From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Christie Subject: Re: [PATCH RFC 2/2] implement transport scan callout for iscsi Date: Tue, 24 May 2005 14:01:04 -0700 Message-ID: <42939610.3070104@cs.wisc.edu> References: <42936441.0b798bab.39a4.ffff9774SMTPIN_ADDED@mx.googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from sabe.cs.wisc.edu ([128.105.6.20]:49799 "EHLO sabe.cs.wisc.edu") by vger.kernel.org with ESMTP id S262072AbVEXVBM (ORCPT ); Tue, 24 May 2005 17:01:12 -0400 In-Reply-To: <42936441.0b798bab.39a4.ffff9774SMTPIN_ADDED@mx.googlegroups.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: open-iscsi@googlegroups.com Cc: 'SCSI Mailing List' Alex Aizman wrote: > James Bottomley wrote: > >>On Sat, 2005-05-21 at 14:39 -0700, Mike Christie wrote: >> >>>`-- session1 >>> |-- connection1:0 >>> `-- target1:0:0 >>> |-- 1:0:0:0 >> >>I understand that session1 represents the physical connection >>between the target and the initiator, but what's connection1:0? > > > It's a leading transport connection of the session1 (above). Quoting the > spec (http://www.faqs.org/rfcs/rfc3720.html): > > - According to [SAM2], the I_T nexus is a relationship > between a SCSI Initiator Port and a SCSI Target Port. For iSCSI, > this relationship is a session, defined as a relationship between > an iSCSI Initiator's end of the session (SCSI Initiator Port) and > the iSCSI Target's Portal Group. > > The session itself is not a "physical connection"; it aggregates one or more > transport connections between a given SCSI Initiator Port and a SCSI Target > Port. There is always at least one (leading) connection. > So just to be clear, open-iscsi can support multiple connections per session. Do you want us to completely remove this feature for mainline? I know you and christoph have given me this answer many times before, but not seeing a reply to Nicholas's question about just disabling may have created some doubt as to the extent people have to go? Since open-iscsi pushed the connection management code to userspace, removing MCS from the driver will not be too terrible a job for us though. The connection dir for single connection sessions though is just a nice way to export the kernel structure's info and have it also reflect the iSCSI RFC's definitions at the same time. For sfnet we used to throw everything in one dir becuase it did not have a connection structure so it simplified refcounting.