[PATCH 4/4] ARM: dma-mapping: Skip cache maint for invalid page

[Hiroshi Doyu]

Skip cache maint for invalid page but warn it.

Signed-off-by: Hiroshi Doyu <hdoyu at nvidia.com>
---
 arch/arm/mm/dma-mapping.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 2621282..0368702 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1589,6 +1589,9 @@ static void arm_iommu_unmap_page(struct device *dev, dma_addr_t handle,
 	if (!iova)
 		return;
 
+	if (WARN_ON(!pfn_valid(page_to_pfn(page))))
+		return;
+
 	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
 		__dma_page_dev_to_cpu(page, offset, size, dir);
 
@@ -1607,6 +1610,9 @@ static void arm_iommu_sync_single_for_cpu(struct device *dev,
 	if (!iova)
 		return;
 
+	if (WARN_ON(!pfn_valid(page_to_pfn(page))))
+		return;
+
 	__dma_page_dev_to_cpu(page, offset, size, dir);
 }
 
@@ -1621,6 +1627,9 @@ static void arm_iommu_sync_single_for_device(struct device *dev,
 	if (!iova)
 		return;
 
+	if (WARN_ON(!pfn_valid(page_to_pfn(page))))
+		return;
+
 	__dma_page_cpu_to_dev(page, offset, size, dir);
 }
 
-- 
1.7.5.4