From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladislav Bolkhovitin Subject: Re: SCSI TMF processing; tag allocation Date: Tue, 16 Nov 2010 23:28:53 +0300 Message-ID: <4CE2E985.4050102@vlnb.net> References: <380694.87733.qm@web31812.mail.mud.yahoo.com> <20101113123750.GF18258@parisc-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20101113123750.GF18258@parisc-linux.org> Sender: linux-kernel-owner@vger.kernel.org To: Matthew Wilcox Cc: Luben Tuikov , Greg KH , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, tj@kernel.org, James Bottomley , Jens Axboe List-Id: linux-scsi@vger.kernel.org Matthew Wilcox, on 11/13/2010 03:37 PM wrote: > SPC-4 seems to indicate (in the INQUIRY command, 6.4.2) that support > for queueing is now non-optional, and even support for basic queueing > has been removed, replaced only with the 'command management model'. > I must confess to being somewhat confused by the difference between the > 'basic queue' model and 'command management' model The 'command management model' is what was called 'full task management model' in SAM-3. The difference of it with 'basic task management model' in SAM-3 is that (basically) in the latter: - Support only for SIMPLE or ORDERED commands (not both) - For SIMPLE commands their reorder can't be controlled - On any error all queued commands must be aborted and this behavior can't be controlled. Vlad