Re: [RFC][PATCH 1/1] cxgb3i: cxgb3 iSCSI initiator

[David Miller <davem@davemloft.net>]

From: Roland Dreier <rdreier@cisco.com>
Date: Wed, 13 Aug 2008 16:03:15 -0700

> OK, I admit you could make something work -- add hooks for the low-level
> driver to ask the iSCSI initiator where PDU boundaries are so it can
> resync when something is evicted from the flow cache, have the initiator
> format its tags in a special way to encode placement data, etc, etc.
> The scheme does bring to mind Alan's earlier comment about pigs and
> propulsion, though.

There would need to be _NO_ hooks into the iSCSI initiator at all.

The card would land the block I/O data onto the necessary page boundaries
and the iSCSI code would just be able to thus use the pages directly
and as-is.

It would look perfectly like normal TCP receive traffic.  No hooks,
no special cases, nothing like that.

> In any case, as I said in the part of my email that you snipped, the
> real issue is not designing hypothetical hardware, but deciding how to
> support the Chelsio, Broadcom, etc hardware that exists today.

The same like we support TOE hardware that exists today.  That is, we
don't.