Linux Kernel System V File System Project

History:

The current System V file system driver grew out of the following implementations:
  • Xenix FS - Doug Evans (June 1992)
  • System V FS - Paul B. Monday (March-June 1993)
  • Coherent FS - Bruno Haible (June 1993)
  • AFS/EAFS/EFS - Peter Swain and Krzysztof B. (February 1999) [*]
  • Version 7 FS - Jonathan Naylor (February 1999) [*]
It was merged together and as of today supports:
  • AFS/EAFS/EFS - 512, 1024 and 2048 byte blocks [*]
  • Coherent FS - 1024 byte blocks
  • System V/386 FS - 512, 1024 and 2048 byte blocks
  • Version 7 FS - 1024 byte blocks [*]
  • Xenix FS - 1024 byte blocks
[*] - support available in a separate patch - see below

Known issues:

  • The main difference between stable 2.0.x and development 2.1.x kernels is that the 2.0.x version does not support System V file system with 2048 byte blocks. The backported patch that provides this feature for 2.0.36 kernel is available as sysv-2048-2.0.36.diff, but it should also apply to the latest 2.0.37 pre-patches without any problems. The 2048 byte blocks support has been tested against SCO Unixware 7 System V file system implementation. (mkfs -F s5 -b 2048…)
  • Coherent FS: “free list interleave” is currently ignored. Only file systems with no file system name and no pack name are recognized. See Coherent “man mkfs” for a description of these features.
  • System V Release 2 FS: The superblock is only searched in the blocks 9, 15, 18, which corresponds to the beginning of track 1 on floppy disks. No support for this FS on hard disk yet.

Development:

  • Support for AFS file system. It is similar to System V Release 4, but it is using bitmaps instead of chained free-list of blocks. Extended File Names for System V Release 4 FS and AFS, used in SCO Open Server. These two file systems may be extended to handle filenames up to 255 chars. The similar feature (long file names) also exists in Interactive UNIX (ISC) Version 4.0/3.x System V file system implementation, but I don’t know how it is related to Extended File Names used in SCO. Support for Version 7 file system used on DEC PDP-11. The experimental patch is available here.
  • Unixware disklabel support for 2.0.36 kernel. Like some systems, Unixware uses its own slice table inside a partition (VTOC - Virtual Table of Contents), which format is incompatible with all other OSes. This patch allows you to read VTOC and further mount Unixware partitions under Linux. Tested on x86 machine with SCO Unixware 7 System V file system partitions with 512, 1024, 2048 byte blocks and on SCO Unixware 7 UFS partitions.
  • Support for SCO partitions, also known as ‘divvy’ partitions or divisions is being worked on.

Contributors:

Contact: