Method of operating storage controller, storage device, and method of operating storage device to perform copy-block operation based on number of corrected bits

Abstract

A method includes selecting, by a storage controller, a representative page of a first group stored in a first area included in a non-volatile memory device; receiving, by the storage controller, the representative page from the non-volatile memory device; performing, by the storage controller, an error detection operation of determining a number of error bits for the representative page; based on determining that the number of error bits of the representative page exceeds a threshold value, performing an external copy-back operation, by the storage controller, for each page of the first group to a second area included in the non-volatile memory device; and based on determining that the number of error bits of the representative page is less than or equal to the threshold value, performing an internal copy-back operation, by the storage controller, for each page of the first group to the second area.