Add multi-process GpuMemoryBuffer framework.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index 4f719e393a5ed53f7afca5c9b2dd57c1d4c53628..aa5b56543f8c061e4a315f02247eb85f1b25f8fa 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -44,6 +44,7 @@
 #include "content/common/dom_storage/dom_storage_messages.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
 #include "content/common/gpu/client/gpu_channel_host.h"
+#include "content/common/gpu/client/gpu_memory_buffer_impl.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/common/resource_messages.h"
 #include "content/common/view_messages.h"
@@ -1052,6 +1053,47 @@ void RenderThreadImpl::DeleteImage(int32 image_id, int32 sync_point) {
   NOTREACHED();
 }
 
+scoped_ptr<gfx::GpuMemoryBuffer> RenderThreadImpl::AllocateGpuMemoryBuffer(
+    size_t width,
+    size_t height,
+    unsigned internalformat) {
+  if (!GpuMemoryBufferImpl::IsFormatValid(internalformat))
+    return scoped_ptr<gfx::GpuMemoryBuffer>();
+
+  size_t size = width * height *
+      GpuMemoryBufferImpl::BytesPerPixel(internalformat);
+  if (size > static_cast<size_t>(std::numeric_limits<int>::max()))
+    return scoped_ptr<gfx::GpuMemoryBuffer>();
+
+  gfx::GpuMemoryBufferHandle handle;
+  bool success;
+  IPC::Message* message =
+      new ChildProcessHostMsg_SyncAllocateGpuMemoryBuffer(size, &handle);
+
+  // Allow calling this from the compositor thread.
+  if (base::MessageLoop::current() == message_loop())
+    success = ChildThread::Send(message);
+  else
+    success = sync_message_filter()->Send(message);
+
+  if (!success)
+    return scoped_ptr<gfx::GpuMemoryBuffer>();
+
+  // Currently, shared memory is the only supported buffer type.
+  if (handle.type != gfx::SHARED_MEMORY_BUFFER)
+    return scoped_ptr<gfx::GpuMemoryBuffer>();
+
+  if (!base::SharedMemory::IsHandleValid(handle.handle))
+    return scoped_ptr<gfx::GpuMemoryBuffer>();
+
+  return make_scoped_ptr<gfx::GpuMemoryBuffer>(
+      new GpuMemoryBufferImpl(
+          make_scoped_ptr(new base::SharedMemory(handle.handle, false)),
+          width,
+          height,
+          internalformat));
+}
+
 void RenderThreadImpl::DoNotSuspendWebKitSharedTimer() {
   suspend_webkit_shared_timer_ = false;
 }