#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <unistd.h>
#include <linux/vfio.h>
#include <fcntl.h>void main (int argc, char *argv[]) {int container, group, device, i;struct vfio_group_status group_status ={ .argsz = sizeof(group_status) };struct vfio_iommu_type1_info iommu_info = { .argsz = sizeof(iommu_info) };struct vfio_iommu_type1_dma_map dma_map = { .argsz = sizeof(dma_map) };struct vfio_device_info device_info = { .argsz = sizeof(device_info) };int ret;/* Create a new container */container = open("/dev/vfio/vfio", O_RDWR);if (ioctl(container, VFIO_GET_API_VERSION) != VFIO_API_VERSION) {/* Unknown API version */fprintf(stderr, "unknown api version\n");return;}if (!ioctl(container, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU)) {/* Doesn't support the IOMMU driver we want. */fprintf(stderr, "doesn't support the IOMMU driver we want\n");return;}/* Open the group and get group fd* readlink /sys/bus/pci/devices/0000\:04\:00.0/iommu_group* */group = open("/dev/vfio/14", O_RDWR);if (group == -ENOENT) {fprintf(stderr, "group is not managed by VFIO driver\n");return;}/* Test the group is viable and available */ret = ioctl(group, VFIO_GROUP_GET_STATUS, &group_status);if (ret) {fprintf(stderr, "cannot get VFIO group status, ""error %i (%s)\n", errno, strerror(errno));close(group);return;} else if (!(group_status.flags & VFIO_GROUP_FLAGS_VIABLE)) {fprintf(stderr, "VFIO group is not viable! ""Not all devices in IOMMU group bound to VFIO or unbound\n");close(group);return;}if (!(group_status.flags & VFIO_GROUP_FLAGS_CONTAINER_SET)) {/* Add the group to the container */ret = ioctl(group, VFIO_GROUP_SET_CONTAINER, &container);if (ret) {fprintf(stderr,"cannot add VFIO group to container, error ""%i (%s)\n", errno, strerror(errno));close(group);return;}/* Enable the IOMMU model we want */ret = ioctl(container, VFIO_SET_IOMMU, VFIO_TYPE1_IOMMU);if (!ret) {fprintf(stderr, "using IOMMU type 1\n");} else {fprintf(stderr, "failed to select IOMMU type\n");return;}}/* Get addition IOMMU info */ioctl(container, VFIO_IOMMU_GET_INFO, &iommu_info);/* Allocate some space and setup a DMA mapping */dma_map.vaddr = mmap(0, 1024 * 1024, PROT_READ | PROT_WRITE,MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);dma_map.size = 1024 * 1024;dma_map.iova = 0; /* 1MB starting at 0x0 from device view */dma_map.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE;ioctl(container, VFIO_IOMMU_MAP_DMA, &dma_map);/* Get a file descriptor for the device */device = ioctl(group, VFIO_GROUP_GET_DEVICE_FD, "0000:04:00.0");/* Test and setup the device */ioctl(device, VFIO_DEVICE_GET_INFO, &device_info);for (i = 0; i < device_info.num_regions; i++) {struct vfio_region_info reg = { .argsz = sizeof(reg) };reg.index = i;ioctl(device, VFIO_DEVICE_GET_REGION_INFO, ®);/* Setup mappings... read/write offsets, mmaps* For PCI devices, config space is a region */}for (i = 0; i < device_info.num_irqs; i++) {struct vfio_irq_info irq = { .argsz = sizeof(irq) };irq.index = i;ioctl(device, VFIO_DEVICE_GET_IRQ_INFO, &irq);/* Setup IRQs... eventfds, VFIO_DEVICE_SET_IRQS */}/* Gratuitous device reset and go... */ioctl(device, VFIO_DEVICE_RESET);ioctl(device, VFIO_DEVICE_GET_INFO, &device_info);
}
编译测试
gdb调试demo程序
make
gdb demo
b main
r
查看获取到的PCI设备信息
Breakpoint 1, main (argc=1, argv=0x7fffffffe478) at demo.c:14
14 struct vfio_group_status group_status =
(gdb) bt
#0 main (argc=1, argv=0x7fffffffe478) at demo.c:14
(gdb) list
9 #include <linux/vfio.h>
10 #include <fcntl.h>
11
12 void main (int argc, char *argv[]) {
13 int container, group, device, i;
14 struct vfio_group_status group_status =
15 { .argsz = sizeof(group_status) };
16 struct vfio_iommu_type1_info iommu_info = { .argsz = sizeof(iommu_info) };
17 struct vfio_iommu_type1_dma_map dma_map = { .argsz = sizeof(dma_map) };
18 struct vfio_device_info device_info = { .argsz = sizeof(device_info) };
(gdb) n
16 struct vfio_iommu_type1_info iommu_info = { .argsz = sizeof(iommu_info) };
(gdb) n
17 struct vfio_iommu_type1_dma_map dma_map = { .argsz = sizeof(dma_map) };
(gdb) n
18 struct vfio_device_info device_info = { .argsz = sizeof(device_info) };
(gdb) n
22 container = open("/dev/vfio/vfio", O_RDWR);
(gdb) n
24 if (ioctl(container, VFIO_GET_API_VERSION) != VFIO_API_VERSION) {
(gdb) n
30 if (!ioctl(container, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU)) {
(gdb) n
39 group = open("/dev/vfio/14", O_RDWR);
(gdb) n
41 if (group == -ENOENT) {
(gdb) p group
$1 = 8
(gdb) n
47 ret = ioctl(group, VFIO_GROUP_GET_STATUS, &group_status);
(gdb) n
48 if (ret) {
(gdb) p ret
$2 = 0
(gdb) p group_status
$3 = {argsz = 8, flags = 1}
(gdb) n
53 } else if (!(group_status.flags & VFIO_GROUP_FLAGS_VIABLE)) {
(gdb) n
60 if (!(group_status.flags & VFIO_GROUP_FLAGS_CONTAINER_SET)) {
(gdb) n
62 ret = ioctl(group, VFIO_GROUP_SET_CONTAINER, &container);
(gdb) p container
$4 = 7
(gdb) n
63 if (ret) {
(gdb) p ret
$5 = 0
(gdb) n
72 ret = ioctl(container, VFIO_SET_IOMMU, VFIO_TYPE1_IOMMU);
(gdb) n
73 if (!ret) {
(gdb) n
74 fprintf(stderr, "using IOMMU type 1\n");
(gdb) n
using IOMMU type 1
82 ioctl(container, VFIO_IOMMU_GET_INFO, &iommu_info);
(gdb) n
85 dma_map.vaddr = mmap(0, 1024 * 1024, PROT_READ | PROT_WRITE,
(gdb) p iommu_info
$6 = {argsz = 116, flags = 3, iova_pgsizes = 4096, cap_offset = 0}
(gdb) n
87 dma_map.size = 1024 * 1024;
(gdb) n
88 dma_map.iova = 0; /* 1MB starting at 0x0 from device view */
(gdb) n
89 dma_map.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE;
(gdb) n
91 ioctl(container, VFIO_IOMMU_MAP_DMA, &dma_map);
(gdb) n
94 device = ioctl(group, VFIO_GROUP_GET_DEVICE_FD, "0000:04:00.0");
(gdb) n
97 ioctl(device, VFIO_DEVICE_GET_INFO, &device_info);
(gdb) p device
$7 = 9
(gdb) n
99 for (i = 0; i < device_info.num_regions; i++) {
(gdb) p device_info
$8 = {argsz = 20, flags = 2, num_regions = 9, num_irqs = 5, cap_offset = 0}
