From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v3 3/3] xen/arm: introduce XENFEAT_grant_map_identity Date: Thu, 24 Jul 2014 15:47:58 +0100 Message-ID: <53D11C9E.3060700@linaro.org> References: <1406208666-23547-3-git-send-email-stefano.stabellini@eu.citrix.com> <53D1292802000078000258E6@mail.emea.novell.com> <53D137B402000078000259DB@mail.emea.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1XAKJS-0007wN-Ay for xen-devel@lists.xenproject.org; Thu, 24 Jul 2014 14:48:06 +0000 Received: by mail-wi0-f175.google.com with SMTP id ho1so9762484wib.14 for ; Thu, 24 Jul 2014 07:48:04 -0700 (PDT) In-Reply-To: <53D137B402000078000259DB@mail.emea.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jan Beulich , Stefano Stabellini Cc: julien.grall@citrix.com, xen-devel , Ian.Campbell@citrix.com List-Id: xen-devel@lists.xenproject.org On 07/24/2014 03:43 PM, Jan Beulich wrote: >>>> On 24.07.14 at 16:10, wrote: >> On Thu, 24 Jul 2014, Jan Beulich wrote: >>>>>> On 24.07.14 at 15:31, wrote: >>>> --- a/xen/common/grant_table.c >>>> +++ b/xen/common/grant_table.c >>>> @@ -727,7 +727,7 @@ __gnttab_map_grant_ref( >>>> >>>> double_gt_lock(lgt, rgt); >>>> >>>> - if ( gnttab_need_iommu_mapping(ld) ) >>>> + if ( gnttab_need_iommu_mapping(ld) || gnttab_need_identity_mapping(ld) >> ) >>> >>> As before I think this change is pointless. >> >> I don't understand how you propose to solve the problem. > > I think ARM's gnttab_need_iommu_mapping() needs to just be > is_domain_direct_mapped() then. So ARM people will think we need an iommu to add the identity mapping. Why don't we rename gnttab_need_iommu_mapping into gnttab_need_identity_mapping? It would less confusing for both x86 and ARM. Regards, -- Julien Grall