KPF_COMPOUND_HEAD
u |= kpf_copy_bit(k, KPF_COMPOUND_HEAD, PG_head);
[KPF_COMPOUND_HEAD] = "H:compound_head",
if (!(page_flags & (KPF_COMPOUND_HEAD | KPF_COMPOUND_TAIL))) {
if (page_flags & KPF_COMPOUND_HEAD)
(page_flags & KPF_COMPOUND_HEAD) ||
!(page_flags & (KPF_COMPOUND_HEAD | KPF_COMPOUND_TAIL))) {
const uint64_t folio_head_flags = KPF_THP | KPF_COMPOUND_HEAD;