VOID
CdSetThreadContext(
  IN  PIRP_CONTEXT IrpContext,
  IN  PTHREAD_CONTEXT ThreadContext
  );

Routine Description:

    This routine is called at each Fsd/Fsp entry point set up the IrpContext
    and thread local storage to track top level requests.  If there is
    not a Cdfs context in the thread local storage then we use the input one.
    Otherwise we use the one already there.  This routine also updates the
    IrpContext based on the state of the top-level context.

    If the TOP_LEVEL flag in the IrpContext is already set when we are called
    then we force this request to appear top level.

Arguments:

    ThreadContext - Address on stack for local storage if not already present.

    ForceTopLevel - We force this request to appear top level regardless of
        any previous stack value.

Return Value:

    None