JPH0512170A - Input/output control system - Google Patents

Abstract

PURPOSE:To attain a double writing operation to a disk, etc., with a single input/output operation by providing a means which makes an input/output controller and a peripheral controller carry out the same channel program at one time via a CPU and then controls the different input/output devices. CONSTITUTION:The input/output devices 105 and 106 are connected to a CPU 100 via the device interfaces 111 and 112, and the peripheral controllers 103 and 104 respectively. The software of the CPU 100 is provided with a channel program header and a channel program and starts the input/output controllers 101 and 102 with the physical channel designation 510. In this case, a PCU O 512 and a PCU 1 514 contained in the designation 510 are required to designate the absolute numbers of the controllers 103 and 104 connected to the due controllers 101 and 102 respectively. Thus the controllers 101 and 102, and the controllers 103 and 104 can control the devices 105 and 106 respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an input / output control system, and more particularly to
The present invention relates to an input / output control method for controlling an input / output device by a plurality of hardware.

[0002]

2. Description of the Related Art Conventionally, this type of input / output control system is shown in FIG.
As shown in FIG. 5, the central processing unit 300 was connected to the input / output device 305 via one input / output control device 301 and one peripheral control device 303. Alternatively, as shown in FIG. 7, the input / output device 205 is cross-call connected to the central processing unit 200 via the interfaces 211 and 212 via the two peripheral control devices 203 and 204.

In the conventional system, one channel program is activated for a single path for input / output operation. That is, one input / output control device interprets and executes a channel program for one input / output operation.

[0004]

In the above-mentioned conventional input / output control system, only one input / output control device operates for one channel program, so (1) the same data is written in different disks. In order to realize the "double writing" of the above, the software has a drawback that it is necessary to start the channel program for two different disks twice.

(2) From the central processing unit to the input / output control unit,
Through the peripheral control device, on the route to the input / output device,
There is a drawback in that there is a slight anxiety that intermittent data garbling occurs and that the data garbling may not be detected by the error check 7 mechanism. (Data integrity is uncertain) (3) If the I / O operation ends abnormally due to an error in the I / O control unit or peripheral control unit, it is necessary to restart the I / O operation. However, there is a drawback in that software overhead is required.

[0006]

An input / output control system according to a first aspect of the present invention is a central processing unit, a plurality of input / output control units from the central processing unit through separate interfaces, and further separate from the input / output control unit. In the input / output control system including a plurality of peripheral control units through the I / O interface, and an input / output unit connected from the peripheral control unit to the central processing unit by different device interfaces, the same central processing unit is used. The above channel program is simultaneously executed by different input / output control devices and peripheral control devices to control different input / output devices.

In the input / output control system of the second invention, means for controlling the same input / output device by causing the central processing unit to simultaneously execute the same channel program in different input / output control devices and peripheral control devices. The input / output device compares the first-arriving output data with the later-arriving output data and performs an actual output operation only when they match.

In the input / output control system of the third invention, means for controlling the same input / output device by causing the central processing unit to simultaneously execute the same channel program in different input / output control devices and peripheral control devices. The input / output device performs an actual output operation based on the first-arriving output data and ignores the second-arriving output data.

According to a fourth aspect of the present invention, there is provided an input / output control system for controlling different input / output devices by causing the central processing unit to simultaneously execute the same channel program in different input / output control devices and peripheral control devices. Means for writing first-arriving input data to the main memory by the input / output control device, and transfer of the input data to the central processing unit via the other peripheral control device and the input / output control device, and the already-written input data And means for performing at least one comparison with the input data.

In the input / output control system of the fifth invention, means for controlling the same input / output device by causing the central processing unit to simultaneously execute the same channel program in different input / output control devices and peripheral control devices. Means for writing first-arriving input data to the main memory by the input / output control device, and transfer of the input data to the central processing unit via the other peripheral control device and the input / output control device, and the already-written input data It is provided with a means for comparing and collating the input data at least once.

According to a sixth aspect of the invention, there is provided means for controlling the same input / output device by causing the central processing unit to simultaneously execute the same channel program in different input / output control devices and peripheral control devices. A means for writing the input data which the input / output control device has arrived first to the main storage device, and an error in the process of transferring the input data to the central processing unit via the other peripheral control device and the input / output control device. And means for terminating the input / output operation normally when detected.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of an embodiment of the present invention. The input / output devices 105 and 106 are device interfaces 11
1, 112 are connected to the central processing unit 100 via peripheral control devices 103, 104.

FIG. 2 is a diagram showing the structure of a channel program. One input / output operation is defined by the channel program header 400 and the channel program 401. The channel program header-400 includes a "physical channel designation" for designating a physical resource that actually performs an input / output operation. This will be described later.
The channel program 401 is formed by a plurality of commands, and each command becomes a unit of input / output operation performed by the input / output control device and the peripheral control device.

FIGS. 3A and 3B are diagrams showing an example of the format of physical channel designation. In the conventional method, the old physical channel designation 500 was used. The old physical channel designation has a 1-byte length, and the upper 4 bits are I.
UN501, the absolute number of the input / output control unit on which the channel program is to be executed, and the lower 4 bits are PCU502, which indicates the absolute number of the peripheral control unit on which the channel program is to be executed. That is, one input / output path is determined by designating the old physical channel, and one input / output control device to execute the channel program is determined.

The physical channel designation 510 is an extension of the old physical channel designation 500. With this format, two input / output control devices can be activated at the same time. Bits 0 and 8 of the physical channel designation 510 have the function of validating the same bits 1 to 7 and the same bits 9 to 15, which are called V0515 and V1 516, respectively. That is, when V0 515 is "1", it is the same. Bit 1
7 to 7 are valid, and the input / output control device designated by the same bits 1 to 3; IUN0 is activated. When V1516 is "1", the same bits 9 to 15 are valid and the same bit 9
-11: The input / output control device designated by IUN1 is activated.

The operation of the first invention will be described. Figure 1
In the system configuration shown in FIG. 3, the software of the central processing unit 413 in FIG. 2 prepares the channel program header 400 and the channel program 401, and
The input / output control devices 411 and 412 are activated using the physical channel designation 510 in (a). At this time, both V0 515 and V1 516 in the physical channel designation 510 are "1". Also IUN0 51
1 and IUN1 513 are input / output control devices 411, respectively.
And the absolute number of the input / output control device 412.
Similarly, PCU0512 and PCU1514 need to specify the absolute numbers of the peripheral control units to which the target input / output devices are connected.

The value of the physical channel designation 510 in the example of FIG. 1 is (91A) ₁₆ . In this case, the input / output control devices 101 and 102 and the peripheral control devices 103 and 10 in FIG.
4 can control the input / output devices 105 and 106.

The second invention will be described. FIG. 4 is a block diagram of the input / output device 600 showing the details of the input / output device 205 of FIG. The buffers 611 and 612 are for storing the output data sent from the device interfaces 601 and 602, respectively. The multi-selector 613 is for switching the output data in the buffer 611 to the device or the comparator 614. The comparator 614 is for comparing the output data in the buffers 611 and 612. In the system configuration shown in FIG. 7, as described above, the same channel program is used for the two input / output control devices 201 and 202 and the two peripheral control devices 2.
03, 204 will be executed. One difference from the above example is that the peripheral control devices 203 and 204 are connected to the same input / output device 205.

The operation of the input / output device 205 will be described below with reference to FIG.
Use to explain. Here, consider the operation when the peripheral control device performs writing to the device, that is, output data transfer. The output data sent from the device interfaces 601 and 602 are temporarily stored in the buffers 611 and 612. The sizes of the buffers 611 and 612 need to be large enough to store the entire output data once. The output data may be stored in the buffer 611 or 612 in either order.

When both output data are complete, the buffer 611 and the buffer 6 are passed through the multiplexer 613.
The 12 output data are compared by the comparator 614. Only when the results match, the output data of the buffer 611 is actually sent to the device through the multiplexer 613, and the actual output operation (for example, writing to the disk) is performed.

The third invention will be described with reference to FIG. In the system configuration shown in FIG. 7, the same channel program is simultaneously executed by the input / output control devices 201 and 202 and the peripheral control devices 203 and 204 to control the same input / output device 205. Here, the peripheral control devices 203, 2
Consider the operation when 04 performs output data transfer. The input / output device 205 performs an actual output operation based on the output data that arrives first. The output data that arrives later is stored in the buffer 61 of FIG.
1, 612 and ignored.

The fourth invention will be described with reference to FIG. FIG. 5 is a block diagram showing details of the central processing unit 100 shown in FIG.

Data from the input / output control devices 101 and 102 are distributed to the main memory device 710 and the comparator 711 via the multiplexers 712 and 713, respectively. The main storage device 710 is for writing the first-arrival input data of the input data from the two input / output control devices. The comparator 711 is for comparing the input data in the main storage device 710 with the input data that arrives after being transferred via the interface 701 or 702. Flags 714 and 715 are flags for controlling first-arrival / last-arrival of input data. The flags 714 and 715 have an initial state of “0” before the input / output is activated,
It is set to "1" upon receipt of the first byte of input data from 01 or 702.

Two input / output devices 1 are caused by the input / output control devices 101 and 102 to simultaneously execute the same channel program.
05 and 106 are controlled. Hereinafter, the input / output control device 10
Consider the operation when 1, 102 perform reading from the device, that is, input data transfer. It is assumed here that, of the interfaces 701 and 702, the input data sent via the interface 701 arrives first at the central processing unit 700. Input data from the interface 701 is written in the main memory 710 through the multiplexer 712 after it is confirmed that the flag 715 is "0". Flag 714 is set to "1" when it receives the first byte of input data.

Next, when the central processing unit 700 receives the input data from the interface 702, the flag 71
Check 4. Since the value is “1”, the input data is sent to the comparator 711 through the multiplexer 713.
Sent to. Further, the input data already written in the main memory device 710 is input as another input to the comparator 711, and the sequential input data is collated. If all the information of the input data is received and the collation results match, the input / output processing at that time is processed as normally completed.

The fifth invention will be described with reference to FIG. The same channel program is simultaneously executed by the input / output control devices 201 and 202 and the peripheral control devices 203 and 204 to control the same input / output device 205. Here, consider the operation when the input / output control devices 201 and 202 transfer input data. Regarding the operation of the input / output device 205,
The input data from the interfaces 701 and 702 are collated, and when they are in agreement, the input / output processing is processed as normally completed.

The sixth invention will be described with reference to FIG. The same channel program is simultaneously executed by the input / output control devices 201 and 202 and the peripheral control devices 203 and 204 to control the same input / output device 205. Here, consider the operation when the input / output control devices 201 and 202 transfer input data. The central processing unit 200 writes the first-arrival input data in the main storage device 710. The late-arriving input data is ignored and discarded by the central processing unit 200. At this time, the first-arrival / last-arrival control is performed by flags 714 and 715.
Controlled by.

[0028]

According to the first aspect of the present invention, the same channel program is executed by a plurality of input / output control devices and peripheral control devices so that a plurality of input / output devices simultaneously perform the same output operation. Therefore, it is possible to double-write on a disk or the like by starting the I / O once, without the software performing the I / O plural times.

(2) According to a second aspect of the present invention, the same channel program is executed by a plurality of input / output control devices and peripheral control devices, and the output data that arrives first and the one that arrives later are combined in one input / output device. By performing the actual output operation only when the results of comparison and comparison are the same, it is possible to prevent data errors that may occur in the path from the central processing unit to the input / output device, and output operation with high data integrity. Is effective.

(3) In the third invention, the same channel program is executed by a plurality of input / output control devices and peripheral control devices to control the same input / output device. Since the input / output device performs the actual output operation based on the first-arriving output data, it is sufficient that the output data reaches the input / output device from one of the plurality of paths, so that it is possible to realize the input / output control with high possibility. is there.

(4) In the fourth invention, the same channel program is executed by a plurality of input / output control devices and peripheral control devices to control the plurality of input / output devices. The central processing unit is
Occurs on the path from the input / output device to the central processing unit by writing the first-arrival input data to the main memory and comparing the latter-arrival input data with the former and terminating the I / O operation normally only when they match. It is possible to prevent possible data errors, and it is possible to perform an input operation with high data integrity.

(5) In the fifth invention, the same channel program is executed by a plurality of input / output control devices and peripheral control devices to control one input / output device. The central processing unit is
Occurs on the path from the input / output device to the central processing unit by writing the first-arrival input data to the main memory and comparing the latter-arrival input data with the former and terminating the I / O operation normally only when they match. It is possible to prevent possible data errors, and it is possible to perform an input operation with high data integrity.

(6) In the sixth invention, the same channel program is executed by a plurality of input / output control devices and peripheral control devices to control the same input / output device. Since the central processing unit writes to the main storage unit based on the first-arriving input data, it is only necessary for the input data to reach the central processing unit from one of a plurality of paths, so that the input / output control with high possibility can be realized. There is an effect.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a channel program.

3 (a) and 3 (b) are diagrams showing a format for specifying a physical channel.

FIG. 4 is a block diagram showing details of an input / output device.

FIG. 5 is a block diagram showing details of a central processing unit.

FIG. 6 is a block diagram showing a first conventional example.

FIG. 7 is a block diagram showing a second conventional example.

[Explanation of symbols]

100, 200, 300, 413, 700 Central processing units 101, 102, 201, 202, 301, 411, 4
12 I / O control devices 103, 104, 203, 204, 303 Peripheral control devices 105, 106, 205, 305, 600 I / O devices 107, 108, 207, 208, 307, 701, 7
02 interfaces 109, 110, 209, 210, 309 input / output interfaces 111, 112, 211, 212, 311, 601 and 6
02 device interface 400 channel program header 401 channel program 500 old physical channel designation 510 physical channel designation 501 IUN1 502 PCU 511 IUN0 512 PCU0 513 IUN1 514 PCU1 515 V0 516 V1 611,612 buffer 613,712,713 multiplexer 614,711 710 main memory 714, 715 flag

Claims (6)

[Claims] 1. A central processing unit, and a plurality of input / output control units from the central processing unit through separate interfaces,
An input / output control system further comprising a plurality of peripheral control devices from the input / output control device through separate input / output interfaces, and an input / output device connected from the peripheral control device to the central processing unit through separate device interfaces 2. An input / output control system according to claim 1, further comprising means for causing the central processing unit to simultaneously execute the same channel program in different input / output control devices and peripheral control devices to control different input / output devices. 2. Means for controlling the same input / output device by causing the input / output control device and the peripheral control device to simultaneously execute the same channel program by the central processing unit, and the output which the input / output device has arrived first 2. The input / output control system according to claim 1, further comprising means for comparing the data with the output data that comes later and performing an actual output operation only when they match. 3. A means for controlling the same input / output device by causing the central processing unit to simultaneously execute the same channel program to the different input / output control device and the peripheral control device, and the output which the input / output device has arrived first. The input / output control system according to claim 1, further comprising means for performing an actual output operation based on the data and ignoring the output data that arrives later. 4. A means for causing the central processing unit to simultaneously execute the same channel program in different input / output control devices and peripheral control devices to control different input / output devices, and the input / output control device is first arrived. A means for writing the input data to the main memory, and a means for transferring the input data to the central processing unit via the other peripheral control device and the input / output control device and comparing and collating the input data already written. The input / output control system according to claim 1, further comprising means for performing at least once. 5. The means for controlling the same input / output device by causing the central processing unit to simultaneously execute the same channel program to the different input / output control device and the peripheral control device, and the input / output control device comes first-come-first-served basis. A means for writing the input data to the main memory, and a means for transferring the input data to the central processing unit via the other peripheral control device and the input / output control device and comparing and collating the input data already written. The input / output control system according to claim 1, further comprising means for performing at least once. 6. A means for controlling the same input / output device by causing the central processing unit to simultaneously execute the same channel program to the different input / output control device and the peripheral control device, and the input / output control device arrives first. A means for writing the input data to the main memory and a normal input / output operation when an abnormality is detected in the process of transferring the input data to the central processing unit through the other peripheral control device and the input / output control device. The input / output control system according to claim 1, further comprising: