Re: blocksizes

[Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>]

> > >FYI, Windows XP creates MBR in the first sector even on a removable
> > >2KB/sec MO disk and it seems to use physical block numbers.
> > 
> > I haven't found an official spec for MBR on non-512byte blocks, but
> > so far everyone seems to use the first 512 bytes from LBA 0.
> 
> That is my suspicion - which probably means most of the boot code doesn't
> know about the actual sector size!

I wonder if there was other possible scenario..

Anyway, if BIOS (or firmware) uses bytes (or other different units
from one for LBA in MBR) for I/O strategy, we have to know sectorsize.

> Netbsd's fdisk could be changed to do 8k reads (as I changed installboot).
> But that might cause a problem is there are insufficient unused sectors
> before the first partition (or next partition for the extended partition
> list).

fdisk(8) should know hardware sector size anyway.
Otherwize it can't calculate LBA in the sector size
from partition size in MB or GB.
---
Izumi Tsutsui