ALPHA_L2SEG_SIZE
alpha_trunc_l2seg(sva) + ALPHA_L2SEG_SIZE;
l2eva = alpha_trunc_l2seg(sva) + ALPHA_L2SEG_SIZE;
va += ALPHA_L2SEG_SIZE;
#define alpha_trunc_l2seg(x) (((u_long)(x)) & ~(ALPHA_L2SEG_SIZE-1))