dm bufio: clean up rbtree block ordering

dm-bufio uses unnatural ordering in the rb-tree - blocks with smaller
numbers were put to the right node and blocks with bigger numbers were
put to the left node.

Reverse that logic so that it's natural.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index 993e624..ff19add 100644 (file)
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -256,7 +256,7 @@ static struct dm_buffer *__find(struct dm_bufio_client *c, sector_t block)
                if (b->block == block)
                        return b;
 
-               n = (b->block < block) ? n->rb_left : n->rb_right;
+               n = block < b->block ? n->rb_left : n->rb_right;
        }
 
        return NULL;
@@ -276,8 +276,8 @@ static void __insert(struct dm_bufio_client *c, struct dm_buffer *b)
                }
 
                parent = *new;
-               new = (found->block < b->block) ?
-                       &((*new)->rb_left) : &((*new)->rb_right);
+               new = b->block < found->block ?
+                       &found->node.rb_left : &found->node.rb_right;
        }
 
        rb_link_node(&b->node, parent, new);