From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Yu, Zhang" Subject: One question about the hypercall to translate gfn to mfn. Date: Tue, 09 Dec 2014 18:10:55 +0800 Message-ID: <5486CAAF.9070807@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Paul.Durrant@citrix.com, keir@xen.org, tim@xen.org, JBeulich@suse.com, kevin.tian@intel.com, Xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org Hi all, As you can see, we are pushing our XenGT patches to the upstream. One feature we need in xen is to translate guests' gfn to mfn in XenGT dom0 device model. Here we may have 2 similar solutions: 1> Paul told me(and thank you, Paul :)) that there used to be a hypercall, XENMEM_translate_gpfn_list, which was removed by Keir in commit 2d2f7977a052e655db6748be5dabf5a58f5c5e32, because there was no usage at that time. So solution 1 is to revert this commit. However, since this hypercall was removed ages ago, the reverting met many conflicts, i.e. the gmfn_to_mfn is no longer used in x86, etc. 2> In our project, we defined a new hypercall XENMEM_get_mfn_from_pfn, which has a similar implementation like the previous XENMEM_translate_gpfn_list. One of the major differences is that this newly defined one is only for x86(called in arch_memory_op), so we do not have to worry about the arm side. Does anyone has any suggestions about this? Thanks in advance. :) B.R. Yu