STORAGE SYSTEM SUPPORTING REPLACEMENT OF CONTENT IN A STORAGE DEVICE

• US 20110179143A1
• Filed: 01/21/2010
• Published: 07/21/2011
• Est. Priority Date: 01/21/2010
• Status: Active Grant

• Current Assignee: Western Digital Israel Limited (Western Digital Corporation)
• Original Assignee: SanDisk IL Ltd. (Western Digital Corporation)
• Inventors: YAIRI, RAHAV
• Granted Patent: US 9,727,571 B2
• Time in Patent Office: Days
• US Class Current: 709/219
• CPC Class Codes: G06F 16/1734 Details of monitoring file system events, e.g. by the use of hooks, filter drivers, logs

Abstract

A file replacement system includes a storage device, a host, and a server. In a file replacement transaction one or more files that are stored in the storage device are replaced in the storage device by one or more files that are provided by the server. The storage device monitors access to the files stored therein and updates an access tracking table with segment access information that pertains to access to segments of the files. While the file replacement transaction is in progress, the storage device delivers the segment access information to the server, and, based on the segment access information and file replacement criteria, the server determines a credit to which the end-user is entitled for the replaced files. The server calculates an outstanding balance for the file replacement transaction from the credit owing to the end-user for the replaced files and from the cost of the replacement files.

Claims

1. A method of monitoring access to content in a storage device, the method comprising:

in a storage device including a memory and a memory controller for managing the memory, the memory containing an access tracking table, performing by the memory controller,

monitoring access to segments of a file stored in the memory;

updating an entry in the access tracking table, the updating being based on the monitoring and the entry being associated with the file and including segment access information for each segment of the file; and

maintaining the access tracking table for future reference, the future reference including transferring to a host device the segment access information in the entry for the entire file in response to a request pertaining to the file.

2. The method as in claim 1, wherein the future reference including:

(i) transferring to a host device the segment access information in the entry for the entire file in response to a request pertaining to the file;

(ii) receiving M (M replacement files via the host device contingent on the transferred segment access information; and

(iii) replacing the file in the memory by the M replacement files.

3. The method as in claim 1, wherein the request is to replace the file based on file replacement criteria, and wherein the file is replaced if the segment access information satisfies a criterion of the replacement criteria and/or if the host device delivers to the storage device a server command to replace the file.

4. The method as in claim 1, wherein transferring the segment access information to the host device includes transferring identity information to facilitate identification of the file and/or storage device by a server.

5. The method as in claim 4, wherein transferring the segment access information to the host device includes encrypting the identity information, or the segment access information, or both types of information.

6. The method as in claim 1, further comprising:

based on the segment access information transferred to the host device and on file replacement criteria, (i) receiving M (M≧

1) replacement files from a server via the host device, and (ii) replacing the file in the memory with the M replacement files.

7. The method as in claim 6, wherein receiving the M replacement files includes decrypting the M replacement files if the M replacement files are encrypted by the server.

8. The method as in claim 6, wherein replacing the file with the M replacement files includes limiting access to the file rather than deleting it.

9. The method as in claim 6, wherein replacing the file with the M replacement files is performed if the segment access information in the access tracking table does not change or changes only within an allowed margin from the time the segment access information is transferred to the host device until the time the M replacement files are received.

10. The method as in claim 6, wherein transferring the segment access information to the host device includes temporarily prohibiting access to the file until a response is received from the server.

11. The method as in claim 10, wherein the response from the server is any one of:

(1) transfer of the M replacement files, and (2) transfer of a message that the file is unreplaceable.

12. The method as in claim 1, wherein the segment access information pertains to any one of a number of times the file was read in its entirety, and a number of times each segment of the file was read.

13. A storage device comprising:

a memory containing an access tracking table;

a memory controller for managing the memory,

wherein the memory controller is configured,

to monitor access to segments of a file stored in the memory;

to update an entry in the access tracking table based on the monitoring, wherein the entry is associated with the file and includes segment access information for each segment of the file; and

to maintain the access tracking table for future reference, the future reference including transferring to a host device the segment access information in the entry for the entire file in response to a request pertaining to the file.

14. The storage device as in claim 13, wherein the request is to replace the file based on file replacement criteria, and wherein the file is replaced if the segment access information satisfies a criterion of the replacement criteria and/or if the host device delivers to the storage device a server command to replace the file.

15. The storage device as in claim 13, wherein the memory controller transfers identity information with the segment access information to facilitate identification of the file and/or storage device by a server.

16. The storage device as in claim 13, wherein the memory controller receives M (M≧

1) replacement files from a server via the host device contingent on the segment access information transferred to the host device and on file replacement criteria, and replaces the file in the memory with the M replacement files.

17. The storage device as in claim 16, wherein the memory controller replaces the file with the M replacement files if the segment access information in the access tracking table does not change or if it changes only within an allowed margin from the time the segment access information is transferred to the host device until the time the M replacement files are received.

18. The storage device as in claim 16, wherein the memory controller temporarily prohibits access to the file from the time it transfers the segment access information to the host device until a response is received from the server.

19. A method of replacing content in a storage device, the method comprising:

in a server including file replacement criteria and a processor, performing by the processor,

receiving segment access information from a host device regarding access to segments of a file stored in a storage device operating with the host device, and, based on the received segment access information and the file replacement criteria,

receiving selection data from the host device regarding selection of M (M≧

1) replacement files; and

transferring the M replacement files to the host device for replacing the file in the storage device.

20. A server comprising:

file replacement criteria for replacing a file in a storage device operating with a host device; and

a processor for applying the file replacement criteria,

wherein the processor is configured,

to receive segment access information from the storage device, via the host device, regarding access to segments of the file and, based on the received segment access information and the file replacement criteria,

to receive selection data from the host device regarding selection of M (M≧

1) replacement files; and

to transfer the M replacement files to the host device for replacing the file in the storage device.

21. A method of replacing content in a storage device, the method comprising:

performing by a host device,

receiving a user input regarding replacement of a file in a storage device, and in response to the user input,

requesting segment access information from the storage device regarding access to segments of the file and, in response to the request,

receiving the segment access information from the storage device;

transferring the segment access information to a server and, based on the segment access information and file replacement criteria,

receiving M (M≧

1) replacement files from the server; and

transferring the M replacement files to the storage device for replacing the file in the storage device.