--- zzzz-none-000/linux-3.10.107/arch/x86/kernel/pci-dma.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/x86/kernel/pci-dma.c	2021-02-04 17:41:59.000000000 +0000
@@ -58,17 +58,6 @@
 /* Number of entries preallocated for DMA-API debugging */
 #define PREALLOC_DMA_DEBUG_ENTRIES       65536
 
-int dma_set_mask(struct device *dev, u64 mask)
-{
-	if (!dev->dma_mask || !dma_supported(dev, mask))
-		return -EIO;
-
-	*dev->dma_mask = mask;
-
-	return 0;
-}
-EXPORT_SYMBOL(dma_set_mask);
-
 void __init pci_iommu_alloc(void)
 {
 	struct iommu_table_entry *p;
@@ -97,12 +86,17 @@
 
 	dma_mask = dma_alloc_coherent_mask(dev, flag);
 
-	flag |= __GFP_ZERO;
+	flag &= ~__GFP_ZERO;
 again:
 	page = NULL;
 	/* CMA can be used only in the context which permits sleeping */
-	if (flag & __GFP_WAIT)
+	if (gfpflags_allow_blocking(flag)) {
 		page = dma_alloc_from_contiguous(dev, count, get_order(size));
+		if (page && page_to_phys(page) + size > dma_mask) {
+			dma_release_from_contiguous(dev, page, count);
+			page = NULL;
+		}
+	}
 	/* fallback */
 	if (!page)
 		page = alloc_pages_node(dev_to_node(dev), flag, get_order(size));
@@ -120,7 +114,7 @@
 
 		return NULL;
 	}
-
+	memset(page_address(page), 0, size);
 	*dma_addr = addr;
 	return page_address(page);
 }
@@ -135,6 +129,21 @@
 		free_pages((unsigned long)vaddr, get_order(size));
 }
 
+bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp)
+{
+	if (!*dev)
+		*dev = &x86_dma_fallback_dev;
+
+	*gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
+	*gfp = dma_alloc_coherent_gfp_flags(*dev, *gfp);
+
+	if (!is_device_dma_capable(*dev))
+		return false;
+	return true;
+
+}
+EXPORT_SYMBOL(arch_dma_alloc_attrs);
+
 /*
  * See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
  * parameter documentation.