FOLL_NOWAIT
foll |= f->attempt_pfault ? FOLL_NOWAIT : 0;
foll &= ~FOLL_NOWAIT;
foll |= FOLL_NOWAIT;
foll &= ~FOLL_NOWAIT;
if (WARN_ON_ONCE(unlikely(gup_flags & FOLL_NOWAIT)))
if (flags & FOLL_NOWAIT)
if (WARN_ON_ONCE(pages_done == 0 && !(flags & FOLL_NOWAIT)))
if ((kfp->flags & FOLL_NOWAIT) &&