REQUEST=SHAREMEMOBJ requests that the address space be given access to one or more specified shared memory objects.
The requirements for the caller are:
Environmental factor | Requirement |
---|---|
Minimum authorization: | The caller must be running in supervisor state or with PSW key 0-7. |
Dispatchable unit mode: | Task or SRB |
Cross memory mode: | Any PASN, any HASN, any SASN. |
AMODE: | 31- or 64-bit |
ASC mode: | Primary or access register (AR) |
Interrupt status: | Enabled for I/O and external interrupts |
Locks: | When a local lock is held for a request the lock must be for the address space specified (or defaulted) by the input ALETVALUE. |
Control parameters: | Control parameters must be in the primary address space and can reside both below and above the bar. |
None.
This macro supports multiple versions. Some keywords are unique to certain versions. See PLISTVER parameter description.
Before issuing the IARV64 macro, the caller does not have to place any information into any register unless using it in register notation for a particular parameter, or using it as a base register.
Some callers depend on register contents remaining the same before and after issuing a service. If the system changes the contents of registers on which the caller depends, the caller must save them before issuing the service, and restore them after the system returns control.
None
The REQUEST=SHAREMEMOBJ option of the IARV64 macro is written as follows:
Syntax | Description |
---|---|
name | name: symbol. Begin name in column 1. |
␢ | One or more blanks must precede IARV64. |
IARV64 | |
␢ | One or more blanks must follow IARV64. |
REQUEST=SHAREMEMOBJ | |
,USERTKN=usertkn | usertkn: RS-type address or address in register (2) - (12). |
,RANGLIST=ranglist | ranglist: RS-type address or address in register (2) - (12). |
,NUMRANGE=numrange | numrange: RS-type address or address in register (2) - (12). |
,NUMRANGE=1 | Default: NUMRANGE=1 |
,ALETVALUE=aletvalue | aletvalue: RS-type address or address in register (2) - (12). |
,ALETVALUE=0 | Default: ALETVALUE=0 |
,SVCDUMPRGN=YES | Default: SVCDUMPRGN=YES |
,DUMPPRIORITY=dumppriority | |
,SVCDUMPRGN=NO | |
,COND=NO | Default: COND=NO |
,COND=YES | |
,RETCODE=retcode | retcode: RS-type address or register (2) - (12). |
,RSNCODE=rsncode | rsncode: RS-type address or register (2) - (12). |
,PLISTVER=IMPLIED_VERSION | Default: PLISTVER=IMPLIED_VERSION |
,PLISTVER=MAX | |
,PLISTVER=0, 1, 2, 3 or 4 | |
,MF=S | Default: MF=S |
,MF=(L,list addr) | list addr: RS-type address or register (1) - (12). |
,MF=(L,list addr,attr) | |
,MF=(L,list addr,0D) | |
,MF=(E,list addr) | |
,MF=(E,list addr,COMPLETE) |
|
The parameters are explained as follows:
To avoid inadvertent collisions in the values specified, the left word (bits 0-31) should represent an address of some storage related to the caller. The system enforces the rule that the left word is non-zero for authorized callers. The right word should represent the virtual address of some storage related to the caller, which could be a control block address, an entry point address, etc.; the choice of which to use is made by the application.
To code: Specify the RS-type address, or address in register (2)-(12), of a required doubleword field that identifies the user token to be associated with the shared memory object.
The length of this field is 8 bytes.
The length of this field is 8 bytes.
To code: Specify the RS-type address, or address in register (2)-(12), of an eight-byte pointer field.
To code: Specify the RS-type address, or address in register (2)-(12), of a fullword field.
The only supported values are 0 (primary) and 2 (home). The ALETVALUE parameter can be used only by callers running in supervisor state or with PSW key 0-7. The default is 0.
To code: Specify the RS-type address, or address in register (2)-(12), of a fullword field.
To code: Specify the RS-type address of a fullword field, or register (2)-(12).
To code: Specify the RS-type address of a fullword field, or register (2)-(12).
If you can tolerate the size change, IBM® recommends that you always specify PLISTVER=MAX on the list form of the macro. Specifying MAX ensures that the list-form parameter list is always long enough to hold all the parameters you might specify on the execute form, when both are assembled with the same level of the system. In this way, MAX ensures that the parameter list does not overwrite nearby storage.
Use MF=S to specify the standard form of the macro, which builds an inline parameter list and generates the macro invocation to transfer control to the service. MF=S is the default.
Use MF=L to specify the list form of the macro. Use the list form together with the execute form of the macro for applications that require reentrant code. The list form defines an area of storage that the execute form uses to store the parameters. Only the PLISTVER parameter may be coded with the list form of the macro.
Use MF=E to specify the execute form of the macro. Use the execute form together with the list form of the macro for applications that require reentrant code. The execute form of the macro stores the parameters into the storage area defined by the list form, and generates the macro invocation to transfer control to the service.