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, 51 insertions, 0 deletions

diff --git a/kernel/arch/um/drivers/null.c b/kernel/arch/um/drivers/null.c
new file mode 100644
index 000000000..10495747c
--- /dev/null
+++ b/kernel/arch/um/drivers/null.c
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
+ * Licensed under the GPL
+ */
+
+#include <stddef.h>
+#include <errno.h>
+#include <fcntl.h>
+#include "chan_user.h"
+#include <os.h>
+
+/* This address is used only as a unique identifier */
+static int null_chan;
+
+static void *null_init(char *str, int device, const struct chan_opts *opts)
+{
+	return &null_chan;
+}
+
+static int null_open(int input, int output, int primary, void *d,
+		     char **dev_out)
+{
+	int fd;
+
+	*dev_out = NULL;
+
+	fd = open(DEV_NULL, O_RDWR);
+	return (fd < 0) ? -errno : fd;
+}
+
+static int null_read(int fd, char *c_out, void *unused)
+{
+	return -ENODEV;
+}
+
+static void null_free(void *data)
+{
+}
+
+const struct chan_ops null_ops = {
+	.type		= "null",
+	.init		= null_init,
+	.open		= null_open,
+	.close		= generic_close,
+	.read		= null_read,
+	.write		= generic_write,
+	.console_write	= generic_console_write,
+	.window_size	= generic_window_size,
+	.free		= null_free,
+	.winch		= 0,
+};