From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dell-paw-3.cambridge.redhat.com ([195.224.55.237] helo=passion.cambridge.redhat.com) by pentafluge.infradead.org with esmtp (Exim 3.22 #1 (Red Hat Linux)) id 159lF1-0000gN-00 for ; Tue, 12 Jun 2001 11:17:43 +0100 From: David Woodhouse In-Reply-To: <3B25EBA0.71C2EF64@iriti.cnr.it> References: <3B25EBA0.71C2EF64@iriti.cnr.it> To: Fabrizio Pollastri Cc: linux-mtd@lists.infradead.org Subject: Re: "add only" fs Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 12 Jun 2001 11:23:02 +0100 Message-ID: <18752.992341382@redhat.com> Sender: linux-mtd-admin@lists.infradead.org Errors-To: linux-mtd-admin@lists.infradead.org List-Help: List-Post: List-Subscribe: , List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: pollastri@iriti.cnr.it said: > a common problem in embedded systems is to log important data in a way > safe against power failure and software bugs. The question is: may be > jffs2 the right place to introduce an "add only" protection? It can be > at partition level, in such a way that mounting that partition as "add > only" I am protected against loss of data, because I can only create > new files and/or append data to existing files and never delete or > truncate a file unless the partition is remounted rw. JFFS2 _has_ to move data around, even data which haven't changed. If you want 100% guarantees (or as close as possible) that some parts can't change, put them in a separate partition which you mount readonly. -- dwmw2