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Quantum 10K II User Manual

Page 184

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SCSI Description

Quantum Atlas 10K II Ultra160/m SCSI Hard Disk Drives

5–117

PERSISTENT RESERVATION IN Command (5Eh) (continued)

The figure and table below illustrate and describe the data fields of each Read
Reservations descriptor’s data fields.

Bit

Byte

7

6

5

4

3

2

1

0

0 - 7

(MSB)

Reservation Key

(LSB)

8 - 11

(MSB)

Scope-Specific Address

(LSB)

12

Reserved

13

Scope

Type

14 - 15

(MSB)

Extent Length

(LSB)

Figure 5–53 PERSISTENT RESERVATION IN Read Reservations Descriptor —

Data Format

Table 5–55 PERSISTENT RESERVATION IN Read Reservations Descriptor — Field

Descriptions

Data Field

Description

Reservation Key

The Reservation key field contains an 8-byte value that identifies the
reservation key under which the persistent reservation is held.

Scope-Specific
Address

If the Scope field (Byte 13, bits 4 – 7) represents an “Extent” reservation, the
Scope-Specific Address field contains the logical block address (LBA) of the
first block of the extent and the Extent Length field (Bytes 14 – 15) contains
the number of blocks in the extent.
If the Scope field represents an “Element” reservation, the Scope-Specific
Address field contains the Element address, zero-filled in the most
significant bytes to fit the field and the Extent Length field is set to zero.

(continued)