Re: Implementing UFS2 Filesystem Support

[Robert Millan]

Hi!

> I've been wanting to try out the latest FreeBSD 5-CURRENT series, and so far
> the only thing holding me back is I can't use my favorite bootloader (GRUB)
> with it. So, I have a little programming experience and would like to
> implement it if possible. I did a little checking around and I found that
> (from a reading standpoint) UFS2 is merely UFS with 64-bit addressing, and
> that the FFS directory structure layer on top of that was unchanged. Thus,
> this seems to be a relatively easy fix. I hope ;-) So, if anyone is reading
> this, please point me in the right direction for what files in GRUB I should
> be looking at. Thanks.

You basicaly need to write a stage2/ufs2.h and a stage2/fsys_ufs2.c. Maybe
you can use the FFS files as a base or even make it into a single file
that compiles both filesystems with the proper CPP defines.

You also have to add the filesystem support in the places where other
filesystems are (grep for the name of one of them, say, "grep -i reiserfs"
to see what you need). E.g:

configure.in
stage2/builtins.c
stage2/disk_io.c
stage2/filesys.h
stage2/Makefile.am
stage2/shared.h
stage2/size_test

If that helps, you can look at my update of Kurt Skauen's patch to
support AFS:

  http://people.debian.org/~rmh/grub.diff

Beware that this patch also adds support for running GRUB on AtheOS. The
changes you're interested in are only configure.in and the stuff in stage2/
directory.

-- 
Robert Millan