From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: PMP and SEMB messages to SEP Date: Tue, 25 Jan 2011 09:14:14 -0500 Message-ID: <1295964854.4955.21.camel@mulgrave.site> References: <20110113192558.GE16039@MAIL.13thfloor.at> <20110114142018.GA978@htj.dyndns.org> <20110114165957.GH16039@MAIL.13thfloor.at> <20110114170407.GE978@htj.dyndns.org> <20110114173759.GI16039@MAIL.13thfloor.at> <20110117154042.GG27123@htj.dyndns.org> <1295281131.3015.44.camel@mulgrave.site> <20110117171836.GI27123@htj.dyndns.org> <1295284906.3015.136.camel@mulgrave.site> <20110117172415.GK27123@htj.dyndns.org> <20110125030740.GB24024@MAIL.13thfloor.at> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from cantor2.suse.de ([195.135.220.15]:51585 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753742Ab1AYOOS (ORCPT ); Tue, 25 Jan 2011 09:14:18 -0500 In-Reply-To: <20110125030740.GB24024@MAIL.13thfloor.at> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Herbert Poetzl Cc: Tejun Heo , linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org On Tue, 2011-01-25 at 04:07 +0100, Herbert Poetzl wrote: > On Mon, Jan 17, 2011 at 06:24:15PM +0100, Tejun Heo wrote: > > On Mon, Jan 17, 2011 at 11:21:46AM -0600, James Bottomley wrote: > > > Expanders aren't SCSI devices either ... that means they don't > > > appear as visible to standard SCSI mechanisms like INQUIRY (SMP > > > isn't a SCSI protocol it's a SAS extension). They just appear as > > > part of the topology in the device tree. > > > Ah, okay. Then, things would be much simpler. I was worrying about > > how it would map to SCSI layer including INQUIRY emulations and all > > those stuff. Thanks for the info. > > So, any thoughts on how and where to add the PMP to the devices > available for sending SCSI or ATA commands to? > > I'm willing to try to add the required code, but I'm sure I'll > benefit from a few hints from the experts ... Well, I'm not sure I'd count as an expert on this piece: I haven't read the relevant ATA standards. From what I understand, SES packets are encapsulated over an ATA command for SEMB. In that case, it should be fairly simple to recognise this and present a SCSI device which simply encapsulates everything sent to it over this protocol. That would allow the ses ULD to attach seamlessly. James