From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J.E.J. Bottomley" Subject: Re: [PATCH] get rid of ->detect for upper layer drivers Date: Thu, 07 Nov 2002 10:50:08 -0500 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <200211071550.gA7Fo9p03079@localhost.localdomain> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: (from root@localhost) by pogo.mtv1.steeleye.com (8.9.3/8.9.3) id HAA24964 for ; Thu, 7 Nov 2002 07:50:13 -0800 In-Reply-To: Message from Christoph Hellwig of "Thu, 07 Nov 2002 16:39:54 +0100." <20021107163954.B9189@lst.de> List-Id: linux-scsi@vger.kernel.org To: Christoph Hellwig Cc: Mike Anderson , "Adam J. Richter" , linux-scsi@vger.kernel.org hch@lst.de said: > Yupp, IMHO we should move to a better interpretation of the driver > model. But the question how do we solve the sg issue. There are two > ways I could imagine: There are other nasties waiting in the pipeline. The one that's been bothering me is the SCSI3 Controller Commands (for arrays and the like). This basically adds array controller information to a standard direct-access device, but crucially, it has two different (and incompatible with direct-access) ways of addressing the array: physical-by real disk and logical-by the actual RAID-n unit. Most of the time a SCC device is an sd device but with a translation in the addressing mode. It makes sense that SCC would somehow filter the sd attachment and add a special scc device type just for the controlling node. By the way, we already have this in the tree: the compaq cpqfc driver does on the fly translation for SCC devices into SD at the low level (that's for the RA4100 array). James