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/*
* Userspace mediated device sample application
*
* Copyright (c) 2019, Nutanix Inc. All rights reserved.
* Author: Thanos Makatos <thanos@nutanix.com>
* Swapnil Ingle <swapnil.ingle@nutanix.com>
* Felipe Franciosi <felipe@nutanix.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Nutanix nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <stdbool.h>
#include <string.h>
#include <linux/vfio.h>
#include <limits.h>
#include <assert.h>
#include <sys/ioctl.h>
#include <inttypes.h>
#define VFIO_PATH "/dev/vfio/"
#define VFIO_CTR_PATH VFIO_PATH "vfio"
#define SYSFS_PCI_DEV_PATH "/sys/bus/pci/devices/"
#define SYSFS_IOMMU_GROUP "/iommu_group"
static int
pci_group_id(const char *bdf)
{
char *dev_path;
char group_path[PATH_MAX];
int group_id;
assert(bdf);
asprintf(&dev_path, SYSFS_PCI_DEV_PATH "%s" SYSFS_IOMMU_GROUP, bdf);
memset(group_path, 0, sizeof(group_path));
readlink(dev_path, group_path, sizeof(group_path));
free(dev_path);
sscanf(basename(group_path), "%d", &group_id);
return group_id;
}
static inline void*
test_map_dma(const int fd, const unsigned long size, const unsigned long iova)
{
int err;
struct vfio_iommu_type1_dma_map dma_map = {
.argsz = sizeof(dma_map),
.size = size,
.iova = iova,
.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE,
};
/* Allocate some space and setup a DMA mapping */
/* FIXME it *must* be MAP_SHARED */
dma_map.vaddr = (unsigned long long)mmap(0, size, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS, 0, 0);
if (dma_map.vaddr == (unsigned long)MAP_FAILED) {
perror("failed to map DMA");
return NULL;
}
printf("%llx\n", dma_map.vaddr);
strcpy((char*)dma_map.vaddr, "foo");
fprintf(stderr, "attempting to MAP_DMA IOVA=%llx\n", dma_map.iova);
err = ioctl(fd, VFIO_IOMMU_MAP_DMA, &dma_map);
if (err) {
fprintf(stderr, "failed to MAP_DMA: %d (errno=%d)", err, errno);
return NULL;
}
printf("[%s]\n", (char*)dma_map.vaddr);
return (void*)dma_map.vaddr;
}
static inline void
test_unmap_dma(const int fd, const unsigned long size, const unsigned long iova)
{
int err;
struct vfio_iommu_type1_dma_unmap dma_unmap = {
.argsz = sizeof dma_unmap,
.size = size,
.iova = iova,
.flags = 0
};
err = ioctl(fd, VFIO_IOMMU_UNMAP_DMA, &dma_unmap);
if (err) {
perror("UNMAP_DMA\n");
return;
}
printf("unmapped IOVA=%llx\n", dma_unmap.iova);
}
int main(int argc, char * argv[])
{
int err, vfio_ctr_fd, vfio_grp_fd, vfio_dev_fd;
char *grp_path;
#ifdef DEBUG
struct vfio_group_status grp_status;
#endif
struct vfio_iommu_type1_info iommu_info;
void *dma_map_addr = NULL;
if (argc != 2) {
printf("Usage: %s <device bdf in full>\n", argv[0]);
printf(" ex: %s 0000:82:00.0\n", argv[0]);
return EXIT_FAILURE;
}
vfio_ctr_fd = open(VFIO_CTR_PATH, O_RDWR);
assert(vfio_ctr_fd >= 0);
#ifdef DEBUG
err = ioctl(vfio_ctr_fd, VFIO_GET_API_VERSION);
assert(err == VFIO_API_VERSION);
err = ioctl(vfio_ctr_fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU);
assert(err == 1);
#endif
// Open the VFIO entry for this device's IOMMU GROUP.
err = asprintf(&grp_path, VFIO_PATH "%d", pci_group_id(argv[1]));
assert(err > 0);
vfio_grp_fd = open(grp_path, O_RDWR);
assert(vfio_grp_fd >= 0);
free(grp_path);
#ifdef DEBUG
// Ensure group is viable.
memset(&grp_status, 0, sizeof(grp_status));
grp_status.argsz = sizeof(grp_status);
err = ioctl(vfio_grp_fd, VFIO_GROUP_GET_STATUS, &grp_status);
assert(!err);
assert((grp_status.flags & VFIO_GROUP_FLAGS_VIABLE) == 1);
#endif
// Add the group to the container.
err = ioctl(vfio_grp_fd, VFIO_GROUP_SET_CONTAINER, &vfio_ctr_fd);
assert(!err);
// Enable IOMMU type 1 on container.
err = ioctl(vfio_ctr_fd, VFIO_SET_IOMMU, VFIO_TYPE1v2_IOMMU);
assert(!err);
// Fetch IOMMU information from VFIO.
memset(&iommu_info, 0, sizeof(iommu_info));
iommu_info.argsz = sizeof(iommu_info);
err = ioctl(vfio_ctr_fd, VFIO_IOMMU_GET_INFO, &iommu_info);
assert(!err);
// Get a device fd from VFIO.
vfio_dev_fd = ioctl(vfio_grp_fd, VFIO_GROUP_GET_DEVICE_FD, argv[1]);
assert(vfio_dev_fd >= 0);
void *p;
p = mmap(NULL, sysconf(_SC_PAGESIZE), PROT_READ | PROT_WRITE,
MAP_SHARED, vfio_dev_fd, 0);
assert(p != MAP_FAILED);
printf("%p\n", p);
printf("%s\n", (char*)p);
dma_map_addr = test_map_dma(vfio_ctr_fd, 4096, 0xdeadbeef000);
if (!dma_map_addr)
exit(EXIT_FAILURE);
test_unmap_dma(vfio_ctr_fd, 4096, 0xdeadbeef000);
return 0;
}
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