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>
This commit is contained in:
Tejun Heo
2008-09-24 16:22:23 -05:00
committed by Eric Van Hensbergen
parent 72d31053f6
commit 72029fe85d
6 changed files with 95 additions and 30 deletions

View File

@@ -75,7 +75,6 @@ static int parse_opts(char *opts, struct p9_client *clnt)
int option;
int ret = 0;
clnt->trans_mod = v9fs_default_trans();
clnt->dotu = 1;
clnt->msize = 8192;
@@ -108,7 +107,7 @@ static int parse_opts(char *opts, struct p9_client *clnt)
clnt->msize = option;
break;
case Opt_trans:
clnt->trans_mod = v9fs_match_trans(&args[0]);
clnt->trans_mod = v9fs_get_trans_by_name(&args[0]);
break;
case Opt_legacy:
clnt->dotu = 0;
@@ -117,6 +116,10 @@ static int parse_opts(char *opts, struct p9_client *clnt)
continue;
}
}
if (!clnt->trans_mod)
clnt->trans_mod = v9fs_get_default_trans();
kfree(options);
return ret;
}
@@ -150,6 +153,7 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
if (!clnt)
return ERR_PTR(-ENOMEM);
clnt->trans_mod = NULL;
clnt->trans = NULL;
spin_lock_init(&clnt->lock);
INIT_LIST_HEAD(&clnt->fidlist);
@@ -235,6 +239,8 @@ void p9_client_destroy(struct p9_client *clnt)
clnt->trans = NULL;
}
v9fs_put_trans(clnt->trans_mod);
list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist)
p9_fid_destroy(fid);