From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Nicholas A. Bellinger" Subject: Re: [PATCH 0/8] tcm_loop updates Date: Tue, 23 Jun 2015 01:29:03 -0700 Message-ID: <1435048143.7460.50.camel@haakon3.risingtidesystems.com> References: <1434620622-65391-1-git-send-email-hare@suse.de> <20150619064855.GB1183@lst.de> <5583C117.4030103@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mail.linux-iscsi.org ([67.23.28.174]:57272 "EHLO linux-iscsi.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752500AbbFWI3F (ORCPT ); Tue, 23 Jun 2015 04:29:05 -0400 In-Reply-To: <5583C117.4030103@suse.de> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Hannes Reinecke Cc: Christoph Hellwig , Nic Bellinger , target-devel@vger.kernel.org, linux-scsi@vger.kernel.org, Ewan Milne On Fri, 2015-06-19 at 09:13 +0200, Hannes Reinecke wrote: > On 06/19/2015 08:48 AM, Christoph Hellwig wrote: > > What's the benefit of the SAS transport class writeout? I honestly > > always saw tcm_loop as a simple loopback driver, with the different > > transport IDs in the PR code as a gimmick. Note that vhost and > > xen-blkback copies that style and I did plan to consolidate it > > in common code. > > > The benefit is that tcm_loop will show up in the system as a 'real' > SAS hba; long-term goal is to simulate SAS multipathing here. > I was even planning on adding simlated FC infrastructure, too; > with that we could simulate FC multipathing, too, and our QA would > be _so_ happy... > Sounds like a reasonable use-case to support for loopback testing. > Again, these patches are mainly a collection of patches I've done to > test various scenarios, in the hope others might find them useful, > too. So I can easily hold off these patches until you've posted your > rework. > How different do you expect sas, fc, and iscsi transports to be..? Do you think this would this be better served by a simple tcm_loop LLD specific API for different multipath transports..?