Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 77 insertions, 0 deletions

diff --git a/kernel/net/netrom/nr_loopback.c b/kernel/net/netrom/nr_loopback.c
new file mode 100644
index 000000000..94d4e922a
--- /dev/null
+++ b/kernel/net/netrom/nr_loopback.c
@@ -0,0 +1,77 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
+ */
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/socket.h>
+#include <linux/timer.h>
+#include <net/ax25.h>
+#include <linux/skbuff.h>
+#include <net/netrom.h>
+#include <linux/init.h>
+
+static void nr_loopback_timer(unsigned long);
+
+static struct sk_buff_head loopback_queue;
+static DEFINE_TIMER(loopback_timer, nr_loopback_timer, 0, 0);
+
+void __init nr_loopback_init(void)
+{
+	skb_queue_head_init(&loopback_queue);
+}
+
+static inline int nr_loopback_running(void)
+{
+	return timer_pending(&loopback_timer);
+}
+
+int nr_loopback_queue(struct sk_buff *skb)
+{
+	struct sk_buff *skbn;
+
+	if ((skbn = alloc_skb(skb->len, GFP_ATOMIC)) != NULL) {
+		skb_copy_from_linear_data(skb, skb_put(skbn, skb->len), skb->len);
+		skb_reset_transport_header(skbn);
+
+		skb_queue_tail(&loopback_queue, skbn);
+
+		if (!nr_loopback_running())
+			mod_timer(&loopback_timer, jiffies + 10);
+	}
+
+	kfree_skb(skb);
+	return 1;
+}
+
+static void nr_loopback_timer(unsigned long param)
+{
+	struct sk_buff *skb;
+	ax25_address *nr_dest;
+	struct net_device *dev;
+
+	if ((skb = skb_dequeue(&loopback_queue)) != NULL) {
+		nr_dest = (ax25_address *)(skb->data + 7);
+
+		dev = nr_dev_get(nr_dest);
+
+		if (dev == NULL || nr_rx_frame(skb, dev) == 0)
+			kfree_skb(skb);
+
+		if (dev != NULL)
+			dev_put(dev);
+
+		if (!skb_queue_empty(&loopback_queue) && !nr_loopback_running())
+			mod_timer(&loopback_timer, jiffies + 10);
+	}
+}
+
+void __exit nr_loopback_clear(void)
+{
+	del_timer_sync(&loopback_timer);
+	skb_queue_purge(&loopback_queue);
+}