question for ext2 fs gurus

[Alexei Nefediev <nefediev heron itep ru>]

Hello,

I have a very specific question for those who understand ext2 fylesystem
logic very well. I have 3.2Gb HDD. Unfortunately I made a mistake and
created one large extended partiton which covers all 3.2Gb and several
logical partitions inside of it. This turns out very inconvenient as
partitions inside of extended one are not recognized by some OS, for
example. In short, I would like to rebuild the partition table so that
several primary ones were added. The task would be quite easy if I had any
good backup for Linux installed on this HDD. But I do not. :( So I would
like to rebuild partions but not to lose information on this HDD.

I see the only possibility to do this by creating new partitions exactly
on the places where old ones were. For example, if I had logical
partition from 198 cylinder up to 566, then the new primary partition will
begin and end just with the same numbers. Sure I won't format the new
partitions. I wonder whether this will work? I've played with fdisk a
little and noticed that primary and logical partitions which start and end
at the same cylinders have different sizes in blocks. Will this hurt?

Any other idea's will be highly appreciated.
Thanks in advance,
Alexei