Method of operating a data processing system

• US 5,086,502 A
• Filed: 11/13/1989
• Issued: 02/04/1992
• Est. Priority Date: 07/11/1989
• Status: Expired due to Term

• Current Assignee: Computer Associates Think Inc. (Broadcom, Inc.)
• Original Assignee: Intelligence Quotient International Ltd (Broadcom, Inc.)
• Inventors: Malcolm, Peter B.
• Primary Examiner(s): BEAUSOLIEL JR, ROBERT W
• Application Number:
  US07/435,138
• Time in Patent Office: 813 Days
• Field of Search: 364/200, 364/900, 371/12, 371/13, 371/10.1
• US Class Current: 714/6.13
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 11/1469 Backup restoration techniques

Abstract

A method of operating a data processing system, in particular a micro-computer, comprises a backup process in which a copy of every change made to a storage medium is recorded as the change occurs. Write operations for writing data to the storage medium are each preceded by a backup write operation to backup storage means, successive backup write operations being controlled so as to be stored as a sequential list in the backup storage means in the form of location blocks and data blocks to avoid the overwriting occurring in the storage medium. These backup write operations are executed at the level of the basic input/output system (BIOS) of the microcomputer in such a manner that normal use of the computer is unaffected. The method also includes a restore process in which bad sectors of a destination storage device are avoided by translating the file allocation table (FAT) and directories of the original data.

Claims

1. A method of operating a microprocessor-based data processing system including a random access memory, a central processing unit and a non-volatile storage device, the method comprising the steps of:

providing first instructions sorted in the memory to the central processing unit to cause the central processing unit to write data periodically to basic storage means forming at least part of the storage device, and

for a plurality of such first write operations, instructing the central processing unit to execute a plurality of corresponding backup write operations to write the same data to backup storage means, each said backup write operation being performed by a second sequence of instructions stored in said memory, and said second sequence of instructions being associated with said first write operations for writing data to the basic storage means.

2. A method according to claim 1, wherein the backup write operations comprise writing the same said data to another non-volatile storage device.

3. A method according to claim 1, wherein the said backup write operations are controlled such that the data for successive backup write operations are stored at different locations in the backup storage means whereby data which is overwritten in the said basic storage means is retained in the backup storage means.

4. A method according to claim 1, wherein said instructions for causing the backup write operations are stored and are executed at a basic input/output level of the data processing system.

5. A method according to claim 1, wherein information copied to the backup storage means is stored as a sequential list of write operations.

6. A method according to claim 1, wherein each write operation is stored in the backup storage means as a location element and a data element, the location element containing information relating to the location of the data when stored in the basic storage means.

7. A method according to claim 6, wherein each location element has associated with it information relating to the date and time of the corresponding write operation.

8. A method according to claim 6, including a restoring of data from the backup storage means to destination storage means, wherein the restoring step comprises determining the location of faulty parts of the destination storage means and establishing a translation table for substituting new location elements in place of the stored location elements so that data can be restored to correctly functioning parts of the destination storage means.

9. A method according to claim 8, further including alteration of a file allocation table and directories associated with the original data.

10. A method of operating a data processing device comprising the steps of:

providing backup storage means for storing as a sequential list write operations written to basic storage means, each write operation being stored in the backup storage means as a location element and a data element with the location element containing information relating to the location of the data element when stored in the basic storage means,

determining the location of faulty parts of a destination storage means, and

establishing a translation table for allocating to the data element new location elements in place of the stored location elements for restoring the data elements to correctly functioning parts of the destination storage means.

11. A method according to claim 10, including alteration of a file allocation table and directories in an original data.

12. A method according to claim 10, wherein the instructions of controlling the restoring of data are stored and executed at a basic input/output level of the data processing system.

13. A method according to claim 10, wherein the translation table is established at a basic input/output level of the data processing system.

14. In a microprocessor-based data processing system comprising a random access memory, a central processing unit, and a non-volatile storage device, a method of providing a backup for data written to the non-volatile storage device, wherein the method includes the steps of:

performing, for each write operation in which data is written to basic storage means forming at least part of said storage device, a backup write operation in which said data is also written as a data block to backup storage means together with a location block containing information relating to the location of said data when stored in the basic storage means, and

storing the backup write operations for successive write operations to said basic storage means in the backup storage means as a sequential list of location and data block pairs stored in different respective locations of the backup storage means, each said backup write operation being performed by a first sequence of instructions which are stored in said random access memory and are associated with a second sequence of instructions for executing said write operations for writing data to the basic storage means.

15. A method according to claim 14, wherein the write operations to the basic storage means and the backup storage means are performed at the level of a basic input/output system (BIOS).

16. A method according to claim 14, further including a method for restoring data from the backup storage means to destination storage means, wherein the restoring method includes establishing a translation table in said memory, reading a said location block from the backup storage means, assigning a new location if the location in the destination storage means represented by said location block is faulty and registering the new location in the translation table in association with the former location, reading said data block associated with said location block from the backup storage means and writing it to said destination storage means, repeating said reading, assigning, reading and writing steps until all a data required to be restored has been restored to the destination storage means.

17. A method according to claim 16, wherein the restoring method further includes the steps of scanning a file allocation table and directory and altering address references therein of locations which are indicated by the translation table as having been changed.

18. An improved microprocessor-based data processing system comprising a random access memory, a central processing unit, a non-volatile basic storage means, and non-volatile backup storage means, wherein the improvement comprises:

means for performing a backup write step corresponding to each write operation in which data is written to said basic storage means, said backup write steps comprising the writing of said write operation to the backup storage means as a location block and a data block, the location block containing information relating to the location of the data block in said basic storage means, and

means for writing successive said write operations to said backup storage means as a sequential list, each location and data block pair being stored in a different respective location in the backup storage means, the backup write step being performed by a first sequence of instructions stored in said memory and associated with a second sequence of instructions for executing said write operation in which data is written to said basic storage means.

19. A system according to claim 18, wherein the memory has stored therein instructions for performing the backup write step, said instructions being stored at the level of a basic input/output system (BIOS).

20. A system according to claim 18, further including:

destination storage means for storing data stored in said backup means, and

means for establishing a translation table in said memory,

means for reading a said location block from the backup storage means,

means for assigning a new location if the location in the destination storage means represented by said location block is faulty,

means for registering the new location in the translation table in association with the former location,

means for reading said data block associated with said location block from the backup storage means and writing it to said destination storage means, and

means for repeating said reading, assigning, reading and writing until all the data required to be restored has been restored to the destination storage means.

21. A system according to claim 20, arranged to store a file allocation table and a directory, wherein the system is further programmed to scan said file allocation table and directory, and to alter address references therein of locations which are indicated by the translation table as having been changed.