From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick Mansfield Subject: Re: [RFC] IBM Power RAID driver (ipr) Date: Thu, 22 Jan 2004 08:39:31 -0800 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20040122083931.A14612@beaverton.ibm.com> References: <40085EDA.4010802@us.ibm.com> <20040119183400.A4182@infradead.org> <400C3E70.9040702@us.ibm.com> <20040120133858.A15671@infradead.org> <400D5A28.1000301@us.ibm.com> <20040120180151.A18616@infradead.org> <400EE5E6.9080709@us.ibm.com> <20040122140248.C11283@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from e2.ny.us.ibm.com ([32.97.182.102]:13533 "EHLO e2.ny.us.ibm.com") by vger.kernel.org with ESMTP id S264575AbUAVQkS (ORCPT ); Thu, 22 Jan 2004 11:40:18 -0500 Content-Disposition: inline In-Reply-To: <20040122140248.C11283@infradead.org>; from hch@infradead.org on Thu, Jan 22, 2004 at 02:02:48PM +0000 List-Id: linux-scsi@vger.kernel.org To: Christoph Hellwig Cc: Brian King , linux-scsi@vger.kernel.org On Thu, Jan 22, 2004 at 02:02:48PM +0000, Christoph Hellwig wrote: > On Wed, Jan 21, 2004 at 02:49:42PM -0600, Brian King wrote: > > How about a flag in the scsi_device struct that an LLD could set in > > slave_configure, which would prevent upper layer drivers from binding > > to it? > > I'm not that happy about this. But the other solutions I could think > of are ven worse. > > > Then these devices could be found through the normal scsi scan > > and would have nice sysfs entries and sg devices for them. Not sure what > > we would call the flag... psuedo_device, fake_device? > > ghost? hidden? > > Could you cook up a patch? Why not just have the sd's show up? This is not much different then use of a volume manager. Finding the /dev/sg of the physical disk is the same problem as finding the sd. And then what about making them read only? I would rather any flag force sd to be read only rather than prevent upper level binding. Though having them show up as writable means the ipr can also be used to with the raw disks (not just for management of the physical disks). Also if we can tell via sysfs attributes that a bus (host:channel or maybe just a host) has physical disks attached, udev can be used to create entries in their own directory, like: /dev/physical/sdN Making the node read only can also be done with udev, but that does not help with root write access. -- Patrick Mansfield