Invoke the entry point

To invoke the entry point you have chosen, use the following instructions:

LR 15,0
BALR 14,15

The output returns are:

Return code
Reason code (possibly)
Delimiter page

When control returns to the caller, the GPRs contain:

Register: Contents
0: The reason code if R15 is 08.
1: The address of the parameter list
2-14: Unchanged
15: The return code

When control returns to the caller, the ARs are unchanged.

When the IARQDxx entry point returns control to your program, GPR 15 contains the return code. If the return code is 8, GPR0 contains the reason code.

Table 1. Return and Reason Codes for IARQD
Return Code	Reason Code	Meaning
00	none	A copy of the page cannot be found in virtual storage. (that is: real storage, expanded storage, or auxiliary storage) This could happen because: The page was not obtained through the GETMAIN or STORAGE macro The page was just obtained and has no data in it yet The page cannot be read into real storage due to an I/O error
04	none	All copies of the page are in virtual storage at the same level as what is on permanent storage. This return code is only possible for pages that have been mapped through the DIV (data-in-virtual) macro.
08	xx0000xx	The page is in central storage. At least one copy of the page has been found in virtual storage. For data-in-virtual (DIV) pages, the copy of the page is at a later level than the copy on permanent storage.
08	xx0004xx	The page is on a synchronous medium, such as in expanded storage At least one copy of the page has been found in virtual storage. For data-in-virtual (DIV) pages, the copy of the page is at a later level than the copy on permanent storage.
08	xx0008xx	The page is on an asynchronous medium At least one copy of the page has been found in virtual storage. For data-in-virtual (DIV) pages, the copy of the page is at a later level than the copy on permanent storage.
0C		The status of the page is not determined