Merge tag 'for-5.6/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Fix DM core's potential for q->make_request_fn NULL pointer in the
   unlikely case that a DM device is created without a DM table and then
   accessed due to upper-layer userspace code or user error.

 - Fix DM thin-provisioning's metadata_pre_commit_callback to not use
   memory after it is free'd. Also refactor code to disallow changing
   the thin-pool's data device once in use -- doing so guarantees smae
   lifetime of pool's data device relative to the pool metadata.

 - Fix DM space maps used by DM thinp and DM cache to avoid reuse of a
   already used block. This race was identified with extremely heavy
   snapshot use in the context of DM thin provisioning.

 - Fix DM raid's table status relative to an active rebuild.

 - Fix DM crypt to use GFP_NOIO rather than GFP_NOFS in call to
   skcipher_request_alloc(). Also fix benbi IV constructor crash if used
   in authenticated mode.

 - Add DM crypt support for Elephant diffuser to allow for Bitlocker
   compatibility.

 - Fix DM verity target to not prefetch hash blocks for data that has
   already been verified.

 - Fix DM writecache's incorrect flush sequence during commit when in
   SSD mode.

 - Improve DM writecache's sequential write performance on SSDs.

 - Add DM zoned target support for zone sizes smaller than 128MiB.

 - Add DM multipath 'queue_if_no_path_timeout_secs' module param to
   allow timeout if path isn't reinstated. This allows users a kernel
   safety-net against IO hanging indefinitely, due to no active paths,
   that has historically only been provided by multipathd userspace.

 - Various DM code cleanups to use true/false rather than 1/0, a
   variable rename in dm-dust, and fix for a math error in comment for
   DM thin metadata's ondisk format.

* tag 'for-5.6/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (21 commits)
  dm: fix potential for q->make_request_fn NULL pointer
  dm writecache: improve performance of large linear writes on SSDs
  dm mpath: Add timeout mechanism for queue_if_no_path
  dm thin: change data device's flush_bio to be member of struct pool
  dm thin: don't allow changing data device during thin-pool reload
  dm thin: fix use-after-free in metadata_pre_commit_callback
  dm thin metadata: use pool locking at end of dm_pool_metadata_close
  dm writecache: fix incorrect flush sequence when doing SSD mode commit
  dm crypt: fix benbi IV constructor crash if used in authenticated mode
  dm crypt: Implement Elephant diffuser for Bitlocker compatibility
  dm space map common: fix to ensure new block isn't already in use
  dm verity: don't prefetch hash blocks for already-verified data
  dm crypt: fix GFP flags passed to skcipher_request_alloc()
  dm thin metadata: Fix trivial math error in on-disk format documentation
  dm thin metadata: use true/false for bool variable
  dm snapshot: use true/false for bool variable
  dm bio prison v2: use true/false for bool variable
  dm mpath: use true/false for bool variable
  dm zoned: support zone sizes smaller than 128MiB
  dm raid: table line rebuild status fixes
  ...

1 files changed, 12 insertions, 10 deletions

diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c
index b88d6d701f5b..fc9947d6210c 100644
--- a/drivers/md/dm-thin-metadata.c
+++ b/drivers/md/dm-thin-metadata.c
@@ -28,7 +28,7 @@
  *
  * - A hierarchical btree, with 2 levels which effectively maps (thin
  *   dev id, virtual block) -> block_time.  Block time is a 64-bit
- *   field holding the time in the low 24 bits, and block in the top 48
+ *   field holding the time in the low 24 bits, and block in the top 40
  *   bits.
  *
  * BTrees consist solely of btree_nodes, that fill a block.  Some are
@@ -387,16 +387,15 @@ static int subtree_equal(void *context, const void *value1_le, const void *value
  * Variant that is used for in-core only changes or code that
  * shouldn't put the pool in service on its own (e.g. commit).
  */
-static inline void __pmd_write_lock(struct dm_pool_metadata *pmd)
+static inline void pmd_write_lock_in_core(struct dm_pool_metadata *pmd)
 	__acquires(pmd->root_lock)
 {
 	down_write(&pmd->root_lock);
 }
-#define pmd_write_lock_in_core(pmd) __pmd_write_lock((pmd))
 
 static inline void pmd_write_lock(struct dm_pool_metadata *pmd)
 {
-	__pmd_write_lock(pmd);
+	pmd_write_lock_in_core(pmd);
 	if (unlikely(!pmd->in_service))
 		pmd->in_service = true;
 }
@@ -811,7 +810,7 @@ static int __write_changed_details(struct dm_pool_metadata *pmd)
 			return r;
 
 		if (td->open_count)
-			td->changed = 0;
+			td->changed = false;
 		else {
 			list_del(&td->list);
 			kfree(td);
@@ -831,6 +830,7 @@ static int __commit_transaction(struct dm_pool_metadata *pmd)
 	 * We need to know if the thin_disk_superblock exceeds a 512-byte sector.
 	 */
 	BUILD_BUG_ON(sizeof(struct thin_disk_superblock) > 512);
+	BUG_ON(!rwsem_is_locked(&pmd->root_lock));
 
 	if (unlikely(!pmd->in_service))
 		return 0;
@@ -953,6 +953,7 @@ int dm_pool_metadata_close(struct dm_pool_metadata *pmd)
 		return -EBUSY;
 	}
 
+	pmd_write_lock_in_core(pmd);
 	if (!dm_bm_is_read_only(pmd->bm) && !pmd->fail_io) {
 		r = __commit_transaction(pmd);
 		if (r < 0)
@@ -961,6 +962,7 @@ int dm_pool_metadata_close(struct dm_pool_metadata *pmd)
 	}
 	if (!pmd->fail_io)
 		__destroy_persistent_data_objects(pmd);
+	pmd_write_unlock(pmd);
 
 	kfree(pmd);
 	return 0;
@@ -1106,7 +1108,7 @@ static int __set_snapshot_details(struct dm_pool_metadata *pmd,
 	if (r)
 		return r;
 
-	td->changed = 1;
+	td->changed = true;
 	td->snapshotted_time = time;
 
 	snap->mapped_blocks = td->mapped_blocks;
@@ -1618,7 +1620,7 @@ static int __insert(struct dm_thin_device *td, dm_block_t block,
 	if (r)
 		return r;
 
-	td->changed = 1;
+	td->changed = true;
 	if (inserted)
 		td->mapped_blocks++;
 
@@ -1649,7 +1651,7 @@ static int __remove(struct dm_thin_device *td, dm_block_t block)
 		return r;
 
 	td->mapped_blocks--;
-	td->changed = 1;
+	td->changed = true;
 
 	return 0;
 }
@@ -1703,7 +1705,7 @@ static int __remove_range(struct dm_thin_device *td, dm_block_t begin, dm_block_
 	}
 
 	td->mapped_blocks -= total_count;
-	td->changed = 1;
+	td->changed = true;
 
 	/*
 	 * Reinsert the mapping tree.
@@ -1841,7 +1843,7 @@ int dm_pool_commit_metadata(struct dm_pool_metadata *pmd)
 	 * Care is taken to not have commit be what
 	 * triggers putting the thin-pool in-service.
 	 */
-	__pmd_write_lock(pmd);
+	pmd_write_lock_in_core(pmd);
 	if (pmd->fail_io)
 		goto out;