Henry Nestler wrote:
> It's in our todo/wish list.
> The problem under colinux is, after using partition tables, all block
> devices (hda1, hda2, hda3, ... ) are relative from the sector of
> partition table. In other words a using partition tables need to define
> a file as whole complete disk, not as single partition.
>
> Or we need a transformer for every disk access, that would be transform
> the offset into a filename and a difference offsets.
>
> Currently, the disk access to a partition is a direct access to the
> offset in the file (without recalculation the prameters).
>
>
Option 1:
Make each virtual disk the equivalent to a virtual physical
drive. I have not looked at the colinux disk driver,
But this just means mapping cobd to a single physical
file.I should think that the existing Linux code should take care of
partition tables and properly calculating offsets.
If you want multiple files to correspond to different files
put one partition/file and have the equivalent of hda,hdb.hdc....
The problem with this approach it breaks existing colinux
disk images and systems.
Option 2:
Leave the cobd1,cobd2,.... stuff alone but create a virtual
partition table that is read/written when you access /dev/cobd
the save as if you access /dev/hda. It is more complex.
While you may wish to allow writes to the virtual partition table,
you probably do not really want to use the information that
is written - it would not make much sense to write it in a context
where each file is a different partition.
--
Dave Lynch DLA Systems
Software Development: Embedded Linux
717.627.3770 dhlii@... http://www.dlasys.net
fax: 1.253.369.9244 Cell: 1.717.587.7774
Over 25 years' experience in platforms, languages, and technologies too numerous to list.
"Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction."
Albert Einstein
|