+/**
+ * iscsi_create_session - create iscsi class session
+ * @shost: scsi host
+ * @transport: iscsi transport
+ *
+ * This can be called from a LLD or iscsi_transport
+ **/
+struct iscsi_cls_session *
+iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport)
+{
+ struct iscsi_cls_session *session;
+ int err;
+
+ if (!try_module_get(transport->owner))
+ return NULL;
+
+ session = kzalloc(sizeof(*session), GFP_KERNEL);
+ if (!session)
+ goto module_put;
+ session->transport = transport;
+
+ /* this is released in the dev's release function */
+ scsi_host_get(shost);
+ snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u", shost->host_no);
+ session->dev.parent = &shost->shost_gendev;
+ session->dev.release = iscsi_session_release;
+ err = device_register(&session->dev);
+ if (err) {
+ dev_printk(KERN_ERR, &session->dev, "iscsi: could not "
+ "register session's dev\n");
+ goto free_session;
+ }
+ transport_register_device(&session->dev);
+
+ return session;
+
+free_session:
+ kfree(session);
+module_put:
+ module_put(transport->owner);
+ return NULL;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_create_session);
+
+/**
+ * iscsi_destroy_session - destroy iscsi session
+ * @session: iscsi_session
+ *
+ * Can be called by a LLD or iscsi_transport. There must not be
+ * any running connections.
+ **/
+int iscsi_destroy_session(struct iscsi_cls_session *session)
+{
+ transport_unregister_device(&session->dev);
+ device_unregister(&session->dev);
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_destroy_session);
+
+static void iscsi_conn_release(struct device *dev)
+{
+ struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
+ struct device *parent = conn->dev.parent;
+
+ kfree(conn);
+ put_device(parent);
+}
+
+static int iscsi_is_conn_dev(const struct device *dev)
+{
+ return dev->release == iscsi_conn_release;
+}
+
+/**
+ * iscsi_create_conn - create iscsi class connection
+ * @session: iscsi cls session
+ * @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.
+ **/
+struct iscsi_cls_conn *
+iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
+{
+ struct iscsi_transport *transport = session->transport;
+ struct Scsi_Host *shost = iscsi_session_to_shost(session);
+ struct iscsi_cls_conn *conn;
+ int err;
+
+ conn = kzalloc(sizeof(*conn) + transport->conndata_size, GFP_KERNEL);
+ if (!conn)
+ return NULL;
+
+ if (transport->conndata_size)
+ conn->dd_data = &conn[1];
+
+ INIT_LIST_HEAD(&conn->conn_list);
+ conn->transport = transport;
+
+ /* this is released in the dev's release function */
+ if (!get_device(&session->dev))
+ goto free_conn;
+ snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
+ shost->host_no, cid);
+ conn->dev.parent = &session->dev;
+ conn->dev.release = iscsi_conn_release;
+ err = device_register(&conn->dev);
+ if (err) {
+ dev_printk(KERN_ERR, &conn->dev, "iscsi: could not register "
+ "connection's dev\n");
+ goto release_parent_ref;
+ }
+ transport_register_device(&conn->dev);
+ return conn;
+
+release_parent_ref:
+ put_device(&session->dev);
+free_conn:
+ kfree(conn);
+ return NULL;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_create_conn);
+
+/**
+ * iscsi_destroy_conn - destroy iscsi class connection
+ * @session: iscsi cls session
+ *
+ * This can be called from a LLD or iscsi_transport.
+ **/
+int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
+{
+ transport_unregister_device(&conn->dev);
+ device_unregister(&conn->dev);
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
+
+/*
+ * These functions are used only by software iscsi_transports
+ * which do not allocate and more their scsi_hosts since this
+ * is initiated from userspace.
+ */
+
+/*
+ * iSCSI Session's hostdata organization:
+ *
+ * *------------------* <== hostdata_session(host->hostdata)
+ * | ptr to class sess|
+ * |------------------| <== iscsi_hostdata(host->hostdata)
+ * | transport's data |
+ * *------------------*
+ */
+
+#define hostdata_privsize(_t) (sizeof(unsigned long) + _t->hostdata_size + \
+ _t->hostdata_size % sizeof(unsigned long))
+
+#define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
+
+/**
+ * iscsi_transport_create_session - create iscsi cls session and host
+ * scsit: scsi transport template
+ * transport: iscsi transport template
+ *
+ * This can be used by software iscsi_transports that allocate
+ * a session per scsi host.
+ **/
+struct Scsi_Host *
+iscsi_transport_create_session(struct scsi_transport_template *scsit,
+ struct iscsi_transport *transport)
+{
+ struct iscsi_cls_session *session;
+ struct Scsi_Host *shost;
+
+ shost = scsi_host_alloc(transport->host_template,
+ hostdata_privsize(transport));
+ if (!shost) {
+ printk(KERN_ERR "iscsi: can not allocate SCSI host for "
+ "session\n");
+ return NULL;
+ }
+
+ shost->max_id = 1;
+ shost->max_channel = 0;
+ shost->max_lun = transport->max_lun;
+ shost->max_cmd_len = transport->max_cmd_len;
+ shost->transportt = scsit;
+ shost->transportt->create_work_queue = 1;
+
+ if (scsi_add_host(shost, NULL))
+ goto free_host;
+
+ session = iscsi_create_session(shost, transport);
+ if (!session)
+ goto remove_host;