1 /**
2 * Copyright (c) 2012, University of Konstanz, Distributed Systems Group All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
5 * following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of
6 * conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice,
7 * this list of conditions and the following disclaimer in the documentation and/or other materials provided with the
8 * distribution. * Neither the name of the University of Konstanz nor the names of its contributors may be used to
9 * endorse or promote products derived from this software without specific prior written permission.
10 *
11 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
12 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13 * DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
14 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
15 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
16 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
17 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
18 */
19 package org.jscsi.initiator.connection.state;
20
21
22 import java.util.LinkedList;
23 import java.util.Queue;
24
25 import org.jscsi.exception.InternetSCSIException;
26 import org.jscsi.initiator.connection.Connection;
27 import org.jscsi.parser.OperationCode;
28 import org.jscsi.parser.ProtocolDataUnit;
29 import org.jscsi.parser.data.DataOutParser;
30 import org.jscsi.parser.datasegment.IDataSegmentIterator;
31 import org.jscsi.parser.datasegment.IDataSegmentIterator.IDataSegmentChunk;
32 import org.jscsi.parser.datasegment.OperationalTextKey;
33
34
35 /**
36 * <h1>WriteSecondBurstState</h1>
37 * <p/>
38 * This state handles the second and all following Write Sending States, which sends at most <code>MaxBurstLength</code>
39 * bytes in each sequence.
40 *
41 * @author Volker Wildi
42 */
43 public final class WriteSecondBurstState extends AbstractState {
44
45 // --------------------------------------------------------------------------
46 // --------------------------------------------------------------------------
47
48 /** The chunk of the data segment to send as next. */
49 private final IDataSegmentIterator iterator;
50
51 /**
52 * The Target Transfer Tag, which is sent by the iSCSI Target within a Ready2Transfer PDU.
53 */
54 private final int targetTransferTag;
55
56 /**
57 * The desired data transfer length, which the iSCSI Target specified in the last Ready2Transfer message.
58 */
59 private final int desiredDataTransferLength;
60
61 /** The sequence number of this data package unit. */
62 private int dataSequenceNumber;
63
64 /** The start offset of the data to send. */
65 private int bufferOffset;
66
67 // --------------------------------------------------------------------------
68 // --------------------------------------------------------------------------
69
70 /**
71 * Constructor to create a <code>WriteSecondBurstState</code> instance, which sends the second and all following
72 * data sequences.
73 *
74 * @param initConnection This is the connection, which is used for the network transmission.
75 * @param initIterator The next chunk of the data to send.
76 * @param initTargetTransferTag The Target Transfer Tag to use.
77 * @param initDesiredDataTransferLength The desired data transfer length, which the iSCSI Target specified in the
78 * last Ready2Transfer message.
79 * @param initDataSequenceNumber The Data Sequence Number to use as next.
80 * @param initBufferOffset The start offset of the data to send.
81 */
82 public WriteSecondBurstState (final Connection initConnection, final IDataSegmentIterator initIterator, final int initTargetTransferTag, final int initDesiredDataTransferLength, final int initDataSequenceNumber, final int initBufferOffset) {
83
84 super(initConnection);
85 iterator = initIterator;
86 targetTransferTag = initTargetTransferTag;
87 if (LOGGER.isDebugEnabled()) {
88 LOGGER.debug("TTT set to " + targetTransferTag);
89 }
90 desiredDataTransferLength = initDesiredDataTransferLength;
91 // dataSequenceNumber = initDataSequenceNumber;//FIXME always starts at
92 // 0
93 dataSequenceNumber = 0;
94 bufferOffset = initBufferOffset;
95 }
96
97 // --------------------------------------------------------------------------
98 // --------------------------------------------------------------------------
99
100 /** {@inheritDoc} */
101 public final void execute () throws InternetSCSIException {
102
103 final Queue<ProtocolDataUnit> protocolDataUnits = new LinkedList<ProtocolDataUnit>();
104
105 ProtocolDataUnit protocolDataUnit;
106 DataOutParser dataOut;
107 IDataSegmentChunk dataSegmentChunk;
108 boolean finalFlag = false;
109 final int maxRecvDataSegmentLength = connection.getSettingAsInt(OperationalTextKey.MAX_RECV_DATA_SEGMENT_LENGTH);
110 int bytes2Transfer = Math.min(connection.getSettingAsInt(OperationalTextKey.MAX_BURST_LENGTH), desiredDataTransferLength);
111
112 if (LOGGER.isTraceEnabled()) {
113 LOGGER.trace("bytes2Transfer: " + bytes2Transfer + " iterator.hasNext(): " + iterator.hasNext());
114 }
115
116 while (bytes2Transfer > 0 && iterator.hasNext()) {
117 if (bytes2Transfer <= maxRecvDataSegmentLength) {
118 dataSegmentChunk = iterator.next(bytes2Transfer);
119 finalFlag = true;
120 } else {
121 dataSegmentChunk = iterator.next(maxRecvDataSegmentLength);
122 finalFlag = false;
123 }
124
125 protocolDataUnit = protocolDataUnitFactory.create(false, finalFlag, OperationCode.SCSI_DATA_OUT, connection.getSetting(OperationalTextKey.HEADER_DIGEST), connection.getSetting(OperationalTextKey.DATA_DIGEST));
126 protocolDataUnit.getBasicHeaderSegment().setInitiatorTaskTag(connection.getSession().getInitiatorTaskTag());
127
128 dataOut = (DataOutParser) protocolDataUnit.getBasicHeaderSegment().getParser();
129
130 dataOut.setTargetTransferTag(targetTransferTag);
131 dataOut.setDataSequenceNumber(dataSequenceNumber++);
132 dataOut.setBufferOffset(bufferOffset);
133 bufferOffset += maxRecvDataSegmentLength;
134
135 protocolDataUnit.setDataSegment(dataSegmentChunk);
136
137 protocolDataUnits.offer(protocolDataUnit);
138 bytes2Transfer -= maxRecvDataSegmentLength;
139 }
140
141 connection.send(protocolDataUnits);
142 connection.nextState(new WriteSecondResponseState(connection, iterator, dataSequenceNumber, bufferOffset));
143
144 // return true;
145 }
146
147 /**
148 * {@inheritDoc}
149 */
150 public boolean nextStateFollowing () {
151 return true;
152 }
153
154 // --------------------------------------------------------------------------
155 // --------------------------------------------------------------------------
156 // --------------------------------------------------------------------------
157 // --------------------------------------------------------------------------
158
159 }