1、American National StandardDeveloped byfor Information Technology SCSI Architecture Model - 4SAM-4INCITS 447-2008INCITS 447-2008Copyright American National Standards Institute Provided by IHS under license with ANSI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Co
2、pyright American National Standards Institute Provided by IHS under license with ANSI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-INCITS 447-2008American National Standardfor Information Technology SCSI Architecture Model - 4(SAM-4)SecretariatInformation Techno
3、logy Industry CouncilApproved November 14, 2008American National Standards Institute, Inc.AbstractThis standard specifies the SCSI Architecture Model. The purpose of the architecture is to provide a common basis for the coordination of SCSI standards and to specify those aspects of SCSI I/O system b
4、ehavior that are independent of a particular technology and common to all implementations.Copyright American National Standards Institute Provided by IHS under license with ANSI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Approval of an American National Standa
5、rd requires review by ANSI that therequirements for due process, consensus, and other criteria for approval havebeen met by the standards developer.Consensus is established when, in the judgement of the ANSI Board ofStandards Review, substantial agreement has been reached by directly andmaterially a
6、ffected interests. Substantial agreement means much more thana simple majority, but not necessarily unanimity. Consensus requires that allviews and objections be considered, and that a concerted effort be madetowards their resolution.The use of American National Standards is completely voluntary; th
7、eirexistence does not in any respect preclude anyone, whether he has approvedthe standards or not, from manufacturing, marketing, purchasing, or usingproducts, processes, or procedures not conforming to the standards.The American National Standards Institute does not develop standards andwill in no
8、circumstances give an interpretation of any American NationalStandard. Moreover, no person shall have the right or authority to issue aninterpretation of an American National Standard in the name of the AmericanNational Standards Institute. Requests for interpretations should beaddressed to the secr
9、etariat or sponsor whose name appears on the titlepage of this standard.CAUTION NOTICE: This American National Standard may be revised orwithdrawn at any time. The procedures of the American National StandardsInstitute require that action be taken periodically to reaffirm, revise, orwithdraw this st
10、andard. Purchasers of American National Standards mayreceive current information on all standards by calling or writing the AmericanNational Standards Institute.American National StandardPublished byAmerican National Standards Institute, Inc.25 West 43rd Street, New York, NY 10036Copyright 2008 by I
11、nformation Technology Industry Council (ITI)All rights reserved.No part of this publication may be reproduced in anyform, in an electronic retrieval system or otherwise,without prior written permission of ITI, 1250 Eye Street NW, Washington, DC 20005. Printed in the United States of AmericaCAUTION:
12、The developers of this standard have requested that holders of patents that may berequired for the implementation of the standard disclose such patents to the publisher. However,neither the developers nor the publisher have undertaken a patent search in order to identifywhich, if any, patents may ap
13、ply to this standard. As of the date of publication of this standardand following calls for the identification of patents that may be required for the implementation ofthe standard, no such claims have been made. No further patent search is conducted by the de-veloper or publisher in respect to any
14、standard it processes. No representation is made or impliedthat licenses are not required to avoid infringement in the use of this standard.Copyright American National Standards Institute Provided by IHS under license with ANSI Not for ResaleNo reproduction or networking permitted without license fr
15、om IHS-,-,-iContentsPageForeword .xiIntroduction .xiv1 Scope. 11.1 Introduction 11.2 Requirements precedence. 11.3 SCSI standards family . 22 References. 42.1 Normative references. 42.2 Approved references 42.3 References under development. 42.4 Other references 43 Definitions, symbols, abbreviation
16、s, and conventions . 53.1 Definitions 53.2 Acronyms. 123.3 Keywords . 123.4 Editorial conventions 133.5 Numeric conventions . 133.6 Notation conventions . 143.6.1 UML notation conventions . 143.6.1.1 Notation conventions overview 143.6.1.2 Constraint and note conventions . 143.6.1.3 Class diagram co
17、nventions 143.6.1.4 Object diagram conventions 183.6.2 Notation for procedure calls. 203.6.3 Notation for state diagrams 204 SCSI architecture model 224.1 Introduction 224.2 The SCSI distributed service model. 224.3 The SCSI client-server model 234.3.1 SCSI client-server model overview 234.3.2 Synch
18、ronizing client and server states 244.3.3 Request/Response ordering 244.4 The SCSI structural model. 254.5 SCSI classes 264.5.1 SCSI classes overview 264.5.2 SCSI Domain class 274.5.3 Service Delivery Subsystem class. 284.5.4 SCSI Device class . 294.5.4.1 SCSI Device class overview 29Copyright Ameri
19、can National Standards Institute Provided by IHS under license with ANSI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-iiPage4.5.4.2 SCSI Device Name attribute 294.5.5 SCSI Port class 304.5.5.1 SCSI Port class overview 304.5.5.2 Relative Port Identifier attribute
20、 . 314.5.6 SCSI Target Port class 314.5.6.1 SCSI Target Port class overview . 314.5.6.2 Target Port Identifier attribute 314.5.6.3 Target Port Name attribute 314.5.7 SCSI Initiator Port class. 324.5.7.1 SCSI Initiator Port class overview 324.5.7.2 Initiator Port Identifier attribute. 324.5.7.3 Initi
21、ator Port Name attribute. 324.5.8 Task Router class 324.5.9 SCSI Initiator Device class 334.5.10 Application Client class 344.5.11 Application Client Task Management Function class 344.5.11.1 Application Client Task Management Function class overview . 344.5.11.2 Function Identifier attribute 344.5.
22、11.3 Nexus attribute. 344.5.11.4 Service Response attribute 344.5.11.5 Additional Response Information attribute. 344.5.12 Application Client Task Set class. 354.5.13 Application Client Command class 354.5.13.1 Application Client Command class overview . 354.5.13.2 I_T_L_Q Nexus attribute 354.5.13.3
23、 CDB attribute . 354.5.13.4 Task Attribute attribute. 354.5.13.5 Status attribute. 354.5.13.6 Service Response attribute 354.5.13.7 Data-In Buffer attribute 354.5.13.8 Data-In Buffer Size attribute 354.5.13.9 Data-Out Buffer attribute 354.5.13.10 Data-Out Buffer size attribute 364.5.13.11 CRN attrib
24、ute . 364.5.13.12 Command Priority attribute 364.5.13.13 First Burst Enabled attribute 364.5.13.14 Sense Data attribute 364.5.13.15 Sense Data Length attribute 364.5.13.16 Status Qualifier attribute 364.5.14 SCSI Target Device class 364.5.15 Level 1 Hierarchical Logical Unit class 374.5.16 Level 2 H
25、ierarchical Logical Unit class 394.5.17 Level 3 Hierarchical Logical Unit class 394.5.18 Level 4 Hierarchical Logical Unit class 394.5.19 Logical Unit class. 404.5.19.1 Logical Unit class overview 404.5.19.2 LUN attribute 424.5.19.3 Logical Unit Name attribute . 424.5.19.4 Dependent Logical Unit att
26、ribute . 424.5.20 Device Server class . 434.5.21 Task Manager class. 434.5.22 Task Set class . 43Copyright American National Standards Institute Provided by IHS under license with ANSI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-iiiPage4.5.23 Command class . 43
27、4.5.23.1 Command class overview 434.5.23.2 I_T_L_Q Nexus attribute 434.5.23.3 Task Attribute attribute . 434.5.23.4 CDB attribute 444.5.23.5 CRN attribute . 444.5.23.6 Command Priority attribute 444.5.23.7 Status attribute . 444.5.23.8 Sense Data attribute 444.5.23.9 Sense Data Length attribute 444.
28、5.23.10 Service Response attribute 444.5.23.11 Status Qualifier attribute. 444.5.23.12 First Burst Enabled attribute. 444.5.23.13 Device Server Buffer attribute 444.5.23.14 Application Client Buffer Offset attribute 444.5.23.15 Request Byte Count attribute . 444.5.23.16 Delivery Result attribute . 4
29、44.5.24 Task Management Function class . 454.5.24.1 Task Management Function class overview 454.5.24.2 Function Identifier attribute. 454.5.24.3 Nexus attribute . 454.5.24.4 Service Response attribute 454.5.24.5 Additional Response Information attribute . 454.5.25 Well Known Logical Unit class . 454
30、.6 Logical unit number (LUN) . 464.6.1 Introduction 464.6.2 Logical unit representation format 464.6.3 LUNs overview . 464.6.4 Minimum LUN addressing requirements 464.6.5 Single level LUN structure 464.6.6 Eight byte LUN structure 484.6.7 Peripheral device addressing method 514.6.8 Flat space addres
31、sing method . 524.6.9 Logical unit addressing method . 534.6.10 Extended logical unit addressing . 544.6.11 Well known logical unit addressing 574.6.12 Extended flat space addressing method 574.6.13 Logical unit not specified addressing . 584.7 Nexus . 584.7.1 Nexus overview 584.7.2 Command identifi
32、er 594.7.3 Nexus usage rules . 594.8 SCSI ports 594.8.1 SCSI port configurations 594.8.2 SCSI devices with multiple ports 604.8.3 Multiple port SCSI target device structure 604.8.4 Multiple port SCSI initiator device structure . 614.8.5 Multiple port SCSI device structure 624.8.6 SCSI initiator devi
33、ce view of a multiple port SCSI target device 634.8.7 SCSI target device view of a multiple port SCSI initiator device 66Copyright American National Standards Institute Provided by IHS under license with ANSI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ivPage4.
34、9 The SCSI model for distributed communications. 665 SCSI command model. 715.1 The Execute Command procedure call . 715.2 Command descriptor block (CDB) . 725.3 Status. 735.3.1 Status codes 735.3.2 Status qualifier . 745.3.3 Status precedence. 765.4 SCSI transport protocol services in support of Exe
35、cute Command. 775.4.1 Overview 775.4.2 Command and status SCSI transport protocol services 775.4.2.1 Command and status SCSI transport protocol services overview. 775.4.2.2 Send SCSI Command SCSI transport protocol service request 785.4.2.3 SCSI Command Received SCSI transport protocol service indic
36、ation. 785.4.2.4 Send Command Complete SCSI transport protocol service response . 795.4.2.5 Command Complete Received SCSI transport protocol service confirmation 795.4.3 Data transfer SCSI transport protocol services . 805.4.3.1 Introduction 805.4.3.2 Data-In delivery service . 825.4.3.2.1 Send Dat
37、a-In SCSI transport protocol service request 825.4.3.2.2 Data-In Delivered SCSI transport protocol service confirmation . 825.4.3.3 Data-Out delivery service 825.4.3.3.1 Receive Data-Out SCSI transport protocol service request 825.4.3.3.2 Data-Out Received SCSI transport protocol service confirmatio
38、n. 835.4.3.4 Terminate Data Transfer service . 835.4.3.4.1 Terminate Data Transfer SCSI transport protocol service request 835.4.3.4.2 Data Transfer Terminated SCSI transport protocol service confirmation 845.5 Command lifetimes 845.6 Aborting commands. 855.7 Command processing example . 895.8 Comma
39、nds that complete with CHECK CONDITION status . 905.8.1 Overview 905.8.2 Handling commands when ACA is not in effect. 905.8.3 Aborting commands terminated with a CHECK CONDITION status without establishing an ACA . 905.9 Auto contingent allegiance (ACA) 915.9.1 ACA overview 915.9.2 Establishing an A
40、CA 925.9.3 Handling new commands received on the faulted I_T nexus when ACA is in effect 925.9.4 Handling new commands received on non-faulted I_T nexuses when ACA is in effect 93Copyright American National Standards Institute Provided by IHS under license with ANSI Not for ResaleNo reproduction or
41、networking permitted without license from IHS-,-,-vPage5.9.4.1 Command processing permitted for commands received on non-faulted I_T nexuses during ACA 935.9.4.2 Handling new commands received on non-faulted I_T nexuses when ACA is in effect 935.9.5 Clearing an ACA condition . 945.10 Overlapped comm
42、ands 955.11 Incorrect logical unit . 955.12 Task attribute exception conditions 955.13 Sense data . 965.14 Unit attention condition. 966 SCSI events and event notification model . 1006.1 SCSI events overview 1006.2 Establishing a unit attention condition subsequent to detection of an event 1026.3 Co
43、nditions resulting from SCSI events 1036.3.1 Power on 1036.3.2 Hard reset 1046.3.3 Logical unit reset 1046.3.4 I_T nexus loss 1046.3.5 Power loss expected 1056.4 Event notification SCSI transport protocol services . 1057 Task management functions 1077.1 Task management function procedure calls 1077.
44、2 ABORT TASK 1087.3 ABORT TASK SET 1097.4 CLEAR ACA. 1097.5 CLEAR TASK SET. 1097.6 I_T NEXUS RESET 1107.7 LOGICAL UNIT RESET . 1107.8 QUERY TASK 1107.9 QUERY TASK SET 1117.10 QUERY ASYNCHRONOUS EVENT 1117.11 Task management function lifetime . 1127.12 Task management SCSI transport protocol services
45、. 1137.12.1 Task management SCSI transport protocol services overview 1137.12.2 Send Task Management Request SCSI transport protocol service request 1137.12.3 Task Management Request Received SCSI transport protocol service indication. 114Copyright American National Standards Institute Provided by I
46、HS under license with ANSI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-viPage7.12.4 Task Management Function Executed SCSI transport protocol service response. 1147.12.5 Received Task Management Function Executed SCSI transport protocol service confirmation 115
47、7.13 Task management function example. 1158 Task set management . 1178.1 Introduction to task set management. 1178.2 Implicit head of queue 1178.3 Command management model . 1178.4 Command management events. 1188.5 Command states 1188.5.1 Overview 1188.5.1.1 Command state nomenclature. 1188.5.1.2 Su
48、spended information 1188.5.2 Enabled command state 1198.5.3 Blocked command state 1198.5.4 Dormant command state . 1198.5.5 Completed command state 1198.5.6 Command states and command lifetimes 1198.6 Task attributes . 1208.6.1 Overview 1208.6.2 Commands having the SIMPLE task attribute 1208.6.3 Com
49、mands having the ORDERED task attribute 1218.6.4 Commands having the HEAD OF QUEUE task attribute 1218.6.5 Commands having the ACA task attribute 1218.7 Command priority 1218.8 Command state transitions 1228.9 Task set management examples. 1238.9.1 Introduction 1238.9.2 Commands having the HEAD OF QUEUE task attribute 1248.9.3 Comman