[PATCH RFCv1 1/2] dmaengine: add support for scatterlist to scatterlist transfers
Dan Williams
dan.j.williams at intel.com
Sat Sep 25 08:20:14 EST 2010
On Fri, 2010-09-24 at 15:04 -0700, Ira W. Snyder wrote:
> On Fri, Sep 24, 2010 at 02:53:14PM -0700, Dan Williams wrote:
> > What about overrun or underrun do we not care if src_total != dst_total?
> >
> > Otherwise looks ok.
> >
>
> I don't know if we should care about that. The algorithm handles that
> case just fine. It copies the maximum amount it can, which is exactly
> min(src_total, dst_total). Whichever scatterlist runs out of entries
> first is the shortest.
>
> As a real world example, my driver verifies that both scatterlists have
> exactly the right number of bytes available before trying to program the
> hardware.
Ok, just handle the prep failure and I think we are good to go.
--
Dan
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