JPH0640299B2 - Peripheral device Medium input processing control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] In a data processing system in which a peripheral device for automatically loading a storage medium such as a cartridge or tape and inputting / outputting data is shared by a plurality of host processing devices, a medium is loaded into the peripheral device. When an attention interrupt is sent to all host processors, the DASD shared between systems will be processed.
By using the inter-system exclusive control function of (Direct Access Storage Device), serialization and inter-host exclusive control are possible.

[Industrial application field]

The present invention relates to a method of controlling a peripheral device having an automatic loading mechanism of a storage medium for recording data in a so-called loosely coupled multiprocessor system, and more particularly, an attention interrupt notified to all host processing devices by inserting a medium. The present invention relates to a peripheral device medium loading process control method for performing exclusive control between hosts for the above process.

[Conventional technology]

A mass storage system (MSS) is known as a peripheral device having an automatic loading mechanism of a storage medium for recording data. The loading process and the discharging process of the data cartridge in the mass storage system are performed by the firmware in the mass storage system. Therefore, in the conventional large-capacity storage system, it is not necessary to perform exclusive control between a plurality of host processing devices with respect to medium loading processing, ejection processing, and the like.

An inter-system exclusive control device (adapter) connected to a channel or an input / output control device is known as an exclusive control mechanism for shared DASD between systems, that is, between host processors, and a so-called reserve (RSV) command is used. When the issuing host processor occupies the shared DASD and issues a release (RLS) command, the occupancy is released.

[Problems to be solved by the invention]

By the way, in a peripheral device with an automatic medium loading mechanism, if the loading and ejecting processes of the medium are all executed by the firmware regardless of the control by the host processing device, for example, the peripheral device is replaced with the conventional magnetic tape. When it is used like a device, it becomes difficult for the host processor to manage and control it precisely. Therefore, a new peripheral device has been considered in which the host processor directly processes the medium loading process, the medium discharging process, and the like without using firmware.

In this peripheral device, when a storage medium is loaded, the host processing unit is notified of the loading of the medium by an attention (Att) interrupt. When the host processing device receives this attention interrupt, it executes a medium loading process such as determining the medium storage position, reading the volume label, etc., registering it in the management table, and moving / storing it in the medium storage.

When such a peripheral device with an automatic medium loading mechanism is shared by a plurality of host processing devices, an attention interrupt due to the insertion of a medium is notified to all host processing devices. Therefore, all the host processing devices will perform the medium input process due to the attention event almost at the same time, and the competition of the devices will occur. There is a problem of causing a system malfunction such as being processed by.

However, if this attention interrupt is notified only to a specific one host processor, exclusive control is unnecessary, but when a plurality of attention events occur, each host processor responds to those attention events. A new problem arises in that the processing cannot be distributed and executed, resulting in poor efficiency. In addition, interposing an inter-system exclusive control device, such as that used in the inter-system shared DASD, between each host processor and the peripheral device with the automatic media loading mechanism is generally to access the peripheral device with the automatic media loading mechanism. This is not appropriate considering that the time is longer than DASD.

[Means for solving problems]

The present invention solves the above problems and provides a control system in which only one of the host processing devices processes one event of media loading attention to all host processing devices sharing a peripheral device with an automatic media loading mechanism. To do.

FIG. 1 shows the basic configuration of the present invention.

The host processing devices 11A and 11B are data processing devices each having a main storage device and loosely coupled by a shared peripheral device. The attention interrupt reception unit 12 is an appendage routine activated by an attention interrupt from a peripheral device. This appendage routine can be registered for each device, but since it is a well-known technique, detailed description thereof will be omitted.

The medium loading processing unit 13 is activated by the attention interrupt receiving unit 12 in response to an attention interrupt caused by loading a medium, and performs processing relating to this attention event. Exclusive control processing unit 14 and medium loading processing execution unit 15
It has and.

The exclusive control processing unit 14 performs exclusive control for the medium loading process so that competition with other host processing devices does not occur. Under the exclusive control of the exclusive control processing unit 14, the medium insertion processing execution unit 15 determines the medium storage position, reads the volume label, etc., registers it in the management table, and moves / stores the medium in the medium storage. This is to execute the input process.

The peripheral device 16 with an automatic medium loading mechanism is a peripheral device having a mechanism for automatically loading a storage medium such as a data cartridge, inputting / outputting data from the medium, and storing the medium in an internal storage. It is a device.

The medium loading / unloading mechanism (TAS) 17 is a mechanism for receiving a medium loaded by the operator into the peripheral device 16 and discharging a used medium. A sensor for detecting the input of the medium is provided, and when the input of the medium is detected, an attention interrupt is given to all the host processing devices such as the host processing device 11A and the host processing device 11B. The automatic medium operation unit (THU) 18 is a device for moving a medium in the peripheral device 16 and automatically loading the medium. Medium storage (CELL)
Reference numeral 19 denotes a mechanism for storing the medium, and the medium automatic operation device 18 automatically takes in and out the medium. Data input / output unit (MTU) 20-1,
Reference numerals 20-2, ... Are devices for recording data on a medium or reading data recorded on the medium. This data input / output device can be installed in one peripheral device 16, for example, up to 16 devices.

The inter-system exclusive control device 21 is an adapter that performs exclusive control regarding access between host processing devices to a device connected under it. As is well known, only a host processor that has occupied a device by a reserve (RSV) command requesting the device to be occupied allows access to the device, and a release (RLS) command releases the device. That is, it can be considered that the inter-system exclusive control device 21 functions as a connection switch for the subordinate devices.

The inter-system shared DASDs 22-1, 22-2, ... Are storage devices such as magnetic disk devices that are directly accessed, and are peripheral devices that can be accessed by a plurality of host processing devices. The management table 23 is a table for storing management information regarding the storage medium accommodated in the peripheral device 16 with the automatic medium loading mechanism.

According to the present invention, when performing the exclusive control of the medium loading process, the exclusive control processing unit 14 uses the function of the inter-system exclusive control device 21 to reserve the inter-system shared DASD 22-1, thereby performing the process for the attention event. Perform serialization.

[Action]

When a medium is loaded into the peripheral device 16 with the automatic medium loading mechanism, an attention interrupt is generated and the host processor 11A, 1
1B ... is notified. In each host processing device, the exclusive control processing unit 14 uses the intersystem shared D having the management table 23.
Issue a reserve command to the ASD 22-1.
By the inter-system exclusive control device 21, only one host processing device can occupy the inter-system shared DASD 22-1 at one time point, and the other host processing devices are kept waiting until the occupancy is released. As a result, the medium loading process can be serialized.

〔Example〕

FIG. 2 is a diagram for explaining processing control according to an embodiment of the present invention. For the sake of simplicity, the case where there are two host processing devices will be described below, but the same processing is performed when there are three or more host processing devices.

In FIG. 2, when a medium (cartridge) is loaded into the peripheral device 16 with an automatic medium loading mechanism from the cartridge inlet, the host processing device 11A and the host processing device 11
Attention interrupt is notified to B. The host processors 11A and 11B receive the attention interrupt,
A reserve command is issued to the inter-system shared DASD 22-1.

First, it is assumed that the A-system host processing device 11A succeeds in the reserve. The host processing device 11A then issues a command to read the state of the peripheral device 16 with the automatic medium loading mechanism, and checks whether or not there is an attention event related to medium loading. In this case, since it is the first process, there is an attention event.

When it is confirmed that there is an attention event, one volume of the data input / output unit (MTU) is secured to read and check the volume label of the loaded cartridge, and the medium loading / unloading mechanism is set by the medium automatic operation unit 18. 1
Move the cartridge from 7 and load it in the reserved MTU. Then, the inter-system shared DASD 22-1 is released to release the occupation. After that, the volume label or the like is input, the storage home cell in the medium storage 19 is determined, necessary information is registered in the table, the cartridge is moved to the home cell, and the processing for one attention event is completed.

On the other hand, in the host processing device 11B, since the host processing device 11A first occupies the inter-system shared DASD 22-1, the reservation of the inter-system shared DASD 22-1 becomes unsuccessful, and the host processing device 11B enters the reservation release waiting state.

When the host processor 11A cancels the reservation, the cancellation is notified by a so-called busy-to-free interrupt. Therefore, the inter-system shared DASD 22-1 is secured again, and the states of the medium ejecting mechanism and the medium automatic operating device are read. The command checks whether there is an attention event. In this example, since the host processing device 11A has already started the medium input process for the attention interrupt, the attention event has disappeared, and the host processing device 11B releases the inter-system shared DASD 22-1 to execute the actual operation. The process ends without executing the medium loading process.
As a result of checking the attention event, if there is another attention event, the processing for the attention event is executed and the inter-system shared DASD 22-1 is released. Then, the same processing is repeated until the attention event disappears.

〔The invention's effect〕

As described above, according to the present invention, it is possible to exclusively control the medium loading process for the attention event of the peripheral device with the automatic medium loading mechanism between the host processing devices. Further, when a plurality of attention events occur, it becomes possible for each host processing device to dispersively execute the processing for the attention event.

Since the inter-system exclusive control device for the existing inter-system shared DASD is used for the inter-host exclusive control, no new exclusive control mechanism hardware is required.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of the present invention, and FIG. 2 is a process control explanatory diagram according to an embodiment of the present invention. In the figure, 11A and 11B are host processing devices, 13 is a medium loading processing unit, 14 is an exclusive control processing unit, 15 is a medium loading process executing unit, 16 is a peripheral device with an automatic loading mechanism, and 21 is an intersystem exclusive control. Equipment, 22-1, 22-2 are shared DA between systems
Represents SD.

Claims (1)

[Claims] 1. A plurality of host processing devices for processing data (1
1A, 11B, ...), a peripheral device (16) with a medium automatic loading mechanism that causes an attention interrupt to each of the host processing devices when a medium is input, and a system shared by the plurality of host processing devices. In a data processing system comprising a shared DASD (22) and an intersystem exclusive control device (21) interposed between the host processing device and the intersystem shared DASD to perform exclusive control of the intersystem shared DASD, Each of the host processing devices includes a medium loading processing unit (13) that performs processing for an attention interruption caused by loading a medium into the peripheral device with the automatic medium loading mechanism, and the medium loading processing unit is for the intersystem exclusive control. There is a means (14) for reserving the inter-system shared DASD using the device and an attention event when the inter-system shared DASD is successfully reserved, and there is an attention event due to medium insertion. And a means (15) for executing the medium loading process when the above reserve is released, and an intersystem exclusive control device for exclusive control of the medium loading process to the peripheral device with the automatic media loading mechanism for the intersystem shared DASD. Peripheral device medium loading process control method characterized in that it is performed by using exclusive control by.