From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Grundler Date: Fri, 16 May 2003 17:59:24 +0000 Subject: Re: [Linux-ia64] Re: 64 Bits DMA Addresses for Alloc Consistent Interfaces. Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Fri, May 16, 2003 at 12:36:15PM -0500, James Bottomley wrote: > You mean we need an interface that is called when the CPU hands off the > region to the device and again when the CPU reclaims it (so we always > get the writeback or invalidate in the correct place). yes > How about just adding an ownership attribute to dma_sync..? It would > either be DMA_OWNER_CPU or DMA_OWNER_DEVICE? I prefer davem's suggestion of a different function call (*_to_cpu and *_to_dev) rather than making the same function do completely different things based on parameters. Keeps API documentation and resulting implementations for each smaller. > Of course, retrofitting something like this is going to be fun. It's not so bad. It's really only needed for non-coherent machines. Folks who care about those platforms probably already know where those calls belong. grant