Sim queue operations, Sim queue, Operations – HP Integrity NonStop H-Series User Manual
Page 30
Interfacing With the Open SCSI I/O Process (IOP)
SIM Queue Operations
SIM Queue Operations
The Open SCSI implementation of the SCSI interface module (SIM) queue and its
operations is derived from the existing queuing mechanism within the I/O subsystem.
These rules of operation are specific to the Open SCSI interface:
4
Peripheral driver pointer
Yes
4
Next CCB pointer
Yes
4
Request mapping information
No
4
Callback on completion
No
4
Data-buffer pointer: byte offset of data buffer from
start of WRITEREAD buffer (not used for
scatter/gather list)
Yes
4
Data transfer length
Yes
4
Sense-buffer pointer: byte offset of sense buffer from
start of WRITEREAD buffer
Yes
1
Sense-buffer length
Yes
1
Command descriptor block (CDB) length: must be
one of the three values 6, 10, or 12
Yes
2
Number of scatter/gather entries
No
4
Vendor-unique (VU) field
No
1
SCSI status
Yes
1
Autosense residual length
Yes
2
(Reserved)
-
4
Residual length
Yes
12
Command descriptor block (CDB)
Yes
4
Timeout value
Yes
4
Message-buffer pointer (target only)
No
2
Message-buffer length (target only)
No
2
Vendor-unique (VU) flags
No
1
Tagged queue action
No
1
Tag ID (target only)
No
1
Initiator ID (target only)
No
1
(Reserved)
-
n
Private data
No
Table 3-5. CCB Structure for Execute SCSI I/O (page 2 of 2)
Size of Field
(in bytes)
Description
Supported by
Open SCSI IOP?