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>
diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
index cdf137a..6a32ffd 100644
--- a/net/9p/trans_fd.c
+++ b/net/9p/trans_fd.c
@@ -1629,6 +1629,7 @@
.maxsize = MAX_SOCK_BUF,
.def = 1,
.create = p9_trans_create_tcp,
+ .owner = THIS_MODULE,
};
static struct p9_trans_module p9_unix_trans = {
@@ -1636,6 +1637,7 @@
.maxsize = MAX_SOCK_BUF,
.def = 0,
.create = p9_trans_create_unix,
+ .owner = THIS_MODULE,
};
static struct p9_trans_module p9_fd_trans = {
@@ -1643,6 +1645,7 @@
.maxsize = MAX_SOCK_BUF,
.def = 0,
.create = p9_trans_create_fd,
+ .owner = THIS_MODULE,
};
int p9_trans_fd_init(void)
@@ -1659,4 +1662,10 @@
return 0;
}
-EXPORT_SYMBOL(p9_trans_fd_init);
+
+void p9_trans_fd_exit(void)
+{
+ v9fs_unregister_trans(&p9_tcp_trans);
+ v9fs_unregister_trans(&p9_unix_trans);
+ v9fs_unregister_trans(&p9_fd_trans);
+}