Maxtor 10K V Computer Drive User Manual


 
5-90 Maxtor Atlas 10K V
Table 5-117 PERSISTENT RESERVATION OUT Parameter List-Field Descriptions
Data Field Description
Reservation Key
This field contains an 8-byte token that is provided by the application client to the device server
to identify which initiator is the source of the PERSISTENT RESERVATION OUT command.
The device server verifies that the Reservation Key in the PERSISTENT RESERVATION OUT
command matches the Reservation Key that is registered for the initiator from which the com-
mand is received. If there is no match, the device server returns a RESERVATION CONFLICT
status. The Reservation Key of the initiator is valid for all Service action and Scope values.
Service Action
Reservation Key
This field contains information needed for 3 service actions: the Register service action, the Pre-
empt service action, and the Pre-empt & Clear service action. The Service Action Reservation Key
is ignored for all other service actions.
For the Register service action, the Service Action Reservation Key field contains the new Reser-
vation Key to be registered.
For the Pre-empt and the Pre-empt & Clear service actions, the Service Action Reservation Key
contains the reservation key of the persistent reservations that are being pre-empted. For the Pre-
empt and the Pre-empt & Clear actions, any failure of the Service Action Reservation Key to
match any registered keys results in the device server returning a RESERVATION CONFLICT
status.
Scope-Specific
Address
If the Scope is an Extent reservation, this field contains the Logical Block Address of the extent
and the Extent Length field (bytes 22 – 23) contain the number of blocks in the extent.
If the Scope signifies an Element reservation, the Scope-Specific Address field contains the Ele-
ment Address, zero-filled in the most significant bytes to fit the field; the Extent Length is set to 0.
If the Service action is Register or Clear, or if the Scope is a Logical Unit reservation, both the
Scope-Specific Address and Extent Length fields are set to 0.
APTPL
Activate Persist Through Power Loss. This bit is valid only for Register service actions; it is ig-
nored for all other types of service actions.
Support for APTPL set to 1 is optional. If a device server that does not support APTPL receives a
1 in that bit in a Register service action, it returns a CHECK CONDITION status, with the sense
key set to ILLEGAL REQUEST and additional sense data set to INVALID FIELD IN PARAM-
ETER LIST.
If the last valid APTPL bit value received by the device server is 0, the loss of power in the target
releases any persistent reservations and removes all reservation keys. If the last valid APTPL bit
value is 1, the logical unit retains all persistent reservations and all reservation keys for all initia-
tors even if power is lost and later returned. The most recently received valid APTPL value from
any initiator governs the logical unit’s behavior in the event of a power loss.