org.jscsi.parser.tmf

Class TaskManagementFunctionResponseParser

java.lang.Object

org.jscsi.parser.AbstractMessageParser

org.jscsi.parser.TargetMessageParser

org.jscsi.parser.tmf.TaskManagementFunctionResponseParser

public final class TaskManagementFunctionResponseParser
extends TargetMessageParser

This class parses a Task Management Function Response message defined in the iSCSI Standard (RFC3720).

Task Management Actions on Task Sets

The execution of ABORT TASK SET and CLEAR TASK SET Task Management function requests consists of the following sequence of events in the specified order on each of the entities.

The initiator:

1. Issues ABORT TASK SET/CLEAR TASK SET request.
2. Continues to respond to each target transfer tag received for the affected task set.
3. Receives any responses for the tasks in the affected task set (may process them as usual because they are guaranteed to be valid).
4. Receives the task set management response, thus concluding all the tasks in the affected task set.

The target:

1. Receives the ABORT TASK SET/CLEAR TASK SET request.
2. Waits for all target transfer tags to be responded to and for all affected tasks in the task set to be received.
3. Propagates the command to and receives the response from the target SCSI layer.
4. Takes note of last-sent StatSN on each of the connections in the iSCSI sessions (one or more) sharing the affected task set, and waits for acknowledgement of each StatSN (may solicit for acknowledgement by way of a NOP-In). If some tasks originate from non-iSCSI I_T_L nexi then the means by which the target insures that all affected tasks have returned their status to the initiator are defined by the specific protocol.
5. Sends the task set management response to the issuing initiator.

TotalAHSLength and DataSegmentLength

For this PDU TotalAHSLength and DataSegmentLength MUST be 0.

Author:

Volker Wildi

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TaskManagementFunctionResponseParser.ResponseCode This enumeration defines all valid response code, which are defined in the iSCSI Standard (RFC 3720).

Field Summary

Fields inherited from class org.jscsi.parser.TargetMessageParser

expectedCommandSequenceNumber, maximumCommandSequenceNumber, statusSequenceNumber

Fields inherited from class org.jscsi.parser.AbstractMessageParser

logicalUnitNumber, protocolDataUnit

Constructor Summary

Constructors

Constructor and Description
TaskManagementFunctionResponseParser(ProtocolDataUnit initProtocolDataUnit) Default constructor, creates a new, empty TaskManagementFunctionResponseParser object.

Method Summary

Methods

Modifier and Type	Method and Description
protected void	checkIntegrity() This method checks, if all parsed fields are valid.
void	clear() This method sets all settings to their initial values.
protected void	deserializeBytes1to3(int line) Parse the bytes 1 till 3 in the Basic Header Segment.
protected void	deserializeBytes20to23(int line) Parse the bytes 20 till 23 in the Basic Header Segment.
DataSegmentFactory.DataSegmentFormat	getDataSegmentFormat() If this method returns true, hen it indicates that the data segment data is interpreted as binary data.
TaskManagementFunctionResponseParser.ResponseCode	getResponse() The target provides a Response, which may take on the following values: Response Code Description 0 Function complete. 1 Task does not exist. 2 LUN does not exist. 3 Task still allegiant. 4 Task allegiance reassignment not supported. 5 Task management function not supported. 6 Function authorization failed. 255 Function rejected. All other values are reserved. protected int serializeBytes1to3() Serializes the bytes 1 till 3 in the Basic Header Segment. String toString() This method concatenate all the fields of a derived parser to allow an easy generation of debug informations. Methods inherited from class org.jscsi.parser.TargetMessageParser deserializeBytes24to27, deserializeBytes28to31, deserializeBytes32to35, deserializeBytes36to39, deserializeBytes40to43, deserializeBytes44to47, getExpectedCommandSequenceNumber, getMaximumCommandSequenceNumber, getShortInfo, getStatusSequenceNumber, incrementSequenceNumber, serializeBytes20to23, serializeBytes24to27, serializeBytes28to31, serializeBytes32to35, serializeBytes36to39, serializeBytes40to43, serializeBytes44to47, setExpectedCommandSequenceNumber, setMaximumCommandSequenceNumber, setStatusSequenceNumber Methods inherited from class org.jscsi.parser.AbstractMessageParser canContainAdditionalHeaderSegments, canHaveDigests, deserializeBytes12to15, deserializeBytes8to11, getLogicalUnitNumber, serializeBytes12to15, serializeBytes8to11, setLogicalUnitNumber Methods inherited from class java.lang.Object clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait Constructor Detail TaskManagementFunctionResponseParser public TaskManagementFunctionResponseParser(ProtocolDataUnit initProtocolDataUnit) Default constructor, creates a new, empty TaskManagementFunctionResponseParser object. Parameters: initProtocolDataUnit - The reference ProtocolDataUnit instance, which contains this TaskManagementFunctionResponseParser subclass object. Method Detail toString public final String toString() This method concatenate all the fields of a derived parser to allow an easy generation of debug informations. Overrides: toString in class TargetMessageParser Returns: The debug formatted string. getDataSegmentFormat public final DataSegmentFactory.DataSegmentFormat getDataSegmentFormat() If this method returns true, hen it indicates that the data segment data is interpreted as binary data. Else the data segment data must be interpreted as Text Format. Specified by: getDataSegmentFormat in class AbstractMessageParser Returns: Returns a format defined by the DataSegmentFormat enumeration. See Also: DataSegmentFactory.DataSegmentFormat clear public final void clear() This method sets all settings to their initial values. Overrides: clear in class TargetMessageParser getResponse public final TaskManagementFunctionResponseParser.ResponseCode getResponse() The target provides a Response, which may take on the following values: Response Code Description 0 Function complete. 1 Task does not exist. 2 LUN does not exist. 3 Task still allegiant. 4 Task allegiance reassignment not supported. 5 Task management function not supported. 6 Function authorization failed. 255 Function rejected. All other values are reserved. For a discussion on usage of response codes 3 and 4, see Section 6.2.2 Allegiance Reassignment. For the TARGET COLD RESET and TARGET WARM RESET functions, the target cancels all pending operations across all Logical Units known to the issuing initiator. For the TARGET COLD RESET function, the target MUST then close all of its TCP connections to all initiators (terminates all sessions). The mapping of the response code into a SCSI service response code value, if needed, is outside the scope of this document. However, in symbolic terms Response values 0 and 1 map to the SCSI service response of FUNCTION COMPLETE. All other Response values map to the SCSI service response of FUNCTION REJECTED. If a Task Management function response PDU does not arrive before the session is terminated, the SCSI service response is SERVICE DELIVERY OR TARGET FAILURE. The response to ABORT TASK SET and CLEAR TASK SET MUST only be issued by the target after all of the commands affected have been received by the target, the corresponding task management functions have been executed by the SCSI target, and the delivery of all responses delivered until the task management function completion have been confirmed (acknowledged through ExpStatSN) by the initiator on all connections of this session. For the exact timeline of events, refer to Section 10.6.2 Task Management Actions on Task Sets. For the ABORT TASK function, If the Referenced Task Tag identifies a valid task leading to a successful termination, then targets must return the "Function complete" response. If the Referenced Task Tag does not identify an existing task, but if the CmdSN indicated by the RefCmdSN field in the Task Management function request is within the valid CmdSN window and less than the CmdSN of the Task Management function request itself, then targets must consider the CmdSN received and return the "Function complete" response. If the Referenced Task Tag does not identify an existing task and if the CmdSN indicated by the RefCmdSN field in the Task Management function request is outside the valid CmdSN window, then targets must return the "Task does not exist" response. Returns: The response code of this TaskManagementFunctionResponseParser object. deserializeBytes1to3 protected final void deserializeBytes1to3(int line) throws InternetSCSIException Parse the bytes 1 till 3 in the Basic Header Segment. Overrides: deserializeBytes1to3 in class TargetMessageParser Parameters: line - The actual line Throws: InternetSCSIException - If any violation of the iSCSI-Standard emerge. deserializeBytes20to23 protected final void deserializeBytes20to23(int line) throws InternetSCSIException Parse the bytes 20 till 23 in the Basic Header Segment. Overrides: deserializeBytes20to23 in class TargetMessageParser Parameters: line - The actual line Throws: InternetSCSIException - If any violation of the iSCSI-Standard emerge. checkIntegrity protected final void checkIntegrity() throws InternetSCSIException This method checks, if all parsed fields are valid. Because there are several fields, which are reserved for future versions, and these must be zero. Is this the case an exception will be thrown. Specified by: checkIntegrity in class AbstractMessageParser Throws: InternetSCSIException - If the integrity is violated. serializeBytes1to3 protected final int serializeBytes1to3() Serializes the bytes 1 till 3 in the Basic Header Segment. Overrides: serializeBytes1to3 in class TargetMessageParser Returns: The serialized byte representation. Overview Package Class Use Tree Deprecated Index Help Prev Class Next Class Frames No Frames All Classes Summary: Nested | Field | Constr | Method Detail: Field | Constr | Method Copyright © 2013 University of Konstanz, Distributed Systems Group. All Rights Reserved.