JPH03131942A - File managing system - Google Patents

Abstract

PURPOSE:To simplify the control method of files by storing the using information of a data block storing files in a controlling data block as an allocation vector and setting up its block number in a directory. CONSTITUTION:In the case of newly writing a file existing in a memory in an HDD 5, a CPU 1 searches a directory area residing in a control buffer 4 similar to that in the HDD 5, acquires an idle directory and sets up a file name and a type. Then the CPU 1 regards an idle data block as a controlling data block and sets up its data block number and field number in the directory. When the idle data block is specified, the contents of the file are written and its corresponding data block number is set up in the field of the controlling data block as an allocation vector. After completing the writing of the file, the controlling data block is written in the HDD 5 and the directory in the buffer 4 is written in the HDD 5 to complete the processing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a file management method in an auxiliary storage device such as a computer system and a communication control device.

[Conventional technology]

Figure 4 is auxiliary memory! 1 is a configuration diagram of a computer system having a CPU.

(2) indicates the main memory (Memo!J), +a+ indicates a control unit (DMA) that performs DMA transfer of data between the control buffer memory (41) and the auxiliary storage device ((HDD) (51).

For example, Figure 5 is from Microcomputer Research Special Feature CP/M Utilization Technology (CQ Publishing 19115 No.

16) shows the structure of the conventional directory and PCB (file management block) shown in FIG.

Next, the operation will be explained.

When writing a new file to file 1 HDDI51 that exists on memory (21), CPUfil is
The directory area within is transferred to the control buffer (4) via DMAf31, and this is searched to secure an empty directory. At this time, note January 2) on the new PCB.
(File storage block) is created. Next, specify an empty data block and copy the contents of the file on memory +21 to the 1m buffer (4)L, DMA +s+
, and set the corresponding data block number in the PCB. (Figure 5) If the contents of the file cannot be written in one data block.

Specify yet another empty data block and move it to the HDD (5
Set the write data block number 1FcB to 1. If files cannot be written using one PCB, search further directory areas and create an empty directory Y.
t is secured and the above process is repeated. After writing all the contents of the file, copy the PCB created on the memory (2) to the control buffer (4) L, and drive it to the HDD via DMA +3+.
Transfer to the directory area in f51.

The format of the directory at this time is shown in FIG.

[The problem that the invention attempts to solve]

Conventional file management systems are structured as described above, so 1. For example, the size of a data block is set to 8 bytes,
If the disk capacity is 255 data blocks or more,
Assuming all 1MB file accesses, 1
Because 6 FCBk are required, the number of searches for empty directories in the directory area increases, and the PCB consisting of 32 bytes increases. When trying to access a large number of files, there was a problem that it was inefficient and took an hour for devices that required high-speed access.

This invention was made to solve the above-mentioned problems, and in systems where the maximum file length is fixed, it is possible to efficiently (and speed up) access to and from the auxiliary storage device. , the purpose is to obtain a file management method that can simplify the directory structure.

[Means to solve the problem]

The file management method according to the present invention uses some of the data blocks conventionally used to store files as management, divides these into a plurality of fields, and stores the data actually stored in the file. The block usage information is used as an allocation vector, and the management data block number and block field number are used as directory entries.
This is a directory structure with a size of 1 (16 bytes) for the CP/M directory.

[Effect]

The file management method of the present invention effectively speeds up access to the auxiliary storage device and improves processing performance by simplifying directory management.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a directory configuration diagram according to the present invention.
In the figure, the file name and type are the same as before.
The management data block number shown in FIG. 2 is set as the data block number. Also, data
The field number in the management data block shown in FIG. 3 is set as the block field number.

FIG. 2 shows a directory area and a data block area in the auxiliary storage device. FIG. 3 shows the configuration of the management data block, and the field in use indicates $, in which data block numbers in which data are stored are set in order. FIG. 4 is the same as the conventional example.

Next, the operation will be explained.

When writing a new file to the HDD +5+ from a file existing on the memo (January 2), the CPUTl+ uses the control buffer (
4) Search for a directory area similar to that in the HDDf51 resident in the HDD, obtain an empty directory, and set the file name and type. Next, the empty data block is set as a management data block and its data block number and field number are set in the directory. (Figure 1) After that, specify an empty data block and fold the contents of the file.

The corresponding data block number is set as an allocation vector in the management data block field. If you cannot write to a file or one data block, use JI! Specify the primary empty data block and write the file contents.

Set the corresponding data block number in the management data block and repeat the process. Here, the field supplied by the allocation vector ta of the management data block is set to be larger than the maximum length of the file, so the entire file can be stored in one management data block. . When the above process completes the file convolution, the W fence data block is
Convolution 1 is then applied to the DDf51, and the directory in the control buffer set at the time of file creation is written to the directory area in the HDDf51, completing the process.

〔Effect of the invention〕

As described above, according to the present invention, usage information of a data block storing a file is stored as an allocation vector in a management data block, and the block number? The code set in the directory effectively speeds up access to the auxiliary storage device, and also halves the size of the directory, which has the effect of simplifying the management method.

[Brief explanation of the drawing]

FIG. 1 is a directory configuration diagram according to an embodiment of the present invention, FIG. 2 is a diagram showing a directory area and a data block area in an auxiliary storage device, and FIG. 3 is a diagram showing a management data block area.
FIG. 4 is a block diagram of the configuration of Synutem, and FIG. 5 is a diagram of the directory configuration in CP/M. In the figure, (1) is CPU, 121iJ is memory,
(3) shows a DMAII control section, C4) shows a control buffer memory, and C5) shows an auxiliary storage device. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] A file management method for an auxiliary storage device, characterized in that usage information of a data block storing a file is stored in a block along with management data, and this is set in a directory.