Add ability to query and allocate zero copy buffers.

ui/ozone/platform/dri/gbm_surface_factory.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/ozone/platform/dri/gbm_surface_factory.h"
 
 #include <gbm.h>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 151 matching lines @@
     gfx::AcceleratedWidget widget) {
   if (!allow_surfaceless_)
     return scoped_ptr<SurfaceOzoneEGL>();
 
   DriWindowDelegate* delegate = GetOrCreateWindowDelegate(widget);
   return scoped_ptr<SurfaceOzoneEGL>(new GbmSurfaceless(delegate));
 }
 
 scoped_refptr<ui::NativePixmap> GbmSurfaceFactory::CreateNativePixmap(
     gfx::Size size,
-    BufferFormat format) {
-  scoped_refptr<GbmBuffer> buffer = GbmBuffer::CreateBuffer(
-      drm_, device_, format, size, true);
+    BufferFormat format,
+    BufferUsage usage) {
+  if (usage == MAP)
+    return NULL;
+
+  scoped_refptr<GbmBuffer> buffer =
+      GbmBuffer::CreateBuffer(drm_, device_, format, size, true);
   if (!buffer.get())
     return NULL;
 
   scoped_refptr<GbmPixmap> pixmap(new GbmPixmap(buffer));
   if (!pixmap->Initialize(drm_))
     return NULL;
 
   return pixmap;
 }
 
@@ skipping 27 matching lines @@
                                       plane_transform,
                                       display_bounds,
                                       crop_rect));
   return true;
 }
 
 bool GbmSurfaceFactory::CanShowPrimaryPlaneAsOverlay() {
   return allow_surfaceless_;
 }
 
+bool GbmSurfaceFactory::CanCreateNativePixmap(BufferUsage usage) {
+  switch (usage) {
+    case MAP:
+      return false;
+    case SCANOUT:
+      return true;
+  }
+  NOTREACHED();
+  return false;
+}
+
 DriWindowDelegate* GbmSurfaceFactory::GetOrCreateWindowDelegate(
     gfx::AcceleratedWidget widget) {
   if (!window_manager_->HasWindowDelegate(widget)) {
     scoped_ptr<DriWindowDelegate> delegate(
         new DriWindowDelegateImpl(widget, screen_manager_));
     delegate->Initialize();
     window_manager_->AddWindowDelegate(widget, delegate.Pass());
   }
 
   return window_manager_->GetWindowDelegate(widget);
 }
 
 }  // namespace ui