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

ui/ozone/gpu/gpu_memory_buffer_factory_ozone_native_buffer.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/gpu/gpu_memory_buffer_factory_ozone_native_buffer.h"
 
 #include "base/logging.h"
 #include "ui/gl/gl_image_egl.h"
 #include "ui/gl/gl_image_linux_dma_buffer.h"
 #include "ui/ozone/public/native_pixmap.h"
@@ skipping 55 matching lines @@
       return false;
     pixmap_ = pixmap;
     return true;
   }
 
   bool ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
                             int z_order,
                             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);
   }
 
  protected:
   ~GLImageOzoneNativePixmapDmaBuf() override {}
 
  private:
   scoped_refptr<NativePixmap> pixmap_;
@@ skipping 85 matching lines @@
 }  // namespace
 
 GpuMemoryBufferFactoryOzoneNativeBuffer::
     GpuMemoryBufferFactoryOzoneNativeBuffer() {
 }
 
 GpuMemoryBufferFactoryOzoneNativeBuffer::
     ~GpuMemoryBufferFactoryOzoneNativeBuffer() {
 }
 
-bool GpuMemoryBufferFactoryOzoneNativeBuffer::CreateGpuMemoryBuffer(
+gfx::GpuMemoryBufferHandle
+GpuMemoryBufferFactoryOzoneNativeBuffer::CreateGpuMemoryBuffer(
     gfx::GpuMemoryBufferId id,
     const gfx::Size& size,
     gfx::GpuMemoryBuffer::Format format,
     gfx::GpuMemoryBuffer::Usage usage,
     int client_id,
     gfx::PluginWindowHandle surface_handle) {
   scoped_refptr<NativePixmap> pixmap =
       OzonePlatform::GetInstance()
           ->GetSurfaceFactoryOzone()
           ->CreateNativePixmap(surface_handle, size, GetOzoneFormatFor(format),
                                GetOzoneUsageFor(usage));
   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(
     gfx::GpuMemoryBufferId id,
     int client_id) {
   base::AutoLock lock(native_pixmap_map_lock_);
   native_pixmap_map_.erase(GetIndex(id, client_id));
 }
 
 scoped_refptr<gfx::GLImage>
@@ skipping 40 matching lines @@
         new GLImageOzoneNativePixmapDmaBuf(size, internalformat);
     if (!image->Initialize(pixmap.get(), format)) {
       return scoped_refptr<gfx::GLImage>();
     }
     return image;
   }
   return new GLImageOzoneOverlayOnlyPassThrough(pixmap, size, internalformat);
 }
 
 }  // namespace ui