JPS60254440A - File device - Google Patents

Abstract

PURPOSE:To prevent destruction of files caused by contravention to the agreement between software and hardware, by detecting coincidence between the logical number of a unit recording area outputted in accordance with the starting command of a host device and a recognized logical number. CONSTITUTION:A control device 20b decodes the starting command SIO of a host device 10 and outputs an operation command signal to a device 20a. Moreover, the device 20a outputs an operation ending signal at the moment when the device 20a completes the process commanded by the operation command signal and the control device 20b, upon receiving the operation ending signal, returns a termination answering signal against the command SIO to the host device 10. When an error occurs in record number acting as a LOCATE command accompanying to the starting command SIO due to an erroneous command from software, namely, from the host device 10, no coincidence is obtained at a coincidence dicesion section 25 and a signal for reporting abnormality is outputted from the section 25, and then, no processing is performed thereafter.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a file device having a data recording medium such as a time tape, and particularly to a file device that can reliably protect data recorded on the recording medium. The present invention relates to a file device having such a structure.

[Background of the technology] As a file device having a data recording medium, for example, there is a magnetic disk device that uses a magnetic disk as the recording medium. Because the disk moves, the device cannot recognize in advance the location of the unit recording area, that is, the record that is actually being written or read, and always detects the home address or locates the location near the record. The target record is searched by recognizing the center value indicating the position. In response to this, in recent years, file devices such as CLS (Cartridge Library System) have been proposed in which a magnetic tape is used as a recording medium and a magnetic head moves relative to the magnetic tape to write or read data. However, the format on the magnetic tape in this case is as shown in FIG. 1, for example. This is because stripes S, which are a plurality of unit recording areas, are set on a magnetic tape. For example, eight stripes S constitute a block which is a unit partition, and the stripes S in the same block have a logical record number of 110. I
I to 117 II are respectively assigned. Then, when the first stripe (logical record number "0") of a predetermined block is located, the higher-level device performs the processing to be processed within the range that can be processed continuously.
That is, the stripe to be written or read is assigned logical record number 11 Q 11. l 111. "2",・
. . . Therefore, the file device side can always recognize in advance the position of the stripe to be written or read. That is, for example, stripe '0'.

Since it is predetermined that the next step after the processing for stripe "1" will be processing for stripe "1", when the device finishes writing to stripe "O'',
It can be recognized in advance that next writing or reading will be performed on stripe "1".

On the other hand, in the various file devices mentioned above, file supplementation is an important issue, and various measures are taken to prevent double writing to the same record and deletion of necessary data. There is.

[Prior Art and Problems] In conventional file devices, such as magnetic disk devices, countermeasures for capturing the file include checking the continuity of record numbers, and checking the physical record of the record corresponding to the specified record number. By checking the position, double writing of data and erasing of data in records other than the specified record are prevented.

However, all of the above-mentioned countermeasures involve adding files on the hardware, that is, checking to see if there are any errors in the operation of the device in response to commands from the higher-level device.
There has been a problem in that it is difficult to prevent file destruction due to violation of agreements between software such as commands from a host device and hardware on the device side.

On the other hand, even for file devices such as the CLS (Cartridge Library) mentioned above, the measures for supplementary file installation that have been considered in the past follow the same measures as the magnetic disk v device mentioned above. Defects are also reserved.

[Object of the Invention] The present invention has been made in view of the above, and has a plurality of unit recording areas on a data recording medium, and for each unit area composed of a predetermined number of unit recording areas. An agreement between software and hardware in a file device in which a logical number is assigned to a unit recording area included in a unit area, and the position of the unit recording area to be actually processed is recognized as a logical number within the unit area. The object of the present invention is to provide a file device that prevents file destruction due to violations as much as possible.

[Structure of the Invention] In order to achieve the above object, the present invention provides, in the file device, the logical number of the unit recording area outputted in response to a startup command from the host device and the recognized logical number. The device is equipped with a means for detecting a match, and is configured to execute processing based on the start command on the unit quantity edge area corresponding to the logical number output from the host device when the coincidence is detected by the means. be.

[Embodiments of the invention] Embodiments of the present invention will be described below based on the drawings.

FIG. 2 shows a system including a file device according to the present invention,
For example, it is a block diagram showing the basic configuration of CLS. In the figure, 10 is a host device, 20 is a file device, and this file device 20 is a device 20a that has a magnetic tape serving as a recording medium, a magnetic head for reading and writing, and other partial movement mechanisms. and device 20
and a control device 20b that performs control, etc.

Then, the control device 20b decodes the activation command SIO, which includes the Locate command and read/write commands that send information such as the record number from the host device 10, and
An operation command signal based on this activation command is output to the device 20a, and an operation end signal is output when the device 20a completes processing based on the operation command signal, and the operation end signal is inputted to the device 20a. The device 20b is designed to return a completion response signal to the above-mentioned command SIO to the host device 10.

Here, the configuration of the parts related to file supplementation in the control section 20b is as shown in FIG. 3, for example. Third
In the figure, 21 indicates Locate from the host device 10.
A transfer data storage section 22 stores the record number in the command, a logical record number storage section 22 stores the logical record number, and a logical record number storage section 23 stores the logical record number storage section 22 each time a read/write command is input from the host device 10. It is an octal addition unit that adds 1″ to the record number, and the logical record number storage unit 22 first stores the initial value II.
O11 is stored, and each time a read/write command is output from the host device 10, the logical record number incremented by 1'' is stored and held in the adder 23. That is, the control device 20b The position of the stripe to be actually processed is recognized in advance by the logical record number stored in the logical record number storage section 22.

Further, 24 is an AND processing unit that creates logical product information of the record number from the host device 10 and the logical record number in the logical record number storage unit 22, and 25 is an AND processing unit 2.
4 is a match determination unit that performs a match determination between the record number from the host device 10 and the logical record number in the logical record number storage unit 22 based on the logical product information from 4;
When the match determination unit 25 determines the match, it outputs a confirmation signal to the logical record number storage unit 22, and when the determination results in a mismatch, it outputs an abnormality reporting signal.

Next, the operation will be explained according to the flowchart shown in FIG. Here, the format on the magnetic tape is as shown in Figure 4 (same as Figure 1), and the startup command SIO
Assume that three read/write commands are chained, and three records are processed with one activation command.

First, based on a command from the host device 10, block n
The number m of blocks that can be processed continuously is determined, and this m value is stored in a register (not shown) (■, ■ in FIG. 5). and,
Stores the initial value 1101+ in the logical record number storage unit 22 and waits for the startup command SIO from the host device 10 (■,
). In such a state, when a startup command 8701 (see FIG. 4) is issued from the host device 10, a record number as a Locate command accompanying this startup command 8101 is stored in the logical record number storage unit 22. The match determination unit 25 determines whether there is a match with a certain logical record number “O” based on the output of the AND processing unit 24). A match is determined from Then, when a read/write command is executed for the stripe corresponding to the logical record number “O'° (■), the adder 23 activated by this read/write command adds the logical data in the logical record number storage unit 22. Record number "1" is added (■),
Thereafter, the record number 111jZ based on the read/write command chained in the startup command 8101
In the process of read/write processing for the stripe ~ corresponding to d12°', check whether a new start command SIO has been issued and whether the processing is for the stripe of the next block (■, ■). /Every time a write process is executed, "1'' is added to the logical record number in the logical record storage unit 22. Then, the read/write process for the stripe corresponding to record number "2" is completed. At this point, the logical record number storage section 2
The logical record number in 2 is 3'', and next time a new startup command 5I02 is issued from the host device 10, it is checked whether processing is to be performed on the stripe of the next block (■, 0 > Again, record number 11 as the Locate command accompanying this startup command 5IO2
3 II and the logical record number in the logical record number storage section 22 at this time + 13 II (■),
Thereafter, the same process as the process for startup command 5IO1 (■
.

■, ■, ■) are repeated.

Similarly, during the process of executing the process based on the startup command 5OI3, when the process for the stripe corresponding to record number +171+ is completed, the logical record number II 71 that has been stored in the logical record number storage unit 22 until now is
“1” will be added to 1, but the addition unit 23
By performing the increment processing, the new storage logical record number becomes "0".

Then, the next read/write process is performed on the next block (n+
1), furthermore, the next block (n+1
> can be processed, that is, whether block (n+1) is a block that can be processed consecutively from block n. In this case, since it can be processed, first register 1″ from the m value stored in (not shown)
After subtracting ((i3)), the same processing as above is performed.

Thereafter, for example, a startup command 5I04.5 as shown in FIG.
I05.5I06.5I07. - The same process as above is performed for GC.

Furthermore, if the record number as the locate command associated with the new startup command SIO corresponds to the first stripe of the block, check whether the block can be processed in the same way as explained in the processing based on the startup command 5IO3 above. Q), if processing is possible, a register that stores the number of blocks that can be processed continuously at the current time (not shown)
After subtracting "1" from the corresponding value (0), normal processing is performed.

In the process of the above-mentioned series of processes, for example, due to an error in the command from the software, that is, the host device 10, the activation command 8
If an error occurs in the record number as the Locate command associated with 10, the match determination unit 25 will not be able to find a match, and the match determination unit 25 will output an abnormality reporting signal (■) and no further processing will be performed. It will no longer be possible.

In addition, in the process of a series of processes based on the start command SIO, if the process extends to the next block, or when the start command SIO
When the record number as a Locate command associated with IO starts from the one corresponding to the first stripe of the block, it is checked whether the next block can be processed (■, ◎), but at this time, the next block Even if the number of blocks exceeds the range of blocks that can be processed continuously starting from block n, the control device 20b outputs an abnormality signal to the host device 10.

As described above, according to this embodiment, each time a startup command SIO is issued from the host device 10, the record number indicated by the initial Locate command accompanying the startup command 810 is recognized in the control device 2Ob. The software (host device 10 ) and hardware (control device 20
b) Files are completely protected against violations of the agreement regarding stripe processing order with

Furthermore, it becomes possible to protect the file across multiple activation command SOIs.

[Effects of the Invention 1] As explained above, according to the present invention, a data recording medium has a plurality of unit recording areas, and each unit section consisting of a predetermined number of unit recording areas, A logical number is assigned to the unit recording area included in the unit partition, and
In a file device that recognizes the location of the unit recording area to be actually processed as a logical number within the upper unit partition, the logical number of the unit recording area output in response to a startup command from the higher-level device and the above recognition. The system detects a match between the logical numbers that are being used, and executes processing based on the start command on the unit recording area that corresponds to the logical number output from the host device when this match is detected. File protection against violation of the agreement regarding the processing order of unit recording areas between software and hardware becomes complete, and a more reliable file device can be realized.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the format of a magnetic tape in a CLS (cartridge library system) that uses magnetic tape as a recording medium, and FIG. 2 is a block diagram showing the basic configuration of a system to which a file device according to the present invention is applied. , FIG. 3 is a block diagram showing an example of the configuration of the parts related to file protection of the control device in FIG. An explanatory diagram showing an example of the state, FIG. 5 is a flowchart showing the operation of the apparatus shown in FIG. 3. 10... Upper device 20... File device 20a.
...Device 21b...Control device 21...Transfer data storage section 22...Logical record number storage section 23...Calculation section 24...AND processing section 25...
Matching determination unit Fig. 1 Fig. 2 Fig. 0 Fig. 3 Fig. 4

Claims (1)

[Claims] For each unit section that has multiple unit recording areas on a data recording medium and is composed of a predetermined number of unit recording areas, a logical number is assigned to the unit recording area included in the unit section, and a logical number is assigned to the unit recording area included in the unit section. In a file device that recognizes the location of the unit recording area to be stored as a logical number within the unit partition, the above is recognized as the logical number of the unit recording area that is output in response to a startup command from the host device. A means for detecting a coincidence of logical numbers is provided, and when the coincidence is detected by the means, the process according to the start command is executed for the unit recording area corresponding to the logical number output from the host device. A file device characterized by: