Reducing connection time for mass storage class peripheral by internally prefetching file data into local cache in response to connection to host

• US 7,912,994 B2
• Filed: 01/27/2006
• Issued: 03/22/2011
• Est. Priority Date: 01/27/2006
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Cornwell, Michael J., Dudte, Christopher P.
• Primary Examiner(s): PEYTON, TAMMARA R
• Application Number:
  US11/342,126
• Publication Number:
  US 20070180153A1
• Time in Patent Office: 1,880 Days
• Field of Search: 710/1, 710 8- 10, 710/14, 710/38, 710/74, 710/310, 710/13, 713/1, 713/2, 709/217, 709/224, 711/137, 711/103, 711/127, 345/745
• US Class Current: 710/14
• CPC Class Codes: G06F 16/172 Caching, prefetching or hoarding of files
• CPC Class Codes: G06F 3/0611 in relation to response time
• 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 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

Techniques for reducing mount time for a peripheral device connected to an external host device are presented. In some implementations, when a connection is detected, file system data is pre-fetched before a request for such data is sent by the external host device. This allows faster access to the file system data used for initiating read/write communications. In other implementations, in response to a data access command from the external host device, a reply message is delayed from the peripheral device to prevent data access command failures. This delayed response prevents the external host device from pausing before attempting subsequent communication requests.

Claims

1. A method for establishing communications involving a peripheral device, the method comprising:

establishing a connection between the peripheral device and a host device; and

pre-fetching, at the peripheral device, file system data from one or more storage media accessible by the peripheral device into a memory of the peripheral device in response to the established connection, the file system data pre-fetched prior to receiving a request for the file system data from the host device, wherein the file system data is adapted for providing at least one of read access or write access to the one or more storage media.

2. The method of claim 1 wherein pre-fetching the file system data comprises loading the file system data into a local cache.

3. The method of claim 1 further comprising switching the peripheral device from a first mode into a second mode in response to the established connection, wherein the first mode is associated with playback of multimedia files selected from a group consisting of a music file, a video file, a picture file, and a document file on the peripheral device, and the second mode is associated with file transfer access between the peripheral device and the host device.

4. The method of claim 3 wherein the file system data comprises data for enabling access to files stored on the one or more storage media.

5. The method of claim 3 wherein pre-fetching the file system data from the one or more storage media is performed concurrently with switching the peripheral device from the first mode into the second mode.

6. The method of claim 1 wherein the peripheral device is selected from a group consisting of a peripheral disk drive device, a logical disk drive, a removable storage device, a portable device that includes a storage media, and a mass storage device.

7. The method of claim 1 wherein the file system data comprises information for enabling access to data on the one or more storage media.

8. The method of claim 7 wherein the file system data comprises directory data.

27. The method of claim 1, wherein the file system data comprises at least one of hierarchical file system (HFS) data, new technology file system (NTFS) data, second extended file system (ext2) data or universal disk format (UDF).

9. A method for establishing communications involving a peripheral device, the method comprising:

establishing a connection between a peripheral device and a host device;

receiving a data access message from the host device in response to establishing the connection between the peripheral device and the host device;

switching the peripheral device from a first mode into a second mode in response to the established connection; and

delaying sending, from the peripheral device, a response to the data access message until the peripheral device completes the switch from a first mode into a second mode.

10. The method of claim 9 wherein delaying sending the response to the data access message further comprises delaying sending the response until buffers are cleared in the peripheral device.

11. The method of claim 9 wherein the first mode is associated with playback of a media file selected from a group consisting of a music file, a video file, a picture file, a document file, and a multimedia file on the peripheral device, and the second mode is associated with file transfer access between the peripheral device and the host device.

12. The method of claim 9 wherein the peripheral device is selected from a group consisting of a peripheral disk drive device, a logical disk drive, a removable storage device, a portable device that includes a storage media, and a mass storage device.

13. The method of claim 9 further comprising:

pre-fetching, at the peripheral device, file system data from one or more storage devices accessible by the peripheral device into a memory of the peripheral device in response to the established connection, the file system data retrieved prior to receiving a request for the file system data from the host device, wherein the file system data is adapted for providing at least one of read or write access to the one or more storage devices.

14. The method of claim 13, wherein pre-fetching the file system data from the one or more storage device accessible by the peripheral device into the memory of the peripheral device in response to the established connection is performed in parallel with switching the peripheral device from the first mode into the second mode.

28. The method of claim 13, wherein the file system data comprises at least one of hierarchical file system (HFS) data, new technology file system (NTFS) data, second extended file system (ext2) data or universal disk format (UDF).

32. The method of claim 9, wherein the data access message from the host device indicates a request for the host device to have read or write access to data stored by the peripheral device;

and

wherein the peripheral device is not configured to provide the host device with read or write access to the data when operating in the first mode, and wherein the peripheral device is configured to provide the host device with read or write access to the data when operating in the second mode.

15. A machine readable storage medium storing instructions operable to cause data processing apparatus to:

establish a connection between a peripheral device and a host device; and

pre-fetch file system data from one or more storage media accessible by the peripheral device into a memory of the peripheral device in response to the established-connection, the file system data pre-fetched prior to receiving a request for the file system data from the host device, wherein the file system data is adapted for providing at least one of read or write access to the one or more storage media.

16. The machine readable storage medium of claim 15 wherein pre-fetching the file system data further comprises loading the file data into a local cache.

17. The machine readable storage medium of claim 15 wherein the instructions are further operable to switch the peripheral device from a first mode into a second mode in response to the established connection, wherein the first mode is associated with playback of multimedia files selected from a group consisting of a music file, a video file, a picture file, and a document file on the peripheral device, and the second mode is associated with file transfer access between the peripheral device and the host device.

18. The machine readable storage medium of claim 17 wherein the file system data comprises data for enabling access to files stored on the one or more storage media.

19. The machine readable storage medium of claim 17 wherein the instructions are further operable to concurrently pre-fetch the file system data from the one or more storage media and switch the peripheral device from the first mode into the second mode.

20. The machine readable storage medium of claim 15 wherein the peripheral device is selected from a group consisting of a peripheral disk drive device, a logical disk drive, a removable storage device, a portable device that includes a storage media, and a mass storage device.

29. The machine readable storage medium of claim 15, wherein the file system data comprises at least one of hierarchical file system (HFS) data, new technology file system (NTFS) data, second extended file system (ext2) data or universal disk format (UDF).

21. A machine readable storage medium storing instructions operable to cause data processing apparatus to:

establish a connection between a peripheral device and a host device;

receive a data access message from a host device in response to establishing a connection between a peripheral device and a host device;

switch the peripheral device from a first mode into a second mode in response to the established connection; and

delay sending, from the peripheral device, a response to the data access message until the peripheral device completes the switch from a first mode into a second mode.

22. The machine readable storage medium of claim 21 wherein the instructions are further operable to cause data processing apparatus to delay sending the response to the data access command until buffers are cleared in the peripheral device.

23. The machine readable storage medium of claim 21 wherein the first mode enables playback of media files comprising at least one of a music file, a video file, a picture file, or a document file on the peripheral device, and the second mode comprises file transfer access between the peripheral device and the host device.

24. The machine readable storage medium of claim 21 wherein the peripheral device is selected from a group consisting of a peripheral disk drive device, a logical disk drive, a mass storage device, a removable storage device, and a portable device that includes a storage media.

25. The machine readable storage medium of claim 21 wherein the instructions are further operable to cause data processing apparatus to pre-fetch file system data from one or more storage media accessible by the peripheral device into a memory of the peripheral device in response to the established connection, the file system data pre-fetched prior to receiving a request for the file system data from the host device, and switch the peripheral device from the first mode into the second mode in parallel, wherein the file system data is adapted for providing at least one of read or write access to the one or more storage media.

30. The machine readable storage medium of claim 25, wherein the file system data comprises at least one of hierarchical file system (HFS) data, new technology file system (NTFS) data, second extended file system (ext2) data or universal disk format (UDF).

33. The machine readable storage medium of claim 21, wherein the data access message from the host device indicates a request for the host device to have read or write access to data stored by the peripheral device;

and

wherein the peripheral device is not configured to provide the host device with read or write access to the data when operating in the first mode, and wherein the peripheral device is configured to provide the host device with read or write access to the data when operating in the second mode.

26. A system for establishing communications involving a peripheral device, the system comprising:

a establishing means operable to establish a connection between a peripheral device and a host device;

a retrieval means operable to pre-fetch file system data from one or more storage media accessible by the peripheral device into a memory of the peripheral device in response to the established connection, the file system data pre-fetched prior to receiving a request for the file system data from the host device, wherein the file system data is adapted for providing at least one of read or write access to the one or more storage media;

a receiving means operable to receive a data access command from a host device in response to establishing a connection between a peripheral device and a host device;

a switching means operable to switch the peripheral device from a first mode into a second mode in response to the established connection; and

a delay means operable to delay sending, from the peripheral device, a response to the data access command until the peripheral device completes the switch from a first mode into a second mode.

31. The system of claim 26, wherein the file system data comprises at least one of hierarchical file system (HFS) data, new technology file system (NTFS) data, second extended file system (ext2) data or universal disk format (UDF).

34. The system of claim 26, wherein the data access message from the host device indicates a request for the host device to have read or write access to data stored by the peripheral device;

and

wherein the peripheral device is not configured to provide the host device with read or write access to the data when operating in the first mode, and wherein the peripheral device is configured to provide the host device with read or write access to the data when operating in the second mode.