void IOBuf::freeInternalBuf(void* /* buf */, void* userData) noexcept {
  auto storage = static_cast<HeapStorage*>(userData);
  releaseStorage(storage, kDataInUse);
}
void IOBuf::freeInternalBuf(void*  , void* userData) noexcept {
  auto storage = static_cast<HeapStorage*>(userData);
  releaseStorage(storage, kDataInUse);
}