MAINTENANCE OF EXO-FILE SYSTEM METADATA ON REMOVABLE STORAGE DEVICE

• US 20090327295A1
• Filed: 06/25/2008
• Published: 12/31/2009
• Est. Priority Date: 06/25/2008
• Status: Abandoned Application

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Bovee, James, Sadovsky, Vlad
• Application Number:
  US12/146,024
• Publication Number:
  US 20090327295A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/1847 specifically adapted to static storage, e.g. adapted to flash memory or SSD
• CPC Class Codes: G06F 16/907 Retrieval characterised by using metadata, e.g. metadata not derived from the content or metadata generated manually

Abstract

An interface between a host computing device and a transient storage device (TSD) eliminates the need for a full directory crawl of the storage volume on the TSD to maintain a metadata database. The metadata database is incrementally updated instead of being completely regenerated on every connection between the TSD and a highly capable host. This function helps the host device more efficiently track and maintain exo-file system metadata. Host devices discover and use this new TSD function to efficiently update the metadata database. Host devices provide parameters governing the operation of the TSD to the TSD. Cooperatively, the TSD logs addresses corresponding to storage locations of changes made to the data on the storage volume and, upon discovering a capability of the host device to update the metadata database, the TSD provides discovery to the host device regarding an availability of the metadata database and the log of addresses.

Claims

1. A method on a storage device for maintaining an exo-file system metadata database of information about data stored on a storage volume of the storage device, the method comprising

establishing a connection with a host device;

discovering a capability of the host device to update the metadata database;

logging addresses corresponding to storage locations of changes made to the data on the storage volume; and

providing discovery to the host device regarding an availability of the metadata database and a log of addresses corresponding to storage locations of changes made to the data on the storage volume.

2. The method of claim 1, further comprising authenticating the host device to authorize an update to the storage volume and the metadata database.

3. The method of claim 1 further comprising

receiving changes to the metadata database from the host device based upon the log of addresses;

and

reading, writing, and modifying the metadata database pursuant to the received changes.

4. The method of claim 3, further comprising clearing the log of addresses after completion of the reading, writing, and modifying operation.

5. The method of claim 3, wherein

the providing discovery operation further comprises providing a subset of the log of addresses pursuant to direction of the host device;

and

the method further comprises clearing the subset of the log of addresses after completion of the reading, writing, and modifying operation.

6. The method of claim 1 further comprising

receiving changes to the data on the storage volume from the host device;

and

reading, writing, and modifying the data on the storage volume pursuant to the received changes.

7. A method on a host computer device connected with a storage device for maintaining an exo-file system metadata database of information about data stored on a storage volume of the storage device, the method comprising

establishing a connection with a storage device;

providing discovery to the storage device regarding a capability to update the metadata database;

receiving discovery from the storage device about an availability of the metadata database and a log of addresses corresponding to storage locations of changes made to the data on the storage volume;

reading the log of addresses to identify the storage locations of changed data on the storage volume;

extracting metadata from changed data found at the identified storage locations; and

instructing the storage device to update the metadata database with the extracted metadata.

8. The method of claim 7 further comprising receiving an authentication confirmation from the storage device authorizing the update to the metadata database.

9. The method of claim 7 further comprising instructing the storage device to clear the log of addresses after completion of the reading, writing, and modifying operation.

10. The method of claim 7, wherein

the reading operation further comprises filtering the log of addresses to identify a subset of the storage locations of changed data;

and

the extracting operation further comprises extracting metadata from a subset of the changed data corresponding to the subset of the storage locations.

11. The method of claim 10 further comprising instructing the storage device to clear a subset of the log of addresses corresponding to the subset of the storage locations after the storage device completes updating the metadata database.

12. The method of claim 7 further comprising

copying the metadata database from the storage device;

and

storing the copied metadata database on the host computer system.

13. The method of claim 7 further comprising instructing the storage device to write changes to the data on the storage volume.

14. A computer-readable medium storing computer-executable instructions for performing a computer process on a host computer device connected with a storage device to maintain an exo-file system metadata database of information about data stored on a storage volume of the storage device, wherein the instructions comprise operations to

establish a connection with a storage device;

provide discovery to the storage device regarding a capability to update the metadata database;

receive discovery from the storage device about an availability of the metadata database and a log of addresses corresponding to storage locations of changes made to the data on the storage volume;

read the log of addresses to identify the storage locations of changed data on the storage volume;

extract metadata from changed data found at the identified storage locations; and

instruct the storage device to update the metadata database with the extracted metadata.

15. The computer-readable medium of claim 14, wherein the instructions further comprise operations to receive an authentication confirmation from the storage device authorizing the update to the metadata database.

16. The computer-readable medium of claim 14, wherein the instructions further comprise operations to instruct the storage device to clear the log of addresses after completion of the reading, writing, and modifying operation.

17. The computer-readable medium of claim 14, wherein

the reading operation further comprises operations to filter the log of addresses to identify a subset of the storage locations of changed data;

and

the extracting operation further comprises operations to extract metadata from a subset of the changed data corresponding to the subset of the storage locations.

18. The computer-readable medium of claim 17, wherein the instructions further comprise operations to instruct the storage device to clear a subset of the log of addresses corresponding to the subset of the storage locations after the storage device completes updating the metadata database.

19. The computer-readable medium of claim 14, wherein the instructions further comprise operations to

copy the metadata database from the storage device;

and

store the copied metadata database on the host computer system.

20. The computer-readable medium of claim 14, wherein the instructions further comprise operations to instruct the storage device to write changes to the data on the storage volume.