The check (intval < PAGE_SIZE) will involve type cast, so even when
specifying negative value to rsize/wsize/readdir_max_bytes, it will
pass the validation check successfully.
Signed-off-by: NChengguang Xu <cgxu519@gmx.com>
Reviewed-by: NIlya Dryomov <idryomov@gmail.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>