nlm4svc_set_file_lock_range
nlm4svc_set_file_lock_range(fl, l_offset, l_len);
nlm4svc_set_file_lock_range(fl, lock->lock_start, lock->lock_len);
void nlm4svc_set_file_lock_range(struct file_lock *fl, u64 off, u64 len);