JP3212668B2 - Virtual disk unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a virtual disk device for writing and reading a record to and from a region corresponding to a track in a storage region of a semiconductor storage unit, similarly to a magnetic storage device.

[0002]

2. Description of the Related Art Conventionally, in this kind of virtual disk device,
When a record is accessed, the entire track in which the record is stored is read, and the record is searched for in the track.

[0003]

The above-mentioned conventional virtual disk device has the following problems. Since the entire track is read, the transfer amount becomes large and the transfer time becomes long, and the buffer area required for the transfer becomes large. It takes time to search the entire track for records.

[0004] The present invention has been made in view of the above problems, and has as its object to provide a virtual disk device capable of shortening an access time and reducing a storage area.

[0005]

SUMMARY OF THE INVENTION A virtual disk device according to the present invention stores at least one or more physical records.
Physical record storage area and whether the physical record is valid
Valid flag indicating whether or not in the physical record track
In-track displacement showing relative displacement at the physical record
Access length including the physical record length indicating the record length of the
Access information file that stores access information for each physical record.
Half with a virtual disk containing tracks consisting of storage areas
And the conductor storage device, a logical record output means for obtaining a physical record address of the semiconductor memory device and in the semiconductor memory device output requested logical record exists,
Physical record input / output means for determining whether the input / output request is an input / output request for the virtual disk; and if the input / output request is an input / output request for the virtual disk, the physical record address The semiconductor record address of the track where the physical record exists is calculated from the cylinder number and the track number of the physical record, and the physical record is calculated from the semiconductor memory address of the track where the physical record exists and the physical number in the physical record address. calculate the semiconductor memory device the address of the access information corresponding enter the access <br/> scan information corresponding to the physical records in the contained <br/> access information corresponding to the physical record entered When the valid flag is valid, the track in which the physical record exists is located in the semiconductor storage device. The semiconductor memory device the address of the physical records from the track in the displacement calculated contained in accession <br/> Seth information corresponding to the address physical disks, the physical
Performs input and output of the physical record as the transfer length the physical record length included in the access information corresponding to the record, the virtual disk output means for notifying the result of the input and output the physical records to the physical record output means Wherein the physical record input / output means receives a notification of the result of input / output of the physical record, and notifies the logical record input / output means of a result of input / output of the physical record. The logical record input / output means receives a notification of the result of input / output of the physical record, and returns the logical record to the input / output request source of the logical record in the case of an input request, and returns the logical record in the case of an output request. Is characterized by returning the result.

[0006]

According to the first aspect of the present invention, at the time of accessing a record, the access means reads an access information storage area which holds a storage state of the record in the track, and sets a storage area of a necessary record. Access the record after requesting.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a virtual disk device according to one embodiment of the present invention. 1, reference numeral 1 denotes a file processing program, 2 denotes a logical record input / output unit, 3 denotes a physical record input / output unit, 4 denotes a virtual disk input / output unit, and 5 denotes a semiconductor storage device. Further, in the semiconductor storage device 5, 6 is a virtual disk, 7 is a track, 8 is a physical record storage area, 9 is a physical record, 10 is an access information storage area, and 11 is access information.

FIG. 2 is a flowchart of a program constituting the virtual disk input / output means 4. In the figure, 21 is a track address calculation step, 22 is an access information address calculation step, 24 is a physical record validity determination step, 25 is a physical record address calculation step, 26 is a physical record non-detection report step, and 27 is a physical record input / output. Step 28 is a normal end report step.

FIG. 3 is a diagram showing the contents of the access information. In the figure, 31 is a valid flag, 32 is a displacement within a track, and 33 is a physical record length.

Next, the operation of this embodiment having the above configuration will be described. The file processing program 1 activates the logical record input / output means 2 to perform logical record input / output. The logical record input / output means 2 obtains a physical record address in the storage device in which the requested logical record exists, and activates the physical record input / output means 3 to perform physical record input / output to the storage device. Virtual disk 6
In the case of the above file, the physical record address is a disk address including a cylinder number, a track number, and a physical record number. The physical record input / output means 3 activates the virtual disk input / output means 4 when the request is a physical record input / output request for the virtual disk 6.

The virtual disk input / output means 4 calculates the address in the semiconductor memory device 5 of the track 7 on which the physical record 9 exists from the cylinder number and the track number in the disk address of the physical record 9 (step 21). Based on the physical record number in the disk address 9, the address of the access information 11 in the semiconductor storage device 5 corresponding to the physical record 9 is calculated (step 22), and the access information 11 is input (step 23). The virtual disk input / output unit 4 determines whether the physical record 9 is valid or invalid based on the valid flag 31 in the input access information 11 (step 24). The fact that no record is detected is reported (step 26).

If it is valid, the address of the physical record 9 in the semiconductor storage device 5 is calculated from the address in the semiconductor storage device 5 of the track 7 where the physical record 9 exists and the displacement 32 in the track in the input access information 11. (Step 25), physical record length 33 in access information 11
Of the physical record 9 using the transfer length as the transfer length (step 27), and reports to the physical record input / output means 3 that the physical record input / output has been completed normally (step 2).
8). The physical record input / output means 3 reports to the logical record input / output means 2 that the physical record input / output has been completed normally, and the logical record input / output means 2 sends a logical record to the file processing program 1 in the case of input processing. Is returned, and in the case of output processing, reports that the logical record output has been completed normally.

[0013]

As described above, the present invention provides a virtual disk device having the following effects by obtaining the address of a required physical record in a semiconductor storage device based on access information. Can be. When inputting / outputting one physical record, access information may be input instead of inputting / outputting the entire track, so that the transfer amount is reduced and the processing time is shortened. Since the search is not performed in the track, the processing time is shortened. Since a buffer for reading access information may be used instead of a buffer for reading tracks, the amount of main storage can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a virtual disk device according to one embodiment of the present invention.

FIG. 2 is a flowchart of a program constituting virtual disk input / output means.

FIG. 3 is a diagram showing contents of access information.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 4 ... Virtual disk input / output means 5 ... Semiconductor storage device 6 ... Virtual disk 7 ... Track 9 ... Physical record 10 Access information storage area 11 ... Access information 31 ... Effective flag 32 ... Displacement in track 33 ... Physical record length

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06F 3/08

Claims (1)

(57) [Claims] (1) storing at least one physical record;
Physical record storage area to store and the physical record is valid
Validity flag indicating whether or not the
Intra-track displacement indicating relative displacement in the rack and the
Physical record length, which indicates the record length of the physical record.
Access information that stores access information for each physical record
A virtual disk containing tracks consisting of
And a semiconductor memory in which a logical record requested for input / output exists.
Storage device and physical record address in the semiconductor storage device
A logical record output means for obtaining the input and output request the input request is for the virtual disk
Physical record input / output means for determining whether or not the input / output request is an input / output request for the virtual disk
If it is, the syringe in the physical record address
The physical record exists from the data number and track number.
Calculate the address of the track in the semiconductor memory device, and
Of the track where the physical record exists in the semiconductor storage device
Address and the physical number in the physical record address.
Semiconductor storage device for access information corresponding to physical record
Address in the physical record
Access information and enter the corresponding physical record
The validity flag included in the access information is valid
Sometimes the semi-conductor of the track on which the physical record resides
Address in the physical storage device and the address corresponding to the physical disk.
From the in-track displacement included in the access information.
Calculate the address of the record in the semiconductor storage device,
The physical information included in the access information corresponding to the physical record.
Input / output of the physical record with record length as transfer length
And the result of inputting / outputting the physical record
Virtual disk input / output to notify physical record input / output means
And a physical disk input / output unit , wherein the physical record input / output unit inputs the physical record.
Receive notification of the output result and
Pass the result of input / output
The logical record input / output means inputs the physical record.
Receive notification of the output result and
If the input / output request source is an input request, the logical record
And return the result in the case of an output request.
A virtual disk device characterized by the following.