Several new features and uAPI for iommufd:
- IOMMU_IOAS_MAP_FILE allows passing in a file descriptor as the backing
memory for an iommu mapping. To date VFIO/iommufd have used VMA's and
pin_user_pages(), this now allows using memfds and memfd_pin_folios().
Notably this creates a pure folio path from the memfd to the iommu page
table where memory is never broken down to PAGE_SIZE.
- IOMMU_IOAS_CHANGE_PROCESS moves the pinned page accounting between two
processes. Combined with the above this allows iommufd to support a VMM
re-start using exec() where something like qemu would exec() a new
version of itself and fd pass the memfds/iommufd/etc to the new
process. The memfd allows DMA access to the memory to continue while
the new process is getting setup, and the CHANGE_PROCESS updates all
the accounting.
- Support for fault reporting to userspace on non-PRI HW, such as ARM
stall-mode embedded devices.
- IOMMU_VIOMMU_ALLOC introduces the concept of a HW/driver backed virtual
iommu. This will be used by VMMs to access hardware features that are
contained with in a VM. The first use is to inform the kernel of the
virtual SID to physical SID mapping when issuing SID based invalidation
on ARM. Further uses will tie HW features that are directly accessed by
the VM, such as invalidation queue assignment and others.
- IOMMU_VDEVICE_ALLOC informs the kernel about the mapping of virtual
device to physical device within a VIOMMU. Minimially this is used to
translate VM issued cache invalidation commands from virtual to physical
device IDs.
- Enhancements to IOMMU_HWPT_INVALIDATE and IOMMU_HWPT_ALLOC to work with
the VIOMMU
- ARM SMMuv3 support for nested translation. Using the VIOMMU and VDEVICE
the driver can model this HW's behavior for nested translation. This
includes a shared branch from Will.
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Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd
Pull iommufd updates from Jason Gunthorpe:
"Several new features and uAPI for iommufd:
- IOMMU_IOAS_MAP_FILE allows passing in a file descriptor as the
backing memory for an iommu mapping. To date VFIO/iommufd have used
VMA's and pin_user_pages(), this now allows using memfds and
memfd_pin_folios(). Notably this creates a pure folio path from the
memfd to the iommu page table where memory is never broken down to
PAGE_SIZE.
- IOMMU_IOAS_CHANGE_PROCESS moves the pinned page accounting between
two processes. Combined with the above this allows iommufd to
support a VMM re-start using exec() where something like qemu would
exec() a new version of itself and fd pass the memfds/iommufd/etc
to the new process. The memfd allows DMA access to the memory to
continue while the new process is getting setup, and the
CHANGE_PROCESS updates all the accounting.
- Support for fault reporting to userspace on non-PRI HW, such as ARM
stall-mode embedded devices.
- IOMMU_VIOMMU_ALLOC introduces the concept of a HW/driver backed
virtual iommu. This will be used by VMMs to access hardware
features that are contained with in a VM. The first use is to
inform the kernel of the virtual SID to physical SID mapping when
issuing SID based invalidation on ARM. Further uses will tie HW
features that are directly accessed by the VM, such as invalidation
queue assignment and others.
- IOMMU_VDEVICE_ALLOC informs the kernel about the mapping of virtual
device to physical device within a VIOMMU. Minimially this is used
to translate VM issued cache invalidation commands from virtual to
physical device IDs.
- Enhancements to IOMMU_HWPT_INVALIDATE and IOMMU_HWPT_ALLOC to work
with the VIOMMU
- ARM SMMuv3 support for nested translation. Using the VIOMMU and
VDEVICE the driver can model this HW's behavior for nested
translation. This includes a shared branch from Will"
* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (51 commits)
iommu/arm-smmu-v3: Import IOMMUFD module namespace
iommufd: IOMMU_IOAS_CHANGE_PROCESS selftest
iommufd: Add IOMMU_IOAS_CHANGE_PROCESS
iommufd: Lock all IOAS objects
iommufd: Export do_update_pinned
iommu/arm-smmu-v3: Support IOMMU_HWPT_INVALIDATE using a VIOMMU object
iommu/arm-smmu-v3: Allow ATS for IOMMU_DOMAIN_NESTED
iommu/arm-smmu-v3: Use S2FWB for NESTED domains
iommu/arm-smmu-v3: Support IOMMU_DOMAIN_NESTED
iommu/arm-smmu-v3: Support IOMMU_VIOMMU_ALLOC
Documentation: userspace-api: iommufd: Update vDEVICE
iommufd/selftest: Add vIOMMU coverage for IOMMU_HWPT_INVALIDATE ioctl
iommufd/selftest: Add IOMMU_TEST_OP_DEV_CHECK_CACHE test command
iommufd/selftest: Add mock_viommu_cache_invalidate
iommufd/viommu: Add iommufd_viommu_find_dev helper
iommu: Add iommu_copy_struct_from_full_user_array helper
iommufd: Allow hwpt_id to carry viommu_id for IOMMU_HWPT_INVALIDATE
iommu/viommu: Add cache_invalidate to iommufd_viommu_ops
iommufd/selftest: Add IOMMU_VDEVICE_ALLOC test coverage
iommufd/viommu: Add IOMMUFD_OBJ_VDEVICE and IOMMU_VDEVICE_ALLOC ioctl
...
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