CN113010107B

CN113010107B - Data storage management method, device, computer equipment and storage medium

Info

Publication number: CN113010107B
Application number: CN202110219880.1A
Authority: CN
Inventors: 肖蔓君; 甘金涛; 徐超; 李小凤
Original assignee: Shenzhen Union Memory Information System Co Ltd
Current assignee: Shenzhen Union Memory Information System Co Ltd
Priority date: 2021-02-26
Filing date: 2021-02-26
Publication date: 2023-08-29
Anticipated expiration: 2041-02-26
Also published as: CN113010107A

Abstract

The application discloses a data storage management method, a device, computer equipment and a storage medium, wherein the method comprises the following steps: analyzing key data of an operating system to obtain key data characteristics; acquiring write data issued by a host; judging whether the write data has key data characteristics or not; if the write data has the key data characteristics, judging the write data as the key data, improving the protection level of the write data and writing the data. According to the scheme, when the host computer issues the written data, whether the written data is the key data is determined according to the key data characteristics by analyzing the key data characteristics of the key data of the operating system, if the written data is the key data, a protection strategy with higher level is adopted for storage management, so that data damage caused by physical risk of NANDflash is avoided, and data security is improved.

Description

Data storage management method, device, computer equipment and storage medium

Technical Field

The present application relates to the field of data management, and more particularly, to a data storage management method, apparatus, computer device, and storage medium.

Background

SSD, english is also known as Solid State Drive, and is also known as solid state disk, has been widely used in various situations, and has gradually replaced traditional HDD in PC market at present, providing better experience for users in terms of reliability and performance.

In the existing storage management scheme, the SSD, as a receiving end, acquires commands formulated by various protocols issued from the host, and completes communication interaction with the host, data transmission, and the like. Since the SSD is not concerned with the content of data, the processing of data from the host is generally performed with various considerations of NAND flash writing according to parallel performance requirements, data security, etc., but these considerations are irrelevant to the content.

In use, common SSD abnormal manifestations, such as hard disk failure to identify, system start failure, system blue screen, etc., are mostly directly related to key data damage or loss of the operating system. Because of the guiding loss of the key data, the operating system cannot work normally, and although the user data is safe in the hard disk, the user data cannot be accessed, so that the normal use of the user is affected.

The information disclosed in this background section is only for enhancement of understanding of the general background of the application and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

In order to solve the above-mentioned drawbacks of the prior art, an object of the present application is to provide a data storage management method, apparatus, computer device and storage medium.

In order to achieve the above purpose, the technical scheme of the application is as follows:

in a first aspect, the present application provides a data storage management method, including the following steps:

analyzing key data of an operating system to obtain key data characteristics;

acquiring write data issued by a host;

judging whether the write data has the key data characteristics or not;

if the write data has the key data characteristics, judging the write data as the key data, improving the protection level of the write data and writing the data.

In a second aspect, the present application provides a data storage management apparatus, including:

the feature analysis unit is used for analyzing key data of the operating system to obtain key data features;

the data acquisition unit is used for acquiring write data issued by the host;

the data judging unit is used for analyzing whether the write data has the key data characteristics;

and the data writing unit is used for judging the write data as the key data when the write data has the key data characteristics, improving the protection level of the write data and writing the data.

In a third aspect, the present application proposes a computer device comprising a memory and a processor, the memory having stored thereon a computer program, the processor implementing a data storage management method as described above when executing the computer program.

In a fourth aspect, the present application proposes a storage medium storing a computer program which, when executed by a processor, implements a data storage management method as described above.

Compared with the prior art, the application has the beneficial effects that: the application provides a data storage management method, a data storage management device, computer equipment and a storage medium. Specifically, when a host computer issues write-in data, the data storage management method analyzes the characteristics of key data of an operating system, further determines whether the write-in data is the key data according to the key data characteristics, and if the write-in data is the key data, adopts a protection strategy with higher level to carry out storage management, avoids data damage caused by physical risk of NAND flash, and improves data security.

The application is further described below with reference to the drawings and specific embodiments.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic flow chart of a data storage management method according to an embodiment of the present application;

FIG. 2 is a schematic sub-flowchart of a data storage management method according to an embodiment of the present application;

FIG. 3 is a schematic sub-flowchart of a data storage management method according to an embodiment of the present application;

FIG. 4 is a schematic sub-flowchart of a data storage management method according to an embodiment of the present application;

FIG. 5 is a schematic block diagram of a data storage management device according to an embodiment of the present application;

FIG. 6 is a schematic block diagram of a feature analysis unit of a data storage management device according to an embodiment of the present application;

FIG. 7 is a schematic block diagram of a data judging unit of a data storage management device according to an embodiment of the present application;

FIG. 8 is a schematic block diagram of a data writing unit of a data storage management device according to an embodiment of the present application;

fig. 9 is a schematic block diagram of a computer device according to an embodiment of the present application.

Detailed Description

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

It should be understood that the terms "comprises" and "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be further understood that the term "and/or" as used in the present specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes such combinations.

Fig. 1 is a flow chart of a data storage management method according to an embodiment of the present application. As shown in fig. 2, the method includes the following steps S110 to S150.

S10, analyzing key data of the operating system to obtain key data characteristics.

In this embodiment, the data management manners of different operating systems are different, but all the operating systems store system management data (such as a driver, a registry, etc., but not user data, and guarantee privacy security of the user data) in corresponding data sectors, so it can be further determined whether the write data issued by the host is critical data by determining whether the LBA (Logical Block Address ) of the write data is in the data sector for storing the critical data.

In this scheme, the key data of the operating system is analyzed to obtain the key data feature, where the key data feature is the sector position or range for storing the key data, and whether the write data is to be written into the corresponding sector position can be determined by analyzing the LBA of the write data, so that whether the write data is the key data can be determined.

Referring to FIG. 2, in the present embodiment, step S10 includes steps S11-S1

S11, acquiring a data sector managed by an operating system.

S12, identifying the position of the key sector where the key data in the data sector are located.

S13, analyzing the key sector to obtain the position of the key guide sector.

S14, taking the key sector position and the key guide sector position as key data characteristics.

In this embodiment, the method analyzes and marks the key LBA of the system boot data by acquiring the data sector managed by the operating system, that is, analyzing the data sector storing the system boot data (key data), and determines the key sector containing the key data by analyzing the starting process of the operating system, and further analyzes the key sector in a targeted manner, thereby obtaining the key boot sector position stored in the key sector, and taking the key sector position and the key boot sector position as key data features for evaluating the write data.

The above-mentioned critical boot sector location is a data sector located in another partition and used for storing system data, and the critical boot sector location information is recorded in a critical sector, for example, in a Windows system, LBA 0 of a general main partition is a critical sector, and a critical data sector of another active partition of the hard disk is also recorded in LBA 0, that is, the above-mentioned critical boot sector.

Taking the WIN10 operating system boot process as an example, the Windows boot process typically includes the following four phases:

1) Preboot: the Preboot is POST (Power On Self Test) to load a firmware configuration, where for a hard disk such as an SSD, it is detected whether a valid system is involved.

2) Windows Boot manager confirm whether multiple operating systems are installed, if so, provide a selection menu for selection;

3) Windows OS loader, loading an important driver through WinLoad.exe to start the Windows kernel, enabling the kernel to communicate with hardware by using the driver, and executing and guiding other necessary operations;

4) Windows NT OS Kernel obtaining registry settings and other drivers, etc. once read successfully, the system manager process will obtain control, load user interface, rest of software and hardware, etc.

The files and paths loaded by the startup procedure of step 3 are different according to the difference of BIOS or UEFI, but all are carried out according to specific rules on LBAs. Taking the legacy MBR (Master Boot Record) loading process as an example, after the computer is started, firstly, the computer accesses LBA 0 of the hard disk, and in the MBR 512B, relevant information of the hard disk and size and position information of each partition of the hard disk are recorded.

The bootable "active partition" is then found from the partition table, and the first logical sector data from the main partition (active partition) is loaded into memory, the LBA sector being called a volume boot record (Volume Boot Record, VBR, also called partition boot record, partition Boot Record, PBR). The PBR identifies the program location for booting the operating system, and then the control passes to the operating system in the main partition, which manages the hard disk with the information in the main partition.

The specific process comprises the following steps: the PBR searches for a Boot loader (Boot manager) of the bootable operating system under the root directory of the main partition, the computer loads the Boot loader, the Boot loader searches for the Boot configuration data in the main partition, and after the selection of the corresponding operating system is completed, the Boot loader is handed to an operating system initialization program, and the kernel, hardware, services, desktops and the like of the operating system are continuously loaded to complete the starting of the whole operating system.

As is clear from the above process, the starting process of the operating system is strictly managed according to the data boot logic in the LBA, and the starting specific objects of different operating systems are different, but the basic process is the same.

Therefore, the data storage management method provided by the scheme analyzes and marks the key LBA of the system boot data by analyzing the data sector stored with the system boot data (key data), determines the default key sector by analyzing the starting process of the operating system, further analyzes the key sector in a targeted manner, further obtains the key boot sector position stored in the key sector, and takes the key sector position and the key boot sector position as key data characteristics for evaluating the write data.

Specifically, after the important key sector positions and the key boot sector positions are collected, a corresponding sector is added with a flag (such as adding a level flag in a mapping table), and in each module managed by the SSD FTL, the level flag carried in the mapping table can play a role in the operation of each module (such as read-write processing, GC, WL and the like), and a higher-level protection strategy can be adopted for storage management.

S20, acquiring write data issued by the host.

In this embodiment, the SSD receives a write command issued by the host and writes corresponding write data to complete data transmission, but in the conventional scheme, the data from the host end is processed in the same kernel, and generally, various considerations of the NAND flash write mode are performed according to the parallel performance requirement, the data security and the like, but these considerations are irrelevant to the content, and cannot better protect the key data.

S30, judging whether the write data has key data characteristics.

In this embodiment, after the key data feature is obtained, the write data issued by the host is analyzed to determine whether the write data has the corresponding key data feature, if so, the write data can be divided into key data for storage, so as to improve the security of the key data and further improve the security of the corresponding operating system; if the key data features are not provided, the key data features are directly stored as common data, and the common data is lost and cannot cause the starting failure of an operating system, so that the normal use of a user is ensured.

Referring to fig. 3, in the present embodiment, step S30 includes steps S31 and S32.

S31, analyzing the write data and obtaining LBAs of the write data.

S32, judging whether LBA of the written data is located in a key sector position or a key guide sector position.

In this embodiment, after receiving the write data, the LBA of the write data is analyzed, and whether the LBA of the write data is located in the critical sector position or the critical boot sector position is determined, and if so, it is represented that the LBA of the write data has the critical data feature and should be stored as the critical data.

And S40, if the write data has the key data characteristics, judging the write data as the key data, improving the protection level of the write data and writing the data.

In this embodiment, after it is determined that the write data has the key data feature, the write data is represented as the key data, and at this time, the scheme adopts a storage policy with a higher protection level to write data, so as to avoid data damage caused by physical risk of NAND flash, and ensure data security and stability of the key data.

Referring to FIG. 4, in one embodiment, step S40 includes steps S41-S43.

S41, feeding back the write data with the key data characteristics to the SSD FTL.

S42, adding management labels to the write data through the SSD FTL to mark the protection level of the write data.

S43, according to the protection level of the write data, adopting a corresponding storage strategy to write the data.

In this embodiment, the SSD FTL (Flash translation layer ) is configured to complete the translation from the logical address of the Host to the physical address of the Flash, and when each data is written into the Flash, the FTL records the mapping relationship from the logical address to the physical address of the write data, so that when the Host wants to read the data, the Host reads the real data according to the mapping. When the write data is judged to be key data, the mechanism is fed back to the FLT, the FTL management can decide the protection level of the write data, the protection level is superior to that of common user data, and a management label is added, and the label is used for identifying the protection level of the write data. The protection levels herein are for critical data, and may be divided into two protection levels, for example, very important and generally important, corresponding to the relative very important priority being higher than the general priority of general user data, the higher the protection level, the more resources are allocated when data is written. In the present embodiment, step S43 includes at least one of steps S43a, S43b, and S43 c.

S43a, writing the write data by adopting a high-level RAID storage strategy.

S43b, simultaneously creating multiple data backups for writing data, and writing.

S43c, dividing independent storage areas for writing write data.

It should be appreciated that the key data storage policies or modes of the present scheme include, but are not limited to, the above three. In practical application, multiple storage strategies can be adopted simultaneously for writing data storage, so that the data security of key data is improved, for example, S43a and S43b are adopted simultaneously for key data storage.

According to the data storage management method, when the host computer issues the write-in data, whether the write-in data is the key data is determined according to the key data characteristics by analyzing the key data characteristics of the key data of the operating system, and if the write-in data is the key data, a protection strategy with higher level is adopted for storage management, so that data damage caused by physical risks of NAND flash is avoided, and data security is improved.

Fig. 5 is a schematic block diagram of a data storage management device according to an embodiment of the present application. As shown in fig. 5, the present application also provides a data storage management device corresponding to the above data storage management method. The data storage management apparatus includes a unit for performing the above-described data storage management method, and the apparatus may be configured in a desktop computer, a tablet computer, a portable computer, or the like. Specifically, referring to fig. 5, the data storage management apparatus includes a feature analysis unit 10, a data acquisition unit 20, a data judgment unit 30, and a data writing unit 40.

The feature analysis unit 10 is configured to analyze key data of the operating system to obtain key data features.

Referring to fig. 6, in the present embodiment, the feature analysis unit 10 includes a sector acquisition module 11, a sector identification module 12, a sector resolution module 13, and a feature acquisition module 14;

the sector acquisition module 11 is configured to acquire a data sector managed by the operating system.

The sector identification module 12 is configured to identify a location of a critical sector in which critical data in the data sector is located.

The sector parsing module 13 is configured to parse the key sector to obtain a key pilot sector position.

The feature acquisition module 14 is configured to take the key sector position and the key pilot sector position as key data features.

The data acquisition unit 20 is configured to acquire write data issued by the host.

The data judging unit 30 is used for analyzing whether the write data has key data characteristics.

Referring to fig. 7, in the present embodiment, the data judging unit 30 includes a data analyzing module 31 and an address judging module 32.

The data analysis module 31 is configured to analyze the write data and obtain an LBA of the write data.

The address determination module 32 is configured to determine whether the LBA of the write data is located in a critical sector location or a critical boot sector location.

And a data writing unit 40 for determining the write data as the key data when the write data has the key data feature, improving the protection level of the write data and writing the data.

Referring to fig. 8, in the present embodiment, the data writing unit 40 includes a data feedback module 41, a data grading module 42, and a data writing module 43.

The data feedback module 41 is configured to feed back write data with key data features to the SSD FTL.

The data classification module 42 is configured to apply a management tag to the write data through the SSD FTL to indicate a protection level of the write data.

The data writing module 43 is configured to write data according to the protection level of the write data by adopting a corresponding storage policy.

In this embodiment, the SSD FTL (Flash translation layer ) is configured to complete the translation from the logical address of the Host to the physical address of the Flash, and when each data is written into the Flash, the FTL records the mapping relationship from the logical address to the physical address of the write data, so that when the Host wants to read the data, the Host reads the real data according to the mapping. When the write data is judged to be key data, the mechanism is fed back to the FLT, the FTL management can decide the protection level of the write data, the protection level is superior to that of common user data, and a management label is added, and the label is used for identifying the protection level of the write data. The protection levels herein are for critical data, and may be divided into two protection levels, for example, very important and generally important, corresponding to the relative very important priority being higher than the general priority of general user data, the higher the protection level, the more resources are allocated when data is written.

The above-described data writing module 43 can perform the key data writing in the following ways.

1) Write data is written using a high level RAID storage policy.

2) Multiple copies of data are created simultaneously for writing data and written.

3) The separate storage areas are divided for writing the write data.

It should be appreciated that the key data storage policies or modes of the present scheme include, but are not limited to, the above three. In practical application, multiple storage strategies can be adopted simultaneously for writing data storage, so that the data security of key data is improved, for example, the 1 st and 2 nd storage strategies are adopted simultaneously for key data storage.

According to the scheme, when the host computer issues the write-in data, the key data characteristics of the key data of the operating system are analyzed, whether the write-in data is the key data is further determined according to the key data characteristics, and if the write-in data is the key data, a protection strategy with higher level is adopted for storage management, so that data damage caused by physical risks of NAND flash is avoided, and data security is improved.

It should be noted that, as those skilled in the art can clearly understand, the specific implementation process of the data storage management device and each unit may refer to the corresponding description in the foregoing method embodiment, and for convenience and brevity of description, the description is omitted herein.

Referring to fig. 9, fig. 9 is a schematic block diagram of a computer device according to an embodiment of the present application. The computer device 500 may be a terminal or a server, where the terminal may be an electronic device with a communication function, such as a smart phone, a tablet computer, a notebook computer, a desktop computer, a personal digital assistant, and a wearable device. The server may be an independent server or a server cluster formed by a plurality of servers.

With reference to FIG. 9, the computer device 500 includes a processor 502, memory, and a network interface 505 connected by a system bus 501, where the memory may include a non-volatile storage medium 503 and an internal memory 504.

The non-volatile storage medium 503 may store an operating system 5031 and a computer program 5032. The computer program 5032 includes program instructions that, when executed, cause the processor 502 to perform a data storage management method.

The processor 502 is used to provide computing and control capabilities to support the operation of the overall computer device 500.

The internal memory 504 provides an environment for the execution of a computer program 5032 in the non-volatile storage medium 503, which computer program 5032, when executed by the processor 502, causes the processor 502 to perform a data storage management method.

The network interface 505 is used for network communication with other devices. It will be appreciated by those skilled in the art that the architecture shown in fig. 9 is merely a block diagram of some of the architecture relevant to the present inventive arrangements and is not limiting of the computer device 500 to which the present inventive arrangements may be implemented, as a particular computer device 500 may include more or fewer components than shown, or may combine some of the components, or have a different arrangement of components.

Wherein the processor 502 is adapted to run a computer program 5032 stored in a memory.

It should be appreciated that in an embodiment of the application, the processor 502 may be a central processing unit (Central Processing Unit, CPU), the processor 502 may also be other general purpose processors, digital signal processors (Digital Signal Processor, DSPs), application specific integrated circuits (Application Specific Integrated Circuit, ASICs), off-the-shelf programmable gate arrays (Field-Programmable Gate Array, FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. Wherein the general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

Those skilled in the art will appreciate that all or part of the flow in a method embodying the above described embodiments may be accomplished by computer programs instructing the relevant hardware. The computer program comprises program instructions, and the computer program can be stored in a storage medium, which is a computer readable storage medium. The program instructions are executed by at least one processor in the computer system to implement the flow steps of the embodiments of the method described above.

Accordingly, the present application also provides a storage medium. The storage medium may be a computer readable storage medium.

The storage medium may be a U-disk, a removable hard disk, a Read-Only Memory (ROM), a magnetic disk, or an optical disk, or other various computer-readable storage media that can store program codes.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps described in connection with the embodiments disclosed herein may be embodied in electronic hardware, in computer software, or in a combination of the two, and that the elements and steps of the examples have been generally described in terms of function in the foregoing description to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of each unit is only one logic function division, and there may be another division manner in actual implementation. For example, multiple units or components may be combined or may be integrated into another system, or some features may be omitted, or not performed.

The steps in the method of the embodiment of the application can be sequentially adjusted, combined and deleted according to actual needs. The units in the device of the embodiment of the application can be combined, divided and deleted according to actual needs. In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The integrated unit may be stored in a storage medium if implemented in the form of a software functional unit and sold or used as a stand-alone product. Based on such understanding, the technical solution of the present application is essentially or a part contributing to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a terminal, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present application.

While the application has been described with reference to certain preferred embodiments, it will be understood by those skilled in the art that various changes and substitutions of equivalents may be made and equivalents will be apparent to those skilled in the art without departing from the scope of the application. Therefore, the protection scope of the application is subject to the protection scope of the claims.

Claims

1. A data storage management method, comprising the steps of:

analyzing key data of an operating system to obtain key data characteristics;

acquiring write data issued by a host;

judging whether the write data has the key data characteristics or not;

if the write data has the key data characteristics, judging the write data as the key data, improving the protection level of the write data and writing the data;

the step of analyzing the critical data of the operating system for critical data characteristics, comprising,

acquiring a data sector managed by an operating system;

identifying the position of a key sector where key data in the data sector are located;

analyzing the key sector to obtain the key guide sector position;

taking the key sector position and the key guide sector position as key data features;

wherein the critical data features refer to sector locations or ranges for storing critical data; the key sectors containing the key data are determined through analysis of the starting process of the operating system, the key sectors are further analyzed in a targeted manner, the key guide sector positions stored in the key sectors are further obtained, and the key sector positions and the key guide sector positions are used as key data features for evaluating the write data.

2. The data storage management method according to claim 1, wherein the step of judging whether the write data has the key data feature comprises,

analyzing the write data and obtaining LBA of the write data;

and judging whether the LBA of the write data is positioned in the key sector position or the key guide sector position.

3. The data storage management method according to claim 1, wherein the step of increasing the protection level of the write data and performing data writing comprises,

feeding back write data with key data characteristics to the SSDFTL;

adding management labels to the write data through SSDFTL to mark the protection level of the write data;

and according to the protection level of the write data, adopting a corresponding storage strategy to write the data.

4. The data storage management method as claimed in claim 3, wherein the step of performing data writing using the corresponding storage policy according to the protection level of the write data comprises,

writing the write data by adopting a high-level RAID storage strategy; or alternatively, the process may be performed,

simultaneously creating multiple data backups for the write data, and writing in; or alternatively, the process may be performed,

and dividing independent storage areas for writing the write data.

5. A data storage management apparatus, comprising:

the data acquisition unit is used for acquiring write data issued by the host;

the data writing unit is used for judging the write data as key data when the write data has key data characteristics, improving the protection level of the write data and writing the data;

the characteristic analysis unit comprises a sector acquisition module, a sector identification module, a sector analysis module and a characteristic acquisition module;

the sector acquisition module is used for acquiring a data sector managed by the operating system;

the sector identification module is used for identifying the position of a key sector where key data in the data sector are located;

the sector analyzing module is used for analyzing the key sector to obtain the position of the key guide sector;

the characteristic acquisition module is used for taking the key sector position and the key guide sector position as key data characteristics;

6. The data storage management apparatus according to claim 5, wherein the data judging unit includes a data analyzing module and an address judging module;

the data analysis module is used for analyzing the write data and obtaining LBA of the write data;

the address judging module is used for judging whether the LBA of the write data is located in the key sector position or the key guide sector position.

7. A computer device comprising a memory and a processor, the memory having stored thereon a computer program, the processor implementing the data storage management method according to any of claims 1 to 4 when executing the computer program.

8. A storage medium storing a computer program which, when executed by a processor, implements the data storage management method of any one of claims 1 to 4.