Multi-User Data Sharing Method, System, Electronic Device and Storage Medium

Abstract

An embodiment of the present application provides a multi-user data sharing method, system, electronic device and storage medium. The system includes N upper-layer file systems. The i-th user has read and write permissions for the i-th upper-layer file system, where 1 ≤ N and 1 ≤ i ≤ N; a lower-layer file system, and each user has only read permissions for the lower-layer file system; N combined mounting file systems, where the i-th upper-layer file system and the lower-layer file system corresponding to the i-th user are mounted on the i-th combined mounting file system. Among them, if a data reading instruction is received, the i-th upper-layer file system is preferentially accessed; if a data writing instruction corresponding to the lower-layer file system is received, the data corresponding to the data writing instruction is stored in the i-th upper-layer file system. In the embodiment of the present application, there is no need to copy the same copy in the storage spaces of each user, saving the storage space of users and not affecting the access of other users to the shared data.

Description

Technical Field

[0001] This application relates to the field of electronic technologies, and particularly to a multi-user data sharing method, system, electronic device, and storage medium. Background Art

[0002] In some application scenarios, data needs to be shared among multiple users. For this shared data, the access permission of the data needs to be set to read-only, otherwise user permission and data security issues will occur. If a certain user needs to modify the shared data, the shared data needs to be copied to their own storage space and modified within their own storage space. By using this method, the modified shared data will not affect the access of other users to the shared data, ensuring user permission and data security.

[0003] However, the above method requires copying the same copy in the storage spaces of each user, occupying a large amount of user storage space. Summary of the Invention

[0004] In view of this, this application provides a multi-user data sharing method, system, electronic device, and storage medium to facilitate solving the problem in the prior art that when writing to shared data, the same copy needs to be copied in the storage spaces of each user, occupying a large amount of user storage space.

[0005] In a first aspect, an embodiment of this application provides a multi-user data sharing system, including:

[0006] N upper file systems, each user corresponding to one of the upper file systems, where the i-th user has read and write permissions for the i-th upper file system, 1 ≤ N, 1 ≤ i ≤ N;

[0007] A lower file system, and each user has read-only permission for the lower file system;

[0008] N combined mounting file systems, each user corresponding to one of the combined mounting file systems, where the i-th upper file system and the lower file system corresponding to the i-th user are mounted on the i-th combined mounting file system;

[0009] Among them, the i-th combined mounting file system is configured to:

[0010] If a data reading instruction is received, the i-th upper file system is preferentially accessed;

[0011] If a data writing instruction corresponding to the lower file system is received, the data corresponding to the data writing instruction is stored in the i-th upper file system.

[0012] In a possible implementation, if a data reading instruction is received, the i-th upper file system is preferentially accessed, including:

[0013] If a data reading instruction is received and the data corresponding to the data reading instruction is stored in both the i-th upper file system and the lower file system, the data corresponding to the data reading instruction is read in the i-th upper file system.

[0014] In a possible implementation, the i-th combined mounted file system is further configured to:

[0015] If a data deletion instruction corresponding to the lower file system is received, the data corresponding to the data deletion instruction is marked in the i-th upper file system, and the data corresponding to the data deletion instruction is hidden in the i-th combined mounted file system through the marking.

[0016] In a possible implementation, it further includes:

[0017] N path mapping modules, where the i-th path mapping module is used to map the file path of the i-th combined mounted file system to the file path of the lower file system.

[0018] In a possible implementation, the path mapping module is a container.

[0019] In a second aspect, an embodiment of the present application provides a multi-user data sharing method, which is applied to the multi-user data sharing system according to any one of the first aspects above. The method includes:

[0020] If the i-th combined mounted file system receives a data reading instruction, the i-th upper file system is preferentially accessed;

[0021] If the i-th combined mounted file system receives a data writing instruction corresponding to the lower file system, the data corresponding to the data writing instruction is stored in the i-th upper file system.

[0022] In a possible implementation, if the i-th combined mounted file system receives a data reading instruction, the i-th upper file system is preferentially accessed, including:

[0023] If the i-th combined mounted file system receives a data reading instruction and the data corresponding to the data reading instruction is stored in both the i-th upper file system and the lower file system, the data corresponding to the data reading instruction is read in the i-th upper file system.

[0024] In a possible implementation, it further includes:

[0025] If the i-th combined mounted file system receives a data deletion instruction corresponding to the underlying file system, mark the data corresponding to the data deletion instruction in the i-th upper file system, and hide the data corresponding to the data deletion instruction in the i-th combined mounted file system through the marking.

[0026] In a possible implementation, it further includes:

[0027] Map the file path of the i-th combined mounted file system to the file path of the underlying file system.

[0028] In a third aspect, an embodiment of the present application provides an electronic device, characterized in that the electronic device is configured with the multi-user data sharing system according to any one of the first aspect.

[0029] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, characterized in that the computer-readable storage medium includes a stored program, wherein when the program runs, it controls the device where the computer-readable storage medium is located to execute the method according to any one of the first aspect.

[0030] The multi-user data sharing method provided by the embodiment of the present application has the following advantages:

[0031] 1) It is not necessary to copy the same copies in the storage spaces of each user, saving the user storage space, and multiple users have complete read and write permissions for the shared data, without affecting the access of other users to the shared data;

[0032] 2) Map the file paths of the combined mounted file systems of each user to the file paths of the same underlying file system, facilitating the rapid deployment of user services. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0034] Figure 1 It is a structural framework diagram of a combined mounted file system provided by an embodiment of the present application;

[0035] Figure 2 It is a framework diagram of a multi-user data sharing system provided by an embodiment of the present application;

[0036] Figure 3Schematic flowchart of a multi-user data sharing method provided by an embodiment of the present application. Detailed implementation manners

[0037] To better understand the technical solution of the present application, the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0038] It should be clear that the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application.

[0039] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "the" and "said" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0040] It should be understood that the term " / and / or" used herein is only an associative relationship describing associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0041] For the convenience of understanding, the concepts involved in the embodiments of the present application will be briefly introduced below.

[0042] Container:

[0043] A container is a lightweight, operating system-level virtualization technology that allows applications and their dependencies to run during resource isolation. All necessary components required to run an application are packaged into a single image, and this image can be reused. When the image runs, it runs in an independent environment and does not share the memory, CPU, or disk of the host operating system with other applications. This ensures that the processes within the container do not affect any processes outside the container. The biggest difference between a virtual machine and a container is that the container is faster and more lightweight - compared to a virtual machine running on top of a complete operating system, a container shares the operating system / kernel of its host.

[0044] Union mount:

[0045] A union mount file system is a stacked file system that depends on and is built on top of other file systems (such as ext4fs and xfs, etc.). It does not directly participate in the division of the disk space structure. Instead, it only "merges" different directories in the original underlying file system and then presents them to the user. Therefore, for the user, the content under the root directory of the union mount file system that they see comes from the "collection" of different directories specified during mounting.

[0046] See Figure 1 , which is a structural framework diagram of a union mount file system provided by an embodiment of the present application. Among them, the Merger Dir path is the file path of the union mount file system, and the Lower DirA path, Lower DirB path, and Upper Dir path are the file paths of other file systems. The user can mount the Lower DirA path, Lower DirB path, and Upper Dir path in the union mount file system, including the files and paths that the user wants to merge. The MergerDir path is the mount point. After the file system is mounted, the content from each of the LowerDirA path, Lower DirB path, and Upper Dir path will be seen simultaneously under the Merger Dir path, and the user also cannot (does not need to) perceive which of these files come from the LowerDir path and which come from the Upper Dir path. What the user sees is just an ordinary file system root path (the LowerDir path can have multiple or only one). For example, in Figure 1 , the files A, B, C, and D in the LowerDirA path, LowerDirB path, and Upper Dir path are merged into the Merger Dir path.

[0047] Although the union mount file system merges different layer paths, the Upper Dir path and each Lower Dir path are not completely equivalent and there is a hierarchical relationship. First, when there are files with the same name in the Upper Dir path and the Lower Dir path, the files in the Lower Dir path will be hidden, and users can only see the files from the Upper Dir path. Then, there is also the same hierarchical relationship among the Lower Dir paths, where the upper layer masks the files with the same name in the lower layer. For example, if there is a file B in both the Lower DirA path and the Upper Dir path, then the file B in the Upper Dir path will be merged into the Merger Dir path, and the file B in the Lower DirA path will be hidden. If there is a file C in both the Lower DirA path and the Lower DirB path, then the file C in the Lower DirA path will be merged into the Merger Dir path, and the file C in the Lower DirB path will be hidden. In addition, if there are paths with the same name, they will continue to be merged (the merger of the Lower Dir path and the Upper Dir path into the mount point path is a typical example of merging).

[0048] The Upper Dir path in each layer path is a readable and writable path. When a user writes data to a file from the Upper Dir path through the Merger Dir path, the data will be directly written to the original file under the Upper Dir path. The same applies to deleting files. The Lower Dir paths are read-only. After the union mount file system is mounted, no matter how the files or paths corresponding to the Lower Dir path in the Merger Dir path are operated on, the content in the Lower Dir path will not change at all.

[0049] In some file system architectures, the files in the above Lower DirA and Lower DirB paths can be used as shared data among multiple users, and the files in the Upper Dir path can be used as private data for a single user. Each user can read the files in the Lower DirA and Lower DirB paths through their respective Merger Dir paths. However, if a user needs to write data to the files in the Lower DirA and / or Lower DirB paths, the relevant files need to be copied to their own storage space, that is, the relevant files are copied to the Upper Dir path, and then data is written to the copied files. However, this method requires copying the same copies in the storage spaces of each user, occupying more user storage space.

[0050] In view of the above problems, the embodiments of the present application provide a multi-user data sharing system, which can not only ensure the uniqueness and security of shared data, but also minimize the storage space of users. The following is a detailed description with reference to the accompanying drawings.

[0051] Refer to Figure 2 , which is a framework diagram of a multi-user data sharing system provided by the embodiments of the present application. In Figure 2 , two users are taken as an example for illustration. It can be understood that those skilled in the art can configure 2 users or more users in the multi-user data sharing system according to actual needs, and the embodiments of the present application do not make specific limitations on this.

[0052] For the convenience of description, the two users are defined as the first user and the second user, and each user has a corresponding upper file system. The upper file system includes an upper file path and the files stored in the upper file path. For example Figure 1 the shown Upper Dir. Specifically, the first user corresponds to the first upper file system, which is the first user space, and the first user space stores the private data of the first user. Only the first user has read and write permissions for the first upper file system; the second user corresponds to the second upper file system, which is the second user space, and the second user space stores the private data of the second user. Only the second user has read and write permissions for the second upper file system.

[0053] The lower file system includes a lower file path and the files stored in the lower file path. For example, Figure 1 the described Lower DirA and Lower DirB. The first user and the second user share the lower file system, that is, the lower file system stores the shared data of the first user and the second user. Both the first user and the second user have only read permissions for the lower file system.

[0054] Mount the first upper file system and the lower file system at the mount point of the first user to obtain the first combined mount file system. For example Figure 1 the shown Merger Dir. The first user can read and write to the first upper file system and the lower file system through the first combined mount file system. Similarly, mount the second upper file system and the lower file system at the mount point of the second user to obtain the second combined mount file system. The second user can read and write to the second upper file system and the lower file system through the second combined mount file system.

[0055] According to the above description, the first user and the second user only have read permissions for the lower-level file system, and the first user and the second user cannot perform write operations on the lower-level file system. In order for the first user to have complete read and write permissions for the first jointly mounted file system; and the second user to have complete read and write permissions for the second jointly mounted file system. The embodiments of the present application configure the jointly mounted file system as follows:

[0056] 1) If a data reading instruction is received, the upper-level file system is preferentially accessed.

[0057] Specifically, if a data reading instruction is received and the data corresponding to the data reading instruction is stored in both the upper-level file system and the lower-level file system, the data corresponding to the data reading instruction is read in the upper-level file system.

[0058] It can be understood that if a data reading instruction is received and the data corresponding to the data reading instruction is only stored in the upper-level file system, the data corresponding to the data reading instruction is read in the upper-level file system; if a data reading instruction is received and the data corresponding to the data reading instruction is only stored in the lower-level file system, the data corresponding to the data reading instruction is read in the lower-level file system.

[0059] 2) If a data writing instruction corresponding to the lower-level file system is received, the data corresponding to the data writing instruction is stored in the upper-level file system.

[0060] For example, if the first jointly mounted file system receives a data writing instruction corresponding to the lower-level file system, the data corresponding to the data writing instruction (for the sake of convenience of explanation, this data is called data A) is stored in the first upper-level file system, that is, stored in the first user space. That is to say, in fact, data A is not written in the lower-level file system, but in the view of the first user, it has written data A in the corresponding file path. When reading data A, according to the rule in 1) above, the first user will first read data A stored in the first upper-level file system, and then read other data in the lower-level file system. Similarly, if the second jointly mounted file system receives a data writing instruction corresponding to the lower-level file system, the data corresponding to the data writing instruction is stored in the second upper-level file system, that is, stored in the second user space.

[0061] 3) If a data deletion instruction corresponding to the lower-level file system is received, the data corresponding to the data deletion instruction is marked in the upper-level file system, and the data corresponding to the data deletion instruction is hidden in the jointly mounted file system through the marking.

[0062] For example, if the first combined mounted file system receives a data deletion instruction corresponding to the lower-level file system, it marks the data corresponding to the data deletion instruction in the first upper-level file system. The marked content appears to be deleted in the first combined mounted file system and is invisible to the first user. In fact, the relevant content remains unchanged in the lower-level file system. Similarly, if the second combined mounted file system receives a data deletion instruction corresponding to the lower-level file system, it marks the data corresponding to the data deletion instruction in the second upper-level file system. The marked content appears to be deleted in the second combined mounted file system and is invisible to the second user. In fact, the relevant content remains unchanged in the lower-level file system.

[0063] Through the above configuration, the user has complete read and write permissions for its combined mounted file system. Since the data written to the lower-level file system is stored in the upper-level file system (i.e., the user space) and is invisible to other users, it will not affect the access of other users to the lower-level file system. That is to say, multiple users have complete read and write permissions for the shared data and will not affect the access of other users to the shared data.

[0064] It can be understood that the above combined mounted file system is embodied as a specified path in the user space. Due to the characteristics of the user space, the access paths of each user are not the same. For example, the first combined mounted file system is a specified path in the first user space; the second combined mounted file system is a specified path in the second user space.

[0065] In the scenario of multi-user service deployment, since the access paths of each user are not the same, it is necessary to perform personalized configuration for the services of each user (for example, adjust the corresponding data access path in the service), which increases the cost of service front-end deployment.

[0066] Based on this, on the basis of the above solution, the multi-user data sharing system provided in the embodiment of the present application further includes a path mapping module, which maps the file path of the combined mounted file system to the file path of the lower-level file system. For example, in Figure 2In the solution shown, the path mapping module is a container. Specifically, the first container maps the file path of the first union-mounted file system to the file path of the lower-layer file system; the second container maps the file path of the second union-mounted file system to the file path of the lower-layer file system. At this time, the service running in the container will access data from the virtual file path of the lower-layer file system existing in the container, and the file path of the lower-layer file system is perceived by the service as readable and writable and is the same as the file path of the lower-layer file system outside the container. And the modification footprint of the original data in the lower-layer file system is kept in the user space. For a multi-user service based on containers, it can be configured with a consistent shared data access path among various users, facilitating the service to be quickly and consistently deployed based on the containerization solution.

[0067] It can be understood that in addition to containers, the path mapping module can also be other service deployment tools, such as virtual machines, etc., and the embodiments of the present application do not make specific limitations in this regard.

[0068] It should be noted that Figure 2 only two users are taken as examples to illustrate the multi-user data sharing system, and the embodiments of the present application do not make specific limitations on the number of users in the multi-user data sharing system. For example, the number of users can be N, where N is any integer greater than or equal to 1. Among them, when the number of users is N, the number of upper-layer file systems, union-mounted file systems, and path mapping modules is also N, and there is a certain corresponding relationship among users, upper-layer file systems, union-mounted file systems, and containers. For example, the i-th user has read and write permissions for the i-th upper-layer file system; the i-th upper-layer file system corresponding to the i-th user and the lower-layer file system are mounted on the i-th union-mounted file system; the i-th path mapping module is used to map the file path of the i-th union-mounted file system to the file path of the lower-layer file system; 1 ≤ i ≤ N. Corresponding to the above embodiments, the embodiments of the present application also provide a multi-user data sharing method. This method can be applied to the above multi-user data sharing system, as Figure 3 shown, and mainly includes the following steps.

[0069] Step S301: If the i-th union-mounted file system receives a data reading instruction, it preferentially accesses the i-th upper-layer file system;

[0070] Step S302: If the i-th union-mounted file system receives a data writing instruction corresponding to the lower-layer file system, it stores the data corresponding to the data writing instruction in the i-th upper-layer file system;

[0071] Step S303: If the i-th combined mounted file system receives a data deletion instruction corresponding to the lower-layer file system, mark the data corresponding to the data deletion instruction in the i-th upper-layer file system, and hide the data corresponding to the data deletion instruction in the i-th combined mounted file system through the marking.

[0072] In a possible implementation manner, the above step S301 is specifically as follows: If a data reading instruction is received, and the data corresponding to the data reading instruction is stored in both the upper-layer file system and the lower-layer file system, read the data corresponding to the data reading instruction in the upper-layer file system. It can be understood that if a data reading instruction is received and the data corresponding to the data reading instruction is only stored in the upper-layer file system, read the data corresponding to the data reading instruction in the upper-layer file system; if a data reading instruction is received and the data corresponding to the data reading instruction is only stored in the lower-layer file system, read the data corresponding to the data reading instruction in the lower-layer file system.

[0073] In a possible implementation manner, the method further includes mapping the file path of the i-th combined mounted file system to the file path of the lower-layer file system.

[0074] For the specific content of the method embodiment of this application, reference can be made to the description of the above system embodiment. For the sake of brevity, it will not be elaborated here.

[0075] The multi-user data sharing method provided by the embodiments of this application has the following advantages:

[0076] 1) There is no need to copy the same copies in the storage spaces of each user, saving the user storage space, and multiple users have complete read and write permissions for the shared data, without affecting the access of other users to the shared data;

[0077] 2) Map the file paths of the combined mounted file systems of each user to the consistent file paths of the lower-layer file system, facilitating the rapid deployment of user services.

[0078] Corresponding to the above embodiment, the embodiments of this application also provide an electronic device, which is configured with the above multi-user data sharing system. The electronic device can be a terminal, a server, etc. The embodiments of this application do not limit the specific product form of the electronic device. It can be understood that generally, the electronic device includes a processor; a memory; and one or more computer programs, where the one or more computer programs are stored in the memory, and the one or more computer programs include instructions. When the instructions are executed by the terminal device, the electronic device executes some or all of the steps in the above method embodiment.

[0079] In a specific implementation, the present application further provides a computer storage medium. The computer storage medium may store a program which, when executed, may include some or all of the steps in the embodiments provided by the present application. The storage medium may be a magnetic disk, an optical disc, a read-only memory (ROM), a random access memory (RAM), or the like.

[0080] In a specific implementation, an embodiment of the present application further provides a computer program product. The computer program product includes executable instructions which, when executed on a computer, cause the computer to execute some or all of the steps in the above method embodiments.

[0081] In the embodiments of the present application, "at least one" means one or more, and "a plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B may indicate the case of A alone, A and B existing simultaneously, or B alone. Where A and B may be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one of the following" and its similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, and c may represent: a, b, c, a - b, a - c, b - c, or a - b - c, where a, b, and c may be single or multiple.

[0082] Those of ordinary skill in the art can realize that the units and algorithm steps described in the embodiments disclosed herein can be implemented by a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. A professional technician can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0083] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the above-described systems, devices, and units can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein.

[0084] In several embodiments provided by the present invention, if any function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0085] As described above, the foregoing is only a specific implementation manner of the present invention. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, and all such changes or substitutions should be covered by the protection scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A multi-user data sharing system, characterized in that, Including: N upper-level file systems, with each user corresponding to one upper-level file system. Among them, the i-th user has read and write permissions for the i-th upper-level file system, where 1 ≤ N and 1 ≤ i ≤ N; A lower-level file system, and each user has read-only permissions for the lower-level file system; N combined mount file systems, with each user corresponding to one combined mount file system. Among them, the i-th upper-level file system and the lower-level file system corresponding to the i-th user are mounted on the i-th combined mount file system; Among them, the i-th combined mount file system is configured as: If a data read instruction is received, it preferentially accesses the i-th upper-level file system; If a data write instruction corresponding to the lower-level file system is received, the data corresponding to the data write instruction is stored in the i-th upper-level file system; N path mapping modules, where the i-th path mapping module is used to map the file path of the i-th combined mount file system to the file path of the lower-level file system.

2. The multi-user data sharing system according to claim 1, characterized in that The "if a data read instruction is received, it preferentially accesses the i-th upper-level file system" includes: If a data read instruction is received and the data corresponding to the data read instruction is stored in both the i-th upper-level file system and the lower-level file system, the data corresponding to the data read instruction is read in the i-th upper-level file system.

3. The multi-user data sharing system according to claim 1, wherein The i-th combined mount file system is further configured as: If a data deletion instruction corresponding to the lower-level file system is received, the data corresponding to the data deletion instruction is marked in the i-th upper-level file system, and the data corresponding to the data deletion instruction is hidden in the i-th combined mount file system through the marking.

4. The multi-user data sharing system according to claim 1, wherein The path mapping module is a container.

5. A multi-user data sharing method, characterized in that, Applied to the multi-user data sharing system according to any one of claims 1-4, the method includes: If the i-th combined mount file system receives a data read instruction, it preferentially accesses the i-th upper-level file system; If the i-th combined mount file system receives a data write instruction corresponding to the lower-level file system, the data corresponding to the data write instruction is stored in the i-th upper-level file system.

6. The method according to claim 5, characterized in that, If the i-th combined mount file system receives a data read instruction, it preferentially accesses the i-th upper-level file system, including: If the i-th combined mount file system receives a data read instruction and the data corresponding to the data read instruction is stored in both the i-th upper-level file system and the lower-level file system, the data corresponding to the data read instruction is read in the i-th upper-level file system.

7. The method according to claim 5, characterized in that, It further includes: If the i-th combined mount file system receives a data deletion instruction corresponding to the lower-level file system, the data corresponding to the data deletion instruction is marked in the i-th upper-level file system, and the data corresponding to the data deletion instruction is hidden in the i-th combined mount file system through the marking.

8. The method according to any one of claims 5 to 7, characterized in that It further includes: Map the file path of the i-th combined mounted file system to the file path of the underlying file system.

9. An electronic device, characterized in that, The electronic device is configured with the multi-user data sharing system according to any one of claims 1-4.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein when the program runs, it controls the device where the computer-readable storage medium is located to execute the method according to any one of claims 5 to 8.

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