Data storage device using metadata and mapping table to identify valid user data on non-volatile media

A method of operating a data storage device, the data storage device comprising a non-volatile media comprising a first and a second plurality of physical locations, the first plurality of physical locations storing user data and the non-volatile media storing first metadata associating each of the first plurality of physical locations with a logical block address (LBA), and a mapping table comprising a mapping of each LBA to a current physical location, the method comprising:

• reading the first metadata to obtain a first plurality of LBAs;
• reading the mapping table to determine a current physical location for the first plurality of LBAs;
• and
• comparing the current physical location from the mapping table of each of the first plurality of LBAs to a corresponding one of the first plurality of physical locations to identify valid user data in the first plurality of physical locations for migration into the second plurality of physical locations, wherein the valid user data is user data in a physical location of the first plurality of physical locations that matches the current physical location.