This series implements the MSI address mapping/unmapping in the MSI sub-system. binding happens on msi_domain_set_affinity, msi_domain_activate, msi_domain_deactivate. a new MSI domain info flag value is introduced to report whether the msi domain implements IRQ remapping. GIC v3 ITS is the first MSI controller advertising it. This flag value will be used by VFIO subsystem to determine whether MSI forwarding is safe. More details & context can be found at: http://www.linaro.org/blog/core-dump/kvm-pciemsi-passthrough-armarm64/ Best Regards Eric Applies on top of part 1/3. Git: complete series available at https://git.linaro.org/people/eric.auger/linux.git/shortlog/refs/heads/v4.6-rc1-pcie-passthrough-v6 History: RFC v5 -> patch v6: - split to ease the review process - rebase on default iommu domain code (irq_data_to_msi_mapping_domain checks IOMMU_DOMAIN_DMA type) - fix unmap sequence on msi_domain_set_affinity (reported by Marc): unmap the previous doorbell when the new one has been mapped & written to the device, ie. irq_chip_write_msi_msg. - "msi: msi_compose wrapper removed" following change above - add size parameter to iommu_get_reserved_iova API following Marc's request 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 (4): msi: Add a new MSI_FLAG_IRQ_REMAPPING flag irqchip/gic-v3-its: ITS advertises MSI_FLAG_IRQ_REMAPPING msi: export msi_get_domain_info msi: IOMMU map the doorbell address when needed drivers/irqchip/irq-gic-v3-its-pci-msi.c | 3 +- drivers/irqchip/irq-gic-v3-its-platform-msi.c | 3 +- include/linux/msi.h | 17 ++++ kernel/irq/msi.c | 124 ++++++++++++++++++++++++++ 4 files changed, 145 insertions(+), 2 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
