A read and write method includes: applying a read command to a memory device, the read command indicating address information; reading data to be read from a storage unit corresponding to the address information indicated by the read command; and if an error occurs in the data to be read, associating the address information indicated by the read command with a spare storage unit, and backing up the address information indicated by the read command and association information between the address information and the spare storage unit in a non-volatile storage unit based on a preset rule.