v4.19.13 snapshot.
diff --git a/include/net/9p/transport.h b/include/net/9p/transport.h
new file mode 100644
index 0000000..1625fb8
--- /dev/null
+++ b/include/net/9p/transport.h
@@ -0,0 +1,73 @@
+/*
+ * include/net/9p/transport.h
+ *
+ * Transport Definition
+ *
+ * Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net>
+ * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to:
+ * Free Software Foundation
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA 02111-1301 USA
+ *
+ */
+
+#ifndef NET_9P_TRANSPORT_H
+#define NET_9P_TRANSPORT_H
+
+#define P9_DEF_MIN_RESVPORT (665U)
+#define P9_DEF_MAX_RESVPORT (1023U)
+
+/**
+ * struct p9_trans_module - transport module interface
+ * @list: used to maintain a list of currently available transports
+ * @name: the human-readable name of the transport
+ * @maxsize: transport provided maximum packet size
+ * @def: set if this transport should be considered the default
+ * @create: member function to create a new connection on this transport
+ * @close: member function to discard a connection on this transport
+ * @request: member function to issue a request to the transport
+ * @cancel: member function to cancel a request (if it hasn't been sent)
+ * @cancelled: member function to notify that a cancelled request will not
+ * not receive a reply
+ *
+ * This is the basic API for a transport module which is registered by the
+ * transport module with the 9P core network module and used by the client
+ * to instantiate a new connection on a transport.
+ *
+ * The transport module list is protected by v9fs_trans_lock.
+ */
+
+struct p9_trans_module {
+ struct list_head list;
+ char *name; /* name of transport */
+ int maxsize; /* max message size of transport */
+ int def; /* this transport should be default */
+ struct module *owner;
+ int (*create)(struct p9_client *, const char *, char *);
+ void (*close) (struct p9_client *);
+ int (*request) (struct p9_client *, struct p9_req_t *req);
+ int (*cancel) (struct p9_client *, struct p9_req_t *req);
+ int (*cancelled)(struct p9_client *, struct p9_req_t *req);
+ int (*zc_request)(struct p9_client *, struct p9_req_t *,
+ struct iov_iter *, struct iov_iter *, int , int, int);
+ int (*show_options)(struct seq_file *, struct p9_client *);
+};
+
+void v9fs_register_trans(struct p9_trans_module *m);
+void v9fs_unregister_trans(struct p9_trans_module *m);
+struct p9_trans_module *v9fs_get_trans_by_name(char *s);
+struct p9_trans_module *v9fs_get_default_trans(void);
+void v9fs_put_trans(struct p9_trans_module *m);
+#endif /* NET_9P_TRANSPORT_H */