From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roland Dreier Subject: Re: [RFC][PATCH 1/1] cxgb3i: cxgb3 iSCSI initiator Date: Wed, 13 Aug 2008 16:03:15 -0700 Message-ID: References: <20080811.145313.178992274.davem@davemloft.net> <20080813.150831.193391799.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: rick.jones2@hp.com, jgarzik@pobox.com, swise@opengridcomputing.com, divy@chelsio.com, kxie@chelsio.com, netdev@vger.kernel.org, open-iscsi@googlegroups.com, michaelc@cs.wisc.edu, daisyc@us.ibm.com, wenxiong@us.ibm.com, bhua@us.ibm.com, dm@chelsio.com, leedom@chelsio.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org To: David Miller Return-path: Received: from sj-iport-6.cisco.com ([171.71.176.117]:41109 "EHLO sj-iport-6.cisco.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754268AbYHMXDR (ORCPT ); Wed, 13 Aug 2008 19:03:17 -0400 In-Reply-To: <20080813.150831.193391799.davem@davemloft.net> (David Miller's message of "Wed, 13 Aug 2008 15:08:31 -0700 (PDT)") Sender: netdev-owner@vger.kernel.org List-ID: > Like I said, you retain a "flow cache" (say it a million times, "flow > cache") that remembers the current parameters and the buffers > currently assigned to that flow and what offset within those buffers. 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. 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. - R.