JPH09146871A - Arbitrary message data decision system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate unnecessary message exchange resulting from the transmission of an unsupported message and make a process itself in case of abnormality occurrence simple. SOLUTION: A message information storage register 21 stores an arbitrary message group that a SCSI controller in target operation supports by ID information and an ID information management mechanism 22 sends out ID information on a SCSI controller in the target operation at a connection destination when a SCSI controller 2 in initiator operation is executing the operation of a SCSI bus 1. An arbitrary message judgement part 23 judges an arbitrary message effective bit indicating that the SCSI controller 2 in initiator operation is executing the operation of the SCSI bus 1 and an arbitrary message group that the SCSI controller in target operation supports according to the ID information sent out by the ID information managing function 22 and stores them in a support message storage register 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for discriminating arbitrary message data, and more particularly to SCSI (SmallComp).
The present invention relates to a method for discriminating arbitrary message data at the time of data transfer in transmission of an arbitrary message in a SCSI controller of an initiator operation based on the Uter System Interface standard.

[0002]

2. Description of the Related Art As is well known, SCSI is a SASI (Shugar) device devised by Sugarto Corporation in the United States as an interface for connecting a small computer and its peripheral devices.
t Associates System Inter
interface), and the standardization of the interface protocol. The ANSI (American National Standards Institute) standardized X3.
Deliberated by T9.2 Working Committee ANSI X3.131
-1986, which is currently the most general-purpose interface for connecting a personal computer and its peripheral devices.

In SCSI, an ID (IDen) is provided as an identification number for each SCSI controller connected to the SCSI bus.
SCSI information from this ID information.
It enables a SCSI controller connected on the bus to function as an initiator or a target.

There are eight types of phases in the operation of the SCSI bus. That is, SCSI on the SCSI bus
The bus free phase when the controller is not using the bus, the arbitration phase for the SCSI controller to acquire the right to use the bus as an initiator or target, and the SCSI controller that operates as a target (hereinafter, target operation). SCSI
SCS operating as a controller)
A selection phase for the I controller (hereinafter referred to as the initiator operating SCSI controller) to select,
This is a phase for selecting the SCSI controller of the initiator operation from the SCSI controller of the target operation. The SCSI controller of the target operation is the reselection phase used when restarting the processing of the command in the disconnected state, and the initiator. SCS of operation
A command phase for transferring a command designating an input / output operation from the I controller to the target operating SCSI controller, and a data phase for transferring data between the initiator operating SCSI controller and the target operating SCSI controller And a status phase in which the status is transferred from the target operating SCSI controller to the initiator operating SCSI controller at the end of command execution, and a message is sent between the initiator operating SCSI controller and the target operating SCSI controller. There are message phases to transfer.

Since the SCSI controller of the target operation manages the phase transition as described above, the SCSI controller of the initiator operation and the SCSI controller of the target operation operate.
Information is exchanged with the control device.

Here, the message in the above message phase will be described. The message is the SCSI controller for the initiator operation and the S for the target operation.
It is information for interface management with the CSI controller, and defines a mandatory message that must be supported by the SCSI controller and an optional message that can be optionally supported by each SCSI controller. ing. Optional messages include SCSI bus management, bus usage, and messages that notify the occurrence of abnormalities. By supporting these optional messages, for example, during synchronous transfer in the data phase and during data transfer. Data transfer can be re-executed when a parity error occurs. Further, since it is optional for each SCSI control device to support the optional message, it is not necessary to support the optional message at all.
It is not possible to re-execute data transmission / reception when data is transmitted / received to / from a SCSI control device that does not internally retain the data once it has been transmitted, because no notification can be given regarding abnormalities that occur during operation of the CSI bus. There is a nature.

In addition, when supporting an arbitrary message, the SCSI control device indicates that the last received message is an unsupported MESSAGE RE.
It must support JECT messages. This is the SCSI connected on the SCSI bus.
When the optional message supported by each control device is different, an unsupported message may be received by the own SCSI control device within the message phase. This is because it is necessary to notify the control device. Thus, any SCSI controller that supports arbitrary messages must be MESSAGE REJECT.
By supporting messages, even when the SCSI control devices connected to the SCSI bus individually support arbitrary messages, it is possible to send and receive messages without any problem in the message phase.

[0008]

However, in the above-mentioned conventional method, when the SCSI controller of the initiator operation sends an arbitrary message of abnormality notification as abnormal processing when some abnormality occurs, the transmitted arbitrary message May not be supported by the SCSI controller of the target operation of the connection destination, so MESSAGE
The processing when the REJECT message is returned must be taken into consideration, and there is a problem that the processing of the abnormal system swells.

An example of the operation in such a case is shown in FIG.
FIG. 5 shows an SCS of the initiator operation when a message is transmitted and received between the SCSI controller of the initiator operation and the SCSI controller of the target operation of the connection destination.
Since the I controller has detected a data parity error in the data phase, it is an optional message INITIATOR DETE that notifies the SCSI controller of the target operation of the connection destination that a parity error has occurred.
It is the flowchart which showed the process example in the case of sending out a CTED ERROR message.

First, the SCSI controller of the initiator operation notifies the fact that a parity error is detected, so that an INITIATOR DET which is an optional message is sent.
The processing for transmitting the ECTED ERROR message is executed (step S201).

However, INITIATOR DETEC
Since the TED ERROR message is not always supported by the target operation SCSI controller to which it is connected, the initiator operation SCSI controller may
A process of confirming whether or not the next phase is a message in phase after sending the ITITOR DETECTED ERROR message (step S202),
If the next phase is the message in phase, the SCSI controller of the target operation of the connection destination connects to MESS
Since the AGE REJECT message may be sent, the process of receiving the message (step S20
3) and must be added.

In addition, an initiator-operated SCSI controller is an INITIATOR DETECTED ERR.
After sending the OR message, S of the target operation of the connection destination
If the CSI controller sends the MSSAGE REJECT message (YES in step S204), it is necessary to send the other arbitrary message to notify the abnormality. Therefore, in this processing example, the ABORT message that is an arbitrary message is sent. Is executed (step S205).

Here, as before, since the ABORT message is not always supported by the SCSI controller of the target operation of the connection destination, the SCSI controller of the initiator operation does not support the ABORT message after sending the ABORT message.
Processing for confirming whether the next phase is the message-in phase (step S206), and if the next phase is the message-in phase, the SCSI controller of the target operation of the connection destination connects to the MESSAGE REJ.
Since the ECT message may be transmitted, it is necessary to add a process of receiving the message (step S207).

After sending the ABORT message,
Connected target operation SCSI controller to MES
When the SAGE REJECT message is sent (YES in step S208), in this processing example, a process of issuing a RESET signal on the SCSI bus as another abnormal process without sending an arbitrary message indicating an abnormal notification (step S210) I do.

In this way, the SCSI of the initiator operation
When the control device sends an arbitrary message, the confirmation process of the next phase (steps S202 and S206) and the process of receiving the message (steps S203 and S20) are always performed.
7) and the process (step S205) of sending another arbitrary message indicating an abnormal notification when the sent arbitrary message is an unsupported message in the SCSI controller of the target operation of the connection destination. However, there is a factor that the abnormal processing swells and the use efficiency of the SCSI bus decreases due to useless message exchange when an unsupported message is sent.

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, an object of the present invention is to provide, in an initiator-operated SCSI controller, a target-operated SCSI controller which is connected to the same SCSI bus. Even if it supports messages, by sending an appropriate error notification message to the SCSI controller of the target operation at the connection destination when executing error processing, useless message exchange by sending unsupported messages Another object of the present invention is to provide a method for discriminating arbitrary message data that can delete the message and can simplify the process itself when an abnormality occurs.

[0017]

The arbitrary message data discriminating method of the present invention is applied to each SC connected on the SCSI bus.
In a system in which an SI controller individually supports arbitrary messages used in a message phase and transfers data by SCSI, a SCSI controller of a target operation connected to the same SCSI bus in a SCSI controller of an initiator operation The SC of each target operation is an arbitrary message group supported by the controller.
A message information storage register that stores the ID information of each SI controller, and ID information that sends the ID information of the SCSI controller of the target operation of the connection destination when the SCSI controller of the initiator operation is executing the operation of the SCSI bus. The management mechanism and the SCSI for the initiator operation based on the ID information sent from the ID information management mechanism.
Arbitrary message validating bit indicating that the controller is executing the operation of the SCSI bus and an arbitrary message judging unit for judging an arbitrary message group supported by the SCSI controller of the target operation connected on the same SCSI bus. And a support message storage register that stores the arbitrary message valid bit and the arbitrary message group determined by the arbitrary message determination unit, and the SCSI controller of the initiator operation is connected to the same SCSI bus. When sending an arbitrary message to the SCSI controller of the target operation, it is possible to always send an appropriate arbitrary message to the SCSI controller of the target operation of the connection destination.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the drawings.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing the configuration of an arbitrary message data discrimination system according to an embodiment of the present invention. In the arbitrary message data discriminating method of the present embodiment, the SCSI controller 2 of the initiator operation and the SCSI controllers 31, 32, ..., 3n (n is a positive integer) of the target operation are connected via the SCSI bus 1. Are connected together to form the main part.

Initiator operation SCSI controller 2
Is a target operation SC connected to the SCSI bus 1.
A message information storage register 21 capable of storing an arbitrary message group supported by the SI control devices 31, 32, ..., 3n for each ID information, and an SCS for the initiator operation.
When the I controller 2 is executing the operation of the SCSI bus 1, the ID information of the SCSI controller 3i (i is any integer from 1 to n) of the target operation of the connection destination with respect to the arbitrary message determination unit 23. ID information management mechanism 2 for sending
2 and the SCSI controller 2 operating the initiator based on the ID information from the ID information management mechanism 22
Message validating bit indicating that the operation is being performed and an arbitrary message determining unit 23 that determines an arbitrary message group supported by the SCSI control device 3i of the target operation of the connection destination, and an arbitrary message sent from the arbitrary message determining unit 23. A support message storage register 24 that stores a valid bit and an arbitrary message group, and a CPU (Central Process) as a control unit.
ng Unit) 25. Reference numeral 210 is a message information reception signal line, 220 is an ID information transmission signal line, 230 is a message information transmission signal line, and 240 is a local bus.

Referring to FIG. 2, the message information storage register 21 has an SCS for each ID information ID = 1, ..., N.
An arbitrary message group supported by the SCSI controllers 31, 32, ..., 3n for target operation connected to the I-bus 1 is stored and written by software at the time of initialization processing such as power-on. .

The ID information management mechanism 22 includes a first storage unit 221 for storing the ID information of the own SCSI control device 2 and a second storage unit 222 for storing the ID information of the SCSI control device 3i of the target operation of the connection destination. , The SCSI bus 1 is constantly monitored, and a bit corresponding to the ID information of the own SCSI control device 2 stored in the first storage unit 221 is set on the data line of the SCSI bus 1 in the selection / reselection phase. , ID of the SCSI controller 3i of the target operation of the connection destination that is simultaneously standing on the data line
Information is written in the second storage unit 222, and after the selection / reselection phase is completed, when the next phase is determined, it is determined that the own SCSI control device 2 is in the operation execution state of the SCSI bus 1, and the second storage unit 222 And a determination unit 223 that transmits the ID information stored in the optional message determination unit 23 via the ID information transmission signal line 220. When the SCSI controller 2 in the initiator operation is executing the operation of the SCSI bus 1, the ID information management mechanism 22 determines the ID information of the SCSI controller 3i in the target operation of the connection destination through the ID information transmission signal line 220 as an arbitrary message. On the other hand, when the SCSI control device 2 of the initiator operation is not executing the operation of the SCSI bus 1 while sending to the unit 23, the ID information of the SCSI control device 3i of the target operation of the connection destination is sent through the ID information sending signal line 220 It shall not be sent to 23.

When the ID information is sent from the ID information management mechanism 22, the arbitrary message judgment unit 23 judges that the SCSI controller 2 of the initiator operation is executing the operation on the SCSI bus 1, and the arbitrary message judgment unit 23 The valid bit is set to "1" indicating that the operation of the SCSI bus 1 is being executed. Also, an arbitrary message group supported by the SCSI controller 3i of the target operation of the connection destination corresponding to the ID information is received from the message information storage register 21 using the message information reception signal line 210, and the arbitrary message valid bit is received. And an arbitrary message group are sent to the support message storage register 24 through the message information sending signal line 230. If the ID information is not sent from the ID information management mechanism 22, the arbitrary message judgment unit 23 judges that the SCSI controller 2 of the initiator operation is not using the SCSI bus 1, and the arbitrary message judgment unit 23 The valid bit is set to "0" indicating that the operation of the SCSI bus 1 is not executed, and the support message storage register 2 is sent through the message information transmission signal line 230.
4

Referring to FIG. 3, the support message storage register 24 stores an arbitrary message valid bit indicating whether or not the SCSI controller 2 in the initiator operation is executing the operation of the SCSI bus 1. Part 241 and the SCS of the initiator operation
The I controller 2 includes an arbitrary message information section 242 in which an arbitrary message group supported by the SCSI controller 3i of the target operation of the connection destination while the operation of the SCSI bus 1 is being executed is stored. Here, if the arbitrary message valid bit portion 241 is "1", it can be determined that the operation of the SCSI bus 1 is being executed and the arbitrary message group stored in the arbitrary message information portion 241 is valid. Also, the arbitrary message valid bit part 241 is "0".
If so, it can be determined that the operation of the SCSI bus 1 is not being executed and the arbitrary message group stored in the arbitrary message information section 241 is invalid.

FIG. 4 shows the SCSI controller 2 for the initiator operation and the SCSI controller 3 for the target operation of the connection destination.
When information is transmitted / received to / from i, the SCSI controller 2 in the initiator operation detects a data parity error in the data phase, so a parity error occurs in the SCSI controller 3i in the target operation of the connection destination. INITI which is an optional message to notify that
It is a flowchart which shows the example of a process at the time of sending out an ATOR DETECTED ERROR message. Referring to FIG. 4, this process includes an arbitrary message information section validity determining step S101 and INITIATOR DETECT.
ED ERROR message support determination step S1
02 and the INITIATOR DETECTED ER
ROR message sending step S103 and ABORT
Message support determination step S104 and ABOR
It includes a T message sending step S105 and a RESET signal issuance processing transition step S106.

Next, the operation of the arbitrary message data discriminating method of this embodiment having the above-mentioned configuration will be described.

First, the SCSI controller 2 of the initiator operation confirms the arbitrary message valid bit portion 241 from the support message storage register 24. If the arbitrary message valid bit portion 241 is "0" indicating that the operation of the SCSI bus 1 is not executed, the SCS of the initiator operation
The I control device 2 determines that the arbitrary message group stored in the arbitrary message information unit 242 is invalid, and executes another abnormal process that does not involve the sending of the message indicating the abnormal notification.

In addition, in the SCSI controller 2 of the initiator operation, the arbitrary message valid bit part 241 is SCSI.
If "1" indicating that the operation of the bus 1 is being executed, it is determined that the arbitrary message group stored in the arbitrary message information unit 242 is valid, and the arbitrary message sent from the arbitrary message information unit 242 is the connection destination. Target operation SC
It is confirmed that the SI control device 3i is a support message. If the arbitrary message to be transmitted is the support message, the arbitrary message indicating the abnormality notification is transmitted to the SCSI control device 3i of the target operation of the connection destination. If the arbitrary message to be sent is not a support message, the SCSI controller 2 operating in the initiator operates another abnormal process without sending a message indicating an error notification to the SCSI controller 3i operating in the target operation of the connection destination. Is executed, or another arbitrary message indicating an abnormality notification supported by the SCSI controller 3i of the target operation of the connection destination is detected from the arbitrary message information part 242, and the SCSI controller 3i of the target operation of the connection destination detects it. It is also possible to notify the abnormality by sending another arbitrary message.

Here, the SCSI controller 2 of the initiator operation shown in FIG. 4 is the SCS of the target operation of the connection destination.
Since a certain error occurs while transmitting / receiving information to / from the I control device 3i, a specific message indicating the error notification is sent to the SCSI control device 3i of the target operation at the connection destination as an example. Explained.

Initiator operating SCSI controller 2
First, the arbitrary message valid bit portion 241 of the support message storage register 24 is confirmed (step S101). If "0" indicating that the SCSI bus 1 is not operating, a message indicating an abnormality notification is sent. The RESET signal issuance process is performed as another abnormal process (step S106). If the arbitrary message valid bit portion 241 is "1" indicating that the operation of the SCSI bus 1 is being executed, the SCSI controller 2 in the initiator operation determines that the arbitrary message information portion 242 is valid, and the arbitrary message valid portion 242 is valid. INITI in the bit part 241
It is confirmed whether the ATOR DETECTED ERROR message is stored as a support message (step S102).

If the INITIATOR DETECTED ERROR message is stored as a support message in the arbitrary message information section 242, the SCSI controller 2 operating as the initiator operates as an IN command to the SCSI controller 3i as the target operation of the connection destination.
An ITIATOR DETECTED ERROR message is sent to notify that a parity error has occurred (step S103).

In the optional message information section 242, I
If the NITIATOR DETECTED ERROR message is not stored as a support message, the SCSI controller 2 of the initiator operation is an ABORT message requesting stop of processing as another arbitrary message in the arbitrary message information part 242 indicating an abnormal notification It is confirmed whether or not is stored as (step S104).

Here, if the ABORT message is stored as a support message in the optional message information section 242, the SCSI controller 2 for the initiator operation.
Sends an ABORT message to the SCSI controller 32 of the target operation of the connection destination to request the stop of the processing (step S105).

In the optional message information section 242, A
If the BORT message is not stored as the support message, the SCSI controller 2 in the initiator operation stops the process by issuing the RESET signal (step S106).

As described above, the SCS of the initiator operation
When the I control device 2 sends an arbitrary message indicating an abnormality notification to the SCSI control device 3i of the target operation of the connection destination, the support message is always sent, thereby sending the unsupported message and the MESSA.
It is possible to delete useless message exchange due to the reception of the GE REJECT message, and to simplify the processing itself when an abnormality occurs.

[0036]

As described above, according to the present invention, the SCSI controller for the initiator operation is provided with the message information storage register, the ID information management mechanism, the arbitrary message judgment unit and the support message storage register in the initiator operation SCSI controller. When sending an arbitrary message indicating an error notification from the device to the SCSI controller of the target operation at the connection destination, the support message is always sent. Since it is not necessary to add the message reception process when the message in phase is indicated, unnecessary message exchange due to sending of unsupported messages can be deleted and the process itself when an error occurs can be simplified. Has the effect of becoming.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an arbitrary message data discrimination system according to an exemplary embodiment of the present invention.

FIG. 2 is a diagram showing the contents of a message information storage register in FIG.

FIG. 3 is a diagram showing the contents of a support message storage register in FIG.

FIG. 4 is a flowchart showing a processing example of a message transmission indicating an abnormality notification in the arbitrary message data discrimination method of the present embodiment.

FIG. 5 is a flowchart showing an example of a conventional message transmission process indicating an abnormality notification.

[Explanation of symbols]

1 SCSI bus 2 Initiator operation SCSI control device 21 Message information storage register 22 ID information management mechanism 23 Arbitrary message determination unit 24 Support message storage register 31, 32, ..., 3n Target operation SCSI control device 210 Message information reception signal line 220 ID information transmission signal line 221 First storage unit 222 Second storage unit 223 Judgment unit 230 Message information transmission signal line 241 Arbitrary message valid bit unit 242 Arbitrary message information unit

Claims (3)

[Claims] 1. Each SCSI connected on a SCSI bus
In a system in which a controller supports individual messages used in the message phase and transfers data by SCSI, the SCSI controller for the target operation connected to the same SCSI bus in the SCSI controller for the initiator operation A message information storage register that stores an arbitrary message group supported by the device for each ID information of the SCSI controller of each target operation, and a connection destination when the SCSI controller of the initiator operation is executing the operation of the SCSI bus. An ID information management mechanism for transmitting the ID information of the SCSI controller of the target operation, and that the SCSI controller of the initiator operation is executing the operation of the SCSI bus based on the ID information transmitted from this ID information management mechanism. Arbitrary message valid Bit and an arbitrary message judging section for judging an arbitrary message group supported by the SCSI controller of the target operation connected to the same SCSI bus, and the arbitrary message valid bit judged by this arbitrary message judging section, and A support message storage register for storing the arbitrary message group, wherein the SCSI controller operating the initiator operates in the same S
The S of the target operation connected on the CSI bus
A method for discriminating arbitrary message data, wherein when transmitting an arbitrary message to a CSI controller, an appropriate arbitrary message can always be transmitted to the SCSI controller of the target operation of the connection destination. 2. The ID information management mechanism includes a first storage unit that stores ID information of its own SCSI control device, a second storage unit that stores ID information of a SCSI control device of a target operation of a connection destination, and SCSI. Always monitor the bus and SCSI
2. The arbitrary message data discriminating method according to claim 1, further comprising a judging unit which sends out the ID information stored in the second storage unit when the control device recognizes that the SCSI bus has been acquired. 3. The support message storage register is used by the SCSI controller of the initiator operation to perform SCS.
The arbitrary message data discrimination according to claim 1, comprising an arbitrary message valid bit portion indicating whether or not the I bus is being operated, and an arbitrary message information portion for storing an arbitrary message group sent from the message information storage register. method.