1 files changed, 76 insertions, 108 deletions

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 554b6f784223..27951ea05dd4 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -87,7 +87,6 @@ struct iscsi_internal {
 };
 
 static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
-static struct workqueue_struct *iscsi_eh_timer_workq;
 
 static struct workqueue_struct *iscsi_conn_cleanup_workq;
 
@@ -1557,7 +1556,6 @@ static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 	struct iscsi_cls_host *ihost = shost->shost_data;
 
 	memset(ihost, 0, sizeof(*ihost));
-	atomic_set(&ihost->nr_scans, 0);
 	mutex_init(&ihost->mutex);
 
 	iscsi_bsg_host_add(shost, ihost);
@@ -1744,25 +1742,6 @@ void iscsi_host_for_each_session(struct Scsi_Host *shost,
 }
 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 
-/**
- * iscsi_scan_finished - helper to report when running scans are done
- * @shost: scsi host
- * @time: scan run time
- *
- * This function can be used by drives like qla4xxx to report to the scsi
- * layer when the scans it kicked off at module load time are done.
- */
-int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
-{
-	struct iscsi_cls_host *ihost = shost->shost_data;
-	/*
-	 * qla4xxx will have kicked off some session unblocks before calling
-	 * scsi_scan_host, so just wait for them to complete.
-	 */
-	return !atomic_read(&ihost->nr_scans);
-}
-EXPORT_SYMBOL_GPL(iscsi_scan_finished);
-
 struct iscsi_scan_data {
 	unsigned int channel;
 	unsigned int id;
@@ -1831,8 +1810,6 @@ static void iscsi_scan_session(struct work_struct *work)
 {
 	struct iscsi_cls_session *session =
 			container_of(work, struct iscsi_cls_session, scan_work);
-	struct Scsi_Host *shost = iscsi_session_to_shost(session);
-	struct iscsi_cls_host *ihost = shost->shost_data;
 	struct iscsi_scan_data scan_data;
 
 	scan_data.channel = 0;
@@ -1841,7 +1818,6 @@ static void iscsi_scan_session(struct work_struct *work)
 	scan_data.rescan = SCSI_SCAN_RESCAN;
 
 	iscsi_user_scan_session(&session->dev, &scan_data);
-	atomic_dec(&ihost->nr_scans);
 }
 
 /**
@@ -1912,30 +1888,16 @@ static void __iscsi_unblock_session(struct work_struct *work)
 	struct iscsi_cls_session *session =
 			container_of(work, struct iscsi_cls_session,
 				     unblock_work);
-	struct Scsi_Host *shost = iscsi_session_to_shost(session);
-	struct iscsi_cls_host *ihost = shost->shost_data;
 	unsigned long flags;
 
 	ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
-	/*
-	 * The recovery and unblock work get run from the same workqueue,
-	 * so try to cancel it if it was going to run after this unblock.
-	 */
-	cancel_delayed_work(&session->recovery_work);
+
+	cancel_delayed_work_sync(&session->recovery_work);
 	spin_lock_irqsave(&session->lock, flags);
 	session->state = ISCSI_SESSION_LOGGED_IN;
 	spin_unlock_irqrestore(&session->lock, flags);
 	/* start IO */
 	scsi_target_unblock(&session->dev, SDEV_RUNNING);
-	/*
-	 * Only do kernel scanning if the driver is properly hooked into
-	 * the async scanning code (drivers like iscsi_tcp do login and
-	 * scanning from userspace).
-	 */
-	if (shost->hostt->scan_finished) {
-		if (scsi_queue_work(shost, &session->scan_work))
-			atomic_inc(&ihost->nr_scans);
-	}
 	ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
 }
 
@@ -1947,9 +1909,10 @@ static void __iscsi_unblock_session(struct work_struct *work)
  */
 void iscsi_unblock_session(struct iscsi_cls_session *session)
 {
-	flush_work(&session->block_work);
+	if (!cancel_work_sync(&session->block_work))
+		cancel_delayed_work_sync(&session->recovery_work);
 
-	queue_work(iscsi_eh_timer_workq, &session->unblock_work);
+	queue_work(session->workq, &session->unblock_work);
 	/*
 	 * Blocking the session can be done from any context so we only
 	 * queue the block work. Make sure the unblock work has completed
@@ -1973,14 +1936,14 @@ static void __iscsi_block_session(struct work_struct *work)
 	scsi_target_block(&session->dev);
 	ISCSI_DBG_TRANS_SESSION(session, "Completed SCSI target blocking\n");
 	if (session->recovery_tmo >= 0)
-		queue_delayed_work(iscsi_eh_timer_workq,
+		queue_delayed_work(session->workq,
 				   &session->recovery_work,
 				   session->recovery_tmo * HZ);
 }
 
 void iscsi_block_session(struct iscsi_cls_session *session)
 {
-	queue_work(iscsi_eh_timer_workq, &session->block_work);
+	queue_work(session->workq, &session->block_work);
 }
 EXPORT_SYMBOL_GPL(iscsi_block_session);
 
@@ -2068,19 +2031,27 @@ EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 
 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 {
+	struct Scsi_Host *shost = iscsi_session_to_shost(session);
 	unsigned long flags;
 	int id = 0;
 	int err;
 
 	session->sid = atomic_add_return(1, &iscsi_session_nr);
 
+	session->workq = alloc_workqueue("iscsi_ctrl_%d:%d",
+			WQ_SYSFS | WQ_MEM_RECLAIM | WQ_UNBOUND, 0,
+			shost->host_no, session->sid);
+	if (!session->workq)
+		return -ENOMEM;
+
 	if (target_id == ISCSI_MAX_TARGET) {
 		id = ida_simple_get(&iscsi_sess_ida, 0, 0, GFP_KERNEL);
 
 		if (id < 0) {
 			iscsi_cls_session_printk(KERN_ERR, session,
 					"Failure in Target ID Allocation\n");
-			return id;
+			err = id;
+			goto destroy_wq;
 		}
 		session->target_id = (unsigned int)id;
 		session->ida_used = true;
@@ -2114,7 +2085,8 @@ release_dev:
 release_ida:
 	if (session->ida_used)
 		ida_simple_remove(&iscsi_sess_ida, session->target_id);
-
+destroy_wq:
+	destroy_workqueue(session->workq);
 	return err;
 }
 EXPORT_SYMBOL_GPL(iscsi_add_session);
@@ -2165,7 +2137,11 @@ static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 {
 	if (!iscsi_is_conn_dev(dev))
 		return 0;
-	return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
+
+	iscsi_remove_conn(iscsi_dev_to_conn(dev));
+	iscsi_put_conn(iscsi_dev_to_conn(dev));
+
+	return 0;
 }
 
 void iscsi_remove_session(struct iscsi_cls_session *session)
@@ -2180,9 +2156,9 @@ void iscsi_remove_session(struct iscsi_cls_session *session)
 		list_del(&session->sess_list);
 	spin_unlock_irqrestore(&sesslock, flags);
 
-	flush_work(&session->block_work);
-	flush_work(&session->unblock_work);
-	cancel_delayed_work_sync(&session->recovery_work);
+	if (!cancel_work_sync(&session->block_work))
+		cancel_delayed_work_sync(&session->recovery_work);
+	cancel_work_sync(&session->unblock_work);
 	/*
 	 * If we are blocked let commands flow again. The lld or iscsi
 	 * layer should set up the queuecommand to fail commands.
@@ -2194,7 +2170,10 @@ void iscsi_remove_session(struct iscsi_cls_session *session)
 	spin_unlock_irqrestore(&session->lock, flags);
 
 	scsi_target_unblock(&session->dev, SDEV_TRANSPORT_OFFLINE);
-	/* flush running scans then delete devices */
+	/*
+	 * qla4xxx can perform it's own scans when it runs in kernel only
+	 * mode. Make sure to flush those scans.
+	 */
 	flush_work(&session->scan_work);
 	/* flush running unbind operations */
 	flush_work(&session->unbind_work);
@@ -2210,6 +2189,8 @@ void iscsi_remove_session(struct iscsi_cls_session *session)
 
 	transport_unregister_device(&session->dev);
 
+	destroy_workqueue(session->workq);
+
 	ISCSI_DBG_TRANS_SESSION(session, "Completing session removal\n");
 	device_del(&session->dev);
 }
@@ -2341,27 +2322,16 @@ void iscsi_free_session(struct iscsi_cls_session *session)
 EXPORT_SYMBOL_GPL(iscsi_free_session);
 
 /**
- * iscsi_create_conn - create iscsi class connection
+ * iscsi_alloc_conn - alloc iscsi class connection
  * @session: iscsi cls session
  * @dd_size: private driver data size
  * @cid: connection id
- *
- * This can be called from a LLD or iscsi_transport. The connection
- * is child of the session so cid must be unique for all connections
- * on the session.
- *
- * Since we do not support MCS, cid will normally be zero. In some cases
- * for software iscsi we could be trying to preallocate a connection struct
- * in which case there could be two connection structs and cid would be
- * non-zero.
  */
 struct iscsi_cls_conn *
-iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
+iscsi_alloc_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 {
 	struct iscsi_transport *transport = session->transport;
 	struct iscsi_cls_conn *conn;
-	unsigned long flags;
-	int err;
 
 	conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 	if (!conn)
@@ -2381,48 +2351,61 @@ iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 		goto free_conn;
 
 	dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
+	device_initialize(&conn->dev);
 	conn->dev.parent = &session->dev;
 	conn->dev.release = iscsi_conn_release;
-	err = device_register(&conn->dev);
+
+	return conn;
+
+free_conn:
+	kfree(conn);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(iscsi_alloc_conn);
+
+/**
+ * iscsi_add_conn - add iscsi class connection
+ * @conn: iscsi cls connection
+ *
+ * This will expose iscsi_cls_conn to sysfs so make sure the related
+ * resources for sysfs attributes are initialized before calling this.
+ */
+int iscsi_add_conn(struct iscsi_cls_conn *conn)
+{
+	int err;
+	unsigned long flags;
+	struct iscsi_cls_session *session = iscsi_dev_to_session(conn->dev.parent);
+
+	err = device_add(&conn->dev);
 	if (err) {
-		iscsi_cls_session_printk(KERN_ERR, session, "could not "
-					 "register connection's dev\n");
-		goto release_parent_ref;
+		iscsi_cls_session_printk(KERN_ERR, session,
+					 "could not register connection's dev\n");
+		return err;
 	}
 	err = transport_register_device(&conn->dev);
 	if (err) {
-		iscsi_cls_session_printk(KERN_ERR, session, "could not "
-					 "register transport's dev\n");
-		goto release_conn_ref;
+		iscsi_cls_session_printk(KERN_ERR, session,
+					 "could not register transport's dev\n");
+		device_del(&conn->dev);
+		return err;
 	}
 
 	spin_lock_irqsave(&connlock, flags);
 	list_add(&conn->conn_list, &connlist);
 	spin_unlock_irqrestore(&connlock, flags);
 
-	ISCSI_DBG_TRANS_CONN(conn, "Completed conn creation\n");
-	return conn;
-
-release_conn_ref:
-	device_unregister(&conn->dev);
-	put_device(&session->dev);
-	return NULL;
-release_parent_ref:
-	put_device(&session->dev);
-free_conn:
-	kfree(conn);
-	return NULL;
+	return 0;
 }
-
-EXPORT_SYMBOL_GPL(iscsi_create_conn);
+EXPORT_SYMBOL_GPL(iscsi_add_conn);
 
 /**
- * iscsi_destroy_conn - destroy iscsi class connection
- * @conn: iscsi cls session
+ * iscsi_remove_conn - remove iscsi class connection from sysfs
+ * @conn: iscsi cls connection
  *
- * This can be called from a LLD or iscsi_transport.
+ * Remove iscsi_cls_conn from sysfs, and wait for previous
+ * read/write of iscsi_cls_conn's attributes in sysfs to finish.
  */
-int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
+void iscsi_remove_conn(struct iscsi_cls_conn *conn)
 {
 	unsigned long flags;
 
@@ -2431,11 +2414,9 @@ int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 	spin_unlock_irqrestore(&connlock, flags);
 
 	transport_unregister_device(&conn->dev);
-	ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n");
-	device_unregister(&conn->dev);
-	return 0;
+	device_del(&conn->dev);
 }
-EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
+EXPORT_SYMBOL_GPL(iscsi_remove_conn);
 
 void iscsi_put_conn(struct iscsi_cls_conn *conn)
 {
@@ -3866,8 +3847,7 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
 	case ISCSI_UEVENT_UNBIND_SESSION:
 		session = iscsi_session_lookup(ev->u.d_session.sid);
 		if (session)
-			scsi_queue_work(iscsi_session_to_shost(session),
-					&session->unbind_work);
+			queue_work(session->workq, &session->unbind_work);
 		else
 			err = -EINVAL;
 		break;
@@ -4740,7 +4720,6 @@ iscsi_register_transport(struct iscsi_transport *tt)
 	INIT_LIST_HEAD(&priv->list);
 	priv->iscsi_transport = tt;
 	priv->t.user_scan = iscsi_user_scan;
-	priv->t.create_work_queue = 1;
 
 	priv->dev.class = &iscsi_transport_class;
 	dev_set_name(&priv->dev, "%s", tt->name);
@@ -4875,26 +4854,16 @@ static __init int iscsi_transport_init(void)
 		goto unregister_flashnode_bus;
 	}
 
-	iscsi_eh_timer_workq = alloc_workqueue("%s",
-			WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND,
-			1, "iscsi_eh");
-	if (!iscsi_eh_timer_workq) {
-		err = -ENOMEM;
-		goto release_nls;
-	}
-
 	iscsi_conn_cleanup_workq = alloc_workqueue("%s",
 			WQ_SYSFS | WQ_MEM_RECLAIM | WQ_UNBOUND, 0,
 			"iscsi_conn_cleanup");
 	if (!iscsi_conn_cleanup_workq) {
 		err = -ENOMEM;
-		goto destroy_wq;
+		goto release_nls;
 	}
 
 	return 0;
 
-destroy_wq:
-	destroy_workqueue(iscsi_eh_timer_workq);
 release_nls:
 	netlink_kernel_release(nls);
 unregister_flashnode_bus:
@@ -4917,7 +4886,6 @@ unregister_transport_class:
 static void __exit iscsi_transport_exit(void)
 {
 	destroy_workqueue(iscsi_conn_cleanup_workq);
-	destroy_workqueue(iscsi_eh_timer_workq);
 	netlink_kernel_release(nls);
 	bus_unregister(&iscsi_flashnode_bus);
 	transport_class_unregister(&iscsi_connection_class);