From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261855AbTEFUtH (ORCPT ); Tue, 6 May 2003 16:49:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261876AbTEFUtH (ORCPT ); Tue, 6 May 2003 16:49:07 -0400 Received: from imladris.demon.co.uk ([193.237.130.41]:4228 "EHLO imladris.demon.co.uk") by vger.kernel.org with ESMTP id S261855AbTEFUtG (ORCPT ); Tue, 6 May 2003 16:49:06 -0400 Subject: Re: [PATCH] Only use MSDOS-Partitions by default on X86 From: David Woodhouse To: Jens Axboe Cc: Nicolas Pitre , Alan Cox , Russell King , =?ISO-8859-1?Q?J=F6rn?= Engel , Marcus Meissner , lkml In-Reply-To: <20030506184914.GL905@suse.de> References: <20030506183010.GK905@suse.de> <20030506184914.GL905@suse.de> Content-Type: text/plain Organization: Message-Id: <1052254888.7532.58.camel@imladris.demon.co.uk> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.2 (1.2.2-5.dwmw2) Date: Tue, 06 May 2003 22:01:28 +0100 Content-Transfer-Encoding: 7bit X-SA-Exim-Rcpt-To: axboe@suse.de, nico@cam.org, alan@lxorguk.ukuu.org.uk, rmk@arm.linux.org.uk, joern@wohnheim.fh-wedel.de, meissner@suse.de, linux-kernel@vger.kernel.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2003-05-06 at 19:49, Jens Axboe wrote: > I see, that would indeed be a bigger job :). Just the block layer would > not be hard, especially if you make the restriction that the block > drivers usable would be ones that used a make_request strategy for > handling requests. That would allow you to kill ll_rw_blk.c, > deadline-iosched.c, and elevator.c. That's some 21k of text and 2k of > data on this box. That's a little short of what I was intending. Ideally we stick 'struct request', 'struct buffer_head' and 'struct bio' inside #ifdef CONFIG_BLK_DEV, then kill all the dead code which uses them. block_dev.c becomes... int blkdev_open(struct inode * inode, struct file * filp) { return -ENXIO; } Don't look at JFFS; that still needs to be able to open a block device even though it never actually _uses_ it. Look at the non-blkdev mount path for JFFS2 instead. The _only_ thing we use the mtdblock device for is to look at its minor number and use it to pick the right MTD device -- it used to give us the locking on simultaneous mounts for free, a constant device number for NFS exporting, and a cheap way to work around the bug that the 'root=' command line option isn't available to filesystems directly. mtdblock.c cleanup noted with interest -- I'll play with that shortly; thanks. Note that you don't actually need flash hardware, you can load the 'mtdram' device which fakes it with vmalloc-backed storage instead. Not too useful for powerfail-testing but for mounting something like ext2 on mtdblock on mtdram it's fine. -- dwmw2