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

content/common/gpu/gpu_memory_buffer_factory_ozone_native_pixmap.cc

Index: content/common/gpu/gpu_memory_buffer_factory_ozone_native_pixmap.cc
diff --git a/content/common/gpu/gpu_memory_buffer_factory_ozone_native_pixmap.cc b/content/common/gpu/gpu_memory_buffer_factory_ozone_native_pixmap.cc
index d3e0576124a9be60c8f6e67f2dddfbc0ca0f63d8..990d0e2dc9d3f15f6482d394d7aac5a334c1e88d 100644
--- a/content/common/gpu/gpu_memory_buffer_factory_ozone_native_pixmap.cc
+++ b/content/common/gpu/gpu_memory_buffer_factory_ozone_native_pixmap.cc
@@ -4,6 +4,7 @@
 
 #include "content/common/gpu/gpu_memory_buffer_factory_ozone_native_pixmap.h"
 
+#include "base/posix/eintr_wrapper.h"
 #include "ui/gl/gl_image_ozone_native_pixmap.h"
 #include "ui/ozone/public/client_native_pixmap_factory.h"
 #include "ui/ozone/public/ozone_platform.h"
@@ -24,6 +25,18 @@ void GetSupportedConfigurations(
   }
 }
 
+bool ShareToClientProcess(int fd, base::FileDescriptor* new_handle) {
+  int duped_handle = HANDLE_EINTR(dup(fd));
+  if (duped_handle < 0) {
+    DPLOG(ERROR) << "dup() failed.";
+    *new_handle = base::FileDescriptor();
+    return false;
+  }
+
+  *new_handle = base::FileDescriptor(duped_handle, true);
+  return true;
+}
+
 }  // namespace
 
 GpuMemoryBufferFactoryOzoneNativePixmap::
@@ -79,6 +92,14 @@ GpuMemoryBufferFactoryOzoneNativePixmap::CreateGpuMemoryBuffer(
   gfx::GpuMemoryBufferHandle handle;
   handle.type = gfx::OZONE_NATIVE_PIXMAP;
   handle.id = id;
+  if (usage == gfx::BufferUsage::MAP) {
+    base::FileDescriptor dma_buf;
+    if (!ShareToClientProcess(pixmap->GetDmaBufFd(), &dma_buf)) {
+      DLOG(ERROR) << "Fail to duplicate a DMA-BUF file descriptor";
+      return gfx::GpuMemoryBufferHandle();
+    }
+    handle.handle = dma_buf;
+  }
   return handle;
 }