static int __init arm_lpae_run_tests()

in io-pgtable-arm.c [1234:1331]

• 64 lines of code
• 16 McCabe index (conditional complexity)

static int __init arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
{
	static const enum io_pgtable_fmt fmts[] __initconst = {
		ARM_64_LPAE_S1,
		ARM_64_LPAE_S2,
	};

	int i, j;
	unsigned long iova;
	size_t size;
	struct io_pgtable_ops *ops;

	selftest_running = true;

	for (i = 0; i < ARRAY_SIZE(fmts); ++i) {
		cfg_cookie = cfg;
		ops = alloc_io_pgtable_ops(fmts[i], cfg, cfg);
		if (!ops) {
			pr_err("selftest: failed to allocate io pgtable ops\n");
			return -ENOMEM;
		}

		/*
		 * Initial sanity checks.
		 * Empty page tables shouldn't provide any translations.
		 */
		if (ops->iova_to_phys(ops, 42))
			return __FAIL(ops, i);

		if (ops->iova_to_phys(ops, SZ_1G + 42))
			return __FAIL(ops, i);

		if (ops->iova_to_phys(ops, SZ_2G + 42))
			return __FAIL(ops, i);

		/*
		 * Distinct mappings of different granule sizes.
		 */
		iova = 0;
		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
			size = 1UL << j;

			if (ops->map(ops, iova, iova, size, IOMMU_READ |
							    IOMMU_WRITE |
							    IOMMU_NOEXEC |
							    IOMMU_CACHE, GFP_KERNEL))
				return __FAIL(ops, i);

			/* Overlapping mappings */
			if (!ops->map(ops, iova, iova + size, size,
				      IOMMU_READ | IOMMU_NOEXEC, GFP_KERNEL))
				return __FAIL(ops, i);

			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
				return __FAIL(ops, i);

			iova += SZ_1G;
		}

		/* Partial unmap */
		size = 1UL << __ffs(cfg->pgsize_bitmap);
		if (ops->unmap(ops, SZ_1G + size, size, NULL) != size)
			return __FAIL(ops, i);

		/* Remap of partial unmap */
		if (ops->map(ops, SZ_1G + size, size, size, IOMMU_READ, GFP_KERNEL))
			return __FAIL(ops, i);

		if (ops->iova_to_phys(ops, SZ_1G + size + 42) != (size + 42))
			return __FAIL(ops, i);

		/* Full unmap */
		iova = 0;
		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
			size = 1UL << j;

			if (ops->unmap(ops, iova, size, NULL) != size)
				return __FAIL(ops, i);

			if (ops->iova_to_phys(ops, iova + 42))
				return __FAIL(ops, i);

			/* Remap full block */
			if (ops->map(ops, iova, iova, size, IOMMU_WRITE, GFP_KERNEL))
				return __FAIL(ops, i);

			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
				return __FAIL(ops, i);

			iova += SZ_1G;
		}

		free_io_pgtable_ops(ops);
	}

	selftest_running = false;
	return 0;
}