On Mon, 7 Jun 1999 08:22:38 -0700 (PDT) 
 "Eduardo E. Horvath" <eeh@one-o.com> wrote:

 > The problem with solution #3 is that since sub-block accesses to some
 > block devices such as SCSI disks are not possible they may cause the
 > device to lock up.  This needs to be prevented somehow, and if you go
 > with #3 you need to specify how. Solution #2 handles this more gracefully.

The device driver would be able to check to see if the block # is a
multiple of the sector size, and reject the request if necessary.

        -- Jason R. Thorpe <thorpej@nas.nasa.gov>