Computer system and method of issuing input/output commands therefrom

• US 5,860,022 A
• Filed: 07/21/1995
• Issued: 01/12/1999
• Est. Priority Date: 07/26/1994
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Matsunaga, Kazuo, Kondou, Takeshi, Hirata, Toshiaki, Takada, Osamu
• Primary Examiner(s): Sheikh, Ayaz R.
• Assistant Examiner(s): WILEY, DAVID ARMAND
• Application Number:
  US08/505,144
• Time in Patent Office: 1,271 Days
• Field of Search: 395/821, 395/825, 395/309, 395/842, 395/287
• US Class Current: 710/1
• CPC Class Codes: G06F 13/126 and has means for transferring I/O instructions and statuses between control unit and main processor

Abstract

Disclosed herein is a computer system which comprises a plurality of input/output devices, an adapter device coupled to the plurality of input/output devices and a main processing unit for supplying an input/output request to each of the plurality of input/output devices through the adapter device. A plurality of input/output commands are respectively issued to the plurality of input/output devices from the main processing unit as one input/output start command. The adapter device specifies to which input/output devices the plurality of input/output commands included in the one input/output start command correspond. Further, the adapter device supplies input/output commands to the specified input/output devices respectively.

Claims

1. A computer system comprising a plurality of input/output devices;

an adapter device coupled to said plurality of input/output devices; and

a main processing unit coupled to said adapter device;

said main processing unit including means for transferring a plurality of input/output requests intended for respective ones of said plurality of input/output devices to said adapter device as a single input/output start command;

said adapter device including means for determining to which input/output devices said plurality of input/output requests included in said single input/output start command correspond, and means for supplying said plurality of input/output requests to said determined input/output devices, respectively.

2. A computer system comprising a plurality of input/output devices;

an adapter device coupled to said plurality of input/output devices; and

a main processing unit coupled to said adapter device;

said main processing unit including;

a wait request management table for storing therein and managing an input/output request intended for transfer to each of said plurality of input/output devices via said adapter device;

means for storing the input/output request in said wait request management table when the input/output request is immediately unprocessible upon transfer of the input/output request; and

means for creating a plurality of command sequences each comprised of input/output commands arranged in a row to be supplied to said each input/output device based on the input/output request stored in said wait request management table when the input/output request is processible, and for transferring said plurality of command sequences to said adapter device as a single input/output start command;

said adapter device including;

means for determining to which input/output devices said plurality of command sequences included in said single input/output start command correspond; and

means for supplying the input/output commands of each of said plurality of command sequences to said determined input/output devices, respectively.

3. A computer system according to claim 2, wherein said each input/output device includes a means for issuing an end interruption to said main processing unit when a process for a given input/output command is finished;

and

said main processing unit includes a means for judging whether the input/output request is processible when the end interruption for the input/output command is triggered, creating a plurality of command sequences each comprised of input/output commands arranged in a row to be supplied to said each input/output device, at each input/output device based on the input/output request stored in said wait request management table when it is judged that the input/output request is processible, and transferring the plurality of command sequences to said adapter device as one input/output start command.

4. A computer system according to claim 2, wherein the plurality of command sequences transferred to said adapter device from said main processing unit as the single input/output start command are managed by a table having a structure wherein blocks, each including address information for specifying a leading position of each command sequence and identifier information for determining a single input/output device corresponding to an object for executing each command in the command sequence, are respectively set as basic units, and wherein the plurality of blocks are continuously provided.

5. A computer system according to claim 4, wherein each of the blocks included in said table is provided with flag information indicative of whether said adapter device has captured a command sequence corresponding to a corresponding block, and when said main processing unit transfers the single input/output start command, the flag information is issued as ON, whereas when said adapter device takes in a command sequence included in the single input/output start command, the flag information is brought to OFF.

6. A computer system comprising a plurality of input/output devices;

an adapter device coupled to said plurality of input/output devices; and

a main processing unit coupled to said adapter device, said main processing unit having an application executing unit for executing an application program and a driver for processing an input/output request issued from the application executing unit;

said driver including means for producing an input/output command based on the input/output request issued from the application executing unit and transferring a plurality of said input/output commands to respective ones of said plurality of input/output devices as a single input/output start command;

said adapter device including means for determining to which input/output devices said plurality of input/output commands included in said single input/output start command correspond; and

means for supplying said plurality of input/output commands to said determined input/output devices, respectively.

7. A computer system according to claim 6, wherein said driver further includes means for supplying said plurality of input commands to said adapter device as said single input/output start command on a first out basis before acceptance of a data input request from the application executing unit.

8. A computer system according to claim 7, wherein said means for supplying the input commands to said adapter device on the first out basis includes:

first storing means for storing therein a first prescribed number indicative of the maximum number of input commands respectively issued to said input/output devices, second storing means for storing therein a second prescribed number for prescribing an opportunity for reissuing an input command sequence, and third storing means for recording therein the number of uncompleted input commands issued to said respective input/output devices;

said means for supplying the input commands to said adapter device on the first out basis being constructed such that an input command sequence obtained by linking input commands to each other by the first prescribed number is created at each input/output device so as to be issued to said adapter device after initialization of said driver, the number of the input commands issued to said individual input/output devices is recorded in said third storing means, the number of the uncompleted input commands stored in said third storing means is thereafter decremented by one each time an input command completion report is received from said each input/output device, and when the number of the uncompleted input commands transferred to said individual input/output devices reaches the second prescribed number, a difference between the number of the uncompleted input commands stored in said third storing means and the first prescribed number stored in said first storing means is calculated, and an input command sequence obtained by linking input commands to each other by the number corresponding to the difference is retransferred to said adapter device.

9. A computer system according to claim 6, wherein said each input/output device is a line control device;

said main processing unit includes a protocol processor for dividing data on a data transfer request issued from the application executing unit and for adding communication protocol control information to the heads of the divided individual output data to thereby create a plurality of divided packets; and

said driver produces a plurality of said input/output commands based on the plurality of divided packets when the number of the plurality of divided packets is not greater than a continuous transfer number corresponding to the number of packets continuously transferable without confirming a delivery issued from the opposite party at the present time, and transfers the plurality of produced input/output commands as said single input/output start command to thereby transfer the output data about the plurality of divided packets through one input/output operation.

10. A computer system according to claim 6, wherein said each input/output device is a line control device;

and

said main processing unit includes;

a protocol processor for dividing data about a data transfer request issued from the application executing unit, creating data management information blocks for pointing the divided output data, creating communication protocol control information to be logically added to the heads of the divided output data such that divided packets are logically composed of the communication protocol control information and the output data, and creating data management information blocks for pointing the communication protocol control information; and

a repacking processor for allowing said adapter device to compare an overhead necessary to process a command for transferring the communication protocol control information pointed by other data management information block outputted from said protocol processor with an overhead necessary to copy the output data pointed by said other data management information block outputted from said protocol processor onto an area continuously linked to the communication protocol control information, setting the communication protocol control information and the output data to a continuous area and creating a data management information block for pointing the area when the latter overhead is smaller than the former overhead, and delivering the created data management information block to said driver.

11. A computer system comprising a plurality of input/output devices;

an adapter device coupled to said plurality of input/output devices; and

a main processing unit coupled to said adapter device, said main processing unit having an application executing unit for executing an application program and a driver for processing an input/output request issued from the application executing unit;

said driver including;

a wait request management table for storing therein and managing the input/output request issued from the application executing unit;

means for storing the input/output request in said wait request management table when the input/output request is immediately unprocessible upon issuance of the input/output request from the application executing unit; and

means for creating a plurality of command sequences each comprised of input/output commands arranged in a row to be supplied to said each input/output device based on the input/output request stored in said wait request management table when the input/output request is processible, and for transferring said plurality of command sequences to said adapter device as a single input/output start command;

said adapter device including;

means for determining to which input/output devices said plurality of command sequences included in said single input/output start command correspond; and

means for supplying the input/output commands of each of said plurality of command sequences to said determined input/output devices, respectively.

12. A computer system according to claim 11, wherein said driver further includes means for supplying said plurality of input commands to said adapter device as said single input/output start command on a first out basis before acceptance of a data input request from the application executing unit.

13. A computer system according to claim 11, wherein said each input/output device is a line control device;

said main processing unit includes a protocol processor for dividing data on a data transfer request issued from the application executing unit and for adding communication protocol control information to the heads of the divided individual output data to thereby create a plurality of divided packets; and

said driver produces a plurality of said input/output commands based on the plurality of divided packets when the number of the plurality of divided packets is not greater than a continuous transfer number corresponding to the number of packets continuously transferable without confirming a delivery issued from the opposite party at the present time, and transfers the plurality of produced input/output commands as said single input/output start command to thereby transfer the output data about the plurality of divided packets through one input/output operation.

14. A computer system according to claim 11, wherein said each input/output device is a line control device;

and

said main processing unit includes;

a protocol processor for dividing data about a data transfer request issued from the application executing unit, creating data management information blocks for pointing the divided output data, creating communication protocol control information to be logically added to the heads of the divided output data such that divided packets are logically composed of the communication protocol control information and the output data, and creating data management information blocks for pointing the communication protocol control information; and

a repacking processor for allowing said adapter device to compare an overhead necessary to process a command for transferring the communication protocol control information pointed by other data management information block outputted from said protocol processor with an overhead necessary to copy the output data pointed by said other data management information block outputted from said protocol processor onto an area continuously linked to the communication protocol control information, setting the communication protocol control information and the output data to a continuous area and creating a data management information block for pointing the area when the latter overhead is smaller than the former overhead, and delivering the created data management information block to said driver.

15. A method of transferring a plurality of input/output commands from a computer system including a plurality of input/output devices, an adapter device coupled to said plurality of input/output devices, and a main processing unit coupled to said adapter device, comprising the steps of:

transferring the plurality of input/output requests intended for respective ones of said plurality of input/output devices from said main processing unit to said adapter device as a single input/output start command;

said adapter device determining to which input/output devices said plurality of input/output requests included in said single input/output start command correspond; and

said adapter device supplying said plurality of input/output requests to said determined input/output devices, respectively.

16. A method of transferring a plurality of input/output commands from a computer system including a plurality of input/output devices, an adapter device coupled to said plurality of input/output devices, and a main processing unit coupled to said adapter device, comprising the steps of:

said main processing unit storing therein and managing an input/output request intended for transfer to said each input/output device via said adapter device in a wait request management table when the input/output request is immediately unprocessible upon transfer of the input/output request to said each input/output device;

said main processing unit creating a plurality of command sequences each comprised of input/output commands arranged in a row to be supplied to said each input/output device based on the input/output request stored in said wait request management table when the input/output request is processible, and for transferring said plurality of command sequences to said adapter device as a single input/output start command;

said adapter device determining to which input/output devices said plurality of command sequences included in said single input/output start command correspond; and

said adapter device supplying the input/output commands of each of said plurality of command sequences to said determined input/output devices, respectively.

17. A method of transferring a plurality of input/output commands according to claim 16, further comprising the steps of:

said each input/output device issuing an end interruption to said main processing unit when a process for a given input/output command is finished; and

said main processing unit judging whether the input/output request is processible when the end interruption for the input/output command is triggered, creating a plurality of command sequences each comprised of input/output commands arranged in a row to be supplied to said each input/output device, at each input/output device based on the input/output request stored in said wait request management table when it is judged that the input/output request is processible, and issuing the plurality of command sequences to said adapter device as said single input/output start command.

18. A method of transferring a plurality of input/output commands from a computer system including a plurality of input/output devices, an adapter device coupled to said plurality of input/output devices, and a main processing unit coupled to said adapter device, said main processing unit having an application executing unit for executing an application program and a driver for processing an input/output request issued from the application executing unit, comprising the steps of:

transferring said plurality of input/output commands to respective ones of said plurality of input/output devices from said driver as a single input/output start command;

said adapter device determining to which input/output devices said plurality of input/output commands included in said one input/output start command correspond; and

supplying said plurality of input/output commands to said determined input/output devices, respectively.

19. A method of transferring a plurality of input/output commands according to claim 18, further comprising a step, executed by said driver, for supplying said plurality of input commands to said adapter device as said single input/output start command on a first out basis before acceptance of a data input request from the application executing unit.

20. A method of transferring a plurality of input/output commands according to claim 19, wherein said step for supplying the input commands to said adapter device on the first out basis includes:

a step for creating an input command sequence obtained by linking input commands to each other by a predetermined maximum number of transferred input commands at each input/output device after initialization of said driver, and transferring the created input command sequence to said adapter device;

a step for recording the number of the input commands issued to said each input/output device; and

a step for decrementing the number of the stored uncompleted input commands by one each time an input command completion report is received from said each input/output device, calculating a difference between the number of the stored uncompleted input commands and the maximum number of transferred input commands if the number of the uncompleted input commands transferred to said each input/output device is not greater than a predetermined number of input commands, and retransferring an input command sequence obtained by linking input commands to each other by the number corresponding to the difference, to said adapter device.

21. A method of transferring a plurality of input/output commands according to claim 18, further comprising the steps of:

a protocol processing step executed by said main processing unit, for dividing data on a data transfer request issued from the application executing unit and adding communication protocol control information to the heads of the divided individual output data to thereby create a plurality of divided packets; and

said driver producing a plurality of input/output commands based on the plurality of divided packets when the number of the plurality of divided packets is not greater than a continuous transfer number corresponding to the number of packets continuously transferable without confirming a delivery issued from the opposite party at the present time, and transferring the plurality of produced input/output commands as said single input/output start command to thereby transfer the output data about the plurality of divided packets through one input/output operation.

22. A method of transferring a plurality of input/output commands according to claim 18, further comprising the steps of:

a protocol processing step executed by said main processing unit, for dividing data about the data transfer request issued from the application executing unit, creating data management information blocks for pointing the divided output data, creating communication protocol control information to be logically added to the heads of the divided output data such that divided packets are logically composed of the communication protocol control information and the output data, and creating data management information blocks for pointing the communication protocol control information;

said main processing unit allowing said adapter device to compare an overhead necessary to process a command for transferring the communication protocol control information pointed by other data management information block outputted from said protocol processing step with an overhead necessary to copy the output data pointed by said other data management information block outputted from said protocol processing step onto an area continuously linked to the communication protocol control information, setting the communication protocol control information and the output data to a continuous area and creating a data management information block for pointing the area when the latter overhead is smaller than the former overhead, and delivering the created data management information block to said driver.

23. A method of transferring a plurality of input/output commands from a computer system including a plurality of input/output devices, an adapter device coupled to said plurality of input/output devices, and a main processing unit coupled to said adapter device, said main processing unit having an application executing unit for executing an application program and a driver for processing an input/output request issued from the application executing unit, comprising the steps of:

said driver storing therein and managing an input/output request issued from the application executing unit in a wait request management table when the input/output request is immediately unprocessible upon issuance of the input/output request from the application executing unit;

said driver creating a plurality of command sequences each comprised of input/output commands arranged in a row to be supplied to said each input/output device based on the input/output request stored in said wait request management table when the input/output request is processible, and for transferring said plurality of command sequences to said adapter device as a single input/output start command;

said adapter device determining to which input/output devices said plurality of command sequences included in said single input/output start command correspond; and

said adapter device supplying the input/output commands of each of said plurality of command sequences to said determined input/output devices, respectively.

24. A method of transferring a plurality of input/output commands according to claim 23, further comprising a step, executed by said driver, for supplying said plurality of input commands to said adapter device as said single input/output start command on a first out basis before acceptance of a data input request from the application executing unit.

25. A method of transferring a plurality of input/output commands according to claim 23, further comprising the steps of:

a protocol processing step executed by said main processing unit, for dividing data on a data transfer request issued from the application executing unit and adding communication protocol control information to the heads of the divided individual output data to thereby create a plurality of divided packets; and

said driver producing a plurality of input/output commands based on the plurality of divided packets when the number of the plurality of divided packets is not greater than a continuous transfer number corresponding to the number of packets continuously transferable without confirming a delivery issued from the opposite party at the present time, and transferring the plurality of produced input/output commands as said single input/output start command to thereby transfer the output data about the plurality of divided packets through one input/output operation.

26. A method of transferring a plurality of input/output commands according to claim 23, further comprising the steps of:

a protocol processing step executed by said main processing unit, for dividing data about the data transfer request issued from the application executing unit, creating data management information blocks for pointing the divided output data, creating communication protocol control information to be logically added to the heads of the divided output data such that divided packets are logically composed of the communication protocol control information and the output data, and creating data management information blocks for pointing the communication protocol control information;

said main processing unit allowing said adapter device to compare an overhead necessary to process a command for transferring the communication protocol control information pointed by other data management information block outputted from said protocol processing step with an overhead necessary to copy the output data pointed by said other data management information block outputted from said protocol processing step onto an area continuously linked to the communication protocol control information, setting the communication protocol control information and the output data to a continuous area and creating a data management information block for pointing the area when the latter overhead is smaller than the former overhead, and delivering the created data management information block to said driver.