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>

1 files changed, 13 insertions, 36 deletions

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 6e0a477681e9..07015389ee5a 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -93,7 +93,7 @@ MODULE_PARM_DESC(srpt_service_guid,
                  " instead of using the node_guid of the first HCA.");
 
 static struct ib_client srpt_client;
-static struct target_fabric_configfs *srpt_target;
+static const struct target_core_fabric_ops srpt_template;
 static void srpt_release_channel(struct srpt_rdma_ch *ch);
 static int srpt_queue_status(struct se_cmd *cmd);
 
@@ -3851,7 +3851,7 @@ static struct se_portal_group *srpt_make_tpg(struct se_wwn *wwn,
         int res;
 
         /* Initialize sport->port_wwn and sport->port_tpg_1 */
-        res = core_tpg_register(&srpt_target->tf_ops, &sport->port_wwn,
+        res = core_tpg_register(&srpt_template, &sport->port_wwn,
                         &sport->port_tpg_1, sport, TRANSPORT_TPG_TYPE_NORMAL);
         if (res)
                 return ERR_PTR(res);
@@ -3919,7 +3919,9 @@ static struct configfs_attribute *srpt_wwn_attrs[] = {
         NULL,
 };
 
-static struct target_core_fabric_ops srpt_template = {
+static const struct target_core_fabric_ops srpt_template = {
+        .module                         = THIS_MODULE,
+        .name                           = "srpt",
         .get_fabric_name                = srpt_get_fabric_name,
         .get_fabric_proto_ident         = srpt_get_fabric_proto_ident,
         .tpg_get_wwn                    = srpt_get_fabric_wwn,
@@ -3964,6 +3966,10 @@ static struct target_core_fabric_ops srpt_template = {
         .fabric_drop_np                 = NULL,
         .fabric_make_nodeacl            = srpt_make_nodeacl,
         .fabric_drop_nodeacl            = srpt_drop_nodeacl,
+
+        .tfc_wwn_attrs                  = srpt_wwn_attrs,
+        .tfc_tpg_base_attrs             = srpt_tpg_attrs,
+        .tfc_tpg_attrib_attrs           = srpt_tpg_attrib_attrs,
 };
 
 /**
@@ -3994,33 +4000,9 @@ static int __init srpt_init_module(void)
                 goto out;
         }
 
-        srpt_target = target_fabric_configfs_init(THIS_MODULE, "srpt");
-        if (IS_ERR(srpt_target)) {
-                printk(KERN_ERR "couldn't register\n");
-                ret = PTR_ERR(srpt_target);
+        ret = target_register_template(&srpt_template);
+        if (ret)
                 goto out;
-        }
-
-        srpt_target->tf_ops = srpt_template;
-
-        /*
-         * Set up default attribute lists.
-         */
-        srpt_target->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = srpt_wwn_attrs;
-        srpt_target->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = srpt_tpg_attrs;
-        srpt_target->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = srpt_tpg_attrib_attrs;
-        srpt_target->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
-        srpt_target->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
-        srpt_target->tf_cit_tmpl.tfc_tpg_nacl_base_cit.ct_attrs = NULL;
-        srpt_target->tf_cit_tmpl.tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
-        srpt_target->tf_cit_tmpl.tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
-        srpt_target->tf_cit_tmpl.tfc_tpg_nacl_param_cit.ct_attrs = NULL;
-
-        ret = target_fabric_configfs_register(srpt_target);
-        if (ret < 0) {
-                printk(KERN_ERR "couldn't register\n");
-                goto out_free_target;
-        }
 
         ret = ib_register_client(&srpt_client);
         if (ret) {
@@ -4031,11 +4013,7 @@ static int __init srpt_init_module(void)
         return 0;
 
 out_unregister_target:
-        target_fabric_configfs_deregister(srpt_target);
-        srpt_target = NULL;
-out_free_target:
-        if (srpt_target)
-                target_fabric_configfs_free(srpt_target);
+        target_unregister_template(&srpt_template);
 out:
         return ret;
 }
@@ -4043,8 +4021,7 @@ out:
 static void __exit srpt_cleanup_module(void)
 {
         ib_unregister_client(&srpt_client);
-        target_fabric_configfs_deregister(srpt_target);
-        srpt_target = NULL;
+        target_unregister_template(&srpt_template);
 }
 
 module_init(srpt_init_module);