configfs: Convert subsystem semaphore to mutex

Convert the su_sem member of struct configfs_subsystem to a struct
mutex, as that's what it is. Also convert all the users and update
Documentation/configfs.txt and Documentation/configfs_example.c
accordingly.

[ Conflict in fs/dlm/config.c with commit
  3168b0780d06ace875696f8a648d04d6089654e5 manually resolved. --Mark ]

Inspired-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

3 files changed, 14 insertions, 14 deletions

diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index 5e6e37e58f36..d3b1dbb9b5b8 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -562,7 +562,7 @@ static int populate_groups(struct config_group *group)
 
 /*
  * All of link_obj/unlink_obj/link_group/unlink_group require that
- * subsys->su_sem is held.
+ * subsys->su_mutex is held.
  */
 
 static void unlink_obj(struct config_item *item)
@@ -783,7 +783,7 @@ static int configfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 
         snprintf(name, dentry->d_name.len + 1, "%s", dentry->d_name.name);
 
-        down(&subsys->su_sem);
+        mutex_lock(&subsys->su_mutex);
         group = NULL;
         item = NULL;
         if (type->ct_group_ops->make_group) {
@@ -797,7 +797,7 @@ static int configfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
                 if (item)
                         link_obj(parent_item, item);
         }
-        up(&subsys->su_sem);
+        mutex_unlock(&subsys->su_mutex);
 
         kfree(name);
         if (!item) {
@@ -841,13 +841,13 @@ static int configfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 out_unlink:
         if (ret) {
                 /* Tear down everything we built up */
-                down(&subsys->su_sem);
+                mutex_lock(&subsys->su_mutex);
                 if (group)
                         unlink_group(group);
                 else
                         unlink_obj(item);
                 client_drop_item(parent_item, item);
-                up(&subsys->su_sem);
+                mutex_unlock(&subsys->su_mutex);
 
                 if (module_got)
                         module_put(owner);
@@ -910,17 +910,17 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry)
         if (sd->s_type & CONFIGFS_USET_DIR) {
                 configfs_detach_group(item);
 
-                down(&subsys->su_sem);
+                mutex_lock(&subsys->su_mutex);
                 unlink_group(to_config_group(item));
         } else {
                 configfs_detach_item(item);
 
-                down(&subsys->su_sem);
+                mutex_lock(&subsys->su_mutex);
                 unlink_obj(item);
         }
 
         client_drop_item(parent_item, item);
-        up(&subsys->su_sem);
+        mutex_unlock(&subsys->su_mutex);
 
         /* Drop our reference from above */
         config_item_put(item);
diff --git a/fs/dlm/config.c b/fs/dlm/config.c
index 4348cb42cf17..2f8e3c81bc19 100644
--- a/fs/dlm/config.c
+++ b/fs/dlm/config.c
@@ -607,7 +607,7 @@ static struct clusters clusters_root = {
 int dlm_config_init(void)
 {
         config_group_init(&clusters_root.subsys.su_group);
-        init_MUTEX(&clusters_root.subsys.su_sem);
+        mutex_init(&clusters_root.subsys.su_mutex);
         return configfs_register_subsystem(&clusters_root.subsys);
 }
 
@@ -751,9 +751,9 @@ static struct space *get_space(char *name)
         if (!space_list)
                 return NULL;
 
-        down(&space_list->cg_subsys->su_sem);
+        mutex_lock(&space_list->cg_subsys->su_mutex);
         i = config_group_find_item(space_list, name);
-        up(&space_list->cg_subsys->su_sem);
+        mutex_unlock(&space_list->cg_subsys->su_mutex);
 
         return to_space(i);
 }
@@ -772,7 +772,7 @@ static struct comm *get_comm(int nodeid, struct sockaddr_storage *addr)
         if (!comm_list)
                 return NULL;
 
-        down(&clusters_root.subsys.su_sem);
+        mutex_lock(&clusters_root.subsys.su_mutex);
 
         list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
                 cm = to_comm(i);
@@ -792,7 +792,7 @@ static struct comm *get_comm(int nodeid, struct sockaddr_storage *addr)
                         break;
                 }
         }
-        up(&clusters_root.subsys.su_sem);
+        mutex_unlock(&clusters_root.subsys.su_mutex);
 
         if (!found)
                 cm = NULL;
diff --git a/fs/ocfs2/cluster/nodemanager.c b/fs/ocfs2/cluster/nodemanager.c
index 9f5ad0f01ce0..48b77d113cb2 100644
--- a/fs/ocfs2/cluster/nodemanager.c
+++ b/fs/ocfs2/cluster/nodemanager.c
@@ -934,7 +934,7 @@ static int __init init_o2nm(void)
                 goto out_sysctl;
 
         config_group_init(&o2nm_cluster_group.cs_subsys.su_group);
-        init_MUTEX(&o2nm_cluster_group.cs_subsys.su_sem);
+        mutex_init(&o2nm_cluster_group.cs_subsys.su_mutex);
         ret = configfs_register_subsystem(&o2nm_cluster_group.cs_subsys);
         if (ret) {
                 printk(KERN_ERR "nodemanager: Registration returned %d\n", ret);