Re: "Fix ATAPI transfer lengths" causes CD writing regression

Daniel Drake
2007-10-31T16:34:41Z

Jeff Garzik wrote:
> Jens Axboe wrote:
>> Right, that's of course problematic... There has to be a way to recover
>> that situation though, or you can't export any user command issue
>> facility.
>
> You cannot hope to handle all possible effects arising from an app
> providing an invalid sg header / cdb.

Is it "invalid" though? As a SCSI command, it seems perfectly valid to
ask for less data than the total amount the drive could possibly send.

It's only when we have to translate it to an ATA command in libata that
it becomes invalid there, right?

Are you saying that we should limit the SG_IO commands to only ones that
are valid both as SCSI *and* as their ATA translations? Would that be
for all SCSI devices, or just ones that libata backs?

Daniel