diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index a1196f45d38841e31dc17f446ed9dfcbc9de4391..abc48c76c770c87c45f59e134a97bb0705f6d2bd 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -79,6 +79,8 @@
 #define ARM_LPAE_PTE_SH_IS		(((arm_lpae_iopte)3) << 8)
 #define ARM_LPAE_PTE_NS			(((arm_lpae_iopte)1) << 5)
 #define ARM_LPAE_PTE_VALID		(((arm_lpae_iopte)1) << 0)
+/* Block descriptor bits */
+#define ARM_LPAE_PTE_NT			(((arm_lpae_iopte)1) << 16)
 
 #define ARM_LPAE_PTE_ATTR_LO_MASK	(((arm_lpae_iopte)0x3ff) << 2)
 /* Ignore the contiguous bit for block splitting */
@@ -680,6 +682,125 @@ static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
 	return iopte_to_paddr(pte, data) | iova;
 }
 
+static size_t __arm_lpae_split_block(struct arm_lpae_io_pgtable *data,
+				     unsigned long iova, size_t size, int lvl,
+				     arm_lpae_iopte *ptep);
+
+static size_t arm_lpae_do_split_blk(struct arm_lpae_io_pgtable *data,
+				    unsigned long iova, size_t size,
+				    arm_lpae_iopte blk_pte, int lvl,
+				    arm_lpae_iopte *ptep)
+{
+	struct io_pgtable_cfg *cfg = &data->iop.cfg;
+	arm_lpae_iopte pte, *tablep;
+	phys_addr_t blk_paddr;
+	size_t tablesz = ARM_LPAE_GRANULE(data);
+	size_t split_sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
+	int i;
+
+	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
+		return 0;
+
+	tablep = __arm_lpae_alloc_pages(tablesz, GFP_ATOMIC, cfg);
+	if (!tablep)
+		return 0;
+
+	blk_paddr = iopte_to_paddr(blk_pte, data);
+	pte = iopte_prot(blk_pte);
+	for (i = 0; i < tablesz / sizeof(pte); i++, blk_paddr += split_sz)
+		__arm_lpae_init_pte(data, blk_paddr, pte, lvl, &tablep[i]);
+
+	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_BBML1) {
+		/* Race does not exist */
+		blk_pte |= ARM_LPAE_PTE_NT;
+		__arm_lpae_set_pte(ptep, blk_pte, cfg);
+		io_pgtable_tlb_flush_walk(&data->iop, iova, size, size);
+	}
+	/* Race does not exist */
+	pte = arm_lpae_install_table(tablep, ptep, blk_pte, cfg);
+
+	/* Have splited it into page? */
+	if (lvl == (ARM_LPAE_MAX_LEVELS - 1))
+		return size;
+
+	/* Go back to lvl - 1 */
+	ptep -= ARM_LPAE_LVL_IDX(iova, lvl - 1, data);
+	return __arm_lpae_split_block(data, iova, size, lvl - 1, ptep);
+}
+
+static size_t __arm_lpae_split_block(struct arm_lpae_io_pgtable *data,
+				     unsigned long iova, size_t size, int lvl,
+				     arm_lpae_iopte *ptep)
+{
+	arm_lpae_iopte pte;
+	struct io_pgtable *iop = &data->iop;
+	size_t base, next_size, total_size;
+
+	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
+		return 0;
+
+	ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
+	pte = READ_ONCE(*ptep);
+	if (WARN_ON(!pte))
+		return 0;
+
+	if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
+		if (iopte_leaf(pte, lvl, iop->fmt)) {
+			if (lvl == (ARM_LPAE_MAX_LEVELS - 1) ||
+			    (pte & ARM_LPAE_PTE_AP_RDONLY))
+				return size;
+
+			/* We find a writable block, split it. */
+			return arm_lpae_do_split_blk(data, iova, size, pte,
+					lvl + 1, ptep);
+		} else {
+			/* If it is the last table level, then nothing to do */
+			if (lvl == (ARM_LPAE_MAX_LEVELS - 2))
+				return size;
+
+			total_size = 0;
+			next_size = ARM_LPAE_BLOCK_SIZE(lvl + 1, data);
+			ptep = iopte_deref(pte, data);
+			for (base = 0; base < size; base += next_size)
+				total_size += __arm_lpae_split_block(data,
+						iova + base, next_size, lvl + 1,
+						ptep);
+			return total_size;
+		}
+	} else if (iopte_leaf(pte, lvl, iop->fmt)) {
+		WARN(1, "Can't split behind a block.\n");
+		return 0;
+	}
+
+	/* Keep on walkin */
+	ptep = iopte_deref(pte, data);
+	return __arm_lpae_split_block(data, iova, size, lvl + 1, ptep);
+}
+
+static size_t arm_lpae_split_block(struct io_pgtable_ops *ops,
+				   unsigned long iova, size_t size)
+{
+	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 0;
+
+	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
+		iaext = ~iaext;
+	if (WARN_ON(iaext))
+		return 0;
+
+	/* If it is smallest granule, then nothing to do */
+	if (size == ARM_LPAE_BLOCK_SIZE(ARM_LPAE_MAX_LEVELS - 1, data))
+		return size;
+
+	return __arm_lpae_split_block(data, iova, size, lvl, ptep);
+}
+
 static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)
 {
 	unsigned long granule, page_sizes;
@@ -758,6 +879,7 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
 		.map		= arm_lpae_map,
 		.unmap		= arm_lpae_unmap,
 		.iova_to_phys	= arm_lpae_iova_to_phys,
+		.split_block	= arm_lpae_split_block,
 	};
 
 	return data;
diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index adcece3b1d55a2f7ded4694d2ba529d36c8de731..8a8711baa4f17838c59d7d54084be15fc9cdb85e 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -167,6 +167,8 @@ struct io_pgtable_ops {
 			size_t size, struct iommu_iotlb_gather *gather);
 	phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
 				    unsigned long iova);
+	size_t (*split_block)(struct io_pgtable_ops *ops, unsigned long iova,
+			      size_t size);
 };
 
 /**