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Locks a range of pages in the working set; if the pages are not already in the working set, it brings them in and locks them. A page locked in the working set does not become a candidate for replacement.
SYS$LKWSET inadr ,[retadr] ,[acmode]
int sys$lkwset (struct _va_range *inadr, struct _va_range *retadr, unsigned int acmode);
inadr
OpenVMS usage: address_range type: longword (unsigned) access: read only mechanism: by reference
Starting and ending virtual addresses of the range of pages to be locked in the working set. The inadr argument is the address of a 2-longword array containing, in order, the starting and ending process virtual addresses. Only the virtual page number portion of each virtual address is used; the low-order byte-within-page bits are ignored.On VAX systems, if the starting and ending virtual addresses are the same, a single page is locked.
On Alpha and I64 systems, if the first address in the 2-longword array is within an image mapped to your process, the entire image specified by the address is locked in the working set.
Be sure to check calls to the SYS$LKWSET and SYS$LKWSET_64 system services for correct arguments. This affects only process-based code running above IPL2. Compiler and linker differences might cause your program layout to change from Alpha, resulting in incorrectly calculated starting and ending addresses for calls to SYS$LKWSET and SYS$LKWSET_64. Calling these services with incorrect arguments and then executing this code above IPL2 could cause PGFIPLHI bugchecks. Note that SYS$LKWSET and SYS$LKWSET_64 automatically lock linker-generated short data sections associated with code sections locked in the working set.
retadr
OpenVMS usage: address_range type: longword (unsigned) access: write only mechanism: by reference
Starting and ending process virtual addresses of the range of pages actually locked by $LKWSET. The retadr argument is the address of a 2-longword array containing, in order, the starting and ending process virtual addresses.On Alpha and I64 systems, if the inadr argument specifies an address within an image mapped to your process, retadr specifies only one range of pages locked in the working set. Many ranges of pages might be locked.
acmode
OpenVMS usage: access_mode type: longword (unsigned) access: read only mechanism: by value
Access mode to be associated with the pages to be locked. The acmode argument is a longword containing the access mode. The $PSLDEF macro defines the four access modes.The most privileged access mode used is the access mode of the caller. For the $LKWSET service to complete successfully, the resultant access mode must be equal to or more privileged than the access mode already associated with the pages to be locked.
The Lock Pages in Working Set service locks a range of pages in the working set; if the pages are not already in the working set, it brings them in and locks them. A page locked in the working set does not become a candidate for replacement.If more than one page is being locked and you need to determine specifically which pages were previously locked, the pages should be locked one at a time.
If an error occurs while the $LKWSET service is locking pages, the return array, if requested, indicates the pages that were successfully locked before the error occurred. If no pages are locked, both longwords in the return address array contain the value --1.
Global pages with write access cannot be locked into the working set.
On Alpha and I64 systems, if the first address specified to SYS$LKWSET is within an image mapped to your process, a success status indicates that the entire image containing the specified address is locked in the working set. This behavior helps to ensure that privileged processes entering kernel mode and raising IPL higher than IPL 2 do not access an invalid page and cause a PGFIPLHI bugcheck. The system keeps a count of the number of times each image within your process is locked in the working set. This count is maintained so that calls to SYS$ULWSET unlock the image only when it has been called the same number of times as SYS$LKWSET.
If an attempt to lock an image in the working set returns SS$_LKWSETFUL, you might consider moving all kernel mode code within the image to a separate, smaller sharable image. Otherwise, you might consider increasing the working set quota of the process.
The LIBRTL routine LIB$LOCK_IMAGE and LIB$UNLOCK_IMAGE are preferable to SYS$LKWSET and SYS$ULKWSET for locking code and related data in the working set. For more information about locking images in the working set, see the LIBRTL manual and the descriptions of LIB$LOCK_IMAGE and LIB$UNLOCK_IMAGE.
None
None
You can unlock pages locked in the working set with the Unlock Page from Working Set ($ULWSET) service.
For more information, see the chapter on memory management in the HP OpenVMS Programming Concepts Manual.
SS$_WASCLR The service completed successfully. All of the specified pages were previously unlocked. The entire image might have been locked in the working set. SS$_WASSET The service completed successfully. At least one of the specified pages was previously locked in the working set. If the image has been locked in the working set, the count of times the image has been locked in the working set has been incremented. SS$_ACCVIO The input address array cannot be read; the output address array cannot be written; a page in the specified range is inaccessible or nonexistent; or an attempt was made to lock pages by a caller whose access mode is less privileged than the access mode associated with the pages. SS$_LKWSETFUL The locked working set is full. If any more pages are locked, not enough dynamic pages will be available to continue execution. If the image is being locked in the working set, the image is too large to be entirely locked in the working set. SS$_NOPRIV A page in the specified range is in the system address space, or a global page with write access was specified. SS$_PAGOWNVIO The pages could not be locked because the access mode associated with the call to $LKWSET was less privileged than the access mode associated with the pages that were to be locked.
On Alpha and I64 systems, locks a range of virtual addresses in the working set. If the pages are not already in the working set, the service brings them in and locks them. A page locked in the working set does not become a candidate for replacement.This service accepts 64-bit addresses.
SYS$LKWSET_64 start_va_64 ,length_64 ,acmode ,return_va_64 ,return_length_64
int sys$lkwset_64 (void *start_va_64, unsigned __int64 length_64, unsigned int acmode, void *(*(return_va_64)), unsigned __int64 *return_length_64);
start_va_64
OpenVMS usage: address type: quadword address access: read only mechanism: by value
The starting virtual address of the pages to be locked in the working set. The specified virtual address will be rounded down to a CPU-specific page boundary.length_64
OpenVMS usage: byte count type: quadword (unsigned) access: read only mechanism: by value
Length of the virtual address space to be locked in the working set. The specified length will be rounded up to a CPU-specific page boundary so that it includes all CPU-specific pages in the requested range.acmode
OpenVMS usage: access_mode type: longword (unsigned) access: read only mechanism: by value
Access mode associated with the pages to be locked. 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. For the $LKWSET_64 service to complete successfully, the resultant access mode must be equal to or more privileged than the access mode already associated with the pages to be locked.
return_va_64
OpenVMS usage: address type: quadword address access: write only mechanism: by 32- or 64-bit reference
The lowest process virtual address of the pages locked in the working set. The return_va_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword into which the service returns the virtual address.return_length_64
OpenVMS usage: byte count type: quadword (unsigned) access: write only mechanism: by 32- or 64-bit reference
The length of the virtual address range locked in the working set. The return_length_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword into which the service returns the length of the virtual address range in bytes.
The Lock Pages in Working Set service locks a range of pages in the working set; if the pages are not already in the working set, it brings them in and locks them. A page locked in the working set does not become a candidate for replacement.If the condition value SS$_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$_ACCVIO is returned, the returned address and returned length indicate the pages that were successfully locked before the error occurred. If no pages were locked, the return_va_64 argument will contain the value -1, and a value cannot be returned in the memory location pointed to by the return_length_64 argument.
Global pages with write access cannot be locked into the working set.
Be sure to check calls to the SYS$LKWSET and SYS$LKWSET_64 system services for correct arguments. This affects only process-based code running above IPL2. Compiler and linker differences might cause your program layout to change from Alpha, resulting in incorrectly calculated starting and ending addresses for calls to SYS$LKWSET and SYS$LKWSET_64. Calling these services with incorrect arguments and then executing this code above IPL2 could cause PGFIPLHI bugchecks. Note that SYS$LKWSET and SYS$LKWSET_64 automatically lock linker-generated short data sections associated with code sections locked in the working set.
On Alpha and I64 systems, if the first address specified to SYS$LKWSET_64 is within an image mapped to your process, a success status indicates that the entire image containing the specified address is locked in the working set. This behavior helps to ensure that privileged processes entering kernel mode and raising IPL higher than IPL 2 do not access an invalid page and cause a PGFIPLHI bugcheck. The system keeps a count of the number of times each image within your process is locked in the working set. This count is maintained so that calls to SYS$ULWSET_64 unlock the image only when it has been called the same number of times as SYS$LKWSET_64.
If an attempt to lock an image in the working set returns SS$_LKWSETFUL, you might consider moving all kernel mode code within the image to a separate, smaller sharable image. Otherwise, you might consider increasing the working set quota of the process.
The LIBRTL routine LIB$LOCK_IMAGE and LIB$UNLOCK_IMAGE are preferable to SYS$LKWSET_64 and SYS$ULKWSET_64 for locking code and related data in the working set. For more information about locking images in the working set, see the LIBRTL manual and the descriptions of LIB$LOCK_IMAGE and LIB$UNLOCK_IMAGE.
None
None
$LKWSET, $ULWSET, $ULWSET_64
SS$_WASCLR The service completed successfully. All of the specified pages were previously unlocked. The entire image might have been locked in the working set. SS$_WASSET The service completed successfully. At least one of the specified pages was previously locked in the working set. If the image has been locked in the working set, the count of times the image has been locked in the working set has been incremented. SS$_ACCVIO The return_va_64 or return_length_64 argument cannot be written by the caller, or an attempt was made to lock pages by a caller whose access mode is less privileged than the access mode associated with the pages. SS$_LKWSETFUL The locked working set is full. If any more pages are locked, not enough dynamic pages will be available to continue execution. If the image is being locked in the working set, the image is too large to be entirely locked in the working set. SS$_NOPRIV No privilege; global pages with write access cannot be locked into the working set. SS$_PAGNOTINREG A page in the specified range is not within the specified region. SS$_PAGOWNVIO The pages could not be locked because the access mode associated with the call to $LKWSET_64 was less privileged than the access mode associated with the pages that were to be locked.
Establishes a correspondence between pages (maps) in the virtual address space of the process and physical pages occupied by a global section.
SYS$MGBLSC inadr ,[retadr] ,[acmode] ,[flags] ,gsdnam ,[ident] ,[relpag]
int sys$mgblsc (struct _va_range *inadr, struct _va_range *retadr, unsigned int acmode, unsigned int flags, void *gsdnam, struct _secid *ident, unsigned int relpag);
inadr
OpenVMS usage: address_range type: longword (unsigned) access: read only mechanism: by reference
Starting and ending virtual addresses into which the section is to be mapped. The inadr argument is the address of a 2-longword array containing, in order, the starting and ending process virtual addresses. Only the virtual page number portion of each virtual address is used to specify which pages are to be mapped; the low-order byte-within-page bits are ignored for this purpose.The interpretation of the inadr argument depends on the setting of SEC$M_EXPREG in the flags argument and on whether you are using an Alpha, an I64, or a VAX system. These system types are discussed separately in this section.
On Alpha and I64 systems, if you do not set the SEC$M_EXPREG flag, the inadr argument specifies the starting and ending virtual addresses of the region to be mapped. Addresses in system space are not allowed. The addresses must be aligned on CPU-specific pages; no rounding to CPU-specific pages occurs. The lower address of the inadr argument must be on a CPU-specific page boundary and the higher address of the inadr argument must be 1 less than a CPU-specific boundary, thus forming a range, from lowest to highest, of address bytes. You can use the SYI$_PAGE_SIZE item code in the $GETSYI system service to set the inadr argument to the proper values. You do this to avoid programming errors that might arise because of incorrect programming assumptions about page sizes.
If, on the other hand, you do set the SEC$M_EXPREG flag, indicating that the mapping should take place using the first available space in a particular region, the inadr argument is used only to indicate the desired region: the program region (P0) or the control region (P1).
Caution
Mapping into the P1 region is generally discouraged, but, if done, must be executed with extreme care. Since the user stack is mapped in P1, it is possible that references to the user stack might inadvertently read or write the pages mapped with $CRMPSC.When the SEC$M_EXPREG flag is set, the second inadr longword is ignored, while bit 30 (the second most significant bit) of the first inadr longword is used to determine the region of choice. If the bit is clear, P0 is chosen; if the bit is set, P1 is chosen. On Alpha and I64 systems, bit 31 (the most significant bit) of the first inadr longword must be 0. To ensure compatibility between VAX and Alpha or I64 systems when you choose a region, HP recommends that you specify, for the first inadr longword, any virtual address in the desired region.
On VAX systems, if you do not set the SEC$M_EXPREG flag, the inadr argument specifies the starting and ending virtual addresses of the region to be mapped. Addresses in system space are not allowed. If the starting and ending virtual addresses are the same, a single page is mapped.
Note
If the SEC$M_EXPREG flag is not set, HP recommends that the inadr argument always specify the entire virtual address range, from starting byte address to ending byte address. This ensures compatibility between VAX and Alpha or I64 systems.If, on the other hand, you do set the SEC$M_EXPREG flag, indicating that the mapping should take place using the first available space in a particular region, the inadr argument is used only to indicate the desired region: the program region (P0) or the control region (P1).
Caution
Mapping into the P1 region is generally discouraged, but, if done, must be executed with extreme care. Since the user stack is mapped in P1, it is possible that references to the user stack might inadvertently read or write the pages mapped with $CRMPSC.When the SEC$M_EXPREG flag is set, the second inadr longword is ignored, while bit 30 (the second most significant bit) of the first inadr longword is used to determine the region of choice. If the bit is clear, P0 is chosen; if the bit is set, P1 is chosen. On VAX systems, bit 31 (the most significant bit) of the first inadr longword is ignored. To ensure compatibility between VAX and Alpha or I64 systems when you choose a region, HP recommends that you specify, for the first inadr longword, any virtual address in the desired region.
retadr
OpenVMS usage: address_range type: longword (unsigned) access: write only mechanism: by reference
Starting and ending process virtual addresses into which the section was actually mapped by $MGBLSC. The retadr argument is the address of a 2-longword array containing, in order, the starting and ending process virtual addresses.On Alpha and I64 systems, the retadr argument returns the starting and ending addresses of the usable range of addresses. This might differ from the total amount mapped. The retadr argument is required when the relpag argument is specified. If the section being mapped does not completely fill the last page used to map the section, the retadr argument indicates the highest address that actually maps the section. If the relpag argument is used to specify an offset into the section, the retadr argument reflects the offset.
acmode
OpenVMS usage: access_mode type: longword (unsigned) access: read only mechanism: by value
Access mode to be associated with the pages mapped into the process virtual address space. The acmode argument is a longword containing the access mode. The $PSLDEF macro defines symbols for the four access modes.The most privileged access mode used is the access mode of the caller.
flags
OpenVMS usage: mask_longword type: longword (unsigned) access: read only mechanism: by value
Flag mask specifying options for the operation. The flags argument is a longword bit vector wherein a bit when set specifies the corresponding option.The $SECDEF macro defines symbolic names for the flag bits. You construct the flags argument by specifying the symbolic names of each desired option in a logical OR operation.
The following table describes each flag option:
Flag Option Description SEC$M_WRT Map the section with read/write access. By default, the section is mapped with read-only access. If SEC$M_WRT is specified and the section is not copy-on-reference, write access is required. SEC$M_SYSGBL Map a system global section. By default, the section is a group global section. SEC$M_EXPREG Map the section into the first available virtual address range. By default, the section is mapped into the range specified by the inadr argument. See the inadr argument description for a complete explanation of how to set the SEC$M_EXPREG flag.
SEC$M_UNCACHED Flag that must be set when a PFN-mapped section is created if this section must be treated as uncached memory. Flag is ignored on Alpha systems; it applies only to I64 systems. gsdnam
OpenVMS usage: section_name type: character-coded text string access: read only mechanism: by descriptor--fixed-length string descriptor
Name of the global section. The gsdnam argument is the address of a character string descriptor pointing to this name string.For group global sections, the operating system interprets the group UIC as part of the global section name; thus, the names of global sections are unique to UIC groups. Further, all global section names are implicitly qualified by their identification fields.
You can specify any name from 1 to 43 characters. All processes mapping to the same global section must specify the same name. Note that the name is case sensitive.
Use of characters valid in logical names is strongly encouraged. Valid values include alphanumeric characters, the dollar sign ($), and the underscore (_). If the name string begins with an underscore (_), the underscore is stripped and the resultant string is considered to be the actual name. Use of the colon (:) is not permitted.
Names are first subject to a logical name translation, after the application of the prefix GBL$ to the name. If the result translates, it is used as the name of the section. If the resulting name does not translate, the name specified by the caller is used as the name of the section.
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