Re: SCSI TMF processing; tag allocation

From: Matthew Wilcox
Date: Mon Nov 15 2010 - 14:09:11 EST


On Mon, Nov 15, 2010 at 01:53:28PM -0500, Douglas Gilbert wrote:
> On the subject of UAS, due to some USB-3 streaming protocol
> requirements, three tag values cannot be used by SCSI. They
> are 0h, FFFEh and FFFFh. So those available for SCSI tag
> use are 1h to FFFDh inclusive.

I add 1 to the tag value handed to me by the block layer, and use that
as the tag value that I tell the UAS device this command has. So if I
ask for 256 tags, I'll hand values 1-257 to the device.

--
Matthew Wilcox Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours. We can't possibly take such
a retrograde step."
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/