From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: Re: [PATCH v4 0/5] vfio: type1: support for ARM SMMUS with VFIO_IOMMU_TYPE1 Date: Tue, 03 Mar 2015 11:01:55 -0700 Message-ID: <1425405715.5200.217.camel@redhat.com> References: <1425315507-29661-1-git-send-email-b.reynal@virtualopensystems.com> <54F5F37E.2070002@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 20AE347880 for ; Tue, 3 Mar 2015 12:56:00 -0500 (EST) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5+9gF7hfEUu0 for ; Tue, 3 Mar 2015 12:55:58 -0500 (EST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id B381F47879 for ; Tue, 3 Mar 2015 12:55:58 -0500 (EST) In-Reply-To: <54F5F37E.2070002@linaro.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Eric Auger Cc: iommu@lists.linux-foundation.org, tech@virtualopensystems.com, kvmarm@lists.cs.columbia.edu List-Id: kvmarm@lists.cs.columbia.edu On Tue, 2015-03-03 at 18:46 +0100, Eric Auger wrote: > Hi Baptiste, > > In "vfio: type1: implement the VFIO_DMA_MAP_FLAG_NOEXEC flag" you still > kept domain->caps |= IOMMU_CAP_NOEXEC so potentially overwriting 1<< > IOMMU_CAP_CACHE_COHERENCY I guess. > > Sorry I do not have this 4th patch file in my mailbox. > > Best Regards > > Eric > > if (iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY)) > domain->caps |= (1 << IOMMU_CAP_CACHE_COHERENCY); > > if (iommu_capable(bus, IOMMU_CAP_NOEXEC)) > domain->caps |= IOMMU_CAP_NOEXEC; Patch 4/5 has problems too, vfio_domains_have_iommu_cap() is called with IOMMU_CAP_CACHE_COHERENCY, but nobody is shifting that into a bitmap before doing the comparison. TBH, I don't see the point of creating this artificial bitmap out of the capabilities. Why can't we keep everything in the domain of actual flags passed to iommu_ops functions? It's just silly to test for cached capability and re-invent the mapping flags on every mapping call and it's just as easy to generalize a test using the actual flags as to use the capabilities, perhaps easier. Thanks, Alex > On 03/02/2015 05:58 PM, Baptiste Reynal wrote: > > This patch series makes the VFIO_IOMMU_TYPE1 driver buildable on ARM, so it > > may be used with ARM SMMUs. It also adds support for the IOMMU_NOEXEC flag > > supported by SMMUs adhering to the ARM SMMU specification so the VFIO user can > > specify whether the target memory can be executed by the device behind the > > SMMU. > > > > Changes from v3: > > - Rebased on linux v4.0-rc1 > > - Use bit shifting for domain->caps > > - Baptiste Reynal is the new maintainer of this serie > > Changes from v2: > > - Rebased on latest iommu/next branch by Joerg Roedel > > Changes from v1: > > - Bugfixes and corrected some typos > > - Use enum for VFIO IOMMU driver capabilities > > > > Antonios Motakis (5): > > vfio: implement iommu driver capabilities with an enum > > vfio: introduce the VFIO_DMA_MAP_FLAG_NOEXEC flag > > vfio: type1: replace domain wide protection flags with supported > > capabilities > > vfio: type1: replace vfio_domains_have_iommu_cache with generic > > function > > vfio: type1: implement the VFIO_DMA_MAP_FLAG_NOEXEC flag > > > > drivers/vfio/vfio_iommu_type1.c | 91 +++++++++++++++++++++++++++++------------ > > include/uapi/linux/vfio.h | 30 ++++++++------ > > 2 files changed, 81 insertions(+), 40 deletions(-) > > > > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu