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 a987e6fb308466fb01c4e5adaca000f299f3dd57..cccf203f3c43476f31e9c5f661b8e5978bcafaae 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
@@ -73,6 +73,7 @@ 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 pixmap_ &&
            pixmap_->ScheduleOverlayPlane(widget, z_order, transform,
                                          bounds_rect, crop_rect);
@@ -178,7 +179,8 @@ GpuMemoryBufferFactoryOzoneNativeBuffer::
     ~GpuMemoryBufferFactoryOzoneNativeBuffer() {
 }
 
-bool GpuMemoryBufferFactoryOzoneNativeBuffer::CreateGpuMemoryBuffer(
+gfx::GpuMemoryBufferHandle
+GpuMemoryBufferFactoryOzoneNativeBuffer::CreateGpuMemoryBuffer(
     gfx::GpuMemoryBufferId id,
     const gfx::Size& size,
     gfx::GpuMemoryBuffer::Format format,
@@ -193,11 +195,22 @@ 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;
+  handle.type = gfx::OZONE_NATIVE_BUFFER;
+  handle.id = id;
+  if (usage == gfx::GpuMemoryBuffer::MAP) {
+    handle.handle =
+        OzonePlatform::GetInstance()->GetSurfaceFactoryOzone()->ExportDmaBuf(

[spang, 2015/07/24 22:08:25]

What's the reason to have a SurfaceFactoryOzone::ExportDmaBuf() that just calls
dup(pixmap->GetDmaBufFd())? Seems like this is just

int dmabuf_fd = pixmap->GetDmaBufFd();
if (dmabuf_fd < 0)
  // fail

dmabuf_fd = dup(dmabuf_fd);
if (dmabuf_fd < 0)
 // also fail

handle.handle = base::FileDescriptor(dmabuf_fd, true /* auto_close */);

[dshwang, 2015/07/28 15:23:12]

good point! Done.

+            surface_handle, pixmap);
+    DCHECK(handle.handle.fd > 0) << "Fail to export dma_buf.";
   }
+
   base::AutoLock lock(native_pixmap_map_lock_);
   native_pixmap_map_[GetIndex(id, client_id)] = pixmap;
-  return true;
+  return handle;
 }
 
 void GpuMemoryBufferFactoryOzoneNativeBuffer::DestroyGpuMemoryBuffer(