From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [ANN] Squashfs 3.3 released Date: Wed, 21 Nov 2007 14:48:35 +0000 Message-ID: <20071121144835.GA7556@infradead.org> References: <472EFACA.1090308@lougher.demon.co.uk> <20071105115624.GJ14432@baikonur.stro.at> <4731E880.6010303@lougher.demon.co.uk> <20071120235048.GA15764@redhat.com> <47443A83.2020607@lougher.demon.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Dave Jones , maximilian attems , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org To: Phillip Lougher Return-path: Received: from pentafluge.infradead.org ([213.146.154.40]:49425 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753764AbXKUOsu (ORCPT ); Wed, 21 Nov 2007 09:48:50 -0500 Content-Disposition: inline In-Reply-To: <47443A83.2020607@lougher.demon.co.uk> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Wed, Nov 21, 2007 at 02:02:43PM +0000, Phillip Lougher wrote: > Unfortunately the move to fixed little endian filesystem will involve > another filesystem layout change. The current filesystem layout still > uses packed bitfield structures, and it is impossible to swap these > using the standard kernel swap macros. Removal of my routines that can > properly swap packed bitfield structures is another change demanded by > the Linux kernel mailing list. The normal way to do it is to use shift and mask after doing the endian conversion. But the problem with bitfields is that they can have different kinds of layouts depending on the compiler or abi which is another reason to avoid them in ondisk/wire formats.