234   auto source_fd = ChooseSourceFD(operation, error);  in PerformSourceCopyOperation()  local
235   if (*error != ErrorCode::kSuccess || source_fd == nullptr) {  in PerformSourceCopyOperation()
250       optimized, std::move(writer), source_fd);  in PerformSourceCopyOperation()
257   FileDescriptorPtr source_fd = ChooseSourceFD(operation, error);  in PerformDiffOperation()  local
258   TEST_AND_RETURN_FALSE(source_fd != nullptr);  in PerformDiffOperation()
262       operation, std::move(writer), source_fd, data, count);  in PerformDiffOperation()
298                                          const FileDescriptorPtr source_fd,  in ValidateSourceHash()  argument
303       source_fd, operation.src_extents(), block_size, &source_hash));  in ValidateSourceHash()
304   return ValidateSourceHash(source_hash, operation, source_fd, error);  in ValidateSourceHash()
309                                          const FileDescriptorPtr source_fd,  in ValidateSourceHash()  argument
339     LogMountHistory(source_fd);  in ValidateSourceHash()