Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261391AbVAGMkD (ORCPT ); Fri, 7 Jan 2005 07:40:03 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261393AbVAGMkD (ORCPT ); Fri, 7 Jan 2005 07:40:03 -0500 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:7685 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S261391AbVAGMjx (ORCPT ); Fri, 7 Jan 2005 07:39:53 -0500 Date: Fri, 7 Jan 2005 12:39:47 +0000 From: Russell King To: Pierre Ossman , Al Viro , Jens Axboe Cc: LKML Subject: Re: [PATCH] MMC block removable flag Message-ID: <20050107123947.B23665@flint.arm.linux.org.uk> Mail-Followup-To: Pierre Ossman , Al Viro , Jens Axboe , LKML References: <41D3646F.5050408@drzeus.cx> <20041230095448.A9500@flint.arm.linux.org.uk> <41D4253D.8070006@drzeus.cx> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <41D4253D.8070006@drzeus.cx>; from drzeus-list@drzeus.cx on Thu, Dec 30, 2004 at 04:56:45PM +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2078 Lines: 41 On Thu, Dec 30, 2004 at 04:56:45PM +0100, Pierre Ossman wrote: > Russell King wrote: > >On Thu, Dec 30, 2004 at 03:14:07AM +0100, Pierre Ossman wrote: > >>A MMC card is a highly removable device. This patch makes the block > >>layer part of the MMC layer set the removable flag. > > > >I have this patch also floating around, but I've decided it isn't needed. > >I believe this flag is to indicate that we have removable media for a > >block device rather than to indicate that the block device can be removed. > > > >However, when we insert and remove a MMC card, we create and destroy the > >block device itself. Therefore, as far as the block layer is concerned, > >the device itself is being inserted and removed, so telling the block > >layer that the media is removable is just silly - you can't separate the > >flash media from the on-board MMC controller. > > > >(Note: any block device can be removed - you just rmmod the module > >supplying the block device driver, but this doesn't mean we mark all > >block devices with GENHD_FL_REMOVABLE.) > > I suspect that the removable flag might be used in different GUI:s to > figure out with block devices should be presented to the user in a nice > way. It's usually just the removable devices that need some form of > special handling. So even though, as you point out, the entire device > disappears it might be useful from a user interface perspective to have > this hint set. From what I've found this flag doesn't seem to change any > handling inside the kernel, just how the device should be perceived. Can anyone comment on the purpose of this (GENHD_FL_REMOVABLE) flag? Al? Jens? -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 PCMCIA - http://pcmcia.arm.linux.org.uk/ 2.6 Serial core - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/