libnvdimm: replace mutex_is_locked() warnings with lockdep_assert_held

For warnings that should only ever trigger during development and
testing replace WARN statements with lockdep_assert_held. The lockdep
pattern is prevalent, and these paths are are well covered by libnvdimm
unit tests.
Reported-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

drivers/nvdimm/claim.c

@@ -22,9 +22,8 @@ void __nd_detach_ndns(struct device *dev, struct nd_namespace_common **_ndns)
 {
 	struct nd_namespace_common *ndns = *_ndns;
 
-	dev_WARN_ONCE(dev, !mutex_is_locked(&ndns->dev.mutex)
-			|| ndns->claim != dev,
-			"%s: invalid claim\n", __func__);
+	lockdep_assert_held(&ndns->dev.mutex);
+	dev_WARN_ONCE(dev, ndns->claim != dev, "%s: invalid claim\n", __func__);
 	ndns->claim = NULL;
 	*_ndns = NULL;
 	put_device(&ndns->dev);
@@ -49,9 +48,8 @@ bool __nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach,
 {
 	if (attach->claim)
 		return false;
-	dev_WARN_ONCE(dev, !mutex_is_locked(&attach->dev.mutex)
-			|| *_ndns,
-			"%s: invalid claim\n", __func__);
+	lockdep_assert_held(&attach->dev.mutex);
+	dev_WARN_ONCE(dev, *_ndns, "%s: invalid claim\n", __func__);
 	attach->claim = dev;
 	*_ndns = attach;
 	get_device(&attach->dev);

drivers/nvdimm/namespace_devs.c

@@ -1653,7 +1653,7 @@ static int select_pmem_id(struct nd_region *nd_region, u8 *pmem_id)
 		u64 hw_start, hw_end, pmem_start, pmem_end;
 		struct nd_label_ent *label_ent;
 
-		WARN_ON(!mutex_is_locked(&nd_mapping->lock));
+		lockdep_assert_held(&nd_mapping->lock);
 		list_for_each_entry(label_ent, &nd_mapping->labels, list) {
 			nd_label = label_ent->label;
 			if (!nd_label)

drivers/nvdimm/region_devs.c

@@ -509,7 +509,7 @@ void nd_mapping_free_labels(struct nd_mapping *nd_mapping)
 {
 	struct nd_label_ent *label_ent, *e;
 
-	WARN_ON(!mutex_is_locked(&nd_mapping->lock));
+	lockdep_assert_held(&nd_mapping->lock);
 	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
 		list_del(&label_ent->list);
 		kfree(label_ent);