configfs: accessing item hierarchy during rmdir(2)

Add a notification callback, ops->disconnect_notify(). It has the same
prototype as ->drop_item(), but it will be called just before the item
linkage is broken. This way, configfs users who want to do work while
the object is still in the heirarchy have a chance.

Client drivers will still need to config_item_put() in their
->drop_item(), if they implement it.  They need do nothing in
->disconnect_notify().  They don't have to provide it if they don't
care.  But someone who wants to be notified before ci_parent is set to
NULL can now be notified.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/configfs.h b/include/linux/configfs.h
index 5ce0fc4..8227e73 100644
--- a/include/linux/configfs.h
+++ b/include/linux/configfs.h
@@ -169,6 +169,7 @@ struct configfs_group_operations {
 	struct config_item *(*make_item)(struct config_group *group, const char *name);
 	struct config_group *(*make_group)(struct config_group *group, const char *name);
 	int (*commit_item)(struct config_item *item);
+	void (*disconnect_notify)(struct config_group *group, struct config_item *item);
 	void (*drop_item)(struct config_group *group, struct config_item *item);
 };