From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH 0/11] Per-bdi writeback flusher threads v9 Date: Fri, 29 May 2009 00:27:18 +0200 Message-ID: <20090528222718.GE11363@kernel.dk> References: <1243511204-2328-1-git-send-email-jens.axboe@oracle.com> <4A1E9D0B.4090402@gmail.com> <4A1E9D8B.8020908@gmail.com> <1243542908.6645.104.camel@laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Artem Bityutskiy , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, tytso@mit.edu, chris.mason@oracle.com, david@fromorbit.com, hch@infradead.org, akpm@linux-foundation.org, jack@suse.cz, yanmin_zhang@linux.intel.com, richard@rsk.demon.co.uk, damien.wyart@free.fr To: Peter Zijlstra Return-path: Received: from brick.kernel.dk ([93.163.65.50]:37122 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751109AbZE1W1R (ORCPT ); Thu, 28 May 2009 18:27:17 -0400 Content-Disposition: inline In-Reply-To: <1243542908.6645.104.camel@laptop> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Thu, May 28 2009, Peter Zijlstra wrote: > On Thu, 2009-05-28 at 17:19 +0300, Artem Bityutskiy wrote: > > Artem Bityutskiy wrote: > > > question is - should it? 'bdi_register()' a block device, > > > but we do not have one. > > > > Sorry, wanted to say: 'bdi_register()' registers a block > > device. > > BDI stands for backing device info and is not related to block devices > other than that block devices can also be (ok, always are) backing > devices. > > If you want to do writeback, you need a backing device to write to. The > BDI is the device abstraction for writeback. Precisely. Apparently ubifs doesn't register its backing device. I fixed a similar issue in btrfs, I'll do an audit of the file systems and fix that up. -- Jens Axboe