[PATCH] rbtree: fixed reversed RB_EMPTY_NODE and rb_next/prev

The conditions got reserved. Also make rb_next() and rb_prev() check
for the empty condition.

Signed-off-by: Jens Axboe <axboe@suse.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/lib/rbtree.c b/lib/rbtree.c
index 1e55ba1c2edf..48499c2d88cc 100644
--- a/lib/rbtree.c
+++ b/lib/rbtree.c
@@ -322,6 +322,9 @@ struct rb_node *rb_next(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) {
@@ -348,6 +351,9 @@ struct rb_node *rb_prev(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) {