- user context, then you can use a simple semaphore
- (<filename>linux/linux/semaphore.h</filename>) to protect it. This
- is the most trivial case: you initialize the semaphore to the number
- of resources available (usually 1), and call
- <function>down_interruptible()</function> to grab the semaphore, and
- <function>up()</function> to release it. There is also a
- <function>down()</function>, which should be avoided, because it
+ user context, then you can use a simple mutex
+ (<filename>include/linux/mutex.h</filename>) to protect it. This
+ is the most trivial case: you initialize the mutex. Then you can
+ call <function>mutex_lock_interruptible()</function> to grab the mutex,
+ and <function>mutex_unlock()</function> to release it. There is also a
+ <function>mutex_lock()</function>, which should be avoided, because it