1. A flash memory control chip, operating a flash memory in accordance with commands issued from a host, comprising: a first non-volatile storage area; and a microcontroller, storing a root table and a logical-to-physical address mapping relationship between the host and the flash memory in the flash memory, and storing a root table pointer in the first non-volatile storage area, wherein the root table pointer is configured to indicate where the root table is stored in the flash memory; wherein a mapping relationship pointer is set forth in the root table to indicate where the logical-to-physical address mapping relationship is stored in the flash memory; wherein in response to a power restoration request issued from the host, the microcontroller retrieves the logical-to-physical address mapping relationship from the flash memory in accordance with the root table pointer.