Patent application number | Description | Published |
20090210559 | PROCESSING A VARIABLE LENGTH DEVICE COMMAND WORD AT A CONTROL UNIT IN AN I/O PROCESSING SYSTEM - A computer program product, apparatus and method for processing a variable length device command word (DCW) at a control unit configured for communication with an input/output (I/O) subsystem in an I/O processing system. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a DCW at the control unit from the I/O subsystem. The DCW specifies one or more I/O operations and includes a command, a control data count, and control data having a varying length specified by the control data count. The control data is extracted in response to the control data count. The command is then executed in response to the extracted control data to perform the specified one or more I/O operations. | 08-20-2009 |
20090210560 | CANCEL INSTRUCTION AND COMMAND FOR DETERMINING THE STATE OF AN I/O OPERATION - The state of an input/output (I/O) operation is determined in an I/O processing system. A command is received from an I/O operating system at a channel subsystem for initiating the I/O operation, a time period is for completion of the I/O operation, and the command for initiating the I/O operation is sent from the channel subsystem to the control unit. Responsive to the time period nearing elapsing without the I/O operation completing, a cancel instruction is received from the I/O operating system at the channel subsystem. Responsive to a determination by the I/O operating system to interrogate the control unit, an instruction to interrogate the control unit is received with the cancel instruction from the I/O operating system. | 08-20-2009 |
20090210561 | PROCESSING OF DATA TO PERFORM SYSTEM CHANGES IN AN INPUT/OUTPUT PROCESSING SYSTEM - A computer program product, an apparatus, and a method for processing communications between a target and an initiator an input/output processing system are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes: sending a message from the initiator to the target, the message requesting suspension of input/output operations between the initiator and the target for a period of time, the period of time being defined by the message; responsive to the message, suspending input/output operation messages for the period of time; performing a system change comprising at least one of: at least one update, a computer program installation, a recovery, and a change in operating parameters; and initiating new input/output operations after at least one of: expiration of the period of time and initiation of new input/output operations by the initiator. | 08-20-2009 |
20090210562 | PROCESSING COMMUNICATION DATA IN A SHIPS PASSING CONDITION - Articles of manufacture, apparatuses, and methods for processing communications between a control unit and a channel subsystem in an input/output processing system are disclosed. Embodiments of the invention include an article of manufacture including at least one computer usable medium having computer readable program code logic to processing communications between a control unit and a channel subsystem in an input/output processing system. The computer readable program code logic performs a method including: sending a message in a first mode from the control unit to the channel subsystem; receiving a command in a second mode from the channel subsystem at the control unit; determining whether the command is responsive to the message; and responsive to the command being not responsive to the message, determining whether to perform one of i) executing the command and ii) terminating the command. | 08-20-2009 |
20090210563 | PROVIDING INDIRECT DATA ADDRESSING FOR A CONTROL BLOCK AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An computer program product, apparatus, and method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes the host computer system obtaining a transport command word (TCW) for an I/O operation. The TCW specifies a location of one or more I/O commands and a flag. The flag is set to indicate that the location is an indirect address. The host computer system extracts the location of the one or more I/O commands and the flag from the TCW. The host computer system gathers the one or more I/O commands responsive to the location specified by the TCW and the flag, and then forwards the one or more I/O commands to the control unit for execution. | 08-20-2009 |
20090210564 | PROCESSING OF DATA TO SUSPEND OPERATIONS IN AN INPUT/OUTPUT PROCESSING SYSTEM - A computer program product, an apparatus, and a method for processing communications between a target and an initiator an input/output processing system are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes: sending a message between the initiator and the target, the message requesting suspension of input/output operations between the initiator and the target for a period of time, the period of time being defined by the message; and responsive to the message, suspending input/output operation messages for the period of time. | 08-20-2009 |
20090210570 | EXTENDED MEASUREMENT WORD DETERMINATION AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An article of manufacture, an apparatus, and a method for determining an extended measurement word at a channel subsystem of an I/O processing system using data from a control unit are provided. The article of manufacture includes at least one computer usable medium having computer readable program code logic. The computer readable program code logic performs a method including sending a command message to the control unit, and receiving a transport response information unit message at the channel subsystem in response to sending the command message to the control unit. The computer readable program code logic additionally extracts a plurality of time values from the transport response information unit message as calculated by the control unit, calculates an extended measurement word as a function of the time values, and writes the extended measurement word to computer readable memory in the I/O processing system. | 08-20-2009 |
20090210571 | PROCESSING OF DATA TO MONITOR INPUT/OUTPUT OPERATIONS - A computer program product, an apparatus, and a method for processing communications between a control unit and a channel subsystem in an input/output processing system are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes: sending a command from the channel subsystem to the control unit to initiate an input/output operation; setting a time period for completion of the operation; and responsive to the operation not completing within the time period, sending a message to determine whether the control unit has an exchange open for the command. | 08-20-2009 |
20090210572 | COMPUTER COMMAND AND RESPONSE FOR DETERMINING THE STATE OF AN I/O OPERATION - A computer program product, apparatus, and method are provided for determining a state of an input/output (I/O) operation in an I/O processing system. A request from a channel subsystem is received at a control unit for performing the I/O operation. After a predetermined amount of time passes without the I/O operation completing, an interrogation request is received from the channel subsystem at the control unit for determining the state of the I/O operation. A response is sent from the control unit to the channel subsystem indicating the state of the I/O operation in response to the interrogation request. The response also includes information regarding a state of an I/O device executing the I/O operation and information indicating a state of the control unit controlling the I/O device executing the I/O operation. | 08-20-2009 |
20090210573 | COMPUTER COMMAND AND RESPONSE FOR DETERMINING THE STATE OF AN I/O OPERATION - A state of an input/output (I/O) operation in an I/O processing system is determined. A request for performing the I/O operation is received from an I/O operating system at a channel subsystem and forwarded to a control unit controlling an I/O device for executing the I/O operation. After a predetermined amount of time passes without receiving indication from the control unit that the I/O operation is completed, an interrogation request is received at the channel subsystem from the I/O operating system for determining the state of the I/O operation. An interrogation command is sent from the channel subsystem to the control unit. A response is received from the control unit, the response indicates a state of the I/O device executing the I/O operation, a state of the control unit controlling the I/O device executing the I/O operation, and the state of the I/O operation being executed. | 08-20-2009 |
20090210576 | PROVIDING INDIRECT DATA ADDRESSING IN AN INPUT/OUTPUT PROCESSING SYSTEM WHERE THE INDIRECT DATA ADDRESS LIST IS NON-CONTIGUOUS - Systems, methods and computer program products for providing indirect data addressing at an I/O subsystem of an I/O processing system. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a control word for an I/O operation. The control word includes an indirect data address for data associated with the I/O operation. The indirect data address includes a starting location of a list of storage addresses that collectively specify the data, the list spans two or more non-contiguous storage locations. Data is gathered responsive to the list. The gathered data is transmitted to a control unit in the I/O processing system. | 08-20-2009 |
20090210579 | OPEN EXCHANGE LIMITING IN AN I/O PROCESSING SYSTEM - A computer program product, an apparatus, and a method for limiting a number of open exchanges at a channel subsystem of an I/O processing system using data from a control unit. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method that includes sending a command message to the control unit, and receiving a transport response information unit message in response. The method further includes extracting a maximum control unit exchange parameter from the transport response information unit message, and determining a limit value for a maximum number of open exchanges between the channel subsystem and the control unit as a function of the extracted maximum control unit exchange parameter. The method additionally includes applying the limit value to prevent opening of a new exchange. | 08-20-2009 |
20090210580 | EARLY TERMINATION OF AN I/O OPERATION IN AN I/O PROCESSING SYSTEM - A computer program product, apparatus, and method for handling early termination of an I/O operation at a channel subsystem in an I/O processing system are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a request to terminate an I/O operation, and transmitting an abort command to a control unit in communication with the channel subsystem in response to receiving the request to terminate the I/O operation. The method also includes transmitting a purge path command to purge a path associated with the I/O operation, where the purge path command includes an error code identifying the request to terminate the I/O operation. | 08-20-2009 |
20090210581 | BI-DIRECTIONAL DATA TRANSFER WITHIN A SINGLE I/O OPERATION - An article of manufacture, apparatus, and a method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The method includes the host computer system obtaining a transport command word (TCW) for an I/O operation having both input and output data. The TCW specifies a location of the output data and a location for storing the input data. The host computer system forwards the I/O operation to the control unit for execution. The host computer system gathers the output data responsive to the location of the output data specified by the TCW, and then forwards the output data to the control unit for use in the execution of the I/O operation. The host computer system receives the input data from the control unit and stores the input data at the location specified by the TCW. | 08-20-2009 |
20090210582 | PROVIDING EXTENDED MEASUREMENT DATA IN AN I/O PROCESSING SYSTEM - An article of manufacture, an apparatus, and a method for providing extended measurement word data from a control unit to a channel subsystem of an I/O processing system are disclosed. The article of manufacture includes at least one computer usable medium having computer readable program code logic. The computer readable program code logic performs a method including receiving a command message from the channel subsystem at the control unit, and initiating a timing calculation sequence of a plurality of time values in response to receiving the command message at the control unit. The computer readable program code logic also populates extended measurement word data at the control unit including the plurality of time values, and outputs the extended measurement word data from the control unit to the channel subsystem. | 08-20-2009 |
20090210583 | RESERVED DEVICE ACCESS CONTENTION REDUCTION - A computer program product, an apparatus, and a method for reducing reserved device access contention at a control unit in communication with a plurality of operating systems via one or more channels are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method that includes receiving a command message at the control unit from a first operating system, including an I/O operation command for a device. A device busy indicator is received, indicating that a second operating system has reserved the device. The command message is queued on a device busy queue in response to the device busy indicator. The control unit monitors for a device end indicator. The device busy queue is serviced to perform the I/O operation command in response to the device end indicator. | 08-20-2009 |
20090210584 | EXCEPTION CONDITION DETERMINATION AT A CONTROL UNIT IN AN I/O PROCESSING SYSTEM - A computer program product, apparatus, and method for providing exception condition feedback at a control unit to a channel subsystem in an I/O processing system are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a command message at the control unit from the channel subsystem, and detecting an exception condition in response to unsuccessful execution of at least one command in the command message. The method further includes identifying a termination reason code associated with the exception condition, writing the termination reason code to a response message, and sending the response message to the channel subsystem. | 08-20-2009 |
20090210585 | PROCESSING OF DATA TO SUSPEND OPERATIONS IN AN INPUT/OUTPUT PROCESSING LOG-OUT SYSTEM - A computer program product, an apparatus, and a method for processing communications between a control unit and a channel subsystem in an input/output processing system are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes: sending a Process Log-out (PRLO) message from the control unit to the channel subsystem, the message requesting suspension of input/output operations between the control unit and the channel subsystem for a period of time, the period of time being defined by the PRLO message; responsive to the PRLO message, suspending by the channel all input/output operation messages for the period of time, wherein suspending comprises stopping input/output operation messages during the period of time; and responsive to an expiration of the period of time, sending a Process Log-in (PRLI) message from the channel subsystem to the control unit to re-initiate an operating environment between the channel subsystem and the control unit. | 08-20-2009 |
20090210768 | EXCEPTION CONDITION HANDLING AT A CHANNEL SUBSYSTEM IN AN I/O PROCESSING SYSTEM - A computer program product, apparatus, and method for handling exception condition feedback at a channel subsystem of an I/O processing system using data from a control unit are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes sending a command message to the control unit, and receiving a response message in response to the command message. The response message includes exception condition feedback identifying a termination reason code in response to unsuccessful execution of at least one command in the command message. The method also includes interrupting a CPU in the I/O processing system, and reporting status associated with the exception condition feedback to the CPU in an interrupt response block. | 08-20-2009 |
20090210769 | MULTIPLE CRC INSERTION IN AN OUTPUT DATA STREAM - A computer program product, apparatus, and method for inserting multiple CRCs in an output data stream from a channel subsystem to a control unit are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a message to transmit from the channel subsystem to the control unit. The method also includes determining a first CRC insertion position, and receiving a first CRC calculated over a first block of data in the message. The method additionally includes inserting the first calculated CRC at the first CRC insertion position, and determining a second CRC insertion position. The method further includes receiving a second CRC calculated over a second block of data in the message, and inserting the second calculated CRC at the second CRC insertion position. | 08-20-2009 |
20090210884 | PROCESSING OF DATA TO DETERMINE COMPATABILITY IN AN INPUT/OUTPUT PROCESSING SYSTEM - A computer program product, an apparatus, and a method for processing communications between a control unit and a channel subsystem in an input/output processing system are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method including: sending a message from the channel subsystem to the control unit in a first mode; receiving a response from the control unit and determining from the response whether the control unit supports a message protocol; and responsive to the message protocol being supported by the control unit, sending another message using the message protocol from the channel subsystem to the control unit to determine whether the control unit supports a second mode. | 08-20-2009 |
20110131343 | PROVIDING INDIRECT DATA ADDRESSING IN AN INPUT/OUTPUT PROCESSING SYSTEM WHERE THE INDIRECT DATA ADDRESS LIST IS NON-CONTIGUOUS - Systems, methods and computer program products for providing indirect data addressing at an I/O subsystem of an I/O processing system. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a control word for an I/O operation. The control word includes an indirect data address for data associated with the I/O operation. The indirect data address includes a starting location of a list of storage addresses that collectively specify the data, the list spans two or more non-contiguous storage locations. Data is gathered responsive to the list. The gathered data is transmitted to a control unit in the I/O processing system. | 06-02-2011 |
20110196993 | BI-DIRECTIONAL DATA TRANSFER WITHIN A SINGLE I/O OPERATION - An article of manufacture, apparatus, and a method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The method includes the host computer system obtaining a transport command word (TCW) for an I/O operation having both input and output data. The TCW specifies a location of the output data and a location for storing the input data. The host computer system forwards the I/O operation to the control unit for execution. The host computer system gathers the output data responsive to the location of the output data specified by the TCW, and then forwards the output data to the control unit for use in the execution of the I/O operation. The host computer system receives the input data from the control unit and stores the input data at the location specified by the TCW. | 08-11-2011 |
20120117275 | PROVIDING INDIRECT DATA ADDRESSING FOR A CONTROL BLOCK AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An computer program product, apparatus, and method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes the host computer system obtaining a transport command word (TCW) for an I/O operation. The TCW specifies a location of one or more I/O commands and a flag set to indicate that the location is an indirect address. The host computer system extracts the location of the one or more I/O commands and the flag from the TCW, gathers the one or more I/O commands responsive to the location specified by the TCW and the flag, and then forwards the one or more I/O commands to the control unit for execution. | 05-10-2012 |
20130179596 | PROVIDING INDIRECT DATA ADDRESSING IN AN INPUT/OUTPUT PROCESSING SYSTEM WHERE THE INDIRECT DATA ADDRESS LIST IS NON-CONTIGUOUS - A method includes configuring a processing circuit to perform: receiving a control word for an I/O operation, forwarding a transport command control block (TCCB) from the channel subsystem to a control unit, gathering data associated with the I/O operation, and transmitting the gathered data to the control unit in the I/O processing system. Gathering the data includes accessing entries of a list of storage addresses that collectively specifying the data. Based on an entry of the list comprising a not-set first flag and a corresponding first storage address, gathering data from a corresponding storage location, and based on an entry of the list comprising a set first flag and a corresponding second storage address, obtaining a next entry of the list from a second storage location. | 07-11-2013 |
20130282929 | BI-DIRECTIONAL DATA TRANSFER WITHIN A SINGLE I/O OPERATION - A computer program product, apparatus, and a method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The method includes receiving a command block from the channel subsystem, the command block including at least one input command and at least one output command specified by a transport command word (TCW) and associated with the I/O operation, the I/O operation having both input and output data, the TCW specifying a location in the memory of the output data and a location in the memory for storing the input data; receiving the output data specified by the TCW and executing the at least one output command; and forwarding the input data specified by the TCW to the channel subsystem for storage at a location specified by the TCW. | 10-24-2013 |
20130304940 | PROVIDING INDIRECT DATA ADDRESSING FOR A CONTROL BLOCK AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An computer program product, apparatus, and method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The computer program product is provided for performing a method including: obtaining a transport command word (TCW) for an I/O operation, the TCW specifying a location address and indicating whether the TCW directly or indirectly addresses a message for transmitting one or more commands to the control unit; extracting the specified location address from the TCW; obtaining the message from the specified location address based on the TCW indicating direct addressing, the message including one or more I/O commands; gathering one or more I/O commands from command locations specified by a list of addresses identified by the specified location address to form the message based on the TCW indicating indirect addressing; and forwarding the message to the control unit for execution. | 11-14-2013 |
20140297891 | PROVIDING INDIRECT DATA ADDRESSING FOR A CONTROL BLOCK AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An computer program product, apparatus, and method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The computer program product is provided for performing a method including: sending a transport command word (TCW) to an I/O subsystem, the TCW specifying a location address and indicating whether the TCW directly or indirectly addresses a message; extracting the location address from the TCW; obtaining the message from the specified location address based on the TCW indicating direct addressing, the message including the one or more I/O commands; gathering the one or more I/O commands from command locations specified by a list of addresses identified by the specified location address to form the message based on the TCW indicating indirect addressing; and generating a message including the one or more I/O commands. | 10-02-2014 |
20140379948 | PROVIDING INDIRECT DATA ADDRESSING IN AN INPUT/OUTPUT PROCESSING SYSTEM WHERE THE INDIRECT DATA ADDRESS LIST IS NON-CONTIGUOUS - A computer program product for processing input/output (I/O) data is provided for performing a method, which includes receiving a control word having an indirect data address including a starting location of a list of storage addresses, gathering the data and transmitting gathered data to a control unit in the I/O processing system. Gathering includes accessing an entry of the list, the entry located at an entry storage location and including an address. Based on the entry of the list indicating that the address is a data address, data is gathered from a data storage location, and a next entry of the list is accessed. Based on the entry of the list indicating that the address is an address of a next entry of the list, the next entry of the list is obtained from another storage location that is located non-contiguously to the entry storage location. | 12-25-2014 |
20150074295 | BI-DIRECTIONAL DATA TRANSFER WITHIN A SINGLE I/O OPERATION - A computer program product, apparatus, and a method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The method includes receiving, by a control unit, a command block configured to hold a plurality of commands including an input command and/or an output command, the plurality of commands specified by a transport command word (TCW) including a read indicator configured to indicate whether the I/O operation includes input data and a write indictor configured to indicate whether the I/O operation includes output data; based on the command block holding at least one output command, receiving the output data and executing the at least one output command; and based on the command block holding at least one input command, forwarding the input data to the channel subsystem for storage at a location specified by the TCW. | 03-12-2015 |