This patch series aims to implement VFIO support for platform devices that reside behind an IOMMU. Examples of such devices are devices behind an ARM SMMU, or behind a Samsung Exynos System MMU. This v5 of the VFIO_PLATFORN patch series includes a number of fixes and improvements over the features already implemented in the series. The next version v6 of the VFIO_PLATFORM patch series is planned to introduce more complete functionality with more comprehensive eventfd support. The API used is based on the existing VFIO API that is also used with PCI devices. Only devices that include a basic set of IRQs and memory regions are targeted; devices with complex relationships with other devices on a device tree are not taken into account at this stage. A copy with all the dependencies applied can be cloned from branch vfio-platform-v5 at git@xxxxxxxxxx:virtualopensystems/linux-kvm-arm.git For those who want to apply manually, these patches are based on Alex Williamson's 'next' branch available from https://github.com/awilliam/linux-vfio which includes the multi domain support patches for VFIO_IOMMU_TYPE1. Kim Phillip's driver_override patch for platform bus devices is also included here for convenience. The following IOCTLs have been found to be working on FastModels with an ARM SMMU (MMU400). Testing was based on the ARM PL330 DMA Controller featured on those models. - VFIO_GET_API_VERSION - VFIO_CHECK_EXTENSION - VFIO_GROUP_GET_STATUS - VFIO_GROUP_SET_CONTAINER - VFIO_SET_IOMMU - VFIO_IOMMU_GET_INFO - VFIO_IOMMU_MAP_DMA For this ioctl specifically, a new flag has been added: VFIO_DMA_MAP_FLAG_EXEC. This flag is taken into account on systems with an ARM SMMU. The availability of this flag is exposed via the capability VFIO_IOMMU_PROT_EXEC. The VFIO platform driver proposed here implements the following: - VFIO_GROUP_GET_DEVICE_FD - VFIO_DEVICE_GET_INFO - VFIO_DEVICE_GET_REGION_INFO - VFIO_DEVICE_GET_IRQ_INFO - VFIO_DEVICE_SET_IRQS IRQs are implemented partially using this ioctl. Handling incoming interrupts with an eventfd is supported, as is masking and unmasking. Level sensitive interrupts are automasked. What is not implemented is masking/unmasking via eventfd. More comprehensive support for eventfd functionality is planned for v6. In addition, the VFIO platform driver implements the following through the VFIO device file descriptor: - MMAPing memory regions to the virtual address space of the VFIO user. - Read / write of memory regions directly through the file descriptor. What still needs to be done, includes: - Eventfd for masking/unmasking (IRQFD and IOEVENTFD from the KVM side) - Extend the driver and API for device tree metadata - Support ARM AMBA devices natively - Device specific functionality (e.g. VFIO_DEVICE_RESET) - IOMMUs with nested page tables (Stage 1 & 2 translation on ARM SMMUs) Changes since v4: - Use static offsets for each region in the VFIO device fd - Include patch in the series for the ARM SMMU to expose IOMMU_EXEC availability via IOMMU_CAP_DMA_EXEC - Rebased on VFIO multi domain support: - IOMMU_EXEC is now available if at least one IOMMU in the container supports it - Expose IOMMU_EXEC if available via the capability VFIO_IOMMU_PROT_EXEC - Some bug fixes Changes since v3: - Use Kim Phillips' driver_probe_device() Changes since v2: - Fixed Read/Write and MMAP on device regions - Removed dependency on Device Tree - Interrupts support - Interrupt masking/unmasking - Automask level sensitive interrupts - Introduced VFIO_DMA_MAP_FLAG_EXEC - Code clean ups Antonios Motakis (10): ARM SMMU: Add capability IOMMU_CAP_DMA_EXEC VFIO_IOMMU_TYPE1 for platform bus devices on ARM VFIO_IOMMU_TYPE1: Introduce the VFIO_DMA_MAP_FLAG_EXEC flag VFIO_PLATFORM: Initial skeleton of VFIO support for platform devices VFIO_PLATFORM: Return info for device and its memory mapped IO regions VFIO_PLATFORM: Read and write support for the device fd VFIO_PLATFORM: Support MMAP of MMIO regions VFIO_PLATFORM: Return IRQ info VFIO_PLATFORM: Initial interrupts support VFIO_PLATFORM: Support for maskable and automasked interrupts Kim Phillips (1): driver core: platform: add device binding path 'driver_override' Documentation/ABI/testing/sysfs-bus-platform | 20 ++ drivers/base/platform.c | 46 +++ drivers/iommu/arm-smmu.c | 2 + drivers/vfio/Kconfig | 3 +- drivers/vfio/Makefile | 1 + drivers/vfio/platform/Kconfig | 9 + drivers/vfio/platform/Makefile | 4 + drivers/vfio/platform/vfio_platform.c | 436 ++++++++++++++++++++++++++ drivers/vfio/platform/vfio_platform_irq.c | 289 +++++++++++++++++ drivers/vfio/platform/vfio_platform_private.h | 59 ++++ drivers/vfio/vfio_iommu_type1.c | 39 ++- include/linux/iommu.h | 5 +- include/linux/platform_device.h | 1 + include/uapi/linux/vfio.h | 3 + 14 files changed, 910 insertions(+), 7 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-bus-platform create mode 100644 drivers/vfio/platform/Kconfig create mode 100644 drivers/vfio/platform/Makefile create mode 100644 drivers/vfio/platform/vfio_platform.c create mode 100644 drivers/vfio/platform/vfio_platform_irq.c create mode 100644 drivers/vfio/platform/vfio_platform_private.h -- 1.8.3.2 -- 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
