ozone: Implement support for CreateGpuMemoryBufferFromHandle for OzoneNativePixmap backed GMBs.

ui/ozone/platform/drm/gpu/gbm_surface_factory.cc

Index: ui/ozone/platform/drm/gpu/gbm_surface_factory.cc
diff --git a/ui/ozone/platform/drm/gpu/gbm_surface_factory.cc b/ui/ozone/platform/drm/gpu/gbm_surface_factory.cc
index 060f7be7a90044edaf2b249d583bcdef49796f1b..97118659019b7181d7bd723f59c1cbafca37abff 100644
--- a/ui/ozone/platform/drm/gpu/gbm_surface_factory.cc
+++ b/ui/ozone/platform/drm/gpu/gbm_surface_factory.cc
@@ -7,6 +7,7 @@
 #include <gbm.h>
 
 #include "base/files/file_path.h"
+#include "base/posix/eintr_wrapper.h"
 #include "third_party/khronos/EGL/egl.h"
 #include "ui/ozone/common/egl_util.h"
 #include "ui/ozone/platform/drm/gpu/drm_device_manager.h"
@@ -128,13 +129,26 @@ scoped_refptr<ui::NativePixmap> GbmSurfaceFactory::CreateNativePixmap(
   if (!buffer.get())
     return nullptr;
 
-  scoped_refptr<GbmPixmap> pixmap(new GbmPixmap(buffer, this));
-  if (!pixmap->Initialize())
+  scoped_refptr<GbmPixmap> pixmap(new GbmPixmap(this));
+  if (!pixmap->InitializeFromBuffer(buffer))
     return nullptr;
 
   return pixmap;
 }
 
+scoped_refptr<ui::NativePixmap> GbmSurfaceFactory::CreateNativePixmapFromHandle(
+    const gfx::NativePixmapHandle& handle) {
+  int dmabuf_fd = HANDLE_EINTR(dup(handle.fd.fd));

[piman, 2015/10/08 23:24:36]

Why do we need to dup here, and if so, where is the close for the handle that is
passed as a parameter? I would assume
GMBFactory::CreateGpuMemoryBufferFromHandle would take ownership of the handle,
and if not, it needs to close it. The IPC system will not.

[reveman, 2015/10/09 12:47:02]

Good call. We shouldn't dup it here. This just happened to work as we were not
dup-ing the fd returned to the browser so these two errors were cancelling each
other out. Fixed this in latest patch by not calling dup() here and instead
using ExportHandle() in
GpuMemoryBufferFactoryOzoneNativePixmap::CreateGpuMemoryBufferFromHandle. I also
added a comment to the SurfaceFactoryOzone interface to make it clear that this
function takes ownership of the handle.

+  if (dmabuf_fd < 0) {
+    PLOG(ERROR) << "dup";
+    return nullptr;
+  }
+
+  scoped_refptr<GbmPixmap> pixmap(new GbmPixmap(this));
+  pixmap->Initialize(dmabuf_fd, handle.stride);
+  return pixmap;
+}
+
 scoped_refptr<GbmDevice> GbmSurfaceFactory::GetGbmDevice(
     gfx::AcceleratedWidget widget) {
   return static_cast<GbmDevice*>(