X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=lib%2Frbtree.c;h=9956b99649f02af0667666e098449f9df38d26b4;hb=bca794785c2c12ecddeb09e70165b8ff80baa6ae;hp=1e55ba1c2edfac510c41c87e47e7849f99a5f3b3;hpb=c0bc8721b8d0380ec69fa97578c91201201b05a9;p=linux-2.6-omap-h63xx.git

diff --git a/lib/rbtree.c b/lib/rbtree.c
index 1e55ba1c2ed..9956b99649f 100644
--- a/lib/rbtree.c
+++ b/lib/rbtree.c
@@ -292,7 +292,7 @@ EXPORT_SYMBOL(rb_erase);
 /*
  * This function returns the first node (in sort order) of the tree.
  */
-struct rb_node *rb_first(struct rb_root *root)
+struct rb_node *rb_first(const struct rb_root *root)
 {
 	struct rb_node	*n;
 
@@ -305,7 +305,7 @@ struct rb_node *rb_first(struct rb_root *root)
 }
 EXPORT_SYMBOL(rb_first);
 
-struct rb_node *rb_last(struct rb_root *root)
+struct rb_node *rb_last(const struct rb_root *root)
 {
 	struct rb_node	*n;
 
@@ -318,17 +318,20 @@ struct rb_node *rb_last(struct rb_root *root)
 }
 EXPORT_SYMBOL(rb_last);
 
-struct rb_node *rb_next(struct rb_node *node)
+struct rb_node *rb_next(const struct rb_node *node)
 {
 	struct rb_node *parent;
 
+	if (rb_parent(node) == node)
+		return NULL;
+
 	/* If we have a right-hand child, go down and then left as far
 	   as we can. */
 	if (node->rb_right) {
 		node = node->rb_right; 
 		while (node->rb_left)
 			node=node->rb_left;
-		return node;
+		return (struct rb_node *)node;
 	}
 
 	/* No right-hand children.  Everything down and left is
@@ -344,17 +347,20 @@ struct rb_node *rb_next(struct rb_node *node)
 }
 EXPORT_SYMBOL(rb_next);
 
-struct rb_node *rb_prev(struct rb_node *node)
+struct rb_node *rb_prev(const struct rb_node *node)
 {
 	struct rb_node *parent;
 
+	if (rb_parent(node) == node)
+		return NULL;
+
 	/* If we have a left-hand child, go down and then right as far
 	   as we can. */
 	if (node->rb_left) {
 		node = node->rb_left; 
 		while (node->rb_right)
 			node=node->rb_right;
-		return node;
+		return (struct rb_node *)node;
 	}
 
 	/* No left-hand children. Go up till we find an ancestor which