Merge tag 'for-6.4/dm-changes' of...

Merge tag 'for-6.4/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Split dm-bufio's rw_semaphore and rbtree. Offers improvements to
   dm-bufio's locking to allow increased concurrent IO -- particularly
   for read access for buffers already in dm-bufio's cache.

 - Also split dm-bio-prison-v1's spinlock and rbtree with comparable aim
   at improving concurrent IO (for the DM thinp target).

 - Both the dm-bufio and dm-bio-prison-v1 scaling of the number of locks
   and rbtrees used are managed by dm_num_hash_locks(). And the hash
   function used by both is dm_hash_locks_index().

 - Allow DM targets to require DISCARD, WRITE_ZEROES and SECURE_ERASE to
   be split at the target specified boundary (in terms of
   max_discard_sectors, max_write_zeroes_sectors and
   max_secure_erase_sectors respectively).

 - DM verity error handling fix for check_at_most_once on FEC.

 - Update DM verity target to emit audit events on verification failure
   and more.

 - DM core ->io_hints improvements needed in support of new discard
   support that is added to the DM "zero" and "error" targets.

 - Fix missing kmem_cache_destroy() call in initialization error path of
   both the DM integrity and DM clone targets.

 - A couple fixes for DM flakey, also add "error_reads" feature.

 - Fix DM core's resume to not lock FS when the DM map is NULL;
   otherwise initial table load can race with FS mount that takes
   superblock's ->s_umount rw_semaphore.

 - Various small improvements to both DM core and DM targets.

* tag 'for-6.4/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (40 commits)
  dm: don't lock fs when the map is NULL in process of resume
  dm flakey: add an "error_reads" option
  dm flakey: remove trailing space in the table line
  dm flakey: fix a crash with invalid table line
  dm ioctl: fix nested locking in table_clear() to remove deadlock concern
  dm: unexport dm_get_queue_limits()
  dm: allow targets to require splitting WRITE_ZEROES and SECURE_ERASE
  dm: add helper macro for simple DM target module init and exit
  dm raid: remove unused d variable
  dm: remove unnecessary (void*) conversions
  dm mirror: add DMERR message if alloc_workqueue fails
  dm: push error reporting down to dm_register_target()
  dm integrity: call kmem_cache_destroy() in dm_integrity_init() error path
  dm clone: call kmem_cache_destroy() in dm_clone_init() error path
  dm error: add discard support
  dm zero: add discard support
  dm table: allow targets without devices to set ->io_hints
  dm verity: emit audit events on verification failure and more
  dm verity: fix error handling for check_at_most_once on FEC
  dm: improve hash_locks sizing and hash function
  ...

Documentation/admin-guide/device-mapper/dm-flakey.rst

@@ -39,6 +39,10 @@ Optional feature parameters:
   If no feature parameters are present, during the periods of
   unreliability, all I/O returns errors.
 
+  error_reads:
+	All read I/O is failed with an error signalled.
+	Write I/O is handled correctly.
+
   drop_writes:
 	All write I/O is silently ignored.
 	Read I/O is handled correctly.

drivers/md/dm-bio-prison-v1.c

@@ -18,10 +18,15 @@
 
 #define MIN_CELLS 1024
 
-struct dm_bio_prison {
+struct prison_region {
 	spinlock_t lock;
-	struct rb_root cells;
+	struct rb_root cell;
+} ____cacheline_aligned_in_smp;
+
+struct dm_bio_prison {
 	mempool_t cell_pool;
+	unsigned int num_locks;
+	struct prison_region regions[];
 };
 
 static struct kmem_cache *_cell_cache;
@@ -34,13 +39,20 @@ static struct kmem_cache *_cell_cache;
  */
 struct dm_bio_prison *dm_bio_prison_create(void)
 {
-	struct dm_bio_prison *prison = kzalloc(sizeof(*prison), GFP_KERNEL);
 	int ret;
+	unsigned int i, num_locks;
+	struct dm_bio_prison *prison;
 
+	num_locks = dm_num_hash_locks();
+	prison = kzalloc(struct_size(prison, regions, num_locks), GFP_KERNEL);
 	if (!prison)
 		return NULL;
+	prison->num_locks = num_locks;
 
-	spin_lock_init(&prison->lock);
+	for (i = 0; i < prison->num_locks; i++) {
+		spin_lock_init(&prison->regions[i].lock);
+		prison->regions[i].cell = RB_ROOT;
+	}
 
 	ret = mempool_init_slab_pool(&prison->cell_pool, MIN_CELLS, _cell_cache);
 	if (ret) {
@@ -48,8 +60,6 @@ struct dm_bio_prison *dm_bio_prison_create(void)
 		return NULL;
 	}
 
-	prison->cells = RB_ROOT;
-
 	return prison;
 }
 EXPORT_SYMBOL_GPL(dm_bio_prison_create);
@@ -107,14 +117,32 @@ static int cmp_keys(struct dm_cell_key *lhs,
 	return 0;
 }
 
-static int __bio_detain(struct dm_bio_prison *prison,
+static inline unsigned int lock_nr(struct dm_cell_key *key, unsigned int num_locks)
+{
+	return dm_hash_locks_index((key->block_begin >> BIO_PRISON_MAX_RANGE_SHIFT),
+				   num_locks);
+}
+
+bool dm_cell_key_has_valid_range(struct dm_cell_key *key)
+{
+	if (WARN_ON_ONCE(key->block_end - key->block_begin > BIO_PRISON_MAX_RANGE))
+		return false;
+	if (WARN_ON_ONCE((key->block_begin >> BIO_PRISON_MAX_RANGE_SHIFT) !=
+			 (key->block_end - 1) >> BIO_PRISON_MAX_RANGE_SHIFT))
+		return false;
+
+	return true;
+}
+EXPORT_SYMBOL(dm_cell_key_has_valid_range);
+
+static int __bio_detain(struct rb_root *root,
 			struct dm_cell_key *key,
 			struct bio *inmate,
 			struct dm_bio_prison_cell *cell_prealloc,
 			struct dm_bio_prison_cell **cell_result)
 {
 	int r;
-	struct rb_node **new = &prison->cells.rb_node, *parent = NULL;
+	struct rb_node **new = &root->rb_node, *parent = NULL;
 
 	while (*new) {
 		struct dm_bio_prison_cell *cell =
@@ -139,7 +167,7 @@ static int __bio_detain(struct dm_bio_prison *prison,
 	*cell_result = cell_prealloc;
 
 	rb_link_node(&cell_prealloc->node, parent, new);
-	rb_insert_color(&cell_prealloc->node, &prison->cells);
+	rb_insert_color(&cell_prealloc->node, root);
 
 	return 0;
 }
@@ -151,10 +179,11 @@ static int bio_detain(struct dm_bio_prison *prison,
 		      struct dm_bio_prison_cell **cell_result)
 {
 	int r;
+	unsigned l = lock_nr(key, prison->num_locks);
 
-	spin_lock_irq(&prison->lock);
-	r = __bio_detain(prison, key, inmate, cell_prealloc, cell_result);
-	spin_unlock_irq(&prison->lock);
+	spin_lock_irq(&prison->regions[l].lock);
+	r = __bio_detain(&prison->regions[l].cell, key, inmate, cell_prealloc, cell_result);
+	spin_unlock_irq(&prison->regions[l].lock);
 
 	return r;
 }
@@ -181,11 +210,11 @@ EXPORT_SYMBOL_GPL(dm_get_cell);
 /*
  * @inmates must have been initialised prior to this call
  */
-static void __cell_release(struct dm_bio_prison *prison,
+static void __cell_release(struct rb_root *root,
 			   struct dm_bio_prison_cell *cell,
 			   struct bio_list *inmates)
 {
-	rb_erase(&cell->node, &prison->cells);
+	rb_erase(&cell->node, root);
 
 	if (inmates) {
 		if (cell->holder)
@@ -198,20 +227,22 @@ void dm_cell_release(struct dm_bio_prison *prison,
 		     struct dm_bio_prison_cell *cell,
 		     struct bio_list *bios)
 {
-	spin_lock_irq(&prison->lock);
-	__cell_release(prison, cell, bios);
-	spin_unlock_irq(&prison->lock);
+	unsigned l = lock_nr(&cell->key, prison->num_locks);
+
+	spin_lock_irq(&prison->regions[l].lock);
+	__cell_release(&prison->regions[l].cell, cell, bios);
+	spin_unlock_irq(&prison->regions[l].lock);
 }
 EXPORT_SYMBOL_GPL(dm_cell_release);
 
 /*
  * Sometimes we don't want the holder, just the additional bios.
  */
-static void __cell_release_no_holder(struct dm_bio_prison *prison,
+static void __cell_release_no_holder(struct rb_root *root,
 				     struct dm_bio_prison_cell *cell,
 				     struct bio_list *inmates)
 {
-	rb_erase(&cell->node, &prison->cells);
+	rb_erase(&cell->node, root);
 	bio_list_merge(inmates, &cell->bios);
 }
 
@@ -219,11 +250,12 @@ void dm_cell_release_no_holder(struct dm_bio_prison *prison,
 			       struct dm_bio_prison_cell *cell,
 			       struct bio_list *inmates)
 {
+	unsigned l = lock_nr(&cell->key, prison->num_locks);
 	unsigned long flags;
 
-	spin_lock_irqsave(&prison->lock, flags);
-	__cell_release_no_holder(prison, cell, inmates);
-	spin_unlock_irqrestore(&prison->lock, flags);
+	spin_lock_irqsave(&prison->regions[l].lock, flags);
+	__cell_release_no_holder(&prison->regions[l].cell, cell, inmates);
+	spin_unlock_irqrestore(&prison->regions[l].lock, flags);
 }
 EXPORT_SYMBOL_GPL(dm_cell_release_no_holder);
 
@@ -248,18 +280,19 @@ void dm_cell_visit_release(struct dm_bio_prison *prison,
 			   void *context,
 			   struct dm_bio_prison_cell *cell)
 {
-	spin_lock_irq(&prison->lock);
+	unsigned l = lock_nr(&cell->key, prison->num_locks);
+	spin_lock_irq(&prison->regions[l].lock);
 	visit_fn(context, cell);
-	rb_erase(&cell->node, &prison->cells);
-	spin_unlock_irq(&prison->lock);
+	rb_erase(&cell->node, &prison->regions[l].cell);
+	spin_unlock_irq(&prison->regions[l].lock);
 }
 EXPORT_SYMBOL_GPL(dm_cell_visit_release);
 
-static int __promote_or_release(struct dm_bio_prison *prison,
+static int __promote_or_release(struct rb_root *root,
 				struct dm_bio_prison_cell *cell)
 {
 	if (bio_list_empty(&cell->bios)) {
-		rb_erase(&cell->node, &prison->cells);
+		rb_erase(&cell->node, root);
 		return 1;
 	}
 
@@ -271,10 +304,11 @@ int dm_cell_promote_or_release(struct dm_bio_prison *prison,
 			       struct dm_bio_prison_cell *cell)
 {
 	int r;
+	unsigned l = lock_nr(&cell->key, prison->num_locks);
 
-	spin_lock_irq(&prison->lock);
-	r = __promote_or_release(prison, cell);
-	spin_unlock_irq(&prison->lock);
+	spin_lock_irq(&prison->regions[l].lock);
+	r = __promote_or_release(&prison->regions[l].cell, cell);
+	spin_unlock_irq(&prison->regions[l].lock);
 
 	return r;
 }

drivers/md/dm-bio-prison-v1.h

@@ -34,6 +34,16 @@ struct dm_cell_key {
 	dm_block_t block_begin, block_end;
 };
 
+/*
+ * The range of a key (block_end - block_begin) must not
+ * exceed BIO_PRISON_MAX_RANGE.  Also the range must not
+ * cross a similarly sized boundary.
+ *
+ * Must be a power of 2.
+ */
+#define BIO_PRISON_MAX_RANGE 1024
+#define BIO_PRISON_MAX_RANGE_SHIFT 10
+
 /*
  * Treat this as opaque, only in header so callers can manage allocation
  * themselves.
@@ -73,6 +83,11 @@ int dm_get_cell(struct dm_bio_prison *prison,
 		struct dm_bio_prison_cell *cell_prealloc,
 		struct dm_bio_prison_cell **cell_result);
 
+/*
+ * Returns false if key is beyond BIO_PRISON_MAX_RANGE or spans a boundary.
+ */
+bool dm_cell_key_has_valid_range(struct dm_cell_key *key);
+
 /*
  * An atomic op that combines retrieving or creating a cell, and adding a
  * bio to it.

drivers/md/dm-cache-target.c

@@ -3459,7 +3459,6 @@ static int __init dm_cache_init(void)
 
 	r = dm_register_target(&cache_target);
 	if (r) {
-		DMERR("cache target registration failed: %d", r);
 		kmem_cache_destroy(migration_cache);
 		return r;
 	}

drivers/md/dm-clone-target.c

@@ -2204,7 +2204,7 @@ static int __init dm_clone_init(void)
 
 	r = dm_register_target(&clone_target);
 	if (r < 0) {
-		DMERR("Failed to register clone target");
+		kmem_cache_destroy(_hydration_cache);
 		return r;
 	}
 

drivers/md/dm-crypt.c

@@ -3659,25 +3659,7 @@ static struct target_type crypt_target = {
 	.iterate_devices = crypt_iterate_devices,
 	.io_hints = crypt_io_hints,
 };
-
-static int __init dm_crypt_init(void)
-{
-	int r;
-
-	r = dm_register_target(&crypt_target);
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
-}
-
-static void __exit dm_crypt_exit(void)
-{
-	dm_unregister_target(&crypt_target);
-}
-
-module_init(dm_crypt_init);
-module_exit(dm_crypt_exit);
+module_dm(crypt);
 
 MODULE_AUTHOR("Jana Saout <jana@saout.de>");
 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");

drivers/md/dm-delay.c

@@ -367,31 +367,7 @@ static struct target_type delay_target = {
 	.status	     = delay_status,
 	.iterate_devices = delay_iterate_devices,
 };
-
-static int __init dm_delay_init(void)
-{
-	int r;
-
-	r = dm_register_target(&delay_target);
-	if (r < 0) {
-		DMERR("register failed %d", r);
-		goto bad_register;
-	}
-
-	return 0;
-
-bad_register:
-	return r;
-}
-
-static void __exit dm_delay_exit(void)
-{
-	dm_unregister_target(&delay_target);
-}
-
-/* Module hooks */
-module_init(dm_delay_init);
-module_exit(dm_delay_exit);
+module_dm(delay);
 
 MODULE_DESCRIPTION(DM_NAME " delay target");
 MODULE_AUTHOR("Heinz Mauelshagen <mauelshagen@redhat.com>");

drivers/md/dm-dust.c

@@ -570,24 +570,7 @@ static struct target_type dust_target = {
 	.status = dust_status,
 	.prepare_ioctl = dust_prepare_ioctl,
 };
-
-static int __init dm_dust_init(void)
-{
-	int r = dm_register_target(&dust_target);
-
-	if (r < 0)
-		DMERR("dm_register_target failed %d", r);
-
-	return r;
-}
-
-static void __exit dm_dust_exit(void)
-{
-	dm_unregister_target(&dust_target);
-}
-
-module_init(dm_dust_init);
-module_exit(dm_dust_exit);
+module_dm(dust);
 
 MODULE_DESCRIPTION(DM_NAME " dust test target");
 MODULE_AUTHOR("Bryan Gurney <dm-devel@redhat.com>");

drivers/md/dm-ebs-target.c

@@ -452,24 +452,7 @@ static struct target_type ebs_target = {
 	.prepare_ioctl	 = ebs_prepare_ioctl,
 	.iterate_devices = ebs_iterate_devices,
 };
-
-static int __init dm_ebs_init(void)
-{
-	int r = dm_register_target(&ebs_target);
-
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
-}
-
-static void dm_ebs_exit(void)
-{
-	dm_unregister_target(&ebs_target);
-}
-
-module_init(dm_ebs_init);
-module_exit(dm_ebs_exit);
+module_dm(ebs);
 
 MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
 MODULE_DESCRIPTION(DM_NAME " emulated block size target");

drivers/md/dm-era-target.c

@@ -1753,27 +1753,7 @@ static struct target_type era_target = {
 	.iterate_devices = era_iterate_devices,
 	.io_hints = era_io_hints
 };
-
-static int __init dm_era_init(void)
-{
-	int r;
-
-	r = dm_register_target(&era_target);
-	if (r) {
-		DMERR("era target registration failed: %d", r);
-		return r;
-	}
-
-	return 0;
-}
-
-static void __exit dm_era_exit(void)
-{
-	dm_unregister_target(&era_target);
-}
-
-module_init(dm_era_init);
-module_exit(dm_era_exit);
+module_dm(era);
 
 MODULE_DESCRIPTION(DM_NAME " era target");
 MODULE_AUTHOR("Joe Thornber <ejt@redhat.com>");

drivers/md/dm-flakey.c

@@ -37,6 +37,7 @@ struct flakey_c {
 };
 
 enum feature_flag_bits {
+	ERROR_READS,
 	DROP_WRITES,
 	ERROR_WRITES
 };
@@ -53,7 +54,7 @@ static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
 	const char *arg_name;
 
 	static const struct dm_arg _args[] = {
-		{0, 6, "Invalid number of feature args"},
+		{0, 7, "Invalid number of feature args"},
 		{1, UINT_MAX, "Invalid corrupt bio byte"},
 		{0, 255, "Invalid corrupt value to write into bio byte (0-255)"},
 		{0, UINT_MAX, "Invalid corrupt bio flags mask"},
@@ -76,6 +77,17 @@ static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
 			return -EINVAL;
 		}
 
+		/*
+		 * error_reads
+		 */
+		if (!strcasecmp(arg_name, "error_reads")) {
+			if (test_and_set_bit(ERROR_READS, &fc->flags)) {
+				ti->error = "Feature error_reads duplicated";
+				return -EINVAL;
+			}
+			continue;
+		}
+
 		/*
 		 * drop_writes
 		 */
@@ -125,9 +137,9 @@ static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
 			 * Direction r or w?
 			 */
 			arg_name = dm_shift_arg(as);
-			if (!strcasecmp(arg_name, "w"))
+			if (arg_name && !strcasecmp(arg_name, "w"))
 				fc->corrupt_bio_rw = WRITE;
-			else if (!strcasecmp(arg_name, "r"))
+			else if (arg_name && !strcasecmp(arg_name, "r"))
 				fc->corrupt_bio_rw = READ;
 			else {
 				ti->error = "Invalid corrupt bio direction (r or w)";
@@ -171,6 +183,12 @@ static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
 		return -EINVAL;
 	}
 
+	if (!fc->corrupt_bio_byte && !test_bit(ERROR_READS, &fc->flags) &&
+	    !test_bit(DROP_WRITES, &fc->flags) && !test_bit(ERROR_WRITES, &fc->flags)) {
+		set_bit(ERROR_WRITES, &fc->flags);
+		set_bit(ERROR_READS, &fc->flags);
+	}
+
 	return 0;
 }
 
@@ -346,8 +364,7 @@ static int flakey_map(struct dm_target *ti, struct bio *bio)
 		 * Otherwise, flakey_end_io() will decide if the reads should be modified.
 		 */
 		if (bio_data_dir(bio) == READ) {
-			if (!fc->corrupt_bio_byte && !test_bit(DROP_WRITES, &fc->flags) &&
-			    !test_bit(ERROR_WRITES, &fc->flags))
+			if (test_bit(ERROR_READS, &fc->flags))
 				return DM_MAPIO_KILL;
 			goto map_bio;
 		}
@@ -373,11 +390,6 @@ static int flakey_map(struct dm_target *ti, struct bio *bio)
 			}
 			goto map_bio;
 		}
-
-		/*
-		 * By default, error all I/O.
-		 */
-		return DM_MAPIO_KILL;
 	}
 
 map_bio:
@@ -404,8 +416,8 @@ static int flakey_end_io(struct dm_target *ti, struct bio *bio,
 				 */
 				corrupt_bio_data(bio, fc);
 			}
-		} else if (!test_bit(DROP_WRITES, &fc->flags) &&
-			   !test_bit(ERROR_WRITES, &fc->flags)) {
+		}
+		if (test_bit(ERROR_READS, &fc->flags)) {
 			/*
 			 * Error read during the down_interval if drop_writes
 			 * and error_writes were not configured.
@@ -422,7 +434,7 @@ static void flakey_status(struct dm_target *ti, status_type_t type,
 {
 	unsigned int sz = 0;
 	struct flakey_c *fc = ti->private;
-	unsigned int drop_writes, error_writes;
+	unsigned int error_reads, drop_writes, error_writes;
 
 	switch (type) {
 	case STATUSTYPE_INFO:
@@ -430,21 +442,24 @@ static void flakey_status(struct dm_target *ti, status_type_t type,
 		break;
 
 	case STATUSTYPE_TABLE:
-		DMEMIT("%s %llu %u %u ", fc->dev->name,
+		DMEMIT("%s %llu %u %u", fc->dev->name,
 		       (unsigned long long)fc->start, fc->up_interval,
 		       fc->down_interval);
 
+		error_reads = test_bit(ERROR_READS, &fc->flags);
 		drop_writes = test_bit(DROP_WRITES, &fc->flags);
 		error_writes = test_bit(ERROR_WRITES, &fc->flags);
-		DMEMIT("%u ", drop_writes + error_writes + (fc->corrupt_bio_byte > 0) * 5);
+		DMEMIT(" %u", error_reads + drop_writes + error_writes + (fc->corrupt_bio_byte > 0) * 5);
 
+		if (error_reads)
+			DMEMIT(" error_reads");
 		if (drop_writes)
-			DMEMIT("drop_writes ");
+			DMEMIT(" drop_writes");
 		else if (error_writes)
-			DMEMIT("error_writes ");
+			DMEMIT(" error_writes");
 
 		if (fc->corrupt_bio_byte)
-			DMEMIT("corrupt_bio_byte %u %c %u %u ",
+			DMEMIT(" corrupt_bio_byte %u %c %u %u",
 			       fc->corrupt_bio_byte,
 			       (fc->corrupt_bio_rw == WRITE) ? 'w' : 'r',
 			       fc->corrupt_bio_value, fc->corrupt_bio_flags);
@@ -506,25 +521,7 @@ static struct target_type flakey_target = {
 	.prepare_ioctl = flakey_prepare_ioctl,
 	.iterate_devices = flakey_iterate_devices,
 };
-
-static int __init dm_flakey_init(void)
-{
-	int r = dm_register_target(&flakey_target);
-
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
-}
-
-static void __exit dm_flakey_exit(void)
-{
-	dm_unregister_target(&flakey_target);
-}
-
-/* Module hooks */
-module_init(dm_flakey_init);
-module_exit(dm_flakey_exit);
+module_dm(flakey);
 
 MODULE_DESCRIPTION(DM_NAME " flakey target");
 MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");

drivers/md/dm-integrity.c

@@ -3118,7 +3118,7 @@ static int dm_integrity_reboot(struct notifier_block *n, unsigned long code, voi
 
 static void dm_integrity_postsuspend(struct dm_target *ti)
 {
-	struct dm_integrity_c *ic = (struct dm_integrity_c *)ti->private;
+	struct dm_integrity_c *ic = ti->private;
 	int r;
 
 	WARN_ON(unregister_reboot_notifier(&ic->reboot_notifier));
@@ -3167,7 +3167,7 @@ static void dm_integrity_postsuspend(struct dm_target *ti)
 
 static void dm_integrity_resume(struct dm_target *ti)
 {
-	struct dm_integrity_c *ic = (struct dm_integrity_c *)ti->private;
+	struct dm_integrity_c *ic = ti->private;
 	__u64 old_provided_data_sectors = le64_to_cpu(ic->sb->provided_data_sectors);
 	int r;
 
@@ -3290,7 +3290,7 @@ static void dm_integrity_resume(struct dm_target *ti)
 static void dm_integrity_status(struct dm_target *ti, status_type_t type,
 				unsigned int status_flags, char *result, unsigned int maxlen)
 {
-	struct dm_integrity_c *ic = (struct dm_integrity_c *)ti->private;
+	struct dm_integrity_c *ic = ti->private;
 	unsigned int arg_count;
 	size_t sz = 0;
 
@@ -4703,11 +4703,12 @@ static int __init dm_integrity_init(void)
 	}
 
 	r = dm_register_target(&integrity_target);
+	if (r < 0) {
+		kmem_cache_destroy(journal_io_cache);
+		return r;
+	}
 
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
+	return 0;
 }
 
 static void __exit dm_integrity_exit(void)

drivers/md/dm-io.c

@@ -187,7 +187,7 @@ static void list_get_page(struct dpages *dp,
 		  struct page **p, unsigned long *len, unsigned int *offset)
 {
 	unsigned int o = dp->context_u;
-	struct page_list *pl = (struct page_list *) dp->context_ptr;
+	struct page_list *pl = dp->context_ptr;
 
 	*p = pl->page;
 	*len = PAGE_SIZE - o;
@@ -196,7 +196,7 @@ static void list_get_page(struct dpages *dp,
 
 static void list_next_page(struct dpages *dp)
 {
-	struct page_list *pl = (struct page_list *) dp->context_ptr;
+	struct page_list *pl = dp->context_ptr;
 
 	dp->context_ptr = pl->next;
 	dp->context_u = 0;

drivers/md/dm-ioctl.c

@@ -1168,10 +1168,13 @@ static int do_resume(struct dm_ioctl *param)
 	/* Do we need to load a new map ? */
 	if (new_map) {
 		sector_t old_size, new_size;
+		int srcu_idx;
 
 		/* Suspend if it isn't already suspended */
-		if (param->flags & DM_SKIP_LOCKFS_FLAG)
+		old_map = dm_get_live_table(md, &srcu_idx);
+		if ((param->flags & DM_SKIP_LOCKFS_FLAG) || !old_map)
 			suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
+		dm_put_live_table(md, srcu_idx);
 		if (param->flags & DM_NOFLUSH_FLAG)
 			suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
 		if (!dm_suspended_md(md))
@@ -1556,11 +1559,12 @@ static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_s
 		has_new_map = true;
 	}
 
-	param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
-
-	__dev_status(hc->md, param);
 	md = hc->md;
 	up_write(&_hash_lock);
+
+	param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
+	__dev_status(md, param);
+
 	if (old_map) {
 		dm_sync_table(md);
 		dm_table_destroy(old_map);

drivers/md/dm-kcopyd.c

@@ -519,7 +519,7 @@ static int run_complete_job(struct kcopyd_job *job)
 
 static void complete_io(unsigned long error, void *context)
 {
-	struct kcopyd_job *job = (struct kcopyd_job *) context;
+	struct kcopyd_job *job = context;
 	struct dm_kcopyd_client *kc = job->kc;
 
 	io_job_finish(kc->throttle);
@@ -696,7 +696,7 @@ static void segment_complete(int read_err, unsigned long write_err,
 	/* FIXME: tidy this function */
 	sector_t progress = 0;
 	sector_t count = 0;
-	struct kcopyd_job *sub_job = (struct kcopyd_job *) context;
+	struct kcopyd_job *sub_job = context;
 	struct kcopyd_job *job = sub_job->master_job;
 	struct dm_kcopyd_client *kc = job->kc;
 

drivers/md/dm-linear.c

@@ -72,7 +72,7 @@ static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
 static void linear_dtr(struct dm_target *ti)
 {
-	struct linear_c *lc = (struct linear_c *) ti->private;
+	struct linear_c *lc = ti->private;
 
 	dm_put_device(ti, lc->dev);
 	kfree(lc);
@@ -98,7 +98,7 @@ static int linear_map(struct dm_target *ti, struct bio *bio)
 static void linear_status(struct dm_target *ti, status_type_t type,
 			  unsigned int status_flags, char *result, unsigned int maxlen)
 {
-	struct linear_c *lc = (struct linear_c *) ti->private;
+	struct linear_c *lc = ti->private;
 	size_t sz = 0;
 
 	switch (type) {
@@ -120,7 +120,7 @@ static void linear_status(struct dm_target *ti, status_type_t type,
 
 static int linear_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
 {
-	struct linear_c *lc = (struct linear_c *) ti->private;
+	struct linear_c *lc = ti->private;
 	struct dm_dev *dev = lc->dev;
 
 	*bdev = dev->bdev;

drivers/md/dm-log-writes.c

@@ -429,7 +429,7 @@ static inline sector_t logdev_last_sector(struct log_writes_c *lc)
 
 static int log_writes_kthread(void *arg)
 {
-	struct log_writes_c *lc = (struct log_writes_c *)arg;
+	struct log_writes_c *lc = arg;
 	sector_t sector = 0;
 
 	while (!kthread_should_stop()) {
@@ -937,24 +937,7 @@ static struct target_type log_writes_target = {
 	.dax_zero_page_range = log_writes_dax_zero_page_range,
 	.dax_recovery_write = log_writes_dax_recovery_write,
 };
-
-static int __init dm_log_writes_init(void)
-{
-	int r = dm_register_target(&log_writes_target);
-
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
-}
-
-static void __exit dm_log_writes_exit(void)
-{
-	dm_unregister_target(&log_writes_target);
-}
-
-module_init(dm_log_writes_init);
-module_exit(dm_log_writes_exit);
+module_dm(log_writes);
 
 MODULE_DESCRIPTION(DM_NAME " log writes target");
 MODULE_AUTHOR("Josef Bacik <jbacik@fb.com>");

drivers/md/dm-log.c

@@ -530,7 +530,7 @@ static void destroy_log_context(struct log_c *lc)
 
 static void core_dtr(struct dm_dirty_log *log)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	vfree(lc->clean_bits);
 	destroy_log_context(lc);
@@ -569,7 +569,7 @@ static int disk_ctr(struct dm_dirty_log *log, struct dm_target *ti,
 
 static void disk_dtr(struct dm_dirty_log *log)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	dm_put_device(lc->ti, lc->log_dev);
 	vfree(lc->disk_header);
@@ -590,7 +590,7 @@ static int disk_resume(struct dm_dirty_log *log)
 {
 	int r;
 	unsigned int i;
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 	size_t size = lc->bitset_uint32_count * sizeof(uint32_t);
 
 	/* read the disk header */
@@ -652,14 +652,14 @@ static int disk_resume(struct dm_dirty_log *log)
 
 static uint32_t core_get_region_size(struct dm_dirty_log *log)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	return lc->region_size;
 }
 
 static int core_resume(struct dm_dirty_log *log)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	lc->sync_search = 0;
 	return 0;
@@ -667,14 +667,14 @@ static int core_resume(struct dm_dirty_log *log)
 
 static int core_is_clean(struct dm_dirty_log *log, region_t region)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	return log_test_bit(lc->clean_bits, region);
 }
 
 static int core_in_sync(struct dm_dirty_log *log, region_t region, int block)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	return log_test_bit(lc->sync_bits, region);
 }
@@ -727,14 +727,14 @@ static int disk_flush(struct dm_dirty_log *log)
 
 static void core_mark_region(struct dm_dirty_log *log, region_t region)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	log_clear_bit(lc, lc->clean_bits, region);
 }
 
 static void core_clear_region(struct dm_dirty_log *log, region_t region)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	if (likely(!lc->flush_failed))
 		log_set_bit(lc, lc->clean_bits, region);
@@ -742,7 +742,7 @@ static void core_clear_region(struct dm_dirty_log *log, region_t region)
 
 static int core_get_resync_work(struct dm_dirty_log *log, region_t *region)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	if (lc->sync_search >= lc->region_count)
 		return 0;
@@ -765,7 +765,7 @@ static int core_get_resync_work(struct dm_dirty_log *log, region_t *region)
 static void core_set_region_sync(struct dm_dirty_log *log, region_t region,
 				 int in_sync)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	log_clear_bit(lc, lc->recovering_bits, region);
 	if (in_sync) {
@@ -779,7 +779,7 @@ static void core_set_region_sync(struct dm_dirty_log *log, region_t region,
 
 static region_t core_get_sync_count(struct dm_dirty_log *log)
 {
-	struct log_c *lc = (struct log_c *) log->context;
+	struct log_c *lc = log->context;
 
 	return lc->sync_count;
 }

drivers/md/dm-mpath.c

@@ -2235,11 +2235,8 @@ static int __init dm_multipath_init(void)
 	}
 
 	r = dm_register_target(&multipath_target);
-	if (r < 0) {
-		DMERR("request-based register failed %d", r);
-		r = -EINVAL;
+	if (r < 0)
 		goto bad_register_target;
-	}
 
 	return 0;