Sony SDX-700C Product Specifications Manual page 118

6.Command Specification
Additional Length: This field contains a counter of the number of bytes to follow in Reservation descriptor. If the
allocation length specified by the PERSISTENT RESERVE IN command is not sufficient to contain the entire
parameter list, then only the bytes from 0 to the maximum allowed allocation length shall be sent to the application
client. The incremental remaining bytes shall be truncated, although the Additional Length field shall still contain the
actual number of bytes of Reservation descriptor and shall not be affected by the truncation. This shall not be
considered an error.
Reservation descriptor: The format of this field is defined in table 6-51.
Table 6-51: PERSISTENT RESERVATION IN Reservation Descriptor
Bit 7
Byte
0 (MSB)
7
8 (MSB)
11
12
13
14
15
The Reservation descriptor for each reservation shall contain the Reservation Key under which the persistent
reservation is held. The TYPE and SCOPE of each persistent reservation as present in the PERSISTENT
RESERVE OUT command that created the persistent reservation shall be returned.
SCOPE-SPECIFIC Address: The drive does not support an Element reservation. This field shall be set to zero.
SCOPE: The value in this field indicates whether a persistent reservation applies to an entire logical unit ot an
element. The value in this field are defined in table 6-52.
Code
0h Logical Unit
1h
2h Element (not supported in this drive)
3h-fh Reserved
Logical Unit: A SCOPE value of Logical Unit indicates that the persistent reservation applies to the entire logical
unit. The Logical Unit scope shall be implemented by all device server that implement PERSISTENT RESERVE
OUT.
Element: A SCOPE field value of Element indicates that the persistent reservation applies to the element of the
logical unit defined by the SCOPE-SPECIFIC Address field in the PERSISTENT RESERVE OUT parameter list.
The drive do not support it.
TYPE: The value in the TYPE field specify the characteristics of the persistent reservation being established for all
data blocks within the element or within the logical unit. Table 6-53 defines the characteristic of the different type
values. For each persistent reservation type, table 6-53 lists code value and describes the required device server
support. In this table, the description of required device server support is divided in two paragraphs. The first
paragraph defines the required handling for read operations. The second paragraph defines the required handling
for write operations.
6-68
6 5
SCOPE-SPECIFIC Address
SCOPE
Table 6-52: PERSISTENT RESERVATION SCOPE Codes
Name
Persistent reservation applies to the full logical unit
Obsolete
Persistent reservation applies to the specified element
Reserved
4 3
Reservation Key
(0 0 0 0)
Reserved
Obsolete
Description
SONY AIT-3 drive SDX-700 series Ver.2.1
PERSISTENT RESERVE IN
2 1
(LSB)
(LSB)
TYPE
0