set_memory_valid
set_memory_valid(addr, 1, !protect);
int set_memory_valid(unsigned long addr, int numpages, int enable);
set_memory_valid(addr, 1, !protect);
int set_memory_valid(unsigned long addr, int numpages, int enable);
return set_memory_valid(addr, nr, valid);
set_memory_valid((unsigned long)page_address(page), numpages, enable);