Copyright Digital Equipment Corp. All rights reserved.
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:
Symbolic
Value 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.
prot
OpenVMS usage:file_protection
type: longword (unsigned)
access: read only
mechanism: by value
Protection to be applied to the global page file section.
The mask contains four 4-bit fields. Bits are read from right to
left in each field.
To view the mask diagram, see the VSI OpenVMS System Services
Reference Manual.
Cleared bits indicate that read, write, execute, and delete
access, in that order, are granted to the particular category
of user. Only read, write, and execute access are meaningful
for section protection. Delete access bits are ignored. Read
access also grants execute access for those situations where
execute access applies. If zero is specified, read access and
write access are granted to all users.
start_pfn
OpenVMS usage:page frame number
type: longword (unsigned) on Alpha, quadword (unsigned)
on Integrity servers
access: read only
mechanism: by value
The CPU-specific page frame number where the section begins.
page_count
OpenVMS usage:CPU-specific page count
type: longword (unsigned) on Alpha, quadword (unsigned)
on Integrity servers
access: read only
mechanism: by value
Length of the page frame section in CPU-specific pages.
region_id_64
OpenVMS usage:region identifier
type: quadword (unsigned)
access: read only
mechanism: by 32- or 64-bit reference
The region ID associated with the region to map the global page
frame 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.
relative_page
OpenVMS usage:CPU-specific page number
type: longword (unsigned)
access: read only
mechanism: by value
Relative CPU-specific page number within the global section to
start mapping.
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
$CRMPSC_GPFN_64:
Flag Description
SEC$M_ARGS64 Indicates that all parameters, specifically start_
pfn and page_count, are passed as 64-bit numbers.
This flag is ignored on OpenVMS Alpha but must be
set on Integrity server systems. If the flag is
not set on Integrity servers, the error code SS$_
IVSECFLG is returned.
SEC$M_EXPREG Pages are mapped into the first available space at
the current end of the specified region.
SEC$M_GBL Pages form a global section. By default, this flag
is always present in this service and cannot be
disabled.
SEC$M_PERM Global section is permanent. By default, this flag
is always present in this service and cannot be
disabled.
SEC$M_PFNMAP Pages form a page frame section. By default, this
flag is always present in this service and cannot
be disabled.
SEC$M_NO_ Pages cannot overmap existing address space. By
OVERMAP default, pages can overmap existing address space.
SEC$M_SYSGBL Pages form a system global section. By default,
pages form a group global section.
SEC$M_ Flag that must be set when a PFN-mapped section
UNCACHED is created if this section must be treated as
uncached memory. Flag is ignored on Alpha systems;
it applies only to Integrity server systems.
SEC$M_WRT Pages form a read/write section. By default, pages
form a read-only section.
All other bits in the flags argument are reserved for future
use by VSI and should be specified as 0. The condition value
SS$_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 page
frame section was mapped. The return_va_64 argument is the 32-
or 64-bit address of a naturally aligned quadword into which the
service returns the virtual address.
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.
start_va_64
OpenVMS usage:address
type: quadword address
access: read only
mechanism: by value
The starting virtual address to map the global page frame
section. The specified virtual address must be a CPU-specific
page-aligned address. If the flag SEC$M_EXPREG is specified, the
start_va_64 argument must not be specified or must be specified
as 0. If SEC$M_EXPREG is set and the start_va_64 argument is
nonzero, the condition value SS$_IVSECFLG is returned.
Always refer to the return_va_64 and return_length_64 arguments
to determine the range of virtual addresses mapped.
map_page_count
OpenVMS usage:CPU-specific page count
type: longword (unsigned)
access: read only
mechanism: by value
Length of the global page frame section to be mapped in CPU-
specific pages.