Commit d9e589e6 authored by Rob Clark's avatar Rob Clark Committed by Will Deacon
Browse files

iommu/io-pgtable-arm: Re-use the pgtable walk for iova_to_phys 



Re-use the generic pgtable walk path.

Signed-off-by: default avatarRob Clark <robdclark@chromium.org>
Reviewed-by: default avatarMostafa Saleh <smostafa@google.com>
Link: https://lore.kernel.org/r/20241210165127.600817-3-robdclark@gmail.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 821500d5

drivers/iommu/io-pgtable-arm.c

+37 −37
Original line number Diff line number Diff line
@@ -704,42 +704,6 @@ static size_t arm_lpae_unmap_pages(struct io_pgtable_ops *ops, unsigned long iov 
				data->start_level, ptep);

}



static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,

					 unsigned long iova)

{

	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);

	arm_lpae_iopte pte, *ptep = data->pgd;

	int lvl = data->start_level;



	do {

		/* Valid IOPTE pointer? */

		if (!ptep)

			return 0;



		/* Grab the IOPTE we're interested in */

		ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);

		pte = READ_ONCE(*ptep);



		/* Valid entry? */

		if (!pte)

			return 0;



		/* Leaf entry? */

		if (iopte_leaf(pte, lvl, data->iop.fmt))

			goto found_translation;



		/* Take it to the next level */

		ptep = iopte_deref(pte, data);

	} while (++lvl < ARM_LPAE_MAX_LEVELS);



	/* Ran out of page tables to walk */

	return 0;



found_translation:

	iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1);

	return iopte_to_paddr(pte, data) | iova;

}



struct io_pgtable_walk_data {

	struct io_pgtable		*iop;

	void				*data;
@@ -755,6 +719,41 @@ static int __arm_lpae_iopte_walk(struct arm_lpae_io_pgtable *data, 
				 arm_lpae_iopte *ptep,

				 int lvl);



struct iova_to_phys_data {

	arm_lpae_iopte pte;

	int lvl;

};



static int visit_iova_to_phys(struct io_pgtable_walk_data *walk_data, int lvl,

			      arm_lpae_iopte *ptep, size_t size)

{

	struct iova_to_phys_data *data = walk_data->data;

	data->pte = *ptep;

	data->lvl = lvl;

	return 0;

}



static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,

					 unsigned long iova)

{

	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);

	struct iova_to_phys_data d;

	struct io_pgtable_walk_data walk_data = {

		.data = &d,

		.visit = visit_iova_to_phys,

		.addr = iova,

		.end = iova + 1,

	};

	int ret;



	ret = __arm_lpae_iopte_walk(data, &walk_data, data->pgd, data->start_level);

	if (ret)

		return 0;



	iova &= (ARM_LPAE_BLOCK_SIZE(d.lvl, data) - 1);

	return iopte_to_paddr(d.pte, data) | iova;

}



static int io_pgtable_visit(struct arm_lpae_io_pgtable *data,

			    struct io_pgtable_walk_data *walk_data,

			    arm_lpae_iopte *ptep, int lvl)
@@ -772,8 +771,9 @@ static int io_pgtable_visit(struct arm_lpae_io_pgtable *data, 
		return 0;

	}



	if (WARN_ON(!iopte_table(pte, lvl)))

	if (!iopte_table(pte, lvl)) {

		return -EINVAL;

	}



	ptep = iopte_deref(pte, data);

	return __arm_lpae_iopte_walk(data, walk_data, ptep, lvl + 1);