tree ef8948240b0aff2a366136a8303afc70e6c84da8
parent 72d31053f62c4bc464c2783974926969614a8649
author Tejun Heo <tj@kernel.org> 1222291343 -0500
committer Eric Van Hensbergen <ericvh@ericvh-desktop.austin.ibm.com> 1222291343 -0500

9p: implement proper trans module refcounting and unregistration

9p trans modules aren't refcounted nor were they unregistered
properly.  Fix it.

* Add 9p_trans_module->owner and reference the module on each trans
  instance creation and put it on destruction.

* Protect v9fs_trans_list with a spinlock.  This isn't strictly
  necessary as the list is manipulated only during module loading /
  unloading but it's a good idea to make the API safe.

* Unregister trans modules when the corresponding module is being
  unloaded.

* While at it, kill unnecessary EXPORT_SYMBOL on p9_trans_fd_init().

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>