There is no official tool, game, or firmware named "ps3discsfb." Treat any direct download link bearing this keyword with extreme suspicion.
recommends using specific validation tools to check the integrity of game folders. A "verified" dump means all files, including the , match the original retail disc's hash. Recreating the File: ps3discsfb file download verified
You generally do not download this file individually. It is created when you correctly a game from a physical disc. If it is missing from a game folder you downloaded, the game may not be detected by your emulator. There is no official tool, game, or firmware