Data storage device, memory controller and method of operating the same

A data storage device includes a storage and a memory controller. The storage is configured to store data. The memory controller generates meta-data including a mapping relationship between a logical address used in an external device and a physical address used in the storage. The memory controller generates a normal meta-slice having a first size including the meta-data in a first operation mode. The memory controller stores a meta-page including the normal meta-slice in the storage. The memory controller generates a modified meta-slice having a second size as a part of the normal meta-slice in the second operation mode. The memory controller stores a meta-page including the modified meta-slice and context data corresponding to size information of the modified meta-slice in the storage. The memory controller restores the meta-data based on the context data in a power-on mode.