1. An apparatus, comprising: a data storage device having first storage space configured to store first data, the first data stored with opportunistic retention that is unavailable for access by an application when the first storage space is reallocated by a storage management module resulting in permanent loss of the first data; the data storage device having second storage space configured to store second data, the second data stored with guaranteed retention that is available for access by the application until the application overwrites the second storage space; and a processor coupled to a memory and configured to execute the application and the storage management module, the storage management module when executed operable to: receive a request from the application to store first new data on the data storage device, determine that there is not an amount of free storage space on the data storage device to store the first new data, discard a first portion of the first data with the opportunistic retention stored at a selected storage location in the first storage space resulting in the permanent loss of the first portion of the first data, store the first new data at the selected storage location in the first storage space upon discarding the first portion of the first data, and convert the selected storage location in the first storage space that stores the first new data from the opportunistic retention to the guaranteed retention such that the first new data stored in the converted selected storage location cannot be discarded to store subsequent opportunistic data.