Restrict access of admin uploads to certain logged-in users?

You can use current_user_has_role for this

And if the standard roles are not enough for you, then I would suggest to download the Members plugin by Justin Tadlock which enables you to add roles.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)