From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 2.6.30 5/5] cxgb3: map entire Rx page, feed map+offset to Rx ring. Date: Fri, 27 Mar 2009 00:53:42 -0700 (PDT) Message-ID: <20090327.005342.73932167.davem@davemloft.net> References: <20090327023909.32137.93884.stgit@speedy5> <20090327023929.32137.65704.stgit@speedy5> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, swise@opengridcomputing.com To: divy@chelsio.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:36378 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1756321AbZC0Hxz (ORCPT ); Fri, 27 Mar 2009 03:53:55 -0400 In-Reply-To: <20090327023929.32137.65704.stgit@speedy5> Sender: netdev-owner@vger.kernel.org List-ID: From: Divy Le Ray Date: Thu, 26 Mar 2009 19:39:29 -0700 > From: Divy Le Ray > > DMA mapping can be expensive in the presence of iommus. > Reduce the Rx iommu activity by mapping an entire page, and provide the H/W > the mapped address + offset of the current page chunk. > Reserve bits at the end of the page to track mapping references, so the page > can be unmapped. > > Signed-off-by: Divy Le Ray Applied.