JPH0320772B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Technical Field of the Invention The present invention relates to a virtual FBA pseudo processing device, particularly a virtual fixed block direct access device (FBA-
DASD) to a direct access device (CKD-DASD) with a normal count area,
Using a virtual computer system, input/output instructions to fixed block direct access devices can be sent to CKD-
Virtual simulation and execution using DASD
This relates to an FBA pseudo processing device.

(B) Prior art and problems Conventionally, when developing and supporting new input/output devices, operating systems (CS),
For independent utilities that are loaded and executed independently of the OS, debugging of the support software should be started after the input/output device hardware is provided to the software development department, or A simulator was created for each utility and used to continue debugging until an actual input/output device was provided. As a result, there were problems such as delays in software debugging, the large number of man-hours required to create each simulator, and the high risk of bugs occurring in the simulators, making them ineffective.

By the way, recently, virtual computer systems have been widely used in which a virtual computer environment is prepared so that various OSs can operate as if they were occupying real hardware.
It is believed that by using this virtual computer system, it is possible to debug software related to non-existent devices relatively efficiently. However, conventionally, when simulating virtual machine input/output commands, etc., the application is limited to cases where the input/output device is of the same type, that is, when the channel command system is common, and when the channel command system is different, could not be applied. In particular, new magnetic disk devices in which the data area for storing data is made into a fixed block have a conventional count C area, key K area, and data D area, so-called
The channel command system is completely different from that of a CKD magnetic disk drive, and in the absence of hardware, it is not easy to simulate input/output commands and create a software debugging environment.

(C) Object and Structure of the Invention The present invention aims to solve the above-mentioned problems, and utilizes a virtual machine to actually perform READ/WRITE operations of an OS or an independent utility on a fixed block direct access device (FBA-DASD).
The aim is to be able to run it even if DASD does not exist, just as if it were present. Therefore, the virtual FBA pseudo processing device of the present invention includes a virtual computer that acquires virtually assumed hardware resources and performs execution processing, a virtual computer control unit that manages and controls the virtual computer, and a virtual computer that controls the size of each data area. at least a direct access device having a storage area having a count area defining the count area;
The direct access device is formatted in advance so that each data area has a predetermined size, and the virtual computer control unit creates a virtual fixed block direct access device in which each data area is made into a fixed block for the direct access device. an input/output instruction simulator that simulates virtual input/output instructions issued by the virtual machine and recognizes input/output requests to the fixed block direct access device; and an input/output instruction simulator that checks the CCW for the fixed block direct access device. It is equipped with a CCW conversion unit that converts the CCW to a CCW for a direct access device having a count area as described above, and executes input/output for an input/output operation to a virtual fixed block direct access device under an actual direct access device having a count area. It is characterized by the fact that it is made to do so. This will be explained below with reference to the drawings.

(D) Embodiment of the Invention Fig. 1 shows the configuration of an embodiment of the invention, Fig. 2 is an explanatory diagram of the storage area of a direct access device related to the invention, and Fig. 3 is a diagram for explaining an example of CCW conversion. Show the diagram.

In the figure, 1 is the format part, 2 is the actual CKD-
DASD, 3 is a virtual FBA-DASD, 4 is a virtual console, 5 is a virtual machine control unit (CP), 6-1 to 6-n are virtual machines (VM), 7 is an operating system, 8 is an SIO instruction, 9 is an interrupt reception unit, 10 is a program check handler, 11 is an input/output instruction simulation unit, 12 is an analysis unit, 13 is an FBA recognition unit, 14 is a CCW conversion unit,
15 is an error check section, 16 is a conversion table, 17 is an actual input/output command issuing section, 18 is a device correspondence instruction section, 19 is an actual input/output interrupt handler, 20 is an interrupt notifying section, and 21 is a termination determining section.

The actual CKD-DASD 2 is, for example, a conventionally existing magnetic disk device, and the storage area in the track includes a count area C, a key area K, and a data area for each record, as shown in FIG. D
It has The position information of the record, the size of the key area and the size of the data area of the record are written into the count area C at the stage of formatting. The formatting unit 1 is an independent utility that formats the real CKD-DASD 2, and in the case of the present invention, it is activated only once at the beginning, and is used to format the virtual CKD-DASD 2.
Each data area D is formatted to the block length of the data area of the FBA-DASD 3, for example, 512 bytes.

Virtual FBA (Fixed Block Architecture) −
The DASD 3 is a new magnetic disk device in which each data area 30, 30, . . . has a fixed size of 512 bytes, as shown in FIG. A count area C such as
This is an area that does not have a key area K or a key area K. Therefore, a physical block number is used for the address of the storage area to be accessed, and its channel command system is completely different from that of the real CKD-DASD2. The virtual FBA-DASD 3 does not exist in this embodiment, but as described later, the OS 7 uses the virtual FBA-DASD3.
- It can be processed as if DASD3 exists.

The virtual console 4 is a console conventionally known in virtual computer systems, and is
7 or CP5. The CP5 is a control unit that controls the virtual machine, manages the memory mapping table, issues instructions regarding input/output to the real input/output device, processes various interrupts, etc. The virtual machines 6-1 to 6-n are devices to which virtual hardware resources are allocated by the CP5.
The OS 7 controls various application processing units that operate under it, and performs control to perform data processing required by the user. OS7 is virtual machine 6-1
Executes processing as one independent computer.

Program check handler 10 is an OS
This is to detect a program interrupt caused by an instruction issued by No.7. Under virtual machine 6-1,
Since OS7 runs in the so-called problem mode, for example, if you issue SIO instruction 8, a program check will occur due to the prohibition of the use of privileged instructions, and the program check handler 1 of CP5 will be executed.
Control is now shifted to 0. The input/output command simulator 11 simulates a virtual SIO command issued by the OS 7 into an SIO command for a real device. The analysis unit 12 is a virtual
Analyzing the contents of the SIO command, the FBA recognition unit 13
This is to identify whether the analyzed SIO instruction is for virtual FBA-DASD.

The CCW conversion unit 14 obtains control from the FBA recognition unit 13 and converts the channel command word (CCW) for the virtual FBA-DASD 3 into the real CKD-DASD.
This is to convert to CCW for DASD2.
The error check unit 15 checks errors in access range, command format, etc. when converting CCW, and checks the actual FBA-DASD.
When new hardware is developed, the same checks are performed on that hardware. The conversion table 16 converts the real CKD-DASD2 and the virtual FBA-DASD for CCW conversion.
It holds information on the correspondence relationship between CCW and DASD3. The actual input/output command transmitting unit 17
Sends an SIO command to CKD-DASD2.

The device correspondence instruction unit 18 allocates the real CKD-DASD 2 as the real device of the virtual FBA-DASD 3 by inputting a command from the virtual console 4 . The actual input/output interrupt handler 19
Control is obtained by input/output interrupts from CKD-DASD2. The interrupt notifying unit 20 notifies the interrupt accepting unit 9 of the OS 7 of an interrupt caused by the execution of an input/output command. however,
In the case of this embodiment, when converting a CCW by the CCW converter 14, a series of CCWs is divided into a plurality of parts,
Since SIO commands may be sent,
The termination determination section 21 checks whether all CCWs are terminated. If the CCW has not been completed yet, the CCW conversion unit 14 is notified and processing for the remaining CCW is continued.

Next, the processing operation of the embodiment shown in FIG. 1 will be explained. The real CKD-DASD 2, which is used as a substitute for the virtual FBA-DASD 3, is formatted in advance by the format unit 1 so that each data size is the same as the virtual FBA-DASD.
Formatted to match DASD3 fixed block size. Virtual FBA-DASD
3 and the real CKD-DASD 2, for example, the SFBA input from the virtual console 4
(SetFBA) command. The command is transmitted to the device compatibility instruction section 18, and the device compatibility instruction section 18 transmits the compatibility information to the FBA recognition section 13,
It is reflected in the conversion table 16 and the like. As a result, the access environment for the virtual FBA-DASD 3 is prepared, and from now on, the OS 7 can execute processing as if the virtual FBA-DASD 3 actually exists.

When the OS 7 prepares the CCW for the virtual FBA-DASD 3 and issues the SIO instruction 8, control is transferred to the program check handler 10 due to the program check. When the program check handler 10 determines that the cause of the program check is the issuance of an SIO instruction, it activates the input/output instruction simulator 11. The input/output command simulator 11 uses the analyzer 12 to analyze the SIO command from the virtual machine 6-1, and then uses the FBA recognizer 13 to analyze the SIO command from the virtual machine 6-1.
Determine whether it is for FBA-DASD3. If the SIO instruction is for the virtual FBA-DASD 3, the CCW conversion unit 14 is called.

The CCW converting section 14 first refers to the channel address word CAW of the virtual machine 6-1 using the error checking section 15, and checks whether the CAW and CCW are normal. If there is an error, the condition code or interrupt is simulated.
Notify the SIO source OS7. If there is no error, the conversion table 16 is referred to and CCW conversion is performed.

Channel commands for the virtual FBA-DASD 3 include, for example, those shown in FIG.
The DEFINEEXTENT command 31-1 specifies the range to be accessed. The LOCATE command 31-2 locates the head in the fixed block to be accessed. The READ command 31-3 instructs to read fixed block data, and the WRITE command 31-4 instructs to write data.
The CCW conversion unit 14 converts the command as shown in FIG. 3A into a real CKD-DASD 2 as shown in FIG.
channel command 32, but the actual
The channel command 32 of the CKD-DASD 2 is well known, so detailed explanation will be omitted. Note that the position of the data area on the virtual FBA-DASD 3 is represented by a physical block number, so it must be converted into a so-called CCHHR consisting of a cylinder number, head number, and record number indicating the position in the real CKD-DASD 2. will be held. The record number R is determined, for example, by the remainder obtained by dividing the physical block number by the number of records in one track. The head number HH is determined by the remainder of the quotient of the above calculation result divided by the number of heads, and the cylinder number CC
is determined by its quotient. .

After creating a CCW group corresponding to the CCW of the actual CKD-DASD2, input/output instruction simulator 11
The actual input/output command transmitting unit 17 transmits the actual SIO command via. By this, the actual CKD
- Input/output operations to the DASD 2 are performed, and at the end of the operation, for example, a channel end or device end interrupt occurs. The actual input/output interrupt handler 19 obtains control by this interrupt and starts the interrupt notification section 20. The interrupt notification unit 20 is
It is determined whether the input/output interrupt is related to the virtual FBA-DASD 3, and if so, the termination determination unit 21 is notified. The termination determination unit 21 determines whether execution of all virtual input/outputs has been completed based on the type of interrupt, and if not all have been completed, the CCW conversion unit 14 again converts the remaining CCWs. Create it and control the request to send the actual SIO command. When the execution of all virtual input/outputs is finished, the interrupt notification unit 2
0, and the interrupt notifying unit 20 notifies the interrupt receiving unit 9 of the OS 7 of completion of input/output to the virtual FBA-DASD 3. As a result of the above, the OS 7 can process the virtual FBA-DASD 3 as if it actually existed.

The same applies to the case where a so-called SIOF instruction is used instead of the SIO instruction in the above embodiment. Similarly, if an independent utility runs on a virtual machine instead of the OS, the virtual FBA
DASD can be simulated with real CKD-DASD.

(E) Effects of the invention As explained above, according to the present invention, FBA-
Input/output to DASD is actually performed between FBA and DASD.
Even if a system does not exist, it can be simulated using existing equipment, making it possible to debug software such as the OS or independent utilities in advance of providing the hardware. In particular, since it is absorbed by the virtual computer control unit (CP) in the virtual computer system, it has great versatility. Furthermore, it can be used not only for debugging purposes, but also for program compatibility, such as running a newly developed program for FBA-DASD on an existing system that does not have FBA-DASD. Also,
By implementing it on a virtual computer system, it is possible to consistently test or operate multiple OS or independent utilities from the initial setting (IPL) stage to completion. Furthermore, since it is possible to use functions already provided by the virtual computer system, such as I/O and CCW trace functions, it is possible to debug the OS efficiently and easily.

[Brief explanation of the drawing]

FIG. 1 shows the configuration of an embodiment of the present invention, FIG. 2 is a diagram illustrating a storage area of a direct access device related to the present invention, and FIG. 3 is a diagram illustrating an example of CCW conversion. In the diagram, 2 is real CKD-DASD, 3 is virtual FBA-
DASD, 5 is a virtual computer control unit, 6-1 to 6
-n represents a virtual computer, 11 represents an input/output instruction simulating section, 14 represents a CCW converting section, and 18 represents a device correspondence instruction section.

Claims (1)

[Claims] 1 A virtual computer that obtains and executes virtually assumed hardware resources, a virtual computer control unit that manages and controls the virtual computer, and a storage area that has a count area that defines the size of each data area. The direct access device is formatted in advance so that each data area has a predetermined size, and the virtual machine control unit formats each data area into a fixed block for the direct access device. an input/output command simulator that simulates virtual input/output commands issued by the virtual machine and recognizes input/output requests to the fixed block direct access device; For the above fixed block direct access device
It is equipped with a CCW conversion unit that checks the CCW and converts it into a CCW for a direct access device having the above-mentioned count area. A virtual machine characterized by the fact that it executes output.
FBA pseudo processing device.