Commit de8d1f2f authored by Alex Mastro's avatar Alex Mastro Committed by Alex Williamson
Browse files

vfio: selftests: add end of address space DMA map/unmap tests 



Add tests which validate dma map/unmap at the end of address space. Add
negative test cases for checking that overflowing ioctl args fail with
the expected errno.

Reviewed-by: default avatarDavid Matlack <dmatlack@google.com>
Signed-off-by: default avatarAlex Mastro <amastro@fb.com>
Link: https://lore.kernel.org/r/20251028-fix-unmap-v6-5-2542b96bcc8e@fb.com


Signed-off-by: default avatarAlex Williamson <alex@shazbot.org>
parent 16950b60

tools/testing/selftests/vfio/vfio_dma_mapping_test.c

+90 −0
Original line number Diff line number Diff line
@@ -112,6 +112,8 @@ FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(anonymous, 0, 0); 
FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(anonymous_hugetlb_2mb, SZ_2M, MAP_HUGETLB | MAP_HUGE_2MB);

FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(anonymous_hugetlb_1gb, SZ_1G, MAP_HUGETLB | MAP_HUGE_1GB);



#undef FIXTURE_VARIANT_ADD_IOMMU_MODE



FIXTURE_SETUP(vfio_dma_mapping_test)

{

	self->device = vfio_pci_device_init(device_bdf, variant->iommu_mode);
@@ -195,6 +197,94 @@ TEST_F(vfio_dma_mapping_test, dma_map_unmap) 
	ASSERT_TRUE(!munmap(region.vaddr, size));

}



FIXTURE(vfio_dma_map_limit_test) {

	struct vfio_pci_device *device;

	struct vfio_dma_region region;

	size_t mmap_size;

};



FIXTURE_VARIANT(vfio_dma_map_limit_test) {

	const char *iommu_mode;

};



#define FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode)			       \

FIXTURE_VARIANT_ADD(vfio_dma_map_limit_test, _iommu_mode) {		       \

	.iommu_mode = #_iommu_mode,					       \

}



FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES();



#undef FIXTURE_VARIANT_ADD_IOMMU_MODE



FIXTURE_SETUP(vfio_dma_map_limit_test)

{

	struct vfio_dma_region *region = &self->region;

	u64 region_size = getpagesize();



	/*

	 * Over-allocate mmap by double the size to provide enough backing vaddr

	 * for overflow tests

	 */

	self->mmap_size = 2 * region_size;



	self->device = vfio_pci_device_init(device_bdf, variant->iommu_mode);

	region->vaddr = mmap(NULL, self->mmap_size, PROT_READ | PROT_WRITE,

			     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);

	region->size = region_size;

}



FIXTURE_TEARDOWN(vfio_dma_map_limit_test)

{

	vfio_pci_device_cleanup(self->device);

	ASSERT_EQ(munmap(self->region.vaddr, self->mmap_size), 0);

}



TEST_F(vfio_dma_map_limit_test, unmap_range)

{

	struct vfio_dma_region *region = &self->region;

	u64 unmapped;

	int rc;



	vfio_pci_dma_map(self->device, region);

	ASSERT_EQ(region->iova, to_iova(self->device, region->vaddr));



	rc = __vfio_pci_dma_unmap(self->device, region, &unmapped);

	ASSERT_EQ(rc, 0);

	ASSERT_EQ(unmapped, region->size);

}



TEST_F(vfio_dma_map_limit_test, unmap_all)

{

	struct vfio_dma_region *region = &self->region;

	u64 unmapped;

	int rc;



	vfio_pci_dma_map(self->device, region);

	ASSERT_EQ(region->iova, to_iova(self->device, region->vaddr));



	rc = __vfio_pci_dma_unmap_all(self->device, &unmapped);

	ASSERT_EQ(rc, 0);

	ASSERT_EQ(unmapped, region->size);

}



TEST_F(vfio_dma_map_limit_test, overflow)

{

	struct vfio_dma_region *region = &self->region;

	int rc;



	region->size = self->mmap_size;



	rc = __vfio_pci_dma_map(self->device, region);

	ASSERT_EQ(rc, -EOVERFLOW);



	rc = __vfio_pci_dma_unmap(self->device, region, NULL);

	ASSERT_EQ(rc, -EOVERFLOW);

}



int main(int argc, char *argv[])

{

	device_bdf = vfio_selftests_get_bdf(&argc, argv);