FsRecovery

Overview

This PEIM implements file system-based BIOS recovery during the PEI phase. At 77 functions, it is the largest of the PEI recovery modules. It provides file system drivers and recovery media access logic for discovering and loading recovery capsule images from formatted volumes (FAT partitions on disks or USB media). It handles media enumeration, file system volume opening, and file read operations within the constrained PEI environment.

Key Functions

• ModuleEntryPoint -- UEFI PEI entry point, dispatches to FsRecovery logic
• Recovery media detection and file system volume enumeration
• Recovery image file discovery and reading from FAT-formatted media
• ZeroMem / CopyMem / SetMem / SetMem32 -- Memory utility functions (77 total functions)

Dependencies

• FsRecovery.h (module header)
• PEI Services (FV enumeration, file lookup, memory allocation)
• Block I/O PPI (for disk/USB media access)
• Disk I/O PPI (sector-level I/O)
• FAT file system driver (PEI phase)

Platform

• Architecture: IA32 (32-bit)
• Machine type: x86 (0x014C)
• Subsystem: EFI Boot Service Driver (0x000B)
• Format: PE32
• Sections: .text (16KB), .rdata (2KB), .data, .reloc