[PATCH 6/8] mnt: Use generic ns_common::count

[Kirill Tkhai <ktkhai@virtuozzo.com>]

Convert mount namespace to use generic counter.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
---
 fs/mount.h     |    3 +--
 fs/namespace.c |    4 ++--
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/mount.h b/fs/mount.h
index c3e0bb6e5782..f296862032ec 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -7,7 +7,6 @@
 #include <linux/watch_queue.h>
 
 struct mnt_namespace {
-	atomic_t		count;
 	struct ns_common	ns;
 	struct mount *	root;
 	/*
@@ -130,7 +129,7 @@ static inline void detach_mounts(struct dentry *dentry)
 
 static inline void get_mnt_ns(struct mnt_namespace *ns)
 {
-	atomic_inc(&ns->count);
+	refcount_inc(&ns->ns.count);
 }
 
 extern seqlock_t mount_lock;
diff --git a/fs/namespace.c b/fs/namespace.c
index 31c387794fbd..8c39810e6ec3 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -3296,7 +3296,7 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns, bool a
 	new_ns->ns.ops = &mntns_operations;
 	if (!anon)
 		new_ns->seq = atomic64_add_return(1, &mnt_ns_seq);
-	atomic_set(&new_ns->count, 1);
+	refcount_set(&new_ns->ns.count, 1);
 	INIT_LIST_HEAD(&new_ns->list);
 	init_waitqueue_head(&new_ns->poll);
 	spin_lock_init(&new_ns->ns_lock);
@@ -3870,7 +3870,7 @@ void __init mnt_init(void)
 
 void put_mnt_ns(struct mnt_namespace *ns)
 {
-	if (!atomic_dec_and_test(&ns->count))
+	if (!refcount_dec_and_test(&ns->ns.count))
 		return;
 	drop_collected_mounts(&ns->root->mnt);
 	free_mnt_ns(ns);