From owner-freebsd-current@FreeBSD.ORG Thu Sep 30 20:45:53 2010 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id F239B106564A; Thu, 30 Sep 2010 20:45:53 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 15B908FC21; Thu, 30 Sep 2010 20:45:52 +0000 (UTC) Received: from porto.topspin.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id XAA28970; Thu, 30 Sep 2010 23:45:51 +0300 (EEST) (envelope-from avg@icyb.net.ua) Received: from localhost.topspin.kiev.ua ([127.0.0.1]) by porto.topspin.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1P1Q0l-0008H7-Bf; Thu, 30 Sep 2010 23:45:51 +0300 Message-ID: <4CA4F6FF.5070402@icyb.net.ua> Date: Thu, 30 Sep 2010 23:45:51 +0300 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.9) Gecko/20100918 Lightning/1.0b2 Thunderbird/3.1.4 MIME-Version: 1.0 To: Alexander Motin References: <4CA3BD7C.9080306@feral.com> <4CA4CCE3.9060408@FreeBSD.org> In-Reply-To: <4CA4CCE3.9060408@FreeBSD.org> X-Enigmail-Version: 1.1.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: FreeBSD-Current Subject: Re: letting glabel recognise a media change X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 30 Sep 2010 20:45:54 -0000 on 30/09/2010 20:46 Alexander Motin said the following: > Andriy Gapon wrote: >> on 30/09/2010 01:28 Matthew Jacob said the following: >>> If something like that was in place, I assure you that things would start to use >>> it very quickly. >> >> I am not sure about this. >> Because, e.g. I don't see an easy way to know that media is changed in scsi_cd >> driver. That is, without polling. I don't consider polling to be an easy way for >> a number of reasons. > > SATA specification defines concept of Asynchronous Notification. It is > already used by port multipliers to report about PHY events. It is also > supposed to be used by CD drives to report media change. I haven't seen > such devices yet, but hope they may appear sometimes. Would this require some reverse-path from SIM driver to peripheral driver to deliver a notification? Do we have one? > And even without AN support it would be nice to implement proper > handling for SCSI "UA - media changed" errors within CAM. It still won't > be perfect without using polling, but probably still something. I agree. -- Andriy Gapon