1 files changed, 161 insertions, 0 deletions
diff --git a/vfio-iommu-map-unmap.c b/vfio-iommu-map-unmap.c
new file mode 100644
index 0000000..a5d5c46
--- /dev/null
+++ b/vfio-iommu-map-unmap.c
@@ -0,0 +1,161 @@
+#include <errno.h>
+#include <libgen.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <linux/ioctl.h>
+#include <linux/vfio.h>
+
+#define MAP_SIZE (1UL * 1024 * 1024 * 1024)
+#define MAP_CHUNK (4 * 1024)
+#define REALLOC_INTERVAL 30
+
+void usage(char *name)
+{
+	printf("usage: %s <group id> <allocs> \n", name);
+}
+
+int main(int argc, char **argv)
+{
+	int ret, container, group;
+	char path[64];
+	unsigned long i, count, max;
+	void **maps;
+	struct vfio_group_status group_status = {
+		.argsz = sizeof(group_status)
+	};
+	struct vfio_iommu_type1_dma_map dma_map = {
+		.argsz = sizeof(dma_map)
+	};
+	struct vfio_iommu_type1_dma_unmap dma_unmap = {
+		.argsz = sizeof(dma_unmap)
+	};
+
+	if (argc != 3) {
+		usage(argv[0]);
+		return -1;
+	}
+
+	container = open("/dev/vfio/vfio", O_RDWR);
+	if (container < 0) {
+		printf("Failed to open /dev/vfio/vfio, %d (%s)\n",
+		       container, strerror(errno));
+		return container;
+	}
+
+	snprintf(path, sizeof(path), "/dev/vfio/%d", atoi(argv[1]));
+	group = open(path, O_RDWR);
+	if (group < 0) {
+		printf("Failed to open %s, %d (%s)\n",
+		       path, group, strerror(errno));
+		return group;
+	}
+	max = atoi(argv[2]);
+
+	ret = ioctl(group, VFIO_GROUP_GET_STATUS, &group_status);
+	if (ret) {
+		printf("ioctl(VFIO_GROUP_GET_STATUS) failed\n");
+		return ret;
+	}
+
+	if (!(group_status.flags & VFIO_GROUP_FLAGS_VIABLE)) {
+		printf("Group not viable, are all devices attached to vfio?\n");
+		return -1;
+	}
+
+	ret = ioctl(group, VFIO_GROUP_SET_CONTAINER, &container);
+	if (ret) {
+		printf("Failed to set group container\n");
+		return ret;
+	}
+
+	ret = ioctl(container, VFIO_SET_IOMMU, VFIO_TYPE1_IOMMU);
+	if (ret) {
+		printf("Failed to set IOMMU\n");
+		return ret;
+	}
+
+	/* Test code */
+	dma_map.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE;
+	dma_map.size = MAP_CHUNK;
+	dma_unmap.size = MAP_SIZE;
+	dma_unmap.iova = 0;
+
+	/* Track our mmaps for re-use */
+	maps = malloc(sizeof(void *) * (MAP_SIZE/dma_map.size));
+	if (!maps) {
+		printf("Failed to allocate map (%s)\n", strerror(errno));
+		return -1;
+	}
+
+	memset(maps, 0, sizeof(void *) * (MAP_SIZE/dma_map.size));
+
+	for (count = 0; count < max; count++) {
+
+		/* Every REALLOC_INTERVAL, dump our mappings to give THP something to collapse */
+		if (count % REALLOC_INTERVAL == 0) {
+			for (i = 0; i < MAP_SIZE/dma_map.size; i++) {
+				if (maps[i]) {
+					munmap(maps[i], dma_map.size);
+					maps[i] = NULL;
+				}
+			}
+			if (count) {
+				printf("\t%ld\n", count);
+				//return 0;
+			}
+			printf("|");
+			fflush(stdout);
+		}
+
+		/* Map MAP_CHUNK at a time, each chunk is pinned on map, so THP can't do anything until unmap */
+		for (i = dma_map.iova = 0; i < MAP_SIZE/dma_map.size; i++, dma_map.iova += dma_map.size) {
+			if (!maps[i]) {
+				maps[i] = mmap(NULL, dma_map.size,
+						PROT_READ | PROT_WRITE,
+						MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+				if (maps[i] == MAP_FAILED) {
+					printf("Failed to mmap memory (%s)\n", strerror(errno));
+					return -1;
+				}
+			}
+
+			ret = madvise(maps[i], dma_map.size, MADV_HUGEPAGE);
+			if (ret) {
+				printf("Madvise failed (%s)\n", strerror(errno));
+			}
+
+			dma_map.vaddr = (unsigned long)maps[i];
+
+			ret = ioctl(container, VFIO_IOMMU_MAP_DMA, &dma_map);
+			if (ret) {
+				printf("Failed to map memory (%s)\n",
+					strerror(errno));
+				return ret;
+			}
+		}
+
+		printf("+");
+		fflush(stdout);
+
+		/* Unmap everything at once */
+		ret = ioctl(container, VFIO_IOMMU_UNMAP_DMA, &dma_unmap);
+		if (ret) {
+			printf("Failed to unmap memory (%s)\n", strerror(errno));
+			return ret;
+		}
+
+		printf("-");
+		fflush(stdout);
+	}
+	printf("\n");
+
+	return 0;
+}