Test IOMMU mapping the BAR mmaps created during vfio_pci_device_setup().
All IOMMU modes are tested: vfio_type1 variants are expected to succeed, while non-type1 modes are expected to fail. iommufd compat mode can be updated to expect success once kernel support lands; native iommufd will not support mapping vaddrs backed by MMIO (it will support dma-buf based MMIO mapping instead).
Signed-off-by: Alex Mastro amastro@fb.com --- tools/testing/selftests/vfio/Makefile | 1 + .../selftests/vfio/vfio_dma_mapping_mmio_test.c | 144 +++++++++++++++++++++ 2 files changed, 145 insertions(+)
diff --git a/tools/testing/selftests/vfio/Makefile b/tools/testing/selftests/vfio/Makefile index 3c796ca99a50..ead27892ab65 100644 --- a/tools/testing/selftests/vfio/Makefile +++ b/tools/testing/selftests/vfio/Makefile @@ -1,5 +1,6 @@ CFLAGS = $(KHDR_INCLUDES) TEST_GEN_PROGS += vfio_dma_mapping_test +TEST_GEN_PROGS += vfio_dma_mapping_mmio_test TEST_GEN_PROGS += vfio_iommufd_setup_test TEST_GEN_PROGS += vfio_pci_device_test TEST_GEN_PROGS += vfio_pci_device_init_perf_test diff --git a/tools/testing/selftests/vfio/vfio_dma_mapping_mmio_test.c b/tools/testing/selftests/vfio/vfio_dma_mapping_mmio_test.c new file mode 100644 index 000000000000..5a86b34329ad --- /dev/null +++ b/tools/testing/selftests/vfio/vfio_dma_mapping_mmio_test.c @@ -0,0 +1,144 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stdio.h> +#include <sys/mman.h> +#include <unistd.h> + +#include <uapi/linux/types.h> +#include <linux/pci_regs.h> +#include <linux/sizes.h> +#include <linux/vfio.h> + +#include <libvfio.h> + +#include "../kselftest_harness.h" + +static const char *device_bdf; + +static struct vfio_pci_bar *largest_mapped_bar(struct vfio_pci_device *device) +{ + u32 flags = VFIO_REGION_INFO_FLAG_READ | VFIO_REGION_INFO_FLAG_WRITE; + struct vfio_pci_bar *largest = NULL; + u64 bar_size = 0; + + for (int i = 0; i < PCI_STD_NUM_BARS; i++) { + struct vfio_pci_bar *bar = &device->bars[i]; + + if (!bar->vaddr) + continue; + + /* + * iommu_map() maps with READ|WRITE, so require the same + * abilities for the underlying VFIO region. + */ + if ((bar->info.flags & flags) != flags) + continue; + + if (bar->info.size > bar_size) { + bar_size = bar->info.size; + largest = bar; + } + } + + return largest; +} + +FIXTURE(vfio_dma_mapping_mmio_test) { + struct iommu *iommu; + struct vfio_pci_device *device; + struct iova_allocator *iova_allocator; + struct vfio_pci_bar *bar; +}; + +FIXTURE_VARIANT(vfio_dma_mapping_mmio_test) { + const char *iommu_mode; +}; + +#define FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode) \ +FIXTURE_VARIANT_ADD(vfio_dma_mapping_mmio_test, _iommu_mode) { \ + .iommu_mode = #_iommu_mode, \ +} + +FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(); + +#undef FIXTURE_VARIANT_ADD_IOMMU_MODE + +FIXTURE_SETUP(vfio_dma_mapping_mmio_test) +{ + self->iommu = iommu_init(variant->iommu_mode); + self->device = vfio_pci_device_init(device_bdf, self->iommu); + self->iova_allocator = iova_allocator_init(self->iommu); + self->bar = largest_mapped_bar(self->device); + + if (!self->bar) + SKIP(return, "No mappable BAR found on device %s", device_bdf); + + if (self->bar->info.size < 2 * getpagesize()) + SKIP(return, "BAR too small (size=0x%llx)", self->bar->info.size); +} + +FIXTURE_TEARDOWN(vfio_dma_mapping_mmio_test) +{ + iova_allocator_cleanup(self->iova_allocator); + vfio_pci_device_cleanup(self->device); + iommu_cleanup(self->iommu); +} + +static void do_mmio_map_test(struct iommu *iommu, + struct iova_allocator *iova_allocator, + void *vaddr, size_t size) +{ + struct dma_region region = { + .vaddr = vaddr, + .size = size, + .iova = iova_allocator_alloc(iova_allocator, size), + }; + + /* + * NOTE: Check for iommufd compat success once it lands. Native iommufd + * will never support this. + */ + if (!strcmp(iommu->mode->name, MODE_VFIO_TYPE1V2_IOMMU) || + !strcmp(iommu->mode->name, MODE_VFIO_TYPE1_IOMMU)) { + iommu_map(iommu, ®ion); + iommu_unmap(iommu, ®ion); + } else { + VFIO_ASSERT_NE(__iommu_map(iommu, ®ion), 0); + VFIO_ASSERT_NE(__iommu_unmap(iommu, ®ion, NULL), 0); + } +} + +TEST_F(vfio_dma_mapping_mmio_test, map_full_bar) +{ + do_mmio_map_test(self->iommu, self->iova_allocator, + self->bar->vaddr, self->bar->info.size); +} + +TEST_F(vfio_dma_mapping_mmio_test, map_partial_bar) +{ + do_mmio_map_test(self->iommu, self->iova_allocator, + self->bar->vaddr, getpagesize()); +} + +/* Test IOMMU mapping of BAR mmap with intentionally poor vaddr alignment. */ +TEST_F(vfio_dma_mapping_mmio_test, map_bar_misaligned) +{ + /* Limit size to bound test time for large BARs */ + size_t size = min_t(size_t, self->bar->info.size, SZ_1G); + size_t page_size = getpagesize(); + void *vaddr; + + vaddr = mmap_aligned(size, SZ_1G, page_size); + vaddr = mmap(vaddr, size, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED, + self->device->fd, self->bar->info.offset); + VFIO_ASSERT_NE(vaddr, MAP_FAILED); + + do_mmio_map_test(self->iommu, self->iova_allocator, vaddr, size); + + VFIO_ASSERT_EQ(munmap(vaddr, size), 0); +} + +int main(int argc, char *argv[]) +{ + device_bdf = vfio_selftests_get_bdf(&argc, argv); + return test_harness_run(argc, argv); +}