[PATCH v2 04/14] iommu/io-pgtable-arm-v7s: Add paddr_to_iopte and iopte_to_paddr helpers

[Yong Wu]

Add two helper functions: paddr_to_iopte and iopte_to_paddr.

Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
---
 drivers/iommu/io-pgtable-arm-v7s.c | 45 ++++++++++++++++++++++++++++----------
 1 file changed, 33 insertions(+), 12 deletions(-)

diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
index b5948ba..fa3b9ec 100644
--- a/drivers/iommu/io-pgtable-arm-v7s.c
+++ b/drivers/iommu/io-pgtable-arm-v7s.c
@@ -173,18 +173,38 @@ struct arm_v7s_io_pgtable {
 	spinlock_t		split_lock;
 };
 
+static bool arm_v7s_pte_is_cont(arm_v7s_iopte pte, int lvl);
+
 static dma_addr_t __arm_v7s_dma_addr(void *pages)
 {
 	return (dma_addr_t)virt_to_phys(pages);
 }
 
-static arm_v7s_iopte *iopte_deref(arm_v7s_iopte pte, int lvl)
+static arm_v7s_iopte paddr_to_iopte(phys_addr_t paddr, int lvl,
+				    struct arm_v7s_io_pgtable *data)
 {
+	return paddr & ARM_V7S_LVL_MASK(lvl);
+}
+
+static phys_addr_t iopte_to_paddr(arm_v7s_iopte pte, int lvl,
+				  struct arm_v7s_io_pgtable *data)
+{
+	arm_v7s_iopte mask;
+
 	if (ARM_V7S_PTE_IS_TABLE(pte, lvl))
-		pte &= ARM_V7S_TABLE_MASK;
+		mask = ARM_V7S_TABLE_MASK;
+	else if (arm_v7s_pte_is_cont(pte, lvl))
+		mask = ARM_V7S_LVL_MASK(lvl) * ARM_V7S_CONT_PAGES;
 	else
-		pte &= ARM_V7S_LVL_MASK(lvl);
-	return phys_to_virt(pte);
+		mask = ARM_V7S_LVL_MASK(lvl);
+
+	return pte & mask;
+}
+
+static arm_v7s_iopte *iopte_deref(arm_v7s_iopte pte, int lvl,
+				  struct arm_v7s_io_pgtable *data)
+{
+	return phys_to_virt(iopte_to_paddr(pte, lvl, data));
 }
 
 static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp,
@@ -396,7 +416,7 @@ static int arm_v7s_init_pte(struct arm_v7s_io_pgtable *data,
 	if (num_entries > 1)
 		pte = arm_v7s_pte_to_cont(pte, lvl);
 
-	pte |= paddr & ARM_V7S_LVL_MASK(lvl);
+	pte |= paddr_to_iopte(paddr, lvl, data);
 
 	__arm_v7s_set_pte(ptep, pte, num_entries, cfg);
 	return 0;
@@ -462,7 +482,7 @@ static int __arm_v7s_map(struct arm_v7s_io_pgtable *data, unsigned long iova,
 	}
 
 	if (ARM_V7S_PTE_IS_TABLE(pte, lvl)) {
-		cptep = iopte_deref(pte, lvl);
+		cptep = iopte_deref(pte, lvl, data);
 	} else if (pte) {
 		/* We require an unmap first */
 		WARN_ON(!selftest_running);
@@ -512,7 +532,8 @@ static void arm_v7s_free_pgtable(struct io_pgtable *iop)
 		arm_v7s_iopte pte = data->pgd[i];
 
 		if (ARM_V7S_PTE_IS_TABLE(pte, 1))
-			__arm_v7s_free_table(iopte_deref(pte, 1), 2, data);
+			__arm_v7s_free_table(iopte_deref(pte, 1, data),
+					     2, data);
 	}
 	__arm_v7s_free_table(data->pgd, 1, data);
 	kmem_cache_destroy(data->l2_tables);
@@ -582,7 +603,7 @@ static size_t arm_v7s_split_blk_unmap(struct arm_v7s_io_pgtable *data,
 		if (!ARM_V7S_PTE_IS_TABLE(pte, 1))
 			return 0;
 
-		tablep = iopte_deref(pte, 1);
+		tablep = iopte_deref(pte, 1, data);
 		return __arm_v7s_unmap(data, iova, size, 2, tablep);
 	}
 
@@ -640,7 +661,7 @@ static size_t __arm_v7s_unmap(struct arm_v7s_io_pgtable *data,
 				io_pgtable_tlb_add_flush(iop, iova, blk_size,
 					ARM_V7S_BLOCK_SIZE(lvl + 1), false);
 				io_pgtable_tlb_sync(iop);
-				ptep = iopte_deref(pte[i], lvl);
+				ptep = iopte_deref(pte[i], lvl, data);
 				__arm_v7s_free_table(ptep, lvl + 1, data);
 			} else {
 				io_pgtable_tlb_add_flush(iop, iova, blk_size,
@@ -658,7 +679,7 @@ static size_t __arm_v7s_unmap(struct arm_v7s_io_pgtable *data,
 	}
 
 	/* Keep on walkin' */
-	ptep = iopte_deref(pte[0], lvl);
+	ptep = iopte_deref(pte[0], lvl, data);
 	return __arm_v7s_unmap(data, iova, size, lvl + 1, ptep);
 }
 
@@ -684,7 +705,7 @@ static phys_addr_t arm_v7s_iova_to_phys(struct io_pgtable_ops *ops,
 	do {
 		ptep += ARM_V7S_LVL_IDX(iova, ++lvl);
 		pte = READ_ONCE(*ptep);
-		ptep = iopte_deref(pte, lvl);
+		ptep = iopte_deref(pte, lvl, data);
 	} while (ARM_V7S_PTE_IS_TABLE(pte, lvl));
 
 	if (!ARM_V7S_PTE_IS_VALID(pte))
@@ -693,7 +714,7 @@ static phys_addr_t arm_v7s_iova_to_phys(struct io_pgtable_ops *ops,
 	mask = ARM_V7S_LVL_MASK(lvl);
 	if (arm_v7s_pte_is_cont(pte, lvl))
 		mask *= ARM_V7S_CONT_PAGES;
-	return (pte & mask) | (iova & ~mask);
+	return iopte_to_paddr(pte, lvl, data) | (iova & ~mask);
 }
 
 static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg,
-- 
1.9.1