linux/tools/testing/selftests/vfio/lib/iommu.c

466 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include <dirent.h>
#include <fcntl.h>
#include <libgen.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/eventfd.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <uapi/linux/types.h>
#include <linux/limits.h>
#include <linux/mman.h>
#include <linux/types.h>
#include <linux/vfio.h>
#include <linux/iommufd.h>
#include "../../../kselftest.h"
#include <libvfio.h>
const char *default_iommu_mode = "iommufd";
/* Reminder: Keep in sync with FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(). */
static const struct iommu_mode iommu_modes[] = {
{
.name = "vfio_type1_iommu",
.container_path = "/dev/vfio/vfio",
.iommu_type = VFIO_TYPE1_IOMMU,
},
{
.name = "vfio_type1v2_iommu",
.container_path = "/dev/vfio/vfio",
.iommu_type = VFIO_TYPE1v2_IOMMU,
},
{
.name = "iommufd_compat_type1",
.container_path = "/dev/iommu",
.iommu_type = VFIO_TYPE1_IOMMU,
},
{
.name = "iommufd_compat_type1v2",
.container_path = "/dev/iommu",
.iommu_type = VFIO_TYPE1v2_IOMMU,
},
{
.name = "iommufd",
},
};
static const struct iommu_mode *lookup_iommu_mode(const char *iommu_mode)
{
int i;
if (!iommu_mode)
iommu_mode = default_iommu_mode;
for (i = 0; i < ARRAY_SIZE(iommu_modes); i++) {
if (strcmp(iommu_mode, iommu_modes[i].name))
continue;
return &iommu_modes[i];
}
VFIO_FAIL("Unrecognized IOMMU mode: %s\n", iommu_mode);
}
int __iommu_hva2iova(struct iommu *iommu, void *vaddr, iova_t *iova)
{
struct dma_region *region;
list_for_each_entry(region, &iommu->dma_regions, link) {
if (vaddr < region->vaddr)
continue;
if (vaddr >= region->vaddr + region->size)
continue;
if (iova)
*iova = region->iova + (vaddr - region->vaddr);
return 0;
}
return -ENOENT;
}
iova_t iommu_hva2iova(struct iommu *iommu, void *vaddr)
{
iova_t iova;
int ret;
ret = __iommu_hva2iova(iommu, vaddr, &iova);
VFIO_ASSERT_EQ(ret, 0, "%p is not mapped into the iommu\n", vaddr);
return iova;
}
static int vfio_iommu_map(struct iommu *iommu, struct dma_region *region)
{
struct vfio_iommu_type1_dma_map args = {
.argsz = sizeof(args),
.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE,
.vaddr = (u64)region->vaddr,
.iova = region->iova,
.size = region->size,
};
if (ioctl(iommu->container_fd, VFIO_IOMMU_MAP_DMA, &args))
return -errno;
return 0;
}
static int iommufd_map(struct iommu *iommu, struct dma_region *region)
{
struct iommu_ioas_map args = {
.size = sizeof(args),
.flags = IOMMU_IOAS_MAP_READABLE |
IOMMU_IOAS_MAP_WRITEABLE |
IOMMU_IOAS_MAP_FIXED_IOVA,
.user_va = (u64)region->vaddr,
.iova = region->iova,
.length = region->size,
.ioas_id = iommu->ioas_id,
};
if (ioctl(iommu->iommufd, IOMMU_IOAS_MAP, &args))
return -errno;
return 0;
}
int __iommu_map(struct iommu *iommu, struct dma_region *region)
{
int ret;
if (iommu->iommufd)
ret = iommufd_map(iommu, region);
else
ret = vfio_iommu_map(iommu, region);
if (ret)
return ret;
list_add(&region->link, &iommu->dma_regions);
return 0;
}
static int __vfio_iommu_unmap(int fd, u64 iova, u64 size, u32 flags, u64 *unmapped)
{
struct vfio_iommu_type1_dma_unmap args = {
.argsz = sizeof(args),
.iova = iova,
.size = size,
.flags = flags,
};
if (ioctl(fd, VFIO_IOMMU_UNMAP_DMA, &args))
return -errno;
if (unmapped)
*unmapped = args.size;
return 0;
}
static int vfio_iommu_unmap(struct iommu *iommu, struct dma_region *region,
u64 *unmapped)
{
return __vfio_iommu_unmap(iommu->container_fd, region->iova,
region->size, 0, unmapped);
}
static int __iommufd_unmap(int fd, u64 iova, u64 length, u32 ioas_id, u64 *unmapped)
{
struct iommu_ioas_unmap args = {
.size = sizeof(args),
.iova = iova,
.length = length,
.ioas_id = ioas_id,
};
if (ioctl(fd, IOMMU_IOAS_UNMAP, &args))
return -errno;
if (unmapped)
*unmapped = args.length;
return 0;
}
static int iommufd_unmap(struct iommu *iommu, struct dma_region *region,
u64 *unmapped)
{
return __iommufd_unmap(iommu->iommufd, region->iova, region->size,
iommu->ioas_id, unmapped);
}
int __iommu_unmap(struct iommu *iommu, struct dma_region *region, u64 *unmapped)
{
int ret;
if (iommu->iommufd)
ret = iommufd_unmap(iommu, region, unmapped);
else
ret = vfio_iommu_unmap(iommu, region, unmapped);
if (ret)
return ret;
list_del_init(&region->link);
return 0;
}
int __iommu_unmap_all(struct iommu *iommu, u64 *unmapped)
{
int ret;
struct dma_region *curr, *next;
if (iommu->iommufd)
ret = __iommufd_unmap(iommu->iommufd, 0, UINT64_MAX,
iommu->ioas_id, unmapped);
else
ret = __vfio_iommu_unmap(iommu->container_fd, 0, 0,
VFIO_DMA_UNMAP_FLAG_ALL, unmapped);
if (ret)
return ret;
list_for_each_entry_safe(curr, next, &iommu->dma_regions, link)
list_del_init(&curr->link);
return 0;
}
static struct vfio_info_cap_header *next_cap_hdr(void *buf, u32 bufsz,
u32 *cap_offset)
{
struct vfio_info_cap_header *hdr;
if (!*cap_offset)
return NULL;
VFIO_ASSERT_LT(*cap_offset, bufsz);
VFIO_ASSERT_GE(bufsz - *cap_offset, sizeof(*hdr));
hdr = (struct vfio_info_cap_header *)((u8 *)buf + *cap_offset);
*cap_offset = hdr->next;
return hdr;
}
static struct vfio_info_cap_header *vfio_iommu_info_cap_hdr(struct vfio_iommu_type1_info *info,
u16 cap_id)
{
struct vfio_info_cap_header *hdr;
u32 cap_offset = info->cap_offset;
u32 max_depth;
u32 depth = 0;
if (!(info->flags & VFIO_IOMMU_INFO_CAPS))
return NULL;
if (cap_offset)
VFIO_ASSERT_GE(cap_offset, sizeof(*info));
max_depth = (info->argsz - sizeof(*info)) / sizeof(*hdr);
while ((hdr = next_cap_hdr(info, info->argsz, &cap_offset))) {
depth++;
VFIO_ASSERT_LE(depth, max_depth, "Capability chain contains a cycle\n");
if (hdr->id == cap_id)
return hdr;
}
return NULL;
}
/* Return buffer including capability chain, if present. Free with free() */
static struct vfio_iommu_type1_info *vfio_iommu_get_info(int container_fd)
{
struct vfio_iommu_type1_info *info;
info = malloc(sizeof(*info));
VFIO_ASSERT_NOT_NULL(info);
*info = (struct vfio_iommu_type1_info) {
.argsz = sizeof(*info),
};
ioctl_assert(container_fd, VFIO_IOMMU_GET_INFO, info);
VFIO_ASSERT_GE(info->argsz, sizeof(*info));
info = realloc(info, info->argsz);
VFIO_ASSERT_NOT_NULL(info);
ioctl_assert(container_fd, VFIO_IOMMU_GET_INFO, info);
VFIO_ASSERT_GE(info->argsz, sizeof(*info));
return info;
}
/*
* Return iova ranges for the device's container. Normalize vfio_iommu_type1 to
* report iommufd's iommu_iova_range. Free with free().
*/
static struct iommu_iova_range *vfio_iommu_iova_ranges(struct iommu *iommu,
u32 *nranges)
{
struct vfio_iommu_type1_info_cap_iova_range *cap_range;
struct vfio_iommu_type1_info *info;
struct vfio_info_cap_header *hdr;
struct iommu_iova_range *ranges = NULL;
info = vfio_iommu_get_info(iommu->container_fd);
hdr = vfio_iommu_info_cap_hdr(info, VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE);
VFIO_ASSERT_NOT_NULL(hdr);
cap_range = container_of(hdr, struct vfio_iommu_type1_info_cap_iova_range, header);
VFIO_ASSERT_GT(cap_range->nr_iovas, 0);
ranges = calloc(cap_range->nr_iovas, sizeof(*ranges));
VFIO_ASSERT_NOT_NULL(ranges);
for (u32 i = 0; i < cap_range->nr_iovas; i++) {
ranges[i] = (struct iommu_iova_range){
.start = cap_range->iova_ranges[i].start,
.last = cap_range->iova_ranges[i].end,
};
}
*nranges = cap_range->nr_iovas;
free(info);
return ranges;
}
/* Return iova ranges of the device's IOAS. Free with free() */
static struct iommu_iova_range *iommufd_iova_ranges(struct iommu *iommu,
u32 *nranges)
{
struct iommu_iova_range *ranges;
int ret;
struct iommu_ioas_iova_ranges query = {
.size = sizeof(query),
.ioas_id = iommu->ioas_id,
};
ret = ioctl(iommu->iommufd, IOMMU_IOAS_IOVA_RANGES, &query);
VFIO_ASSERT_EQ(ret, -1);
VFIO_ASSERT_EQ(errno, EMSGSIZE);
VFIO_ASSERT_GT(query.num_iovas, 0);
ranges = calloc(query.num_iovas, sizeof(*ranges));
VFIO_ASSERT_NOT_NULL(ranges);
query.allowed_iovas = (uintptr_t)ranges;
ioctl_assert(iommu->iommufd, IOMMU_IOAS_IOVA_RANGES, &query);
*nranges = query.num_iovas;
return ranges;
}
static int iova_range_comp(const void *a, const void *b)
{
const struct iommu_iova_range *ra = a, *rb = b;
if (ra->start < rb->start)
return -1;
if (ra->start > rb->start)
return 1;
return 0;
}
/* Return sorted IOVA ranges of the device. Free with free(). */
struct iommu_iova_range *iommu_iova_ranges(struct iommu *iommu, u32 *nranges)
{
struct iommu_iova_range *ranges;
if (iommu->iommufd)
ranges = iommufd_iova_ranges(iommu, nranges);
else
ranges = vfio_iommu_iova_ranges(iommu, nranges);
if (!ranges)
return NULL;
VFIO_ASSERT_GT(*nranges, 0);
/* Sort and check that ranges are sane and non-overlapping */
qsort(ranges, *nranges, sizeof(*ranges), iova_range_comp);
VFIO_ASSERT_LT(ranges[0].start, ranges[0].last);
for (u32 i = 1; i < *nranges; i++) {
VFIO_ASSERT_LT(ranges[i].start, ranges[i].last);
VFIO_ASSERT_LT(ranges[i - 1].last, ranges[i].start);
}
return ranges;
}
static u32 iommufd_ioas_alloc(int iommufd)
{
struct iommu_ioas_alloc args = {
.size = sizeof(args),
};
ioctl_assert(iommufd, IOMMU_IOAS_ALLOC, &args);
return args.out_ioas_id;
}
struct iommu *iommu_init(const char *iommu_mode)
{
const char *container_path;
struct iommu *iommu;
int version;
iommu = calloc(1, sizeof(*iommu));
VFIO_ASSERT_NOT_NULL(iommu);
INIT_LIST_HEAD(&iommu->dma_regions);
iommu->mode = lookup_iommu_mode(iommu_mode);
container_path = iommu->mode->container_path;
if (container_path) {
iommu->container_fd = open(container_path, O_RDWR);
VFIO_ASSERT_GE(iommu->container_fd, 0, "open(%s) failed\n", container_path);
version = ioctl(iommu->container_fd, VFIO_GET_API_VERSION);
VFIO_ASSERT_EQ(version, VFIO_API_VERSION, "Unsupported version: %d\n", version);
} else {
/*
* Require device->iommufd to be >0 so that a simple non-0 check can be
* used to check if iommufd is enabled. In practice open() will never
* return 0 unless stdin is closed.
*/
iommu->iommufd = open("/dev/iommu", O_RDWR);
VFIO_ASSERT_GT(iommu->iommufd, 0);
iommu->ioas_id = iommufd_ioas_alloc(iommu->iommufd);
}
return iommu;
}
void iommu_cleanup(struct iommu *iommu)
{
if (iommu->iommufd)
VFIO_ASSERT_EQ(close(iommu->iommufd), 0);
else
VFIO_ASSERT_EQ(close(iommu->container_fd), 0);
free(iommu);
}