Commit bdc8c00c authored by Kunkun Jiang's avatar Kunkun Jiang Committed by Zheng Zengkai
Browse files

iommu/io-pgtable-arm: Add and realize clear_dirty_log ops 

virt inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I3ZUKK


CVE: NA

------------------------------

After dirty log is retrieved, user should clear dirty log to re-enable
dirty log tracking for these dirtied pages. This clears the dirty state
(As we just set DBM bit for stage1 mapping, so should set the AP[2] bit)
of these leaf TTDs that are specified by the user provided bitmap.

Co-developed-by: default avatarKeqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: default avatarKunkun Jiang <jiangkunkun@huawei.com>
Reviewed-by: default avatarKeqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent f92820e8

drivers/iommu/io-pgtable-arm.c

+93 −0
Original line number Diff line number Diff line
@@ -966,6 +966,98 @@ static int arm_lpae_sync_dirty_log(struct io_pgtable_ops *ops, 
					 bitmap, base_iova, bitmap_pgshift);

}



static int __arm_lpae_clear_dirty_log(struct arm_lpae_io_pgtable *data,

				      unsigned long iova, size_t size,

				      int lvl, arm_lpae_iopte *ptep,

				      unsigned long *bitmap,

				      unsigned long base_iova,

				      unsigned long bitmap_pgshift)

{

	arm_lpae_iopte pte;

	struct io_pgtable *iop = &data->iop;

	unsigned long offset;

	size_t base, next_size;

	int nbits, ret, i;



	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))

		return -EINVAL;



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

	pte = READ_ONCE(*ptep);

	if (WARN_ON(!pte))

		return -EINVAL;



	if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {

		if (iopte_leaf(pte, lvl, iop->fmt)) {

			if (pte & ARM_LPAE_PTE_AP_RDONLY)

				return 0;



			/* Ensure all corresponding bits are set */

			nbits = size >> bitmap_pgshift;

			offset = (iova - base_iova) >> bitmap_pgshift;

			for (i = offset; i < offset + nbits; i++) {

				if (!test_bit(i, bitmap))

					return 0;

			}



			/* Race does not exist */

			pte |= ARM_LPAE_PTE_AP_RDONLY;

			__arm_lpae_set_pte(ptep, pte, &iop->cfg);

			return 0;

		}

		/* Current level is table, traverse next level */

		next_size = ARM_LPAE_BLOCK_SIZE(lvl + 1, data);

		ptep = iopte_deref(pte, data);

		for (base = 0; base < size; base += next_size) {

			ret = __arm_lpae_clear_dirty_log(data, iova + base,

					next_size, lvl + 1, ptep, bitmap,

					base_iova, bitmap_pgshift);

			if (ret)

				return ret;

		}

		return 0;

	} else if (iopte_leaf(pte, lvl, iop->fmt)) {

		/* Though the size is too small, it is already clean */

		if (pte & ARM_LPAE_PTE_AP_RDONLY)

			return 0;



		return -EINVAL;

	}



	/* Keep on walkin */

	ptep = iopte_deref(pte, data);

	return __arm_lpae_clear_dirty_log(data, iova, size, lvl + 1, ptep,

			bitmap, base_iova, bitmap_pgshift);

}



static int arm_lpae_clear_dirty_log(struct io_pgtable_ops *ops,

				    unsigned long iova, size_t size,

				    unsigned long *bitmap,

				    unsigned long base_iova,

				    unsigned long bitmap_pgshift)

{

	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);

	struct io_pgtable_cfg *cfg = &data->iop.cfg;

	arm_lpae_iopte *ptep = data->pgd;

	int lvl = data->start_level;

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



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

		return -EINVAL;



	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)

		iaext = ~iaext;

	if (WARN_ON(iaext))

		return -EINVAL;



	if (data->iop.fmt != ARM_64_LPAE_S1 &&

	    data->iop.fmt != ARM_32_LPAE_S1)

		return -EINVAL;



	return __arm_lpae_clear_dirty_log(data, iova, size, lvl, ptep,

			bitmap, base_iova, bitmap_pgshift);

}



static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)

{

	unsigned long granule, page_sizes;
@@ -1047,6 +1139,7 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg) 
		.split_block	= arm_lpae_split_block,

		.merge_page	= arm_lpae_merge_page,

		.sync_dirty_log	= arm_lpae_sync_dirty_log,

		.clear_dirty_log = arm_lpae_clear_dirty_log,

	};



	return data;

include/linux/io-pgtable.h

+4 −0
Original line number Diff line number Diff line
@@ -175,6 +175,10 @@ struct io_pgtable_ops { 
			      unsigned long iova, size_t size,

			      unsigned long *bitmap, unsigned long base_iova,

			      unsigned long bitmap_pgshift);

	int (*clear_dirty_log)(struct io_pgtable_ops *ops,

			       unsigned long iova, size_t size,

			       unsigned long *bitmap, unsigned long base_iova,

			       unsigned long bitmap_pgshift);

};



/**