Device and method for integrated data management for nonvolatile buffer cache and nonvolatile storage

An information processing apparatus, comprising:

• a processor;
• and
• an integrated nonvolatile memory control subsystem,
• wherein the integrated nonvolatile memory control subsystem comprises:
• a nonvolatile buffer cache configured to maintain one or more cache blocks;
• a nonvolatile journal area configured to maintain one or more journal blocks;
• nonvolatile storage configured to maintain one or more data blocks;
• and
• an integrated memory control unit for performing a read operation, a write operation, a commit operation and a checkpoint operation on the cache blocks of the nonvolatile buffer cache and the journal blocks of the nonvolatile journal area,
• wherein the integrated memory control unit sets each of data blocks of the nonvolatile storage as one among valid state, erasable state and invalid state, depending on being cached or not, being journaled or not, and being a clean cache or not, considers data stored in a data block of the nonvolatile storage to be authentic original if the data block is of valid state or erasable state, and considers data stored in any one of cache block and journal block to be authentic original if a corresponding data block of the nonvolatile storage is of invalid state, so as to maintain an authentic original up-to-date consistent data within any one of the nonvolatile buffer cache, the nonvolatile journal area and the nonvolatile storage.

An integrated nonvolatile memory control method for a host managing a nonvolatile buffer cache configured to maintain one or more cache blocks, a nonvolatile journal area configured to maintain one or more journal blocks, and nonvolatile storage configured to maintain one or more data blocks in an integrated manner, the method comprising:

• by the host,
• setting, as valid state, a data block corresponding to data being cached from the nonvolatile storage to the nonvolatile buffer cache and then being evicted for emptying the cache block, or a data block being not yet cached;
• setting a corresponding data block in the nonvolatile storage as valid state if a cache block cached in the nonvolatile buffer cache is a dirty up-to-date cache block, not yet committed to the nonvolatile journal area;
• setting a corresponding data block in the nonvolatile storage as invalid state if a cache block having been cached but not yet been committed to the nonvolatile buffer cache was committed to the nonvolatile journal area;
• setting a corresponding data block in the nonvolatile storage as erasable state if a cache block cached in the nonvolatile buffer cache is a clean up-to-date cache block;
• and
• setting, if a data block set as erasable state was actually erased, a clean up-to-date cache block corresponding to the erased data block as a frozen dirty up-to-date cache block and setting the erased data block in the nonvolatile storage as nominal invalid state.