From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian King Subject: Re: [PATCH] Hidden scsi devices Date: Thu, 22 Jan 2004 11:07:22 -0600 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <4010034A.3040903@us.ibm.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from e4.ny.us.ibm.com ([32.97.182.104]:10148 "EHLO e4.ny.us.ibm.com") by vger.kernel.org with ESMTP id S266274AbUAVRH0 (ORCPT ); Thu, 22 Jan 2004 12:07:26 -0500 Received: from northrelay02.pok.ibm.com (northrelay02.pok.ibm.com [9.56.224.150]) by e4.ny.us.ibm.com (8.12.10/8.12.2) with ESMTP id i0MH7PvM309350 for ; Thu, 22 Jan 2004 12:07:25 -0500 List-Id: linux-scsi@vger.kernel.org To: Martin Peschke3 Cc: linux-scsi@vger.kernel.org Martin Peschke3 wrote: > Brian, > > why should a LLDD need to bother about device characteristics? > I tend to say that it is completely up to upper layer drivers to > handle such device specialties. > How does a LLDD know about that r/w protection feature anyway? Because the device is reported to the LLDD by the adapter as a specific device type. The adapter creates a configuration table describing all attached devices that the LLDD must retrieve. In this configuration table there are several types of devices: 1. Adapter itself. 2. Generic SCSI devices. 3. Logical disk array devices (VSET) 4. Advanced function devices (devices in RAID arrays). In my situation the only one who knows about this device characteristic is the LLDD. -- Brian King eServer Storage I/O IBM Linux Technology Center