Module iommufd 

Bindings for the Linux iommufd subsystem (/dev/iommu).

Provides safe wrappers around iommufd ioctls for:

• IOAS allocation and DMA mapping (IOMMU_IOAS_ALLOC, IOMMU_IOAS_MAP, IOMMU_IOAS_MAP_FILE, IOMMU_IOAS_UNMAP)
• Hardware page table management (IOMMU_HWPT_ALLOC, IOMMU_HWPT_INVALIDATE)
• Hardware info query (IOMMU_GET_HW_INFO)
• Virtual IOMMU objects (IOMMU_VIOMMU_ALLOC, IOMMU_VDEVICE_ALLOC, IOMMU_VEVENTQ_ALLOC)

The IOAS path supports identity DMA mapping (Phase 4). The HWPT/vIOMMU path supports nested stage 1 translation for VFIO passthrough (Phase 5).

Structs

HwptInvalidateError

Error from IommufdCtx::hwpt_invalidate, pairing the underlying ioctl errno with the kernel’s reported handled-entry count.

IommuHwInfoArmSmmuv3

ARM SMMUv3 hardware information returned by IOMMU_GET_HW_INFO.

IommuHwptArmSmmuv3

ARM SMMUv3 nested HWPT data: the first two double words of the STE.

IommuVeventArmSmmuv3

ARM SMMUv3 virtual event record (256-bit, little-endian).

IommufdCtx

An open iommufd file descriptor (/dev/iommu).

IommufdVeventHeader

Header for each event in a vEVENTQ fd read.

Enums

ViommuAlloc

Outcome of IommufdCtx::viommu_alloc.

Constants

IOMMU_HWPT_ALLOC_NEST_PARENT

Flags for IOMMU_HWPT_ALLOC.

IOMMU_HWPT_DATA_ARM_SMMUV3

HWPT data type: ARM SMMUv3 (nested STE DW0-1).

IOMMU_HWPT_DATA_NONE

HWPT data type: no type-specific data.

IOMMU_HW_INFO_TYPE_ARM_SMMUV3

HW info type: ARM SMMUv3.

IOMMU_IOAS_MAP_FIXED_IOVA

Flags for IOMMU_IOAS_MAP.

IOMMU_IOAS_MAP_READABLE

IOMMU_IOAS_MAP_WRITEABLE

IOMMU_VEVENTQ_FLAG_LOST_EVENTS

IommufdVeventHeader::flags: the queue lost one or more events before this one. No event data follows a header carrying this flag.

IOMMU_VEVENTQ_TYPE_ARM_SMMUV3

vEVENTQ type: ARM SMMUv3.

IOMMU_VIOMMU_INVALIDATE_DATA_ARM_SMMUV3

Invalidation data type for ARM SMMUv3 (via vIOMMU).

IOMMU_VIOMMU_TYPE_ARM_SMMUV3

vIOMMU type: ARM SMMUv3.