adding support for msdos logical partitions

Hi,

I would like to add support for msdos logical partitions to wd. Here's
the way I currently have my hard disk partitioned:

                type start finish size
                ------- ----- ------ ----
        c: PRI DOS 0 256 257
                EXT DOS 257 914 658

(the numbers are from memory, so they may be slightly off). Within
the extended partition, I have 3 logical partitions:

                                start finish size
                                ----- ------ ----
        d: 257 513 257
        e: 514 770 257
        f: 771 914 144

It appears that the partition table that resides on block 0 contains a
partition information for the primary and extended dos partitions,
while each logical partition has a partition table of its own.

The question is: what is the best way to modify wd to:

        1) read partition tables from blocks other than block 0?

        2) read multiple partition tables per unit (hard disk)?

It appears that wd only looks for boot block information in sector 0.
Also, init_part() gets a buffer containing boot sector passed to it. To
support logical msdos partitions, it would be nice if init_part() could
(synchronously) read sectors itself.

Suggestions?

                                        Best Regards,

                                        Mike Larson
Received on Thu Sep 2 12:30:08 1993