mips_user_cachectl
int mips_user_cachectl(struct proc *, vaddr_t, size_t, int);
error = mips_user_cachectl(p, ccua.va, ccua.nbytes, ccua.ctl);
error = mips_user_cachectl(p, ccua.va, ccua.nbytes, ccua.ctl);
return mips_user_cachectl(p, va, nbytes, cacheop);