target: simplify the target template registration API

Instead of calling target_fabric_configfs_init() +
target_fabric_configfs_register() / target_fabric_configfs_deregister()
target_fabric_configfs_free() from every target driver, rewrite the API
so that we have simple register/unregister functions that operate on
a const operations vector.

This patch also fixes a memory leak in several target drivers. Several
target drivers namely called target_fabric_configfs_deregister()
without calling target_fabric_configfs_free().

A large part of this patch is based on earlier changes from
Bart Van Assche <bart.vanassche@sandisk.com>.

(v2: Add a new TF_CIT_SETUP_DRV macro so that the core configfs code
can declare attributes as either core only or for drivers)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

3 files changed, 23 insertions, 11 deletions

diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 71699cf3cc71..383110d608a0 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -519,7 +519,7 @@ struct se_cmd {
         struct list_head        se_cmd_list;
         struct completion       cmd_wait_comp;
         struct kref             cmd_kref;
-        struct target_core_fabric_ops *se_tfo;
+        const struct target_core_fabric_ops *se_tfo;
         sense_reason_t          (*execute_cmd)(struct se_cmd *);
         sense_reason_t          (*execute_rw)(struct se_cmd *, struct scatterlist *,
                                               u32, enum dma_data_direction);
@@ -890,7 +890,7 @@ struct se_portal_group {
         /* List of TCM sessions associated wth this TPG */
         struct list_head        tpg_sess_list;
         /* Pointer to $FABRIC_MOD dependent code */
-        struct target_core_fabric_ops *se_tpg_tfo;
+        const struct target_core_fabric_ops *se_tpg_tfo;
         struct se_wwn           *se_tpg_wwn;
         struct config_group     tpg_group;
         struct config_group     *tpg_default_groups[7];
diff --git a/include/target/target_core_configfs.h b/include/target/target_core_configfs.h
index e0801386e4dc..25bb04c4209e 100644
--- a/include/target/target_core_configfs.h
+++ b/include/target/target_core_configfs.h
@@ -5,12 +5,6 @@
 #define TARGET_CORE_NAME_MAX_LEN        64
 #define TARGET_FABRIC_NAME_SIZE         32
 
-extern struct target_fabric_configfs *target_fabric_configfs_init(
-                                struct module *, const char *);
-extern void target_fabric_configfs_free(struct target_fabric_configfs *);
-extern int target_fabric_configfs_register(struct target_fabric_configfs *);
-extern void target_fabric_configfs_deregister(struct target_fabric_configfs *);
-
 struct target_fabric_configfs_template {
         struct config_item_type tfc_discovery_cit;
         struct config_item_type tfc_wwn_cit;
diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h
index c93cfdf0d8e5..17c7f5ac7ea0 100644
--- a/include/target/target_core_fabric.h
+++ b/include/target/target_core_fabric.h
@@ -2,6 +2,8 @@
 #define TARGET_CORE_FABRIC_H
 
 struct target_core_fabric_ops {
+        struct module *module;
+        const char *name;
         struct configfs_subsystem *tf_subsys;
         char *(*get_fabric_name)(void);
         u8 (*get_fabric_proto_ident)(struct se_portal_group *);
@@ -90,8 +92,23 @@ struct target_core_fabric_ops {
         struct se_node_acl *(*fabric_make_nodeacl)(struct se_portal_group *,
                                 struct config_group *, const char *);
         void (*fabric_drop_nodeacl)(struct se_node_acl *);
+
+        struct configfs_attribute **tfc_discovery_attrs;
+        struct configfs_attribute **tfc_wwn_attrs;
+        struct configfs_attribute **tfc_tpg_base_attrs;
+        struct configfs_attribute **tfc_tpg_np_base_attrs;
+        struct configfs_attribute **tfc_tpg_attrib_attrs;
+        struct configfs_attribute **tfc_tpg_auth_attrs;
+        struct configfs_attribute **tfc_tpg_param_attrs;
+        struct configfs_attribute **tfc_tpg_nacl_base_attrs;
+        struct configfs_attribute **tfc_tpg_nacl_attrib_attrs;
+        struct configfs_attribute **tfc_tpg_nacl_auth_attrs;
+        struct configfs_attribute **tfc_tpg_nacl_param_attrs;
 };
 
+int target_register_template(const struct target_core_fabric_ops *fo);
+void target_unregister_template(const struct target_core_fabric_ops *fo);
+
 struct se_session *transport_init_session(enum target_prot_op);
 int transport_alloc_session_tags(struct se_session *, unsigned int,
                 unsigned int);
@@ -110,7 +127,8 @@ void	transport_deregister_session_configfs(struct se_session *);
 void    transport_deregister_session(struct se_session *);
 
 
-void    transport_init_se_cmd(struct se_cmd *, struct target_core_fabric_ops *,
+void    transport_init_se_cmd(struct se_cmd *,
+                const struct target_core_fabric_ops *,
                 struct se_session *, u32, int, int, unsigned char *);
 sense_reason_t transport_lookup_cmd_lun(struct se_cmd *, u32);
 sense_reason_t target_setup_cmd_from_cdb(struct se_cmd *, unsigned char *);
@@ -162,8 +180,8 @@ int	core_tpg_set_initiator_node_queue_depth(struct se_portal_group *,
                 unsigned char *, u32, int);
 int     core_tpg_set_initiator_node_tag(struct se_portal_group *,
                 struct se_node_acl *, const char *);
-int     core_tpg_register(struct target_core_fabric_ops *, struct se_wwn *,
-                struct se_portal_group *, void *, int);
+int     core_tpg_register(const struct target_core_fabric_ops *,
+                struct se_wwn *, struct se_portal_group *, void *, int);
 int     core_tpg_deregister(struct se_portal_group *);
 
 /* SAS helpers */