Reserve - IBM Ultrastar 36LZX Specifications

8.30 RESERVE (56)

Byte
7 6
0
1 Reserved = 0
2
3
4
5
6
7 (MSB) Extent List Length = 0
8
9 VU = 0
Figure 142. RESERVE (56)
The Reserve command is used to reserve a LUN for an Initiator. This reservation can be either for the
Initiator sending the command or for a third party as specified by the Initiator.
Extents are not supported by the drive. The Ext bit must be zero. If Ext bit is set to one, Check Condition
Status is returned with a Sense Key of Illegal Request and additional sense code of Invalid Field in CDB
The Reservation Identification and Extent List Length fields are ignored.
The Reserve command requests that the entire Lun be reserved for the Initiator until
Ÿ the reservation is superseded by another valid Reserve command from the Initiator that made the
reservation.
Ÿ the reservation is released by a Release command from the same Initiator.
Ÿ a hard Reset condition occurs.
Ÿ a Bus Device Reset message is received from any Initiator.
Ÿ a power off/on cycle occurs.
The 3rdPty bit of zero indicates that the Initiator that issued the Reserve command is the Initiator for
which the LUN is reserved.
The 3rdPty bit of one indicates that this is a third-party reservation. The 3rd Party ID byte specifies the ID
of the third party for which the LUN is reserved. A reservation made with the 3rdPty bit of one and the
3rd Party ID byte set to the Initiator that issued this Reserve command is considered equivalent to a
reservation made with the 3rdPty bit set to zero.
Only the Initiator that issued the Reserve command for a LUN may release the LUN, regardless of the
3rdPty option. This Initiator may also release the LUN by issuing another Reserve command. This
superseding Reserve command releases the previous reservation when the new reservation is granted.
Reservation queuing is not supported by the drive. If a LUN is reserved and a Reserve command is
issued from a different initiator, the Target responds with a reservation Conflict.
Bit
5 4 3
Command Code = 57h
3rdPty
Reservation Identification
Third Pary Device ID
Reserved = 0
Reserved = 0
Reserved = 0
Reserved = 0
Ultrastar 36LZX hard disk drive specifications
2 1 0
Ext =
Reserved
0
(LSB)
FLAG LINK
165