Patent ID: 8006038

Claim:
A method of storing data in a usage block of a disk drive to indicate usage data of the disk drive comprising; Querying the disk drive for size wherein size comprises a total number of logical blocks on the disk drive; Receiving a size response wherein the size comprises a total number of logical blocks on the disk drive; Determining the number of usage blocks necessary to represent the number of logical blocks on the disk drive; and Storing usage data in the usage blocks, wherein the logical blocks are individually addressable and accessible n*512 byte blocks where n is a positive integer; determining the first address for the usage block by subtracting the needed usage blocks by 1 from the total number of block on the disk drive; determining the usage block for a particular transfer comprising: determine the start logical block address of the transfer; divide the start logical block address by the number of blocks that fit into a byte to obtain a start block number; divide the start block number by the number of bytes in a block that can store usage data to obtain the usage block number; adding the usage block number to the first usage block to determine the start usage block; and modulo the start block number by the number of bytes in a block that can store usage data to obtain the byte in the usage block that represents the start of the transfer.