This test exercises VFIO DMABUF mmap() to userspace, including various revocation/shutdown cases (which make the VMA inacessible).
This is a TEMPORARY test, just to illustrate a new UAPI and DMABUF/mmap() usage. Since it originates from out-of-tree code, it duplicates some of the VFIO device setup code in .../selftests/vfio/lib. Instead, the tests should be folded into the existing VFIO tests.
Signed-off-by: Matt Evans mattev@meta.com --- tools/testing/selftests/vfio/Makefile | 1 + .../vfio/standalone/vfio_dmabuf_mmap_test.c | 837 ++++++++++++++++++ 2 files changed, 838 insertions(+) create mode 100644 tools/testing/selftests/vfio/standalone/vfio_dmabuf_mmap_test.c
diff --git a/tools/testing/selftests/vfio/Makefile b/tools/testing/selftests/vfio/Makefile index 8e90e409e91d..8679d96e5b92 100644 --- a/tools/testing/selftests/vfio/Makefile +++ b/tools/testing/selftests/vfio/Makefile @@ -12,6 +12,7 @@ TEST_GEN_PROGS += vfio_iommufd_setup_test TEST_GEN_PROGS += vfio_pci_device_test TEST_GEN_PROGS += vfio_pci_device_init_perf_test TEST_GEN_PROGS += vfio_pci_driver_test +TEST_GEN_PROGS += standalone/vfio_dmabuf_mmap_test
TEST_FILES += scripts/cleanup.sh TEST_FILES += scripts/lib.sh diff --git a/tools/testing/selftests/vfio/standalone/vfio_dmabuf_mmap_test.c b/tools/testing/selftests/vfio/standalone/vfio_dmabuf_mmap_test.c new file mode 100644 index 000000000000..0c087497b777 --- /dev/null +++ b/tools/testing/selftests/vfio/standalone/vfio_dmabuf_mmap_test.c @@ -0,0 +1,837 @@ +/* + * Tests for VFIO DMABUF userspace mmap() + * + * As well as the basics (mmap() a BAR resource to userspace), test + * shutdown/unmapping, aliasing, and DMABUF revocation scenarios. + * + * This test relies on being attached to a QEMU EDU device (for a + * simple known MMIO layout). Example invocation, assuming function + * 0000:00:03.0 is the target: + * + * # lspci -n -s 00:03.0 + * 00:03.0 00ff: 1234:11e8 (rev 10) + * + * # readlink /sys/bus/pci/devices/0000:00:03.0/iommu_group + * ../../../../../kernel/iommu_groups/3 + * + * (if there's a driver already attached) + * # echo 0000:00:03.0 > /sys/bus/pci/devices/0000:00:03.0/driver/unbind + * + * (and, might need) + * # echo 1 > /sys/module/vfio_iommu_type1/parameters/allow_unsafe_interrupts + * + * Attach to VFIO: + * # echo 1234 11e8 > /sys/bus/pci/drivers/vfio-pci/new_id + * + * There should be only one thing in the group: + * # ls /sys/bus/pci/devices/0000:00:03.0/iommu_group/devices + * + * Then given above an invocation would be: + * # this_test -r 0000:00:03.0 -g 3 + * + * However, note the QEMU EDU device has a very small address span of + * useful things in BAR0, which makes testing a non-zero BAR offset + * impossible. An "extended EDU" device is supported, which just + * presents a large chunk of memory as a second BAR resource: this + * allows non-zero BAR offsets to be tested. See below for a QEMU + * diff... + * + * Copyright (c) Meta Platforms, Inc. and affiliates. + * + * This software may be used and distributed according to the terms of the + * GNU General Public License version 2. + */ + +/* +diff --git a/hw/misc/edu.c b/hw/misc/edu.c +index cece633e11..5f119e0642 100644 +--- a/hw/misc/edu.c ++++ b/hw/misc/edu.c +@@ -47,6 +47,7 @@ DECLARE_INSTANCE_CHECKER(EduState, EDU, + struct EduState { + PCIDevice pdev; + MemoryRegion mmio; ++ MemoryRegion ram; + + QemuThread thread; + QemuMutex thr_mutex; +@@ -386,7 +387,12 @@ static void pci_edu_realize(PCIDevice *pdev, Error **errp) + + memory_region_init_io(&edu->mmio, OBJECT(edu), &edu_mmio_ops, edu, + "edu-mmio", 1 * MiB); ++ memory_region_init_ram(&edu->ram, OBJECT(edu), "edu-ram", 64 * MiB, &error_fatal); + pci_register_bar(pdev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &edu->mmio); ++ pci_register_bar(pdev, 1, ++ PCI_BASE_ADDRESS_SPACE_MEMORY | ++ PCI_BASE_ADDRESS_MEM_PREFETCH | ++ PCI_BASE_ADDRESS_MEM_TYPE_64, &edu->ram); + } + + static void pci_edu_uninit(PCIDevice *pdev) +*/ + +#include <errno.h> +#include <inttypes.h> +#include <fcntl.h> +#include <limits.h> +#include <linux/dma-buf.h> +#include <linux/vfio.h> +#include <setjmp.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> + +#define ROUND_UP(x, to) (((x) + (to) - 1) & ~((to) - 1)) +#define MiB(x) ((x) * 1024ULL * 1024) + +#define EDU_REG_MAGIC 0x00 +#define EDU_MAGIC_VAL 0x010000edu +#define EDU_REG_INVERT 0x04 + +#define FAIL_IF(cond, msg...) \ + do { \ + if (cond) { \ + printf("\n\nFAIL:\t"); \ + printf(msg); \ + exit(1); \ + } \ + } while (0) + +static int vfio_setup(int groupnr, char *rid_str, + struct vfio_region_info *out_mappable_regions, + int nr_regions, int *out_nr_regions, int *out_vfio_cfd, + int *out_vfio_devfd) +{ + /* Create a new container, add group to it, open device, read + * resource, reset, etc. Based on the example code in + * Documentation/driver-api/vfio.rst + */ + + int container = open("/dev/vfio/vfio", O_RDWR); + + int r = ioctl(container, VFIO_GET_API_VERSION); + + if (r != VFIO_API_VERSION) { + /* Unknown API version */ + printf("-E- Unknown API ver %d\n", r); + return 1; + } + + if (ioctl(container, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU) != 1) { + printf("-E- Doesn't support type 1\n"); + return 1; + } + + char devpath[PATH_MAX]; + + snprintf(devpath, PATH_MAX - 1, "/dev/vfio/%d", groupnr); + /* Open the group */ + int group = open(devpath, O_RDWR); + + if (group < 0) { + printf("-E- Can't open VFIO device (group %d)\n", groupnr); + return 1; + } + + /* Test the group is viable and available */ + struct vfio_group_status group_status = { .argsz = sizeof( + group_status) }; + + if (ioctl(group, VFIO_GROUP_GET_STATUS, &group_status)) { + perror("-E- Can't get group status"); + return 1; + } + + if (!(group_status.flags & VFIO_GROUP_FLAGS_VIABLE)) { + /* Group is not viable (ie, not all devices bound for vfio) */ + printf("-E- Group %d is not viable!\n", groupnr); + return 1; + } + + /* Add the group to the container */ + if (ioctl(group, VFIO_GROUP_SET_CONTAINER, &container)) { + perror("-E- Can't add group to container"); + return 1; + } + + /* Enable the IOMMU model we want */ + if (ioctl(container, VFIO_SET_IOMMU, VFIO_TYPE1_IOMMU)) { + perror("-E- Can't select T1"); + return 1; + } + + /* Get addition IOMMU info */ + struct vfio_iommu_type1_info iommu_info = { .argsz = sizeof( + iommu_info) }; + + if (ioctl(container, VFIO_IOMMU_GET_INFO, &iommu_info)) { + perror("-E- Can't get VFIO info"); + return 1; + } + + /* Get a file descriptor for the device */ + int device = ioctl(group, VFIO_GROUP_GET_DEVICE_FD, rid_str); + + if (device < 0) { + perror("-E- Can't get device fd"); + return 1; + } + close(group); + + /* Test and setup the device */ + struct vfio_device_info device_info = { .argsz = sizeof(device_info) }; + + if (ioctl(device, VFIO_DEVICE_GET_INFO, &device_info)) { + perror("-E- Can't get device info"); + return 1; + } + printf("-i- %d device regions, flags 0x%x\n", device_info.num_regions, + device_info.flags); + + /* Regions are BAR0-5 then ROM, config, VGA */ + int out_region = 0; + + for (int i = 0; i < device_info.num_regions; i++) { + struct vfio_region_info reg = { .argsz = sizeof(reg) }; + + reg.index = i; + + if (ioctl(device, VFIO_DEVICE_GET_REGION_INFO, ®)) { + /* We expect EINVAL if there's no VGA region */ + printf("-W- Region %d: ERROR %d\n", i, errno); + } else { + printf("-i- Region %d: flags 0x%08x (%c%c%c), cap_offs %d, size 0x%llx, offs 0x%llx\n", + i, reg.flags, + (reg.flags & VFIO_REGION_INFO_FLAG_READ) ? 'R' : + '-', + (reg.flags & VFIO_REGION_INFO_FLAG_WRITE) ? 'W' : + '-', + (reg.flags & VFIO_REGION_INFO_FLAG_MMAP) ? 'M' : + '-', + reg.cap_offset, reg.size, reg.offset); + + if ((reg.flags & VFIO_REGION_INFO_FLAG_MMAP) && + (out_region < nr_regions)) + out_mappable_regions[out_region++] = reg; + } + } + *out_nr_regions = out_region; + +#ifdef THERE_ARE_NO_IRQS_YET + 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 */ + } +#endif + /* Gratuitous device reset and go... */ + if (ioctl(device, VFIO_DEVICE_RESET)) + perror("-W- Can't reset device (continuing)"); + + *out_vfio_cfd = container; + *out_vfio_devfd = device; + + return 0; +} + +static int vfio_feature_present(int dev_fd, uint32_t feature) +{ + struct vfio_device_feature probeftr = { + .argsz = sizeof(probeftr), + .flags = VFIO_DEVICE_FEATURE_PROBE | VFIO_DEVICE_FEATURE_GET | + feature, + }; + return ioctl(dev_fd, VFIO_DEVICE_FEATURE, &probeftr) == 0; +} + +static int vfio_create_dmabuf(int dev_fd, uint32_t region, uint64_t offset, + uint64_t length) +{ + uint64_t ftrbuf + [ROUND_UP(sizeof(struct vfio_device_feature) + + sizeof(struct vfio_device_feature_dma_buf) + + sizeof(struct vfio_region_dma_range), + 8) / + 8]; + + struct vfio_device_feature *f = (struct vfio_device_feature *)ftrbuf; + struct vfio_device_feature_dma_buf *db = + (struct vfio_device_feature_dma_buf *)f->data; + struct vfio_region_dma_range *range = + (struct vfio_region_dma_range *)db->dma_ranges; + + f->argsz = sizeof(ftrbuf); + f->flags = VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_DMA_BUF; + db->region_index = region; + db->open_flags = O_RDWR | O_CLOEXEC; + db->flags = 0; + db->nr_ranges = 1; + range->offset = offset; + range->length = length; + + return ioctl(dev_fd, VFIO_DEVICE_FEATURE, &ftrbuf); +} + +/* As above, but try multiple ranges in one dmabuf */ +static int vfio_create_dmabuf_dual(int dev_fd, uint32_t region, + uint64_t offset0, uint64_t length0, + uint64_t offset1, uint64_t length1) +{ + uint64_t ftrbuf + [ROUND_UP(sizeof(struct vfio_device_feature) + + sizeof(struct vfio_device_feature_dma_buf) + + (sizeof(struct vfio_region_dma_range) * 2), + 8) / + 8]; + + struct vfio_device_feature *f = (struct vfio_device_feature *)ftrbuf; + struct vfio_device_feature_dma_buf *db = + (struct vfio_device_feature_dma_buf *)f->data; + struct vfio_region_dma_range *range = + (struct vfio_region_dma_range *)db->dma_ranges; + + f->argsz = sizeof(ftrbuf); + f->flags = VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_DMA_BUF; + db->region_index = region; + db->open_flags = O_RDWR | O_CLOEXEC; + db->flags = 0; + db->nr_ranges = 2; + range[0].offset = offset0; + range[0].length = length0; + range[1].offset = offset1; + range[1].length = length1; + + return ioctl(dev_fd, VFIO_DEVICE_FEATURE, &ftrbuf); +} + +static volatile uint32_t *mmap_resource_aligned(size_t size, + unsigned long align, int fd, + unsigned long offset) +{ + void *v; + + if (align <= getpagesize()) { + v = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, + offset); + FAIL_IF(v == MAP_FAILED, + "Can't mmap fd %d (size 0x%lx, offset 0x%lx), %d\n", fd, + size, offset, errno); + } else { + size_t resv_size = size + align; + void *resv = + mmap(0, resv_size, 0, MAP_PRIVATE | MAP_ANON, -1, 0); + FAIL_IF(resv == MAP_FAILED, + "Can't mmap reservation, size 0x%lx, %d\n", resv_size, + errno); + + uintptr_t pos = ((uintptr_t)resv + (align - 1)) & ~(align - 1); + + v = mmap((void *)pos, size, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_FIXED, fd, offset); + FAIL_IF(v == MAP_FAILED, + "Can't mmap-fixed fd %d (size 0x%lx, offset 0x%lx), %d\n", + fd, size, offset, errno); + madvise((void *)v, size, MADV_HUGEPAGE); + + /* Tidy */ + if (pos > (uintptr_t)resv) + munmap(resv, pos - (uintptr_t)resv); + if (pos + size < (uintptr_t)resv + resv_size) + munmap((void *)pos + size, + (uintptr_t)resv + resv_size - (pos + size)); + } + + return (volatile uint32_t *)v; +} + +static volatile uint32_t *mmap_resource(size_t size, int fd, + unsigned long offset) +{ + return mmap_resource_aligned(size, getpagesize(), fd, offset); +} + +static void check_mmio(volatile uint32_t *base) +{ + static uint32_t magic = 0xdeadbeef; + uint32_t v; + + printf("-i- MMIO check: "); + + /* Trivial MMIO */ + v = base[EDU_REG_MAGIC / 4]; + FAIL_IF(v != EDU_MAGIC_VAL, + "Magic value %08x incorrect, BAR map bad?\n", v); + + base[EDU_REG_INVERT / 4] = magic; + v = base[EDU_REG_INVERT / 4]; + FAIL_IF(v != ~magic, "Inverterizer value %08x bad (should be %08x)\n", + v, ~magic); + printf("OK\n"); + + magic = (magic << 1) ^ (magic >> 1) ^ (magic << 7); +} + +static int revoke_dmabuf(int dev_fd, int dmabuf_fd) +{ + struct vfio_pci_dmabuf_revoke dmabuf_rev = { + .argsz = sizeof(dmabuf_rev), + .dmabuf_fd = dmabuf_fd, + }; + return ioctl(dev_fd, VFIO_DEVICE_PCI_DMABUF_REVOKE, &dmabuf_rev); +} + +static jmp_buf jmpbuf; + +static void sighandler(int sig) +{ + printf("*** Signal %d ***\n", sig); + siglongjmp(jmpbuf, sig); +} + +static void setup_signals(void) +{ + struct sigaction sa = { + .sa_handler = sighandler, + .sa_flags = 0, + }; + + sigaction(SIGBUS, &sa, NULL); +} + +static int vfio_dmabuf_test(int groupnr, char *rid_str) +{ + /* Only expecting one or two regions */ + struct vfio_region_info bar_region[2]; + int num_regions = 0; + int container_fd, dev_fd; + int r = vfio_setup(groupnr, rid_str, &bar_region[0], 2, &num_regions, + &container_fd, &dev_fd); + + FAIL_IF(r, "VFIO setup failed\n"); + FAIL_IF(!vfio_feature_present(dev_fd, VFIO_DEVICE_FEATURE_DMA_BUF), + "VFIO DMABUF support not available\n"); + + printf("-i- Container fd %d, device fd %d, and got DMA_BUF\n", + container_fd, dev_fd); + + setup_signals(); + + //////////////////////////////////////////////////////////////////////////////// + + /* Real basics: create DMABUF, and mmap it, and access MMIO through it. + * Do this for 2nd BAR if present, too (just plain memory). + */ + printf("\nTEST: Create DMABUF, map it\n"); + int bar_db_fd = vfio_create_dmabuf(dev_fd, /* region */ 0, + /* offset */ 0, bar_region[0].size); + FAIL_IF(bar_db_fd < 0, "Can't create DMABUF, %d\n", errno); + + volatile uint32_t *dbbar0 = + mmap_resource(bar_region[0].size, bar_db_fd, 0); + + printf("-i- Mapped DMABUF BAR0 at %p+0x%llx\n", dbbar0, + bar_region[0].size); + check_mmio(dbbar0); + + /* TEST: Map the traditional VFIO one _second_; it should still work. */ + printf("\nTEST: Map the regular VFIO BAR\n"); + volatile uint32_t *vfiobar = + mmap_resource(bar_region[0].size, dev_fd, bar_region[0].offset); + + printf("-i- Mapped VIRTIO BAR0 at %p+0x%llx\n", vfiobar, + bar_region[0].size); + check_mmio(vfiobar); + + /* Test plan: + * + * - Revoke the first DMABUF, check for fault + * - Check VFIO BAR access still works + * - Revoke first DMABUF fd again: -EBADFD + * - create new DMABUF for same (previously-revoked) region: accessible + * + * - Create overlapping DMABUFs: map success, maps alias OK + * - Create a second mapping of the second DMABUF, maps alias OK + * - Destroy one by revoking through a dup()ed fd: check mapping revoked + * - Check original is still accessible + * + * If we have a larger (>4K of accessible stuff!) second BAR resource: + * - Map it, create an overlapping alias with offset != 0 + * - Check alias/offset is sane + * + * Last: + * - close container_fd and dev_fd: check DMABUF mapping revoked + * - try revoking a non-DMABUF fd: -EINVAL + */ + + printf("\nTEST: Revocation of first DMABUF\n"); + r = revoke_dmabuf(dev_fd, bar_db_fd); + FAIL_IF(r != 0, "Can't revoke: %d\n", errno); + + if (sigsetjmp(jmpbuf, 1) == 0) { + // Try an access: expect BOOM + check_mmio(dbbar0); + FAIL_IF(true, "Expecting fault after revoke!\n"); + } + printf("-i- Revoked OK\n"); + + printf("\nTEST: Access through VFIO-mapped region still works\n"); + if (sigsetjmp(jmpbuf, 1) == 0) + check_mmio(vfiobar); + else + FAIL_IF(true, "Expecting VFIO-mapped BAR to still work!\n"); + + printf("\nTEST: Double-revoke\n"); + r = revoke_dmabuf(dev_fd, bar_db_fd); + FAIL_IF(r != -1 || errno != EBADFD, + "Expecting 2nd revoke to give EBADFD, got %d errno %d\n", r, + errno); + printf("-i- Correctly failed second revoke\n"); + + printf("\nTEST: Can't mmap() revoked DMABUF\n"); + void *dbfail = mmap(0, bar_region[1].size, PROT_READ | PROT_WRITE, + MAP_SHARED, bar_db_fd, 0); + FAIL_IF(dbfail != MAP_FAILED, "mmap() should fail\n"); + printf("-i- OK\n"); + + printf("\nTEST: Recreate new DMABUF for previously-revoked region\n"); + int bar_db_fd_2 = vfio_create_dmabuf( + dev_fd, /* region */ 0, /* offset */ 0, bar_region[0].size); + FAIL_IF(bar_db_fd_2 < 0, "Can't create DMABUF, %d\n", errno); + + volatile uint32_t *dbbar0_2 = + mmap_resource(bar_region[0].size, bar_db_fd_2, 0); + + printf("-i- Mapped 2nd DMABUF BAR0 at %p+0x%llx\n", dbbar0_2, + bar_region[0].size); + check_mmio(dbbar0_2); + + munmap((void *)dbbar0, bar_region[0].size); + close(bar_db_fd); + + printf("\nTEST: Create aliasing/overlapping DMABUF\n"); + int bar_db_fd_3 = vfio_create_dmabuf( + dev_fd, /* region */ 0, /* offset */ 0, bar_region[0].size); + FAIL_IF(bar_db_fd_3 < 0, "Can't create DMABUF, %d\n", errno); + + volatile uint32_t *dbbar0_3 = + mmap_resource(bar_region[0].size, bar_db_fd_3, 0); + + printf("-i- Mapped 3rd DMABUF BAR0 at %p+0x%llx\n", dbbar0_3, + bar_region[0].size); + check_mmio(dbbar0_3); + + /* Basic aliasing check: Write value through 2nd, read back through 3rd */ + uint32_t v; + + dbbar0_2[EDU_REG_INVERT / 4] = 0xfacecace; + v = dbbar0_3[EDU_REG_INVERT / 4]; + FAIL_IF(v != ~0xfacecace, + "Alias inverted MMIO value %08x bad (should be %08x)\n", v, + ~0xfacecace); + printf("-i- Aliasing DMABUF OK\n"); + + printf("\nTEST: Create a double-mapping of DMABUF\n"); + /* Create another mmap of the existing aliasing DMABUF fd */ + volatile uint32_t *dbbar0_3_2 = + mmap_resource(bar_region[0].size, bar_db_fd_3, 0); + + printf("-i- Mapped 3rd DMABUF BAR0 _again_ at %p+0x%llx\n", dbbar0_3_2, + bar_region[0].size); + /* Can we see the value we wrote before? */ + v = dbbar0_3_2[EDU_REG_INVERT / 4]; + FAIL_IF(v != ~0xfacecace, + "Alias alias inverted MMIO value %08x bad (should be %08x)\n", + v, ~0xfacecace); + check_mmio(dbbar0_3_2); + + printf("\nTEST: revoke aliasing DMABUF through dup()ed fd\n"); + int dup_dbfd3 = dup(bar_db_fd_3); + + r = revoke_dmabuf(dev_fd, dup_dbfd3); + FAIL_IF(r != 0, "Can't revoke: %d\n", errno); + + /* Both of the mmap()s made should now be gone */ + if (sigsetjmp(jmpbuf, 1) == 0) { + check_mmio(dbbar0_3); + FAIL_IF(true, "Expecting fault on 1st mmap after revoke!\n"); + } + + if (sigsetjmp(jmpbuf, 1) == 0) { + check_mmio(dbbar0_3_2); + FAIL_IF(true, "Expecting fault on 2nd mmap after revoke!\n"); + } + printf("-i- Both aliasing DMABUF mappings revoked OK\n"); + + close(dup_dbfd3); + close(bar_db_fd_3); + munmap((void *)dbbar0_3, bar_region[0].size); + munmap((void *)dbbar0_3_2, bar_region[0].size); + + /* And finally, although the aliasing DMABUF is gone, access + * through the original one should still work: + */ + if (sigsetjmp(jmpbuf, 1) == 0) + check_mmio(dbbar0_2); + else + FAIL_IF(true, + "Expecting original DMABUF mapping to still work!\n"); + printf("-i- Aliasing DMABUF removal OK, original still accessible\n"); + + /* If we're attached to a hacked/extended QEMU EDU device with + * a large memory region 1 then we can test things like + * offsets/aliasing. + */ + if (num_regions >= 2) { + printf("\nTEST: Second BAR: test overlapping+offset DMABUF\n"); + + printf("-i- Region 1 DMABUF: offset %llx, size %llx\n", + bar_region[1].offset, bar_region[1].size); + int bar1_db_fd = + vfio_create_dmabuf(dev_fd, 1, 0, bar_region[1].size); + + FAIL_IF(bar1_db_fd < 0, "Can't create DMABUF, %d\n", errno); + + volatile uint32_t *dbbar1 = mmap_resource_aligned( + bar_region[1].size, MiB(32), bar1_db_fd, 0); + printf("-i- Mapped DMABUF Region 1 at %p+0x%llx\n", dbbar1, + bar_region[1].size); + + /* Init with known values */ + for (unsigned long i = 0; i < (bar_region[1].size); + i += getpagesize()) + dbbar1[i / 4] = 0xca77face ^ i; + + v = dbbar1[0]; + FAIL_IF(v != 0xca77face, + "DB Region 1 read: Magic value %08x incorrect\n", v); + printf("-i- DB Region 1 read: Magic: 0x%08x\n", v); + + /* TEST: Overlap/aliasing; map same BAR with a range + * offset > 0. Also test disjoint/multi-range DMABUFs + * by creating a second range. This appears as one + * contiguous VA range mapped to a first BAR range + * (starting from range0_offset), then skipping a few + * physical pages, then a second range (starting at + * range1_offset). + */ + unsigned long range0_offset = getpagesize() * 3; + unsigned long range1_skip_pages = 5; + unsigned long range1_skip = getpagesize() * range1_skip_pages; + unsigned long range_size = + (bar_region[1].size - range0_offset - range1_skip) / 2; + unsigned long range1_offset = + range0_offset + range_size + range1_skip; + unsigned long map_size = range_size * 2; + + printf("\nTEST: Second BAR aliasing mapping, two ranges size 0x%lx:\n\t\t0x%lx-0x%lx, 0x%lx-0x%lx\n", + range_size, range0_offset, range0_offset + range_size, + range1_offset, range1_offset + range_size); + + int bar1_2_db_fd = vfio_create_dmabuf_dual( + dev_fd, 1, range0_offset, range_size, range1_offset, + range_size); + FAIL_IF(bar1_2_db_fd < 0, "Can't create DMABUF, %d\n", errno); + + volatile uint32_t *dbbar1_2 = + mmap_resource(map_size, bar1_2_db_fd, 0); + + printf("-i- Mapped DMABUF Region 1 alias at %p+0x%lx\n", + dbbar1_2, map_size); + FAIL_IF(dbbar1_2[0] != dbbar1[range0_offset / 4], + "slice2 value mismatch\n"); + + dbbar1[(range0_offset + 4) / 4] = 0xfacef00d; + /* Check we can see the value written above at +offset + * from offset 0 of this mapping (since the DMABUF + * itself is offsetted): + */ + v = dbbar1_2[4 / 4]; + FAIL_IF(v != 0xfacef00d, + "DB Region 1 alias read: Magic value %08x incorrect\n", + v); + printf("-i- DB Region 1 alias read: Magic 0x%08x, OK\n", v); + + /* Read back the known values across the two + * sub-ranges of the dbbar1_2 mapping, accounting for + * the physical pages skipped between them + */ + for (unsigned long i = 0; i < range_size; i += getpagesize()) { + unsigned long t = i + range0_offset; + uint32_t want = (0xca77face ^ t); + + v = dbbar1_2[i / 4]; + FAIL_IF(v != want, + "Expected %08x (got %08x) from range0 +%08lx (real %08lx)\n", + want, v, i, t); + } + for (unsigned long i = range_size; i < (range_size * 2); + i += getpagesize()) { + unsigned long t = i + range1_offset - range_size; + uint32_t want = (0xca77face ^ t); + + v = dbbar1_2[i / 4]; + FAIL_IF(v != want, + "Expected %08x (got %08x) from range1 +%08lx (real %08lx)\n", + want, v, i, t); + } + + printf("\nTEST: Third BAR aliasing mapping, testing mmap() non-zero offset:\n"); + + unsigned long smaller = range_size - 0x1000; + volatile uint32_t *dbbar1_3 = mmap_resource_aligned( + smaller, MiB(32), bar1_2_db_fd, range_size); + printf("-i- Mapped DMABUF Region 1 range 1 alias at %p+0x%lx\n", + dbbar1_3, smaller); + + for (unsigned long i = 0; i < smaller; i += getpagesize()) { + unsigned long t = i + range1_offset; + uint32_t want = (0xca77face ^ t); + + v = dbbar1_3[i / 4]; + FAIL_IF(v != want, + "Expected %08x (got %08x) from 3rd range1 +%08lx (real %08lx)\n", + want, v, i, t); + } + printf("-i- mmap offset OK\n"); + + /* TODO: If we can observe hugepages (mechanically, + * rather than human reading debug), we can test + * interesting alignment cases for the PFN search: + * + * - Deny hugepages at start/end of an mmap() that + * starts/ends at non-HP-aligned addresses + * (e.g. first pages are small, middle is fully + * aligned in VA and PFN so 2M, and buffer finishes + * before 2M boundary, so last pages are small). + * + * - Everything aligned nicely except the mmap() size + * is <2MB, so hugepage denied due to straddling + * end. + * + * - Buffer offsets into BAR not aligned, so no huge + * mappings even if mmap() is perfectly aligned. + */ + + /* Check that access after DMABUF fd close still works + * (VMA still holds refcount, obvs!) + */ + close(bar1_2_db_fd); + if (sigsetjmp(jmpbuf, 1) == 0) + v = dbbar1_2[0x4 / 4]; + else + FAIL_IF(true, + "Expecting original DMABUF mapping to still work!\n"); + printf("-i- DB Region 1 alias read 2: Magic 0x%08x, OK\n", v); + printf("-i- Offset check OK\n"); + } + + printf("\nTEST: Shutdown: close VFIO container/device fds, check DMABUF gone\n"); + + /* Final use of dev_fd: use it to try to revoke a non-DMABUF fd: */ + r = revoke_dmabuf(dev_fd, 1); + FAIL_IF(r != -1 || errno != EINVAL, + "Expecting revoke of stdout to give EINVAL, got %d errno %d\n", + r, errno); + printf("-i- Correctly failed final revoke\n"); + + /* Closing all uses of dev_fd (including the VFIO BAR mmap()!) + * will revoke the DMABUF; even though the DMABUF fd might + * remain open, the mapping itself is zapped. Start with a + * plain close (before unmapping the VFIO BAR mapping): + */ + close(dev_fd); + close(container_fd); + printf("-i- VFIO fds closed\n"); + + if (sigsetjmp(jmpbuf, 1) == 0) + check_mmio(dbbar0_2); + else + FAIL_IF(true, + "Expecting DMABUF mapping to still work if VFIO mapping still live!\n"); + + if (sigsetjmp(jmpbuf, 1) == 0) + check_mmio(vfiobar); + else + FAIL_IF(true, + "Expecting VFIO BAR mapping to still work after fd close!\n"); + + munmap((void *)vfiobar, bar_region[0].size); + printf("-i- VFIO BAR unmapped\n"); + + /* The final reference via VFIO should now be gone, and the + * DMABUF should now be destroyed. The mapping of it should + * be inaccessible: + */ + if (sigsetjmp(jmpbuf, 1) == 0) { + check_mmio(dbbar0_2); + FAIL_IF(true, + "Expecting DMABUF mapping to fault after VFIO fd shutdown!\n"); + } + printf("-i- DMABUF mappings inaccessible\n"); + + /* Ensure we can't mmap() DMABUF for closed device */ + void *dbfail2 = mmap(0, bar_region[1].size, PROT_READ | PROT_WRITE, + MAP_SHARED, bar_db_fd_2, 0); + FAIL_IF(dbfail2 != MAP_FAILED, "mmap() should fail\n"); + printf("-i- Can't mmap DMABUF for closed device, OK\n"); + + munmap((void *)dbbar0_2, bar_region[0].size); + close(bar_db_fd_2); + + printf("\nPASS\n"); + + return 0; +} + +static void usage(char *me) +{ + printf("Usage:\t%s -g <group_number> -r <RID/BDF>\n" + "\n" + "\t\tGroup is found via device path, e.g. cat /sys/bus/pci/devices/0000:03:1d.0/iommu_group\n" + "\t\tRID is of the form 0000:03:1d.0\n" + "\n", + me); +} + +int main(int argc, char *argv[]) +{ + /* Get args: IOMMU group and BDF/path */ + int groupnr = -1; + char *rid_str = NULL; + int arg; + + while ((arg = getopt(argc, argv, "g:r:h")) != -1) { + switch (arg) { + case 'g': + groupnr = atoi(optarg); + break; + + case 'r': + rid_str = strdup(optarg); + break; + case 'h': + default: + usage(argv[0]); + return 1; + } + } + + if (rid_str == NULL || groupnr == -1) { + usage(argv[0]); + return 1; + } + + printf("-i- Using group number %d, RID '%s'\n", groupnr, rid_str); + + return vfio_dmabuf_test(groupnr, rid_str); +}