3 files changed, 74 insertions, 59 deletions

diff --git a/lib/bitrev.c b/lib/bitrev.c
index 989aff7..3956203 100644
--- a/lib/bitrev.c
+++ b/lib/bitrev.c
@@ -42,10 +42,11 @@ const u8 byte_rev_table[256] = {
 };
 EXPORT_SYMBOL_GPL(byte_rev_table);
 
-static __always_inline u16 bitrev16(u16 x)
+u16 bitrev16(u16 x)
 {
 	return (bitrev8(x & 0xff) << 8) | bitrev8(x >> 8);
 }
+EXPORT_SYMBOL(bitrev16);
 
 /**
  * bitrev32 - reverse the order of bits in a u32 value
diff --git a/lib/div64.c b/lib/div64.c
index bb5bd0c..a111eb8 100644
--- a/lib/div64.c
+++ b/lib/div64.c
@@ -98,3 +98,13 @@ EXPORT_SYMBOL(div64_u64);
 #endif
 
 #endif /* BITS_PER_LONG == 32 */
+
+/*
+ * Iterative div/mod for use when dividend is not expected to be much
+ * bigger than divisor.
+ */
+u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
+{
+	return __iter_div_u64_rem(dividend, divisor, remainder);
+}
+EXPORT_SYMBOL(iter_div_u64_rem);
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index bd52171..169a2f8 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -88,6 +88,57 @@ static inline gfp_t root_gfp_mask(struct radix_tree_root *root)
 	return root->gfp_mask & __GFP_BITS_MASK;
 }
 
+static inline void tag_set(struct radix_tree_node *node, unsigned int tag,
+		int offset)
+{
+	__set_bit(offset, node->tags[tag]);
+}
+
+static inline void tag_clear(struct radix_tree_node *node, unsigned int tag,
+		int offset)
+{
+	__clear_bit(offset, node->tags[tag]);
+}
+
+static inline int tag_get(struct radix_tree_node *node, unsigned int tag,
+		int offset)
+{
+	return test_bit(offset, node->tags[tag]);
+}
+
+static inline void root_tag_set(struct radix_tree_root *root, unsigned int tag)
+{
+	root->gfp_mask |= (__force gfp_t)(1 << (tag + __GFP_BITS_SHIFT));
+}
+
+static inline void root_tag_clear(struct radix_tree_root *root, unsigned int tag)
+{
+	root->gfp_mask &= (__force gfp_t)~(1 << (tag + __GFP_BITS_SHIFT));
+}
+
+static inline void root_tag_clear_all(struct radix_tree_root *root)
+{
+	root->gfp_mask &= __GFP_BITS_MASK;
+}
+
+static inline int root_tag_get(struct radix_tree_root *root, unsigned int tag)
+{
+	return (__force unsigned)root->gfp_mask & (1 << (tag + __GFP_BITS_SHIFT));
+}
+
+/*
+ * Returns 1 if any slot in the node has this tag set.
+ * Otherwise returns 0.
+ */
+static inline int any_tag_set(struct radix_tree_node *node, unsigned int tag)
+{
+	int idx;
+	for (idx = 0; idx < RADIX_TREE_TAG_LONGS; idx++) {
+		if (node->tags[tag][idx])
+			return 1;
+	}
+	return 0;
+}
 /*
  * This assumes that the caller has performed appropriate preallocation, and
  * that the caller has pinned this thread of control to the current CPU.
@@ -124,6 +175,17 @@ static void radix_tree_node_rcu_free(struct rcu_head *head)
 {
 	struct radix_tree_node *node =
 			container_of(head, struct radix_tree_node, rcu_head);
+
+	/*
+	 * must only free zeroed nodes into the slab. radix_tree_shrink
+	 * can leave us with a non-NULL entry in the first slot, so clear
+	 * that here to make sure.
+	 */
+	tag_clear(node, 0, 0);
+	tag_clear(node, 1, 0);
+	node->slots[0] = NULL;
+	node->count = 0;
+
 	kmem_cache_free(radix_tree_node_cachep, node);
 }
 
@@ -165,59 +227,6 @@ out:
 }
 EXPORT_SYMBOL(radix_tree_preload);
 
-static inline void tag_set(struct radix_tree_node *node, unsigned int tag,
-		int offset)
-{
-	__set_bit(offset, node->tags[tag]);
-}
-
-static inline void tag_clear(struct radix_tree_node *node, unsigned int tag,
-		int offset)
-{
-	__clear_bit(offset, node->tags[tag]);
-}
-
-static inline int tag_get(struct radix_tree_node *node, unsigned int tag,
-		int offset)
-{
-	return test_bit(offset, node->tags[tag]);
-}
-
-static inline void root_tag_set(struct radix_tree_root *root, unsigned int tag)
-{
-	root->gfp_mask |= (__force gfp_t)(1 << (tag + __GFP_BITS_SHIFT));
-}
-
-
-static inline void root_tag_clear(struct radix_tree_root *root, unsigned int tag)
-{
-	root->gfp_mask &= (__force gfp_t)~(1 << (tag + __GFP_BITS_SHIFT));
-}
-
-static inline void root_tag_clear_all(struct radix_tree_root *root)
-{
-	root->gfp_mask &= __GFP_BITS_MASK;
-}
-
-static inline int root_tag_get(struct radix_tree_root *root, unsigned int tag)
-{
-	return (__force unsigned)root->gfp_mask & (1 << (tag + __GFP_BITS_SHIFT));
-}
-
-/*
- * Returns 1 if any slot in the node has this tag set.
- * Otherwise returns 0.
- */
-static inline int any_tag_set(struct radix_tree_node *node, unsigned int tag)
-{
-	int idx;
-	for (idx = 0; idx < RADIX_TREE_TAG_LONGS; idx++) {
-		if (node->tags[tag][idx])
-			return 1;
-	}
-	return 0;
-}
-
 /*
  *	Return the maximum key which can be store into a
  *	radix tree with height HEIGHT.
@@ -930,11 +939,6 @@ static inline void radix_tree_shrink(struct radix_tree_root *root)
 			newptr = radix_tree_ptr_to_indirect(newptr);
 		root->rnode = newptr;
 		root->height--;
-		/* must only free zeroed nodes into the slab */
-		tag_clear(to_free, 0, 0);
-		tag_clear(to_free, 1, 0);
-		to_free->slots[0] = NULL;
-		to_free->count = 0;
 		radix_tree_node_free(to_free);
 	}
 }