JPH08255120A - I / O controller - Google Patents

Abstract

(57) [Abstract] [Purpose] An I / O controller for an I / O device that can accept the next command while the I / O device is executing is intended to enable efficient command issuing. An I / O controller includes an I / O controller and a channel controller that controls a channel connecting the I / O device. The I / O controller regards the I / O device as a plurality of virtual devices and It has a configuration to issue a command to.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an input / output control device for an input / output device. In particular, it relates to an I / O controller that can issue the next command to the I / O device without waiting for the completion report of the command in the I / O device.

[0002]

2. Description of the Related Art A conventional input / output device such as a magnetic disk device cannot receive the next command during command processing, and after the command processing ends, the input / output control device ends the command. To receive the next command issued by the I / O controller. For this reason, the magnetic disk device does not do anything and wastes time until the next command is received after the command processing is completed.

FIG. 12 is a diagram showing the configuration of a conventional magnetic disk device and an input / output control device. In FIG. 12, 31
Reference numeral 0 is an input / output control device.

Reference numeral 315 is an input / output control unit, which is a magnetic disk device A (340) and a magnetic disk device B (345).
I / O control is performed. A command issuing unit 320 receives a command issued from a device (not shown) on the application program side and issues a command to the channel control unit 330.

The command issuing unit 320 issues a command after confirming that the magnetic disk device A (340) or the magnetic disk device B (345) to which the command is issued is not in execution.

A command receiving unit 322 receives a command from the channel control unit 330. Three
Reference numeral 30 denotes a channel control unit, which is a magnetic disk device A
(340), the channel control for the magnetic disk device B (345) is performed.

A channel processor 331 for the magnetic disk unit A controls the channel of the magnetic disk unit A (340). Reference numeral 332 is a channel processing unit for the magnetic disk device B.
The channel control of (345) is performed.

Reference numeral 340 is a magnetic disk device A. 34
Reference numeral 5 is a magnetic disk device B. The operation of the configuration of FIG. 12 will be described.

When the input / output control unit 315 needs to issue a command (for example, when a command is input from a device on the application program side or a command is issued from the magnetic disk device side, a command responding thereto is issued. Etc.), magnetic disk unit A (34
0) or a command is issued to the magnetic disk device B (345). Hereinafter, the case of issuing a command to the magnetic disk device A (340) will be described.

When the command issuing unit 320 receives a command from the device on the application program side, it issues the command to the magnetic disk device A (340), and the channel processing unit 331 of the magnetic disk device A causes the magnetic disk device A (340). ) To the command.

A command issued from the magnetic disk device A (340) such as a process end command issued in the magnetic disk device A (340) when the command processing is completed is input / output via the channel controller 330. The command receiving unit 322 of the control unit 315 receives the command, and the command issuing unit 320 issues a response command of the command to the channel control unit (330) or the device on the application program side, or performs termination processing.

[0012]

The conventional magnetic disk device cannot accept the next command during command processing, and the input / output control device issues a command issued from the magnetic disk device, such as command processing end command. After receiving it, I issued the following command.

Therefore, in the conventional magnetic disk device, it takes a long time to issue a command to the input / output control device and wait for the next command input in response to the command, and no processing is performed during that time. It was time.

Therefore, a magnetic disk device has been developed which receives the next command and processes the command efficiently even while the command is being processed. However, the present invention is an input / output device that can efficiently issue a command in such a magnetic disk device. An object is to provide a control device.

[0015]

According to the present invention, in an input / output control device capable of accepting a command even during command processing, the input / output control device is provided with a channel for connecting the input / output control unit and the input / output device. A channel control unit for controlling is provided, and the I / O control unit considers the I / O device as a plurality of virtual devices and issues a command to the virtual devices, so that the device on the application program side normally operates. You can now issue commands as you would for any I / O device.

FIG. 1 shows a basic configuration (1) of the present invention (corresponding to claims 1, 2 and 3). In FIG. 1, reference numeral 1 is an input / output control device.

Reference numeral 5 is an input / output control unit. A command issuing unit 10 issues a command at the internal address of the virtual device. The command is issued to the virtual device a, the virtual device b, or the virtual device n.

A command receiving unit 14 receives a command or the like issued from the channel control unit 20. Reference numeral 20 denotes a channel controller, which is an input / output device 2
5 for channel control.

Reference numeral 21 is a command transfer unit, which receives a command issued by the input / output control unit 5
5 is to be transferred. The command transfer unit 21 converts the internal address of the command issued by the input / output control unit 5 into the real address of the input / output device 25, attaches an arbitrary command identification number, and transfers the command to the input / output device 25.

Reference numeral 25 is an input / output device. Reference numeral 26 is a command receiving unit, which has a plurality of queues and receives a command issued by the channel control unit 20.
It can accept multiple commands at the same time.

Reference numeral 31 denotes a virtual device a, which is an input / output device 2
The specific area of 5 is regarded as a virtual device. 32
Is a virtual device b, in which a specific area of the input / output device 25 is regarded as a virtual device.

Reference numeral 33 denotes a virtual device n, which is an input / output device 2
The specific area of 5 is regarded as a virtual device. FIG.
The operation of the basic configuration (1) of the present invention will be described.

When a command is received from a device (not shown) on the application program side, or when a command issued by the input / output device 25 is received from the channel controller 20, the input / output controller 5 issues the command. When required, the komat issuing unit 10 issues a command to the virtual device a, the virtual device b, or the virtual device n. The command is issued by an internal address in the virtual device.

In the channel control unit 20, the command transfer unit 21 converts the internal address of the command received from the input / output control unit 5 into the real address of the input / output device. The command issued by the channel controller 20 is transferred to the input / output device 25. At that time, the command is transferred with an arbitrary command identification number. The command identification number is stored in the channel controller 20 in association with the virtual device name.

When the input / output device 25 receives a command from the channel controller 20, the input / output device 25 processes the command in the virtual device a, the virtual device b, or the virtual device n according to its real address.

The input / output device 25 attaches the command identification number of the processed command and issues a command responding to the command (command processing end command, etc.). The command is sent to the channel control unit 20, and the correspondence between the command identification number and the virtual device name held in the channel control unit 20 is referenced to obtain the virtual device name. The channel control unit 20 issues a command by the virtual device name and transfers it to the input / output control unit 5. The command is received by the command receiving unit 14, and the command issuing unit 10 issues a command responding to the command or terminates the virtual device. Alternatively, the command is issued to the channel control unit 20 or a device (not shown) on the application program side.

FIG. 2 shows a basic configuration (2) of the present invention (corresponding to claims 1, 4, and 5). In FIG. 2, reference numeral 1 is an input / output control device.

Reference numeral 5 is an input / output control unit. Reference numeral 10 denotes a command issuing unit, which is used when a command is issued from a device (not shown) on the application program side or when a command is received from the channel control unit 20. Is issued.

The command issuing unit 10 selects a virtual device that is not being executed and issues a command to the selected virtual device. Reference numeral 14 is a command receiving unit.

Reference numeral 20 denotes a channel controller which transfers the command received from the input / output controller 5 to the input / output device 25. Reference numeral 21 denotes a command transfer unit, which transfers the command received from the input / output control unit 5 to the input / output device 25. The command transfer unit 21 refers to the virtual device identification number holding unit 23 and attaches a command identification number determined for each virtual device to the command and issues the command.

Reference numeral 23 is a virtual device identification number holding unit,
It has a correspondence between a virtual device name and an identification number (which is fixed for the virtual device name). Reference numeral 25 is an input / output device.

A command receiving unit 26 has a queue 1, a queue 2, ..., A queue n, and can receive a plurality of commands in parallel with the processing. The operation of the basic configuration of the present invention shown in FIG. 2 will be described.

When it is necessary to generate a command by receiving a command from a device (not shown) on the application program side or by receiving a command by the command receiving unit 14, the command issuing unit 10 issues a command. To do.

The command issuing unit 10 selects a virtual device that is not being executed and issues a command to the virtual device. The command is transferred to the channel controller 20. In the channel control unit 20, the command transfer unit 21 refers to the virtual device identification number holding unit 23, attaches the command identification number to the command, and issues the command by the real address of the input / output device 25.

In the input / output device 25, the command is received by the command receiving unit 26 and held in the queue.
The commands are processed in the order in which they are received or, if necessary, rearranged in the order of addresses and so on. When the command processing is completed, the command is issued from the input / output device 25 to the channel controller 20. The command is issued with the command identification number attached to the command processed at that time. The channel control unit 20 refers to the virtual device identification number holding unit 23, obtains a virtual device corresponding to the command identification number, and issues a command to the input / output control unit 5. The command is received by the command receiving unit 14, and a command responding to the virtual device is issued, or termination processing for the virtual device is performed.

FIG. 3 shows a basic configuration (3) of the present invention (corresponding to claim 6). Reference numeral 50 is the host computer 0. Reference numeral 60 is the host computer 1.

In the host computer 0 (50), 51
Is a command issuing unit that generates a command with a tag number.

Reference numeral 52 is a tag number generator, which generates a tag number. For example, host computer 0
(50) uses 0 to m as the tag number. 5
A tag number range holding unit 3 holds the tag number range. For example, the tag number range is 0 to
It holds m.

Reference numeral 54 designates a tag selecting section, which is an input / output device 7
It refers to the tag number of the command issued from 0 and selects the tag issuing command in the range of the tag number range holding unit 53.

In the host computer 1 (60), 61
Is a command issuing unit that generates a command with a tag number.

Reference numeral 62 is a tag number generating section for generating a tag number. For example, host computer 1
(60) uses (m + 1) to N as tag numbers.

Reference numeral 63 is a tag number range holding unit, which holds the tag number range. For example, it holds (m + 1) to N as the tag number range. 64
Is a tag selection unit that refers to the tag number of the command issued from the input / output device 70,
The command for issuing a tag within the range is selected.

Reference numeral 70 is an input / output device. Reference numeral 71 denotes a command receiving unit, which includes a queue 1, a queue 2, ..., A queue n. By receiving commands and holding them in the queue, multiple commands can be received simultaneously.

Reference numeral 75 is a command issued by the host computer 0 (50), which includes tag information (0 to m). Reference numeral 76 is a command issued by the host computer 1 (60), which includes tag information ((m + 1) to N).

Reference numeral 77 is a command issued from the input / output device and having a tag number. The operation of the basic configuration (3) of the present invention in FIG. 3 will be described.

In the host computer 0 (50), when issuing a command, the tag number generator 52 generates the tag numbers in the range held in the tag number range holder 53. The command issuing unit 51 issues a command by attaching a tag number to the command (see command 75). The tag number of the command issued by the host computer 0 (50) is in the range of 0 to m.

Similarly, when a command is generated in the host computer 1 (60), the tag number generation unit 62 refers to the tag number range holding unit 63 and generates a tag number. The range of tag numbers generated by the host computer 1 (60) is (m
+1) to N.

The command issuing unit 61 adds a tag number ((m + 1) to N) to the command to generate the command (see command 76). The command 75 and the command 76 are transferred to the input / output device 70 and held in the queue of the command receiving unit 71. Then, the command is executed.

The same tag number as the received command is attached to the command issued from the input / output device 70, such as the command completion report, and each host computer (5
0, 60) (see command 77) When the host computer 0 (50) receives the command, the tag selection unit 54 compares the tag number range of the tag number range holding unit 53 with the tag number of the received command. However, if it is within the range of the tag number range holding unit 53, it is determined that the command is addressed to itself, and internal processing is performed. If the number is outside the range of the tag number range holding unit 53, it is not selected.

Similarly, when the host computer 1 (60) receives a command, the tag selection unit 64 compares the tag number range of the tag number range holding unit 63 with the tag number of the received command, and the tag number range holding unit 63. If it is within the range of, the command is determined to be addressed to itself, and internal processing is performed. If the number is outside the range of the tag number range holding unit 63, it is not selected.

[0051]

According to the present invention, the device on the application program side can issue a command in the same manner as an ordinary one-to-one correspondence input / output device to access an input / output device which accepts a plurality of commands. Becomes Further, the input / output control device can control an input / output device capable of accepting a plurality of commands only by issuing a command while being aware of only the virtual device name. Further, according to the basic configuration (3) of the present invention, even if commands are simultaneously issued from a plurality of host computers, the issuing host computer can be identified by the tag number, so that a plurality of commands can be simultaneously accepted with a simple configuration. Access to the available I / O devices.

Therefore, according to the present invention, it becomes possible to efficiently control the input / output device that receives a plurality of commands.

[0053]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic disk device will be described below as an example of an input / output device. FIG. 4 shows the first embodiment of the present invention.

In FIG. 4, reference numeral 80 is an input / output control device. Reference numeral 85 is an input / output control unit.

A virtual device information holding unit 86 holds the correspondence between the virtual device name and the real address of the magnetic disk device 110. 87 is a command issuing unit.

Reference numeral 87 'is a virtual device name determination unit which determines the virtual device name based on the real address of the command. Reference numeral 88 denotes a processing unit of the virtual device a, which is a processing unit for obtaining an internal address (relative address) of the virtual device a based on the real address.

Reference numeral 89 is a processing unit of the virtual device b, which obtains the internal address (relative address) of the virtual device b based on the real address. Reference numeral 90 denotes a processing unit of the virtual device c, which is a processing unit for obtaining an internal address (relative address) of the virtual device c based on the real address.

Reference numeral 91 is a command issuance determination unit, which determines whether the queue of the magnetic disk device (110) is available. A command receiving unit 92 receives a command transferred from the channel control unit 95.

Reference numeral 95 is a channel controller. A virtual device real address holding unit 96 holds a start real address of the virtual device.

Reference numeral 97 is a command transfer section. The command transfer unit 97 refers to the real address holding unit 96 of the virtual device and converts the internal address attached to the command into the real address of the magnetic disk device. Then, the command is issued with an arbitrary command identification number. The command identification number is temporarily stored in the command identification number storage unit 101 in association with the virtual device name of the command.

Reference numeral 98 denotes a processing unit of the virtual device a, which performs the above-mentioned command issuing process (process of the command transfer unit 97) for the command issued to the virtual device a.

Reference numeral 99 denotes a processing unit of the virtual device b, which performs a command issuing process for a command issued to the virtual device b. Reference numeral 100 denotes a processing unit of the virtual device c, which performs a command issuing process for a command issued to the virtual device c.

Reference numeral 102 is a command transmission / reception unit. The command issued by the magnetic disk device 110 is given the command identification number of the processed command, and the channel control unit 95
The command transfer unit 97 refers to the command identification number holding unit 101 to obtain the virtual device name from the command identification number of the received command, attaches the virtual device name to the command, and sends the command to the input / output control unit 85. Transfer (or, if a virtual device is determined, transfer is performed through the route of the processing unit (88, 89, 90) of the virtual device).

Reference numeral 102 'denotes a queue status information transfer section for transferring status information indicating the availability of the queue to the input / output control section 85. Reference numeral 110 is a magnetic disk device.

Reference numeral 111 denotes a command receiving section, which receives a command issued by the channel control section 95. The command accepting unit 111 has a plurality of queues,
It can receive multiple commands at the same time.

Reference numerals 112, 113 and 114 are elements (one command). Reference numeral 115 denotes a command array changing unit for changing the order of commands held in the queue (for example, changing the commands held in the reception order to the address order in which the commands are handled).

Reference numeral 120 is an area corresponding to the virtual device a. Reference numeral 121 is an area corresponding to the virtual device b. 122
Is an area corresponding to the virtual device c.

The operation of the configuration of FIG. 4 will be described later. FIG. 5 is a configuration example of commands and various holding units according to the first embodiment of the present invention. In FIG. 5, reference numeral 202 denotes a command issued by the input / output control unit, which is a command (command code),
It includes internal address and data length.

Reference numeral 203 denotes a command issued by the channel controller, which includes a command (command code), a command identification number, a real address of the magnetic disk device, and a data length.

Reference numeral 86 is an example of a virtual device information holding unit in the input / output control unit 85, which holds the correspondence between the real address range of the magnetic disk device and the virtual device name. 96
Is a real address holding unit of the virtual device in the channel control unit 95, and holds the correspondence between the start address of each virtual device and the real address of the magnetic disk device.

Embodiment 1 of the present invention shown in FIG. 4 according to FIGS. 6 and 7.
Will be described. FIG. 6 is a flowchart of the command issuing unit of the input / output control unit according to the first embodiment of the present invention.

The flow chart of the command issuing unit of the first embodiment will be described according to the numbers of the steps shown. A command issuance request is accepted from a device (not shown) on the S1 application program side.

In the S2 command issuing unit 87, the virtual device name determining unit 87 'refers to the virtual device information holding unit 86,
The virtual device name etc. is obtained based on the real address of the command. When the target of the S3 and S4 commands is the virtual device a, the real address is converted into the internal address of the virtual device a.

The target of the S3 and S5 commands is the virtual device b.
, The real address is converted into the internal address of the virtual device b. When the target of the S3 and S6 commands is the virtual device c, the real address is converted to the internal address of the virtual device c.

S7, S8 Command issuance propriety determination unit 9
Refer to 2 to determine whether the command can be accepted. If there is no space in the queue of the magnetic disk device (110) to accept the command, it waits until the queue becomes empty.

S9: If the magnetic disk device (110) can accept the command, the command for the virtual device is transferred to the channel device. FIG. 7 is a flowchart of the command transfer unit of the channel control unit according to the first embodiment of the present invention.

S1 A command issuance request from the input / output control unit 85 is accepted. The command for the virtual device a is processed by the processing unit 98 of the virtual device a. The command for the virtual device b is processed by the processing unit 99 of the virtual device b. The command for the virtual device c is the processing unit 100 of the virtual device c.
Is processed in.

The internal address of each virtual device is converted into the real address of the magnetic disk device 110 by referring to the real address holding unit 96 of the S2 virtual device. S3 Each virtual device processing unit (98, 99, 10
0) attaches an arbitrary command identification number to the command.

S4 The processing unit (9
8, 99, 100) holds the correspondence between the command identification number and the virtual device name in the command identification number holding unit 101. S5 The command is transferred to the magnetic disk device 110.

In the configuration of FIG. 4, when the command processing is completed in the magnetic disk device, for example, an end command is issued. The command issued in the magnetic disk device 110 is issued with the command identification number of the processed command. To do. The command is the channel control unit 9
The command transmitting / receiving unit 102 of No. 5 refers to the command identification number holding unit 101, obtains the virtual device name corresponding to the command identification number, and transfers it to the command receiving unit 92 of the input / output control unit 85. Alternatively, it is transferred to the processing unit (88, 89, 90) of the virtual device by the route of the processing unit (88, 89, 90) of the virtual device.

Then, in the input / output control unit 85, the processing unit (88, 89,
90) performs processing for the virtual device (issue of new command, end processing, etc.).

FIG. 8 shows a second embodiment of the present invention. In FIG. 8, reference numeral 80 is an input / output control device.

Reference numeral 85 is an input / output control unit. A command issuing unit 87 issues a command to the virtual device selected by the virtual device selecting unit 87 ″.

A virtual device selection unit 87 "selects a virtual device which is not being executed based on the queue information. Further, the virtual device selection unit 87" is a channel control unit 9.
5 selects the virtual device to be the target of the command transferred from 5.

Reference numeral 88 is a processing unit of the virtual machine a. 89 is a processing unit of the virtual device b. Reference numeral 90 is a processing unit of the virtual device c.

A virtual device status information holding unit 93 holds information about virtual devices that are not being executed based on the queue information sent from the magnetic disk device 110.

Reference numeral 95 is a channel controller. A command transfer unit 97 issues a command to the magnetic disk device 110 with a command identification number of a virtual device.

A command transmitting / receiving unit 102 receives a command issued by the magnetic disk device 110, refers to the command identification number holding unit 103 of the virtual device, and identifies the virtual device name of the command by the command identification number. I / O control unit 8
5 (or the command is transferred to the virtual device processing unit (88, 89, 90) obtained by the route to the virtual device processing unit (88, 88, 90)).

Reference numeral 103 denotes a command identification number holding unit of the virtual device, which holds the virtual device name and the command identification number in association with each other. A virtual device status information transfer unit 104 transfers the virtual device status information sent from the magnetic disk device 110 to the input / output control unit 85.

Reference numeral 110 is a magnetic disk device. 111
Is a command receiving unit. Reference numeral 115 is a command arrangement changing unit.

The operation of the configuration of FIG. 8 will be described later. FIG. 9 shows an example of a command configuration and an example of a command identification number holding unit of a virtual device according to the second embodiment of the present invention.

In FIG. 9, reference numeral 222 denotes an input / output control unit 85.
Is a command issued in step 1, and includes the command, the real address of the magnetic disk device, and the data length.

A command 223 is issued by the channel controller 95 and includes a command, a command identification number of a virtual device, a real address, and a data length. Reference numeral 103 denotes a command identification number holding unit of the virtual device, which fixes a command identification number 1 for the virtual device name a, a command identification number 2 for the virtual device name b, and a command identification number 3 for the virtual device name c. It has something to do with it.

The operation of the second embodiment shown in FIG. 8 will be described with reference to FIGS. FIG. 10 is a flowchart of the command issuing unit of the input / output control unit according to the second embodiment of the present invention.

It is necessary to issue a command by issuing a command from the device on the S1 application program side. The S2 virtual device selection unit 87 "refers to the virtual device state information holding unit 93 and determines an empty virtual device.

S3 The virtual device name of the selected virtual device is added, and the command is issued by the real address of the magnetic disk device. FIG. 11 is a flowchart of the command issuing unit of the channel control unit according to the second embodiment of the present invention.

S1 A command is sent from the input / output control unit 85, and the processing unit (98, 9) of each virtual device is sent.
9,100) receives the command. The processing unit of the virtual device that has received the S2 command (98,
(99, 100), the command identification number is obtained by referring to the command identification number holding unit 103 of the virtual device.

S3: The command identification number of the virtual device obtained is added to the command, and the command is issued by the real address and transferred to the magnetic disk device 110. When a command is issued from the magnetic disk device 110, it operates as follows.

For example, it is assumed that the command processing is completed in the magnetic disk device 110 and the command end command is issued. The magnetic disk device 110 attaches the command identification number of the processed command and issues an end command to the channel controller 95.

In the channel control unit 95, the command transmitting / receiving unit 102 uses the command identification number holding unit 10 of the virtual device.
3, the virtual device name corresponding to the command identification number is obtained. Then, the virtual device name obtained for the end command is transferred to the input / output control unit 85 (or the virtual device processing unit obtained by the route to the virtual device processing unit (88, 89, 90)). (Transfer the command to (88, 89, 90)).

The input / output control unit 85 processes the command (end command or the like) in the processing unit (88, 89, 90) of the virtual device that processes the command. For example, if it is a termination command, termination processing of the virtual device is performed.

[0102]

According to the present invention, the device on the application program side is capable of accepting another command even during command processing, with respect to an input / output device.
Commands can be issued in the same way as for a normal one-to-one correspondence input / output device. Therefore, according to the present invention, it becomes possible to easily control the input / output device that receives a plurality of commands.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration (1) of the present invention.

FIG. 2 is a diagram showing a basic configuration (2) of the present invention.

FIG. 3 is a diagram showing a basic configuration (3) of the present invention.

FIG. 4 is a diagram showing a configuration of a first embodiment of the present invention.

FIG. 5 is a configuration example of commands and various holding units according to the first embodiment of the present invention.

FIG. 6 is a flowchart of a command issuing unit of the input / output control unit according to the first embodiment of the present invention.

FIG. 7 is a diagram showing a flowchart of a command transfer unit of the channel control unit of the present invention.

FIG. 8 is a diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 9 shows an example of a command configuration and an example of a command identification number holding unit of a virtual device according to the second embodiment of the present invention.

FIG. 10 is a flowchart of a command issuing unit of the input / output control unit according to the second embodiment of the present invention.

FIG. 11 is a diagram showing a flowchart of a command issuing unit of the channel control unit according to the second embodiment of the present invention.

FIG. 12 is a diagram showing a configuration of a conventional magnetic disk device and an input / output control device.

[Explanation of symbols]

 1: I / O control device 5: I / O control unit 10: Command issuing unit 14: Command receiving unit 20: Channel control unit 21: Command transfer unit 25: I / O device 26: Command receiving unit 31: Virtual device a 32: Virtual Device b 33: Virtual device n

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshiro Hirai, Yoshiro Hirai, 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa, Fujitsu Limited 72) Inventor Masao Yamamoto 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited

Claims (6)

[Claims] 1. In an input / output control device of an input / output device capable of accepting a command even during command processing, the input / output control device controls a channel connecting the input / output control unit and the input / output device. And a control unit,
The input / output control unit regards the input / output device as a plurality of virtual devices and issues a command to the virtual devices. 2. The I / O control unit regards a plurality of areas of the I / O device as virtual devices, issues a command by the internal address of the virtual device, and the channel control unit receives the command received from the I / O control unit. The input / output control device according to claim 1, wherein an internal address in the virtual device is converted into a real address and a command is issued to the input / output device. 3. A channel control unit attaches an arbitrary command identification number to a command issued to an input / output device, issues the command, and controls the correspondence between the command identification number and the virtual device name processed by the command. The input / output control device according to claim 2, wherein the input / output control device is held by a unit. 4. The input / output control unit names a plurality of virtual device names for the input / output device, holds status information of each virtual device,
2. The input / output control device according to claim 1, wherein a virtual device that is not executing a command is selected and a command is issued to the selected virtual device. 5. A device corresponding to a virtual device, wherein the channel control unit holds the correspondence between a virtual device and its device identification number, and when a command issued by the I / O control unit is received, the command is processed by the I / O device. The input / output control device according to claim 4, wherein the command is issued by the identification number and the real address. 6. An input / output control device of an input / output device capable of receiving a command even during command processing, wherein a plurality of computers are connected to the input / output device, and the computer device transfers the input / output device to the input / output device. I / O, in which a command is issued with a tag attached, and a range of tag numbers that is different for each computer is defined, and the computer sets a tag number within the defined tag number range to the command. Control device.