From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id AE5A96B02A7 for ; Sat, 10 Jul 2010 11:11:15 -0400 (EDT) Date: Sat, 10 Jul 2010 17:11:11 +0200 From: Joerg Roedel Subject: Re: [RFC 3/3] mm: iommu: The Virtual Contiguous Memory Manager Message-ID: <20100710151111.GD10080@8bytes.org> References: <1277877350-2147-1-git-send-email-zpfeffer@codeaurora.org> <1277877350-2147-3-git-send-email-zpfeffer@codeaurora.org> <20100701101746.3810cc3b.randy.dunlap@oracle.com> <20100701180241.GA3594@basil.fritz.box> <1278012503.7738.17.camel@c-dwalke-linux.qualcomm.com> <20100701193850.GB3594@basil.fritz.box> <4C2D0FF1.6010206@codeaurora.org> <20100701230056.GD3594@basil.fritz.box> <4C2D847E.5080602@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4C2D847E.5080602@codeaurora.org> Sender: owner-linux-mm@kvack.org To: Zach Pfeffer Cc: Andi Kleen , Daniel Walker , Randy Dunlap , mel@csn.ul.ie, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-ID: On Thu, Jul 01, 2010 at 11:17:34PM -0700, Zach Pfeffer wrote: > Andi Kleen wrote: > > Hmm? dma_map_* does not change any CPU mappings. It only sets up > > DMA mapping(s). > > Sure, but I was saying that iommu_map() doesn't just set up the IOMMU > mappings, its sets up both the iommu and kernel buffer mappings. What do you mean by kernel buffer mappings? > > That assumes that all the IOMMUs on the system support the same page table > > format, right? > > Actually no. Since the VCMM abstracts a page-table as a Virtual > Contiguous Region (VCM) a VCM can be associated with any device, > regardless of their individual page table format. The IOMMU-API abstracts a page-table as a domain which can also be associated with any device (behind an iommu). Joerg -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org