gpu: Remove Create/DeleteImage IPC by adding an X11_PIXMAP_BUFFER GpuMemoryBuffer type.

content/common/gpu/gpu_command_buffer_stub.cc

Index: content/common/gpu/gpu_command_buffer_stub.cc
diff --git a/content/common/gpu/gpu_command_buffer_stub.cc b/content/common/gpu/gpu_command_buffer_stub.cc
index 3795fa7acf1e09a2c7472093ce1e3d2967cee6c1..026184c96230cbf856d72d4f51360fb4999427e5 100644
--- a/content/common/gpu/gpu_command_buffer_stub.cc
+++ b/content/common/gpu/gpu_command_buffer_stub.cc
@@ -14,6 +14,7 @@
 #include "content/common/gpu/gpu_channel.h"
 #include "content/common/gpu/gpu_channel_manager.h"
 #include "content/common/gpu/gpu_command_buffer_stub.h"
+#include "content/common/gpu/gpu_memory_buffer_factory.h"
 #include "content/common/gpu/gpu_memory_manager.h"
 #include "content/common/gpu/gpu_memory_tracking.h"
 #include "content/common/gpu/gpu_messages.h"
@@ -928,13 +929,19 @@ void GpuCommandBufferStub::OnSetClientHasMemoryAllocationChangedCallback(
 
 void GpuCommandBufferStub::OnRegisterGpuMemoryBuffer(
     int32 id,
-    gfx::GpuMemoryBufferHandle gpu_memory_buffer,
+    gfx::GpuMemoryBufferHandle handle,
     uint32 width,
     uint32 height,
     uint32 internalformat) {
   TRACE_EVENT0("gpu", "GpuCommandBufferStub::OnRegisterGpuMemoryBuffer");
+
+  // Verify that renderer is not trying to use a buffer it doesn't own.
+  if (!GpuMemoryBufferFactory::RequestAccessToGpuMemoryBuffer(
+          handle, channel()->client_id())) {
+    LOG(ERROR) << "Access to GPU memory buffer by renderer denied.";
+    return;
+  }

[piman, 2014/06/17 23:38:11]

Because XID is a field of handle, if you grab the XID here from the map, then
you don't need to access that map from ui/gl at all, so you don't need to pass
state via a global (since you can simply stash the map on the
GpuChannelManager). fewer interfaces, less code.

[reveman, 2014/06/18 22:06:28]

That works in the case of X11 pixmaps and XIDs but it would be a different story
with surface textures for example. I'm not sure it's a good idea to turn the
handle into some arbitrary struct for passing data between the stub and the
GLImage system as it's supposed to represent a serializable reference to a gpu
memory buffer. Maybe we need some new type of in-process gpu memory buffer
handle that can be used here..

[piman, 2014/06/18 22:14:36]

If the GpuMemoryBufferHandle doesn't include the native handle, then I'm not
sure about the parts of this CL that pass the XID through it for the CreateImage
path.

Either way, if we need a data structure to do the GpuMemoryBufferHandle->native
handle mapping, that can be owned by the GpuChannelManager and passed explicitly
to GLImage::CreateGLImageForGpuMemoryBuffer. No need for globals for that.

 #if defined(OS_ANDROID)
-  // Verify that renderer is not trying to use a surface texture it doesn't own.
   if (gpu_memory_buffer.type == gfx::SURFACE_TEXTURE_BUFFER &&
       gpu_memory_buffer.surface_texture_id.secondary_id !=
           channel()->client_id()) {
@@ -942,9 +949,10 @@ void GpuCommandBufferStub::OnRegisterGpuMemoryBuffer(
     return;
   }
 #endif
+
   if (gpu_control_service_) {
     gpu_control_service_->RegisterGpuMemoryBuffer(
-        id, gpu_memory_buffer, width, height, internalformat);
+        id, handle, width, height, internalformat);
   }
 }