From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Bellinger Subject: Re: [PATCH] /proc/scsi/map Date: 22 Jun 2002 12:18:19 -0600 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <1024769900.6875.139.camel@subjeKt> References: <3D14B2CF.90002@pacbell.net> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <3D14B2CF.90002@pacbell.net> List-Id: linux-scsi@vger.kernel.org To: David Brownell Cc: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org On Sat, 2002-06-22 at 11:24, David Brownell wrote: > > On the other hand there is the obvious fact that an iSCSI initiator > > driver is not attached to a bus, and assuming /root/iSCSI.target/disk1 > > etc, is out of the question. There is a real need for a solution to > > handle virtual devices (as stated your previous message) that are not > > assoicated with any physical connectors. > > There are those who see the IP stack as a kind of logical bus ... :) > It's just not tied any specific hardware interface; it's "multipathed" in > some sense. Linking it to an eth0 entry in $DRIVERFS/root/pci0/00:10.0 > would be wrong, since it can also be accessed through eth2. > > Why shouldn't there be a $DRIVERFS/net/ipv4@10.42.135.99/... style hookup > for iSCSI devices? Using whatever physical addressing the kernel uses > there, which I assume wouldn't necessarily be restricted to ipv4. (And > not exposing physical network topology -- routing! -- in driverfs.) > > Giving the IP stack its own directory (leaf?) under driverfs root sounds interesting enough and could have some potential uses, but in the case of iSCSI there are a few problems: iSCSI Names (aka: iSCSI Qualified Names or IEEE EUI-64 names ) are world wide unique and are intended to stay with the iSCSI Node throughout its lifetime, regardless of IP/HBA/NIC/etc changes. Also an iSCSI session can include multiple TCP connections with each different IP addresses, so the format of $DRIVERFS/net/ipv4@iSCSI.target.ip is insufficent. This reiterates the need for a sound logical device naming scheme that fits into driverfs without mucking up the basic structure. Not being a expert on naming, the least offensive format I can think with regard to iSCSI would be something along the lines of: $DRIVERFS/virt/iscsi/iqn.2002-06.com.foo.super.turbo.disk.array.3543/disk0 being the iqn for an iSCSI Target node as viewed by an iSCSI Initiator node. Nicholas Bellinger