Maxtor 10K V - Manual (Page 134)

5-76 Maxtor Atlas 10K V
Table 5-107
Read Reservations Parameters-Field Descriptions
The data format and field descriptions for the PERSISTENT RESERVATION IN
Read Reservations Descriptor are described in Table 5-108 and Table 5-109
respectively.
Table 5-108
PERSISTENT RESERVATION IN Read Reservations Descriptor-Data Format
Data Field Description
Generation
The value in this field is a 32-bit counter in the device server that is incremented each time a PER-
SISTENT RESERVATION OUT command requests a Register, Clear, Pre-empt, or Pre-empt and
Clear operation. Note that PERSISTENT RESERVATION IN commands do not increment the
counter, nor do PERSISTENT RESERVATION OUT commands that perform a Reserve or Re-
lease service action, or by a PERSISTENT RESERVATION OUT command that is not done due
to an error or a reservation conflict. The value in the Generation field is set to 0 as part of the power
on or reset processes.
The value in the Generation field allows the application client that examines the value to verify
that the configuration of the initiators attached to a logical unit has not been modified by another
application client without any notification of the application client doing the examination.
Additional
Length
This field contains the count of the number of bytes of Reservation descriptors (bytes 8 – n). Note
that this field contains the number of bytes regardless of the value prescribed by the Allocation
Length field in the command’s CDB.
Reservations De-
scriptors
One Reservation descriptor is reported for each unique persistent reservation on the logical unit
when the PERSISTENT RESERVATION IN command has indicated a Read Reservations action.
Table 5-112 and Table 5-109 detail the contents of each Reservation Descriptors field.
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)