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

From: Kirill Tkhai
Date: Mon Aug 03 2020 - 06:16:48 EST


Convert mount namespace to use generic counter.

Signed-off-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
---
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);