+ struct rw_semaphore ic_sem;
+ struct dynlock ic_tree_lock;
+ /*
+ * Protect ic_idle_bh
+ */
+ struct semaphore ic_idle_sem;
+ /*
+ * BH for idle blocks
+ */
+ struct buffer_head *ic_idle_bh;
+ unsigned int ic_idle_failed:1; /* Idle block mechanism failed */