From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q5IKcsVx236436 for ; Mon, 18 Jun 2012 15:38:54 -0500 Date: Mon, 18 Jun 2012 15:39:19 -0500 From: Ben Myers Subject: Re: [PATCH 1/9] xfs: separate buffer indexing from block map Message-ID: <20120618203919.GW4721@sgi.com> References: <1339133914-11148-1-git-send-email-david@fromorbit.com> <1339133914-11148-2-git-send-email-david@fromorbit.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1339133914-11148-2-git-send-email-david@fromorbit.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com Hi Dave, On Fri, Jun 08, 2012 at 03:38:26PM +1000, Dave Chinner wrote: > From: Dave Chinner > > To support discontiguous buffers in the buffer cache, we need to > separate the cache index variables from the I/O map. While this is > currently a 1:1 mapping, discontiguous buffer support will break > this relationship. > > However, for caching purposes, we can still treat them the same as a > contiguous buffer - the block number of the first block and the > length of the buffer - as that is still a unique representation. > Also, the only way we will ever access the discontiguous regions of > buffers is via bulding the complete buffer in the first place, so > using the initial block number and entire buffer length is a sane > way to index the buffers. > > Add a block mapping vector construct to the xfs_buf and use it in > the places where we are doing IO instead of the current > b_bn/b_length variables. This patch does not apply even with Jan's patch. Merged it manually. -Ben _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs