gpu/drm/ttm: use copy_highpage

Use copy_highpage() to copy from one page to another.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/ttm/ttm_tt.c

@@ -290,8 +290,6 @@ int ttm_tt_swapin(struct ttm_tt *ttm)
 	struct file *swap_storage;
 	struct page *from_page;
 	struct page *to_page;
-	void *from_virtual;
-	void *to_virtual;
 	int i;
 	int ret = -ENOMEM;
 
@@ -311,11 +309,7 @@ int ttm_tt_swapin(struct ttm_tt *ttm)
 			goto out_err;
 
 		preempt_disable();
-		from_virtual = kmap_atomic(from_page);
-		to_virtual = kmap_atomic(to_page);
-		memcpy(to_virtual, from_virtual, PAGE_SIZE);
-		kunmap_atomic(to_virtual);
-		kunmap_atomic(from_virtual);
+		copy_highpage(to_page, from_page);
 		preempt_enable();
 		page_cache_release(from_page);
 	}
@@ -336,8 +330,6 @@ int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
 	struct file *swap_storage;
 	struct page *from_page;
 	struct page *to_page;
-	void *from_virtual;
-	void *to_virtual;
 	int i;
 	int ret = -ENOMEM;
 
@@ -367,11 +359,7 @@ int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
 			goto out_err;
 		}
 		preempt_disable();
-		from_virtual = kmap_atomic(from_page);
-		to_virtual = kmap_atomic(to_page);
-		memcpy(to_virtual, from_virtual, PAGE_SIZE);
-		kunmap_atomic(to_virtual);
-		kunmap_atomic(from_virtual);
+		copy_highpage(to_page, from_page);
 		preempt_enable();
 		set_page_dirty(to_page);
 		mark_page_accessed(to_page);