Merge tag 'for-5.8/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - The largest change for this cycle is the DM zoned target's metadata
   version 2 feature that adds support for pairing regular block devices
   with a zoned device to ease the performance impact associated with
   finite random zones of zoned device.

   The changes came in three batches: the first prepared for and then
   added the ability to pair a single regular block device, the second
   was a batch of fixes to improve zoned's reclaim heuristic, and the
   third removed the limitation of only adding a single additional
   regular block device to allow many devices.

   Testing has shown linear scaling as more devices are added.

 - Add new emulated block size (ebs) target that emulates a smaller
   logical_block_size than a block device supports

   The primary use-case is to emulate "512e" devices that have 512 byte
   logical_block_size and 4KB physical_block_size. This is useful to
   some legacy applications that otherwise wouldn't be able to be used
   on 4K devices because they depend on issuing IO in 512 byte
   granularity.

 - Add discard interfaces to DM bufio. First consumer of the interface
   is the dm-ebs target that makes heavy use of dm-bufio.

 - Fix DM crypt's block queue_limits stacking to not truncate
   logic_block_size.

 - Add Documentation for DM integrity's status line.

 - Switch DMDEBUG from a compile time config option to instead use
   dynamic debug via pr_debug.

 - Fix DM multipath target's hueristic for how it manages
   "queue_if_no_path" state internally.

   DM multipath now avoids disabling "queue_if_no_path" unless it is
   actually needed (e.g. in response to configure timeout or explicit
   "fail_if_no_path" message).

   This fixes reports of spurious -EIO being reported back to userspace
   application during fault tolerance testing with an NVMe backend.
   Added various dynamic DMDEBUG messages to assist with debugging
   queue_if_no_path in the future.

 - Add a new DM multipath "Historical Service Time" Path Selector.

 - Fix DM multipath's dm_blk_ioctl() to switch paths on IO error.

 - Improve DM writecache target performance by using explicit cache
   flushing for target's single-threaded usecase and a small cleanup to
   remove unnecessary test in persistent_memory_claim.

 - Other small cleanups in DM core, dm-persistent-data, and DM
   integrity.

* tag 'for-5.8/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (62 commits)
  dm crypt: avoid truncating the logical block size
  dm mpath: add DM device name to Failing/Reinstating path log messages
  dm mpath: enhance queue_if_no_path debugging
  dm mpath: restrict queue_if_no_path state machine
  dm mpath: simplify __must_push_back
  dm zoned: check superblock location
  dm zoned: prefer full zones for reclaim
  dm zoned: select reclaim zone based on device index
  dm zoned: allocate zone by device index
  dm zoned: support arbitrary number of devices
  dm zoned: move random and sequential zones into struct dmz_dev
  dm zoned: per-device reclaim
  dm zoned: add metadata pointer to struct dmz_dev
  dm zoned: add device pointer to struct dm_zone
  dm zoned: allocate temporary superblock for tertiary devices
  dm zoned: convert to xarray
  dm zoned: add a 'reserved' zone flag
  dm zoned: improve logging messages for reclaim
  dm zoned: avoid unnecessary device recalulation for secondary superblock
  dm zoned: add debugging message for reading superblocks
  ...

2 files changed, 15 insertions, 6 deletions

diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index af48d9da3916..8750f2dc5613 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -332,6 +332,8 @@ void *dm_per_bio_data(struct bio *bio, size_t data_size);
 struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size);
 unsigned dm_bio_get_target_bio_nr(const struct bio *bio);
 
+u64 dm_start_time_ns_from_clone(struct bio *bio);
+
 int dm_register_target(struct target_type *t);
 void dm_unregister_target(struct target_type *t);
 
@@ -557,13 +559,8 @@ void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
 #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__)
 #define DMINFO_LIMIT(fmt, ...) pr_info_ratelimited(DM_FMT(fmt), ##__VA_ARGS__)
 
-#ifdef CONFIG_DM_DEBUG
-#define DMDEBUG(fmt, ...) printk(KERN_DEBUG DM_FMT(fmt), ##__VA_ARGS__)
+#define DMDEBUG(fmt, ...) pr_debug(DM_FMT(fmt), ##__VA_ARGS__)
 #define DMDEBUG_LIMIT(fmt, ...) pr_debug_ratelimited(DM_FMT(fmt), ##__VA_ARGS__)
-#else
-#define DMDEBUG(fmt, ...) no_printk(fmt, ##__VA_ARGS__)
-#define DMDEBUG_LIMIT(fmt, ...) no_printk(fmt, ##__VA_ARGS__)
-#endif
 
 #define DMEMIT(x...) sz += ((sz >= maxlen) ? \
 			  0 : scnprintf(result + sz, maxlen - sz, x))
diff --git a/include/linux/dm-bufio.h b/include/linux/dm-bufio.h
index 3c8b7d274bd9..29d255fdd5d6 100644
--- a/include/linux/dm-bufio.h
+++ b/include/linux/dm-bufio.h
@@ -119,6 +119,11 @@ int dm_bufio_write_dirty_buffers(struct dm_bufio_client *c);
 int dm_bufio_issue_flush(struct dm_bufio_client *c);
 
 /*
+ * Send a discard request to the underlying device.
+ */
+int dm_bufio_issue_discard(struct dm_bufio_client *c, sector_t block, sector_t count);
+
+/*
  * Like dm_bufio_release but also move the buffer to the new
  * block. dm_bufio_write_dirty_buffers is needed to commit the new block.
  */
@@ -132,6 +137,13 @@ void dm_bufio_release_move(struct dm_buffer *b, sector_t new_block);
 void dm_bufio_forget(struct dm_bufio_client *c, sector_t block);
 
 /*
+ * Free the given range of buffers.
+ * This is just a hint, if the buffer is in use or dirty, this function
+ * does nothing.
+ */
+void dm_bufio_forget_buffers(struct dm_bufio_client *c, sector_t block, sector_t n_blocks);
+
+/*
  * Set the minimum number of buffers before cleanup happens.
  */
 void dm_bufio_set_minimum_buffers(struct dm_bufio_client *c, unsigned n);