1 files changed, 19 insertions, 2 deletions

diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h
index 321ed84ad4ce..d2c439db4efa 100644
--- a/include/linux/kernfs.h
+++ b/include/linux/kernfs.h
@@ -111,12 +111,27 @@ struct kernfs_node {
         struct kernfs_iattrs    *iattr;
 };
 
+/*
+ * kernfs_dir_ops may be specified on kernfs_create_root() to support
+ * directory manipulation syscalls.  These optional callbacks are invoked
+ * on the matching syscalls and can perform any kernfs operations which
+ * don't necessarily have to be the exact operation requested.
+ */
+struct kernfs_dir_ops {
+        int (*mkdir)(struct kernfs_node *parent, const char *name,
+                     umode_t mode);
+        int (*rmdir)(struct kernfs_node *kn);
+        int (*rename)(struct kernfs_node *kn, struct kernfs_node *new_parent,
+                      const char *new_name);
+};
+
 struct kernfs_root {
         /* published fields */
         struct kernfs_node      *kn;
 
         /* private fields, do not use outside kernfs proper */
         struct ida              ino_ida;
+        struct kernfs_dir_ops   *dir_ops;
 };
 
 struct kernfs_open_file {
@@ -206,7 +221,8 @@ struct kernfs_node *kernfs_find_and_get_ns(struct kernfs_node *parent,
 void kernfs_get(struct kernfs_node *kn);
 void kernfs_put(struct kernfs_node *kn);
 
-struct kernfs_root *kernfs_create_root(void *priv);
+struct kernfs_root *kernfs_create_root(struct kernfs_dir_ops *kdops,
+                                       void *priv);
 void kernfs_destroy_root(struct kernfs_root *root);
 
 struct kernfs_node *kernfs_create_dir_ns(struct kernfs_node *parent,
@@ -255,7 +271,8 @@ kernfs_find_and_get_ns(struct kernfs_node *parent, const char *name,
 static inline void kernfs_get(struct kernfs_node *kn) { }
 static inline void kernfs_put(struct kernfs_node *kn) { }
 
-static inline struct kernfs_root *kernfs_create_root(void *priv)
+static inline struct kernfs_root *
+kernfs_create_root(struct kernfs_dir_ops *kdops, void *priv)
 { return ERR_PTR(-ENOSYS); }
 
 static inline void kernfs_destroy_root(struct kernfs_root *root) { }