This series allows a virtualizer to program the nested stage mode. This is useful when both the host and the guest are exposed with an SMMUv3 and a PCI device is assigned to the guest using VFIO. In this mode, the physical IOMMU must be programmed to translate the two stages: the one set up by the guest (IOVA -> GPA) and the one set up by the host VFIO driver as part of the assignment process (GPA -> HPA). On Intel, this is traditionnaly achieved by combining the 2 stages into a single physical stage. However this relies on the capability to trap on each guest translation structure update. This is possible by using the VTD Caching Mode. Unfortunately the ARM SMMUv3 does not offer a similar mechanism. However, the ARM SMMUv3 architecture supports 2 physical stages! Those were devised exactly with that use case in mind. Assuming the HW implements both stages (optional), the guest now can use stage 1 while the host uses stage 2. This assumes the virtualizer has means to propagate guest settings to the host SMMUv3 driver. This series brings this VFIO/IOMMU infrastructure. Those services are: - bind the guest stage 1 configuration to the stream table entry - propagate guest TLB invalidations - bind MSI IOVAs - propagate faults collected at physical level up to the virtualizer This series largely reuses the user API and infrastructure originally devised for SVA/SVM and patches submitted by Jacob, Yi Liu, Tianyu in [1-3] and Jean-Philippe [4]. This proof of concept also aims at illustrating how this API/infrastructure would need to evolve to support this nested stage SMMUv3 use case. Best Regards Eric This series can be found at: https://github.com/eauger/linux/tree/v4.19-rc4-2stage-rfc-v2 This was tested on Qualcomm HW featuring SMMUv3 and with adapted QEMU vSMMUv3. References: [1] [PATCH v5 00/23] IOMMU and VT-d driver support for Shared Virtual Address (SVA) https://lwn.net/Articles/754331/ [2] [RFC PATCH 0/8] Shared Virtual Memory virtualization for VT-d (VFIO part) https://lists.linuxfoundation.org/pipermail/iommu/2017-April/021475.html [3] [RFC PATCH 0/3] VFIO: Report IOMMU fault event to userspace https://www.spinics.net/lists/kvm/msg145280.html [4] [v2,00/40] Shared Virtual Addressing for the IOMMU https://patchwork.ozlabs.org/cover/912129/ History: v1 -> v2: - Added the fault reporting capability - asid properly passed on invalidation (fix assignment of multiple devices) - see individual change logs for more info Eric Auger (11): iommu: Introduce bind_guest_msi vfio: VFIO_IOMMU_BIND_MSI iommu/smmuv3: Get prepared for nested stage support iommu/smmuv3: Implement bind_pasid_table iommu/smmuv3: Implement cache_invalidate dma-iommu: Implement NESTED_MSI cookie iommu/smmuv3: Implement bind_guest_msi vfio: VFIO_IOMMU_SET_FAULT_EVENTFD vfio: VFIO_IOMMU_GET_FAULT_EVENTS vfio: Document nested stage control iommu/smmuv3: Report non recoverable faults Jacob Pan (4): iommu: Introduce bind_pasid_table API iommu: introduce device fault data driver core: add per device iommu param iommu: introduce device fault report API Jean-Philippe Brucker (2): iommu/arm-smmu-v3: Link domains and devices iommu/arm-smmu-v3: Maintain a SID->device structure Liu, Yi L (3): iommu: Introduce cache_invalidate API vfio: VFIO_IOMMU_BIND_PASID_TABLE vfio: VFIO_IOMMU_CACHE_INVALIDATE Documentation/vfio.txt | 60 ++++ drivers/iommu/arm-smmu-v3.c | 476 ++++++++++++++++++++++++++++++-- drivers/iommu/dma-iommu.c | 97 ++++++- drivers/iommu/iommu.c | 196 ++++++++++++- drivers/vfio/vfio_iommu_type1.c | 269 ++++++++++++++++++ include/linux/device.h | 3 + include/linux/dma-iommu.h | 11 + include/linux/iommu.h | 134 ++++++++- include/uapi/linux/iommu.h | 237 ++++++++++++++++ include/uapi/linux/vfio.h | 48 ++++ 10 files changed, 1501 insertions(+), 30 deletions(-) create mode 100644 include/uapi/linux/iommu.h -- 2.17.1 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
