From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933063Ab2EOSK1 (ORCPT ); Tue, 15 May 2012 14:10:27 -0400 Received: from a.ns.miles-group.at ([95.130.255.143]:47834 "EHLO radon.swed.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932750Ab2EOSKX (ORCPT ); Tue, 15 May 2012 14:10:23 -0400 Message-ID: <4FB29BF9.7050200@nod.at> Date: Tue, 15 May 2012 20:10:01 +0200 From: Richard Weinberger User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120421 Thunderbird/12.0 MIME-Version: 1.0 To: Subodh Nijsure CC: linux-mtd@lists.infradead.org, Heinz.Egger@linutronix.de, tglx@linutronix.de, tim.bird@am.sony.com, linux-kernel@vger.kernel.org, dedekind1@gmail.com Subject: Re: [RFC v4] UBI: Fastmap support (aka checkpointing) References: <1337101871-31181-1-git-send-email-richard@nod.at> <4FB296EA.5090104@grid-net.com> In-Reply-To: <4FB296EA.5090104@grid-net.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Subodh, Am 15.05.2012 19:48, schrieb Subodh Nijsure: > Hello Richard, > > On 05/15/2012 10:11 AM, Richard Weinberger wrote: >> v1: https://lwn.net/Articles/481612/ >> v2: https://lwn.net/Articles/496586/ >> v3: Didn't release it to linux-mtd > Will kernel that has older UBI drivers be able to mount and update the > UBI volumes that have been created with checkpointing feature? Of course! > Say I have bootrom that has 3.0.X kernel that has no knowledge of UBI > checkpointing, and my flash /dev/mtd2 has UBI volume with checkpointing > enabled. Will this bootrom be able to attach /dev/mtd2 and mount UBI > volume and read/write files on it? Sure! Your bootrom will scan the UBI volume and detect two unknown internal volumes with compat=delete in their volume headers. So, it will delete the two fastmap volumes and continue scanning. It can alter the volume and so on. Thanks, //richard From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from a.ns.miles-group.at ([95.130.255.143] helo=radon.swed.at) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1SUMCV-0006wG-88 for linux-mtd@lists.infradead.org; Tue, 15 May 2012 18:10:24 +0000 Message-ID: <4FB29BF9.7050200@nod.at> Date: Tue, 15 May 2012 20:10:01 +0200 From: Richard Weinberger MIME-Version: 1.0 To: Subodh Nijsure Subject: Re: [RFC v4] UBI: Fastmap support (aka checkpointing) References: <1337101871-31181-1-git-send-email-richard@nod.at> <4FB296EA.5090104@grid-net.com> In-Reply-To: <4FB296EA.5090104@grid-net.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: dedekind1@gmail.com, linux-kernel@vger.kernel.org, Heinz.Egger@linutronix.de, linux-mtd@lists.infradead.org, tim.bird@am.sony.com, tglx@linutronix.de List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Subodh, Am 15.05.2012 19:48, schrieb Subodh Nijsure: > Hello Richard, > > On 05/15/2012 10:11 AM, Richard Weinberger wrote: >> v1: https://lwn.net/Articles/481612/ >> v2: https://lwn.net/Articles/496586/ >> v3: Didn't release it to linux-mtd > Will kernel that has older UBI drivers be able to mount and update the > UBI volumes that have been created with checkpointing feature? Of course! > Say I have bootrom that has 3.0.X kernel that has no knowledge of UBI > checkpointing, and my flash /dev/mtd2 has UBI volume with checkpointing > enabled. Will this bootrom be able to attach /dev/mtd2 and mount UBI > volume and read/write files on it? Sure! Your bootrom will scan the UBI volume and detect two unknown internal volumes with compat=delete in their volume headers. So, it will delete the two fastmap volumes and continue scanning. It can alter the volume and so on. Thanks, //richard