NotForReview: Implement zero/one-copy texture for ozone freon using Intel DRM

ui/ozone/platform/drm/host/drm_display_host_manager.cc

Index: ui/ozone/platform/drm/host/drm_display_host_manager.cc
diff --git a/ui/ozone/platform/drm/host/drm_display_host_manager.cc b/ui/ozone/platform/drm/host/drm_display_host_manager.cc
index 3d7b7b4f245c81d4646f4651f7f9699753fa66e9..fff3c590a8376ef6a565f8d0c6ba532bb10323bc 100644
--- a/ui/ozone/platform/drm/host/drm_display_host_manager.cc
+++ b/ui/ozone/platform/drm/host/drm_display_host_manager.cc
@@ -23,6 +23,9 @@
 #include "ui/ozone/platform/drm/host/drm_gpu_platform_support_host.h"
 #include "ui/ozone/platform/drm/host/drm_native_display_delegate.h"
 
+#include "base/command_line.h"
+#include "ui/ozone/public/ozone_switches.h"
+
 namespace ui {
 
 namespace {
@@ -129,6 +132,11 @@ DrmDisplayHostManager::DrmDisplayHostManager(
     }
     drm_devices_.insert(primary_graphics_card_path_);
 
+    int duped_handle = HANDLE_EINTR(dup(primary_drm_device_handle_->GetFD()));
+    if (duped_handle < 0)
+      LOG(FATAL) << "Failed to dup primary graphics card for renderer";
+    primary_drm_device_file_.reset(duped_handle);
+
     vgem_card_path_ = GetVgemCardPath();
     if (!vgem_card_path_.empty()) {
       int fd = HANDLE_EINTR(
@@ -156,13 +164,23 @@ DrmDisplayHostManager::DrmDisplayHostManager(
 }
 
 base::FileDescriptor DrmDisplayHostManager::DupVgemFd() {
-  if (vgem_card_path_.empty())
+  int device_fd = vgem_card_device_file_.get();
+  base::FilePath* device_path = &vgem_card_path_;
+
+  bool enable_intel_drm = base::CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kOzoneUseIntelDrm);
+  if (enable_intel_drm) {
+    device_fd = primary_drm_device_file_.get();

[dshwang, 2015/06/29 17:42:07]

When --ozone-use-intel-drm, "/dev/dri/card0" is sent to Renderer, instead of
VGEM fd. This CL didn't rename vgem_fd_ to minimize the changes.

+    device_path = &primary_graphics_card_path_;
+  }
+
+  if (device_path->empty())
     return base::FileDescriptor();
 
   int duped_handle = -1;
   {
     base::ThreadRestrictions::ScopedAllowIO allow_io;
-    duped_handle = HANDLE_EINTR(dup(vgem_card_device_file_.get()));
+    duped_handle = HANDLE_EINTR(dup(device_fd));
   }
   if (duped_handle < 0) {
     PLOG(ERROR) << "dup() failed.";