From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [RFC][PATCH 1/1] cxgb3i: cxgb3 iSCSI initiator Date: Wed, 13 Aug 2008 19:05:21 -0700 (PDT) Message-ID: <20080813.190521.224523380.davem@davemloft.net> References: <48A389DB.9050002@opengridcomputing.com> <20080813.183755.72334968.davem@davemloft.net> <48A38FEF.6090500@opengridcomputing.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: tom@opengridcomputing.com, rdreier@cisco.com, rick.jones2@hp.com, jgarzik@pobox.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: swise@opengridcomputing.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:44281 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751164AbYHNCFT (ORCPT ); Wed, 13 Aug 2008 22:05:19 -0400 In-Reply-To: <48A38FEF.6090500@opengridcomputing.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Steve Wise Date: Wed, 13 Aug 2008 20:52:47 -0500 > How do you envision programming such a device? There should be no special programming. > It will need TCP and iSCSI state to have any chance of doing useful > and productive placement of data. The card can see the entire TCP stream, it doesn't need anything more than that. It can parse every packet header, see what kind of data transfer is being requested or responded to, etc. Look, I'm not going to design this whole friggin' thing for you guys. I've stated clearly what the base requirement is, which is that the packet is fully processed by the networking stack and that the card merely does data placement optimizations that the stack can completely ignore if it wants to. You have an entire engine in there that can interpret an iSCSI transport stream, you have the logic to do these kinds of things, and it can be done without managing the connection on the card.