From mboxrd@z Thu Jan 1 00:00:00 1970 From: Douglas Gilbert Subject: Re: [PATCH 1/4] sas: add flag for locally attached PHYs Date: Fri, 21 Oct 2005 13:25:46 +1000 Message-ID: <43585FBA.20506@torque.net> References: <91888D455306F94EBD4D168954A9457C048F0E34@nacos172.co.lsil.com> <4358497E.6070107@torque.net> <43584F8F.4070403@pobox.com> Reply-To: dougg@torque.net Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from zorg.st.net.au ([203.16.233.9]:16016 "EHLO borg.st.net.au") by vger.kernel.org with ESMTP id S964853AbVJUDYp (ORCPT ); Thu, 20 Oct 2005 23:24:45 -0400 In-Reply-To: <43584F8F.4070403@pobox.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Jeff Garzik Cc: "Moore, Eric Dean" , Luben Tuikov , Christoph Hellwig , jejb@steeleye.com, linux-scsi@vger.kernel.org Jeff Garzik wrote: > Douglas Gilbert wrote: > >> Just a suggestion if you want to bring /dev/sg into >> the picture for a SMP (and even a STP) passthrough. > > > Yep. That's another possibility, that falls into the 'block driver' > category [see list of categories in my 'ioctl' email], since it is > translated into a 'special' block request, and then sent to a normal > request_queue. > > Jens Axboe's bsg[1] has also been mentioned in the context of SMP. Jeff, Yes, I like the bsg model: one well known device (/dev/bsg), get a file descriptor and then bind to a "target". It reminded me of a network interface. As presented, it only bound to a block (or char?) device node (e.g. /dev/sda). I asked some questions about widening the variety of things it could bind to but Peter Jones suggested that binding was a necessary evil that should not be encouraged. So perhaps we could bind to a SAS host ... (and a SCSI device for those pesky things like safte, ses and wluns). Doug Gilbert