Man pages matching name hugetlbfs_unlinked_fd in section 3:

hugetlbfs_unlinked_fd.3.en	debian 10 / libhugetlbfs-dev
hugetlbfs_unlinked_fd.3.en	debian 11 / libhugetlbfs-dev
hugetlbfs_unlinked_fd.3.en	debian 12 / libhugetlbfs-dev