Information recording medium and region management method thereof

• US 20060195672A1
• Filed: 02/19/2004
• Published: 08/31/2006
• Est. Priority Date: 02/20/2003
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Inoue, Shinji, Maeda, Takuji
• Granted Patent: US 7,653,796 B2
• Time in Patent Office: Days
• US Class Current: 711/170
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/0674 Disk device
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

A region management method for an information recording medium capable of maintaining data interchangeability among devices and preventing malfunction when one information recording medium shared among devices different in type or number of file systems that can be interpreted by devices is provided. A recording region of the information recording medium is divided into a plurality of regions, and region information such as position and size of each region is held in the information recording medium. Different file systems are constructed in individual data recording regions. In response to a command from an information processing apparatus, accessible regions by the information processing apparatus are changed over by, for example, referring to validity flag information that indicates a presently valid region.

Claims

1. A region management method of an information recording medium, the information recording medium having a data recording region for storing data, the data stored in the recording medium being managed as a file by a file system, the region management method comprising:

dividing the data recording region into a plurality of recording regions each managed by different file systems individually;

receiving a command from outside of the information recording medium; and

selecting one of the divided recording regions according to the received command, as a region accessible from outside of the information recording medium.

2. The region management method according to claim 1, further comprising:

setting a validity flag indicating a region which is valid presently among the plurality of divided recording regions, in the information recording medium; and

referring to the validity flag, prior to access to the data recording region in the information recording medium, to select the one of the divided recording regions to be accessible.

3. The region management method according to claim 2, further comprising setting the validity flag to a specified value when initializing the information recording medium, and afterward setting the validity flag again according to a command received from outside of the information recording medium.

4. The region management method according to claim 1, further comprising storing size of each divided recording region in the information recording medium, and changing the size of each divided recording region according to a command received from outside of the information recording medium.

5. The region management method according to claim 1, wherein the information recording medium is managed by file systems each constructed in each divided recording region and includes a protect region and a user data region, the protect region being accessible by a device connected to the information recording medium only when the device is authorized, the user data region being accessible from the device independently of authorization.

6. A region management method of an information recording medium, the information recording medium having a data recording region for storing data, the data stored in the recording medium being managed as a file by a file system, the region management method comprising:

dividing the data recording region into a plurality of recording regions each managed by different file systems individually;

storing a plurality of storage blocks in a consecutive recording region in the information recording medium, the storage block having constant data size, each storage block storing a partition table which is provided to each divided recording region and is information about a region management which is used by each file system of each divided region;

storing a valid block number indicating a storage block which includes the partition table for a region in the divided recording regions that is accessible from outside of the recording medium;

receiving a command from outside of the information recording medium;

according to the received command, referring to the validity block number, selecting one storage block from the plurality of storage blocks, and determining a partition table to be accessible from outside of the information recording medium.

7. The region management method according to claim 6, further comprising disposing the partition table included in the selected storage block at the beginning of logic address space of the information recording medium.

8. The region management method according to claim 6, wherein the partition table includes start address of the region managed by the file system and size of the region, and regions specified by the partition tables do not overlap each other.

9. The region management method according to claim 6, wherein

the data recording region is managed by file systems each constructed in each divided recording region, and includes a protect region and a user data region, the protect region being accessible by a device connected to the information recording medium only when the device is authorized, the user data region being accessible from the device independently of authorization, and the information about a region management is provided to the user data region and the protect region, and regarding the same divided recording region, a partition table for the user data region and a partition table for the protect region are managed in pairs.

10. An information recording medium having a data recording region for storing data, wherein

a) the data recording region is divided into a plurality of regions, a different file system for managing data stored in each region is constructed in each divided region, and

b) the information recording medium comprises a region information storage section that stores a validity flag showing a region in the divided regions that is accessible from an external device, and an access region judging section that selects one valid region by referring to the validity flag and allows access to the selected region by the external device.

11. An information recording medium having a data recording region for recording data, wherein

a) the data recording region is divided into a plurality of recording regions each managed by different file system, and

b) the information recording medium includes:

a partition table storage section that stores a plurality of storage blocks for storing a partition table which is information about region management used by the file system in each divided region,

a command receiving section that receives a command from outside of the information recording medium,

a region information storage section that stores valid block number indicating a storage block of the plurality of storage blocks in the partition table storage section, the storage block including the partition table which is accessible from an external device, and

an access region judging section that selects one storage block from the partition table storage section with reference to the valid block number, and determines the partition table which is accessible from the external device, on the basis of a command received from outside of the information recording medium.

12. A region management method of an information recording medium having a data recording region for storing data, the data stored in the recording medium being managed as a file by a file system, the third region management method comprising:

storing a plurality of types of sizes of the data recording region accessible from outside of the information recording medium; and

changing over the size of accessible region according to a command receiving from outside of the information recording medium.

13. The region management method according to claim 12, further comprising

storing valid region information which is information indicating the size which is presently valid in a plurality of types of sizes of data recording regions accessible from outside of the information recording medium,

prior to access to the data recording region in the information recording medium, recognizing the size of accessible region by referring to the valid region information, and judging possibility of access.

14. The region management method according to claim 13, further comprising

setting the valid region information to one of the plurality of sizes stored, simultaneously with initialization of the information recording medium, and

setting again the valid region information according to a command received from outside of the information recording medium.

15. The region management method according to claim 12, wherein the stored size of each region can be changed by a command received from outside of the information recording medium.

16. The region management method according to claim 12, wherein the information recording medium includes a protect region and a user data region, the protect region is accessible by a device connected to the information recording medium only when the device is authorized, and the user data region is accessible from the device independently of authorization.

17. An information recording medium having a data recording region for recording data, comprising:

a region information storage section that stores a plurality of types of sizes of the data recording region accessible from outside of the information recording medium, and valid region information which is information indicating the size which is presently valid in a plurality of types of sizes of data recording regions accessible from outside of the information recording medium; and

an access judging section that, prior to access to the data recording region in the information recording medium, recognizes the size of accessible region by referring to the valid region information, and judges possibility of access.

18. The information recording medium according to claim 17, wherein the stored size of each region can be changed by a command received from outside of the information recording medium.

19. A region management method of an information recording medium having an data recording region for storing data, the data stored in the recording medium being managed as a file by a file system, the region management method comprising:

storing information providing size of data recording region to a specific register;

setting the information providing size of data recording region in the register simultaneously with initialization of the information recording medium to a specific value smaller than the actual size of the data recording region; and

setting again, according to a command received from outside of the information recording medium, the information providing size of data recording region in the register to an actual size of the information recording medium.

20. The region management method according to claim 19 further comprising, when setting the size of the data recording region in the register at 0 kB, preventing the information recording medium from receiving a data read command or data write command from outside of the information recording medium.

21. The region management method according to claim 19 wherein, the information recording medium includes a protect region and a user data region, the protect region is accessible by a device connected to the information recording medium only when the device is authorized, the user data region is accessible from the device independently of authorization, at this time, the information providing size of data recording region in the register is set to provide the size of the user data region.

22. An information recording medium having a data recording region for recording data, comprising:

a register that stores information providing size of data recording region to a specific register;

a command receiver that receives a command from outside of the information recording medium; and

an access region judging section that sets the information providing size of data recording region in the register simultaneously with initialization of the information recording medium to a specific value smaller than the actual size of the data recording region, and sets again, according to a command received from outside of the information recording medium, the information providing size of data recording region in the register to an actual size of the information recording medium.