Implement the virtio-iommu driver following version 0.5 of the specification [1]. Previous version of this code was sent back in April [2], implementing the first public RFC. Since then there has been lots of progress and discussion on the specification side, and I think the driver is in a good shape now. The reason patches 1-3 are only RFC is that I'm waiting on feedback from the Virtio TC to reserve a device ID. List of changes since previous RFC: * Add per-endpoint probe request, for hardware MSI and reserved regions. * Add a virtqueue for the device to report translation faults. Only non-recoverable ones at the moment. * Removed the iommu_map_sg specialization for now, because none of the device drivers I use for testing (virtio, ixgbe and internal DMA engines) seem to use map_sg. This kind of feature is a lot more interesting when accompanied by benchmark numbers, and can be added back during future optimization work. * Many fixes and cleanup The driver works out of the box on DT-based systems, but ACPI support still needs to be tested and discussed. In the specification I proposed IORT tables as a nice candidate for describing the virtual topology. Patches 4 and 5 propose small changes to the IORT driver for instantiating a paravirtualized IOMMU. The IORT node is described in the specification [1]. x86 support will also require some hacks since the driver is based on the IOMMU DMA ops, that x86 doesn't use. Eric's latest QEMU device [3] works with v0.4. For the moment you can use the kvmtool device [4] to test v0.5 on arm64, and inject arbitrary fault with the debug tool. The driver can also be pulled from my Linux tree [5]. [1] https://www.spinics.net/lists/kvm/msg157402.html [2] https://patchwork.kernel.org/patch/9670273/ [3] https://lists.gnu.org/archive/html/qemu-arm/2017-09/msg00413.html [4] git://linux-arm.org/kvmtool-jpb.git virtio-iommu/base [5] git://linux-arm.org/linux-jpb.git virtio-iommu/v0.5-dev Jean-Philippe Brucker (5): iommu: Add virtio-iommu driver iommu/virtio-iommu: Add probe request iommu/virtio-iommu: Add event queue ACPI/IORT: Support paravirtualized IOMMU ACPI/IORT: Move IORT to the ACPI folder drivers/acpi/Kconfig | 3 + drivers/acpi/Makefile | 1 + drivers/acpi/arm64/Kconfig | 3 - drivers/acpi/arm64/Makefile | 1 - drivers/acpi/{arm64 => }/iort.c | 95 ++- drivers/iommu/Kconfig | 12 + drivers/iommu/Makefile | 1 + drivers/iommu/virtio-iommu.c | 1219 +++++++++++++++++++++++++++++++++++++ include/acpi/actbl2.h | 18 +- include/uapi/linux/virtio_ids.h | 1 + include/uapi/linux/virtio_iommu.h | 195 ++++++ 11 files changed, 1537 insertions(+), 12 deletions(-) rename drivers/acpi/{arm64 => }/iort.c (92%) create mode 100644 drivers/iommu/virtio-iommu.c create mode 100644 include/uapi/linux/virtio_iommu.h -- 2.14.3
