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NAME : HCPBITMP
DESCRIPTION: Bit Map Control Block
DSECT : BITMP
FUNCTION : The Bit Map Control Block contains fields that control
access to the bits, pointers to the bits, and other
useful stuff.
LOCATED BY : R2 at entry to HCPBIT routines points to a full
word that points to the BITMP.
CREATED BY : HCPBIT
DELETED BY : HCPBITRL
REFERENCES : None
SERIALIZED : Changes to the contents of bit maps need not be done
under the control of the BITMP lock, because
Compare-and-Swap is used to change the bits and the
pointers to the bits. However, if serialization is
needed, the users of the bit maps should call the
HCPBIT entry points AS, AX, RS, RX, SX, etc., which
call the analogous HCPLCK entry points for control
over the BITMP lock.
RELOCATION CONSIDERATIONS : This control block is relocated as part of a live
guest relocation (LGR). The bits and fields that
need to be relocated are defined in the
corresponding LGRBITMP COPY file. Whenever changes
are made to this control block, consideration must
be given to any effects these changes will have on
a relocation. If any new fields or bits are
defined, they may need to be relocated. If
existing bits or fields are changed, corresponding
modifications may be required in the LGR version of
this control block. Consider also the effects of
these changes on a relocation involving a back-level
release of CP.
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