pnode: lift peers() into pnode.h

it's going to be useful both in pnode.c and namespace.c

Reviewed-by: Christian Brauner <[email protected]>
Signed-off-by: Al Viro <[email protected]>

Author: Al Viro

fs/pnode.c

@@ -216,11 +216,6 @@ static struct mount *next_group(struct mount *m, struct mount *origin)
 static struct mount *last_dest, *first_source, *last_source, *dest_master;
 static struct hlist_head *list;
 
-static inline bool peers(const struct mount *m1, const struct mount *m2)
-{
-	return m1->mnt_group_id == m2->mnt_group_id && m1->mnt_group_id;
-}
-
 static int propagate_one(struct mount *m, struct mountpoint *dest_mp)
 {
 	struct mount *child;

fs/pnode.h

@@ -34,6 +34,11 @@ static inline void set_mnt_shared(struct mount *mnt)
 	mnt->mnt.mnt_flags |= MNT_SHARED;
 }
 
+static inline bool peers(const struct mount *m1, const struct mount *m2)
+{
+	return m1->mnt_group_id == m2->mnt_group_id && m1->mnt_group_id;
+}
+
 void change_mnt_propagation(struct mount *, int);
 int propagate_mnt(struct mount *, struct mountpoint *, struct mount *,
 		struct hlist_head *);