uvm_pmr_freepages
uvm_pmr_freepages(&seg->pgs[seg->avail_start - seg->start],
uvm_pmr_freepages(&pgs[avail_start - start],
uvm_pmr_freepages(pg, 1);
uvm_pmr_freepages(pg, 1);
void uvm_pmr_freepages(struct vm_page *, psize_t);