uvm_swap_decrypt_pages
uvm_swap_decrypt_pages(swslot, bp->b_data, npages);
uvm_swap_decrypt_pages(ctx->swslot, bp->b_data,
uvm_swap_decrypt_pages(startslot, (void *)kva, npages);
void uvm_swap_decrypt_pages(int startslot, void *p, int npages);