From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263464AbTLJIrh (ORCPT ); Wed, 10 Dec 2003 03:47:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263472AbTLJIrh (ORCPT ); Wed, 10 Dec 2003 03:47:37 -0500 Received: from smithers.nildram.co.uk ([195.112.4.54]:8965 "EHLO smithers.nildram.co.uk") by vger.kernel.org with ESMTP id S263464AbTLJIrg (ORCPT ); Wed, 10 Dec 2003 03:47:36 -0500 Date: Wed, 10 Dec 2003 08:46:32 +0000 From: Joe Thornber To: Nathan Scott Cc: Linux Mailing List Subject: Re: [Patch 1/4] fs.h: b_journal_head Message-ID: <20031210084632.GA476@reti> References: <20031209115806.GA472@reti> <20031209122418.GC472@reti> <20031209234655.GF783@frodo> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20031209234655.GF783@frodo> User-Agent: Mutt/1.5.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 10, 2003 at 10:46:55AM +1100, Nathan Scott wrote: > Could you explain a bit more about when b_private should and > shouldn't be used with this change? Once the io goes through generic_make_request() you shouldn't look at bh->b_private until the io has completed. At which point it will have been correctly set back to the value it had when submitted. The problem with jbd wasn't the fact that it used it, but the fact that it peeked while the io was in flight. This is ugly I know, much cleaner in 2.6 where there is a split between bh and bio. - Joe