Add struct iova_allocator, which gives tests a convenient way to generate legally-accessible IOVAs to map.
This is based on Alex Williamson's patch series for adding an IOVA allocator [1]. [1] https://lore.kernel.org/all/[email protected]/ Signed-off-by: Alex Mastro <[email protected]> --- .../testing/selftests/vfio/lib/include/vfio_util.h | 14 +++++ tools/testing/selftests/vfio/lib/vfio_pci_device.c | 65 +++++++++++++++++++++- 2 files changed, 78 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/vfio/lib/include/vfio_util.h b/tools/testing/selftests/vfio/lib/include/vfio_util.h index fb5efec52316..bb1e7d39dfb9 100644 --- a/tools/testing/selftests/vfio/lib/include/vfio_util.h +++ b/tools/testing/selftests/vfio/lib/include/vfio_util.h @@ -13,6 +13,8 @@ #include "../../../kselftest.h" +#define ALIGN(x, a) (((x) + (a - 1)) & (~((a) - 1))) + #define VFIO_LOG_AND_EXIT(...) do { \ fprintf(stderr, " " __VA_ARGS__); \ fprintf(stderr, "\n"); \ @@ -188,6 +190,13 @@ struct vfio_pci_device { struct vfio_pci_driver driver; }; +struct iova_allocator { + struct iommu_iova_range *ranges; + size_t nranges; + size_t range_idx; + iova_t iova_next; +}; + /* * Return the BDF string of the device that the test should use. * @@ -212,6 +221,11 @@ void vfio_pci_device_reset(struct vfio_pci_device *device); struct iommu_iova_range *vfio_pci_iova_ranges(struct vfio_pci_device *device, size_t *nranges); +int iova_allocator_init(struct vfio_pci_device *device, + struct iova_allocator *allocator); +void iova_allocator_deinit(struct iova_allocator *allocator); +iova_t iova_allocator_alloc(struct iova_allocator *allocator, size_t size); + int __vfio_pci_dma_map(struct vfio_pci_device *device, struct vfio_dma_region *region); int __vfio_pci_dma_unmap(struct vfio_pci_device *device, diff --git a/tools/testing/selftests/vfio/lib/vfio_pci_device.c b/tools/testing/selftests/vfio/lib/vfio_pci_device.c index 6bedbe65f0a1..a634feb1d378 100644 --- a/tools/testing/selftests/vfio/lib/vfio_pci_device.c +++ b/tools/testing/selftests/vfio/lib/vfio_pci_device.c @@ -12,11 +12,12 @@ #include <sys/mman.h> #include <uapi/linux/types.h> +#include <linux/iommufd.h> #include <linux/limits.h> #include <linux/mman.h> +#include <linux/overflow.h> #include <linux/types.h> #include <linux/vfio.h> -#include <linux/iommufd.h> #include "../../../kselftest.h" #include <vfio_util.h> @@ -190,6 +191,68 @@ struct iommu_iova_range *vfio_pci_iova_ranges(struct vfio_pci_device *device, return ranges; } +int iova_allocator_init(struct vfio_pci_device *device, + struct iova_allocator *allocator) +{ + struct iommu_iova_range *ranges; + size_t nranges; + + memset(allocator, 0, sizeof(*allocator)); + + ranges = vfio_pci_iova_ranges(device, &nranges); + if (!ranges) + return -ENOENT; + + *allocator = (struct iova_allocator){ + .ranges = ranges, + .nranges = nranges, + .range_idx = 0, + .iova_next = 0, + }; + + return 0; +} + +void iova_allocator_deinit(struct iova_allocator *allocator) +{ + free(allocator->ranges); +} + +iova_t iova_allocator_alloc(struct iova_allocator *allocator, size_t size) +{ + int idx = allocator->range_idx; + struct iommu_iova_range *range = &allocator->ranges[idx]; + + VFIO_ASSERT_LT(idx, allocator->nranges, "IOVA allocator out of space\n"); + VFIO_ASSERT_GT(size, 0, "Invalid size arg, zero\n"); + VFIO_ASSERT_EQ(size & (size - 1), 0, "Invalid size arg, non-power-of-2\n"); + + for (;;) { + iova_t iova, last; + + iova = ALIGN(allocator->iova_next, size); + + if (iova < allocator->iova_next || iova > range->last || + check_add_overflow(iova, size - 1, &last) || + last > range->last) { + allocator->range_idx = ++idx; + VFIO_ASSERT_LT(idx, allocator->nranges, + "Out of ranges for allocation\n"); + allocator->iova_next = (++range)->start; + continue; + } + + if (check_add_overflow(last, (iova_t)1, &allocator->iova_next) || + allocator->iova_next > range->last) { + allocator->range_idx = ++idx; + if (idx < allocator->nranges) + allocator->iova_next = (++range)->start; + } + + return iova; + } +} + iova_t __to_iova(struct vfio_pci_device *device, void *vaddr) { struct vfio_dma_region *region; -- 2.47.3
