target: Correct transport_wait_for_tasks() documentation

[mirror_ubuntu-bionic-kernel.git] / drivers / target / target_core_transport.c

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 1cadc9eefa21a47e783160b874dbd2ce02f8f05f..62a50ea52a49ab5f9dbd48dea8e9b1953895f8cb 100644 (file)
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -457,8 +457,20 @@ static void target_complete_nacl(struct kref *kref)
 {
        struct se_node_acl *nacl = container_of(kref,
                                struct se_node_acl, acl_kref);
+       struct se_portal_group *se_tpg = nacl->se_tpg;
 
-       complete(&nacl->acl_free_comp);
+       if (!nacl->dynamic_stop) {
+               complete(&nacl->acl_free_comp);
+               return;
+       }
+
+       mutex_lock(&se_tpg->acl_node_mutex);
+       list_del(&nacl->acl_list);
+       mutex_unlock(&se_tpg->acl_node_mutex);
+
+       core_tpg_wait_for_nacl_pr_ref(nacl);
+       core_free_device_list_for_node(nacl, se_tpg);
+       kfree(nacl);
 }
 
 void target_put_nacl(struct se_node_acl *nacl)
@@ -499,12 +511,39 @@ EXPORT_SYMBOL(transport_deregister_session_configfs);
 void transport_free_session(struct se_session *se_sess)
 {
        struct se_node_acl *se_nacl = se_sess->se_node_acl;
+
        /*
         * Drop the se_node_acl->nacl_kref obtained from within
         * core_tpg_get_initiator_node_acl().
         */
        if (se_nacl) {
+               struct se_portal_group *se_tpg = se_nacl->se_tpg;
+               const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
+               unsigned long flags;
+
                se_sess->se_node_acl = NULL;
+
+               /*
+                * Also determine if we need to drop the extra ->cmd_kref if
+                * it had been previously dynamically generated, and
+                * the endpoint is not caching dynamic ACLs.
+                */
+               mutex_lock(&se_tpg->acl_node_mutex);
+               if (se_nacl->dynamic_node_acl &&
+                   !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
+                       spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
+                       if (list_empty(&se_nacl->acl_sess_list))
+                               se_nacl->dynamic_stop = true;
+                       spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
+
+                       if (se_nacl->dynamic_stop)
+                               list_del(&se_nacl->acl_list);
+               }
+               mutex_unlock(&se_tpg->acl_node_mutex);
+
+               if (se_nacl->dynamic_stop)
+                       target_put_nacl(se_nacl);
+
                target_put_nacl(se_nacl);
        }
        if (se_sess->sess_cmd_map) {
@@ -518,16 +557,12 @@ EXPORT_SYMBOL(transport_free_session);
 void transport_deregister_session(struct se_session *se_sess)
 {
        struct se_portal_group *se_tpg = se_sess->se_tpg;
-       const struct target_core_fabric_ops *se_tfo;
-       struct se_node_acl *se_nacl;
        unsigned long flags;
-       bool drop_nacl = false;
 
        if (!se_tpg) {
                transport_free_session(se_sess);
                return;
        }
-       se_tfo = se_tpg->se_tpg_tfo;
 
        spin_lock_irqsave(&se_tpg->session_lock, flags);
        list_del(&se_sess->sess_list);
@@ -535,33 +570,15 @@ void transport_deregister_session(struct se_session *se_sess)
        se_sess->fabric_sess_ptr = NULL;
        spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 
-       /*
-        * Determine if we need to do extra work for this initiator node's
-        * struct se_node_acl if it had been previously dynamically generated.
-        */
-       se_nacl = se_sess->se_node_acl;
-
-       mutex_lock(&se_tpg->acl_node_mutex);
-       if (se_nacl && se_nacl->dynamic_node_acl) {
-               if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
-                       list_del(&se_nacl->acl_list);
-                       drop_nacl = true;
-               }
-       }
-       mutex_unlock(&se_tpg->acl_node_mutex);
-
-       if (drop_nacl) {
-               core_tpg_wait_for_nacl_pr_ref(se_nacl);
-               core_free_device_list_for_node(se_nacl, se_tpg);
-               se_sess->se_node_acl = NULL;
-               kfree(se_nacl);
-       }
        pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
                se_tpg->se_tpg_tfo->get_fabric_name());
        /*
         * If last kref is dropping now for an explicit NodeACL, awake sleeping
         * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
         * removal context from within transport_free_session() code.
+        *
+        * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
+        * to release all remaining generate_node_acl=1 created ACL resources.
         */
 
        transport_free_session(se_sess);
@@ -2748,11 +2765,8 @@ __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
 }
 
 /**
- * transport_wait_for_tasks - wait for completion to occur
- * @cmd:       command to wait
- *
- * Called from frontend fabric context to wait for storage engine
- * to pause and/or release frontend generated struct se_cmd.
+ * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
+ * @cmd: command to wait on
  */
 bool transport_wait_for_tasks(struct se_cmd *cmd)
 {
@@ -3110,7 +3124,6 @@ static void target_tmr_work(struct work_struct *work)
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
                goto check_stop;
        }
-       cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
        cmd->se_tfo->queue_tm_rsp(cmd);
@@ -3123,11 +3136,25 @@ int transport_generic_handle_tmr(
        struct se_cmd *cmd)
 {
        unsigned long flags;
+       bool aborted = false;
 
        spin_lock_irqsave(&cmd->t_state_lock, flags);
-       cmd->transport_state |= CMD_T_ACTIVE;
+       if (cmd->transport_state & CMD_T_ABORTED) {
+               aborted = true;
+       } else {
+               cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
+               cmd->transport_state |= CMD_T_ACTIVE;
+       }
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
+       if (aborted) {
+               pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d"
+                       "ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function,
+                       cmd->se_tmr_req->ref_task_tag, cmd->tag);
+               transport_cmd_check_stop_to_fabric(cmd);
+               return 0;
+       }
+
        INIT_WORK(&cmd->work, target_tmr_work);
        queue_work(cmd->se_dev->tmr_wq, &cmd->work);
        return 0;