1 files changed, 52 insertions, 33 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 1f730b3f18e5..2ebbae6067ab 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -255,6 +255,54 @@ static int ttm_copy_io_page(void *dst, void *src, unsigned long page)
         return 0;
 }
 
+#ifdef CONFIG_X86
+#define __ttm_kmap_atomic_prot(__page, __prot) kmap_atomic_prot(__page, __prot)
+#define __ttm_kunmap_atomic(__addr) kunmap_atomic(__addr)
+#else
+#define __ttm_kmap_atomic_prot(__page, __prot) vmap(&__page, 1, 0,  __prot)
+#define __ttm_kunmap_atomic(__addr) vunmap(__addr)
+#endif
+
+
+/**
+ * ttm_kmap_atomic_prot - Efficient kernel map of a single page with
+ * specified page protection.
+ *
+ * @page: The page to map.
+ * @prot: The page protection.
+ *
+ * This function maps a TTM page using the kmap_atomic api if available,
+ * otherwise falls back to vmap. The user must make sure that the
+ * specified page does not have an aliased mapping with a different caching
+ * policy unless the architecture explicitly allows it. Also mapping and
+ * unmapping using this api must be correctly nested. Unmapping should
+ * occur in the reverse order of mapping.
+ */
+void *ttm_kmap_atomic_prot(struct page *page, pgprot_t prot)
+{
+        if (pgprot_val(prot) == pgprot_val(PAGE_KERNEL))
+                return kmap_atomic(page);
+        else
+                return __ttm_kmap_atomic_prot(page, prot);
+}
+EXPORT_SYMBOL(ttm_kmap_atomic_prot);
+
+/**
+ * ttm_kunmap_atomic_prot - Unmap a page that was mapped using
+ * ttm_kmap_atomic_prot.
+ *
+ * @addr: The virtual address from the map.
+ * @prot: The page protection.
+ */
+void ttm_kunmap_atomic_prot(void *addr, pgprot_t prot)
+{
+        if (pgprot_val(prot) == pgprot_val(PAGE_KERNEL))
+                kunmap_atomic(addr);
+        else
+                __ttm_kunmap_atomic(addr);
+}
+EXPORT_SYMBOL(ttm_kunmap_atomic_prot);
+
 static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
                                 unsigned long page,
                                 pgprot_t prot)
@@ -266,28 +314,13 @@ static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
                 return -ENOMEM;
 
         src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
-
-#ifdef CONFIG_X86
-        dst = kmap_atomic_prot(d, prot);
-#else
-        if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
-                dst = vmap(&d, 1, 0, prot);
-        else
-                dst = kmap(d);
-#endif
+        dst = ttm_kmap_atomic_prot(d, prot);
         if (!dst)
                 return -ENOMEM;
 
         memcpy_fromio(dst, src, PAGE_SIZE);
 
-#ifdef CONFIG_X86
-        kunmap_atomic(dst);
-#else
-        if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
-                vunmap(dst);
-        else
-                kunmap(d);
-#endif
+        ttm_kunmap_atomic_prot(dst, prot);
 
         return 0;
 }
@@ -303,27 +336,13 @@ static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
                 return -ENOMEM;
 
         dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
-#ifdef CONFIG_X86
-        src = kmap_atomic_prot(s, prot);
-#else
-        if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
-                src = vmap(&s, 1, 0, prot);
-        else
-                src = kmap(s);
-#endif
+        src = ttm_kmap_atomic_prot(s, prot);
         if (!src)
                 return -ENOMEM;
 
         memcpy_toio(dst, src, PAGE_SIZE);
 
-#ifdef CONFIG_X86
-        kunmap_atomic(src);
-#else
-        if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
-                vunmap(src);
-        else
-                kunmap(s);
-#endif
+        ttm_kunmap_atomic_prot(src, prot);
 
         return 0;
 }