Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753748Ab0GBH37 (ORCPT ); Fri, 2 Jul 2010 03:29:59 -0400 Received: from wolverine01.qualcomm.com ([199.106.114.254]:16015 "EHLO wolverine01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751979Ab0GBH35 (ORCPT ); Fri, 2 Jul 2010 03:29:57 -0400 X-IronPort-AV: E=McAfee;i="5400,1158,6030"; a="46267916" Message-ID: <4C2D9575.9030002@codeaurora.org> Date: Fri, 02 Jul 2010 00:29:57 -0700 From: Zach Pfeffer User-Agent: Thunderbird 2.0.0.23 (X11/20090817) MIME-Version: 1.0 To: Hari Kanigeri 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@jasper.es Subject: Re: [RFC 3/3] mm: iommu: The Virtual Contiguous Memory Manager 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.qualc In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1329 Lines: 28 Hari Kanigeri wrote: >> The VCMM takes the long view. Its designed for a future in which the >> number of IOMMUs will go up and the ways in which these IOMMUs are >> composed will vary from system to system, and may vary at >> runtime. Already, there are ~20 different IOMMU map implementations in >> the kernel. Had the Linux kernel had the VCMM, many of those >> implementations could have leveraged the mapping and topology management >> of a VCMM, while focusing on a few key hardware specific functions (map >> this physical address, program the page table base register). >> > > -- Sounds good. > Did you think of a way to handle the cases where one of the Device > that is using the mapped address crashed ? > How is the physical address unbacked in this case ? Actually the API takes care of that by design. Since the physical space is managed apart from the mapper the mapper can crash and not affect the physical memory allocation. -- Sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/