Merge branch 'stable/for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel...

[sfrench/cifs-2.6.git] / drivers / xen / swiotlb-xen.c

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index f8afc6dcc29f2769694308092a4b543e5e0bed49..e8cef1ad0fe31e0139903399d70730c7eafdc399 100644 (file)
--- 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);