Soren Schmidt <[EMAIL PROTECTED]> wrote:

> Another thing is that for this to work, the drive has to be set into
> a 32.5Kb block mode where the 32K carry userdata, and the 512bytes
> carry block info, like blocknumber etc, since you have to have
> that info when reading, since you must keep track of which blocks
> you have read, since they might be repeated later due to bad spots
> and the above hit'n'write strategy left one double block around...
> 
> So, since I have not found a way to deal with this in a satisfactory
> way (malloc'ing 1 Mbyte worth of buffer in the kernel is not fun), the
> support we have can't handle tapes with bad spots on it...

     Does the ata device have something analogous to the SCSI
passthrough device (e.g., /dev/pass0)?  A long time ago, when I was
looking at implementing a "driver" for the SCSI version of the Onstream
drive, it was much easier to write a userland "driver" that used the
passthrough device.  This way, you can malloc() as much space as you
want (the real reason I did it that way, was because it could be much
easier to port to other operating systems).

-- 
        Darryl Okahata
        [EMAIL PROTECTED]

DISCLAIMER: this message is the author's personal opinion and does not
constitute the support, opinion, or policy of Agilent Technologies, or
of the little green men that have been following him all day.


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