Adaptive control of Input/Output (I/O) operations in a data storage system is provided to enable efficient use of the data storage system. More specifically, an interface is provided in order to adaptively control I/O operations to the data storage system. The interface receives a data request. The interface mediates with the data storage system and employs a handle which references one or more files. The handle designates how to process the data request associated with the referenced one or more files. The interface supports execution of the data request in accordance with the handle. Accordingly, the interface provides adaptive direct management of the data storage system at file granularity and/or at data request granularity as designated in the handle(s).