Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265080AbTFRTjJ (ORCPT ); Wed, 18 Jun 2003 15:39:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265234AbTFRTjJ (ORCPT ); Wed, 18 Jun 2003 15:39:09 -0400 Received: from fmr03.intel.com ([143.183.121.5]:18938 "EHLO hermes.sc.intel.com") by vger.kernel.org with ESMTP id S265080AbTFRTjG convert rfc822-to-8bit (ORCPT ); Wed, 18 Jun 2003 15:39:06 -0400 Message-ID: From: "Perez-Gonzalez, Inaky" To: "'viro@parcelfarce.linux.theplanet.co.uk'" , "Perez-Gonzalez, Inaky" Cc: "'Kevin P. Fleming'" , "'Alan Stern'" , "'Patrick Mochel'" , "'Russell King'" , "'Greg KH'" , "'linux-kernel@vger.kernel.org'" Subject: RE: Flaw in the driver-model implementation of attributes Date: Wed, 18 Jun 2003 12:52:57 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1819 Lines: 45 > From: viro@parcelfarce.linux.theplanet.co.uk [mailto:viro@parcelfarce.linux.theplanet.co.uk] > > > So what? _every_ block device will have some form of physical > > back-up that can be linked back into sysfs. > > ... except ones that will not. Wonderful. I bow to that logics - there > is nothing it wouldn't cover. Thank you }:) - we like it or not, data goes somewhere. > > In the tree structure it makes sense, because each block > > device, at the end is or a partition (and thus is embedded > > in a "true" block device) or a true block device on a 1:1 > > relationship with a physical device. > > BS. There is nothing to stop you from having a block device that talks > to userland process instead of any form of hardware. As the matter of > fact, we already have such a beast - nbd. There is also RAID - where Sure, there: /sys/devices/"virtual"/nbd/0 > there fsck is 1:1 here? There's also such thing as RAID5 over partitions > that sit on several disks - where do you see 1:1 or 1:n or n:1? /sys/devices/"virtual"/raid/0 > There is such thing as e.g. encrypted loop over NFS. There are all > sorts of interesting things, with all sorts of interesting relationship > to some pieces of hardware. /sys/devices/"virtual"/loopback/0 Don't you have to do "-o loop" when you mount a loopback? ... same thing happens with nbd and RAID, you have to tell the kernel to create the actual devices (or it does); that they show up nowhere in sysfs (yet) is different. I?aky P?rez-Gonz?lez -- Not speaking for Intel -- all opinions are my own (and my fault) - 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/