1 files changed, 47 insertions, 0 deletions

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index f8afc6dcc29f..e8cef1ad0fe3 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -681,3 +681,50 @@ xen_swiotlb_set_dma_mask(struct device *dev, u64 dma_mask)
         return 0;
 }
 EXPORT_SYMBOL_GPL(xen_swiotlb_set_dma_mask);
+
+/*
+ * Create userspace mapping for the DMA-coherent memory.
+ * This function should be called with the pages from the current domain only,
+ * passing pages mapped from other domains would lead to memory corruption.
+ */
+int
+xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+                     void *cpu_addr, dma_addr_t dma_addr, size_t size,
+                     unsigned long attrs)
+{
+#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
+        if (__generic_dma_ops(dev)->mmap)
+                return __generic_dma_ops(dev)->mmap(dev, vma, cpu_addr,
+                                                    dma_addr, size, attrs);
+#endif
+        return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mmap);
+
+/*
+ * This function should be called with the pages from the current domain only,
+ * passing pages mapped from other domains would lead to memory corruption.
+ */
+int
+xen_swiotlb_get_sgtable(struct device *dev, struct sg_table *sgt,
+                        void *cpu_addr, dma_addr_t handle, size_t size,
+                        unsigned long attrs)
+{
+#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
+        if (__generic_dma_ops(dev)->get_sgtable) {
+#if 0
+        /*
+         * This check verifies that the page belongs to the current domain and
+         * is not one mapped from another domain.
+         * This check is for debug only, and should not go to production build
+         */
+                unsigned long bfn = PHYS_PFN(dma_to_phys(dev, handle));
+                BUG_ON (!page_is_ram(bfn));
+#endif
+                return __generic_dma_ops(dev)->get_sgtable(dev, sgt, cpu_addr,
+                                                           handle, size, attrs);
+        }
+#endif
+        return dma_common_get_sgtable(dev, sgt, cpu_addr, handle, size);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_get_sgtable);