Commit f12e0d22 authored by Keqian Zhu's avatar Keqian Zhu Committed by Will Deacon
Browse files

iommu: Defer the early return in arm_(v7s/lpae)_map 



Although handling a mapping request with no permissions is a
trivial no-op, defer the early return until after the size/range
checks so that we are consistent with other mapping requests.

Signed-off-by: default avatarKeqian Zhu <zhukeqian1@huawei.com>
Link: https://lore.kernel.org/r/20201207115758.9400-1-zhukeqian1@huawei.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 093b32a8

drivers/iommu/io-pgtable-arm-v7s.c

+4 −4
Original line number Diff line number Diff line
@@ -522,14 +522,14 @@ static int arm_v7s_map(struct io_pgtable_ops *ops, unsigned long iova, 
	struct io_pgtable *iop = &data->iop;

	int ret;



	/* If no access, then nothing to do */

	if (!(prot & (IOMMU_READ | IOMMU_WRITE)))

		return 0;



	if (WARN_ON(iova >= (1ULL << data->iop.cfg.ias) ||

		    paddr >= (1ULL << data->iop.cfg.oas)))

		return -ERANGE;



	/* If no access, then nothing to do */

	if (!(prot & (IOMMU_READ | IOMMU_WRITE)))

		return 0;



	ret = __arm_v7s_map(data, iova, paddr, size, prot, 1, data->pgd, gfp);

	/*

	 * Synchronise all PTE updates for the new mapping before there's

drivers/iommu/io-pgtable-arm.c

+4 −4
Original line number Diff line number Diff line
@@ -444,10 +444,6 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova, 
	arm_lpae_iopte prot;

	long iaext = (s64)iova >> cfg->ias;



	/* If no access, then nothing to do */

	if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))

		return 0;



	if (WARN_ON(!size || (size & cfg->pgsize_bitmap) != size))

		return -EINVAL;
@@ -456,6 +452,10 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova, 
	if (WARN_ON(iaext || paddr >> cfg->oas))

		return -ERANGE;



	/* If no access, then nothing to do */

	if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))

		return 0;



	prot = arm_lpae_prot_to_pte(data, iommu_prot);

	ret = __arm_lpae_map(data, iova, paddr, size, prot, lvl, ptep, gfp);

	/*

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