Generating inline code

This form of MODESET is used to ensure that storage areas and the control program functions they are associated with have the same protection key. The EXTKEY parameter of MODESET indicates the key to be set in the current PSW.

You can set the following keys:

Key of zero
Key of TCB
Key of caller of type 1 SVC issuing MODESET
Key of caller of type 2, 3, or 4 SVC issuing MODESET

Other parameters of MODESET allow the original key to be saved and restored upon completion of the desired changes. The inline form of the MODESET macro does not result in a change to the caller’s PSW Key Mask.