Re: WD_QUIRK_FORCE_LBA48

[David Laight <david%l8s.co.uk@localhost>]

On Wed, Dec 16, 2009 at 11:41:47AM -0800, Brian Buhrow wrote:
>       Hello.  Under NetBSD-5 I'm using my Ipod shuffle with 2048 byte
> sectors without a problem.  So, I think the problem has been partially
> addressed, at least.

Some support is there - for FAT on USB sticks.
(USB sticks with 2k sectors are relatively easy to find, they often have
a MP3 player 'feature'.)

Hovever more general support is more problematic!

My preference would be to hide the physical sector size from almost
all of the code.

This would leave DEV_BSIZE as the constant 512.

The sector size in the label would just refer to the sector numbers
used in the label - and might differ from the physical one!
Filesystems should be physical sector size agnostic - making is possible
to image copy between disks with different physical sector sizes.

Clearly a disk read would have to be a whole number of physical sectors,
but that can be policed in the driver itself.

Certainly all the code in the wd driver that is looking at sector sizes
should be using a value obtained from the disk identify request, not
the disklabel.

I'm not at all sure how the patches lurking in various PR intend to work!

        David

-- 
David Laight: david%l8s.co.uk@localhost