Subject: Re: Disklabel ioctls (was Re: nore on disk ...)
To: Ty Sarna <tsarna@endicor.com>
From: Waldi Ravens <waldi@moacs.indiv.nl.net>
List: tech-kern
Date: 11/16/1995 16:44:04
Ty Sarna wrote:

> And is there a reason NetBSD partions aren't made as individual
> partitions in the DOS partition table?)

I don't know about the i386-port, but in this respect the situation
is similar for the atari-port. The NetBSD disk label partitions do
not necesseraly have to be defined as AHDI (vendor specific format)
partitions. The main reason for this is that NetBSDs disk label is
more flexible than the AHDI partition table (actually it's a linked
list of partitions), and it's much easier to modify NetBSDs disk
label.

Of course it is also possible to use disks which do not contain an
AHDI partition table. I don't know if such disks could be used under
different NetBSD ports. Their structure is very simple: an 8KB boot
block is located at block zero, boot_block[0..7167] contains the
primary and secondary boot loaders, boot_block[7168..8191] contains
the disk label.

I believe that, if support is added for all the vendor specific disk
formats of currently supported platforms, it should be configurable.
Otherwise it just adds a lot of hardly ever (or never) used code to
the kernel. If, for example, in the current situation, I throw the
AHDI compatibilty code out of disksubr.c, the size of the *disklabel()
functions will decrease some 75-85%.


Waldi