GPU: Remove a surface from the cache when its backing memory is being unmapped from the GPU's MMU.

src/core/hle/service/nvdrv/devices/nvhost_as_gpu.cpp

@@ -8,6 +8,8 @@
 #include "core/core.h"
 #include "core/hle/service/nvdrv/devices/nvhost_as_gpu.h"
 #include "core/hle/service/nvdrv/devices/nvmap.h"
+#include "video_core/renderer_base.h"
+#include "video_core/video_core.h"
 
 namespace Service::Nvidia::Devices {
 
@@ -154,6 +156,9 @@ u32 nvhost_as_gpu::UnmapBuffer(const std::vector<u8>& input, std::vector<u8>& ou
 
     ASSERT_MSG(itr != buffer_mappings.end(), "Tried to unmap invalid mapping");
 
+    // Remove this memory region from the rasterizer cache.
+    VideoCore::g_renderer->Rasterizer()->FlushAndInvalidateRegion(params.offset, itr->second.size);
+
     params.offset = gpu.memory_manager->UnmapBuffer(params.offset, itr->second.size);
 
     buffer_mappings.erase(itr->second.offset);