Subject: Re: [PATCH v2 2/2] Crypto: Talitos: Support for=20
Async_tx XOR offload

Ira W. Snyder wrote:

quoted

Yes, I have used the device_prep_dma_interrupt()=20

functionality quite a=20

quoted

while back. However, I found it to be pretty much useless.

The specific case it is needed for Talitos/raid is a channel=20
switch interrupt.  The interrupt causes the cleanup operation=20
to be run which will kick off any pending dependent operations=20
on the xor channel.  In the raid case we only have callbacks=20
at the end of a chain, so we need the interrupt to kick the=20
engine in an operation chain like=20
xor->copy->xor->callback.

I am wondering if can use more callbacks to kick off pending dependent =
operations?
Like xor->callback->copy->callback->xor->callback?

- Leo