ozone: Implement support for CreateGpuMemoryBufferFromHandle for OzoneNativePixmap backed GMBs.

ui/ozone/platform/drm/gpu/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/drm/gpu/gbm_surface_factory.h"
 
 #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"
 #include "ui/ozone/platform/drm/gpu/drm_window.h"
 #include "ui/ozone/platform/drm/gpu/gbm_buffer.h"
 #include "ui/ozone/platform/drm/gpu/gbm_device.h"
 #include "ui/ozone/platform/drm/gpu/gbm_surfaceless.h"
 #include "ui/ozone/platform/drm/gpu/hardware_display_controller.h"
 #include "ui/ozone/platform/drm/gpu/screen_manager.h"
 #include "ui/ozone/public/native_pixmap.h"
@@ skipping 101 matching lines @@
 #endif
 
   scoped_refptr<GbmDevice> gbm = GetGbmDevice(widget);
   DCHECK(gbm);
 
   scoped_refptr<GbmBuffer> buffer =
       GbmBuffer::CreateBuffer(gbm, format, size, usage);
   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*>(
       drm_device_manager_->GetDrmDevice(widget).get());
 }
 
 }  // namespace ui