From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH 1/16] Spidernet DMA coalescing Date: Thu, 7 Dec 2006 10:11:51 +0000 Message-ID: <20061207101151.GB27904@infradead.org> References: <20061206223223.GH17931@austin.ibm.com> <20061206232745.GA4649@austin.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andrew Morton , jgarzik@pobox.com, netdev@vger.kernel.org, linuxppc-dev@ozlabs.org, James K Lewis , Arnd Bergmann , Geoff Levand Return-path: Received: from pentafluge.infradead.org ([213.146.154.40]:39617 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031934AbWLGKMC (ORCPT ); Thu, 7 Dec 2006 05:12:02 -0500 To: Linas Vepstas Content-Disposition: inline In-Reply-To: <20061206232745.GA4649@austin.ibm.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Dec 06, 2006 at 05:27:45PM -0600, Linas Vepstas wrote: > > The current driver code performs 512 DMA mappings of a bunch of > 32-byte structures. This is silly, as they are all in contiguous > memory. Ths patch changes the code to DMA map the entie area > with just one call. This is still wrong. The descriptor array must be in dma_alloc_coherent memory, not a streaming mapping. (I also think I pointed this out a while ago when I made dma_alloc_coherent node-aware)