File-System Structure File structure Logical storage unit Collection of related informationapplication programs ↓ FS resides on secondary storage File name logical file system (disks) ↓ FS organization Logical block address file-organization module How FS should look to the user ↓ Physical block address How to map the logical FS onto basic file system the physical secondary-storage ↓ Issue commands to l/O to retrieve physical block devices l/O control FS organized into layers Hardware-specific instructions devices Figure:Layered File System 口”48+4在4色”主)QC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . File-System Structure ▶ File structure ▶ Logical storage unit ▶ Collection of related information ▶ FS resides on secondary storage (disks) ▶ FS organization ▶ How FS should look to the user ▶ How to map the logical FS onto the physical secondary-storage devices ▶ FS organized into layers application programs File name logical file system Logical block address file-organization module Physical block address basic file system Issue commands to I/O to retrieve physical block I/O control Hardware-specific instructions devices Figure: Layered File System