Open SCSI Integrator's Manual for NonStop S-Series Servers

The Open SCSI I/O Process (IOP)
Open SCSI Integrator’s Manual for NonStop Servers—422988-002
4-11
The CAM Control Block (CCB)
CCB Structures
The descriptions of the various CCB structures in this subsection show that the first field
in each of the CCB structures is labeled “Address of this CCB.” The following
information is important for this field:
•
The IOP does not use this value while executing the operation.
•
The IOP uses this value only for an Abort SCSI Command operation. When
executing an Abort SCSI Command operation, the application or peripheral driver
should place in the “Address of CCB to be acted upon” field of the Abort SCSI
Command CCB the same value that it originally placed in the “Address of this
CCB” field of the CCB for the CAM operation it wants to abort (see Table 4-4
on
page 4-13).
This means that the application or peripheral driver need only make sure that the
value in the “Address of this CCB” field is unique for all operations it has
outstanding in an IOP at any one time, so that the application or driver will be able
to abort this operation, if needed.
6 Initiate synchronous transfers
1 = Initiates
0 = No effect
Yes Supported only with
the Set I/O
Characteristics
operation.
5 Disable synchronous transfers
1 = Disables
0 = No effect
Yes Supported only with
the Set I/O
Characteristics
operation.
4 SIM queue priority
1 = Priority insert in SIM queue
0 = Normal insert in SIM queue
Yes See SIM Queue
Operations on
page 4-15 for
restrictions, use, and
implementation.
3 SIM queue freeze No
2 SIM queue unfreeze
1 = Unfreeze SIM queue
0 = No effect
Yes See SIM Queue
Operations on
page 4-15 for
restrictions, use, and
implementation.
1 Engine synchronize No
0(Reserved) -
3 7-0 Denote physical versus virtual address No
4 7-0 Describe target mode attributes No
Table 4-2. Cam-Flag Bits (page 2 of 2)
Flag
Byte Bits Description
Supported
by Open
SCSI
IOP? Notes