A system for protected data storage in a data memory of a computing device includes an encoder and a decoder. The encoder encrypts unencrypted data using encryption information to generate encrypted data, and stores the encrypted data and the encryption information in data memory. The decoder accesses the encrypted data and the encryption information from the data memory, and decrypts the encrypted data using the encryption information to re-generate the unencrypted data. Each time the unencrypted data is read from data memory or the unencrypted data is to be written to the data memory, the encoder re-encrypts the unencrypted data using newer encryption information to generate newer encrypted data, and replaces previous encrypted data and previous encryption information with the newer encrypted data and the newer encryption information, respectively, in the data memory. The encoder and the decoder are integrated, to operate in a single thread of execution.