From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Byan Subject: Re: remove-single-device removes mounted HDDs (kernel 2.6) Date: Wed, 7 Sep 2005 13:48:57 -0400 Message-ID: <5b5253d4000c9c780b80964e344bd382@egenera.com> References: <20050906212801.GB14057@cs.umn.edu> <20050907104932.GA14200@lst.de> <20050907124504.GA13614@cs.umn.edu> <20050907215816C.fujita.tomonori@lab.ntt.co.jp> <431F20AA.1090101@cs.wisc.edu> Mime-Version: 1.0 (Apple Message framework v622) Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from roadrunner-base.egenera.com ([63.160.166.46]:11667 "EHLO roadrunner-base.egenera.com") by vger.kernel.org with ESMTP id S1751257AbVIGRtA (ORCPT ); Wed, 7 Sep 2005 13:49:00 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by roadrunner.egenera.com (Postfix) with ESMTP id BA112A0510 for ; Wed, 7 Sep 2005 13:48:59 -0400 (EDT) Received: from roadrunner-base.egenera.com ([127.0.0.1]) by localhost (coyote.egenera.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 07198-07 for ; Wed, 7 Sep 2005 13:48:58 -0400 (EDT) Received: from [172.23.2.91] (southeast.egenera.com [63.160.166.4]) by roadrunner.egenera.com (Postfix) with ESMTP id 10A4CA050E for ; Wed, 7 Sep 2005 13:48:58 -0400 (EDT) In-Reply-To: <431F20AA.1090101@cs.wisc.edu> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org On Sep 6, 2005, at 11:43 AM, Christoph Hellwig wrote: > On Thu, Aug 11, 2005 at 06:50:03PM +0200, Harald Seipp wrote: >> Christoph Hellwig wrote on 11.08.2005 18:40:03: >>> On Thu, Aug 11, 2005 at 05:44:46PM +0200, Harald Seipp wrote: >>>> Thank you for your quick responses! It finally looks like the task >>>> I need >>>> to do - fully rescan all hosts for newly attached/changed devices - >>>> must >>>> include the logic to skip devices with mounted fs for 2.6. >>> >>> Why do you want to rescan a full bus anyway? What SCSI transport do >>> you >>> want this for? All transports where new targets can be hot-plugged >>> should >>> be doing automatic scanning already. >> Old-fashioned parallel SCSI bus and FC/SAN where there are no hot-plug >> events AFAIK. > > In FC you get per-target events, although none for new LUs showing up > on a given target (in fact no SAM transport does the latter) I believe some Fibre Channel storage arrays generate RSCN's when new logical units are created (although I don't know if the existing Linux Fibre Channel HBA drivers propagate these registered state change notifications to the hot-plug subsystem). I understand that many iSCSI storage arrays will generate a SCSI Asynchronous Event Notification for the REPORTED LUNS DATA HAS CHANGED Unit Attention condition that SPC-3 says shall be generated when a target changes its logical unit inventory, provided that AEN's are enabled in the control mode page. So there are SAM transports that generate events when a new LU shows up. I'm curious as to what plans, if any, exist for handling these events in Linux. Regards, -Steve -------- Steve Byan Software Architect Egenera, Inc. 165 Forest Street Marlboro, MA 01752 (508) 858-3125