From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luben Tuikov Subject: Re: [PATCH] make the SCSI mid-layer obey the device online flag Date: Fri, 06 Jun 2003 11:52:56 -0400 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <3EE0B8D8.4020909@rogers.com> References: <1054742495.1674.18.camel@mulgrave> <20030604165146.GA1426@beaverton.ibm.com> <1054754103.2360.8.camel@mulgrave> <20030606073603.A13259@infradead.org> <3EE0B316.4060207@rogers.com> <1054913984.1778.31.camel@mulgrave> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from fep03-mail.bloor.is.net.cable.rogers.com ([66.185.86.73]:33245 "EHLO fep03-mail.bloor.is.net.cable.rogers.com") by vger.kernel.org with ESMTP id S261801AbTFFPjX (ORCPT ); Fri, 6 Jun 2003 11:39:23 -0400 In-Reply-To: <1054913984.1778.31.camel@mulgrave> List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: Christoph Hellwig , Mike Anderson , SCSI Mailing List , Alan Stern James Bottomley wrote: > On Fri, 2003-06-06 at 11:28, Luben Tuikov wrote: > >>James was talking about ``device server not ready'' aliased to >>online -- i.e. if online is 0 then only INQUIRY or TUR should >>be sent from SCSI Core (unless SCSI Core decides to _know_ about >>the different ULP). The semantics on this are somewhat touched >>in the INQUIRY description in SPC-3. > > > Actually, not just TUR and INQUIRY. Think about errors on removable > media: we offline the device because of them and now the user needs to > unlock the door and eject the cartridge... > > Thus, we allow any special command because we assume it's part of error > handling (or post error clean up). So SCSI Core _has_ decided to know about ULP (block, tape, optical). Unless we (SCSI Core) generate those, it's a pickle to decide which are ``special'' enough commands. I think that we'll see more user space drivers controlling devices via sg sending commands to the device for exactly those kinds of problems... Else the burden on SCSI Core will/might be too great. -- Luben