On Mon, 10 Nov 2025 13:10:42 -0800
Alex Mastro <[email protected]> wrote:
> Use the newly available vfio_pci_iova_ranges() to determine the last
> legal IOVA, and use this as the basis for vfio_dma_map_limit_test tests.
>
> Fixes: de8d1f2fd5a5 ("vfio: selftests: add end of address space DMA map/unmap
> tests")
> Signed-off-by: Alex Mastro <[email protected]>
> ---
> tools/testing/selftests/vfio/vfio_dma_mapping_test.c | 17 +++++++++++++++--
> 1 file changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
> b/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
> index 4f1ea79a200c..37c2a342df8d 100644
> --- a/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
> +++ b/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
> @@ -3,6 +3,8 @@
> #include <sys/mman.h>
> #include <unistd.h>
>
> +#include <uapi/linux/types.h>
> +#include <linux/iommufd.h>
> #include <linux/limits.h>
> #include <linux/mman.h>
> #include <linux/sizes.h>
> @@ -219,7 +221,10 @@ FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES();
> FIXTURE_SETUP(vfio_dma_map_limit_test)
> {
> struct vfio_dma_region *region = &self->region;
> + struct iommu_iova_range *ranges;
> u64 region_size = getpagesize();
> + iova_t last_iova;
> + size_t nranges;
>
> /*
> * Over-allocate mmap by double the size to provide enough backing vaddr
> @@ -232,8 +237,13 @@ FIXTURE_SETUP(vfio_dma_map_limit_test)
> MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> ASSERT_NE(region->vaddr, MAP_FAILED);
>
> - /* One page prior to the end of address space */
> - region->iova = ~(iova_t)0 & ~(region_size - 1);
> + ranges = vfio_pci_iova_ranges(self->device, &nranges);
> + VFIO_ASSERT_NOT_NULL(ranges);
> + last_iova = ranges[nranges - 1].last;
Building on the imposed requirement of ordered ranges. Thanks,
Alex
> + free(ranges);
> +
> + /* One page prior to the last iova */
> + region->iova = last_iova & ~(region_size - 1);
> region->size = region_size;
> }
>
> @@ -276,6 +286,9 @@ TEST_F(vfio_dma_map_limit_test, overflow)
> struct vfio_dma_region *region = &self->region;
> int rc;
>
> + if (region->iova != (~(iova_t)0 & ~(region->size - 1)))
> + SKIP(return, "IOMMU address space insufficient for overflow
> test");
> +
> region->size = self->mmap_size;
>
> rc = __vfio_pci_dma_map(self->device, region);
>
