v4.19.13 snapshot.
diff --git a/net/9p/mod.c b/net/9p/mod.c
new file mode 100644
index 0000000..253ba82
--- /dev/null
+++ b/net/9p/mod.c
@@ -0,0 +1,199 @@
+/*
+ * net/9p/9p.c
+ *
+ * 9P entry point
+ *
+ * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ * 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
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/moduleparam.h>
+#include <net/9p/9p.h>
+#include <linux/fs.h>
+#include <linux/parser.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+
+#ifdef CONFIG_NET_9P_DEBUG
+unsigned int p9_debug_level = 0; /* feature-rific global debug level */
+EXPORT_SYMBOL(p9_debug_level);
+module_param_named(debug, p9_debug_level, uint, 0);
+MODULE_PARM_DESC(debug, "9P debugging level");
+
+void _p9_debug(enum p9_debug_flags level, const char *func,
+ const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+
+ if ((p9_debug_level & level) != level)
+ return;
+
+ va_start(args, fmt);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ if (level == P9_DEBUG_9P)
+ pr_notice("(%8.8d) %pV", task_pid_nr(current), &vaf);
+ else
+ pr_notice("-- %s (%d): %pV", func, task_pid_nr(current), &vaf);
+
+ va_end(args);
+}
+EXPORT_SYMBOL(_p9_debug);
+#endif
+
+/*
+ * Dynamic Transport Registration Routines
+ *
+ */
+
+static DEFINE_SPINLOCK(v9fs_trans_lock);
+static LIST_HEAD(v9fs_trans_list);
+
+/**
+ * v9fs_register_trans - register a new transport with 9p
+ * @m: structure describing the transport module and entry points
+ *
+ */
+void v9fs_register_trans(struct p9_trans_module *m)
+{
+ spin_lock(&v9fs_trans_lock);
+ list_add_tail(&m->list, &v9fs_trans_list);
+ spin_unlock(&v9fs_trans_lock);
+}
+EXPORT_SYMBOL(v9fs_register_trans);
+
+/**
+ * v9fs_unregister_trans - unregister a 9p transport
+ * @m: the transport to remove
+ *
+ */
+void v9fs_unregister_trans(struct p9_trans_module *m)
+{
+ spin_lock(&v9fs_trans_lock);
+ list_del_init(&m->list);
+ spin_unlock(&v9fs_trans_lock);
+}
+EXPORT_SYMBOL(v9fs_unregister_trans);
+
+/**
+ * v9fs_get_trans_by_name - get transport with the matching name
+ * @s: string identifying transport
+ *
+ */
+struct p9_trans_module *v9fs_get_trans_by_name(char *s)
+{
+ struct p9_trans_module *t, *found = NULL;
+
+ spin_lock(&v9fs_trans_lock);
+
+ list_for_each_entry(t, &v9fs_trans_list, list)
+ if (strcmp(t->name, s) == 0 &&
+ try_module_get(t->owner)) {
+ found = t;
+ break;
+ }
+
+ spin_unlock(&v9fs_trans_lock);
+ return found;
+}
+EXPORT_SYMBOL(v9fs_get_trans_by_name);
+
+/**
+ * v9fs_get_default_trans - get the default transport
+ *
+ */
+
+struct p9_trans_module *v9fs_get_default_trans(void)
+{
+ struct p9_trans_module *t, *found = NULL;
+
+ spin_lock(&v9fs_trans_lock);
+
+ list_for_each_entry(t, &v9fs_trans_list, list)
+ if (t->def && try_module_get(t->owner)) {
+ found = t;
+ break;
+ }
+
+ if (!found)
+ list_for_each_entry(t, &v9fs_trans_list, list)
+ if (try_module_get(t->owner)) {
+ found = t;
+ break;
+ }
+
+ spin_unlock(&v9fs_trans_lock);
+ return found;
+}
+EXPORT_SYMBOL(v9fs_get_default_trans);
+
+/**
+ * v9fs_put_trans - put trans
+ * @m: transport to put
+ *
+ */
+void v9fs_put_trans(struct p9_trans_module *m)
+{
+ if (m)
+ module_put(m->owner);
+}
+
+/**
+ * init_p9 - Initialize module
+ *
+ */
+static int __init init_p9(void)
+{
+ p9_error_init();
+ pr_info("Installing 9P2000 support\n");
+ p9_trans_fd_init();
+
+ return 0;
+}
+
+/**
+ * exit_p9 - shutdown module
+ *
+ */
+
+static void __exit exit_p9(void)
+{
+ pr_info("Unloading 9P2000 support\n");
+
+ p9_trans_fd_exit();
+}
+
+module_init(init_p9)
+module_exit(exit_p9)
+
+MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
+MODULE_LICENSE("GPL");