+bool bch2_bucket_nocow_is_locked(struct bucket_nocow_lock_table *, struct bpos);
+void bch2_bucket_nocow_unlock(struct bucket_nocow_lock_table *, struct bpos, int);
+bool __bch2_bucket_nocow_trylock(struct nocow_lock_bucket *, u64, int);
+void __bch2_bucket_nocow_lock(struct bucket_nocow_lock_table *,
+ struct nocow_lock_bucket *, u64, int);