Merge tag 'dm-4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Most attention this cycle went to optimizing blk-mq request-based DM
   (dm-mq) that is used exclussively by DM multipath:

     - A stable fix for dm-mq that eliminates excessive context
       switching offers the biggest performance improvement (for both
       IOPs and throughput).

     - But more work is needed, during the next cycle, to reduce
       spinlock contention in DM multipath on large NUMA systems.

 - A stable fix for a NULL pointer seen when DM stats is enabled on a DM
   multipath device that must requeue an IO due to path failure.

 - A stable fix for DM snapshot to disallow the COW and origin devices
   from being identical.  This amounts to graceful failure in the face
   of userspace error because these devices shouldn't ever be identical.

 - Stable fixes for DM cache and DM thin provisioning to address crashes
   seen if/when their respective metadata device experiences failures
   that cause the transition to 'fail_io' mode.

 - The DM cache 'mq' policy is now an alias for the 'smq' policy.  The
   'smq' policy proved to be consistently better than 'mq'.  As such
   'mq', with all its complex user-facing tunables, has been eliminated.

 - Improve DM thin provisioning to consistently return -ENOSPC once the
   thin-pool's data volume is out of space.

 - Improve DM core to properly handle error propagation if
   bio_integrity_clone() fails in clone_bio().

 - Other small cleanups and improvements to DM core.

* tag 'dm-4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (41 commits)
  dm: fix rq_end_stats() NULL pointer in dm_requeue_original_request()
  dm thin: consistently return -ENOSPC if pool has run out of data space
  dm cache: bump the target version
  dm cache: make sure every metadata function checks fail_io
  dm: add missing newline between DM_DEBUG_BLOCK_STACK_TRACING and DM_BUFIO
  dm cache policy smq: clarify that mq registration failure was for 'mq'
  dm: return error if bio_integrity_clone() fails in clone_bio()
  dm thin metadata: don't issue prefetches if a transaction abort has failed
  dm snapshot: disallow the COW and origin devices from being identical
  dm cache: make the 'mq' policy an alias for 'smq'
  dm: drop unnecessary assignment of md->queue
  dm: reorder 'struct mapped_device' members to fix alignment and holes
  dm: remove dummy definition of 'struct dm_table'
  dm: add 'dm_numa_node' module parameter
  dm thin metadata: remove needless newline from subtree_dec() DMERR message
  dm mpath: cleanup reinstate_path() et al based on code review
  dm mpath: remove __pgpath_busy forward declaration, rename to pgpath_busy
  dm mpath: switch from 'unsigned' to 'bool' for flags where appropriate
  dm round robin: use percpu 'repeat_count' and 'current_path'
  dm path selector: remove 'repeat_count' return from .select_path hook
  ...

Documentation/device-mapper/cache-policies.txt

@@ -28,51 +28,16 @@ Overview of supplied cache replacement policies
 multiqueue (mq)
 ---------------
 
-This policy has been deprecated in favor of the smq policy (see below).
+This policy is now an alias for smq (see below).
 
-The multiqueue policy has three sets of 16 queues: one set for entries
-waiting for the cache and another two for those in the cache (a set for
-clean entries and a set for dirty entries).
+The following tunables are accepted, but have no effect:
 
-Cache entries in the queues are aged based on logical time. Entry into
-the cache is based on variable thresholds and queue selection is based
-on hit count on entry. The policy aims to take different cache miss
-costs into account and to adjust to varying load patterns automatically.
-
-Message and constructor argument pairs are:
 	'sequential_threshold <#nr_sequential_ios>'
 	'random_threshold <#nr_random_ios>'
 	'read_promote_adjustment <value>'
 	'write_promote_adjustment <value>'
 	'discard_promote_adjustment <value>'
 
-The sequential threshold indicates the number of contiguous I/Os
-required before a stream is treated as sequential.  Once a stream is
-considered sequential it will bypass the cache.  The random threshold
-is the number of intervening non-contiguous I/Os that must be seen
-before the stream is treated as random again.
-
-The sequential and random thresholds default to 512 and 4 respectively.
-
-Large, sequential I/Os are probably better left on the origin device
-since spindles tend to have good sequential I/O bandwidth.  The
-io_tracker counts contiguous I/Os to try to spot when the I/O is in one
-of these sequential modes.  But there are use-cases for wanting to
-promote sequential blocks to the cache (e.g. fast application startup).
-If sequential threshold is set to 0 the sequential I/O detection is
-disabled and sequential I/O will no longer implicitly bypass the cache.
-Setting the random threshold to 0 does _not_ disable the random I/O
-stream detection.
-
-Internally the mq policy determines a promotion threshold.  If the hit
-count of a block not in the cache goes above this threshold it gets
-promoted to the cache.  The read, write and discard promote adjustment
-tunables allow you to tweak the promotion threshold by adding a small
-value based on the io type.  They default to 4, 8 and 1 respectively.
-If you're trying to quickly warm a new cache device you may wish to
-reduce these to encourage promotion.  Remember to switch them back to
-their defaults after the cache fills though.
-
 Stochastic multiqueue (smq)
 ---------------------------
 

block/blk-core.c

@@ -2198,7 +2198,7 @@ int blk_insert_cloned_request(struct request_queue *q, struct request *rq)
 	if (q->mq_ops) {
 		if (blk_queue_io_stat(q))
 			blk_account_io_start(rq, true);
-		blk_mq_insert_request(rq, false, true, true);
+		blk_mq_insert_request(rq, false, true, false);
 		return 0;
 	}
 

drivers/md/Kconfig

@@ -249,6 +249,7 @@ config DM_DEBUG_BLOCK_STACK_TRACING
 	 block manager locking used by thin provisioning and caching.
 
 	 If unsure, say N.
+
 config DM_BIO_PRISON
        tristate
        depends on BLK_DEV_DM
@@ -304,16 +305,6 @@ config DM_CACHE
          algorithms used to select which blocks are promoted, demoted,
          cleaned etc.  It supports writeback and writethrough modes.
 
-config DM_CACHE_MQ
-       tristate "MQ Cache Policy (EXPERIMENTAL)"
-       depends on DM_CACHE
-       default y
-       ---help---
-         A cache policy that uses a multiqueue ordered by recent hit
-         count to select which blocks should be promoted and demoted.
-         This is meant to be a general purpose policy.  It prioritises
-         reads over writes.
-
 config DM_CACHE_SMQ
        tristate "Stochastic MQ Cache Policy (EXPERIMENTAL)"
        depends on DM_CACHE

drivers/md/Makefile

@@ -12,7 +12,6 @@ dm-log-userspace-y \
 		+= dm-log-userspace-base.o dm-log-userspace-transfer.o
 dm-thin-pool-y	+= dm-thin.o dm-thin-metadata.o
 dm-cache-y	+= dm-cache-target.o dm-cache-metadata.o dm-cache-policy.o
-dm-cache-mq-y   += dm-cache-policy-mq.o
 dm-cache-smq-y   += dm-cache-policy-smq.o
 dm-cache-cleaner-y += dm-cache-policy-cleaner.o
 dm-era-y	+= dm-era-target.o
@@ -55,7 +54,6 @@ obj-$(CONFIG_DM_RAID)	+= dm-raid.o
 obj-$(CONFIG_DM_THIN_PROVISIONING)	+= dm-thin-pool.o
 obj-$(CONFIG_DM_VERITY)		+= dm-verity.o
 obj-$(CONFIG_DM_CACHE)		+= dm-cache.o
-obj-$(CONFIG_DM_CACHE_MQ)	+= dm-cache-mq.o
 obj-$(CONFIG_DM_CACHE_SMQ)	+= dm-cache-smq.o
 obj-$(CONFIG_DM_CACHE_CLEANER)	+= dm-cache-cleaner.o
 obj-$(CONFIG_DM_ERA)		+= dm-era.o

drivers/md/dm-cache-metadata.c

@@ -867,19 +867,40 @@ static int blocks_are_unmapped_or_clean(struct dm_cache_metadata *cmd,
 	return 0;
 }
 
-#define WRITE_LOCK(cmd) \
-	if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) \
+#define WRITE_LOCK(cmd)	\
+	down_write(&cmd->root_lock); \
+	if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \
+		up_write(&cmd->root_lock); \
 		return -EINVAL; \
-	down_write(&cmd->root_lock)
+	}
 
 #define WRITE_LOCK_VOID(cmd) \
-	if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) \
+	down_write(&cmd->root_lock); \
+	if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \
+		up_write(&cmd->root_lock); \
 		return; \
-	down_write(&cmd->root_lock)
+	}
 
 #define WRITE_UNLOCK(cmd) \
 	up_write(&cmd->root_lock)
 
+#define READ_LOCK(cmd) \
+	down_read(&cmd->root_lock); \
+	if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \
+		up_read(&cmd->root_lock); \
+		return -EINVAL; \
+	}
+
+#define READ_LOCK_VOID(cmd)	\
+	down_read(&cmd->root_lock); \
+	if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \
+		up_read(&cmd->root_lock); \
+		return; \
+	}
+
+#define READ_UNLOCK(cmd) \
+	up_read(&cmd->root_lock)
+
 int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size)
 {
 	int r;
@@ -1015,22 +1036,20 @@ int dm_cache_load_discards(struct dm_cache_metadata *cmd,
 {
 	int r;
 
-	down_read(&cmd->root_lock);
+	READ_LOCK(cmd);
 	r = __load_discards(cmd, fn, context);
-	up_read(&cmd->root_lock);
+	READ_UNLOCK(cmd);
 
 	return r;
 }
 
-dm_cblock_t dm_cache_size(struct dm_cache_metadata *cmd)
+int dm_cache_size(struct dm_cache_metadata *cmd, dm_cblock_t *result)
 {
-	dm_cblock_t r;
+	READ_LOCK(cmd);
+	*result = cmd->cache_blocks;
+	READ_UNLOCK(cmd);
 
-	down_read(&cmd->root_lock);
-	r = cmd->cache_blocks;
-	up_read(&cmd->root_lock);
-
-	return r;
+	return 0;
 }
 
 static int __remove(struct dm_cache_metadata *cmd, dm_cblock_t cblock)
@@ -1188,9 +1207,9 @@ int dm_cache_load_mappings(struct dm_cache_metadata *cmd,
 {
 	int r;
 
-	down_read(&cmd->root_lock);
+	READ_LOCK(cmd);
 	r = __load_mappings(cmd, policy, fn, context);
-	up_read(&cmd->root_lock);
+	READ_UNLOCK(cmd);
 
 	return r;
 }
@@ -1215,18 +1234,18 @@ static int __dump_mappings(struct dm_cache_metadata *cmd)
 
 void dm_cache_dump(struct dm_cache_metadata *cmd)
 {
-	down_read(&cmd->root_lock);
+	READ_LOCK_VOID(cmd);
 	__dump_mappings(cmd);
-	up_read(&cmd->root_lock);
+	READ_UNLOCK(cmd);
 }
 
 int dm_cache_changed_this_transaction(struct dm_cache_metadata *cmd)
 {
 	int r;
 
-	down_read(&cmd->root_lock);
+	READ_LOCK(cmd);
 	r = cmd->changed;
-	up_read(&cmd->root_lock);
+	READ_UNLOCK(cmd);
 
 	return r;
 }
@@ -1276,9 +1295,9 @@ int dm_cache_set_dirty(struct dm_cache_metadata *cmd,
 void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd,
 				 struct dm_cache_statistics *stats)
 {
-	down_read(&cmd->root_lock);
+	READ_LOCK_VOID(cmd);
 	*stats = cmd->stats;
-	up_read(&cmd->root_lock);
+	READ_UNLOCK(cmd);
 }
 
 void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd,
@@ -1312,9 +1331,9 @@ int dm_cache_get_free_metadata_block_count(struct dm_cache_metadata *cmd,
 {
 	int r = -EINVAL;
 
-	down_read(&cmd->root_lock);
+	READ_LOCK(cmd);
 	r = dm_sm_get_nr_free(cmd->metadata_sm, result);
-	up_read(&cmd->root_lock);
+	READ_UNLOCK(cmd);
 
 	return r;
 }
@@ -1324,9 +1343,9 @@ int dm_cache_get_metadata_dev_size(struct dm_cache_metadata *cmd,
 {
 	int r = -EINVAL;
 
-	down_read(&cmd->root_lock);
+	READ_LOCK(cmd);
 	r = dm_sm_get_nr_blocks(cmd->metadata_sm, result);
-	up_read(&cmd->root_lock);
+	READ_UNLOCK(cmd);
 
 	return r;
 }
@@ -1417,7 +1436,13 @@ int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *
 
 int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result)
 {
-	return blocks_are_unmapped_or_clean(cmd, 0, cmd->cache_blocks, result);
+	int r;
+
+	READ_LOCK(cmd);
+	r = blocks_are_unmapped_or_clean(cmd, 0, cmd->cache_blocks, result);
+	READ_UNLOCK(cmd);
+
+	return r;
 }
 
 void dm_cache_metadata_set_read_only(struct dm_cache_metadata *cmd)
@@ -1440,10 +1465,7 @@ int dm_cache_metadata_set_needs_check(struct dm_cache_metadata *cmd)
 	struct dm_block *sblock;
 	struct cache_disk_superblock *disk_super;
 
-	/*
-	 * We ignore fail_io for this function.
-	 */
-	down_write(&cmd->root_lock);
+	WRITE_LOCK(cmd);
 	set_bit(NEEDS_CHECK, &cmd->flags);
 
 	r = superblock_lock(cmd, &sblock);
@@ -1458,19 +1480,17 @@ int dm_cache_metadata_set_needs_check(struct dm_cache_metadata *cmd)
 	dm_bm_unlock(sblock);
 
 out:
-	up_write(&cmd->root_lock);
+	WRITE_UNLOCK(cmd);
 	return r;
 }
 
-bool dm_cache_metadata_needs_check(struct dm_cache_metadata *cmd)
+int dm_cache_metadata_needs_check(struct dm_cache_metadata *cmd, bool *result)
 {
-	bool needs_check;
+	READ_LOCK(cmd);
+	*result = !!test_bit(NEEDS_CHECK, &cmd->flags);
+	READ_UNLOCK(cmd);
 
-	down_read(&cmd->root_lock);
-	needs_check = !!test_bit(NEEDS_CHECK, &cmd->flags);
-	up_read(&cmd->root_lock);
-
-	return needs_check;
+	return 0;
 }
 
 int dm_cache_metadata_abort(struct dm_cache_metadata *cmd)

drivers/md/dm-cache-metadata.h

@@ -66,7 +66,7 @@ void dm_cache_metadata_close(struct dm_cache_metadata *cmd);
  * origin blocks to map to.
  */
 int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size);
-dm_cblock_t dm_cache_size(struct dm_cache_metadata *cmd);
+int dm_cache_size(struct dm_cache_metadata *cmd, dm_cblock_t *result);
 
 int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd,
 				   sector_t discard_block_size,
@@ -137,7 +137,7 @@ int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *
  */
 int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result);
 
-bool dm_cache_metadata_needs_check(struct dm_cache_metadata *cmd);
+int dm_cache_metadata_needs_check(struct dm_cache_metadata *cmd, bool *result);
 int dm_cache_metadata_set_needs_check(struct dm_cache_metadata *cmd);
 void dm_cache_metadata_set_read_only(struct dm_cache_metadata *cmd);
 void dm_cache_metadata_set_read_write(struct dm_cache_metadata *cmd);

drivers/md/dm-cache-policy-smq.c

@@ -1567,8 +1567,48 @@ static void smq_tick(struct dm_cache_policy *p, bool can_block)
 	spin_unlock_irqrestore(&mq->lock, flags);
 }
 
+/*
+ * smq has no config values, but the old mq policy did.  To avoid breaking
+ * software we continue to accept these configurables for the mq policy,
+ * but they have no effect.
+ */
+static int mq_set_config_value(struct dm_cache_policy *p,
+			       const char *key, const char *value)
+{
+	unsigned long tmp;
+
+	if (kstrtoul(value, 10, &tmp))
+		return -EINVAL;
+
+	if (!strcasecmp(key, "random_threshold") ||
+	    !strcasecmp(key, "sequential_threshold") ||
+	    !strcasecmp(key, "discard_promote_adjustment") ||
+	    !strcasecmp(key, "read_promote_adjustment") ||
+	    !strcasecmp(key, "write_promote_adjustment")) {
+		DMWARN("tunable '%s' no longer has any effect, mq policy is now an alias for smq", key);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int mq_emit_config_values(struct dm_cache_policy *p, char *result,
+				 unsigned maxlen, ssize_t *sz_ptr)
+{
+	ssize_t sz = *sz_ptr;
+
+	DMEMIT("10 random_threshold 0 "
+	       "sequential_threshold 0 "
+	       "discard_promote_adjustment 0 "
+	       "read_promote_adjustment 0 "
+	       "write_promote_adjustment 0 ");
+
+	*sz_ptr = sz;
+	return 0;
+}
+
 /* Init the policy plugin interface function pointers. */
-static void init_policy_functions(struct smq_policy *mq)
+static void init_policy_functions(struct smq_policy *mq, bool mimic_mq)
 {
 	mq->policy.destroy = smq_destroy;
 	mq->policy.map = smq_map;
@@ -1583,6 +1623,11 @@ static void init_policy_functions(struct smq_policy *mq)
 	mq->policy.force_mapping = smq_force_mapping;
 	mq->policy.residency = smq_residency;
 	mq->policy.tick = smq_tick;
+
+	if (mimic_mq) {
+		mq->policy.set_config_value = mq_set_config_value;
+		mq->policy.emit_config_values = mq_emit_config_values;
+	}
 }
 
 static bool too_many_hotspot_blocks(sector_t origin_size,
@@ -1606,9 +1651,10 @@ static void calc_hotspot_params(sector_t origin_size,
 		*hotspot_block_size /= 2u;
 }
 
-static struct dm_cache_policy *smq_create(dm_cblock_t cache_size,
-					  sector_t origin_size,
-					  sector_t cache_block_size)
+static struct dm_cache_policy *__smq_create(dm_cblock_t cache_size,
+					    sector_t origin_size,
+					    sector_t cache_block_size,
+					    bool mimic_mq)
 {
 	unsigned i;
 	unsigned nr_sentinels_per_queue = 2u * NR_CACHE_LEVELS;
@@ -1618,7 +1664,7 @@ static struct dm_cache_policy *smq_create(dm_cblock_t cache_size,
 	if (!mq)
 		return NULL;
 
-	init_policy_functions(mq);
+	init_policy_functions(mq, mimic_mq);
 	mq->cache_size = cache_size;
 	mq->cache_block_size = cache_block_size;
 
@@ -1706,19 +1752,41 @@ bad_pool_init:
 	return NULL;
 }
 
+static struct dm_cache_policy *smq_create(dm_cblock_t cache_size,
+					  sector_t origin_size,
+					  sector_t cache_block_size)
+{
+	return __smq_create(cache_size, origin_size, cache_block_size, false);
+}
+
+static struct dm_cache_policy *mq_create(dm_cblock_t cache_size,
+					 sector_t origin_size,
+					 sector_t cache_block_size)
+{
+	return __smq_create(cache_size, origin_size, cache_block_size, true);
+}
+
 /*----------------------------------------------------------------*/
 
 static struct dm_cache_policy_type smq_policy_type = {
 	.name = "smq",
-	.version = {1, 0, 0},
+	.version = {1, 5, 0},
 	.hint_size = 4,
 	.owner = THIS_MODULE,
 	.create = smq_create
 };
 
+static struct dm_cache_policy_type mq_policy_type = {
+	.name = "mq",
+	.version = {1, 5, 0},
+	.hint_size = 4,
+	.owner = THIS_MODULE,
+	.create = mq_create,
+};
+
 static struct dm_cache_policy_type default_policy_type = {
 	.name = "default",
-	.version = {1, 4, 0},
+	.version = {1, 5, 0},
 	.hint_size = 4,
 	.owner = THIS_MODULE,
 	.create = smq_create,
@@ -1735,9 +1803,17 @@ static int __init smq_init(void)
 		return -ENOMEM;
 	}
 
+	r = dm_cache_policy_register(&mq_policy_type);
+	if (r) {
+		DMERR("register failed (as mq) %d", r);
+		dm_cache_policy_unregister(&smq_policy_type);
+		return -ENOMEM;
+	}
+
 	r = dm_cache_policy_register(&default_policy_type);
 	if (r) {
 		DMERR("register failed (as default) %d", r);
+		dm_cache_policy_unregister(&mq_policy_type);
 		dm_cache_policy_unregister(&smq_policy_type);
 		return -ENOMEM;
 	}
@@ -1748,6 +1824,7 @@ static int __init smq_init(void)
 static void __exit smq_exit(void)
 {
 	dm_cache_policy_unregister(&smq_policy_type);
+	dm_cache_policy_unregister(&mq_policy_type);
 	dm_cache_policy_unregister(&default_policy_type);
 }
 
@@ -1759,3 +1836,4 @@ MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("smq cache policy");
 
 MODULE_ALIAS("dm-cache-default");
+MODULE_ALIAS("dm-cache-mq");

drivers/md/dm-cache-target.c

@@ -984,9 +984,14 @@ static void notify_mode_switch(struct cache *cache, enum cache_metadata_mode mod
 
 static void set_cache_mode(struct cache *cache, enum cache_metadata_mode new_mode)
 {
-	bool needs_check = dm_cache_metadata_needs_check(cache->cmd);
+	bool needs_check;
 	enum cache_metadata_mode old_mode = get_cache_mode(cache);
 
+	if (dm_cache_metadata_needs_check(cache->cmd, &needs_check)) {
+		DMERR("unable to read needs_check flag, setting failure mode");
+		new_mode = CM_FAIL;
+	}
+
 	if (new_mode == CM_WRITE && needs_check) {
 		DMERR("%s: unable to switch cache to write mode until repaired.",
 		      cache_device_name(cache));
@@ -2771,7 +2776,7 @@ static int cache_create(struct cache_args *ca, struct cache **result)
 	ti->split_discard_bios = false;
 
 	cache->features = ca->features;
-	ti->per_bio_data_size = get_per_bio_data_size(cache);
+	ti->per_io_data_size = get_per_bio_data_size(cache);
 
 	cache->callbacks.congested_fn = cache_is_congested;
 	dm_table_add_target_callbacks(ti->table, &cache->callbacks);
@@ -3510,6 +3515,7 @@ static void cache_status(struct dm_target *ti, status_type_t type,
 	char buf[BDEVNAME_SIZE];
 	struct cache *cache = ti->private;
 	dm_cblock_t residency;
+	bool needs_check;
 
 	switch (type) {
 	case STATUSTYPE_INFO:
@@ -3583,7 +3589,9 @@ static void cache_status(struct dm_target *ti, status_type_t type,
 		else
 			DMEMIT("rw ");
 
-		if (dm_cache_metadata_needs_check(cache->cmd))
+		r = dm_cache_metadata_needs_check(cache->cmd, &needs_check);
+
+		if (r || needs_check)
 			DMEMIT("needs_check ");
 		else
 			DMEMIT("- ");
@@ -3806,7 +3814,7 @@ static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits)
 
 static struct target_type cache_target = {
 	.name = "cache",
-	.version = {1, 8, 0},
+	.version = {1, 9, 0},
 	.module = THIS_MODULE,
 	.ctr = cache_ctr,
 	.dtr = cache_dtr,

drivers/md/dm-crypt.c

@@ -1788,7 +1788,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 		goto bad;
 	}
 
-	cc->per_bio_data_size = ti->per_bio_data_size =
+	cc->per_bio_data_size = ti->per_io_data_size =
 		ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start +
 		      sizeof(struct dm_crypt_request) + iv_size_padding + cc->iv_size,
 		      ARCH_KMALLOC_MINALIGN);

drivers/md/dm-delay.c

@@ -204,7 +204,7 @@ out:
 
 	ti->num_flush_bios = 1;
 	ti->num_discard_bios = 1;
-	ti->per_bio_data_size = sizeof(struct dm_delay_info);
+	ti->per_io_data_size = sizeof(struct dm_delay_info);
 	ti->private = dc;
 	return 0;
 

drivers/md/dm-flakey.c

@@ -220,7 +220,7 @@ static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
 	ti->num_flush_bios = 1;
 	ti->num_discard_bios = 1;
-	ti->per_bio_data_size = sizeof(struct per_bio_data);
+	ti->per_io_data_size = sizeof(struct per_bio_data);
 	ti->private = fc;
 	return 0;
 

drivers/md/dm-ioctl.c

@@ -1291,7 +1291,8 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
 
 	immutable_target_type = dm_get_immutable_target_type(md);
 	if (immutable_target_type &&
-	    (immutable_target_type != dm_table_get_immutable_target_type(t))) {
+	    (immutable_target_type != dm_table_get_immutable_target_type(t)) &&
+	    !dm_table_get_wildcard_target(t)) {
 		DMWARN("can't replace immutable target type %s",
 		       immutable_target_type->name);
 		r = -EINVAL;
@@ -1303,7 +1304,7 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
 		dm_set_md_type(md, dm_table_get_type(t));
 
 		/* setup md->queue to reflect md's type (may block) */
-		r = dm_setup_md_queue(md);
+		r = dm_setup_md_queue(md, t);
 		if (r) {
 			DMWARN("unable to set up device queue for new table.");
 			goto err_unlock_md_type;

drivers/md/dm-log-writes.c

@@ -475,7 +475,7 @@ static int log_writes_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	ti->flush_supported = true;
 	ti->num_discard_bios = 1;
 	ti->discards_supported = true;
-	ti->per_bio_data_size = sizeof(struct per_bio_data);
+	ti->per_io_data_size = sizeof(struct per_bio_data);
 	ti->private = lc;
 	return 0;
 

drivers/md/dm-path-selector.h

@@ -50,13 +50,8 @@ struct path_selector_type {
 	/*
 	 * Chooses a path for this io, if no paths are available then
 	 * NULL will be returned.
-	 *
-	 * repeat_count is the number of times to use the path before
-	 * calling the function again.  0 means don't call it again unless
-	 * the path fails.
 	 */
 	struct dm_path *(*select_path) (struct path_selector *ps,
-					unsigned *repeat_count,
 					size_t nr_bytes);
 
 	/*

drivers/md/dm-queue-length.c

@@ -23,12 +23,13 @@
 #include <linux/atomic.h>
 
 #define DM_MSG_PREFIX	"multipath queue-length"
-#define QL_MIN_IO	128
-#define QL_VERSION	"0.1.0"
+#define QL_MIN_IO	1
+#define QL_VERSION	"0.2.0"
 
 struct selector {
 	struct list_head	valid_paths;
 	struct list_head	failed_paths;
+	spinlock_t lock;
 };
 
 struct path_info {
@@ -45,6 +46,7 @@ static struct selector *alloc_selector(void)
 	if (s) {
 		INIT_LIST_HEAD(&s->valid_paths);
 		INIT_LIST_HEAD(&s->failed_paths);
+		spin_lock_init(&s->lock);
 	}
 
 	return s;
@@ -113,6 +115,7 @@ static int ql_add_path(struct path_selector *ps, struct dm_path *path,
 	struct path_info *pi;
 	unsigned repeat_count = QL_MIN_IO;
 	char dummy;
+	unsigned long flags;
 
 	/*
 	 * Arguments: [<repeat_count>]
@@ -129,6 +132,11 @@ static int ql_add_path(struct path_selector *ps, struct dm_path *path,
 		return -EINVAL;
 	}
 
+	if (repeat_count > 1) {
+		DMWARN_LIMIT("repeat_count > 1 is deprecated, using 1 instead");
+		repeat_count = 1;
+	}
+
 	/* Allocate the path information structure */
 	pi = kmalloc(sizeof(*pi), GFP_KERNEL);
 	if (!pi) {
@@ -142,7 +150,9 @@ static int ql_add_path(struct path_selector *ps, struct dm_path *path,
 
 	path->pscontext = pi;
 
+	spin_lock_irqsave(&s->lock, flags);
 	list_add_tail(&pi->list, &s->valid_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return 0;
 }
@@ -151,16 +161,22 @@ static void ql_fail_path(struct path_selector *ps, struct dm_path *path)
 {
 	struct selector *s = ps->context;
 	struct path_info *pi = path->pscontext;
+	unsigned long flags;
 
+	spin_lock_irqsave(&s->lock, flags);
 	list_move(&pi->list, &s->failed_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static int ql_reinstate_path(struct path_selector *ps, struct dm_path *path)
 {
 	struct selector *s = ps->context;
 	struct path_info *pi = path->pscontext;
+	unsigned long flags;
 
+	spin_lock_irqsave(&s->lock, flags);
 	list_move_tail(&pi->list, &s->valid_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return 0;
 }
@@ -168,14 +184,16 @@ static int ql_reinstate_path(struct path_selector *ps, struct dm_path *path)
 /*
  * Select a path having the minimum number of in-flight I/Os
  */
-static struct dm_path *ql_select_path(struct path_selector *ps,
-				      unsigned *repeat_count, size_t nr_bytes)
+static struct dm_path *ql_select_path(struct path_selector *ps, size_t nr_bytes)
 {
 	struct selector *s = ps->context;
 	struct path_info *pi = NULL, *best = NULL;
+	struct dm_path *ret = NULL;
+	unsigned long flags;
 
+	spin_lock_irqsave(&s->lock, flags);
 	if (list_empty(&s->valid_paths))
-		return NULL;
+		goto out;
 
 	/* Change preferred (first in list) path to evenly balance. */
 	list_move_tail(s->valid_paths.next, &s->valid_paths);
@@ -190,11 +208,12 @@ static struct dm_path *ql_select_path(struct path_selector *ps,
 	}
 
 	if (!best)
-		return NULL;
+		goto out;
 
-	*repeat_count = best->repeat_count;
-
-	return best->path;
+	ret = best->path;
+out:
+	spin_unlock_irqrestore(&s->lock, flags);
+	return ret;
 }
 
 static int ql_start_io(struct path_selector *ps, struct dm_path *path,

drivers/md/dm-raid1.c

@@ -1121,7 +1121,7 @@ static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
 	ti->num_flush_bios = 1;
 	ti->num_discard_bios = 1;
-	ti->per_bio_data_size = sizeof(struct dm_raid1_bio_record);
+	ti->per_io_data_size = sizeof(struct dm_raid1_bio_record);
 	ti->discard_zeroes_data_unsupported = true;
 
 	ms->kmirrord_wq = alloc_workqueue("kmirrord", WQ_MEM_RECLAIM, 0);

drivers/md/dm-round-robin.c

@@ -17,6 +17,8 @@
 #include <linux/module.h>
 
 #define DM_MSG_PREFIX "multipath round-robin"
+#define RR_MIN_IO     1000
+#define RR_VERSION    "1.1.0"
 
 /*-----------------------------------------------------------------
  * Path-handling code, paths are held in lists
@@ -41,23 +43,48 @@ static void free_paths(struct list_head *paths)
  * Round-robin selector
  *---------------------------------------------------------------*/
 
-#define RR_MIN_IO		1000
-
 struct selector {
 	struct list_head valid_paths;
 	struct list_head invalid_paths;
+	spinlock_t lock;
+	struct dm_path * __percpu *current_path;
+	struct percpu_counter repeat_count;
 };
 
+static void set_percpu_current_path(struct selector *s, struct dm_path *path)
+{
+	int cpu;
+
+	for_each_possible_cpu(cpu)
+		*per_cpu_ptr(s->current_path, cpu) = path;
+}
+
 static struct selector *alloc_selector(void)
 {
 	struct selector *s = kmalloc(sizeof(*s), GFP_KERNEL);
 
-	if (s) {
-		INIT_LIST_HEAD(&s->valid_paths);
-		INIT_LIST_HEAD(&s->invalid_paths);
-	}
+	if (!s)
+		return NULL;
+
+	INIT_LIST_HEAD(&s->valid_paths);
+	INIT_LIST_HEAD(&s->invalid_paths);
+	spin_lock_init(&s->lock);
+
+	s->current_path = alloc_percpu(struct dm_path *);
+	if (!s->current_path)
+		goto out_current_path;
+	set_percpu_current_path(s, NULL);
+
+	if (percpu_counter_init(&s->repeat_count, 0, GFP_KERNEL))
+		goto out_repeat_count;
 
 	return s;
+
+out_repeat_count:
+	free_percpu(s->current_path);
+out_current_path:
+	kfree(s);
+	return NULL;;
 }
 
 static int rr_create(struct path_selector *ps, unsigned argc, char **argv)
@@ -74,10 +101,12 @@ static int rr_create(struct path_selector *ps, unsigned argc, char **argv)
 
 static void rr_destroy(struct path_selector *ps)
 {
-	struct selector *s = (struct selector *) ps->context;
+	struct selector *s = ps->context;
 
 	free_paths(&s->valid_paths);
 	free_paths(&s->invalid_paths);
+	free_percpu(s->current_path);
+	percpu_counter_destroy(&s->repeat_count);
 	kfree(s);
 	ps->context = NULL;
 }
@@ -111,10 +140,11 @@ static int rr_status(struct path_selector *ps, struct dm_path *path,
 static int rr_add_path(struct path_selector *ps, struct dm_path *path,
 		       int argc, char **argv, char **error)
 {
-	struct selector *s = (struct selector *) ps->context;
+	struct selector *s = ps->context;
 	struct path_info *pi;
 	unsigned repeat_count = RR_MIN_IO;
 	char dummy;
+	unsigned long flags;
 
 	if (argc > 1) {
 		*error = "round-robin ps: incorrect number of arguments";
@@ -139,42 +169,65 @@ static int rr_add_path(struct path_selector *ps, struct dm_path *path,
 
 	path->pscontext = pi;
 
+	spin_lock_irqsave(&s->lock, flags);
 	list_add_tail(&pi->list, &s->valid_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return 0;
 }
 
 static void rr_fail_path(struct path_selector *ps, struct dm_path *p)
 {
-	struct selector *s = (struct selector *) ps->context;
+	unsigned long flags;
+	struct selector *s = ps->context;
 	struct path_info *pi = p->pscontext;
 
+	spin_lock_irqsave(&s->lock, flags);
+	if (p == *this_cpu_ptr(s->current_path))
+		set_percpu_current_path(s, NULL);
+
 	list_move(&pi->list, &s->invalid_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static int rr_reinstate_path(struct path_selector *ps, struct dm_path *p)
 {
-	struct selector *s = (struct selector *) ps->context;
+	unsigned long flags;
+	struct selector *s = ps->context;
 	struct path_info *pi = p->pscontext;
 
+	spin_lock_irqsave(&s->lock, flags);
 	list_move(&pi->list, &s->valid_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return 0;
 }
 
-static struct dm_path *rr_select_path(struct path_selector *ps,
-				      unsigned *repeat_count, size_t nr_bytes)
+static struct dm_path *rr_select_path(struct path_selector *ps, size_t nr_bytes)
 {
-	struct selector *s = (struct selector *) ps->context;
+	unsigned long flags;
+	struct selector *s = ps->context;
 	struct path_info *pi = NULL;
+	struct dm_path *current_path = NULL;
 
+	current_path = *this_cpu_ptr(s->current_path);
+	if (current_path) {
+		percpu_counter_dec(&s->repeat_count);
+		if (percpu_counter_read_positive(&s->repeat_count) > 0)
+			return current_path;
+	}
+
+	spin_lock_irqsave(&s->lock, flags);
 	if (!list_empty(&s->valid_paths)) {
 		pi = list_entry(s->valid_paths.next, struct path_info, list);
 		list_move_tail(&pi->list, &s->valid_paths);
-		*repeat_count = pi->repeat_count;
+		percpu_counter_set(&s->repeat_count, pi->repeat_count);
+		set_percpu_current_path(s, pi->path);
+		current_path = pi->path;
 	}
+	spin_unlock_irqrestore(&s->lock, flags);
 
-	return pi ? pi->path : NULL;
+	return current_path;
 }
 
 static struct path_selector_type rr_ps = {
@@ -198,7 +251,7 @@ static int __init dm_rr_init(void)
 	if (r < 0)
 		DMERR("register failed %d", r);
 
-	DMINFO("version 1.0.0 loaded");
+	DMINFO("version " RR_VERSION " loaded");
 
 	return r;
 }

drivers/md/dm-service-time.c

@@ -19,11 +19,12 @@
 #define ST_MAX_RELATIVE_THROUGHPUT	100
 #define ST_MAX_RELATIVE_THROUGHPUT_SHIFT	7
 #define ST_MAX_INFLIGHT_SIZE	((size_t)-1 >> ST_MAX_RELATIVE_THROUGHPUT_SHIFT)
-#define ST_VERSION	"0.2.0"
+#define ST_VERSION	"0.3.0"
 
 struct selector {
 	struct list_head valid_paths;
 	struct list_head failed_paths;
+	spinlock_t lock;
 };
 
 struct path_info {
@@ -41,6 +42,7 @@ static struct selector *alloc_selector(void)
 	if (s) {
 		INIT_LIST_HEAD(&s->valid_paths);
 		INIT_LIST_HEAD(&s->failed_paths);
+		spin_lock_init(&s->lock);
 	}
 
 	return s;
@@ -111,6 +113,7 @@ static int st_add_path(struct path_selector *ps, struct dm_path *path,
 	unsigned repeat_count = ST_MIN_IO;
 	unsigned relative_throughput = 1;
 	char dummy;
+	unsigned long flags;
 
 	/*
 	 * Arguments: [<repeat_count> [<relative_throughput>]]
@@ -134,6 +137,11 @@ static int st_add_path(struct path_selector *ps, struct dm_path *path,
 		return -EINVAL;
 	}
 
+	if (repeat_count > 1) {
+		DMWARN_LIMIT("repeat_count > 1 is deprecated, using 1 instead");
+		repeat_count = 1;
+	}
+
 	if ((argc == 2) &&
 	    (sscanf(argv[1], "%u%c", &relative_throughput, &dummy) != 1 ||
 	     relative_throughput > ST_MAX_RELATIVE_THROUGHPUT)) {
@@ -155,7 +163,9 @@ static int st_add_path(struct path_selector *ps, struct dm_path *path,
 
 	path->pscontext = pi;
 
+	spin_lock_irqsave(&s->lock, flags);
 	list_add_tail(&pi->list, &s->valid_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return 0;
 }
@@ -164,16 +174,22 @@ static void st_fail_path(struct path_selector *ps, struct dm_path *path)
 {
 	struct selector *s = ps->context;
 	struct path_info *pi = path->pscontext;
+	unsigned long flags;
 
+	spin_lock_irqsave(&s->lock, flags);
 	list_move(&pi->list, &s->failed_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static int st_reinstate_path(struct path_selector *ps, struct dm_path *path)
 {
 	struct selector *s = ps->context;
 	struct path_info *pi = path->pscontext;
+	unsigned long flags;
 
+	spin_lock_irqsave(&s->lock, flags);
 	list_move_tail(&pi->list, &s->valid_paths);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return 0;
 }
@@ -255,14 +271,16 @@ static int st_compare_load(struct path_info *pi1, struct path_info *pi2,
 	return pi2->relative_throughput - pi1->relative_throughput;
 }
 
-static struct dm_path *st_select_path(struct path_selector *ps,
-				      unsigned *repeat_count, size_t nr_bytes)
+static struct dm_path *st_select_path(struct path_selector *ps, size_t nr_bytes)
 {
 	struct selector *s = ps->context;
 	struct path_info *pi = NULL, *best = NULL;
+	struct dm_path *ret = NULL;
+	unsigned long flags;
 
+	spin_lock_irqsave(&s->lock, flags);
 	if (list_empty(&s->valid_paths))
-		return NULL;
+		goto out;
 
 	/* Change preferred (first in list) path to evenly balance. */
 	list_move_tail(s->valid_paths.next, &s->valid_paths);
@@ -272,11 +290,12 @@ static struct dm_path *st_select_path(struct path_selector *ps,
 			best = pi;
 
 	if (!best)
-		return NULL;
+		goto out;
 
-	*repeat_count = best->repeat_count;
-
-	return best->path;
+	ret = best->path;
+out:
+	spin_unlock_irqrestore(&s->lock, flags);
+	return ret;
 }
 
 static int st_start_io(struct path_selector *ps, struct dm_path *path,