1、ANSI INCITS 270-1996 (R2001)(formerly ANSI X3.270-1996 (R2001)for Information Technology SCSI-3 Architecture ModelANSI X3.270-1 996 American National Standard for Information Technology - SCSI-3 Architecture Model Secretariat Information Technology Industry Council Approved April 8, 1996 American Na
2、tional Standards - _ Institute, Inc. Abstract This standard specifies the SCSI Architecture Model. The purpose of the architecture is to pro- vide a common basis for the coordination of SCSI-3 standards and to specify those aspects of SCSI-3 I/O system behavior that are independent of a particular t
3、echnology and common to all implementations. AmericanNationalStandardApproval of an American National Standard 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 judgme
4、nt of the ANSI Board of StandardsReview, substantial agreement has been reached by directly and materiallyaffected interests. Substantial agreement means much more than a simplemajority, but not necessarily unanimity. Consensus requires that all views andobjections be considered, and that a concerte
5、d effort be made toward theirresolution.The use of American National Standards is completely voluntary; their existencedoes not in any respect preclude anyone, whether he has approved the standardsor not, from manufacturing, marketing, purchasing, or using products, processes,or procedures not confo
6、rming to the standards.The American National Standards Institute does not develop standards and will inno circumstances give an interpretation of any American National Standard.Moreover, no person shall have the right or authority to issue an interpretation ofan American National Standard in the nam
7、e of the American National StandardsInstitute. Requests for interpretations should be addressed to the secretariat orsponsor whose name appears on the title page of this standard.CAUTION NOTICE: This American National Standard may be revised orwithdrawn at any time. The procedures of the American Na
8、tional StandardsInstitute require that action be taken periodically to reaffirm, revise, or withdrawthis standard. Purchasers of American National Standards may receive currentinformation on all standards by calling or writing the American National StandardsInstitute.CAUTION: The developers of this
9、standard have requested that holders of patents that may be required for theimplementation of the standard disclose such patents to the publisher. However, neither the developers nor the publisherhave undertaken a patent search in order to identify which, if any, patents may apply to this standard.
10、As of the date ofpublication of this standard and following calls for the identification of patents that may be required for the implementationof the standard, no such claims have been made. No further patent search is conducted by the developer or publisher inrespect to any standard it processes. N
11、o representation is made or implied that licenses are not required to avoidinfringement in the use of this standard.Published byAmerican National Standards Institute11 West 42nd Street, New York, New York 10036Copyright 1996 by Information Technology Industry Council (ITI)All rights reserved.No part
12、 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 AmericaContents Page Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi 0 1 1.1 1.2 1.3 1.3.1 1.3.2 1.3.3 1.3.4 2 3 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.7.1 3.7.2 3.7.3 3.7.4 3.8 3.9 4 4.1 4.2 4.3 4.4 4.5 4.6 4.6.1 4.6.2 4.7 4.7.1 4.7.2 4.7.
14、3 4.7.4 4.8 5 5.1 5.1.1 5.1.2 5.2 5.3 Introduction . 1 Scope of the Architecture . 1 Scope of SCSI-3 Standards .2 Architecture Standard . .3 implementation Standards . 3 Commands . 3 Device Access Methods .3 SCSI-3 Protocol Standards 3 Interconnect Standards .3 Normative References .4 Glossary and C
15、onventions .4 Glossary . 4 References to SCSI Standards . .8 Acronyms and Abbreviations: . .8 Editorial Conventions 9 Numeric Conventions . .9 Reserved Fields and Codes .9 Objects and Object Notation . .9 Notation for Objects .9 Object Addresses and Identifiers . .I0 Predefined Objects . .I0 Hierarc
16、hy Diagrams .I0 Notation for Procedures and Functions .I1 State Diagram . .I3 SCSI-3 Architecture Model . .I4 Introduction .I4 The SCSI-3 Distributed Service Model .I5 The SCSI-3 Client-Server Model . .I6 The SCSI-3 Structural Model .18 SCSI Domain . .20 The Service Delivery Subsystem . .21 Synchron
17、izing Client and Server States . .22 Request/Response Ordering . .22 SCSI Device Models . .23 SCSI Initiator Model . .25 SCSI Target . .25 The Task Manager .26 Logical Unit .26 The SCSI-3 Model for Distributed Communications .28 SCSI Command Model . .31 Command Descriptor Block . .33 Operation Code
18、.34 Control Field .35 Status .36 Protocol Services in Support of Execute Command .37 I 5.3.1 5.3.2 5.3.3 5.4 5.5 5.5.1 . 5.5.2 5.6 5.6.1 5.6.2 5.6.3 5.6.4 5.6.5 5.6.6 6 6.1 6.2 .e 6.3 6.4 6.5 6.6 6.7 -_ - -$.8 7 4- 7.1 7.2 7.3 7.4 7.4.1 7.4.2 _ 7.4.3 7.4.4 7.5 7.5.1 7.5.2 7.5.3 7.5.4 7.6 7.6.1 7.6.2
19、 7.6.3 7.6.4 7.6.5 7.6.6 7.7 7.7.1 7.7.2 7.7.3 7.7.4 7.7.5 Page Data Transfer Protocol Services .38 Data-In Delivery Service . .39 Data-Out Delivery service 40 Task and Command Lifetimes . .40 Command Processing Examples . .41 Unlinked Command Example .41 Linked Command Example . .42 Command Process
20、ing Considerations and Exception Conditions 4 4 Auto Contingent Allegiance . .44 Overlapped Commands .45 Incorrect Logical Unit Selection . .46 Sense Data .46 Unit Attention Condition .48 Hard Reset . .49 Task Management Functions .49 ABORT TASK . .51 ABORT TASK SET . .51 CLEAR ACA . .52 CLEAR TASK
21、SET .52 TARGET RESET .52 TERMINATE TASK . .52 Task Management Protocol Services .53 Task Management Function Example .54 Task Set Management .55 Terminology . .56 Task Management Events . .56 Task Abort Events .57 Task States .57 Enabled . .57 Blocked .58 Dormant . .58 Ended .58 Task Attributes . .5
22、8 SIMPLE Task . .59 ORDERED Task .59 HEAD OF QUEUE Task .59 ACA Task . .59 Task State Transitions . 59 Transition SO:Sl (ordered task) .60 Transition SO:Sl (simple task) .60 Transition SO:S3; S2:S3 . .61 Transiiton Sl :S2 . .61 Transition Sl :S3 . .61 Transition S2:Sl . .61 Task Set Management Examp
23、les .61 Blocking Boundaries . .61 HEAD OF QUEUE Tasks .62 Ordered Tasks . .63 ACA Task . .65 Deferred Task Completion .66 ii -_ -. - z 4- Page Object Definitions 1 SCSI Domain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24、. . . . . . . . . . . . . . . . . . . 20 2 Service Delivery Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 3 SCSI Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 4 Initiator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5 Target . . . . . . . . . . . .
26、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 6 Logical Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
27、. . . . . . . . . . . . . . . . . . . . . 27 7 Task . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Figures 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 2
28、0 21 22 23 24 25 26 Requirements Precedence .l Functional Scope of SCSI-3 Standards .2 Example of Hierarchy Diagram .12 State Diagram . .14 Client-Server Model .16 SCSI Client-Server Model . .I7 SCSI I/O System and Domain Model .18 SCSI Hierarchy . .19 Domain Functional Model .20 Domain Hierarchy .
29、.20 Service Delivery Subsystem Hierarchy . .21 SCSI Device Functional Models . .23 SCSI Device Hierarchy Diagram .24 Target Object Hierarchy .25 Logical Unit Object Hierarchy .26 Protocol Service Reference Model . .29 Protocol Service Model . .30 Request-Response ULP Transaction and Related LLP Serv
30、ices 3 1 Model for buffered data transfers . .38 Command processing events . .42 Linked Command Processing Events . .43 Task Management Request Processing . .55 Example of Dormant Task Behavior . .58 Task States .60 HEAD OF QUEUE Tasks .62 HEAD OF QUEUE Tasks and Blocking Boundaries . .63 . III Page
31、 27 Ordered Tasks and Blocking Boundaries .64 28 ACA Task Example . .65 29 Example of Deferred Task Completion . .66 Tables . 1 Format of Command Descriptor Block .34 2 Operation Code .35 3 Control Field . .35 4 Status Codes .36 -_ -.- - -_ 4- iv Foreword (This foreword is not part of American Natio
32、nal Standard X3.270-1996.) The purpose of this standard is to provide a basis for the coordination of SCSI-3 standards development and to define requirements, common to all SCSI-3 technologies and implementations, which are essential for compat- ibility with host SCSI-3 application software and devi
33、ce-resident firmware across all SCSI-3 protocols. These requirements are defined through a ref- erence model which specifies the behavior and abstract structure which is generic to all SCSI-3 I/O system implementations. As with any other technical document, there may arise questions of inter- pretat
34、ion as new products are implemented. The X3 Committee has established procedures to issue technical opinions concerning the stan- dards developed by the X3 organization. These procedures may result in SCSI Technical Information Bulletins being published by X3. These bulletins, while reflecting the o
35、pinion of the Technical Committee which developed the standard, are intended solely as supplementary infor- mation to other users of the standard. This standard, ANSI X3.270-1996, as approved through the publication and voting procedures of the American National Standards Institute, is not altered b
36、y these Bulletins. Any subsequent revision to this standard may or may not reflect the con- tents of these Technical Information Bulletins. Requests for interpretation, suggestions for improvement or addenda, or This standard was processed and approved for submittal to ANSI by the Accreditel Standar
37、ds Comr.G+- Illlree onlnformatron Techr;otogy;)(3; Committee approval of this standard does not necessarily imply that all committee members voted for its approval. At the time it approved this standard, the X3 Committee had the following members: James D. Converse, Chair Donald C. Loughry, Vice-Cha
38、ir Kate McMillan, Secretary Organization Represented Name of Representative American Nuclear Society . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Geraldine C. Main Sally Hartzell (Alt.) AMP, Inc. . . . . . . . . . . . . . . . . . . . . . . . . .
39、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Edward Kelly Charles Brill (Alt.) Apple Computer, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . David K. Michael Jerry Kellenben
40、z (Alt.) AT;.;.;.;.;.;.;.; ; . . . . ;. Ed Cikkoia Digital Equipment Corporation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scott K. Jameson Richard Hovey (Alt.) Eastman Kodak Company . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
41、 . . . . . . . . . . . . . James D. Converse Michael Nier (Alt.) Hewlett-Packard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Donald C. Loughry Karen Higginbottom (Alt.) Hitachi America, Ltd. . . . . . . . . . . . . .
42、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . John Neumann Kei Yamashita (Alt.) Hughes Aircraft Company . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Harold Zebrack V Organization Represented Name of Rep
43、resentative IBM Corporation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Joel Urman Mary Anne Lawler (Ah.) Institute for Certification of Computer Professionals (ICCP) . . . . . . . . . . . . . . . . . . . . . . . . .
44、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Kenneth Zemrowski National Communications Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dennis Bodson Granger Kelley (AIL) National Institute of Standards and Technology . . . . . . . . . . . . . . . . . .
45、 Michael Hogan James H. Burrows (Alt.) 1 Northern Telecom, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mel W oinsky John Pugh (Alt.) Share, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
46、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gary Ainsworth David Thewlis (Alt.) Storage Technology Corporation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Joseph S. Zajaczkowski Samuel D. Cheatham (Alt.) Sun Microsystems, Inc . . . . . . . . . . . .
47、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gary S. Robinson Sybase, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Donald Ft. Deutsch Texas Instruments, Inc. .
48、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clyde Camp Fritz Whittington (AIL) 3M Company . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Eddie T. Mo
49、rioka Paul D. Jahnke (Alt.) Unisys Corporation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . John L. Hill Stephen P. Oksala (Alt.) U.S. Department of Defense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Jerry L. Smith *L C. J. Pasquariello (Alt.) U.S. Department of Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Carol S. Blackston Bruce Ft. White (Alt.) Xerox Corporation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
