JPH03109653A - Initialization system for volume contents control table - Google Patents

Abstract

PURPOSE:To relieve a file despite the wrong initialization by saving the information at a fixed position with absence of an idle area of a volume which tries to initialize a volume contents control table available prior to the initialization of the control table or another idle area. CONSTITUTION:An idle area 15 includes an uninitialized volume contents control table 12 as well as an initialized volume contents control table 16. The table 12 stores the address information, the capacity, etc., of the files 13 and 14 which are available before initialization as they are. If a volume 11 is initialized by mistake, the accesses are given to both files 13 and 14 with use of the information saved in the table 12. Then the files 13 and 14 are copied to another volume. Thus it is possible to relieve the files so far available despite the wrong initialization.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for initializing a magnetic storage medium, and in particular, the present invention relates to a method for initializing a magnetic storage medium, and more particularly, to a method for initializing a magnetic storage medium, and in particular, a method for initializing a volume content, which comprehensively manages all files existing within a volume and free areas within the volume. Method for initializing management tables Conventional technology Conventionally, there are two methods for initializing magnetic storage media: one is to initialize a volume with no information written on the magnetic storage surface, and the other is to initialize a volume when some files already exist. A method is known in which only the volume content management table in which various information for managing these files is stored is initialized.

The latter method of initializing only the volume content management table does not physically erase all files that already exist in the volume, but logically erases only the file management information in the volume content management table. The feature is that the volume can be initialized by . File management information usually includes: (1) the location and size of the free area in the volume where no files exist; and (2) the name and location of each file in the volume (the beginning of each file. address and end address) and attribute information such as its size and file organization method. When file management information is initialized, all file name, location, and attribute information of each file existing in the volume are stored. The volume is logically erased, and free area information is also registered as if the entire volume was logically empty.

Problems to be Solved by the Invention Therefore, when the volume content management table is initialized, the means for confirming the location of files existing in the volume, the file attribute information, etc. are lost, and the files remaining in the volume are lost. Initialization is achieved by bringing the situation to the same level as logically annihilating it.

On the other hand, in the unlikely event that an unintended volume is initialized by mistake, the information that manages the files will be lost, so it is logical to rescue the files that previously existed. It becomes impossible.

The present invention has been made in view of the above-mentioned conventional situation,
Therefore, an object of the present invention is to solve the above-mentioned problems inherent in the prior art, and to solve the above-mentioned problems inherent in the prior art, and to provide a free area or an empty area of a volume in which a pre-existing volume content management table is to be initialized prior to the initialization of the volume content management table. A new technology that makes it possible to easily obtain information related to file rescue in the event that an unintended volume is accidentally initialized by saving it to a predetermined location when the area does not exist. The objective is to provide a volume management method.

Means for Solving the Problems In order to achieve the above object, the volume content management table initialization method according to the present invention uses an already existing volume content management table for the volume, prior to initializing the volume content management table. a first step of saving in a free area or, if there is no free area, in a fixed position within a predetermined volume;
and a second step of initializing the volume content management table after the save in the step is completed.

Embodiments Next, preferred embodiments of the present invention will be specifically explained with reference to the drawings.

FIG. 1 is a flowchart showing one embodiment of the steps of the volume initialization method according to the present invention.

Referring to Figure 1, first, in step 1, the volume content management table indicated by the current pointer on the volume label is read out.Next, in step 2, it is determined whether there is an area in the volume to save the volume content management table. investigate. If there is an area to save in step 3, the volume content management table is stored in a free area in step 4. If there is no free area, the volume content management table is stored in a predetermined volume content save area in step 5.

Next, in step 6, the old pointer on the volume label is updated with the start address of the saved volume content management table. Subsequently, in step 7, the volume content management table is initialized.

FIG. 2 shows the initialized volume content management table 12 of the volume 11 and the file 1 existing in the volume 11.
3 is a diagram illustrating an example of a state of a certain volume composed of a file 14 and a file 14. FIG.

At this time, the pre-initialization volume content management table 12 is as follows:
It is assumed that address information, capacity, file attribute information, etc. regarding files 13, 14, and free area 15 are managed.

In this state, the pre-initialization volume content management table 12
When initialized using the conventional method, as shown in FIG. 3, logically only a new initialized volume content management table 16 exists within the volume, and files 13 and 14 are logically volume 11
disappears from the volume content management table 1 after initialization.
6 is in a state where only the information whose entire volume is an empty area is managed.

According to the method of the present invention, as shown in FIG. 4, in addition to the post-initialization volume content management table 16 shown in FIG. There is. The pre-initialization volume content management table 12 holds the address information, capacity, file attribute information, etc. of the files 13 and 14 that existed before initialization as they are.

Therefore, even if you accidentally initialize the volume 11, if it is immediately after initialization, the file 11
It can be easily rescued by accessing the file 14 (since it has not physically disappeared) and moving it to another volume.

FIG. 5 is a diagram showing a configuration example of the volume label 18 having address pointer information of two volume content management tables of the volume 11.

Referring to FIG. 5, the volume label 18 includes two volume content management tables existing in the volume 11, namely, a current pointer 19 which is an address pointer for the post-initialization volume content management table 16, and a current pointer 19 which is an address pointer for the post-initialization volume content management table 16; It has an old pointer 20 which is an address pointer for the volume content management table 12.

In the case of normal file access, the current pointer 19 is followed, and in the case of file access to rescue a file that has been initialized by mistake, the old pointer 20 is followed, and the two volume content management tables 16
and 12, it is possible to access files that are logically manifest or latent within the volume.

As described in detail, according to the present invention, when initializing a volume, especially initializing a volume content management table, is performed on an unintended volume, files existing in the volume can be initialized. Immediately after conversion, it is possible to save all files without damaging them.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing an embodiment of the process of the volume content management table initialization method according to the present invention, and FIG. 2 is a flowchart showing an example of the steps of the volume content management table initialization method according to the present invention. A schematic diagram showing an example of one state of a volume. FIG. 3 is a schematic diagram showing an example of one state of a volume for explaining the prior art. FIGS. 4 and 5 are a schematic diagram showing an example of one state of a volume for explaining the present invention. FIG. 2 is a schematic diagram illustrating an example. 11...Volume, 12...Pre-initialization volume content management table, 13.14...File, 15.
...Free area, 16...Volume content management table after initialization, 18...Volume label, 19...
Current pointer, 20...old pointer

Claims (3)

[Claims] (1) A method of initializing only a volume content management table in a magnetic storage medium, and prior to initializing the volume content management table, a copy of the volume content management table that already exists is transferred to an empty area within the volume. The method for initializing a volume content management table is characterized in that it includes means for saving in a certain area within a predetermined volume when there is no free area. (2) An old address pointer indicating the location of the volume content management table before initialization to be saved, and a current address pointer indicating the location of the newly initialized volume content management table after initialization. The volume content management table initialization method according to claim 1, further comprising: a volume content management table initialization method. (3) means for reading the volume content management table before initialization that is saved when the volume content management table is initialized by mistake; and a means for temporarily reading out the volume content management table before initialization that has been read out. 2. A storage device for storing a pre-initialized volume management table stored in the storage device on a post-initialized volume content management table. The volume content management table initialization method described in 1) or (2).