This series introduces the msi-iommu api used to: - allocate/free resources for MSI IOMMU mapping - set the MSI iova window aperture - map/unmap physical addresses onto MSI IOVAs. - determine whether an msi needs to be iommu mapped - overwrite an msi_msg PA address with its pre-allocated/mapped IOVA
Also a new iommu domain attribute, DOMAIN_ATTR_MSI_GEOMETRY is introduced to report the MSI iova window geometry (aperture and iommu-msi API support). Currently: - iommu driver is supposed to allocate/free MSI mapping resources - VFIO subsystem is supposed to set the MSI IOVA aperture. - The MSI layer is supposed to allocate/free iova mappings and overwrite msi_msg with IOVA at composition time More details & context can be found at: http://www.linaro.org/blog/core-dump/kvm-pciemsi-passthrough-armarm64/ Best Regards Eric Git: complete series available at https://github.com/eauger/linux/tree/v4.7-rc7-passthrough-v11 see part III for wrap-up details. History: v10 -> v11: - no change in the series, just incremented for consistency - added a temporary patch in the branch: "iommu/iova: FIXUP! validate iova_domain input to put_iova_domain" originally sent by Nate and adapted for this use case. This is currently under discussion on the ML. The crash typically occurs in case unsafe interrupts are discovered while allow_unsafe_interrupts is not set. v9 -> v10: - split error management in iommu_msi_set_aperture v8 -> v9: - rename iommu_domain_msi_geometry programmable flag into iommu_msi_supported - introduce msi_apperture_valid helper and use this instead of is_aperture_set v7 -> v8: - The API is retargetted for MSI: renamed msi-iommu all "dma-reserved" namings removed - now implemented upon dma-iommu (get, put, init), ie. reuse iova_cookie, and iova API - msi mapping resources now are guaranteed to exist during the whole iommu domain's lifetime. No need to lock to garantee the cookie integrity - removed alloc/free_reserved_reserved_iova_domain. We now have a single function that sets the aperture, looking like iommu_dma_init_domain. - we now use a list instead of an RB-tree - prot is not propagated anymore at domain creation due to the retargetting for MSI - iommu_domain pointer removed from doorbell_mapping struct - replaced DOMAIN_ATTR_MSI_MAPPING by DOMAIN_ATTR_MSI_GEOMETRY v6 -> v7: - fixed known lock bugs and multiple page sized slots matching (I only have a single MSI frame made of a single page) - reserved_iova_cookie now pointing to a struct that encapsulates the iova domain handle + protection attribute passed from VFIO (Alex' req) - 2 new functions exposed: iommu_msi_mapping_translate_msg, iommu_msi_mapping_desc_to_domain: not sure this is the right location/proto though - iommu_put_reserved_iova now takes a phys_addr_t - everything now is cleanup on iommu_domain destruction RFC v5 -> patch v6: - split to ease the review process - in dma-reserved-api use a spin lock instead of a mutex (reported by Jean-Philippe) - revisit iommu_get_reserved_iova API to pass a size parameter upon Marc's request - Consistently use the page order passed when creating the iova domain. - init reserved_binding_list (reported by Julien) 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 (8): iommu: Add iommu_domain_msi_geometry and DOMAIN_ATTR_MSI_GEOMETRY iommu/arm-smmu: initialize the msi geometry and advertise iommu-msi support iommu: introduce an msi cookie iommu/msi-iommu: initialization iommu/msi-iommu: iommu_msi_[get,put]_doorbell_iova iommu/msi-iommu: iommu_msi_domain iommu/msi-iommu: iommu_msi_msg_pa_to_va iommu/arm-smmu: get/put the msi cookie drivers/iommu/Kconfig | 7 + drivers/iommu/Makefile | 1 + drivers/iommu/arm-smmu-v3.c | 18 ++- drivers/iommu/arm-smmu.c | 18 ++- drivers/iommu/iommu.c | 5 + drivers/iommu/msi-iommu.c | 322 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/iommu.h | 15 +++ include/linux/msi-iommu.h | 144 ++++++++++++++++++++ 8 files changed, 522 insertions(+), 8 deletions(-) create mode 100644 drivers/iommu/msi-iommu.c create mode 100644 include/linux/msi-iommu.h -- 1.9.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
