1 package org.jscsi.target.scsi.cdb;
2
3
4 import java.nio.ByteBuffer;
5
6 import org.jscsi.target.util.ReadWrite;
7
8
9 /**
10 * This class represents Command Descriptor Blocks for the <code>REPORT LUNS</code> SCSI command.
11 *
12 * @author Andreas Ergenzinger
13 */
14 public class ReportLunsCDB extends CommandDescriptorBlock {
15
16 /**
17 * The SELECT REPORT field specifies the types of logical unit addresses that shall be reported.
18 *
19 * @see SelectReport
20 */
21 private final SelectReport selectReport;
22
23 /**
24 * The ALLOCATION LENGTH field specifies the maximum number of bytes that an application client has allocated in the
25 * Data-In Buffer. An allocation length of zero specifies that no data shall be transferred. This condition shall
26 * not be considered as an error. The device server shall terminate transfers to the Data-In Buffer when the number
27 * of bytes specified by the ALLOCATION LENGTH field have been transferred or when all available data have been
28 * transferred, whichever is less.
29 * <p>
30 * The allocation length is used to limit the maximum amount of variable length data (e.g., mode data, log data,
31 * diagnostic data) returned to an application client. If the information being transferred to the Data-In Buffer
32 * includes fields containing counts of the number of bytes in some or all of the data, then the contents of these
33 * fields shall not be altered to reflect the truncation, if any, that results from an insufficient ALLOCATION
34 * LENGTH value, unless the standard that describes the Data-In Buffer format states otherwise.
35 * <p>
36 * If the amount of information to be transferred exceeds the maximum value that the ALLOCATION LENGTH field is
37 * capable of specifying, the device server shall transfer no data and terminate the command with CHECK CONDITION
38 * status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
39 * <p>
40 * If EVPD is set to zero, the allocation length should be at least five, so that the ADDITIONAL LENGTH field in the
41 * parameter data is returned. If EVPD is set to one, the allocation length should be should be at least four, so
42 * that the PAGE LENGTH field in the parameter data is returned.
43 */
44 private final int allocationLength;
45
46 public ReportLunsCDB (ByteBuffer buffer) {
47 super(buffer);
48
49 // select report
50 selectReport = SelectReport.getValue(buffer.get(2));
51 if (selectReport == null) addIllegalFieldPointer(2);// reserved select report value
52
53 // allocation length
54 allocationLength = ReadWrite.readFourByteInt(buffer, 6);
55 if (allocationLength < 16) addIllegalFieldPointer(6);// The allocation length should be at
56 // least 16.
57 }
58
59 public final int getAllocationLength () {
60 return allocationLength;
61 }
62
63 public final SelectReport getSelectReport () {
64 return selectReport;
65 }
66 }