From: Andrew Morton Subject: Re: [Ext2-devel] [PATCH 1/5] Forking ext4 filesystem from ext3 filesystem Date: Thu, 10 Aug 2006 15:18:13 -0700 Message-ID: <20060810151813.ae352cd8.akpm@osdl.org> References: <1155172622.3161.73.camel@localhost.localdomain> <20060809233914.35ab8792.akpm@osdl.org> <44DB8036.5020706@us.ibm.com> <44DB936D.2080909@garzik.org> <20060810132720.4d9fced4.akpm@osdl.org> <44DB9E6C.9070808@garzik.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Jeff Garzik , linux-fsdevel@vger.kernel.org, cmm@us.ibm.com, ext2-devel@lists.sourceforge.net, Badari Pulavarty , linux-kernel@vger.kernel.org Return-path: Received: from smtp.osdl.org ([65.172.181.4]:59351 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1751218AbWHJWVL (ORCPT ); Thu, 10 Aug 2006 18:21:11 -0400 To: Alex Tomas In-Reply-To: Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Fri, 11 Aug 2006 01:11:23 +0400 Alex Tomas wrote: > >> A buffer_head is the kernel's sole abstraction of a disk block. > >> Filesystems use disk blocks a lot, and they need such an abstraction. > > JG> IMO Al Viro work has shown that you can do pagecache I/O without needing > JG> such a heavyweight system. > > in delayed allocation patch for ext3 (ontop of extents) we do use > bio's for data. As does ext3 with `-o writeback,nobh'.