On 2026-07-02 11:28 PM, Narayana Murty N wrote:
> Prepare the DMA window before IOVA allocation in the DMA mapping tests.
>
> Anonymous mappings use the default sPAPR DMA window. HugeTLB mappings force
> a DDW with the requested page size, allowing the test to exercise DDW
> creation, mapping, unmapping, and cleanup.
>
> Skip gracefully when hugepage allocation fails or when the platform does
> not support the requested DDW characteristics. Also skip unmap-all when
> the backend cannot pair it with the sPAPR memory unregister flow.
>
> Signed-off-by: Narayana Murty N <[email protected]>
> ---
> .../selftests/vfio/vfio_dma_mapping_test.c | 22 +++++++++++++++++++
> 1 file changed, 22 insertions(+)
>
> diff --git a/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
> b/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
> index 7d0de8c79de1..4411fdbd56da 100644
> --- a/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
> +++ b/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
> @@ -1,5 +1,6 @@
> // SPDX-License-Identifier: GPL-2.0-only
> #include <stdio.h>
> +#include <string.h>
> #include <sys/mman.h>
> #include <unistd.h>
>
> @@ -119,8 +120,19 @@
> FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(anonymous_hugetlb_1gb, SZ_1G, MAP_HUGETLB
> |
>
> FIXTURE_SETUP(vfio_dma_mapping_test)
> {
> + const u64 page_size = variant->size ?: getpagesize();
> + const bool force_dynamic = !!variant->size;
This is kind of arbitrary right? Should we add explicit variants for
dynamic/default windows (see below). But we need some way to skip the dynamic
window tests on non-spapr iommus...
diff --git a/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
b/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
index cd2d3276a46c..b54c529ebedb 100644
--- a/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
+++ b/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
@@ -103,15 +103,21 @@ FIXTURE_VARIANT(vfio_dma_mapping_test) {
const char *iommu_mode;
u64 size;
int mmap_flags;
+ bool dynamic_window;
};
-#define FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode, _name, _size, _mmap_flags)
\
-FIXTURE_VARIANT_ADD(vfio_dma_mapping_test, _iommu_mode ## _ ## _name) {
\
- .iommu_mode = #_iommu_mode, \
- .size = (_size), \
- .mmap_flags = MAP_ANONYMOUS | MAP_PRIVATE | (_mmap_flags), \
+#define __FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode, _name, _size,
_mmap_flags, _dynamic_window) \
+FIXTURE_VARIANT_ADD(vfio_dma_mapping_test,_iommu_mode ## _ ## _name) { \
+ .iommu_mode = #_iommu_mode,
\
+ .size = (_size),
\
+ .mmap_flags = MAP_ANONYMOUS | MAP_PRIVATE | (_mmap_flags),
\
+ .dynamic_window = _dynamic_window,
\
}
+#define FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode, _name, _size, _mmap_flags)
\
+__FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode, _name, _size, _mmap_flags,
false); \
+__FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode, _name ## _dynamic_window, _size,
_mmap_flags, true) \
+
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);
@@ -121,14 +127,13 @@
FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(anonymous_hugetlb_1gb, SZ_1G, MAP_HUGETLB |
FIXTURE_SETUP(vfio_dma_mapping_test)
{
const u64 page_size = variant->size ?: getpagesize();
- const bool force_dynamic = !!variant->size;
int ret;
self->iommu = iommu_init(variant->iommu_mode);
self->device = vfio_pci_device_init(device_bdf, self->iommu);
ret = iommu_prepare_dma_window(self->iommu, page_size, page_size,
- force_dynamic);
+ variant->dynamic_window);
if (ret)
SKIP(return, "DMA window unavailable: %s (%d)\n",
strerror(-ret), -ret);
> + int ret;
> +
> self->iommu = iommu_init(variant->iommu_mode);
> self->device = vfio_pci_device_init(device_bdf, self->iommu);
> +
> + ret = iommu_prepare_dma_window(self->iommu, page_size, page_size,
> + force_dynamic);
> + if (ret)
> + SKIP(return, "DMA window unavailable: %s (%d)\n",
> + strerror(-ret), -ret);
> +
> self->iova_allocator = iova_allocator_init(self->iommu);
> }
>
> @@ -227,6 +239,7 @@ FIXTURE_SETUP(vfio_dma_map_limit_test)
> u64 region_size = getpagesize();
> iova_t last_iova;
> u32 nranges;
> + int ret;
>
> /*
> * Over-allocate mmap by double the size to provide enough backing vaddr
> @@ -236,6 +249,13 @@ FIXTURE_SETUP(vfio_dma_map_limit_test)
>
> self->iommu = iommu_init(variant->iommu_mode);
> self->device = vfio_pci_device_init(device_bdf, self->iommu);
> +
> + ret = iommu_prepare_dma_window(self->iommu, region_size, region_size,
> + false);
> + if (ret)
> + SKIP(return, "DMA window unavailable: %s (%d)\n",
> + strerror(-ret), -ret);
> +
> region->vaddr = mmap(NULL, self->mmap_size, PROT_READ | PROT_WRITE,
> MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> ASSERT_NE(region->vaddr, MAP_FAILED);
> @@ -277,6 +297,8 @@ TEST_F(vfio_dma_map_limit_test, unmap_all)
> u64 unmapped;
> int rc;
>
> + if (!iommu_supports_unmap_all(self->iommu))
> + SKIP(return, "IOMMU backend does not support unmap-all\n");
> iommu_map(self->iommu, region);
> ASSERT_EQ(region->iova, to_iova(self->device, region->vaddr));
>
> --
> 2.51.1
>
