Re: libata equivalent for hdX=remap63

["Alexander E. Patrakov" <patrakov@ums.usu.ru>]

Alan Cox wrote:
> The remap63 hack is ancient. Since the kernel acquired device mapper its
> also unneccessary as you can use device mapper to set up a 63 sector
> offset volume.
>
> I'm amazed anyone is still using it but the right way to handle it on a
> vaguely modern system isn't more kernel hacks but to teach dmraid to
> handle it. If you've got an example of what the layout looks like
> (especially if there is a way to autodetect it) then talk to Heinz (cc'd)
> about getting it added to dmraid.
>   

I got no useful reply to my request for the user to send the first 
megabyte of the hard disk. However, using a cracked version of Hitachi 
OEM variant of OnTrack Disk Manager, I produced a 64GB qemu disk image 
with this disk manager, Windows 98 and a Linux partition (just in case). 
It works fine with hda=remap63 and thus serves the purpose of being an 
example of the layout.

The first 64 KB of this hard disk can be found at 
http://ums.usu.ru/~patrakov/first-64-kb.dsk (please tell me when I can 
remove this file).

The full disk image (obviously, without Windows 98 - but you can install 
it yourself) can be reconstructed as:

dd if=/dev/null of=first-64-kb.dsk bs=1M seek=65536

Note that you can't just reinterpret the OnTrackDM6 partition as a disk 
image because it doesn't start at sector 63. To use this image in qemu:

qemu -hda first-64-kb.dsk -hdachs 1024,16,63,none -cdrom 
your-favourite-livecd.iso

In the original image, I could do a "mount -t vfat -o loop,offset=64512 
/dev/hda /mnt" and see the Windows partition.

-- 
Alexander E. Patrakov