct bio *bio);
 
+/*
+ * A target implements own bio data integrity.
+ */
+#define DM_TARGET_INTEGRITY		0x00000010
+#define dm_target_has_integrity(type)	((type)->features & DM_TARGET_INTEGRITY)
+
+/*
+ * A target passes integrity data to the lower device.
+ */
+#define DM_TARGET_PASSES_INTEGRITY	0x00000020
+#define dm_target_passes_integrity(type) ((type)->features & DM_TARGET_PASSES_INTEGRITY)
+
 struct dm_target {
 	struct dm_table *table;
 	struct target_type *type;
@@ -465,7 +479,7 @@ void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callback
  * Useful for "hybrid" target (supports both bio-based
  * and request-based).
  */
-void dm_table_set_type(struct dm_table *t, unsigned type);
+void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type);
 
 /*
  * Finally call this to make the table ready for use.