This patch-series aims at enabling Nested stage translation in guests using virtio-iommu as the paravirtualized iommu. The backend is supported with Arm SMMU-v3 that provides nested stage-1 and stage-2 translation.
This series derives its purpose from various efforts happening to add support for Shared Virtual Addressing (SVA) in host and guest. On Arm, most of the support for SVA has already landed. The support for nested stage translation and fault reporting to guest has been proposed [1]. The related changes required in VFIO [2] framework have also been put forward. This series proposes changes in virtio-iommu to program PASID tables and related stage-1 page tables. A simple iommu-pasid-table library is added for this purpose that interacts with vendor drivers to allocate and populate PASID tables. In Arm SMMUv3 we propose to pull the Context Descriptor (CD) management code out of the arm-smmu-v3 driver and add that as a glue vendor layer to support allocating CD tables, and populating them with right values. These CD tables are essentially the PASID tables and contain stage-1 page table configurations too. A request to setup these CD tables come from virtio-iommu driver using the iommu-pasid-table library when running on Arm. The virtio-iommu then pass these PASID tables to the host using the right virtio backend and support in VMM. For testing we have added necessary support in kvmtool. The changes in kvmtool are based on virtio-iommu development branch by Jean-Philippe Brucker [3]. The tested kernel branch contains following in the order bottom to top on the git hash - a) v5.11-rc3 b) arm-smmu-v3 [1] and vfio [2] changes from Eric to add nested page table support for Arm. c) Smmu test engine patches from Jean-Philippe's branch [4] d) This series e) Domain nesting info patches [5][6][7]. f) Changes to add arm-smmu-v3 specific nesting info (to be sent to the list). This kernel is tested on Neoverse reference software stack with Fixed virtual platform. Public version of the software stack and FVP is available here[8][9]. A big thanks to Jean-Philippe for his contributions towards this work and for his valuable guidance. [1] https://lore.kernel.org/linux-iommu/20201118112151.25412-1-eric.au...@redhat.com/T/ [2] https://lore.kernel.org/kvmarm/20201116110030.32335-12-eric.au...@redhat.com/T/ [3] https://jpbrucker.net/git/kvmtool/log/?h=virtio-iommu/devel [4] https://jpbrucker.net/git/linux/log/?h=sva/smmute [5] https://lore.kernel.org/kvm/1599734733-6431-2-git-send-email-yi.l....@intel.com/ [6] https://lore.kernel.org/kvm/1599734733-6431-3-git-send-email-yi.l....@intel.com/ [7] https://lore.kernel.org/kvm/1599734733-6431-4-git-send-email-yi.l....@intel.com/ [8] https://developer.arm.com/tools-and-software/open-source-software/arm-platforms-software/arm-ecosystem-fvps [9] https://git.linaro.org/landing-teams/working/arm/arm-reference-platforms.git/about/docs/rdn1edge/user-guide.rst Jean-Philippe Brucker (6): iommu/virtio: Add headers for table format probing iommu/virtio: Add table format probing iommu/virtio: Add headers for binding pasid table in iommu iommu/virtio: Add support for INVALIDATE request iommu/virtio: Attach Arm PASID tables when available iommu/virtio: Add support for Arm LPAE page table format Vivek Gautam (9): iommu/arm-smmu-v3: Create a Context Descriptor library iommu: Add a simple PASID table library iommu/arm-smmu-v3: Update drivers to work with iommu-pasid-table iommu/arm-smmu-v3: Update CD base address info for user-space iommu/arm-smmu-v3: Set sync op from consumer driver of cd-lib iommu: Add asid_bits to arm smmu-v3 stage1 table info iommu/virtio: Update table format probing header iommu/virtio: Prepare to add attach pasid table infrastructure iommu/virtio: Update fault type and reason info for viommu fault drivers/iommu/arm/arm-smmu-v3/Makefile | 2 +- .../arm/arm-smmu-v3/arm-smmu-v3-cd-lib.c | 283 +++++++ .../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 16 +- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 268 +------ drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 4 +- drivers/iommu/iommu-pasid-table.h | 140 ++++ drivers/iommu/virtio-iommu.c | 692 +++++++++++++++++- include/uapi/linux/iommu.h | 2 +- include/uapi/linux/virtio_iommu.h | 158 +++- 9 files changed, 1303 insertions(+), 262 deletions(-) create mode 100644 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-cd-lib.c create mode 100644 drivers/iommu/iommu-pasid-table.h -- 2.17.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu