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Pat LaVarre wrote:
The only thing I care about is the 16-byte CDB limit currently in Linux...
If we take advantage of the extra four bytes there, we will not design a solution usable by the max-12-CDB-byte connections, in particular normal PATAPI, that also wish to give ATA pass thru to hosts that think they support only SCSI pass thru. Those people will therefore push to revisit this issue, yet again.
No. I think you are missing some context...
This opcode is used to tunnel through a _fake_ SCSI layer to reach a real ATA device behind it.
ATAPI does not come into play here. This "ata passthru" opcode is only needed for ATA. For ATAPI, one does not need to pass through a fake SCSI layer, but rather avoid the hardware device's SCSI layer and talk directly to ATA. Subtle difference... but substantial.
Jeff
