PKMAP_NR          191 mm/highmem.c   	pkmap_count[PKMAP_NR(vaddr)]++;
PKMAP_NR          192 mm/highmem.c   	BUG_ON(pkmap_count[PKMAP_NR(vaddr)] < 2);
PKMAP_NR          212 mm/highmem.c   	nr = PKMAP_NR(vaddr);