Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161795AbbKTBBn (ORCPT ); Thu, 19 Nov 2015 20:01:43 -0500 Received: from ipmail06.adl2.internode.on.net ([150.101.137.129]:44476 "EHLO ipmail06.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161118AbbKTBBm (ORCPT ); Thu, 19 Nov 2015 20:01:42 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: A2DPCQBtcE5WPALtLHleKAECgxBTb6t0AQEBAQEBBos5hSyEDR2FbAICAQECgU9NAQEBAQEBBwEBAQFAAT+ENQEBBDocIxAIAxgJJQ8FJQMHGhOILQ7AMgEBAQEBBQIBHAQZhXSFRYJxhkgFlkyFI4gDgWOEQJYsgnQdgWoqNIUtAQEB Date: Fri, 20 Nov 2015 11:58:43 +1100 From: Dave Chinner To: Richard Weinberger Cc: Octavian Purdila , xfs , linux-fsdevel , LKML Subject: Re: [RFC PATCH] xfs: support for non-mmu architectures Message-ID: <20151120005843.GP14311@dastard> References: <1447800381-20167-1-git-send-email-octavian.purdila@intel.com> <20151119232455.GM14311@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1745 Lines: 42 On Fri, Nov 20, 2015 at 12:54:02AM +0100, Richard Weinberger wrote: > On Fri, Nov 20, 2015 at 12:24 AM, Dave Chinner wrote: > > On Wed, Nov 18, 2015 at 12:46:21AM +0200, Octavian Purdila wrote: > >> Naive implementation for non-mmu architectures: allocate physically > >> contiguous xfs buffers with alloc_pages. Terribly inefficient with > >> memory and fragmentation on high I/O loads but it may be good enough > >> for basic usage (which most non-mmu architectures will need). > > > > Can you please explain why you want to use XFS on low end, basic > > non-MMU devices? XFS is a high performance, enterprise/HPC level > > filesystem - it's not a filesystem designed for small IoT level > > devices - so I'm struggling to see why we'd want to expend any > > effort to make XFS work on such devices.... > > The use case is the Linux Kernel Library: > https://lkml.org/lkml/2015/11/3/706 > > Using LKL and fuse you can mount any kernel filesystem using fuse > as non-root. IOWs, because we said no to unprivileged mounts, instead the proposal is to linking all the kernel code into userspace so you can do unprivielged mounts that way? IOWs, you get to say "it secure because it's in userspace" and leave us filesystem people with all the shit that comes with allowing users to mount random untrusted filesystem images using code that was never designed to allow that to happen? Fmeh. Not a convincing argument by far. Cheers, Dave. -- Dave Chinner david@fromorbit.com -- 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/