vfio: selftests: Add DMA mapping tests for 2M and 1G HugeTLB

Add test coverage of mapping 2M and 1G HugeTLB to vfio_dma_mapping_test
using a fixture variant. If there isn't enough HugeTLB memory available
for the test, just skip them.

Signed-off-by: Josh Hilke <jrhilke@google.com>
[switch from command line option to fixture variant]
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-8-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

1 files changed, 33 insertions, 5 deletions

diff --git a/tools/testing/selftests/vfio/vfio_dma_mapping_test.c b/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
index b56cebbf97eb..8f8e6e9e8197 100644
--- a/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
+++ b/tools/testing/selftests/vfio/vfio_dma_mapping_test.c
@@ -1,8 +1,10 @@
 // SPDX-License-Identifier: GPL-2.0-only
-#include <fcntl.h>
-
+#include <stdio.h>
 #include <sys/mman.h>
+#include <unistd.h>
 
+#include <linux/limits.h>
+#include <linux/mman.h>
 #include <linux/sizes.h>
 #include <linux/vfio.h>
 
@@ -16,6 +18,25 @@ FIXTURE(vfio_dma_mapping_test) {
 	struct vfio_pci_device *device;
 };
 
+FIXTURE_VARIANT(vfio_dma_mapping_test) {
+	u64 size;
+	int mmap_flags;
+};
+
+FIXTURE_VARIANT_ADD(vfio_dma_mapping_test, anonymous) {
+	.mmap_flags = MAP_ANONYMOUS | MAP_PRIVATE,
+};
+
+FIXTURE_VARIANT_ADD(vfio_dma_mapping_test, anonymous_hugetlb_2mb) {
+	.size = SZ_2M,
+	.mmap_flags = MAP_ANONYMOUS | MAP_PRIVATE | MAP_HUGETLB | MAP_HUGE_2MB,
+};
+
+FIXTURE_VARIANT_ADD(vfio_dma_mapping_test, anonymous_hugetlb_1gb) {
+	.size = SZ_1G,
+	.mmap_flags = MAP_ANONYMOUS | MAP_PRIVATE | MAP_HUGETLB | MAP_HUGE_1GB,
+};
+
 FIXTURE_SETUP(vfio_dma_mapping_test)
 {
 	self->device = vfio_pci_device_init(device_bdf, VFIO_TYPE1_IOMMU);
@@ -28,17 +49,24 @@ FIXTURE_TEARDOWN(vfio_dma_mapping_test)
 
 TEST_F(vfio_dma_mapping_test, dma_map_unmap)
 {
-	const u64 size = SZ_2M;
+	const u64 size = variant->size ?: getpagesize();
+	const int flags = variant->mmap_flags;
 	void *mem;
 	u64 iova;
 
-	mem = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
-	ASSERT_NE(mem, MAP_FAILED);
+	mem = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, -1, 0);
+
+	/* Skip the test if there aren't enough HugeTLB pages available. */
+	if (flags & MAP_HUGETLB && mem == MAP_FAILED)
+		SKIP(return, "mmap() failed: %s (%d)\n", strerror(errno), errno);
+	else
+		ASSERT_NE(mem, MAP_FAILED);
 
 	iova = (u64)mem;
 
 	vfio_pci_dma_map(self->device, iova, size, mem);
 	printf("Mapped HVA %p (size 0x%lx) at IOVA 0x%lx\n", mem, size, iova);
+
 	vfio_pci_dma_unmap(self->device, iova, size);
 
 	ASSERT_TRUE(!munmap(mem, size));