From mboxrd@z Thu Jan 1 00:00:00 1970 From: Douglas Gilbert Subject: Re: [PATCH RFC] use struct scsi_lun in generic code Date: Tue, 25 Oct 2005 08:40:27 +1000 Message-ID: <435D62DB.1080205@torque.net> References: <20051023043301.GA22615@havoc.gtf.org> <20051024152730.GA28341@us.ibm.com> Reply-To: dougg@torque.net Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: Received: from zorg.st.net.au ([203.16.233.9]:1504 "EHLO borg.st.net.au") by vger.kernel.org with ESMTP id S1751362AbVJXWjX (ORCPT ); Mon, 24 Oct 2005 18:39:23 -0400 In-Reply-To: <20051024152730.GA28341@us.ibm.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Patrick Mansfield Cc: Jeff Garzik , linux-scsi@vger.kernel.org Patrick Mansfield wrote: > Note that current SAM (sam4r02) sort of allows for different sized LUNs, > it says "A logical unit number shall contain 64 bits or 16 bits, with the > size being defined by the SCSI transport protocol. For SCSI transport > protocols that define 16-bit logical unit numbers, the two bytes shall be > formatted as described for the FIRST LEVEL ADDRESSING field (see table 5 > in 4.9.5)." The "or 16 bits" was added to SAM after it was pointed out that a new standard was recently approved that mandated 16 bit luns. That is SBP-3 (i.e. IEEE 1394 transport). All other "current" transports shown in sam4r03.pdf, Annex A are 64 bits (with a note on "SPI-5"). Aside: Annex A shows SPI-5 (Ultra 640) as the "current" SPI standard. This is an example of where standards (or drafts) diverge from reality :-) Doug Gilbert