From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 9 Apr 2018 02:25:22 -0700 From: Christoph Hellwig To: Douglas Gilbert Cc: Christoph Hellwig , Hannes Reinecke , Tim Walker , linux-scsi , linux-block@vger.kernel.org Subject: Re: Multi-Actuator SAS HDD First Look Message-ID: <20180409092522.GA9394@infradead.org> References: <20180326170840.0130f366@pentland.suse.de> <1c800f70-0d50-bc5b-3b73-e36a1cea0eec@interlog.com> <20180403074637.GB13259@infradead.org> <20180406082418.127a0ec6@pentland.suse.de> <20180406064236.GA17456@infradead.org> <361c204d-f9be-978a-5778-81ecaeb143e0@interlog.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <361c204d-f9be-978a-5778-81ecaeb143e0@interlog.com> Sender: linux-scsi-owner@vger.kernel.org List-ID: On Fri, Apr 06, 2018 at 01:09:08PM -0400, Douglas Gilbert wrote: > So you found a document that outlines NVMe's architecture! Could you > share the url (no marketing BS, please)? You can always take a look at the actual spec: http://nvmexpress.org/wp-content/uploads/NVM-Express-1_3a-20171024_ratified.pdf But in summary: while in SCSI your Nexus for any command is with the logic unit, in NVMe it is with the controller. Many admin commands operate on the whole controller. > And a serious question ... How would you map NVMe's (in Linux) > subsystem number, controller device minor number, CNTLID field > (Identify ctl response) and namespace id onto the SCSI subsystem's > h:c:t:l ? I wouldn't because the scheme already doesn't make any sense for SCSI, nevermind should we try to map NVMe into a scsi specific worldview. > > Doug Gilbert > ---end quoted text---