HP OpenVMS systems documentation

The CALL_UNLOCK MACRO-32 macro facilitates the use of the MMG_STD$UNLOCK routine by code that was originally written to use the JSB-interface counterpart MMG$UNLOCK. The CALL_UNLOCK macro has implicit register inputs that correspond to the register inputs and outputs of the JSB-interface for the MMG$UNLOCK routine.

This macro has been modified to use the full 64-bits of the R3 input which contains the PTE address. The macro calls the new MMG_STD$IOUNLOCK_BUF routine instead of MMG_STD$UNLOCK. In addition, the CALL_UNLOCK macro has been modified to generate a suppressable interface warning at compile-time. The format of the macro call is:

CALL_UNLOCK [ INTERFACE_WARNING=YES|NO ]

By default the interface warning is enabled and generates the following warning at compile-time:

%AMAC-W-GENWARN, generated WARNING: 0 CALL_UNLOCK interface has changed for 64-bit virtual addressing; set INTERFACE_WARNING=NO to disable messages. %AMAC-W-GENWARN, generated WARNING: 0 CALL_UNLOCK uses the 64-bit PTE address in R3 %AMAC-W-GENWARN, generated WARNING: 0 CALL_UNLOCK does not unlock the page table pages %AMAC-W-GENWARN, generated WARNING: 0 A call to IOC_STD$RELEASE_DIOBM may be required to derive a SVAPTE

B.19 MMG_STD$SVAPTECHK, MMG$SVAPTECHK

The current versions of the MMG_STD$SVAPTECHK and MMG$SVAPTECHK routines compute a 32-bit svapte for either a process or system space address. As of OpenVMS Alpha Version 7.0, these routines are be restricted to an S0/S1 system space address and no longer accept an address in P0/P1 space. The MMG_STD$SVAPTECHK and MMG$SVAPTECHK routines check the full 64 bits of the input address and declare a bugcheck for an input address that is not in S0/S1 space. For S0/S1 input addresses, these routines return a 32-bit system virtual address of the PTE through the SPT window.

In releases prior to OpenVMS Alpha Version 7.0, the interface for this routine was:

void mmg_std$svaptechk (void *va, PCB *pcb, PHD *phd, void **svapte_p);

The new interface for this routine is:

void mmg_std$svaptechk (VOID_PQ va, PCB *pcb, PHD *phd, PTE **svapte_p);

The majority of callers of this routine use it with an S0/S1 address and do not need to change.

This appendix describes the new routines and macros available implementing for kernel threads.

In addition to a few new routines to convert a PID to a KTB address, the EXE$NAM_TO_PCB routine is modified to return the KTB address in R2, which previously was a scratch register. The new routines and macros all assume the caller is executing in kernel mode.

Converts an internal PID to a KTB address.

Format

EXE$CVT_IPID_TO_KTB ipid ,ktb ,pcb

RETURNS

OpenVMS usage	cond_value
type	longword (unsigned)
access	write only
mechanism	by value

Status indicating the success or failure of the operation.

Arguments

ipid

OpenVMS usage	process_id
type	longword (unsigned)
access	read
mechanism	by value

This argument provides the internal PID to be converted.

ktb

OpenVMS usage	address
type	quadword
access	write
mechanism	by reference

This argument provides the KTB address.

pcb

OpenVMS usage	address
type	quadword
access	write
mechanism	by reference

This argument provides the PCB address.

Description

The EXE$CVT_IPID_TO_KTB routine converts an internal PID to a KTB address.

Return Values

SS$_NONEXPR	The process does not exist.
SS$_NOSUCHTHREAD	The process exists but the thread does not.

Converts an external PID to a KTB address.

Format

EXE$CVT_EPID_TO_KTB epid ,ktb ,pcb

RETURNS

OpenVMS usage	cond_value
type	longword (unsigned)
access	write only
mechanism	by value

Status indicating the success or failure of the operation.

Arguments

epid

OpenVMS usage	process_id
type	longword (unsigned)
access	read
mechanism	by value

This argument provides the external PID to be converted.

ktb

OpenVMS usage	address
type	quadword
access	write
mechanism	by reference

This argument provides the KTB address.

pcb

OpenVMS usage	address
type	quadword
access	write
mechanism	by reference

This argument provides the PCB address.

Description

The EXE$CVT_EPID_TO_KTB routine converts an external PID to a KTB address.

Return Values

SS$_NONEXPR	The process does not exist.
SS$_NOSUCHTHREAD	The process exists but the thread does not.

Obtains the current process or thread KTB address. Applicable to BLISS, C, and MACRO-32. The following three command formats are for BLISS, C, and MACRO-32, respectively.

Format

GET_CURKTB;

GET_CURKTB()

GET_CURKTB ktbreg , pcbreg, [preserve][test_multi=yes]

Arguments

ktbreg

This argument is the destination to return the KTB address. The default is R14.

pcbreg

This argument is the register containing the address of the PCB. The default is R14.

preserve

This argument is optional. The default is YES to preserve R0 and R1. Otherwise, it is NO.

test_multi

This argument is optional. The default is YES to test and validate if there is more than one KTB. If NO, it is assumed that the process is already known to be multithreaded.

Description

The GET_CURKTB macro obtains the current process or thread KTB address.