Maintaining versions of data in solid state memory

• US 9,778,873 B2
• Filed: 01/18/2017
• Issued: 10/03/2017
• Est. Priority Date: 06/12/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Kandiraju, Gokul B., Franke, Hubertus, Craft, David
• Primary Examiner(s): Bertram, Ryan
• Assistant Examiner(s): CHAN, TRACY C
• Application Number:
  US15/408,521
• Publication Number:
  US 20170123708A1
• Time in Patent Office: 258 Days
• Field of Search: None
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/10 Address translation
• CPC Class Codes: G06F 12/1009 using page tables, e.g. page table structures
• CPC Class Codes: G06F 16/128 Details of file system snapshots on the file-level, e.g. snapshot creation, administration, deletion use of snapshots for error detection or correction G06F11/14, G06F11/16
• CPC Class Codes: G06F 16/1873 Versioning file systems, temporal file systems, e.g. file system supporting different historic versions of files
• CPC Class Codes: G06F 2212/1008 Correctness of operation, e.g. memory ordering
• CPC Class Codes: G06F 2212/1016 Performance improvement
• CPC Class Codes: G06F 2212/202 Non-volatile memory
• CPC Class Codes: G06F 2212/2022 Flash memory
• CPC Class Codes: G06F 2212/65 Details of virtual memory and virtual address translation
• CPC Class Codes: G06F 2212/657 Virtual address space management
• CPC Class Codes: G06F 2212/7201 Logical to physical mapping or translation of blocks or pages
• CPC Class Codes: G06F 2212/7209 Validity control, e.g. using flags, time stamps or sequence numbers
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/0635 by changing the path, e.g. traffic rerouting, path reconfiguration
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0655 Vertical data movement, i.e. input-output transfer; data movement between one or more hosts and one or more storage devices
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0679 : Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: G06F 3/0688 : Non-volatile semiconductor memory arrays
• CPC Class Codes: G11C 16/10 : Programming or data input circuits
• CPC Class Codes: G11C 16/26 : Sensing or reading circuits; Data output circuits

Abstract

Various embodiments are directed to maintaining versions of data within a solid state memory. At least one request to write at least one dataset to a logical page of a solid state memory is received from a file system. At least one physical page in a data block of the solid state memory associated with the logical page is identified. A processor stores the dataset in the at least one physical page. At least one data versioning tag is associated with the at least one dataset in a data structure associated with the logical page. The data versioning tag identifies the at least one dataset as a given version of the logical page. The at least one dataset is maintained as accessible from the at least one physical page irrespective of subsequent write operations to the logical page in response to associating the at least one data versioning tag.

Claims

1. A solid state storage device for maintaining versions of data, the solid state storage device comprising:

a processor;

a solid state memory communicatively coupled to the processor; and

a flash translation layer communicatively coupled to the processor and the solid state memory, wherein the flash translation layer is configured to perform a method comprising;

receiving, from a file system, at least one request to perform a rollback operation, the at least one request comprising at least a group identifier indicating a group of logical pages from a plurality of groups of a solid state memory on which the rollback operation is to be performed, an identifier identifying at least one logical page within the group of logical pages on which the rollback operation is to be performed;

identifying a data structure associated with the at least one logical page based on at least the group identifier;

identifying, based on the identifier, a set of information within the data structure associated with the at least one logical page;

identifying, based on the set of information, a physical page of the at least one logical page associated with a previous version of the at least one logical page; and

performing the rollback operation on the logical page by updating a logical-to-physical translation table entry for the at least one logical page to point to the physical page that has been identified.

2. The solid state storage device of claim 1, wherein the at least one request further comprises a version identifier identifying a previous version of the at least one logical page that the at least one logical page is to be rolled back to.

3. The solid state storage device of claim 2, wherein identifying the physical page further comprises

identifying, based on the set of information, a physical page of the at least one logical page associated with a version identifier matching the version identifier within the rollback request.

4. The solid state storage device of claim 1, wherein the method further comprises:

updating the data structure to move an entry for the physical page to a beginning of the data structure.

5. The solid state storage device of claim 1, wherein the group identifier identifies one of data blocks, indirect blocks, and inode blocks.

6. An information processing system comprising:

a processor;

a solid state memory communicatively coupled to the processor; and

a flash translation layer communicatively coupled to the processor and the solid state memory, wherein the flash translation layer is configured to perform a method comprising;

receiving, from a file system, at least one request to perform a rollback operation, the at least one request comprising at least a group identifier indicating a group of logical pages from a plurality of groups of a solid state memory on which the rollback operation is to be performed, an identifier identifying at least one logical page within the group of logical pages on which the rollback operation is to be performed;

identifying a data structure associated with the at least one logical page based on at least the group identifier;

identifying, based on the identifier, a set of information within the data structure associated with the at least one logical page;

identifying, based on the set of information, a physical page of the at least one logical page associated with a previous version of the at least one logical page; and

performing the rollback operation on the logical page by updating a logical-to-physical translation table entry for the at least one logical page to point to the physical page that has been identified.

7. The information processing system of claim 6, wherein the at least one request further comprises a version identifier identifying a previous version of the at least one logical page that the at least one logical page is to be rolled back to.

8. The information processing system of claim 7, wherein identifying the physical page further comprises

identifying, based on the set of information, a physical page of the at least one logical page associated with a version identifier matching the version identifier within the rollback request.

9. The information processing system of claim 6, wherein the method further comprises:

updating the data structure to move an entry for the physical page to a beginning of the data structure.

10. The information processing system of claim 6, wherein the group identifier identifies one of data blocks, indirect blocks, and inode blocks.

11. A computer program product for managing data in a solid state memory supporting data versioning, the computer program product comprising a non-transitory storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method, the method comprising:

receiving, from a file system, at least one request to perform a rollback operation, the at least one request comprising at least a group identifier indicating a group of logical pages from a plurality of groups of a solid state memory on which the rollback operation is to be performed, an identifier identifying at least one logical page within the group of logical pages on which the rollback operation is to be performed;

identifying a data structure associated with the at least one logical page based on at least the group identifier;

identifying, based on the identifier, a set of information within the data structure associated with the at least one logical page;

identifying, based on the set of information, a physical page of the at least one logical page associated with a previous version of the at least one logical page; and

performing the rollback operation on the logical page by updating a logical-to-physical translation table entry for the at least one logical page to point to the physical page that has been identified.

12. The computer program product of claim 11, wherein the at least one request further comprises a version identifier identifying a previous version of the at least one logical page that the at least one logical page is to be rolled back to.

13. The computer program product of claim 12, wherein identifying the physical page further comprises

identifying, based on the set of information, a physical page of the at least one logical page associated with a version identifier matching the version identifier within the rollback request.

14. The computer program product of claim 11, wherein the method further comprises:

updating the data structure to move an entry for the physical page to a beginning of the data structure.

15. The computer program product of claim 11, wherein the group identifier identifies one of data blocks, indirect blocks, and inode blocks.