GraphicsBuffer can be used as a constant buffer (uniform buffer).
If you use this target, you can use the GraphicsBuffer as a parameter to Shader.SetConstantBuffer and Material.SetConstantBuffer.
If you also need the buffer to be bound as a structured buffer, you must add the GraphicsBuffer.Target.Structured flag. Some renderers (such as DX11) do not support binding buffers as both constant and structured buffers.