From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753250AbXCRQuF (ORCPT ); Sun, 18 Mar 2007 12:50:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753252AbXCRQuF (ORCPT ); Sun, 18 Mar 2007 12:50:05 -0400 Received: from smtp.nokia.com ([131.228.20.173]:46069 "EHLO mgw-ext14.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753250AbXCRQuE convert rfc822-to-8bit (ORCPT ); Sun, 18 Mar 2007 12:50:04 -0400 Subject: Re: [PATCH 00/22 take 3] UBI: Unsorted Block Images From: Artem Bityutskiy Reply-To: dedekind@infradead.org To: Matt Mackall Cc: Linux Kernel Mailing List , Frank Haverkamp , Christoph Hellwig , David Woodhouse , Josh Boyer In-Reply-To: <20070318162720.GI10459@waste.org> References: <20070314151934.1112.70126.sendpatchset@localhost.localdomain> <20070318162720.GI10459@waste.org> Content-Type: text/plain; charset=utf-8 Date: Sun, 18 Mar 2007 18:49:39 +0200 Message-Id: <1174236579.17249.6.camel@sauron> Mime-Version: 1.0 X-Mailer: Evolution 2.8.3 (2.8.3-1.fc6) Content-Transfer-Encoding: 8BIT X-OriginalArrivalTime: 18 Mar 2007 16:49:39.0912 (UTC) FILETIME=[6B85FC80:01C7697D] X-eXpurgate-Category: 1/0 X-eXpurgate-ID: 149371::070318184941-21168BB0-4D105701/0-0/0-1 X-Nokia-AV: Clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2007-03-18 at 11:27 -0500, Matt Mackall wrote: > Forgive my ignorance, but why did you not implement the two features > above as device mapper layers instead? A device mapper can arbitrarily > transform I/O addresses and contents and has direct access to the > mapped device's ioctl interfaces, etc. Just because UBI is designed for flash devices, not block devices. Note, UBI is not for MMC/USB stick/SC/etc flashes, which are used as block devices, but for _bare_ flashes. Please, glance here to find more information about the different between flashes and block devices: http://www.linux-mtd.infradead.org/faq/general.html#L_mtd_vs_hdd -- Best regards, Artem Bityutskiy (Битюцкий Артём)