Specifications

Data Structures
1.14 Object Rights Block (ORB)
Table 1–16 (Cont.) Contents of Object Rights Block
Field Name Contents
ORB$R_MIN_CLASS Minimum classification mask.
ORB$R_MAX_CLASS Maximum classification mask.
ORB$W_NAME_LENGTH Length of object name.
ORB$L_NAME_POINTER Pointer to object name.
ORB$L_OCB Pointer to object class block.
ORB$L_TEMPLATE_ORB Pointer to template ORB.
ORB$L_OBJECT_
SPECIFIC
Object class specific usage cell.
ORB$L_ORIGINAL_ORB Pointer to another ORB.
ORB$W_UPDSEQ Update sequence number.
ORB$L_MUTEX_
ADDRESS
Address of mutex for $CHKPRO.
1.15 SCSI Class Driver Request Packet (SCDRP)
The SCSI class driver allocates and builds a SCSI class driver request packet
(SCDRP) for each I/O request it services, passing it to the SCSI port driver. The
class driver routine initializes the SCDRP with the addresses of the UCB, SCDT,
and IRP and copies to it data obtained from the IRP. The SCDRP also contains
the addresses of the SCSI command buffer and status buffer.
The SCSI class driver passes the address of the SCDRP to the port driver in the
call to SPI$SEND_COMMAND.
The SCDRP is illustrated in Figure 1–18 and described in Table 1–17.
Figure 1–18 SCSI Class Driver Request Packet (SCDRP)
SCDRP$L_FQFL 0
SCDRP$L_FQBL 4
SCDRP$W_SCDRPSIZESCDRP$B_CD_TYPESCDRP$B_FLCK 8
SCDRP$L_FPC 12
SCDRP$L_FR3 16
SCDRP$L_FR4 20
SCDRP$L_PORT_UCB 24
SCDRP$L_UCB 28
SCDRP$W_FUNCSCDRP$W_STS 32
SCDRP$L_SVAPTE 36
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