Add struct iova_allocator, which gives tests a convenient way to generate
legally-accessible IOVAs to map. This allocator traverses the sorted
available IOVA ranges linearly, requires power-of-two size allocations,
and does not support freeing iova allocations. The assumption is that
tests are not IOVA space-bounded, and will not need to recycle IOVAs.
This is based on Alex Williamson's patch series for adding an IOVA
allocator [1].
[1] https://lore.kernel.org/all/20251108212954.26477-1-alex@shazbot.org/
Reviewed-by: David Matlack <dmatlack@google.com>
Tested-by: David Matlack <dmatlack@google.com>
Signed-off-by: Alex Mastro <amastro@fb.com>
Link: https://lore.kernel.org/r/20251111-iova-ranges-v3-3-7960244642c5@fb.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
VFIO selftests need to map IOVAs from legally accessible ranges, which
could vary between hardware. Tests in vfio_dma_mapping_test.c are making
excessively strong assumptions about which IOVAs can be mapped.
Add vfio_iommu_iova_ranges(), which queries IOVA ranges from the
IOMMUFD or VFIO container associated with the device. The queried ranges
are normalized to IOMMUFD's iommu_iova_range representation so that
handling of IOVA ranges up the stack can be implementation-agnostic.
iommu_iova_range and vfio_iova_range are equivalent, so bias to using the
new interface's struct.
Query IOMMUFD's ranges with IOMMU_IOAS_IOVA_RANGES.
Query VFIO container's ranges with VFIO_IOMMU_GET_INFO and
VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE.
The underlying vfio_iommu_type1_info buffer-related functionality has
been kept generic so the same helpers can be used to query other
capability chain information, if needed.
Reviewed-by: David Matlack <dmatlack@google.com>
Tested-by: David Matlack <dmatlack@google.com>
Signed-off-by: Alex Mastro <amastro@fb.com>
Link: https://lore.kernel.org/r/20251111-iova-ranges-v3-1-7960244642c5@fb.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
Add __vfio_pci_dma_*() helpers which return -errno from the underlying
ioctls.
Add __vfio_pci_dma_unmap_all() to test more unmapping code paths. Add an
out unmapped arg to report the unmapped byte size.
The existing vfio_pci_dma_*() functions, which are intended for
happy-path usage (assert on failure) are now thin wrappers on top of the
double-underscore helpers.
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Alex Mastro <amastro@fb.com>
Link: https://lore.kernel.org/r/20251028-fix-unmap-v6-4-2542b96bcc8e@fb.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
Add a new IOMMU mode for using iommufd directly. In this mode userspace
opens /dev/iommu and binds it to a device FD acquired through
/dev/vfio/devices/vfioX.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-29-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add new IOMMU modes for using iommufd in compatibility mode with
VFIO_TYPE1_IOMMU and VFIO_TYPE1v2_IOMMU.
In these modes, VFIO selftests will open /dev/iommu and treats it as a
container FD (as if it had opened /dev/vfio/vfio) and the kernel
translates the container ioctls to iommufd calls transparently.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-28-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a new IOMMU mode for using VFIO_TYPE1v2_IOMMU.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-27-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Automatically replicate vfio_dma_mapping_test and vfio_pci_driver_test
across all supported IOMMU modes using fixture variants. Both of these
tests exercise DMA mapping to some degree so having automatic coverage
across all IOMMU modes will help catch bugs.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-26-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Encapsulate the "IOMMU mode" a test should use behind a new struct.
In the future this will be used to support other types of IOMMUs besides
VFIO_TYPE1_IOMMU, and allow users to select the mode on the command
line.
No functional change intended.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-25-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Move the helper function to get the VFIO cdev path to libvfio so that it
can be used in libvfio in a subsequent commit.
No functional change intended.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-24-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a driver framework to VFIO selftests, so that devices can generate
DMA and interrupts in a common way that can be then utilized by tests.
This will enable VFIO selftests to exercise real hardware DMA and
interrupt paths, without needing any device-specific code in the test
itself.
Subsequent commits will introduce drivers for specific devices.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-13-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a helper function for matching a device against a given vendor and
device ID. This will be used in a subsequent commit to match devices
against drivers.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-12-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Make it possible to assert that a given MSI eventfd did _not_ fire by
adding a helper to mark an eventfd non-blocking. Demonstrate this in
vfio_pci_device_test by asserting the MSI eventfd did not fire before
vfio_pci_irq_trigger().
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-11-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Keep track of the list of DMA regions that are mapped into the device
using a linked list and a new struct vfio_dma_region and use that to add
{__,}to_iova() for converting host virtual addresses into IOVAs.
This will be used in a subsequent commit to map multiple DMA regions
into a device that are then used by drivers.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-10-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a test to vfio_pci_device_test which resets the device. If reset is
not supported by the device, the test is skipped.
Signed-off-by: Josh Hilke <jrhilke@google.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-7-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a basic helper library to be used by VFIO selftests.
The basic unit of the library is struct vfio_pci_device, which
represents a single PCI device that is bound to the vfio-pci driver. The
library currently only supports a single device per group and container,
and VFIO IOMMU types.
The code in this library was heavily based on prior work done by
Raghavendra Rao Ananta <rananta@google.com>, and the VFIO_ASSERT*()
macros were written by Vipin Sharma <vipinsh@google.com>.
Separate that Makefile rules for building the library into a separate
script so that the library can be built by and linked into KVM selftests
in a subsequent commit.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-3-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Alex Mastro
David Matlack
Josh Hilke