From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751138AbVIUQbF (ORCPT ); Wed, 21 Sep 2005 12:31:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751133AbVIUQbE (ORCPT ); Wed, 21 Sep 2005 12:31:04 -0400 Received: from [81.2.110.250] ([81.2.110.250]:10150 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S1751130AbVIUQbD (ORCPT ); Wed, 21 Sep 2005 12:31:03 -0400 Subject: Re: [RFC/BUG?] ide_cs's removable status From: Alan Cox To: Richard Purdie Cc: LKML , Dominik Brodowski , bzolnier@gmail.com, linux-ide@vger.kernel.org In-Reply-To: <1127319328.8542.57.camel@localhost.localdomain> References: <1127319328.8542.57.camel@localhost.localdomain> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Wed, 21 Sep 2005 17:57:08 +0100 Message-Id: <1127321829.18840.18.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mer, 2005-09-21 at 17:15 +0100, Richard Purdie wrote: > As ide_cs only creates the block devices when a card is present, I think > it shouldn't be set as removable. As a point of reference, the MMC > system does not set the removable flag for exactly this reason (There is > an email from Russell King explaining this - > http://lkml.org/lkml/2005/1/8/165). I can't comment on the MMC layer or its core requirements as I don't know them well. IDE PCMCIA does however encompass removal devices. The removable flag is set so that we get removable media behaviour - that is the media can change under us and we must not cache partition data. The current behavioiur in that sense is correct. > > It is worth noting the MMC subsystem works with my evil udev script. If > I apply the patch below (which removes the removable flag for flash > devices), I don't see this loop. But does MMC have a media change detect, and if not does the right thing occur if you swap cards with partition tables ? > 1. Can anyone provide details on what the bits in id->config really > mean? ATA standards are all available for download. > 2. Which other drivers exploit the "if (id->config & (1<<7)) > drive->removable = 1;" code? Is it just ide_cs? It might be currently because the old IDE layer has no hotplug support (not even for PCMCIA - it happens to work some days) but that wasn't true in 2.4-ac or some 2.6-ac. It sounds like something needs to be smarter about whether the media has changed - could be kernel but it seems like a user space problem. I note that the standard Gnome tools "just work" in this case so perhaps you can see how they do it. Alan