Mounting ext3fs partition

[Josh Carroll]

> Hi josh,
>
> Exactly, it is 256. So according to you, I can't use the mounted
> filesystem, right?
>
> Could you please explain in more detail, what the problem is?
>
> Thanks in advance.

I believe around e2fsprogs version 1.40.5 or so, they changed the
default inode size from 128 to 256. The current ext2fs driver in
FreeBSD has a hard-coded inode size defined:

#define EXT2_INODE_SIZE            128

I have a patch that dynamically determines this size, but I do not yet
have a good enough understanding of the ext2/3 spec to decide if the
changes I made are sufficient to fix the problem or if there is some
risk of breakage because the extra 128 is required for some metadata
of some sort.

What happened in your case is something I was afraid of and what
prompted me to look into a fix in the first place - namely, newer
Linux distributions or even file systems created by e2fsprogs from
ports in FreeBSD will be unusable with the current ext2fs driver,
since it assumes a size of 128.

There is some more information here regarding the patch and its current status:

http://unix.derkeiler.com/Mailing-Lists/FreeBSD/stable/2008-11/msg00421.html

I (or even better, someone more knowledgeable about file systems) need
to read through the ext2/3 spec and determine if the changes I've made
cause any breakage.

Thanks,
Josh