/*
* tree can be full, so it would need to grow in depth:
- * allocation + old root + new root
+ * we need one credit to modify old root, credits for
+ * new root will be added in split accounting
*/
- needed += 2 + 1 + 1;
+ needed += 1;
/*
* Index split can happen, we would need:
* allocate intermediate indexes (bitmap + group)
* + change two blocks at each level, but root (already included)
*/
- needed = (depth * 2) + (depth * 2);
+ needed += (depth * 2) + (depth * 2);
/* any allocation modifies superblock */
needed += 1;