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Allocates an OpenVMS Galaxy lock block from a lock table created with the $CREATE_GALAXY_LOCK_TABLE service.Note that this system service is supported only in an OpenVMS Alpha Galaxy environment.
For more information about programming with OpenVMS Galaxy system services, see the HP OpenVMS Alpha Partitioning and Galaxy Guide.
SYS$CREATE_GALAXY_LOCK lcktbl_handle ,name ,size ,timeout ,ipl ,rank ,handle
int sys$create_galaxy_lock (unsigned int lcktbl_handle, void *name, unsigned int size, unsigned int timeout, unsigned int ipl, unsigned int rank, unsigned __int64 *lock_handle);
lcktbl_handle
OpenVMS usage: lock table handle type: longword (unsigned) access: read mechanism: input by value
The 32-bit lock table handle that identifies the lock table in which to create the lock. This value is returned by SYS$CREATE_GALAXY_LOCK_TABLE.name
OpenVMS usage: address type: ASCID string access: read mechanism: input by reference
The name parameter is a pointer to an ASCID string (passed by descriptor). The name can be a maximum of 15 characters. Lock names are not checked for uniqueness; therefore, multiple locks can be created with the same name.timeout
OpenVMS usage: wait timeout type: longword (unsigned) access: read mechanism: input by value
The 32-bit wait or spin timeout specified in 10 microsecond units. If not specified, the timeout defaults to 10 microseconds.size
OpenVMS usage: byte count type: longword (unsigned) access: read mechanism: input by value
The size of the galaxy lock in bytes. Galaxy locks have two legal sizes. These values are returned by SYS$GET_GALAXY_LOCK_SIZE. The value passed to SYS$CREATE_GALAXY_LOCK must be equal to the value passed to the call to SYS$CREATE_GALAXY_LOCK_TABLE.ipl
OpenVMS usage: IPL of lock type: longword (unsigned) access: read mechanism: input by value
For galaxy locks acquired in kernel mode, the IPL to raise to while the lock is held. This parameter is ignored for all other access mode.rank
OpenVMS usage: rank of lock type: longword (unsigned) access: read mechanism: input by value
Rank applied to a galaxy lock. Ranking is used to detect potential deadlocks. This parameter is currently ignored.handle
OpenVMS usage: address type: quadword (unsigned) access: write mechanism: output by reference
The handle parameter is a pointer to a quadword. The value returned is a 64-bit handle that uniquely identifies the lock galaxy-wide.
This service allocates an OpenVMS Galaxy lock block from a lock table created with the $CREATE_GALAXY_LOCK_TABLE service.For System Lock: CMKRNL, SHMEM
For User Lock: SHMEM
Write access to Lock TableNone
$ACQUIRE_GALAXY_LOCK, $CREATE_GALAXY_LOCK_TABLE, $DELETE_GALAXY_LOCK, $DELETE_GALAXY_LOCK_TABLE, $GET_GALAXY_LOCK_INFO, $GET_GALAXY_LOCK_SIZE, $RELEASE_GALAXY_LOCK
SS$_NORMAL Normal completion. SS$_ACCVIO Access violation on parameter. SS$_BADLCKTBL OpenVMS Galaxy lock table is corrupt. SS$_BADPARAM Bad parameter value. SS$_IVLOCKID Invalid lock id. SS$_IVLOCKTBL Invalid lock table. SS$_INSFMEM Insufficient memory in lock table. SS$_NOCMKRNL Operation requires CMKRNL privilege. SS$_NOSHMEM Operation requires SHMEM privilege.
Allocates an OpenVMS Galaxy lock table.Note that this system service is supported only in an OpenVMS Alpha Galaxy environment.
For more information about programming with OpenVMS Galaxy system services, see the HP OpenVMS Alpha Partitioning and Galaxy Guide.
SYS$CREATE_GALAXY_LOCK_TABLE name ,accmode ,section_size ,section_type ,prot ,lock_size ,lcktbl_handle
int sys$create_galaxy_lock_table (void *name, unsigned int accmode, unsigned __int64 section_size, unsigned int section_type, unsigned int prot, unsigned int lock_size, unsigned int *lcktbl_handle);
name
OpenVMS usage: address type: ASCID string access: read mechanism: input by reference
The name parameter is a pointer to an ASCID string (passed by descriptor). The name is given to the global section that is created to contain the galaxy locks.accmode
OpenVMS usage: access mode type: longword (unsigned) access: read mechanism: input by value
Access mode that is to be the owner of the pages created during the mapping. The accmode argument is a longword containing the access mode.section_size
OpenVMS usage: byte count type: quadword (unsigned) access: read mechanism: input by value
Length of the global section to be created, in bytes. The size must be specified as a multiple of the CPU-specific page size. A size of zero is illegal.section_type
OpenVMS usage: bit mask type: longword (unsigned) access: read mechanism: input by value
Used to control where in virtual memory the global section is created. If GLCKTBL$C_PROCESS is specified, the section is created in P2 (process) space. If GLCKTBL$C_SYSTEM is specified, the section is created in S0/S1 (system) space. These constants are defined in the GLOCKDEF macro.prot
OpenVMS usage: protection type: longword (unsigned) access: read mechanism: input by value
Protection to be applied to the global section.The mask contains four 4-bit fields. Bits are read from right to left in each field. The following diagram depicts the mask:
Cleared bits indicate that read, write, execute, and delete access, in that order, are granted to the particular category of user.
Only read and write access are meaningful for lock section protection. Delete access bits are ignored.
| OpenVMS usage: | byte count |
| type: | longword (unsigned) |
| access: | read |
| mechanism: | input by value |
| OpenVMS usage: | address |
| type: | longword |
| access: | write |
| mechanism: | output by reference |
This service allocates an OpenVMS Galaxy lock table. This structure is used to maintain information about a shared memory section, which this service also creates. The first caller of the service with a unique lock table name creates the section. Additional callers map it. This shared memory section contains a set of Galaxy locks. All locks residing in the section are of the same size. Once the lock table is created, the $CREATE_GALAXY_LOCK service can be used to create and allocate a lock from the table.The flags GLCKTBL$C_PROCESS and GLCKTBL$C_SYSTEM specify whether the shared memory region is mapped into system space or process space. Creation of process space sections requires the SHMEM privilege. Creation of system space sections requires the SHMEM and CMKRNL privileges.
CMKRNL, SHMEM
None
$ACQUIRE_GALAXY_LOCK, $CREATE_GALAXY_LOCK, $DELETE_GALAXY_LOCK, $DELETE_GALAXY_LOCK_TABLE, $GET_GALAXY_LOCK_INFO, $GET_GALAXY_LOCK_SIZE, $RELEASE_GALAXY_LOCK
SS$_NORMAL Normal completion. SS$_ACCVIO Access violation on parameter. SS$_BADPARAM Bad parameter value. SS$_CREATED File or section did not exist; has been created. SS$_IVLOCKID Invalid lock id. SS$_NOPRIV No privilege for attempted operation. SS$_NOCMKRNL Operation requires CMKRNL privilege. SS$_NOSHMEM Operation requires SHMEM privilege.
On Alpha and I64 systems, creates a permanent, memory-resident, global demand-zero section to which processes can map. Shared page table sections can also be created.This service accepts 64-bit addresses.
SYS$CREATE_GDZRO gs_name_64 ,ident_64 ,prot ,length_64 ,acmode ,flags [,reserved_length_64] [,rad_mask]
int sys$create_gdzro (void *gs_name_64, struct _secid *ident_64, unsigned int prot, unsigned __int64 length_64, unsigned int acmode, unsigned int flags,...);
gs_name_64
OpenVMS usage: section_name type: character-coded text string access: read only mechanism: by 32- or 64-bit descriptor--fixed-length string descriptor
Name of the global section. The gs_name_64 argument is the 32- or 64-bit virtual address of a naturally aligned 32- or 64-bit string descriptor pointing to this name string.ident_64
OpenVMS usage: section_id type: quadword (unsigned) access: read only mechanism: by 32- or 64-bit reference
Identification value specifying the version number of the global section. The ident_64 argument is a quadword containing three fields. The ident_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword that contains the identification value.The first longword specifies the matching criteria in its low-order 2 bits. Their meanings are as follows:
Value Symbolic Name Match Criteria 0 SEC$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. 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 demand-zero section. The mask contains four 4-bit fields. Bits are read from right to left in each field. The following diagram depicts the mask:
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 0 is specified, read access and write access are granted to all users.
| OpenVMS usage: | byte count |
| type: | quadword (unsigned) |
| access: | read only |
| mechanism: | by value |
Creating a memory-resident global section with shared page tables does not imply that the global section must have a length that is an even multiple of CPU-specific page table pages. The global section might not fully use the last shared page table page. |
| OpenVMS usage: | access_mode |
| type: | longword (unsigned) |
| access: | read only |
| mechanism: | by value |
If the memory-resident global section is created with shared page tables, this is the access mode that is stored in the owner, read, and write fields of the corresponding shared page table entries (PTEs).
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 |
| OpenVMS usage: | mask_longword |
| type: | longword (unsigned) |
| access: | read only |
| mechanism: | by value |
The following table describes the flags that are valid for the $CREATE_GDZRO service:
| Flag | Description |
|---|---|
| SEC$M_DZRO | Pages are demand-zero pages. By default, this flag is always present in this service and cannot be disabled. |
| SEC$M_GBL | Pages form a global section. By default, this flag is always present in this service and cannot be disabled. |
| SEC$M_MRES | Pages form a memory-resident 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_RAD_HINT | When set, the argument rad_mask is used as a mask of RADs from which to allocate memory. See the rad_mask argument description for more information. |
| SEC$M_READ_ONLY_SHPT | Create shared table pages for the section that allow read access only. |
| SEC$M_SHMGS | Create a shared-memory global section. |
| SEC$M_SYSGBL | Pages form a system global section. By default, pages form a group global section. |
| SEC$M_WRT | Pages form a read/write section. By default, this flag is always present in this service and cannot be disabled. |
All other bits in the flags argument are reserved for future use by HP and should be specified as 0. The condition value SS$_IVSECFLG is returned if any undefined bits are set.
| OpenVMS usage: | byte count |
| type: | quadword (unsigned) |
| access: | write only |
| mechanism: | 32- or 64-bit reference |
If reserved_length_64 is not specified or is specified as 0, no reserved length is returned to the caller.
If the memory-resident global section is not registered, reserved_length_64 is written with the value 0.
| OpenVMS usage: | mask_quadword |
| type: | quadword (unsigned) |
| access: | read only |
| mechanism: | by value |
The rad_mask argument is considered only if the SEC$M_RAD_HINT flag is specified. Otherwise, this argument is ignored.
On a system that does not support resource affinity domains (RADs), specifying 1 for the rad_mask argument is allowed.
Note: OpenVMS support for RADs is available only on the AlphaServer GS series systems. For more information about using RADs, see the HP OpenVMS Alpha Partitioning and Galaxy Guide.
The Create Permanent Global Demand-Zero Section service allows a process to create a permanent, memory-resident, global demand-zero section. If you set the SEC$M_SHMGS flag, the section is created as a Galaxy-wide global demand-zero section in shared memory.You must call either the $CREATE_GDZRO service or the $CRMPSC_GDZRO_64 service on each instance where the Galaxy shared memory will be accessed.
Memory-resident or Galaxy-wide global sections contain demand-zero allocation pages that are writable and memory resident. All pages in these types of global section are shared by all processes that map to the global section.
The pages are always resident in memory and are not backed up by any file on any disk. The pages are not placed into the process's working set list when the process maps to the global section and the virtual memory is referenced by the process. The pages are also not charged against the process's working set quota or against any page-file quota.
To create a memory-resident section, the process must have the rights identifier, VMS$MEM_RESIDENT_USER. The error status, SS$_NOMEMRESID, is returned if the caller has not been granted this identifier. To create a Galaxy-wide shared section, the process must have the SHMEM privilege.
Only memory-resident sections can be registered with the Reserved Memory Registry in the SYSMAN facility. Memory for Galaxy-wide shared sections is reserved through appropriate settings of the console environment parameters.
If the section is not registered in the Reserved Memory Registry, or if the /NOALLOCATE qualifier was specified when the global section was registered in the Reserved Memory Registry, invalid global PTEs are written to the global page table. When the global section is mapped, invalid page table entries are placed in the process page table. Physical memory is not allocated until the pages are referenced.
If the global section is registered in the Reserved Memory Registry, the size of the global section need not match the reserved size. If the global section is not registered in the Reserved Memory Registry, or if the reserved size is smaller than the size of the global section, the error status SS$_INSFLPGS is returned if there are not enough fluid pages in the system to satisfy the request.
If the /ALLOCATE qualifier was specified when the global section was registered in the Reserved Memory Registry, contiguous, aligned, physical pages are preallocated during system initialization for this global section. Valid page table entries are placed in the global page table and when the global section is mapped, valid page table entries are placed in the process page table. With the proper virtual alignment, granularity hints (GH) are used to map to the global pages.
If the global section is not registered in the Reserved Memory Registry, or if the /PAGE_TABLES qualifier was specified when the global section was registered, shared page tables are created for the memory-resident global section.
If the /ALLOCATE and /PAGE_TABLE qualifiers were specified when the global section was registered in the Reserved Memory Registry, contiguous, aligned physical pages are preallocated during system initialization for this global section, and granularity hints are used to map to the shared page table sections.
The following table lists the factors affecting the creation of shared page tables for memory-resident global sections. The /ALLOCATE and the /PAGE_TABLES qualifiers pertain to the Reserved Memory Registry command RESERVED_MEMORY ADD entered for the memory-resident global section being created. For more information about using the SYSMAN utility to create entries to the Reserved Memory Registry, see the HP OpenVMS System Management Utilities Reference Manual.
/ALLOCATE /PAGE_TABLES Outcome Not registered Not registered Shared page tables created. Shared page tables cannot use GH.
Returns SS$_CREATED_SHPT.
No No No shared page tables created. Returns SS$_CREATED.
No Yes Shared page tables created. Shared page tables cannot use GH.
Returns SS$CREATED_SHPT.
Yes No No shared page tables created. Returns SS$_CREATED.
Yes Yes Shared page tables created. Shared page tables can use GH.
Returns SS$_CREATED_SHPT.
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