JPH11194938A - Memory managing method for computer having hard disk drive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a hard disk against a computer virus by updating a read/ write table by a computer for the storage of the address of a modified part of a system buffer space and the address of the part of a system file(SF) of a system disk drive(SDD) corresponding to it. SOLUTION: The hard disk drive 20 is sectioned into the system disk drive(SDD) 21, system buffer space 23, read/write table 24, etc. Then the modified part of the system file (SF) of the SDD 21 is stored in the system buffer space 23 by a CPU 11 instead of the SDD 21 so as to maintain the SF in its initial form. At this time, the read/write table 24 is updated by the CPU 11 so as to store the address of the modified part of the system buffer space and the address of the part of the SF of the SDD 21 corresponding to the updated part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a memory management method for a computer having a hard disk drive, and more particularly, to providing appropriate protection of the hard disk drive against computer viruses, and for saving system files in the hard disk drive to its initial form. The present invention relates to a memory management method for a personal computer having a hard disk drive that allows restoration to a personal computer.

[0002]

2. Description of the Related Art At present, a partitioning scheme is used to divide a hard disk drive of a personal computer exclusively into several system disk drives for storing system files and a system disk drive.
e) Data disk drive to be divided (part)
It is technically available to make it possible to use the memory space efficiently. Furthermore, a backup scheme is technically used in which the initial version of the system file is stored as a backup file when the system file is changed, while the changed version of the system file is stored as a new system file. It is possible. In this way, portions of the new system file may still be recovered by the presence of the backup file when the new system file does not work well due to things like computer viruses.

[0003] A major disadvantage of known backup schemes is that once the system files are exposed to numerical changes, the system files are not restored to their initially installed form. Mirror schemes are also technically available, in which the contents of the primary hard disk drive are copied to the backup hard disk drive, so that when the primary hard disk drive is damaged, the contents of the primary hard disk drive are still present due to the presence of the backup hard disk drive Available.
However, known mirror schemes cannot provide protection against computer viruses because computer viruses written to the primary hard disk drive are also copied to the backup hard disk drive.

[0004]

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a memory for a personal computer having a hard disk drive capable of properly protecting the hard disk drive against computer viruses and restoring files in the hard disk drive to an initial form. To provide a management method.

[0005]

SUMMARY OF THE INVENTION The object is to divide a hard disk drive into at least one system disk drive for storing system files, a data disk drive, a system buffer space, and a read / write table. And selectively operating the computer in one of the unrestricted mode and the restricted mode. In the unrestricted mode, the storage of the system file by the computer and the modification of the system file of the system disk drive are allowed. The modified portion of the system file on the system disk drive is stored and read by the computer in the system buffer space instead of the system disk drive to maintain the system file on the system disk drive in its initial form. Computer having a hard disk drive in which the read / write table is updated by the computer to store the address of the changed portion of the system buffer space and the address of the portion of the system file on the system disk drive corresponding to the changed portion. Is achieved by the memory management method.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of the invention will become apparent from the following detailed description of a preferred embodiment, taken in conjunction with the drawings, in which: FIG. Referring to FIG. 1, a preferred embodiment of the memory management method according to the present invention is performed by a standard personal computer, which comprises a central processing unit (CPU).
11, the basic input / output system (B
IOS) memory 12, hard disk drive 20 to C
A hard disk interface 13 interconnecting the PU 11 and an interface bus such as an ISA bus 14 are included. In the preferred embodiment, a standard computer 10
Is a plug-in type read-only memory (ROM) card 30 for enabling the memory management method of the present invention to be executed.
And a programmable logic array (PAL) decoder 3
1 and a pre-programmed memory 32 such as an electrically programmable read only memory (EPROM) or a flash memory are provided on the ISA bus 14.

Once the ROM card 30 is installed on the ISA bus 14, when the power to the computer 10 is turned on, the CPU 11 operates as described in the prior art with the hardware configuration operation connected to the BIOS memory 12. Make In the prior art, control of the computer 10 is taken over by the disk operating system after the hardware configuration operation is completed. However, in the memory management method according to this embodiment, the presence of the ROM card 30 on the ISA bus 14 causes the computer 10 to give its user the choice of partitioning the hard disk drive 20 before control of the computer 10 is taken over by the disk control system. Controlled.

In the embodiment shown in FIG.
0 is at least one system disk drive 21,
Data disk drive 22, system buffer space 2
3, read / write table 24, ROM card reservation (reserve) space 25. In this example, DO
S5.00, DOS 6.22, WIN 3.11, WIN
There are three system disk drives 21 with different memory sizes for storing different system files such as 95. The data disk drive 22 is a system disk drive 21 as is known in the art.
Is divided exclusively by The system buffer space 23 is selected to be the same size as the largest of the system disk drives 21. In this example, the sizes of the three system disk drives 21 are 700 MB and 30 MB, respectively.
0 MB. 100 MB, so the size of the system buffer space 23 is selected to be 700 MB. The ROM card reservation space 25 allocates a space necessary for running a computer program in the memory 32 of the ROM card 30.

After the hard disk drive is partitioned, the computer program of the ROM card 30 is executed by the computer 10 in a non-restricted mode by the user.
0 can be activated, where the system files can be stored on the system disk drive 21 and the system files in the system disk drive 21 can be changed. Thereafter, the computer program in the ROM card 30 allows the computer 10 to allow the user to operate the computer 10 in the restricted mode, wherein the modified portion of the system files on the system disk drive 21 The system files are stored by the CPU 11 in the system buffer space 23 instead of the system disk drive 21 to maintain the system files in their initial form. At this time, the read / write table 24 is updated by the CPU 11 to store the address of the changed part of the system buffer space 34 and the address of the part of the system file of the system disk drive 21 corresponding to the updated part. .

Referring to FIGS. 1 and 2, there is shown a flowchart of the general operation of the computer 10 coupled to the hard disk drive 20. Upon detecting that the hard disk drive 20 is used, the CPU 11 performs a read operation, a write operation and a write operation. Detects whether a command to be performed to determine whether a write operation or a format emulation operation is performed is a read command, a write command, or a format command.

Referring to FIGS. 1 and 3, this illustrates a hard disk write operation of computer 10 according to a preferred embodiment, which detects a write command for writing to hard disk drive 20 and causes ROM card 30 to store data. The computer program detects whether the write address is on system disk drive 21, data disk drive 22, or the other, and whether computer 10 is operating in a restricted or unrestricted mode. CPU
11 is enabled to write to the appropriate system disk drive 21 when the write address is in the latter while the computer 10 is operated in the unrestricted mode.
CPU 11 is enabled to write to system buffer space 23 when the write address is in one of system disk drives 21 while computer 10 is operating in the restricted mode. At the same time, CPU 10 is enabled to update read / write table 24 to store the write address and the address in system buffer space 23 corresponding to the write address therein. CP
U11 is enabled to further write to data disk drive 22 when the write address is in the latter, regardless of whether computer 10 is operating in a restricted or unrestricted mode.

In this embodiment, if the write address is not in one of the system disk drive 21 and the data disk drive 22, the CPU 11 is enabled to perform a write emulation operation, where the write completion signal is Generated thereby without actually performing a write operation. This provides a safeguard against the malfunction of different software applications due to computer viruses.

Referring to FIGS. 1 and 4, this illustrates a hard disk read operation of the computer 10 according to the preferred embodiment. Upon detection of a read command to read the hard disk drive 20, the computer program of the ROM card 30 is read by the system disk drive 21. , The data disk drive 22 or the other, and whether the computer 10 is in the restricted or unrestricted mode, and controls the CPU 11. The CPU 11 is enabled to read the appropriate system disk drive 21 when the read address is in the latter while the computer 10 is operated in the non-restricted mode. The CPU 11 is enabled to read the system disk drive 21 when the read address is in the latter while the computer 10 is operated in the restricted mode and is not recorded in the read / write table 24. While the computer 10 is operating in the restricted mode, the read address is in one of the system disk drives 21, and when recorded in the read / write table 24, the address of the system buffer space 23 corresponding to the read address is read. To be read. CPU 11 is enabled to further read data disk drive 22 when the read address is in the latter, regardless of whether computer 10 is operating in a restricted or unrestricted mode.

In the preferred embodiment, if the read address is not in either system disk drive 21 or data disk drive 22, CPU 11 is enabled to perform a read emulation operation, where the read completion signal is actually Generated thereby without performing a read operation. This prevents damage to different software applications by computer viruses.

Referring again to FIGS. 1 and 2, upon detecting a format command, the computer program in ROM card 30 enables CPU 11 to perform a format emulation operation, where a format complete signal prevents unwanted erasure of system files. This occurs without actually formatting any of the system disk drives 21 for formatting.

If the data in the system buffer space 23 does not operate properly (corrupted), the ROM card 3
0, the computer program in the memory 32 allows selective operation of the computer 10 in the system recovery mode;
Here, the CPU 11 clears the read / write table 24 so that the CPU 11 enables the system disk drive 21 regardless of whether the computer 10 is operated in the restricted or unrestricted mode when the read address is in the latter. Thus, the hard disk drive 20 is properly protected against computer viruses, and the system files in the hard disk are restored to their initial form.

Preferably, the computer program on the ROM card 30 allows the user of the computer 20 to select the latter operation of the update mode, wherein the system files on the system disk drive 21 are used to keep the modified system files from being damaged by computer viruses. It is updated with the changed part of the system buffer space 23 for protection.

Although the present invention has been described in terms of the most practical and preferred examples, the present invention is not limited to the disclosed embodiments, but is intended to cover all such modifications and equivalent combinations. It is intended to cover a variety of variations that fall within the spirit and scope of the broad interpretation.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of a circuit showing a computer having a hard disk drive partitioned by a partitioning scheme used in a preferred embodiment of the memory management method of the present invention.

FIG. 2 is a flowchart illustrating the general operation of a computer coupled to a hard disk drive according to a preferred embodiment;

FIG. 3 is a flowchart illustrating a write operation of a hard disk of a computer according to a preferred embodiment;

FIG. 4 is a flowchart illustrating a read operation of a hard disk of a computer according to a preferred embodiment;

[Explanation of symbols]

 Reference Signs List 10 computer 11 CPU 12 BIOS memory 13 hard disk interface 14 ISA bus 20 hard disk drive 21 system disk drive 22 data disk drive 23 system buffer space 24 read / write table 25 ROM card reserved space 30 ROM card 31 PAL decoder 32 EPROM memory

Claims (11)

[Claims] 1. partitioning a hard disk drive into at least one system disk drive for storing system files, a data disk drive, a system buffer space, and a read / write table; Selectively operating in one of the restricted modes. In the non-restricted mode, the storage of system files by the computer and the modification of the system files on the system disk drive are allowed. In the restricted mode, the modification of the system files on the system disk drive is permitted. The read portion is stored by the computer in the system buffer space instead of the system disk drive to maintain the system files of the system disk drive in its initial form, and the read / write table is stored in the system. A memory management method for a computer having a hard disk drive that is updated by a computer to store an address of a changed portion of the system buffer space and an address of a portion of a system file of a system disk drive corresponding to the changed portion. 2. When the computer is operated to perform a read operation of the hard disk drive, the computer is enabled to read the system disk drive when the read address is on the system disk drive while the computer is operating in the unrestricted mode. If the read address is on the system disk drive while the computer is operating in restricted mode,
Enable the computer to read the system disk drive when not recorded in the write table, and if the read address is on the system disk drive while the computer is operating in restricted mode,
The method of claim 1, further comprising the steps of: enabling the computer to read an address in the system buffer space corresponding to the read address when recorded in the write table. 3. The method of claim 2, further comprising the step of enabling the computer to read the data disk drive when the read address is on the data disk drive, whether the computer is operated in the restricted or unrestricted mode. Memory management method. 4. The method of claim 1, further comprising the step of enabling the computer to perform a read emulation operation in which a read completion signal is generated without actually performing the read operation when the read address is not present in the system disk drive and the data disk drive. Item 3. The memory management method according to Item 2. 5. A read / write table for enabling a computer to read a system disk drive when a read address is on the system disk drive, whether the computer is operated in a restricted or unrestricted mode. 3. The memory management method according to claim 2, further comprising the step of selectively operating a computer that clears the system in a system recovery mode. 6. A computer that writes to a system disk drive when a write address is on the system disk drive while the computer is operated in an unrestricted mode when the computer is operated to perform a write operation of the hard disk drive. And write to the system buffer space when the write address is in the system disk drive while the computer is operated in the restricted mode, and the system buffer corresponding to the write address and the write address in the read / write table. The method of claim 5, further comprising enabling the computer to record addresses of the space. 7. The method of claim 6, further comprising the step of enabling the computer to write to the data disk drive when the write address is on the data disk drive, whether the computer is operated in the restricted or unrestricted mode. Memory management method. 8. Enabling the computer to perform a write emulation operation in which a write completion signal is generated without actually performing the write operation when the write address is not present in the system disk drive and the data disk drive. The memory management method according to claim 7, further comprising: 9. The memory management method according to claim 1, wherein the hard disk drive is divided before the control of the computer is taken over by the disk operating system. 10. The method of claim 1, wherein detecting the format command further comprises enabling the computer to perform a format emulation operation in which a format complete signal is generated without actually formatting the system disk drive. . 11. The method of claim 1, further comprising the step of selectively operating the computer in an update mode in which system files on the system disk drive are updated with changed portions of the system buffer space.