Apparatus, system, and method for efficient mapping of virtual and physical addresses

A system to efficiently map physical and virtual addresses, the system comprising:

• a data storage device;
• a storage controller controlling data storage on the data storage device, the storage controller comprising:
• a forward mapping module that uses a forward map to identify one or more physical addresses of data of a data segment, the one or more physical addresses identified from one or more virtual addresses of the data segment, the data segment identified in a storage request directed to the data storage device, the forward map comprising a map of one or more virtual addresses to one or more physical addresses of data stored in the data storage device, the one or more virtual addresses comprising discrete addresses within a virtual address space wherein the virtual addresses sparsely populate the virtual address space;
• a reverse mapping module that uses a reverse map to determines a virtual address of a data segment from a physical address, wherein the reverse map maps the one or more physical addresses to one or more virtual addresses, the physical addresses in the reverse map associated with the forward map, the one or more virtual addresses corresponding to one or more data segments relating to the data stored in the data storage device, the reverse map mapping the data storage device into erase regions such that a portion of the reverse map spans an erase region of the data storage device erased together during a storage space recovery operation, the storage space recovery operation recovering erase regions for future storage of data;
• and
• a storage space recovery module that uses the reverse map to identify valid data in an erase region prior to an operation to recover the erase region, the identified valid data moved to another erase region prior to the recovery operation.

A method, comprising:

• using a forward map to identify one or more physical addresses of data of a data segment, the one or more physical addresses identified from one or more virtual addresses of the data segment, the data segment identified in a storage request directed to a data storage device, the forward map comprising a map of one or more virtual addresses to one or more physical addresses of data stored in the data storage device, the one or more virtual addresses comprising discrete addresses within a virtual address space wherein the virtual addresses sparsely populate the virtual address space;
• using a reverse map to determine a virtual address of a data segment from a physical address, wherein the reverse map maps the one or more physical addresses to one or more virtual addresses, the physical addresses in the reverse map associated with the forward map, the one or more virtual addresses corresponding to one or more data segments relating to the data stored in the data storage device, the reverse map mapping the data storage device into erase regions such that a portion of the reverse map spans an erase region of the data storage device erased together during a storage space recovery operation, the storage space recovery operation recovering erase regions for future storage of data;
• and
• using the reverse map to identify valid data in an erase region prior to an operation to recover the erase region, the identified valid data moved to another erase region prior to the recovery operation.