From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752641Ab0G0R1c (ORCPT ); Tue, 27 Jul 2010 13:27:32 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:35789 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752287Ab0G0R1b (ORCPT ); Tue, 27 Jul 2010 13:27:31 -0400 Date: Tue, 27 Jul 2010 13:27:31 -0400 From: Christoph Hellwig To: Jan Kara Cc: Christoph Hellwig , LKML , Andrew Morton Subject: Re: [PATCH 1/3] bdi: Use parent filesystem BDI for inodes not capable of writeback Message-ID: <20100727172731.GA25727@infradead.org> References: <1280250301-17603-1-git-send-email-jack@suse.cz> <1280250301-17603-2-git-send-email-jack@suse.cz> <20100727170903.GA9034@infradead.org> <20100727172437.GE6820@quack.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100727172437.GE6820@quack.suse.cz> User-Agent: Mutt/1.5.20 (2009-08-17) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 27, 2010 at 07:24:38PM +0200, Jan Kara wrote: > Always returning inode->i_sb->s_bdi wouldn't be a right thing IMHO. > That would file inode for /dev/sda to BDI list of tmpfs mounted on /dev/ > which isn't what you want... It shouldn't. Block device nodes are on the bdev filesystems, and we twist the file->mapping pointer so that all the low-level read/write code always deals with the bdev fs inode, and not the device node filesystem.