amd64_round_page
dump_avail_off = AMD64_PAGE_SIZE + amd64_round_page(vmst->hdr.msgbufsize);
off = dump_avail_off + amd64_round_page(vmst->hdr.dumpavailsize);
sparse_off = off + amd64_round_page(vmst->hdr.bitmapsize) +
amd64_round_page(vmst->hdr.pmapsize);
off += amd64_round_page(vmst->hdr.bitmapsize);
off += amd64_round_page(vmst->hdr.pmapsize);