target: Add se_sess->sess_kref + get/put helpers

This patch adds basic se_session->sess_kref and get/put helpers for fabric
session reference counting.  It sets the initial kref in transport_init_session()
and adds a target_release_session() callback to invoke TFO->close_session()
for final session shutdown.

Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Joern Engel <joern@logfs.org>
Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

2 files changed, 3 insertions, 0 deletions

diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 1641dea0c282..d63079409eff 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -654,6 +654,7 @@ struct se_session {
         struct list_head        sess_cmd_list;
         struct list_head        sess_wait_list;
         spinlock_t              sess_cmd_lock;
+        struct kref             sess_kref;
 };
 
 struct se_device;
diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h
index e5d8c47892b7..7e76aa167009 100644
--- a/include/target/target_core_fabric.h
+++ b/include/target/target_core_fabric.h
@@ -105,6 +105,8 @@ void	__transport_register_session(struct se_portal_group *,
                 struct se_node_acl *, struct se_session *, void *);
 void    transport_register_session(struct se_portal_group *,
                 struct se_node_acl *, struct se_session *, void *);
+void    target_get_session(struct se_session *);
+int     target_put_session(struct se_session *);
 void    transport_free_session(struct se_session *);
 void    transport_deregister_session_configfs(struct se_session *);
 void    transport_deregister_session(struct se_session *);