OpenVMS System Services Reference Manual

Document revision date: 30 March 2001

OpenVMS System Services Reference Manual

Contents

Index

Using the $CRMPSC_GDZRO_64 service always implies that the SEC$M_WRT flag is set and that you want to map the section for writing. If you want to use this service to create a section with shared page tables for read only access, you must use private page tables and you cannot specify a shared page table region into which to map the section.

If the condition value SS$_ACCVIO is returned by this service, a value cannot be returned in the memory locations pointed to by the return_va_64 and return_length_64 arguments and, if specified as a nonzero value, the reserved_length_64 argument.

If a condition value other than SS$_ACCVIO is returned, the returned address and returned length indicate the pages that were successfully mapped before the error occurred. If no pages were mapped, the return_va_64 argument contains the value --1.

If the service returns an error status value other than SS$_INSFLPGS or SS$_MRES_PFNSMALL, a value is not returned in the reserved_length_64 argument.

If the service returns a successful condition value or if SS$_INSFLPGS or SS$_MRES_PFNSMALL is returned and the reserved_length_64 argument is specified as a nonzero address, the length in bytes of the global section as registered in the Reserved Memory Registry is returned in the reserved_length_64 argument.

Required Privileges

To create a global section, the process must have the following privileges:

SYSGBL privilege to create a system global section (if flag SEC$M_SYSGBL is set)
PRMGBL privilege to create a permanent global section
VMS$MEM_RESIDENT_USER rights identifier to create a memory-resident section
SHMEM privilege on OpenVMS Galaxy systems to create an object in Galaxy shared memory

Required Quota

If private page tables are used to map to the memory-resident global section, the working set limit quota (WSQUOTA) of the process must be sufficient to accommodate the increased size of the process page tables required by the increase in virtual address space.

If private page tables are used to map to the memory-resident global section, the page file quota (PGFLQUOTA) of the process must be sufficient to accommodate the increased size of the process page tables required by the increase in virtual address space.

Related Services

$CREATE_GDZRO, $CREATE_GPFILE, $CREATE_REGION_64, $CRMPSC, $CRMPSC_FILE_64, $CRMPSC_GFILE_64, $CRMPSC_GPFN_64, $CRMPSC_PFN_64, $DELETE_REGION_64, $DELTVA_64, $DGBLSC, $LCKPAG_64, $LKWSET_64, $MGBLSC_64, $PURGE_WS, $SETPRT_64, $ULKPAG_64, $ULWSET_64, $UPDSEC_64, $UPDSEC_64W

Condition Values Returned

SS$_NORMAL The service completed successfully. The specified global section already exists and has been mapped.

SS$_CREATED The service completed successfully. The global section has been created.

SS$_CREATED_SHPT Global section has been created with shared page tables.

SS$_ACCVIO The gs_name_64 argument cannot be read by the caller, or the return_va_64 or return_length_64 argument cannot be written by the caller.

SS$_BADRAD The specified RAD contains no memory, or if the specified RAD is greater than or equal to the maximum number of RADs on the system.

SS$_EXPGFLQUOTA The process's page file quota is not large enough to accommodate the increased virtual address space.

SS$_GBLSEC_MISMATCH Global section type mismatch. The specified global section was found; however, it is not a memory-resident section.

SS$_GPTFULL There is no more room in the system global page table to set up page table entries for the global section or for the shared page tables.

SS$_GSDFULL There is no more room in the system space allocated to maintain control information for global sections.

SS$_INSFLPGS Insufficient fluid pages available.

SS$_INSFRPGS Insufficient free shared pages or private pages.

SS$_INSFWSL The process's working set limit is not large enough to accommodate the increased virtual address space.

SS$_INV_SHMEM Shared memory is not valid.

SS$_IVACMODE The specified access mode is greater than PSL$_USER, or the caller's mode is less privileged than the create mode associated with the region.

SS$_IVLOGNAM The specified global section name has a length of 0 or has more than 43 characters.

SS$_IVPROTECT The protection argument format is invalid.

SS$_IVREGID An invalid region ID was specified.

SS$_IVSECFLG An invalid flag, a reserved flag, or an invalid combination of flags was specified.

SS$_IVSECIDCTL The match control field of the global section identification is invalid.

SS$_LEN_NOTPAGMULT The length_64 argument is not a multiple of CPU-specified pages. Or, if a shared page table region is specified by the region_id_64 argument, the map_length_64 argument is not a multiple of CPU-specific page table pages.

SS$_LOCK_TIMEOUT An OpenVMS Galaxy lock timed out.

SS$_MRES_PFNSMALL Preallocated, contiguous, aligned physical memory specified in the Reserved Memory Registry is smaller than the length specified for the memory-resident global section by the length_64 argument.

SS$_NOBREAK An OpenVMS Galaxy lock is held by another node and was not broken.

SS$_NOMEMRESID The process attempted to create a memory-resident section, but was not holding the right identifier VMS$MEM_RESIDENT_USER.

SS$_NOPRMGBL The process does not have the privileges to create or delete a permanent group global section (PRMGBL).

SS$_NOSYSGBL The process does not have the privileges to create or delete a system global section (SYSGBL).

SS$_OFF_NOTPAGALGN The section_offset_64 argument is not CPU-specific page aligned. Or, if a shared page table region is specified by the region_id_64 argument, the section_offset_64 argument is not CPU-specific page table page aligned.

SS$_OFFSET_TOO_BIG The section_offset_64 argument specified is beyond the logical end-of-file.

SS$_PAGNOTINREG A page in the specified input address range is not within the specified region.

SS$_PAGOWNVIO A page in the specified input address range is owned by a more privileged access mode.

SS$_REGISFULL The specified virtual region is full; no space is available in the region for the pages created to contain the mapped section.

SS$_SECREFOVF The maximum number of references for a global section has been reached (2,147,483,647).

SS$_SECTBLFUL There are no entries available in the system global section table for the global section or for the shared page tables.

SS$_TOOMANYLNAM The logical name translation of the gs_name_64 argument exceeded the allowed depth of 10.

SS$_VA_IN_USE A page in the specified input address range is already mapped and the flag SEC$M_NO_OVERMAP is set, or a page in the specified input address range is in another region, in system space, or inaccessible; or, the existing underlying page cannot be deleted because it is associated with a buffer object.

SS$_VA_NOTPAGALGN The start_va_64 argument is not CPU-specific page aligned. Or, if a shared page table region is specified by the region_id_64 argument, the start_va_64 argument is not CPU-specific page table page aligned.

$CRMPSC_GFILE_64 (Alpha Only)

On Alpha systems, allows a process to create a global disk file section and to map a section of its address space to the global section.
This service accepts 64-bit addresses.

Format

SYS$CRMPSC_GFILE_64 gs_name_64 ,ident_64 ,file_offset_64 ,length_64 ,chan ,region_id_64 ,section_offset_64 ,acmode ,flags ,return_va_64 ,return_length_64 [,fault_cluster
[,start_va_64 [,map_length_64]]]

C Prototype

int sys$crmpsc_gfile_64 (void *gs_nam_64, struct _secid *ident_64, unsigned __int64 file_offset_64, unsigned __int64 length_64, unsigned short int chan, struct _generic_64 *region_id_64, unsigned __int64 section_offset_64, unsigned int acmode, unsigned int flags, void *(*(return_va_64)), unsigned __int64 *return_length_64,...);

Arguments

gs_name_64

OpenVMS usage: section_name

type: character-coded text string

access: read only

mechanism: by 32- or 64-bit descriptor--fixed-length string descriptor

Name of the global section. The gs_name_64 argument is the 32- or 64-bit virtual address of a naturally aligned 32- or 64-bit string descriptor pointing to this name string.
ident_64

OpenVMS usage: section_id

type: quadword (unsigned)

access: read only

mechanism: by 32- or 64-bit reference

Identification value specifying the version number of a global section. The ident_64 argument is a quadword containing three fields. The ident_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword that contains the identification value.
The first longword specifies the matching criteria in its low-order 2 bits. The valid values, symbolic names by which they can be specified, and their meanings are as follows:

Value Symbolic Name Match Criteria

0 SEC$K_MATALL Match all versions of the section.

1 SEC$K_MATEQU Match only if major and minor identifications match.

2 SEC$K_MATLEQ Match if the major identifications are equal and the minor identification of the mapper is less than or equal to the minor identification of the global section.

When a section is mapped at creation time, the match control field is ignored. If you specify the ident_64 argument as 0, the version number and match control fields default to 0.
The version number is in the second longword. The version number contains two fields: a minor identification in the low-order 24 bits and a major identification in the high-order 8 bits. You can assign values for these fields by installation convention to differentiate versions of global sections. If no version number is specified when a section is created, processes that specify a version number when mapping cannot access the global section.
file_offset_64

OpenVMS usage: byte offset

type: quadword (unsigned)

access: read only

mechanism: by value

Byte offset into the file that marks the beginning of the section. The file_offset_64 argument is a quadword containing this number. If you specify the file_offset_64 argument as 0, the section is created beginning with the first byte in the file.
The file offset specified must be a multiple of virtual disk blocks.
length_64

OpenVMS usage: byte count

type: quadword (unsigned)

access: read only

mechanism: by value

Length, in bytes, of the global disk file section to be created. The length specified must be 0 or a multiple of virtual disk blocks. If the length specified is 0 or extends beyond the end-of-file (EOF), the global disk file section is created up to and including the virtual block number that contains EOF.
chan

OpenVMS usage: longword

type: longword (unsigned)

access: read only

mechanism: by value

Number of the channel on which the file has been accessed. The chan argument is a longword containing this number. The access mode at which the channel was opened must be equal to or less privileged than the access mode of the caller.
You can use the OpenVMS Record Management Services (RMS) macro $OPEN to access a file; the file options parameter in the file access block must indicate a user file open (UFO) keyword.
region_id_64

OpenVMS usage: region identifier

type: quadword (unsigned)

access: read only

mechanism: by 64 bit reference

The region ID associated with the region in which to map the global disk file section. The file VADEF.H in SYS$STARLET_C.TLB and the $VADEF macro in STARLET.MLB define a symbolic name for each of the three default regions in P0, P1, and P2 space.
The following region IDs are defined:

Symbol Region

VA$C_P0 Program region

VA$C_P1 Control region

VA$C_P2 64-bit program region

Other region IDs, as returned by the $CREATE_REGION_64 service, can be specified.
section_offset_64

OpenVMS usage: byte offset

type: quadword (unsigned)

access: read only

mechanism: by value

Offset into the global section to start mapping into the process's virtual address space. The offset specified must be a multiple of virtual disk blocks.
acmode

OpenVMS usage: access_mode

type: longword (unsigned)

access: read only

mechanism: by value

Access mode that is to be the owner of the pages created during the mapping. The acmode argument is a longword containing the access mode.
The $PSLDEF macro in STARLET.MLB and the file PSLDEF.H in SYS$STARLET_C.TLB define the following symbols and their values for the four access modes:

Value Symbolic Name Access Mode

0 PSL$C_KERNEL Kernel

1 PSL$C_EXEC Executive

2 PSL$C_SUPER Supervisor

3 PSL$C_USER User

The most privileged access mode used is the access mode of the caller.
Address space cannot be created within a region that has a create mode associated with it that is more privileged than the caller's mode. The condition value SS$_IVACMODE is returned if the caller is less privileged than the create mode for the region.
flags

OpenVMS usage: mask_longword

type: longword (unsigned)

access: read only

mechanism: by value

Flag mask specifying the characteristics of the global section to be created. The flags argument is a longword bit vector in which each bit corresponds to a flag. The $SECDEF macro and the SECDEF.H file define a symbolic name for each flag. You construct the flags argument by performing a logical OR operation on the symbol names for all desired flags.
The following table describes each flag that is valid for the $CRMPSC_GFILE_64 service:

Flag Description

SEC$M_CRF Pages are copy-on-reference.

SEC$M_GBL Pages form a global section. By default, this flag is always present in this service and cannot be disabled.

SEC$M_WRT Pages form a read/write section. By default, pages form a read-only section.

SEC$M_DZRO Pages are demand-zero pages. By default, they are not zeroed when copied.
Note that SEC$M_DZRO and SEC$M_CRF cannot both be set and that SEC$M_DZRO set and SEC$M_WRT clear is an invalid combination.

SEC$M_EXPREG Pages are mapped into the first available space at the current end of the specified region.

SEC$M_NO_OVERMAP Pages cannot overmap existing address space. By default, pages can overmap existing address space.

SEC$M_PERM Global section is permanent. By default, global sections are temporary.

SEC$M_SYSGBL Pages form a system global section. By default, pages form a group global section.

All other bits in the flags argument are reserved for future use by Compaq and should be specified as 0. The condition value SS$_IVSECFLG is returned if any undefined bits are set or if an illegal combination of flags is set.
return_va_64

OpenVMS usage: address

type: quadword address

access: write only

mechanism: by 32- or 64-bit reference

The lowest process virtual address into which the global disk file section was mapped. The return_va_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword into which the service returns the virtual address.
Upon successful completion of this service, if the section_offset_64 argument was specified, the virtual address returned in return_va_64 reflects the offset into the global section mapped such that the virtual address returned cannot be aligned on a CPU-specific page boundary. The virtual address returned will always be on an even virtual disk block boundary.
return_length_64

OpenVMS usage: byte count

type: quadword (unsigned)

access: write only

mechanism: by 32- or 64-bit reference

The 32- or 64-bit virtual address of a naturally aligned quadword into which the service returns the length of the virtual address range mapped in bytes.
Upon successful completion of this service, the value in the return_length_64 argument indicates the amount of created address space backed by the section file.
If the number of disk blocks mapped does not represent an exact multiple of CPU-specific pages, the last page in the mapped address space will not be completely mapped by the section file. In this case, modifying memory beyond the amount indicated by return_length_64 can result in the loss of this data.
Unlike the return_length_64 argument for the $CREATE_GFILE service, upon successful completion of this service, the return_length_64 argument does not represent the total length of the global section created if the section_offset_64 argument was specified as nonzero. The value in the section_offset_64 argument plus the value in the return_length_64 argument is the total length of the global disk file section created.
fault_cluster

OpenVMS usage: byte count

type: longword (unsigned)

access: read only

mechanism: by value

Page fault cluster in byte units indicating how many pages are to be brought into memory when a page fault occurs for a single page. The fault cluster specified will be rounded up to a multiple of CPU-specific pages.
If this argument is specified as 0, the system default page fault cluster will be used. If this argument is specified as more than the maximum allowed for the system, no error will be returned. The systemwide maximum will be used.
start_va_64

OpenVMS usage: address

type: quadword address

access: read only

mechanism: by value

The starting virtual address to map the global disk file section. The specified virtual address must be a CPU-specific page aligned address. If the flag SEC$M_EXPREG is specified, this argument will not be used. If SEC$M_EXPREG is clear and the start_va_64 argument is not specified or is specified as 0, the condition value SS$_IVSECFLG will be returned.
Always refer to the return_va_64 and return_length_64 arguments to determine the usable range of virtual addresses mapped.
map_length_64

OpenVMS usage: byte count

type: quadword unsigned

access: read only

mechanism: by value

Length of the global disk file section to be mapped. The length specified must be a multiple of virtual disk blocks. If this argument is not specified as zero, the global disk section is mapped up to and including the last disk block in the section.

Value	Symbolic Name	Match Criteria
0	SEC$K_MATALL	Match all versions of the section.
1	SEC$K_MATEQU	Match only if major and minor identifications match.
2	SEC$K_MATLEQ	Match if the major identifications are equal and the minor identification of the mapper is less than or equal to the minor identification of the global section.

Symbol	Region
VA$C_P0	Program region
VA$C_P1	Control region
VA$C_P2	64-bit program region

Value	Symbolic Name	Access Mode
0	PSL$C_KERNEL	Kernel
1	PSL$C_EXEC	Executive
2	PSL$C_SUPER	Supervisor
3	PSL$C_USER	User

Flag	Description
SEC$M_CRF	Pages are copy-on-reference.
SEC$M_GBL	Pages form a global section. By default, this flag is always present in this service and cannot be disabled.
SEC$M_WRT	Pages form a read/write section. By default, pages form a read-only section.
SEC$M_DZRO	Pages are demand-zero pages. By default, they are not zeroed when copied. Note that SEC$M_DZRO and SEC$M_CRF cannot both be set and that SEC$M_DZRO set and SEC$M_WRT clear is an invalid combination.
SEC$M_EXPREG	Pages are mapped into the first available space at the current end of the specified region.
SEC$M_NO_OVERMAP	Pages cannot overmap existing address space. By default, pages can overmap existing address space.
SEC$M_PERM	Global section is permanent. By default, global sections are temporary.
SEC$M_SYSGBL	Pages form a system global section. By default, pages form a group global section.

Description

The Create and Map Global Disk File Section service allows a process to create and map to a global disk file section. Creating a global disk file section involves defining all or part of a disk file as a section. The section is mapped from a low address to a high address whether the section is mapped in a region that grows from low to high addresses or from high to low addresses. If the $CRMPSC_GFILE_64 service specifies a global disk file section that already exists, the service maps it.
If the condition value SS$_ACCVIO is returned by this service, a value cannot be returned in the memory locations pointed to by the return_va_64 and return_length_64 arguments.
If a condition value other than SS$_ACCVIO is returned, the returned address and returned length indicate the pages that were successfully mapped before the error occurred. If no pages were mapped, the return_va_64 argument will contain the value --1, and a value cannot be returned in the memory location pointed to by the return_length_64 argument.
The flag SEC$M_WRT applies only to the way in which the newly created section is mapped. For a file to be made writable, the channel used to open the file must allow write access to the file.
Required Privileges

To create a global section, the process must have the following privileges:

SYSGBL privilege to create a system global section (if flag SEC$M_SYSGBL is set)
PRMGBL privilege to create a permanent global section

Required Quota

If the section pages are copy-on-reference, the process must have sufficient paging file quota (PGFLQUOTA).
The working set quota (WSQUOTA) of the process must be sufficient to accommodate the increased length of the process page table required by the increase in virtual address space.
Related Services

Previous Next Contents Index

privacy and legal statement

4527PRO_024.HTML

SS$_NORMAL	The service completed successfully. The specified global section already exists and has been mapped.
SS$_CREATED	The service completed successfully. The global section has been created.
SS$_CREATED_SHPT	Global section has been created with shared page tables.
SS$_ACCVIO	The gs_name_64 argument cannot be read by the caller, or the return_va_64 or return_length_64 argument cannot be written by the caller.
SS$_BADRAD	The specified RAD contains no memory, or if the specified RAD is greater than or equal to the maximum number of RADs on the system.
SS$_EXPGFLQUOTA	The process's page file quota is not large enough to accommodate the increased virtual address space.
SS$_GBLSEC_MISMATCH	Global section type mismatch. The specified global section was found; however, it is not a memory-resident section.
SS$_GPTFULL	There is no more room in the system global page table to set up page table entries for the global section or for the shared page tables.
SS$_GSDFULL	There is no more room in the system space allocated to maintain control information for global sections.
SS$_INSFLPGS	Insufficient fluid pages available.
SS$_INSFRPGS	Insufficient free shared pages or private pages.
SS$_INSFWSL	The process's working set limit is not large enough to accommodate the increased virtual address space.
SS$_INV_SHMEM	Shared memory is not valid.
SS$_IVACMODE	The specified access mode is greater than PSL$_USER, or the caller's mode is less privileged than the create mode associated with the region.
SS$_IVLOGNAM	The specified global section name has a length of 0 or has more than 43 characters.
SS$_IVPROTECT	The protection argument format is invalid.
SS$_IVREGID	An invalid region ID was specified.
SS$_IVSECFLG	An invalid flag, a reserved flag, or an invalid combination of flags was specified.
SS$_IVSECIDCTL	The match control field of the global section identification is invalid.
SS$_LEN_NOTPAGMULT	The length_64 argument is not a multiple of CPU-specified pages. Or, if a shared page table region is specified by the region_id_64 argument, the map_length_64 argument is not a multiple of CPU-specific page table pages.
SS$_LOCK_TIMEOUT	An OpenVMS Galaxy lock timed out.
SS$_MRES_PFNSMALL	Preallocated, contiguous, aligned physical memory specified in the Reserved Memory Registry is smaller than the length specified for the memory-resident global section by the length_64 argument.
SS$_NOBREAK	An OpenVMS Galaxy lock is held by another node and was not broken.
SS$_NOMEMRESID	The process attempted to create a memory-resident section, but was not holding the right identifier VMS$MEM_RESIDENT_USER.
SS$_NOPRMGBL	The process does not have the privileges to create or delete a permanent group global section (PRMGBL).
SS$_NOSYSGBL	The process does not have the privileges to create or delete a system global section (SYSGBL).
SS$_OFF_NOTPAGALGN	The section_offset_64 argument is not CPU-specific page aligned. Or, if a shared page table region is specified by the region_id_64 argument, the section_offset_64 argument is not CPU-specific page table page aligned.
SS$_OFFSET_TOO_BIG	The section_offset_64 argument specified is beyond the logical end-of-file.
SS$_PAGNOTINREG	A page in the specified input address range is not within the specified region.
SS$_PAGOWNVIO	A page in the specified input address range is owned by a more privileged access mode.
SS$_REGISFULL	The specified virtual region is full; no space is available in the region for the pages created to contain the mapped section.
SS$_SECREFOVF	The maximum number of references for a global section has been reached (2,147,483,647).
SS$_SECTBLFUL	There are no entries available in the system global section table for the global section or for the shared page tables.
SS$_TOOMANYLNAM	The logical name translation of the gs_name_64 argument exceeded the allowed depth of 10.
SS$_VA_IN_USE	A page in the specified input address range is already mapped and the flag SEC$M_NO_OVERMAP is set, or a page in the specified input address range is in another region, in system space, or inaccessible; or, the existing underlying page cannot be deleted because it is associated with a buffer object.
SS$_VA_NOTPAGALGN	The start_va_64 argument is not CPU-specific page aligned. Or, if a shared page table region is specified by the region_id_64 argument, the start_va_64 argument is not CPU-specific page table page aligned.

OpenVMS usage:	section_name
type:	character-coded text string
access:	read only
mechanism:	by 32- or 64-bit descriptor--fixed-length string descriptor

OpenVMS usage:	section_id
type:	quadword (unsigned)
access:	read only
mechanism:	by 32- or 64-bit reference

OpenVMS usage:	byte offset
type:	quadword (unsigned)
access:	read only
mechanism:	by value

OpenVMS usage:	byte count
type:	quadword (unsigned)
access:	read only
mechanism:	by value

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

OpenVMS usage:	region identifier
type:	quadword (unsigned)
access:	read only
mechanism:	by 64 bit reference

OpenVMS usage:	access_mode
type:	longword (unsigned)
access:	read only
mechanism:	by value

OpenVMS usage:	mask_longword
type:	longword (unsigned)
access:	read only
mechanism:	by value

OpenVMS usage:	address
type:	quadword address
access:	write only
mechanism:	by 32- or 64-bit reference