title: Where has init_MUTEX gone in linux kernel version 3.2?
body: <p>I am following the <em>Linux Device Drivers (3rd edition)</em>. When I try to imitate the <em>scull</em> example in chapter 6 , an error is reported. It says that:</p>
  
  <pre><code>    error: implicit declaration of function ‘init_MUTEX’ [-Werror=implicit-function-declaration]
  </code></pre>
  
  <p>Can anyone tell me where has init_MUTEX gone?
  By the way, Is there a list that I can check all the kernel API changes?</p>