JP2000155707A - File system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a file system which exerts no influence on other terminals even when respective terminals operate data on a file server by managing the terminals sharing the data on the file server. SOLUTION: A logical layer management part 104 which relates a logical layer used for access from a user terminal to the hierachical structure of data files on the file server is provided on the user terminal 102. Consequently, the user terminal is able to access data without considering the hierarchical structure of the data files on the file server. On the user terminal (anywhere in the system), data position management tables 1201 to 1203 stored with the number of logical layers which were referred to are provided by data, and the tables are referred to when the data are accessed to prevent the storage capacity on the file server from being wasted owing to the repetitive storage of data and a logical layer having no reference destination from being generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file system provided with a file server for storing data and providing the data to a use terminal, and more particularly to a file system which is connected to a plurality of terminals via a network and receives requests from individual terminals. Accordingly, the present invention relates to a file system including a file server for providing data.

[0002]

2. Description of the Related Art Generally, a file system on a file server manages data in the file system.
A hierarchical structure using logical names is constructed in the file system, and all data to be managed are hierarchically managed.
Data is managed including which logical layer it belongs to in the file system. To access data on a file server, search the logical hierarchy to which the data belongs from the entire logical hierarchy on the file system, and then access data with a matching data name in that hierarchy. Is done by the method.

[0003] In the file server data as described above,
When accessing from a use terminal on a network, data is often shared by sharing the data on the file server with the terminal. Such a technique is known as Sun Microsyste
Network file system proposed by ms (NF
S), it is possible to use a technique known as file sharing in Microsoft Windows.

[0004] Specifically, in the above-described technique, in the file server, for each logical layer on the file system to which the data to be shared belongs, the connection is made to a certain logical layer or lower in the file system of the use terminal. In the case of using this technology, the terminal accesses to a layer lower than the layer connected to the terminal in use as if it were a logical layer under the management of the file system of the terminal itself. In practice, this is done by accessing a logical hierarchy under the management of the file system on the file server.

The operation of connecting the logical hierarchy of another file system to one logical hierarchy or lower of the own system as described above is called a mount, and is effective when data is shared for each hierarchy. As a conventional technique for extending such a technique to mount a logical hierarchy of another file system and construct an arbitrary hierarchical structure for each user, for example, a technique described in JP-A-6-149633 or the like is known. Are known.

In the above description, when data on a file server is shared by a plurality of terminals, all terminals connect the file data hierarchy on the file server to be shared by each terminal, so that all terminals It becomes possible to access the above data.

[0007]

In the above-described file system according to the prior art, when accessing data on a file server, the data is accessed based on the logical hierarchy of the file system.
The following problems occur.

In other words, according to the above-mentioned prior art, when accessing the same data from a plurality of logical hierarchies on a file system, the data must be stored at a plurality of locations associated with the respective logical hierarchies. As a result, there is a problem that the secondary storage device is wasted.

In the above-mentioned conventional technology, when one logical layer is mounted on a different logical layer of a terminal to be used in a file system on a server, the logical layer is mounted via one logical layer. When the structure of the logical hierarchy is changed, there is a problem that the other logical hierarchy is also changed.

[0010] Further, in the above-mentioned conventional technology, when one logical layer is mounted on a different logical layer of a user terminal in the file system on the server, the data on the file server is transmitted via one logical layer. Is deleted, the data on the other logical layer is also deleted.

An object of the present invention is to solve the above-mentioned problems of the prior art, and does not allow a use terminal to directly access a logical hierarchy of a server when accessing data on a file server (server side). By not knowing the logical hierarchy of the file server) and managing from which terminal the data on the file server is shared, it is possible to prevent each use terminal from affecting other terminals To provide a file system.

[0012]

According to the present invention, the above object is achieved by connecting one or a plurality of file servers, one or a plurality of file servers, and one or a plurality of use terminals via a network, and In a file system in which a terminal accesses data in a file server, a data location management table in which a logical name including a hierarchical structure of an existing data file is described for each data, and a logic including an arbitrarily constructed hierarchical structure The file server has a logical location management table for associating a name with a corresponding data location management table, and the file server hierarchically manages all data managed by itself, including the logical hierarchy name to which the data belongs. The data is stored by linking the physical name of the data to the logical name including the logical hierarchy name to which the data belongs. Having a data file, in response to a request from the use terminal, accessing the requested data by a logical name on the data file, and the use terminal This is achieved by referring to the two tables and requesting access to data on the file server.

[0013] Further, the object is that the data location management table is a reference counter which indicates that each logical name on an existing data file is associated with a plurality of logical names in an arbitrarily constructed hierarchical structure. Achieved by holding the value.

Further, the object is to add or delete an arbitrarily constructed hierarchical structure or to edit data in an existing data file based on a logical name in the arbitrarily constructed hierarchical structure. This is achieved by determining whether data can be added, deleted, or edited based on the reference counter value held in the data position management table.

According to the present invention, a logical hierarchical structure is constructed by using the two tables of the data position management table and the logical position management table described above, and data on a file server is accessed using only logical names. It is possible to do. Also, by recording in the data location management table how many logical names in the newly created logical hierarchical structure correspond to the data described in the table, the data from one logical name can be stored. It is possible to prevent the change from affecting the other logical name.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a file system according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a file system according to an embodiment of the present invention, FIG. 2 is a diagram for explaining the configuration of a logical location management table stored in a logical hierarchy management unit in FIG. 1, and FIG. FIG. 4 is a view for explaining an example of a data position management table referred to when the created logical layer accesses data, and FIG. 4 is a view for explaining an example of a GUI for displaying the hierarchical structure of the created logical layer. 1 to 3, 101 is a monitor, 102 is an operation terminal, 103 is a memory, 104 is a logical hierarchy management unit, 111 to 113 are file servers, 120 to 123 are secondary storage devices, 120
1 to 1203 are data position management tables, and 1204 is a logical position management table.

As shown in FIG. 1, a file system according to an embodiment of the present invention includes a plurality of file servers 111.
To 113 and the operation terminal 102 are connectable via a network. File server 111-1
13 includes secondary storage devices 121 to 123 each storing a data file for constructing a file system, and the operation terminal 102 includes a secondary storage device 120, a monitor 101, and a logical hierarchy management unit 104. Is stored in the memory 103. The secondary storage devices 120 to 123 provided in the operation terminal 102 and the file servers 111 to 113 are configured by hard disk devices and the like, and are indicated as HD0 to HD3 in FIG. The secondary storage device 120 of the operation terminal 102 stores data location management tables 1201 to 1203 and a logical location management table 1204.

In the embodiment of the present invention shown in FIG. 1, only one operation terminal 102 is shown connected to the network. However, a plurality of operation terminals can be connected to the network. . Although the embodiment shown in FIG. 1 shows that the data location management tables 1201 to 1203 are provided in the operation terminal which is a use terminal, the data location management table may be provided anywhere in the system if only one is provided. May be.

In the file system according to the embodiment of the present invention described above, when the operation terminal 102 is activated,
The logical hierarchy management unit 104 in the memory 103 reads the logical position management table 1204 in the secondary storage device 120. Next, the logical tier management unit 104
0, using the data location management tables 1201 to 1203 in the file server 111 to the operation terminal 102.
It performs mapping between the hierarchical structure of its own file system and the logical hierarchical structure created by the file system. The monitor 101 displays the newly created logical hierarchical structure. The user of the operation terminal operates the logical hierarchical structure displayed on the monitor 101, and accesses data stored in the secondary storage devices 120 to 123 corresponding to the operation.

Next, a procedure for creating a logical hierarchical structure constructed by the file system of the present invention as shown in FIG. 4 in the above-described file system will be described with reference to FIGS.

The logical hierarchy management unit 1 in FIG. 1 shown in FIG.
In the example of the logical position management table 1204 stored in the table 04, one row of the table indicates a set of logical layers. The column 201 is a logical hierarchy structure arbitrarily created by the file system, and records all hierarchies from the highest hierarchy to the designated logical hierarchy. A column 202 is a logical hierarchy located one level lower than the logical hierarchy of the column 201, and a column 203 indicates the position of a data position management table used when the logical hierarchy of the column 201 is associated with data. I have.

FIG. 3 shows an example of a data position management table referred to by the column 203 in FIG. 2, and there is one data position management table for one data. The column 301 of the data position management table stores, as a reference counter, the number of logical hierarchies that refer to this data among the logical hierarchies created according to the present invention. This reference counter is used when adding or deleting an arbitrarily constructed hierarchical structure or when editing data in an existing data file based on a logical name in an arbitrarily constructed hierarchical structure. , Delete, edit. The column 302 stores the position of the data on the file system of the file server storing the data.

GU displayed on monitor 101 shown in FIG.
The example of I is an example of displaying based on the contents of the management tables shown in FIGS. 2 and 3. The logical hierarchy shown by the column 201 in FIG. 2 is divided into all the layers up to that level. A hierarchical structure is constructed. It is assumed that a logical layer in which all layers up to that layer are the same is located immediately below the same layer. Then, a hierarchical structure is constructed such that the logical hierarchy shown in the column 202 of FIG. 2 is placed immediately below the logical hierarchy shown in the column 201 of FIG.

In the example shown in FIG.
0 is located at the top of the hierarchical structure, and Folders 401 to 4
03 is in the lower level. Further, the Folder 401 has Sub Folders 411 to 413 at the lower level.
411 has Data 421 to 423 below it. Da
For access to ta 421 to 423, a target logical name is searched from the upper level to the lower level of the hierarchical structure, and the position of the data position management table corresponding to the logical name is set in column 20 of FIG.
3 is obtained. Further, the position of the data on the file server is known from the column 302 in FIG.

In the above description, a plurality of file servers are connected via a network.
The present invention can be applied to a case where the use terminal itself is a file server and there is no other file server. In this case, the data position management table in the column 203 shown in FIG. 2 and the data position management table shown in FIG. The operation itself is not different from the above-described example, only the position of the data of the column 302 to be operated is the position managed by the file system of the use terminal.

Next, a description will be given of a processing operation when changing the logical hierarchical structure created in the file system according to the embodiment of the present invention configured as described above.

FIG. 5 is a flow chart for explaining the flow of processing when newly registering logical data. This will be described below.

(1) When newly registering a logical name, a logical hierarchy related to data stored in the file server,
Root Folder 400, Folders 401 to 4 in FIG.
03, there are logical hierarchies that are not directly related like SubFolders 411 to 413, and it is necessary to classify the registration methods of both, so first, the logical name to be newly registered is stored in the file server. It is determined whether there is a relationship with the data (steps 501 and 502).

(2) If it is determined in step 502 that the logical name to be newly registered is related to the data stored in the file server and that it is necessary to perform the association, the logical position management table 1204 is accessed. Then, it is checked whether or not the data position management table corresponding to the data already exists, and it is determined whether or not the data is data already associated with another logical hierarchy (step 503, 504).

(3) If it is determined in step 504 that the data is data already associated with another logical hierarchy, the data position management table is updated by incrementing the reference counter in the data position management table by one. Is performed (step 505).

(4) If it is determined in step 504 that the data is not data already associated with another logical hierarchy, a data position management table is newly created and its reference counter is set to 1. Then, the data and the data position management table are newly registered (steps 506 and 507).

(5) If the data location management table is updated in step 505, if it is determined in step 502 that the logical name to be newly registered is not related to the data, and if When the data position management table and the data position management table are newly registered, they are registered in the logical position management table (step 508).

FIG. 6 is a flowchart for explaining the flow of processing when deleting a logical hierarchy. This will be described below.

(1) In the case of deleting a logical name, first, it is checked whether there is a data location management table corresponding to the logical name to be deleted, in order to consider the influence on other logical hierarchies. It is determined whether or not there is a relationship between the logical name to be executed and the data stored in the file server (step 601,
602).

(2) If there is a data position management table corresponding to the logical name to be deleted in step 602, processing is performed on the data position management table described later with reference to FIG. 7 (step 603).

(3) If there is no data position management table corresponding to the logical name to be deleted in step 602,
It is determined whether or not a logical name exists in a lower logical layer of this logical name. If a logical name exists in the lower logical layer, the step of FIG. The process of deleting the logical name from the 601 is performed (step 604).

(4) After the processing in step 605, and when the logical name does not exist in the lower logical hierarchy in step 604, the logical name is deleted from the logical position management table (step 606).

FIG. 7 is a flowchart for explaining the flow of processing for the data position management table in the above-mentioned step 603, which will be described below.

(1) When data referred to by a logical layer to be deleted also refers to another logical layer, if data is deleted on one logical layer, another logical layer should be referred to. In order to avoid this, since the data does not exist, when this processing is started, first, the logical position management table is accessed to obtain the data position management table of the data related to the logical name to be deleted. (Steps 701 to 703).

(2) By checking the value of the reference counter in the acquired data position management table, it is determined whether or not the data referenced by the logical name to be deleted also refers to another logical name (step). 704).

(3) In step 704, if the value of the reference counter is 2 or more and the data referenced by the logical name to be deleted also refers to another logical name, the value of the reference counter is changed. The processing is terminated by reducing the number by one (step 70)
5, 707).

(4) In step 704, the data position management table and the data position management table are determined on the assumption that the data referenced by the logical name to be deleted does not have a reference from another logical layer. The data on the file server is deleted, and the process ends (steps 706 and 707).

FIG. 8 is a flowchart for explaining the flow of processing at the time of editing data linked to the logical name referred to by the logical hierarchy. This will be described below.

(1) Access the logical position management table to obtain a data position management table corresponding to the data to be edited (steps 801 to 803).

(2) Whether or not the data referred to by the original logical layer is referred to by another logical layer is confirmed by the value of the reference counter. If the value of the counter is 1 and is not referenced from any other logical layer, the data is saved in the file system on the file server under the same name as before editing (steps 804 and 805).

(3) In step 804, if the value of the counter is 2 or more and is referenced from another logical hierarchy, the value of the reference counter of the data position management table corresponding to the data before editing is reduced by one. The edited data is stored under another name (steps 806 and 807).

(4) Next, a new data position management table corresponding to the data is created on a one-to-one basis. Further, of the entries of the logical position management table, the column 203 in FIG. Rewrite with the table name (steps 808, 809).

FIG. 9 is a flowchart for explaining the flow of processing when copying a logical name of a logical hierarchy. This will be described below.

(1) First, it is determined whether or not a data position management table corresponding to the target logical name exists. If so, the logical position management table is accessed to access the data position management table corresponding to the data. Are acquired (steps 901 to 904).

(2) In the copy process, since there is no need to move data on the file server, the reference data of the data location management table of the associated data is increased by one, and then the logical location management table entry is added. (Steps 905 and 906).

(3) If there is no data position management table corresponding to the target logical name in step 902, an entry is added to the logical position management table (step 906).

(4) Next, it is checked whether or not a logical name exists below the logical name of the copy source. If a logical hierarchy exists below the logical name, all the lower logical hierarchies are replaced with the hierarchical structure. While maintaining, the copy is performed below the copied logical layer and the process is terminated (steps 907 to 909).

FIG. 10 is a flowchart for explaining the flow of processing when moving the logical name of a logical hierarchy. This will be described below.

(1) First, the process described with reference to FIG. 9 for copying the source logical name to the destination logical name is performed, and the moved logical hierarchy is registered in the logical position management table (steps 1001 and 1002). ).

(2) Deleting the source logical name The process described with reference to FIG. 6 is performed, the logical hierarchy before the transfer is deleted from the logical location management table, and the process ends (step 1).
003, 1004).

In the above-described embodiment of the present invention, since the data on the data management file server is accessed by combining the logical location management table and the data location management table, the data is stored on the file server. When data is accessed, it is not necessary to consider the hierarchical structure of the file system of the file server in which the data is stored.

Further, the above-described embodiment of the present invention can be applied to a case where the newly created logical hierarchies belonging to different hierarchies of the logical hierarchies refer to the same data on the file server. Therefore, it is not necessary to store a plurality of data at the locations referred to by the respective logical hierarchies, and waste of the secondary storage device can be prevented.

Further, according to the embodiment of the present invention, in the above-described case, the processing of editing or deleting the logical hierarchy of one hierarchical structure does not affect the other hierarchical structure at all, and the logical hierarchy of the other hierarchical structure is not affected. Since the movement is completed only by changing the logical location management table, the processing can be completed at high speed without affecting the hierarchical structure in the file server.

[0060]

As described above, according to the present invention, it is possible to manage from which terminal the data on the file server is shared, so that each use terminal has an effect on other terminals. Can not be.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a file system according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a logical position management table stored in a logical hierarchy management unit in FIG.

FIG. 3 is a diagram illustrating an example of a data location management table referred to when a created logical hierarchy accesses data.

FIG. 4 is a GU displaying a hierarchical structure of a created logical hierarchy;
FIG. 9 is a diagram for explaining an example of I.

FIG. 5 is a flowchart illustrating a flow of processing when newly registering logical data.

FIG. 6 is a flowchart illustrating a flow of processing when deleting a logical hierarchy.

FIG. 7 is a flowchart illustrating a flow of processing for a data position management table in step 603 described above.

FIG. 8 is a flowchart illustrating a flow of processing when editing data linked to a logical name referred to by a logical hierarchy.

FIG. 9 is a flowchart illustrating a flow of processing when copying a logical name of a logical hierarchy.

FIG. 10 is a flowchart illustrating a flow of processing when a logical name of a logical hierarchy is moved.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Monitor 102 Operation terminal 103 Memory 104 Logical hierarchy management unit 111-113 File server 120-123 Secondary storage device 1201-1203 Data location management table 1204 Logical location management table

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Masaru Igawa 810 Shimo-Imaizumi, Ebina-shi, Kanagawa Prefecture Inside of Hitachi, Ltd.Server Development Division (72) Inventor Mihiro Takiyasu 810 Shimo-Imaizumi, Ebina-shi, Kanagawa Prefecture F-term in Hitachi Server Development Division (Reference) 5B045 DD15 DD16 5B082 EA02 FA05 FA16 5B089 GA11 GA21 JA32 KA11 KA12 KC14 KC15 KC41 KC51 KC60

Claims (3)

[Claims] In a file system in which one or a plurality of file servers and one or a plurality of use terminals are connected via a network, and the use terminals access data in the file server, a hierarchy of existing data files is provided. A data position management table describing a logical name including the structure for each data, and a logical position management table for associating the logical name including the arbitrarily constructed hierarchical structure with the corresponding data position management table, The file server manages all data managed by itself in a hierarchical manner including a logical hierarchy name to which the data belongs, and a logical name including a logical hierarchy name to which the data belongs,
A data file storing the data by linking the physical positions of the data, and accessing the requested data by a logical name on the data file in response to a request from the use terminal; A file system, wherein the terminal requests access to data on a file server by referring to the two tables based on an arbitrarily created logical name. 2. The data position management table holds a reference counter value indicating that each logical name on an existing data file is associated with a plurality of logical names in an arbitrarily constructed hierarchical structure. 2. The file system according to claim 1, wherein: 3. The method according to claim 1, wherein when adding or deleting an arbitrarily constructed hierarchical structure, or when editing data in an existing data file based on a logical name in the arbitrarily constructed hierarchical structure. 3. The file system according to claim 2, wherein whether to add, delete, or edit data is determined based on a reference counter value held in the management table.