This series allows the user-space to register a reserved IOVA domain. This completes the kernel integration of the whole functionality on top of part 1 & 2. We reuse the VFIO DMA MAP ioctl with a new flag to bridge to the dma-reserved-iommu API. The number of IOVA pages to provision for MSI binding is reported through the VFIO_IOMMU_GET_INFO iotcl. vfio_iommu_type1 checks if the MSI mapping is safe when attaching the vfio group to the container (allow_unsafe_interrupts modality). On ARM/ARM64, the IOMMU does not astract IRQ remapping. the modality is abstracted on MSI controller side. The GICv3 ITS is the first controller advertising the modality. More details & context can be found at: http://www.linaro.org/blog/core-dump/kvm-pciemsi-passthrough-armarm64/ Best Regards Eric Testing: - functional on ARM64 AMD Overdrive HW (single GICv2m frame) with x Intel e1000e PCIe card x Intel X540-T2 (SR-IOV capable) - Not tested: ARM GICv3 ITS References: [1] [RFC 0/2] VFIO: Add virtual MSI doorbell support (https://lkml.org/lkml/2015/7/24/135) [2] [RFC PATCH 0/6] vfio: Add interface to map MSI pages (https://lists.cs.columbia.edu/pipermail/kvmarm/2015-September/016607.html) [3] [PATCH v2 0/3] Introduce MSI hardware mapping for VFIO (http://permalink.gmane.org/gmane.comp.emulators.kvm.arm.devel/3858) Git: complete series available at https://git.linaro.org/people/eric.auger/linux.git/shortlog/refs/heads/v4.6-rc1-pcie-passthrough-v6 previous version at https://git.linaro.org/people/eric.auger/linux.git/shortlog/refs/heads/v4.5-rc6-pcie-passthrough-rfcv5 QEMU Integration: [RFC v2 0/8] KVM PCI/MSI passthrough with mach-virt (http://lists.gnu.org/archive/html/qemu-arm/2016-01/msg00444.html) https://git.linaro.org/people/eric.auger/qemu.git/shortlog/refs/heads/v2.5.0-pci-passthrough-rfc-v2 History: RFC v5 -> patch v6: - split to ease the review process RFC v4 -> RFC v5: - take into account Thomas' comments on MSI related patches - split "msi: IOMMU map the doorbell address when needed" - increase readability and add comments - fix style issues - split "iommu: Add DOMAIN_ATTR_MSI_MAPPING attribute" - platform ITS now advertises IOMMU_CAP_INTR_REMAP - fix compilation issue with CONFIG_IOMMU API unset - arm-smmu-v3 now advertises DOMAIN_ATTR_MSI_MAPPING RFC v3 -> v4: - Move doorbell mapping/unmapping in msi.c - fix ref count issue on set_affinity: in case of a change in the address the previous address is decremented - doorbell map/unmap now is done on msi composition. Should allow the use case for platform MSI controllers - create dma-reserved-iommu.h/c exposing/implementing a new API dedicated to reserved IOVA management (looking like dma-iommu glue) - series reordering to ease the review: - first part is related to IOMMU - second related to MSI sub-system - third related to VFIO (except arm-smmu IOMMU_CAP_INTR_REMAP removal) - expose the number of requested IOVA pages through VFIO_IOMMU_GET_INFO [this partially addresses Marc's comments on iommu_get/put_single_reserved size/alignment problematic - which I did not ignore - but I don't know how much I can do at the moment] RFC v2 -> RFC v3: - should fix wrong handling of some CONFIG combinations: CONFIG_IOVA, CONFIG_IOMMU_API, CONFIG_PCI_MSI_IRQ_DOMAIN - fix MSI_FLAG_IRQ_REMAPPING setting in GICv3 ITS (although not tested) PATCH v1 -> RFC v2: - reverted to RFC since it looks more reasonable ;-) the code is split between VFIO, IOMMU, MSI controller and I am not sure I did the right choices. Also API need to be further discussed. - iova API usage in arm-smmu.c. - MSI controller natively programs the MSI addr with either the PA or IOVA. This is not done anymore in vfio-pci driver as suggested by Alex. - check irq remapping capability of the group RFC v1 [2] -> PATCH v1: - use the existing dma map/unmap ioctl interface with a flag to register a reserved IOVA range. Use the legacy Rb to store this special vfio_dma. - a single reserved IOVA contiguous region now is allowed - use of an RB tree indexed by PA to store allocated reserved slots - use of a vfio_domain iova_domain to manage iova allocation within the window provided by the userspace - vfio alloc_map/unmap_free take a vfio_group handle - vfio_group handle is cached in vfio_pci_device - add ref counting to bindings - user modality enabled at the end of the series Eric Auger (5): vfio: introduce VFIO_IOVA_RESERVED vfio_dma type vfio: allow the user to register reserved iova range for MSI mapping vfio/type1: also check IRQ remapping capability at msi domain iommu/arm-smmu: do not advertise IOMMU_CAP_INTR_REMAP vfio/type1: return MSI mapping requirements with VFIO_IOMMU_GET_INFO drivers/iommu/arm-smmu.c | 2 +- drivers/vfio/vfio_iommu_type1.c | 349 +++++++++++++++++++++++++++++++++++++++- include/uapi/linux/vfio.h | 14 +- 3 files changed, 358 insertions(+), 7 deletions(-) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
