ofw_claimvirt
if (ofw_claimvirt(va, size) == -1) {
systempage.pv_va = ofw_claimvirt(vector_page, PAGE_SIZE, 0);
ofw_claimvirt(va, size, 0); /* make sure OFW knows about the memory */
if (ofw_claimvirt(va, alloc_size, 0) != va)
static vaddr_t ofw_claimvirt(vaddr_t, vsize_t, vaddr_t);