Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262654AbUJ1Aej (ORCPT ); Wed, 27 Oct 2004 20:34:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262606AbUJ1AcQ (ORCPT ); Wed, 27 Oct 2004 20:32:16 -0400 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:63213 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id S262687AbUJ1Abb (ORCPT ); Wed, 27 Oct 2004 20:31:31 -0400 Date: Thu, 28 Oct 2004 01:31:29 +0100 From: Al Viro To: Lei Yang Cc: linux-kernel@vger.kernel.org Subject: Re: loopback on block device Message-ID: <20041028003129.GL24336@parcelfarce.linux.theplanet.co.uk> References: <417FE703.3070608@ece.northwestern.edu> <417FE922.7080009@ece.northwestern.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <417FE922.7080009@ece.northwestern.edu> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 868 Lines: 17 On Wed, Oct 27, 2004 at 01:29:54PM -0500, Lei Yang wrote: > >Here is a question for loopback device. As far as I understand, the > >loopback device is used to mount files as if they were block devices. > > > >Then Why I could do "losetup -e XOR /dev/loop0 /dev/ram0" ? Notice > >that ram0 is not mounted anywhere and does not have a filesystem on > >it. I've tried that command and there seems to be no error. I got > >confused and looked into loop.c, it seems to me that a loopback device > >should be associated with a "backing file", why would it work on a > >block device anyway? Because block device is a file. - 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/