target: consolidate and fix session shutdown
authorChristoph Hellwig <hch@lst.de>
Mon, 2 May 2016 13:45:19 +0000 (15:45 +0200)
committerNicholas Bellinger <nab@linux-iscsi.org>
Tue, 10 May 2016 08:19:03 +0000 (01:19 -0700)
Factor out a helper to shutdown sessions for a Node ACL, and make it
properly restart the list walk after dropping the lock.

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

index ddf046080dc3ae166646757eadaf9ce05f17c2eb..88db4938600b869e2c733061d1b00984614a7e7d 100644 (file)
@@ -336,44 +336,47 @@ struct se_node_acl *core_tpg_add_initiator_node_acl(
        return acl;
 }
 
-void core_tpg_del_initiator_node_acl(struct se_node_acl *acl)
+static void target_shutdown_sessions(struct se_node_acl *acl, bool acl_stop)
 {
-       struct se_portal_group *tpg = acl->se_tpg;
-       LIST_HEAD(sess_list);
-       struct se_session *sess, *sess_tmp;
+       struct se_session *sess;
        unsigned long flags;
-       int rc;
-
-       mutex_lock(&tpg->acl_node_mutex);
-       if (acl->dynamic_node_acl) {
-               acl->dynamic_node_acl = 0;
-       }
-       list_del(&acl->acl_list);
-       mutex_unlock(&tpg->acl_node_mutex);
+       int ret;
 
        spin_lock_irqsave(&acl->nacl_sess_lock, flags);
-       acl->acl_stop = 1;
-
-       list_for_each_entry_safe(sess, sess_tmp, &acl->acl_sess_list,
-                               sess_acl_list) {
-               if (sess->sess_tearing_down != 0)
+       if (acl_stop)
+               acl->acl_stop = 1;
+restart:
+       list_for_each_entry(sess, &acl->acl_sess_list, sess_acl_list) {
+               if (sess->sess_tearing_down)
                        continue;
-
                if (!target_get_session(sess))
                        continue;
-               list_move(&sess->sess_acl_list, &sess_list);
-       }
-       spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
 
-       list_for_each_entry_safe(sess, sess_tmp, &sess_list, sess_acl_list) {
                list_del(&sess->sess_acl_list);
 
-               rc = tpg->se_tpg_tfo->shutdown_session(sess);
-               target_put_session(sess);
-               if (!rc)
-                       continue;
+               spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
+               ret = acl->se_tpg->se_tpg_tfo->shutdown_session(sess);
                target_put_session(sess);
+               if (ret)
+                       target_put_session(sess);
+               spin_lock_irqsave(&acl->nacl_sess_lock, flags);
+               goto restart;
        }
+       spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
+}
+
+void core_tpg_del_initiator_node_acl(struct se_node_acl *acl)
+{
+       struct se_portal_group *tpg = acl->se_tpg;
+
+       mutex_lock(&tpg->acl_node_mutex);
+       if (acl->dynamic_node_acl)
+               acl->dynamic_node_acl = 0;
+       list_del(&acl->acl_list);
+       mutex_unlock(&tpg->acl_node_mutex);
+
+       target_shutdown_sessions(acl, true);
+
        target_put_nacl(acl);
        /*
         * Wait for last target_put_nacl() to complete in target_complete_nacl()
@@ -400,11 +403,7 @@ int core_tpg_set_initiator_node_queue_depth(
        struct se_node_acl *acl,
        u32 queue_depth)
 {
-       LIST_HEAD(sess_list);
        struct se_portal_group *tpg = acl->se_tpg;
-       struct se_session *sess, *sess_tmp;
-       unsigned long flags;
-       int rc;
 
        /*
         * User has requested to change the queue depth for a Initiator Node.
@@ -413,30 +412,10 @@ int core_tpg_set_initiator_node_queue_depth(
         */
        target_set_nacl_queue_depth(tpg, acl, queue_depth);
 
-       spin_lock_irqsave(&acl->nacl_sess_lock, flags);
-       list_for_each_entry_safe(sess, sess_tmp, &acl->acl_sess_list,
-                                sess_acl_list) {
-               if (sess->sess_tearing_down != 0)
-                       continue;
-               if (!target_get_session(sess))
-                       continue;
-               spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
-
-               /*
-                * Finally call tpg->se_tpg_tfo->close_session() to force session
-                * reinstatement to occur if there is an active session for the
-                * $FABRIC_MOD Initiator Node in question.
-                */
-               rc = tpg->se_tpg_tfo->shutdown_session(sess);
-               target_put_session(sess);
-               if (!rc) {
-                       spin_lock_irqsave(&acl->nacl_sess_lock, flags);
-                       continue;
-               }
-               target_put_session(sess);
-               spin_lock_irqsave(&acl->nacl_sess_lock, flags);
-       }
-       spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
+       /*
+        * Shutdown all pending sessions to force session reinstatement.
+        */
+       target_shutdown_sessions(acl, false);
 
        pr_debug("Successfully changed queue depth to: %d for Initiator"
                " Node: %s on %s Target Portal Group: %u\n", acl->queue_depth,