SCSI Primary Commands - 2.pdf

T10/1236-D Revision 20 18 July 20017.16 RELEASE(10) command7.16.1 RELEASE(10) command introductionThe RELEASE(10) command (see table 94) is used to release a previously reserved logical unit.Table 94 — RELEASE(10) commandBitByte7 6 5 4 3 2 1 00 OPERATION CODE (57h)1 Reserved 3RDPTY Reserved LONGID Obsolete2 Obsolete3 THIRD-PARTY DEVICE ID4 Reserved5 Reserved6 Reserved7 (MSB)PARAMETER LIST LENGTH8 (LSB)9 CONTROLThe RESERVE and RELEASE commands provide a basic mechanism for contention resolution in multiple-initiatorsystems. See 5.5.1 for a general description of reservations and the commands that manage them. A reservationmay only be released by a RELEASE command from the initiator that made it. It is not an error for an applicationclient to attempt to release a reservation that is not currently valid, or is held by another initiator. In this case, thedevice server shall return GOOD status without altering any other reservation.Byte 1 Bit 0 and Byte 2 provide an obsolete way to release previously reserved extents within a logical unit. If Byte1, Bit 0 is equal to one, device servers not implementing the obsolete capability shall terminate the command withCHECK CONDITION status and the sense key shall be set to ILLEGAL REQUEST.7.16.2 Logical unit releaseLogical unit reservation release is mandatory if the RELEASE(10) command is implemented. This command shallcause the device server to terminate all non-third-party logical unit reservations that are active from the initiator tothe specified logical unit.7.16.3 Third-party releaseThird-party reservation release is mandatory if the RELEASE(10) command is implemented. Third-party releaseallows an application client to release a logical unit that was previously reserved using third-party reservation (see7.21.3). Third-party release shall be implemented. It is intended for use in multiple-initiator systems that use theCOPY and EXTENDED COPY commands.If the third-party (3RDPTY) bit is zero, then a third-party release is not requested. If the 3RDPTY bit is zero then theLONGID bit and the PARAMETER LIST LENGTH field shall be ignored. If the 3RDPTY bit is one then the device servershall release the specified logical unit, but only if the initiator ID, 3RDPTY bit, and THIRD-PARTY DEVICE ID are identicalwhen compared to the RESERVE command that established the reservation.128 dpANS SCSI Primary Commands - 2 (SPC-2)