diff --git a/lib/idr.c b/lib/idr.c
index 16d2143..7185353 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -33,7 +33,7 @@
 #include <linux/string.h>
 #include <linux/idr.h>
 
-static kmem_cache_t *idr_layer_cache;
+static struct kmem_cache *idr_layer_cache;
 
 static struct idr_layer *alloc_layer(struct idr *idp)
 {
@@ -445,7 +445,7 @@
 }
 EXPORT_SYMBOL(idr_replace);
 
-static void idr_cache_ctor(void * idr_layer, kmem_cache_t *idr_layer_cache,
+static void idr_cache_ctor(void * idr_layer, struct kmem_cache *idr_layer_cache,
 		unsigned long flags)
 {
 	memset(idr_layer, 0, sizeof(struct idr_layer));
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index aa9bfd0..9eb2595 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -63,7 +63,7 @@
 /*
  * Radix tree node cache.
  */
-static kmem_cache_t *radix_tree_node_cachep;
+static struct kmem_cache *radix_tree_node_cachep;
 
 /*
  * Per-cpu pool of preloaded nodes
@@ -846,7 +846,7 @@
 EXPORT_SYMBOL(radix_tree_tagged);
 
 static void
-radix_tree_node_ctor(void *node, kmem_cache_t *cachep, unsigned long flags)
+radix_tree_node_ctor(void *node, struct kmem_cache *cachep, unsigned long flags)
 {
 	memset(node, 0, sizeof(struct radix_tree_node));
 }