1. A machine implemented method, comprising: mapping a plurality of virtual hard drives to a logical unit number (LUN) of a storage system, each virtual hard drive including a logical block address (LBA) range of the storage system LUN; storing the mapping in a caching module data structure; determining that one of the virtual hard drives should be cached; and updating the caching module data structure to indicate that the LBA range associated with the one of the virtual hard drives should be cached.