ozone: Implement zero/one-copy texture for Ozone GBM.

ui/ozone/gpu/gpu_memory_buffer_factory_ozone_native_buffer.cc

Index: ui/ozone/gpu/gpu_memory_buffer_factory_ozone_native_buffer.cc
diff --git a/ui/ozone/gpu/gpu_memory_buffer_factory_ozone_native_buffer.cc b/ui/ozone/gpu/gpu_memory_buffer_factory_ozone_native_buffer.cc
index 51ff149976c75b71dda485ed30d42ae6305df825..7b42b11a15faeb86f8b36e205d5413bd6eea6e4b 100644
--- a/ui/ozone/gpu/gpu_memory_buffer_factory_ozone_native_buffer.cc
+++ b/ui/ozone/gpu/gpu_memory_buffer_factory_ozone_native_buffer.cc
@@ -72,6 +72,7 @@ class GLImageOzoneNativePixmapDmaBuf : public gfx::GLImageLinuxDMABuffer {
                             gfx::OverlayTransform transform,
                             const gfx::Rect& bounds_rect,
                             const gfx::RectF& crop_rect) override {
+    DCHECK_EQ(pixmap_->GetBufferUsage(), NativePixmap::SCANOUT);
     return SurfaceFactoryOzone::GetInstance()->ScheduleOverlayPlane(
         widget, z_order, transform, pixmap_, bounds_rect, crop_rect);
   }
@@ -133,7 +134,8 @@ GpuMemoryBufferFactoryOzoneNativeBuffer::
     ~GpuMemoryBufferFactoryOzoneNativeBuffer() {
 }
 
-bool GpuMemoryBufferFactoryOzoneNativeBuffer::CreateGpuMemoryBuffer(
+gfx::GpuMemoryBufferHandle
+GpuMemoryBufferFactoryOzoneNativeBuffer::CreateGpuMemoryBuffer(
     gfx::GpuMemoryBufferId id,
     const gfx::Size& size,
     gfx::GpuMemoryBuffer::Format format,
@@ -147,11 +149,19 @@ bool GpuMemoryBufferFactoryOzoneNativeBuffer::CreateGpuMemoryBuffer(
   if (!pixmap.get()) {
     LOG(ERROR) << "Failed to create pixmap " << size.width() << "x"
                << size.height() << " format " << format << ", usage " << usage;
-    return false;
+    return gfx::GpuMemoryBufferHandle();
   }
+
+  gfx::GpuMemoryBufferHandle handle =
+      SurfaceFactoryOzone::GetInstance()->ExportGpuMemoryBufferHandle(

[vignatti (out of this project), 2015/05/14 19:20:04]

Am I wrong or the concept here is the opposite? GPU process is *importing* a
device handle through vgem, which was opened in the Renderer process?
ImportGpuMemoryBufferHandle therefore makes more sense.

[dshwang, 2015/06/25 10:59:56]

GPU process create gbm bo and *exporting* the dma_buf, and then Renderer is
*importing* the dam_buf as vgem bo.

+          surface_handle, pixmap);
+  if (handle.type == gfx::EMPTY_BUFFER)
+    return gfx::GpuMemoryBufferHandle();
+  handle.id = id;
+
   base::AutoLock lock(native_pixmap_map_lock_);
   native_pixmap_map_[GetIndex(id, client_id)] = pixmap;
-  return true;
+  return handle;
 }
 
 void GpuMemoryBufferFactoryOzoneNativeBuffer::DestroyGpuMemoryBuffer(