[dpdk-dev] [PATCH v4 1/5] lib/librte_vhost: mv vhost example to vhost lib directory for further code re-factoring

Huawei Xie huawei.xie at intel.com
Fri Sep 12 12:55:00 CEST 2014


This commit creates vhost library directory, and copies vhost example into it.

Signed-off-by: Huawei Xie <huawei.xie at intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev at intel.com>
Acked-by: Tommy Long <thomas.long at intel.com>
---
 examples/vhost/Makefile                      |   60 -
 examples/vhost/eventfd_link/Makefile         |   39 -
 examples/vhost/eventfd_link/eventfd_link.c   |  205 --
 examples/vhost/eventfd_link/eventfd_link.h   |   79 -
 examples/vhost/libvirt/qemu-wrap.py          |  367 ---
 examples/vhost/main.c                        | 3722 --------------------------
 examples/vhost/main.h                        |   86 -
 examples/vhost/vhost-net-cdev.c              |  367 ---
 examples/vhost/vhost-net-cdev.h              |   83 -
 examples/vhost/virtio-net.c                  | 1165 --------
 examples/vhost/virtio-net.h                  |  161 --
 lib/librte_vhost/Makefile                    |   60 +
 lib/librte_vhost/eventfd_link/Makefile       |   39 +
 lib/librte_vhost/eventfd_link/eventfd_link.c |  205 ++
 lib/librte_vhost/eventfd_link/eventfd_link.h |   79 +
 lib/librte_vhost/libvirt/qemu-wrap.py        |  367 +++
 lib/librte_vhost/main.c                      | 3722 ++++++++++++++++++++++++++
 lib/librte_vhost/main.h                      |   86 +
 lib/librte_vhost/vhost-net-cdev.c            |  367 +++
 lib/librte_vhost/vhost-net-cdev.h            |   83 +
 lib/librte_vhost/virtio-net.c                | 1165 ++++++++
 lib/librte_vhost/virtio-net.h                |  161 ++
 22 files changed, 6334 insertions(+), 6334 deletions(-)
 delete mode 100644 examples/vhost/Makefile
 delete mode 100644 examples/vhost/eventfd_link/Makefile
 delete mode 100644 examples/vhost/eventfd_link/eventfd_link.c
 delete mode 100644 examples/vhost/eventfd_link/eventfd_link.h
 delete mode 100755 examples/vhost/libvirt/qemu-wrap.py
 delete mode 100644 examples/vhost/main.c
 delete mode 100644 examples/vhost/main.h
 delete mode 100644 examples/vhost/vhost-net-cdev.c
 delete mode 100644 examples/vhost/vhost-net-cdev.h
 delete mode 100644 examples/vhost/virtio-net.c
 delete mode 100644 examples/vhost/virtio-net.h
 create mode 100644 lib/librte_vhost/Makefile
 create mode 100644 lib/librte_vhost/eventfd_link/Makefile
 create mode 100644 lib/librte_vhost/eventfd_link/eventfd_link.c
 create mode 100644 lib/librte_vhost/eventfd_link/eventfd_link.h
 create mode 100755 lib/librte_vhost/libvirt/qemu-wrap.py
 create mode 100644 lib/librte_vhost/main.c
 create mode 100644 lib/librte_vhost/main.h
 create mode 100644 lib/librte_vhost/vhost-net-cdev.c
 create mode 100644 lib/librte_vhost/vhost-net-cdev.h
 create mode 100644 lib/librte_vhost/virtio-net.c
 create mode 100644 lib/librte_vhost/virtio-net.h

diff --git a/examples/vhost/Makefile b/examples/vhost/Makefile
deleted file mode 100644
index f45f83f..0000000
--- a/examples/vhost/Makefile
+++ /dev/null
@@ -1,60 +0,0 @@
-#   BSD LICENSE
-#
-#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
-#   All rights reserved.
-#
-#   Redistribution and use in source and binary forms, with or without
-#   modification, are permitted provided that the following conditions
-#   are met:
-#
-#     * Redistributions of source code must retain the above copyright
-#       notice, this list of conditions and the following disclaimer.
-#     * Redistributions in binary form must reproduce the above copyright
-#       notice, this list of conditions and the following disclaimer in
-#       the documentation and/or other materials provided with the
-#       distribution.
-#     * Neither the name of Intel Corporation nor the names of its
-#       contributors may be used to endorse or promote products derived
-#       from this software without specific prior written permission.
-#
-#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-ifeq ($(RTE_SDK),)
-$(error "Please define RTE_SDK environment variable")
-endif
-
-# Default target, can be overriden by command line or environment
-RTE_TARGET ?= x86_64-native-linuxapp-gcc
-
-include $(RTE_SDK)/mk/rte.vars.mk
-
-ifneq ($(CONFIG_RTE_EXEC_ENV),"linuxapp")
-$(info This application can only operate in a linuxapp environment, \
-please change the definition of the RTE_TARGET environment variable)
-all:
-else
-
-# binary name
-APP = vhost-switch
-
-# all source are stored in SRCS-y
-#SRCS-y := cusedrv.c loopback-userspace.c
-SRCS-y := main.c virtio-net.c vhost-net-cdev.c
-
-CFLAGS += -O2 -I/usr/local/include -D_FILE_OFFSET_BITS=64 -Wno-unused-parameter
-CFLAGS += $(WERROR_FLAGS)
-LDFLAGS += -lfuse
-
-include $(RTE_SDK)/mk/rte.extapp.mk
-
-endif
diff --git a/examples/vhost/eventfd_link/Makefile b/examples/vhost/eventfd_link/Makefile
deleted file mode 100644
index fc3927b..0000000
--- a/examples/vhost/eventfd_link/Makefile
+++ /dev/null
@@ -1,39 +0,0 @@
-#   BSD LICENSE
-#
-#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
-#   All rights reserved.
-#
-#   Redistribution and use in source and binary forms, with or without
-#   modification, are permitted provided that the following conditions
-#   are met:
-#
-#     * Redistributions of source code must retain the above copyright
-#       notice, this list of conditions and the following disclaimer.
-#     * Redistributions in binary form must reproduce the above copyright
-#       notice, this list of conditions and the following disclaimer in
-#       the documentation and/or other materials provided with the
-#       distribution.
-#     * Neither the name of Intel Corporation nor the names of its
-#       contributors may be used to endorse or promote products derived
-#       from this software without specific prior written permission.
-#
-#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-obj-m += eventfd_link.o
-
-
-all:
-	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
-
-clean:
-	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
diff --git a/examples/vhost/eventfd_link/eventfd_link.c b/examples/vhost/eventfd_link/eventfd_link.c
deleted file mode 100644
index fc0653a..0000000
--- a/examples/vhost/eventfd_link/eventfd_link.c
+++ /dev/null
@@ -1,205 +0,0 @@
-/*-
- *  * GPL LICENSE SUMMARY
- *  *
- *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *  *
- *  *   This program is free software; you can redistribute it and/or modify
- *  *   it under the terms of version 2 of the GNU General Public License 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 the Free Software
- *  *   Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- *  *   The full GNU General Public License is included in this distribution
- *  *   in the file called LICENSE.GPL.
- *  *
- *  *   Contact Information:
- *  *   Intel Corporation
- *   */
-
-#include <linux/eventfd.h>
-#include <linux/miscdevice.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/rcupdate.h>
-#include <linux/file.h>
-#include <linux/slab.h>
-#include <linux/fs.h>
-#include <linux/mmu_context.h>
-#include <linux/sched.h>
-#include <asm/mmu_context.h>
-#include <linux/fdtable.h>
-
-#include "eventfd_link.h"
-
-
-/*
- * get_files_struct is copied from fs/file.c
- */
-struct files_struct *
-get_files_struct (struct task_struct *task)
-{
-	struct files_struct *files;
-
-	task_lock (task);
-	files = task->files;
-	if (files)
-		atomic_inc (&files->count);
-	task_unlock (task);
-
-	return files;
-}
-
-/*
- * put_files_struct is extracted from fs/file.c
- */
-void
-put_files_struct (struct files_struct *files)
-{
-	if (atomic_dec_and_test (&files->count))
-	{
-		BUG ();
-	}
-}
-
-
-static long
-eventfd_link_ioctl (struct file *f, unsigned int ioctl, unsigned long arg)
-{
-	void __user *argp = (void __user *) arg;
-	struct task_struct *task_target = NULL;
-	struct file *file;
-	struct files_struct *files;
-	struct fdtable *fdt;
-	struct eventfd_copy eventfd_copy;
-
-	switch (ioctl)
-	{
-		case EVENTFD_COPY:
-			if (copy_from_user (&eventfd_copy, argp, sizeof (struct eventfd_copy)))
-				return -EFAULT;
-
-			/*
-			 * Find the task struct for the target pid
-			 */
-			task_target =
-				pid_task (find_vpid (eventfd_copy.target_pid), PIDTYPE_PID);
-			if (task_target == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get mem ctx for target pid\n");
-				return -EFAULT;
-			}
-
-			files = get_files_struct (current);
-			if (files == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get files struct\n");
-				return -EFAULT;
-			}
-
-			rcu_read_lock ();
-			file = fcheck_files (files, eventfd_copy.source_fd);
-			if (file)
-			{
-				if (file->f_mode & FMODE_PATH
-						|| !atomic_long_inc_not_zero (&file->f_count))
-					file = NULL;
-			}
-			rcu_read_unlock ();
-			put_files_struct (files);
-
-			if (file == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get file from source pid\n");
-				return 0;
-			}
-
-			/*
-			 * Release the existing eventfd in the source process
-			 */
-			spin_lock (&files->file_lock);
-			filp_close (file, files);
-			fdt = files_fdtable (files);
-			fdt->fd[eventfd_copy.source_fd] = NULL;
-			spin_unlock (&files->file_lock);
-
-			/*
-			 * Find the file struct associated with the target fd.
-			 */
-
-			files = get_files_struct (task_target);
-			if (files == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get files struct\n");
-				return -EFAULT;
-			}
-
-			rcu_read_lock ();
-			file = fcheck_files (files, eventfd_copy.target_fd);
-			if (file)
-			{
-				if (file->f_mode & FMODE_PATH
-						|| !atomic_long_inc_not_zero (&file->f_count))
-					file = NULL;
-			}
-			rcu_read_unlock ();
-			put_files_struct (files);
-
-			if (file == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get file from target pid\n");
-				return 0;
-			}
-
-
-			/*
-			 * Install the file struct from the target process into the
-			 * file desciptor of the source process,
-			 */
-
-			fd_install (eventfd_copy.source_fd, file);
-
-			return 0;
-
-		default:
-			return -ENOIOCTLCMD;
-	}
-}
-
-static const struct file_operations eventfd_link_fops = {
-	.owner = THIS_MODULE,
-	.unlocked_ioctl = eventfd_link_ioctl,
-};
-
-
-static struct miscdevice eventfd_link_misc = {
-	.name = "eventfd-link",
-	.fops = &eventfd_link_fops,
-};
-
-static int __init
-eventfd_link_init (void)
-{
-	return misc_register (&eventfd_link_misc);
-}
-
-module_init (eventfd_link_init);
-
-static void __exit
-eventfd_link_exit (void)
-{
-	misc_deregister (&eventfd_link_misc);
-}
-
-module_exit (eventfd_link_exit);
-
-MODULE_VERSION ("0.0.1");
-MODULE_LICENSE ("GPL v2");
-MODULE_AUTHOR ("Anthony Fee");
-MODULE_DESCRIPTION ("Link eventfd");
-MODULE_ALIAS ("devname:eventfd-link");
diff --git a/examples/vhost/eventfd_link/eventfd_link.h b/examples/vhost/eventfd_link/eventfd_link.h
deleted file mode 100644
index a32a8dd..0000000
--- a/examples/vhost/eventfd_link/eventfd_link.h
+++ /dev/null
@@ -1,79 +0,0 @@
-/*-
- *  * This file is provided under a dual BSD/GPLv2 license.  When using or
- *  *   redistributing this file, you may do so under either license.
- *  *
- *  *   GPL LICENSE SUMMARY
- *  *
- *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *  *
- *  *   This program is free software; you can redistribute it and/or modify
- *  *   it under the terms of version 2 of the GNU General Public License 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 the Free Software
- *  *   Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- *  *   The full GNU General Public License is included in this distribution
- *  *   in the file called LICENSE.GPL.
- *  *
- *  *   Contact Information:
- *  *   Intel Corporation
- *  *
- *  *   BSD LICENSE
- *  *
- *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *  *   All rights reserved.
- *  *
- *  *   Redistribution and use in source and binary forms, with or without
- *  *   modification, are permitted provided that the following conditions
- *  *   are met:
- *  *
- *  *     * Redistributions of source code must retain the above copyright
- *  *       notice, this list of conditions and the following disclaimer.
- *  *     * Redistributions in binary form must reproduce the above copyright
- *  *       notice, this list of conditions and the following disclaimer in
- *  *       the documentation and/or other materials provided with the
- *  *       distribution.
- *  *     * Neither the name of Intel Corporation nor the names of its
- *  *       contributors may be used to endorse or promote products derived
- *  *       from this software without specific prior written permission.
- *  *
- *  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *  *
- *   */
-
-#ifndef _EVENTFD_LINK_H_
-#define _EVENTFD_LINK_H_
-
-/*
- *	ioctl to copy an fd entry in calling process to an fd in a target process
- */
-#define EVENTFD_COPY 1
-
-/*
- *	arguements for the EVENTFD_COPY ioctl
- */
-struct eventfd_copy {
-	// fd in the target pid
-    unsigned target_fd;
-	// fd in the calling pid
-    unsigned source_fd;
-	// pid of the target pid
-    pid_t target_pid;
-};
-#endif /* _EVENTFD_LINK_H_ */
diff --git a/examples/vhost/libvirt/qemu-wrap.py b/examples/vhost/libvirt/qemu-wrap.py
deleted file mode 100755
index e2d68a0..0000000
--- a/examples/vhost/libvirt/qemu-wrap.py
+++ /dev/null
@@ -1,367 +0,0 @@
-#!/usr/bin/python
-#/*
-# *   BSD LICENSE
-# *
-# *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
-# *   All rights reserved.
-# *
-# *   Redistribution and use in source and binary forms, with or without
-# *   modification, are permitted provided that the following conditions
-# *   are met:
-# *
-# *     * Redistributions of source code must retain the above copyright
-# *       notice, this list of conditions and the following disclaimer.
-# *     * Redistributions in binary form must reproduce the above copyright
-# *       notice, this list of conditions and the following disclaimer in
-# *       the documentation and/or other materials provided with the
-# *       distribution.
-# *     * Neither the name of Intel Corporation nor the names of its
-# *       contributors may be used to endorse or promote products derived
-# *       from this software without specific prior written permission.
-# *
-# *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-# */
-
-#####################################################################
-# This script is designed to modify the call to the QEMU emulator
-# to support userspace vhost when starting a guest machine through
-# libvirt with vhost enabled. The steps to enable this are as follows
-# and should be run as root:
-#
-# 1. Place this script in a libvirtd's binary search PATH ($PATH)
-#    A good location would be in the same directory that the QEMU
-#    binary is located
-#
-# 2. Ensure that the script has the same owner/group and file
-#    permissions as the QEMU binary
-#
-# 3. Update the VM xml file using "virsh edit VM.xml"
-#
-#    3.a) Set the VM to use the launch script
-#
-#    	Set the emulator path contained in the
-#		<emulator><emulator/> tags
-#
-#    	e.g replace <emulator>/usr/bin/qemu-kvm<emulator/>
-#        with    <emulator>/usr/bin/qemu-wrap.py<emulator/>
-#
-#	 3.b) Set the VM's device's to use vhost-net offload
-#
-#		<interface type="network">
-#       	<model type="virtio"/>
-#       	<driver name="vhost"/>
-#		<interface/>
-#
-# 4. Enable libvirt to access our userpace device file by adding it to
-#    controllers cgroup for libvirtd using the following steps
-#
-#   4.a) In /etc/libvirt/qemu.conf add/edit the following lines:
-#         1) cgroup_controllers = [ ... "devices", ... ]
-#		  2) clear_emulator_capabilities = 0
-#         3) user = "root"
-#         4) group = "root"
-#         5) cgroup_device_acl = [
-#                "/dev/null", "/dev/full", "/dev/zero",
-#                "/dev/random", "/dev/urandom",
-#                "/dev/ptmx", "/dev/kvm", "/dev/kqemu",
-#                "/dev/rtc", "/dev/hpet", "/dev/net/tun",
-#                "/dev/<devbase-name>-<index>",
-#            ]
-#
-#   4.b) Disable SELinux or set to permissive mode
-#
-#   4.c) Mount cgroup device controller
-#        "mkdir /dev/cgroup"
-#        "mount -t cgroup none /dev/cgroup -o devices"
-#
-#   4.d) Set hugetlbfs_mount variable - ( Optional )
-#        VMs using userspace vhost must use hugepage backed
-#        memory. This can be enabled in the libvirt XML
-#        config by adding a memory backing section to the
-#        XML config e.g.
-#             <memoryBacking>
-#             <hugepages/>
-#             </memoryBacking>
-#        This memory backing section should be added after the
-#        <memory> and <currentMemory> sections. This will add
-#        flags "-mem-prealloc -mem-path <path>" to the QEMU
-#        command line. The hugetlbfs_mount variable can be used
-#        to override the default <path> passed through by libvirt.
-#
-#        if "-mem-prealloc" or "-mem-path <path>" are not passed
-#        through and a vhost device is detected then these options will
-#        be automatically added by this script. This script will detect
-#        the system hugetlbfs mount point to be used for <path>. The
-#        default <path> for this script can be overidden by the
-#        hugetlbfs_dir variable in the configuration section of this script.
-#
-#
-#   4.e) Restart the libvirtd system process
-#        e.g. on Fedora "systemctl restart libvirtd.service"
-#
-#
-#   4.f) Edit the Configuration Parameters section of this script
-#        to point to the correct emulator location and set any
-#        addition options
-#
-# The script modifies the libvirtd Qemu call by modifying/adding
-# options based on the configuration parameters below.
-# NOTE:
-#     emul_path and us_vhost_path must be set
-#     All other parameters are optional
-#####################################################################
-
-
-#############################################
-# Configuration Parameters
-#############################################
-#Path to QEMU binary
-emul_path = "/usr/local/bin/qemu-system-x86_64"
-
-#Path to userspace vhost device file
-# This filename should match the --dev-basename --dev-index parameters of
-# the command used to launch the userspace vhost sample application e.g.
-# if the sample app lauch command is:
-#    ./build/vhost-switch ..... --dev-basename usvhost --dev-index 1
-# then this variable should be set to:
-#   us_vhost_path = "/dev/usvhost-1"
-us_vhost_path = "/dev/usvhost-1"
-
-#List of additional user defined emulation options. These options will
-#be added to all Qemu calls
-emul_opts_user = []
-
-#List of additional user defined emulation options for vhost only.
-#These options will only be added to vhost enabled guests
-emul_opts_user_vhost = []
-
-#For all VHOST enabled VMs, the VM memory is preallocated from hugetlbfs
-# Set this variable to one to enable this option for all VMs
-use_huge_all = 0
-
-#Instead of autodetecting, override the hugetlbfs directory by setting
-#this variable
-hugetlbfs_dir = ""
-
-#############################################
-
-
-#############################################
-# ****** Do Not Modify Below this Line ******
-#############################################
-
-import sys, os, subprocess
-
-
-#List of open userspace vhost file descriptors
-fd_list = []
-
-#additional virtio device flags when using userspace vhost
-vhost_flags = [ "csum=off",
-                "gso=off",
-                "guest_tso4=off",
-                "guest_tso6=off",
-                "guest_ecn=off"
-              ]
-
-
-#############################################
-# Find the system hugefile mount point.
-# Note:
-# if multiple hugetlbfs mount points exist
-# then the first one found will be used
-#############################################
-def find_huge_mount():
-
-    if (len(hugetlbfs_dir)):
-        return hugetlbfs_dir
-
-    huge_mount = ""
-
-    if (os.access("/proc/mounts", os.F_OK)):
-        f = open("/proc/mounts", "r")
-        line = f.readline()
-        while line:
-            line_split = line.split(" ")
-            if line_split[2] == 'hugetlbfs':
-                huge_mount = line_split[1]
-                break
-            line = f.readline()
-    else:
-        print "/proc/mounts not found"
-        exit (1)
-
-    f.close
-    if len(huge_mount) == 0:
-        print "Failed to find hugetlbfs mount point"
-        exit (1)
-
-    return huge_mount
-
-
-#############################################
-# Get a userspace Vhost file descriptor
-#############################################
-def get_vhost_fd():
-
-    if (os.access(us_vhost_path, os.F_OK)):
-        fd = os.open( us_vhost_path, os.O_RDWR)
-    else:
-        print ("US-Vhost file %s not found" %us_vhost_path)
-        exit (1)
-
-    return fd
-
-
-#############################################
-# Check for vhostfd. if found then replace
-# with our own vhost fd and append any vhost
-# flags onto the end
-#############################################
-def modify_netdev_arg(arg):
-	
-    global fd_list
-    vhost_in_use = 0
-    s = ''
-    new_opts = []
-    netdev_opts = arg.split(",")
-
-    for opt in netdev_opts:
-        #check if vhost is used
-        if "vhost" == opt[:5]:
-            vhost_in_use = 1
-        else:
-            new_opts.append(opt)
-
-    #if using vhost append vhost options
-    if vhost_in_use == 1:
-        #append vhost on option
-        new_opts.append('vhost=on')
-        #append vhostfd ption
-        new_fd = get_vhost_fd()
-        new_opts.append('vhostfd=' + str(new_fd))
-        fd_list.append(new_fd)
-
-    #concatenate all options
-    for opt in new_opts:
-        if len(s) > 0:
-			s+=','
-
-        s+=opt
-
-    return s	
-
-
-#############################################
-# Main
-#############################################
-def main():
-
-    global fd_list
-    global vhost_in_use
-    new_args = []
-    num_cmd_args = len(sys.argv)
-    emul_call = ''
-    mem_prealloc_set = 0
-    mem_path_set = 0
-    num = 0;
-
-    #parse the parameters
-    while (num < num_cmd_args):
-        arg = sys.argv[num]
-
-		#Check netdev +1 parameter for vhostfd
-        if arg == '-netdev':
-            num_vhost_devs = len(fd_list)
-            new_args.append(arg)
-
-            num+=1
-            arg = sys.argv[num]
-            mod_arg = modify_netdev_arg(arg)
-            new_args.append(mod_arg)
-
-            #append vhost flags if this is a vhost device
-            # and -device is the next arg
-            # i.e -device -opt1,-opt2,...,-opt3,%vhost
-            if (num_vhost_devs < len(fd_list)):
-                num+=1
-                arg = sys.argv[num]
-                if arg == '-device':
-                    new_args.append(arg)
-                    num+=1
-                    new_arg = sys.argv[num]
-                    for flag in vhost_flags:
-                        new_arg = ''.join([new_arg,',',flag])
-                    new_args.append(new_arg)
-                else:
-                    new_args.append(arg)
-        elif arg == '-mem-prealloc':
-            mem_prealloc_set = 1
-            new_args.append(arg)
-        elif arg == '-mem-path':
-            mem_path_set = 1
-            new_args.append(arg)
-
-        else:
-            new_args.append(arg)
-
-        num+=1
-
-    #Set Qemu binary location
-    emul_call+=emul_path
-    emul_call+=" "
-
-    #Add prealloc mem options if using vhost and not already added
-    if ((len(fd_list) > 0) and (mem_prealloc_set == 0)):
-        emul_call += "-mem-prealloc "
-
-    #Add mempath mem options if using vhost and not already added
-    if ((len(fd_list) > 0) and (mem_path_set == 0)):
-        #Detect and add hugetlbfs mount point
-        mp = find_huge_mount()
-        mp = "".join(["-mem-path ", mp])
-        emul_call += mp
-        emul_call += " "
-
-
-    #add user options
-    for opt in emul_opts_user:
-        emul_call += opt
-        emul_call += " "
-
-    #Add add user vhost only options
-    if len(fd_list) > 0:
-        for opt in emul_opts_user_vhost:
-            emul_call += opt
-            emul_call += " "
-
-    #Add updated libvirt options
-    iter_args = iter(new_args)
-    #skip 1st arg i.e. call to this script
-    next(iter_args)
-    for arg in iter_args:
-        emul_call+=str(arg)
-        emul_call+= " "
-
-    #Call QEMU
-    subprocess.call(emul_call, shell=True)
-
-
-    #Close usvhost files
-    for fd in fd_list:
-        os.close(fd)
-
-
-if __name__ == "__main__":
-    main()
-
diff --git a/examples/vhost/main.c b/examples/vhost/main.c
deleted file mode 100644
index 7d9e6a2..0000000
--- a/examples/vhost/main.c
+++ /dev/null
@@ -1,3722 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <arpa/inet.h>
-#include <getopt.h>
-#include <linux/if_ether.h>
-#include <linux/if_vlan.h>
-#include <linux/virtio_net.h>
-#include <linux/virtio_ring.h>
-#include <signal.h>
-#include <stdint.h>
-#include <sys/eventfd.h>
-#include <sys/param.h>
-#include <unistd.h>
-
-#include <rte_atomic.h>
-#include <rte_cycles.h>
-#include <rte_ethdev.h>
-#include <rte_log.h>
-#include <rte_string_fns.h>
-#include <rte_malloc.h>
-
-#include "main.h"
-#include "virtio-net.h"
-#include "vhost-net-cdev.h"
-
-#define MAX_QUEUES 128
-
-/* the maximum number of external ports supported */
-#define MAX_SUP_PORTS 1
-
-/*
- * Calculate the number of buffers needed per port
- */
-#define NUM_MBUFS_PER_PORT ((MAX_QUEUES*RTE_TEST_RX_DESC_DEFAULT) +  		\
-							(num_switching_cores*MAX_PKT_BURST) +  			\
-							(num_switching_cores*RTE_TEST_TX_DESC_DEFAULT) +\
-							(num_switching_cores*MBUF_CACHE_SIZE))
-
-#define MBUF_CACHE_SIZE 128
-#define MBUF_SIZE (2048 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
-
-/*
- * No frame data buffer allocated from host are required for zero copy
- * implementation, guest will allocate the frame data buffer, and vhost
- * directly use it.
- */
-#define VIRTIO_DESCRIPTOR_LEN_ZCP 1518
-#define MBUF_SIZE_ZCP (VIRTIO_DESCRIPTOR_LEN_ZCP + sizeof(struct rte_mbuf) \
-	+ RTE_PKTMBUF_HEADROOM)
-#define MBUF_CACHE_SIZE_ZCP 0
-
-/*
- * RX and TX Prefetch, Host, and Write-back threshold values should be
- * carefully set for optimal performance. Consult the network
- * controller's datasheet and supporting DPDK documentation for guidance
- * on how these parameters should be set.
- */
-#define RX_PTHRESH 8 /* Default values of RX prefetch threshold reg. */
-#define RX_HTHRESH 8 /* Default values of RX host threshold reg. */
-#define RX_WTHRESH 4 /* Default values of RX write-back threshold reg. */
-
-/*
- * These default values are optimized for use with the Intel(R) 82599 10 GbE
- * Controller and the DPDK ixgbe PMD. Consider using other values for other
- * network controllers and/or network drivers.
- */
-#define TX_PTHRESH 36 /* Default values of TX prefetch threshold reg. */
-#define TX_HTHRESH 0  /* Default values of TX host threshold reg. */
-#define TX_WTHRESH 0  /* Default values of TX write-back threshold reg. */
-
-#define MAX_PKT_BURST 32 		/* Max burst size for RX/TX */
-#define MAX_MRG_PKT_BURST 16 	/* Max burst for merge buffers. Set to 1 due to performance issue. */
-#define BURST_TX_DRAIN_US 100 	/* TX drain every ~100us */
-
-#define BURST_RX_WAIT_US 15 	/* Defines how long we wait between retries on RX */
-#define BURST_RX_RETRIES 4		/* Number of retries on RX. */
-
-#define JUMBO_FRAME_MAX_SIZE    0x2600
-
-/* State of virtio device. */
-#define DEVICE_MAC_LEARNING 0
-#define DEVICE_RX			1
-#define DEVICE_SAFE_REMOVE	2
-
-/* Config_core_flag status definitions. */
-#define REQUEST_DEV_REMOVAL 1
-#define ACK_DEV_REMOVAL 0
-
-/* Configurable number of RX/TX ring descriptors */
-#define RTE_TEST_RX_DESC_DEFAULT 1024
-#define RTE_TEST_TX_DESC_DEFAULT 512
-
-/*
- * Need refine these 2 macros for legacy and DPDK based front end:
- * Max vring avail descriptor/entries from guest - MAX_PKT_BURST
- * And then adjust power 2.
- */
-/*
- * For legacy front end, 128 descriptors,
- * half for virtio header, another half for mbuf.
- */
-#define RTE_TEST_RX_DESC_DEFAULT_ZCP 32   /* legacy: 32, DPDK virt FE: 128. */
-#define RTE_TEST_TX_DESC_DEFAULT_ZCP 64   /* legacy: 64, DPDK virt FE: 64.  */
-
-/* Get first 4 bytes in mbuf headroom. */
-#define MBUF_HEADROOM_UINT32(mbuf) (*(uint32_t *)((uint8_t *)(mbuf) \
-		+ sizeof(struct rte_mbuf)))
-
-/* true if x is a power of 2 */
-#define POWEROF2(x) ((((x)-1) & (x)) == 0)
-
-#define INVALID_PORT_ID 0xFF
-
-/* Max number of devices. Limited by vmdq. */
-#define MAX_DEVICES 64
-
-/* Size of buffers used for snprintfs. */
-#define MAX_PRINT_BUFF 6072
-
-/* Maximum character device basename size. */
-#define MAX_BASENAME_SZ 10
-
-/* Maximum long option length for option parsing. */
-#define MAX_LONG_OPT_SZ 64
-
-/* Used to compare MAC addresses. */
-#define MAC_ADDR_CMP 0xFFFFFFFFFFFFULL
-
-/* Number of descriptors per cacheline. */
-#define DESC_PER_CACHELINE (CACHE_LINE_SIZE / sizeof(struct vring_desc))
-
-/* mask of enabled ports */
-static uint32_t enabled_port_mask = 0;
-
-/*Number of switching cores enabled*/
-static uint32_t num_switching_cores = 0;
-
-/* number of devices/queues to support*/
-static uint32_t num_queues = 0;
-uint32_t num_devices = 0;
-
-/*
- * Enable zero copy, pkts buffer will directly dma to hw descriptor,
- * disabled on default.
- */
-static uint32_t zero_copy;
-
-/* number of descriptors to apply*/
-static uint32_t num_rx_descriptor = RTE_TEST_RX_DESC_DEFAULT_ZCP;
-static uint32_t num_tx_descriptor = RTE_TEST_TX_DESC_DEFAULT_ZCP;
-
-/* max ring descriptor, ixgbe, i40e, e1000 all are 4096. */
-#define MAX_RING_DESC 4096
-
-struct vpool {
-	struct rte_mempool *pool;
-	struct rte_ring *ring;
-	uint32_t buf_size;
-} vpool_array[MAX_QUEUES+MAX_QUEUES];
-
-/* Enable VM2VM communications. If this is disabled then the MAC address compare is skipped. */
-typedef enum {
-	VM2VM_DISABLED = 0,
-	VM2VM_SOFTWARE = 1,
-	VM2VM_HARDWARE = 2,
-	VM2VM_LAST
-} vm2vm_type;
-static vm2vm_type vm2vm_mode = VM2VM_SOFTWARE;
-
-/* The type of host physical address translated from guest physical address. */
-typedef enum {
-	PHYS_ADDR_CONTINUOUS = 0,
-	PHYS_ADDR_CROSS_SUBREG = 1,
-	PHYS_ADDR_INVALID = 2,
-	PHYS_ADDR_LAST
-} hpa_type;
-
-/* Enable stats. */
-static uint32_t enable_stats = 0;
-/* Enable retries on RX. */
-static uint32_t enable_retry = 1;
-/* Specify timeout (in useconds) between retries on RX. */
-static uint32_t burst_rx_delay_time = BURST_RX_WAIT_US;
-/* Specify the number of retries on RX. */
-static uint32_t burst_rx_retry_num = BURST_RX_RETRIES;
-
-/* Character device basename. Can be set by user. */
-static char dev_basename[MAX_BASENAME_SZ] = "vhost-net";
-
-/* Charater device index. Can be set by user. */
-static uint32_t dev_index = 0;
-
-/* This can be set by the user so it is made available here. */
-extern uint64_t VHOST_FEATURES;
-
-/* Default configuration for rx and tx thresholds etc. */
-static struct rte_eth_rxconf rx_conf_default = {
-	.rx_thresh = {
-		.pthresh = RX_PTHRESH,
-		.hthresh = RX_HTHRESH,
-		.wthresh = RX_WTHRESH,
-	},
-	.rx_drop_en = 1,
-};
-
-/*
- * These default values are optimized for use with the Intel(R) 82599 10 GbE
- * Controller and the DPDK ixgbe/igb PMD. Consider using other values for other
- * network controllers and/or network drivers.
- */
-static struct rte_eth_txconf tx_conf_default = {
-	.tx_thresh = {
-		.pthresh = TX_PTHRESH,
-		.hthresh = TX_HTHRESH,
-		.wthresh = TX_WTHRESH,
-	},
-	.tx_free_thresh = 0, /* Use PMD default values */
-	.tx_rs_thresh = 0, /* Use PMD default values */
-};
-
-/* empty vmdq configuration structure. Filled in programatically */
-static struct rte_eth_conf vmdq_conf_default = {
-	.rxmode = {
-		.mq_mode        = ETH_MQ_RX_VMDQ_ONLY,
-		.split_hdr_size = 0,
-		.header_split   = 0, /**< Header Split disabled */
-		.hw_ip_checksum = 0, /**< IP checksum offload disabled */
-		.hw_vlan_filter = 0, /**< VLAN filtering disabled */
-		/*
-		 * It is necessary for 1G NIC such as I350,
-		 * this fixes bug of ipv4 forwarding in guest can't
-		 * forward pakets from one virtio dev to another virtio dev.
-		 */
-		.hw_vlan_strip  = 1, /**< VLAN strip enabled. */
-		.jumbo_frame    = 0, /**< Jumbo Frame Support disabled */
-		.hw_strip_crc   = 0, /**< CRC stripped by hardware */
-	},
-
-	.txmode = {
-		.mq_mode = ETH_MQ_TX_NONE,
-	},
-	.rx_adv_conf = {
-		/*
-		 * should be overridden separately in code with
-		 * appropriate values
-		 */
-		.vmdq_rx_conf = {
-			.nb_queue_pools = ETH_8_POOLS,
-			.enable_default_pool = 0,
-			.default_pool = 0,
-			.nb_pool_maps = 0,
-			.pool_map = {{0, 0},},
-		},
-	},
-};
-
-static unsigned lcore_ids[RTE_MAX_LCORE];
-static uint8_t ports[RTE_MAX_ETHPORTS];
-static unsigned num_ports = 0; /**< The number of ports specified in command line */
-
-static const uint16_t external_pkt_default_vlan_tag = 2000;
-const uint16_t vlan_tags[] = {
-	1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007,
-	1008, 1009, 1010, 1011,	1012, 1013, 1014, 1015,
-	1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023,
-	1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031,
-	1032, 1033, 1034, 1035, 1036, 1037, 1038, 1039,
-	1040, 1041, 1042, 1043, 1044, 1045, 1046, 1047,
-	1048, 1049, 1050, 1051, 1052, 1053, 1054, 1055,
-	1056, 1057, 1058, 1059, 1060, 1061, 1062, 1063,
-};
-
-/* ethernet addresses of ports */
-static struct ether_addr vmdq_ports_eth_addr[RTE_MAX_ETHPORTS];
-
-/* heads for the main used and free linked lists for the data path. */
-static struct virtio_net_data_ll *ll_root_used = NULL;
-static struct virtio_net_data_ll *ll_root_free = NULL;
-
-/* Array of data core structures containing information on individual core linked lists. */
-static struct lcore_info lcore_info[RTE_MAX_LCORE];
-
-/* Used for queueing bursts of TX packets. */
-struct mbuf_table {
-	unsigned len;
-	unsigned txq_id;
-	struct rte_mbuf *m_table[MAX_PKT_BURST];
-};
-
-/* TX queue for each data core. */
-struct mbuf_table lcore_tx_queue[RTE_MAX_LCORE];
-
-/* TX queue fori each virtio device for zero copy. */
-struct mbuf_table tx_queue_zcp[MAX_QUEUES];
-
-/* Vlan header struct used to insert vlan tags on TX. */
-struct vlan_ethhdr {
-	unsigned char   h_dest[ETH_ALEN];
-	unsigned char   h_source[ETH_ALEN];
-	__be16          h_vlan_proto;
-	__be16          h_vlan_TCI;
-	__be16          h_vlan_encapsulated_proto;
-};
-
-/* IPv4 Header */
-struct ipv4_hdr {
-	uint8_t  version_ihl;		/**< version and header length */
-	uint8_t  type_of_service;	/**< type of service */
-	uint16_t total_length;		/**< length of packet */
-	uint16_t packet_id;		/**< packet ID */
-	uint16_t fragment_offset;	/**< fragmentation offset */
-	uint8_t  time_to_live;		/**< time to live */
-	uint8_t  next_proto_id;		/**< protocol ID */
-	uint16_t hdr_checksum;		/**< header checksum */
-	uint32_t src_addr;		/**< source address */
-	uint32_t dst_addr;		/**< destination address */
-} __attribute__((__packed__));
-
-/* Header lengths. */
-#define VLAN_HLEN       4
-#define VLAN_ETH_HLEN   18
-
-/* Per-device statistics struct */
-struct device_statistics {
-	uint64_t tx_total;
-	rte_atomic64_t rx_total_atomic;
-	uint64_t rx_total;
-	uint64_t tx;
-	rte_atomic64_t rx_atomic;
-	uint64_t rx;
-} __rte_cache_aligned;
-struct device_statistics dev_statistics[MAX_DEVICES];
-
-/*
- * Builds up the correct configuration for VMDQ VLAN pool map
- * according to the pool & queue limits.
- */
-static inline int
-get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_devices)
-{
-	struct rte_eth_vmdq_rx_conf conf;
-	unsigned i;
-
-	memset(&conf, 0, sizeof(conf));
-	conf.nb_queue_pools = (enum rte_eth_nb_pools)num_devices;
-	conf.nb_pool_maps = num_devices;
-	conf.enable_loop_back =
-		vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back;
-
-	for (i = 0; i < conf.nb_pool_maps; i++) {
-		conf.pool_map[i].vlan_id = vlan_tags[ i ];
-		conf.pool_map[i].pools = (1UL << i);
-	}
-
-	(void)(rte_memcpy(eth_conf, &vmdq_conf_default, sizeof(*eth_conf)));
-	(void)(rte_memcpy(&eth_conf->rx_adv_conf.vmdq_rx_conf, &conf,
-		   sizeof(eth_conf->rx_adv_conf.vmdq_rx_conf)));
-	return 0;
-}
-
-/*
- * Validate the device number according to the max pool number gotten form
- * dev_info. If the device number is invalid, give the error message and
- * return -1. Each device must have its own pool.
- */
-static inline int
-validate_num_devices(uint32_t max_nb_devices)
-{
-	if (num_devices > max_nb_devices) {
-		RTE_LOG(ERR, VHOST_PORT, "invalid number of devices\n");
-		return -1;
-	}
-	return 0;
-}
-
-/*
- * Initialises a given port using global settings and with the rx buffers
- * coming from the mbuf_pool passed as parameter
- */
-static inline int
-port_init(uint8_t port)
-{
-	struct rte_eth_dev_info dev_info;
-	struct rte_eth_conf port_conf;
-	uint16_t rx_rings, tx_rings;
-	uint16_t rx_ring_size, tx_ring_size;
-	int retval;
-	uint16_t q;
-
-	/* The max pool number from dev_info will be used to validate the pool number specified in cmd line */
-	rte_eth_dev_info_get (port, &dev_info);
-
-	/*configure the number of supported virtio devices based on VMDQ limits */
-	num_devices = dev_info.max_vmdq_pools;
-	num_queues = dev_info.max_rx_queues;
-
-	if (zero_copy) {
-		rx_ring_size = num_rx_descriptor;
-		tx_ring_size = num_tx_descriptor;
-		tx_rings = dev_info.max_tx_queues;
-	} else {
-		rx_ring_size = RTE_TEST_RX_DESC_DEFAULT;
-		tx_ring_size = RTE_TEST_TX_DESC_DEFAULT;
-		tx_rings = (uint16_t)rte_lcore_count();
-	}
-
-	retval = validate_num_devices(MAX_DEVICES);
-	if (retval < 0)
-		return retval;
-
-	/* Get port configuration. */
-	retval = get_eth_conf(&port_conf, num_devices);
-	if (retval < 0)
-		return retval;
-
-	if (port >= rte_eth_dev_count()) return -1;
-
-	rx_rings = (uint16_t)num_queues,
-	/* Configure ethernet device. */
-	retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
-	if (retval != 0)
-		return retval;
-
-	/* Setup the queues. */
-	for (q = 0; q < rx_rings; q ++) {
-		retval = rte_eth_rx_queue_setup(port, q, rx_ring_size,
-						rte_eth_dev_socket_id(port), &rx_conf_default,
-						vpool_array[q].pool);
-		if (retval < 0)
-			return retval;
-	}
-	for (q = 0; q < tx_rings; q ++) {
-		retval = rte_eth_tx_queue_setup(port, q, tx_ring_size,
-						rte_eth_dev_socket_id(port), &tx_conf_default);
-		if (retval < 0)
-			return retval;
-	}
-
-	/* Start the device. */
-	retval  = rte_eth_dev_start(port);
-	if (retval < 0) {
-		RTE_LOG(ERR, VHOST_DATA, "Failed to start the device.\n");
-		return retval;
-	}
-
-	rte_eth_macaddr_get(port, &vmdq_ports_eth_addr[port]);
-	RTE_LOG(INFO, VHOST_PORT, "Max virtio devices supported: %u\n", num_devices);
-	RTE_LOG(INFO, VHOST_PORT, "Port %u MAC: %02"PRIx8" %02"PRIx8" %02"PRIx8
-			" %02"PRIx8" %02"PRIx8" %02"PRIx8"\n",
-			(unsigned)port,
-			vmdq_ports_eth_addr[port].addr_bytes[0],
-			vmdq_ports_eth_addr[port].addr_bytes[1],
-			vmdq_ports_eth_addr[port].addr_bytes[2],
-			vmdq_ports_eth_addr[port].addr_bytes[3],
-			vmdq_ports_eth_addr[port].addr_bytes[4],
-			vmdq_ports_eth_addr[port].addr_bytes[5]);
-
-	return 0;
-}
-
-/*
- * Set character device basename.
- */
-static int
-us_vhost_parse_basename(const char *q_arg)
-{
-	/* parse number string */
-
-	if (strnlen(q_arg, MAX_BASENAME_SZ) > MAX_BASENAME_SZ)
-		return -1;
-	else
-		snprintf((char*)&dev_basename, MAX_BASENAME_SZ, "%s", q_arg);
-
-	return 0;
-}
-
-/*
- * Parse the portmask provided at run time.
- */
-static int
-parse_portmask(const char *portmask)
-{
-	char *end = NULL;
-	unsigned long pm;
-
-	errno = 0;
-
-	/* parse hexadecimal string */
-	pm = strtoul(portmask, &end, 16);
-	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
-		return -1;
-
-	if (pm == 0)
-		return -1;
-
-	return pm;
-
-}
-
-/*
- * Parse num options at run time.
- */
-static int
-parse_num_opt(const char *q_arg, uint32_t max_valid_value)
-{
-	char *end = NULL;
-	unsigned long num;
-
-	errno = 0;
-
-	/* parse unsigned int string */
-	num = strtoul(q_arg, &end, 10);
-	if ((q_arg[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
-		return -1;
-
-	if (num > max_valid_value)
-		return -1;
-
-	return num;
-
-}
-
-/*
- * Display usage
- */
-static void
-us_vhost_usage(const char *prgname)
-{
-	RTE_LOG(INFO, VHOST_CONFIG, "%s [EAL options] -- -p PORTMASK\n"
-	"		--vm2vm [0|1|2]\n"
-	"		--rx_retry [0|1] --mergeable [0|1] --stats [0-N]\n"
-	"		--dev-basename <name> --dev-index [0-N]\n"
-	"		--nb-devices ND\n"
-	"		-p PORTMASK: Set mask for ports to be used by application\n"
-	"		--vm2vm [0|1|2]: disable/software(default)/hardware vm2vm comms\n"
-	"		--rx-retry [0|1]: disable/enable(default) retries on rx. Enable retry if destintation queue is full\n"
-	"		--rx-retry-delay [0-N]: timeout(in usecond) between retries on RX. This makes effect only if retries on rx enabled\n"
-	"		--rx-retry-num [0-N]: the number of retries on rx. This makes effect only if retries on rx enabled\n"
-	"		--mergeable [0|1]: disable(default)/enable RX mergeable buffers\n"
-	"		--stats [0-N]: 0: Disable stats, N: Time in seconds to print stats\n"
-	"		--dev-basename: The basename to be used for the character device.\n"
-	"		--dev-index [0-N]: Defaults to zero if not used. Index is appended to basename.\n"
-	"		--zero-copy [0|1]: disable(default)/enable rx/tx "
-			"zero copy\n"
-	"		--rx-desc-num [0-N]: the number of descriptors on rx, "
-			"used only when zero copy is enabled.\n"
-	"		--tx-desc-num [0-N]: the number of descriptors on tx, "
-			"used only when zero copy is enabled.\n",
-	       prgname);
-}
-
-/*
- * Parse the arguments given in the command line of the application.
- */
-static int
-us_vhost_parse_args(int argc, char **argv)
-{
-	int opt, ret;
-	int option_index;
-	unsigned i;
-	const char *prgname = argv[0];
-	static struct option long_option[] = {
-		{"vm2vm", required_argument, NULL, 0},
-		{"rx-retry", required_argument, NULL, 0},
-		{"rx-retry-delay", required_argument, NULL, 0},
-		{"rx-retry-num", required_argument, NULL, 0},
-		{"mergeable", required_argument, NULL, 0},
-		{"stats", required_argument, NULL, 0},
-		{"dev-basename", required_argument, NULL, 0},
-		{"dev-index", required_argument, NULL, 0},
-		{"zero-copy", required_argument, NULL, 0},
-		{"rx-desc-num", required_argument, NULL, 0},
-		{"tx-desc-num", required_argument, NULL, 0},
-		{NULL, 0, 0, 0},
-	};
-
-	/* Parse command line */
-	while ((opt = getopt_long(argc, argv, "p:",long_option, &option_index)) != EOF) {
-		switch (opt) {
-		/* Portmask */
-		case 'p':
-			enabled_port_mask = parse_portmask(optarg);
-			if (enabled_port_mask == 0) {
-				RTE_LOG(INFO, VHOST_CONFIG, "Invalid portmask\n");
-				us_vhost_usage(prgname);
-				return -1;
-			}
-			break;
-
-		case 0:
-			/* Enable/disable vm2vm comms. */
-			if (!strncmp(long_option[option_index].name, "vm2vm",
-				MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, (VM2VM_LAST - 1));
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-						"Invalid argument for "
-						"vm2vm [0|1|2]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					vm2vm_mode = (vm2vm_type)ret;
-				}
-			}
-
-			/* Enable/disable retries on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					enable_retry = ret;
-				}
-			}
-
-			/* Specify the retries delay time (in useconds) on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry-delay", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-delay [0-N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					burst_rx_delay_time = ret;
-				}
-			}
-
-			/* Specify the retries number on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-num [0-N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					burst_rx_retry_num = ret;
-				}
-			}
-
-			/* Enable/disable RX mergeable buffers. */
-			if (!strncmp(long_option[option_index].name, "mergeable", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for mergeable [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					if (ret) {
-						vmdq_conf_default.rxmode.jumbo_frame = 1;
-						vmdq_conf_default.rxmode.max_rx_pkt_len
-							= JUMBO_FRAME_MAX_SIZE;
-						VHOST_FEATURES = (1ULL << VIRTIO_NET_F_MRG_RXBUF);
-					}
-				}
-			}
-
-			/* Enable/disable stats. */
-			if (!strncmp(long_option[option_index].name, "stats", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for stats [0..N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					enable_stats = ret;
-				}
-			}
-
-			/* Set character device basename. */
-			if (!strncmp(long_option[option_index].name, "dev-basename", MAX_LONG_OPT_SZ)) {
-				if (us_vhost_parse_basename(optarg) == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device basename (Max %d characters)\n", MAX_BASENAME_SZ);
-					us_vhost_usage(prgname);
-					return -1;
-				}
-			}
-
-			/* Set character device index. */
-			if (!strncmp(long_option[option_index].name, "dev-index", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device index [0..N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else
-					dev_index = ret;
-			}
-
-			/* Enable/disable rx/tx zero copy. */
-			if (!strncmp(long_option[option_index].name,
-				"zero-copy", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-						"Invalid argument"
-						" for zero-copy [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else
-					zero_copy = ret;
-
-				if (zero_copy) {
-#ifdef RTE_MBUF_SCATTER_GATHER
-					RTE_LOG(ERR, VHOST_CONFIG, "Before running "
-					"zero copy vhost APP, please "
-					"disable RTE_MBUF_SCATTER_GATHER\n"
-					"in config file and then rebuild DPDK "
-					"core lib!\n"
-					"Otherwise please disable zero copy "
-					"flag in command line!\n");
-					return -1;
-#endif
-				}
-			}
-
-			/* Specify the descriptor number on RX. */
-			if (!strncmp(long_option[option_index].name,
-				"rx-desc-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, MAX_RING_DESC);
-				if ((ret == -1) || (!POWEROF2(ret))) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-					"Invalid argument for rx-desc-num[0-N],"
-					"power of 2 required.\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					num_rx_descriptor = ret;
-				}
-			}
-
-			/* Specify the descriptor number on TX. */
-			if (!strncmp(long_option[option_index].name,
-				"tx-desc-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, MAX_RING_DESC);
-				if ((ret == -1) || (!POWEROF2(ret))) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-					"Invalid argument for tx-desc-num [0-N],"
-					"power of 2 required.\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					num_tx_descriptor = ret;
-				}
-			}
-
-			break;
-
-			/* Invalid option - print options. */
-		default:
-			us_vhost_usage(prgname);
-			return -1;
-		}
-	}
-
-	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
-		if (enabled_port_mask & (1 << i))
-			ports[num_ports++] = (uint8_t)i;
-	}
-
-	if ((num_ports ==  0) || (num_ports > MAX_SUP_PORTS)) {
-		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
-			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
-		return -1;
-	}
-
-	if ((zero_copy == 1) && (vm2vm_mode == VM2VM_SOFTWARE)) {
-		RTE_LOG(INFO, VHOST_PORT,
-			"Vhost zero copy doesn't support software vm2vm,"
-			"please specify 'vm2vm 2' to use hardware vm2vm.\n");
-		return -1;
-	}
-
-	if ((zero_copy == 1) && (vmdq_conf_default.rxmode.jumbo_frame == 1)) {
-		RTE_LOG(INFO, VHOST_PORT,
-			"Vhost zero copy doesn't support jumbo frame,"
-			"please specify '--mergeable 0' to disable the "
-			"mergeable feature.\n");
-		return -1;
-	}
-
-	return 0;
-}
-
-/*
- * Update the global var NUM_PORTS and array PORTS according to system ports number
- * and return valid ports number
- */
-static unsigned check_ports_num(unsigned nb_ports)
-{
-	unsigned valid_num_ports = num_ports;
-	unsigned portid;
-
-	if (num_ports > nb_ports) {
-		RTE_LOG(INFO, VHOST_PORT, "\nSpecified port number(%u) exceeds total system port number(%u)\n",
-			num_ports, nb_ports);
-		num_ports = nb_ports;
-	}
-
-	for (portid = 0; portid < num_ports; portid ++) {
-		if (ports[portid] >= nb_ports) {
-			RTE_LOG(INFO, VHOST_PORT, "\nSpecified port ID(%u) exceeds max system port ID(%u)\n",
-				ports[portid], (nb_ports - 1));
-			ports[portid] = INVALID_PORT_ID;
-			valid_num_ports--;
-		}
-	}
-	return valid_num_ports;
-}
-
-/*
- * Macro to print out packet contents. Wrapped in debug define so that the
- * data path is not effected when debug is disabled.
- */
-#ifdef DEBUG
-#define PRINT_PACKET(device, addr, size, header) do {																\
-	char *pkt_addr = (char*)(addr);																					\
-	unsigned int index;																								\
-	char packet[MAX_PRINT_BUFF];																					\
-																													\
-	if ((header))																									\
-		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size));				\
-	else																											\
-		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size));				\
-	for (index = 0; index < (size); index++) {																		\
-		snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF),	\
-			"%02hhx ", pkt_addr[index]);																			\
-	}																												\
-	snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF), "\n");	\
-																													\
-	LOG_DEBUG(VHOST_DATA, "%s", packet);																					\
-} while(0)
-#else
-#define PRINT_PACKET(device, addr, size, header) do{} while(0)
-#endif
-
-/*
- * Function to convert guest physical addresses to vhost virtual addresses. This
- * is used to convert virtio buffer addresses.
- */
-static inline uint64_t __attribute__((always_inline))
-gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
-{
-	struct virtio_memory_regions *region;
-	uint32_t regionidx;
-	uint64_t vhost_va = 0;
-
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		region = &dev->mem->regions[regionidx];
-		if ((guest_pa >= region->guest_phys_address) &&
-			(guest_pa <= region->guest_phys_address_end)) {
-			vhost_va = region->address_offset + guest_pa;
-			break;
-		}
-	}
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| VVA %p\n",
-		dev->device_fh, (void*)(uintptr_t)guest_pa, (void*)(uintptr_t)vhost_va);
-
-	return vhost_va;
-}
-
-/*
- * Function to convert guest physical addresses to vhost physical addresses.
- * This is used to convert virtio buffer addresses.
- */
-static inline uint64_t __attribute__((always_inline))
-gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
-	uint32_t buf_len, hpa_type *addr_type)
-{
-	struct virtio_memory_regions_hpa *region;
-	uint32_t regionidx;
-	uint64_t vhost_pa = 0;
-
-	*addr_type = PHYS_ADDR_INVALID;
-
-	for (regionidx = 0; regionidx < dev->mem->nregions_hpa; regionidx++) {
-		region = &dev->mem->regions_hpa[regionidx];
-		if ((guest_pa >= region->guest_phys_address) &&
-			(guest_pa <= region->guest_phys_address_end)) {
-			vhost_pa = region->host_phys_addr_offset + guest_pa;
-			if (likely((guest_pa + buf_len - 1)
-				<= region->guest_phys_address_end))
-				*addr_type = PHYS_ADDR_CONTINUOUS;
-			else
-				*addr_type = PHYS_ADDR_CROSS_SUBREG;
-			break;
-		}
-	}
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| HPA %p\n",
-		dev->device_fh, (void *)(uintptr_t)guest_pa,
-		(void *)(uintptr_t)vhost_pa);
-
-	return vhost_pa;
-}
-
-/*
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtio device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue. This function works when mergeable is disabled.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *buff;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
-	uint64_t buff_addr = 0;
-	uint64_t buff_hdr_addr = 0;
-	uint32_t head[MAX_PKT_BURST], packet_len = 0;
-	uint32_t head_idx, packet_success = 0;
-	uint32_t retry = 0;
-	uint16_t avail_idx, res_cur_idx;
-	uint16_t res_base_idx, res_end_idx;
-	uint16_t free_entries;
-	uint8_t success = 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
-
-	/* As many data cores may want access to available buffers, they need to be reserved. */
-	do {
-		res_base_idx = vq->last_used_idx_res;
-		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-
-		free_entries = (avail_idx - res_base_idx);
-		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
-		if (enable_retry && unlikely(count > free_entries)) {
-			for (retry = 0; retry < burst_rx_retry_num; retry++) {
-				rte_delay_us(burst_rx_delay_time);
-				avail_idx =
-					*((volatile uint16_t *)&vq->avail->idx);
-				free_entries = (avail_idx - res_base_idx);
-				if (count <= free_entries)
-					break;
-			}
-		}
-
-		/*check that we have enough buffers*/
-		if (unlikely(count > free_entries))
-			count = free_entries;
-
-		if (count == 0)
-			return 0;
-
-		res_end_idx = res_base_idx + count;
-		/* vq->last_used_idx_res is atomically updated. */
-		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
-									res_end_idx);
-	} while (unlikely(success == 0));
-	res_cur_idx = res_base_idx;
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
-
-	/* Prefetch available ring to retrieve indexes. */
-	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (head_idx = 0; head_idx < count; head_idx++)
-		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
-
-	/*Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-
-	while (res_cur_idx != res_end_idx) {
-		/* Get descriptor from available ring */
-		desc = &vq->desc[head[packet_success]];
-
-		buff = pkts[packet_success];
-
-		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
-
-		/* Copy virtio_hdr to packet and increment buffer address */
-		buff_hdr_addr = buff_addr;
-		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-		/*
-		 * If the descriptors are chained the header and data are
-		 * placed in separate buffers.
-		 */
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc->len = vq->vhost_hlen;
-			desc = &vq->desc[desc->next];
-			/* Buffer address translation. */
-			buff_addr = gpa_to_vva(dev, desc->addr);
-			desc->len = rte_pktmbuf_data_len(buff);
-		} else {
-			buff_addr += vq->vhost_hlen;
-			desc->len = packet_len;
-		}
-
-		/* Update used ring with desc information */
-		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
-		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
-
-		/* Copy mbuf data to buffer */
-		rte_memcpy((void *)(uintptr_t)buff_addr,
-			(const void *)buff->pkt.data,
-			rte_pktmbuf_data_len(buff));
-		PRINT_PACKET(dev, (uintptr_t)buff_addr,
-			rte_pktmbuf_data_len(buff), 0);
-
-		res_cur_idx++;
-		packet_success++;
-
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
-			(const void *)&virtio_hdr, vq->vhost_hlen);
-
-		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-
-		if (res_cur_idx < res_end_idx) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success]]);
-		}
-	}
-
-	rte_compiler_barrier();
-
-	/* Wait until it's our turn to add our buffer to the used ring. */
-	while (unlikely(vq->last_used_idx != res_base_idx))
-		rte_pause();
-
-	*(volatile uint16_t *)&vq->used->idx += count;
-	vq->last_used_idx = res_end_idx;
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-	return count;
-}
-
-static inline uint32_t __attribute__((always_inline))
-copy_from_mbuf_to_vring(struct virtio_net *dev,
-	uint16_t res_base_idx, uint16_t res_end_idx,
-	struct rte_mbuf *pkt)
-{
-	uint32_t vec_idx = 0;
-	uint32_t entry_success = 0;
-	struct vhost_virtqueue *vq;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {
-		{0, 0, 0, 0, 0, 0}, 0};
-	uint16_t cur_idx = res_base_idx;
-	uint64_t vb_addr = 0;
-	uint64_t vb_hdr_addr = 0;
-	uint32_t seg_offset = 0;
-	uint32_t vb_offset = 0;
-	uint32_t seg_avail;
-	uint32_t vb_avail;
-	uint32_t cpy_len, entry_len;
-
-	if (pkt == NULL)
-		return 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| "
-		"End Index %d\n",
-		dev->device_fh, cur_idx, res_end_idx);
-
-	/*
-	 * Convert from gpa to vva
-	 * (guest physical addr -> vhost virtual addr)
-	 */
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	vb_addr =
-		gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
-	vb_hdr_addr = vb_addr;
-
-	/* Prefetch buffer address. */
-	rte_prefetch0((void *)(uintptr_t)vb_addr);
-
-	virtio_hdr.num_buffers = res_end_idx - res_base_idx;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n",
-		dev->device_fh, virtio_hdr.num_buffers);
-
-	rte_memcpy((void *)(uintptr_t)vb_hdr_addr,
-		(const void *)&virtio_hdr, vq->vhost_hlen);
-
-	PRINT_PACKET(dev, (uintptr_t)vb_hdr_addr, vq->vhost_hlen, 1);
-
-	seg_avail = rte_pktmbuf_data_len(pkt);
-	vb_offset = vq->vhost_hlen;
-	vb_avail =
-		vq->buf_vec[vec_idx].buf_len - vq->vhost_hlen;
-
-	entry_len = vq->vhost_hlen;
-
-	if (vb_avail == 0) {
-		uint32_t desc_idx =
-			vq->buf_vec[vec_idx].desc_idx;
-		vq->desc[desc_idx].len = vq->vhost_hlen;
-
-		if ((vq->desc[desc_idx].flags
-			& VRING_DESC_F_NEXT) == 0) {
-			/* Update used ring with desc information */
-			vq->used->ring[cur_idx & (vq->size - 1)].id
-				= vq->buf_vec[vec_idx].desc_idx;
-			vq->used->ring[cur_idx & (vq->size - 1)].len
-				= entry_len;
-
-			entry_len = 0;
-			cur_idx++;
-			entry_success++;
-		}
-
-		vec_idx++;
-		vb_addr =
-			gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
-
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)vb_addr);
-		vb_offset = 0;
-		vb_avail = vq->buf_vec[vec_idx].buf_len;
-	}
-
-	cpy_len = RTE_MIN(vb_avail, seg_avail);
-
-	while (cpy_len > 0) {
-		/* Copy mbuf data to vring buffer */
-		rte_memcpy((void *)(uintptr_t)(vb_addr + vb_offset),
-			(const void *)(rte_pktmbuf_mtod(pkt, char*) + seg_offset),
-			cpy_len);
-
-		PRINT_PACKET(dev,
-			(uintptr_t)(vb_addr + vb_offset),
-			cpy_len, 0);
-
-		seg_offset += cpy_len;
-		vb_offset += cpy_len;
-		seg_avail -= cpy_len;
-		vb_avail -= cpy_len;
-		entry_len += cpy_len;
-
-		if (seg_avail != 0) {
-			/*
-			 * The virtio buffer in this vring
-			 * entry reach to its end.
-			 * But the segment doesn't complete.
-			 */
-			if ((vq->desc[vq->buf_vec[vec_idx].desc_idx].flags &
-				VRING_DESC_F_NEXT) == 0) {
-				/* Update used ring with desc information */
-				vq->used->ring[cur_idx & (vq->size - 1)].id
-					= vq->buf_vec[vec_idx].desc_idx;
-				vq->used->ring[cur_idx & (vq->size - 1)].len
-					= entry_len;
-				entry_len = 0;
-				cur_idx++;
-				entry_success++;
-			}
-
-			vec_idx++;
-			vb_addr = gpa_to_vva(dev,
-				vq->buf_vec[vec_idx].buf_addr);
-			vb_offset = 0;
-			vb_avail = vq->buf_vec[vec_idx].buf_len;
-			cpy_len = RTE_MIN(vb_avail, seg_avail);
-		} else {
-			/*
-			 * This current segment complete, need continue to
-			 * check if the whole packet complete or not.
-			 */
-			pkt = pkt->pkt.next;
-			if (pkt != NULL) {
-				/*
-				 * There are more segments.
-				 */
-				if (vb_avail == 0) {
-					/*
-					 * This current buffer from vring is
-					 * used up, need fetch next buffer
-					 * from buf_vec.
-					 */
-					uint32_t desc_idx =
-						vq->buf_vec[vec_idx].desc_idx;
-					vq->desc[desc_idx].len = vb_offset;
-
-					if ((vq->desc[desc_idx].flags &
-						VRING_DESC_F_NEXT) == 0) {
-						uint16_t wrapped_idx =
-							cur_idx & (vq->size - 1);
-						/*
-						 * Update used ring with the
-						 * descriptor information
-						 */
-						vq->used->ring[wrapped_idx].id
-							= desc_idx;
-						vq->used->ring[wrapped_idx].len
-							= entry_len;
-						entry_success++;
-						entry_len = 0;
-						cur_idx++;
-					}
-
-					/* Get next buffer from buf_vec. */
-					vec_idx++;
-					vb_addr = gpa_to_vva(dev,
-						vq->buf_vec[vec_idx].buf_addr);
-					vb_avail =
-						vq->buf_vec[vec_idx].buf_len;
-					vb_offset = 0;
-				}
-
-				seg_offset = 0;
-				seg_avail = rte_pktmbuf_data_len(pkt);
-				cpy_len = RTE_MIN(vb_avail, seg_avail);
-			} else {
-				/*
-				 * This whole packet completes.
-				 */
-				uint32_t desc_idx =
-					vq->buf_vec[vec_idx].desc_idx;
-				vq->desc[desc_idx].len = vb_offset;
-
-				while (vq->desc[desc_idx].flags &
-					VRING_DESC_F_NEXT) {
-					desc_idx = vq->desc[desc_idx].next;
-					 vq->desc[desc_idx].len = 0;
-				}
-
-				/* Update used ring with desc information */
-				vq->used->ring[cur_idx & (vq->size - 1)].id
-					= vq->buf_vec[vec_idx].desc_idx;
-				vq->used->ring[cur_idx & (vq->size - 1)].len
-					= entry_len;
-				entry_len = 0;
-				cur_idx++;
-				entry_success++;
-				seg_avail = 0;
-				cpy_len = RTE_MIN(vb_avail, seg_avail);
-			}
-		}
-	}
-
-	return entry_success;
-}
-
-/*
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtio device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue. This function works for mergeable RX.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_merge_rx(struct virtio_net *dev, struct rte_mbuf **pkts,
-	uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	uint32_t pkt_idx = 0, entry_success = 0;
-	uint32_t retry = 0;
-	uint16_t avail_idx, res_cur_idx;
-	uint16_t res_base_idx, res_end_idx;
-	uint8_t success = 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_rx()\n",
-		dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
-
-	if (count == 0)
-		return 0;
-
-	for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
-		uint32_t secure_len = 0;
-		uint16_t need_cnt;
-		uint32_t vec_idx = 0;
-		uint32_t pkt_len = pkts[pkt_idx]->pkt.pkt_len + vq->vhost_hlen;
-		uint16_t i, id;
-
-		do {
-			/*
-			 * As many data cores may want access to available
-			 * buffers, they need to be reserved.
-			 */
-			res_base_idx = vq->last_used_idx_res;
-			res_cur_idx = res_base_idx;
-
-			do {
-				avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-				if (unlikely(res_cur_idx == avail_idx)) {
-					/*
-					 * If retry is enabled and the queue is
-					 * full then we wait and retry to avoid
-					 * packet loss.
-					 */
-					if (enable_retry) {
-						uint8_t cont = 0;
-						for (retry = 0; retry < burst_rx_retry_num; retry++) {
-							rte_delay_us(burst_rx_delay_time);
-							avail_idx =
-								*((volatile uint16_t *)&vq->avail->idx);
-							if (likely(res_cur_idx != avail_idx)) {
-								cont = 1;
-								break;
-							}
-						}
-						if (cont == 1)
-							continue;
-					}
-
-					LOG_DEBUG(VHOST_DATA,
-						"(%"PRIu64") Failed "
-						"to get enough desc from "
-						"vring\n",
-						dev->device_fh);
-					return pkt_idx;
-				} else {
-					uint16_t wrapped_idx =
-						(res_cur_idx) & (vq->size - 1);
-					uint32_t idx =
-						vq->avail->ring[wrapped_idx];
-					uint8_t next_desc;
-
-					do {
-						next_desc = 0;
-						secure_len += vq->desc[idx].len;
-						if (vq->desc[idx].flags &
-							VRING_DESC_F_NEXT) {
-							idx = vq->desc[idx].next;
-							next_desc = 1;
-						}
-					} while (next_desc);
-
-					res_cur_idx++;
-				}
-			} while (pkt_len > secure_len);
-
-			/* vq->last_used_idx_res is atomically updated. */
-			success = rte_atomic16_cmpset(&vq->last_used_idx_res,
-							res_base_idx,
-							res_cur_idx);
-		} while (success == 0);
-
-		id = res_base_idx;
-		need_cnt = res_cur_idx - res_base_idx;
-
-		for (i = 0; i < need_cnt; i++, id++) {
-			uint16_t wrapped_idx = id & (vq->size - 1);
-			uint32_t idx = vq->avail->ring[wrapped_idx];
-			uint8_t next_desc;
-			do {
-				next_desc = 0;
-				vq->buf_vec[vec_idx].buf_addr =
-					vq->desc[idx].addr;
-				vq->buf_vec[vec_idx].buf_len =
-					vq->desc[idx].len;
-				vq->buf_vec[vec_idx].desc_idx = idx;
-				vec_idx++;
-
-				if (vq->desc[idx].flags & VRING_DESC_F_NEXT) {
-					idx = vq->desc[idx].next;
-					next_desc = 1;
-				}
-			} while (next_desc);
-		}
-
-		res_end_idx = res_cur_idx;
-
-		entry_success = copy_from_mbuf_to_vring(dev, res_base_idx,
-			res_end_idx, pkts[pkt_idx]);
-
-		rte_compiler_barrier();
-
-		/*
-		 * Wait until it's our turn to add our buffer
-		 * to the used ring.
-		 */
-		while (unlikely(vq->last_used_idx != res_base_idx))
-			rte_pause();
-
-		*(volatile uint16_t *)&vq->used->idx += entry_success;
-		vq->last_used_idx = res_end_idx;
-
-		/* Kick the guest if necessary. */
-		if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-			eventfd_write((int)vq->kickfd, 1);
-	}
-
-	return count;
-}
-
-/*
- * Compares a packet destination MAC address to a device MAC address.
- */
-static inline int __attribute__((always_inline))
-ether_addr_cmp(struct ether_addr *ea, struct ether_addr *eb)
-{
-	return (((*(uint64_t *)ea ^ *(uint64_t *)eb) & MAC_ADDR_CMP) == 0);
-}
-
-/*
- * This function learns the MAC address of the device and registers this along with a
- * vlan tag to a VMDQ.
- */
-static int
-link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
-{
-	struct ether_hdr *pkt_hdr;
-	struct virtio_net_data_ll *dev_ll;
-	int i, ret;
-
-	/* Learn MAC address of guest device from packet */
-	pkt_hdr = (struct ether_hdr *)m->pkt.data;
-
-	dev_ll = ll_root_used;
-
-	while (dev_ll != NULL) {
-		if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->dev->mac_address)) {
-			RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") WARNING: This device is using an existing MAC address and has not been registered.\n", dev->device_fh);
-			return -1;
-		}
-		dev_ll = dev_ll->next;
-	}
-
-	for (i = 0; i < ETHER_ADDR_LEN; i++)
-		dev->mac_address.addr_bytes[i] = pkt_hdr->s_addr.addr_bytes[i];
-
-	/* vlan_tag currently uses the device_id. */
-	dev->vlan_tag = vlan_tags[dev->device_fh];
-
-	/* Print out VMDQ registration info. */
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") MAC_ADDRESS %02x:%02x:%02x:%02x:%02x:%02x and VLAN_TAG %d registered\n",
-		dev->device_fh,
-		dev->mac_address.addr_bytes[0], dev->mac_address.addr_bytes[1],
-		dev->mac_address.addr_bytes[2], dev->mac_address.addr_bytes[3],
-		dev->mac_address.addr_bytes[4], dev->mac_address.addr_bytes[5],
-		dev->vlan_tag);
-
-	/* Register the MAC address. */
-	ret = rte_eth_dev_mac_addr_add(ports[0], &dev->mac_address, (uint32_t)dev->device_fh);
-	if (ret)
-		RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Failed to add device MAC address to VMDQ\n",
-					dev->device_fh);
-
-	/* Enable stripping of the vlan tag as we handle routing. */
-	rte_eth_dev_set_vlan_strip_on_queue(ports[0], (uint16_t)dev->vmdq_rx_q, 1);
-
-	/* Set device as ready for RX. */
-	dev->ready = DEVICE_RX;
-
-	return 0;
-}
-
-/*
- * Removes MAC address and vlan tag from VMDQ. Ensures that nothing is adding buffers to the RX
- * queue before disabling RX on the device.
- */
-static inline void
-unlink_vmdq(struct virtio_net *dev)
-{
-	unsigned i = 0;
-	unsigned rx_count;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-
-	if (dev->ready == DEVICE_RX) {
-		/*clear MAC and VLAN settings*/
-		rte_eth_dev_mac_addr_remove(ports[0], &dev->mac_address);
-		for (i = 0; i < 6; i++)
-			dev->mac_address.addr_bytes[i] = 0;
-
-		dev->vlan_tag = 0;
-
-		/*Clear out the receive buffers*/
-		rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-
-		while (rx_count) {
-			for (i = 0; i < rx_count; i++)
-				rte_pktmbuf_free(pkts_burst[i]);
-
-			rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-		}
-
-		dev->ready = DEVICE_MAC_LEARNING;
-	}
-}
-
-/*
- * Check if the packet destination MAC address is for a local device. If so then put
- * the packet on that devices RX queue. If not then return.
- */
-static inline unsigned __attribute__((always_inline))
-virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
-{
-	struct virtio_net_data_ll *dev_ll;
-	struct ether_hdr *pkt_hdr;
-	uint64_t ret = 0;
-
-	pkt_hdr = (struct ether_hdr *)m->pkt.data;
-
-	/*get the used devices list*/
-	dev_ll = ll_root_used;
-
-	while (dev_ll != NULL) {
-		if ((dev_ll->dev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
-				          &dev_ll->dev->mac_address)) {
-
-			/* Drop the packet if the TX packet is destined for the TX device. */
-			if (dev_ll->dev->device_fh == dev->device_fh) {
-				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
-							dev_ll->dev->device_fh);
-				return 0;
-			}
-
-
-			LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", dev_ll->dev->device_fh);
-
-			if (dev_ll->dev->remove) {
-				/*drop the packet if the device is marked for removal*/
-				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", dev_ll->dev->device_fh);
-			} else {
-				uint32_t mergeable =
-					dev_ll->dev->features &
-					(1 << VIRTIO_NET_F_MRG_RXBUF);
-
-				/*send the packet to the local virtio device*/
-				if (likely(mergeable == 0))
-					ret = virtio_dev_rx(dev_ll->dev, &m, 1);
-				else
-					ret = virtio_dev_merge_rx(dev_ll->dev,
-						&m, 1);
-
-				if (enable_stats) {
-					rte_atomic64_add(
-					&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
-					1);
-					rte_atomic64_add(
-					&dev_statistics[dev_ll->dev->device_fh].rx_atomic,
-					ret);
-					dev_statistics[dev->device_fh].tx_total++;
-					dev_statistics[dev->device_fh].tx += ret;
-				}
-			}
-
-			return 0;
-		}
-		dev_ll = dev_ll->next;
-	}
-
-	return -1;
-}
-
-/*
- * This function routes the TX packet to the correct interface. This may be a local device
- * or the physical port.
- */
-static inline void __attribute__((always_inline))
-virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *mbuf_pool, uint16_t vlan_tag)
-{
-	struct mbuf_table *tx_q;
-	struct vlan_ethhdr *vlan_hdr;
-	struct rte_mbuf **m_table;
-	struct rte_mbuf *mbuf, *prev;
-	unsigned len, ret, offset = 0;
-	const uint16_t lcore_id = rte_lcore_id();
-	struct virtio_net_data_ll *dev_ll = ll_root_used;
-	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
-
-	/*check if destination is local VM*/
-	if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(dev, m) == 0))
-		return;
-
-	if (vm2vm_mode == VM2VM_HARDWARE) {
-		while (dev_ll != NULL) {
-			if ((dev_ll->dev->ready == DEVICE_RX)
-				&& ether_addr_cmp(&(pkt_hdr->d_addr),
-				&dev_ll->dev->mac_address)) {
-				/*
-				 * Drop the packet if the TX packet is
-				 * destined for the TX device.
-				 */
-				if (dev_ll->dev->device_fh == dev->device_fh) {
-					LOG_DEBUG(VHOST_DATA,
-					"(%"PRIu64") TX: Source and destination"
-					" MAC addresses are the same. Dropping "
-					"packet.\n",
-					dev_ll->dev->device_fh);
-					return;
-				}
-				offset = 4;
-				vlan_tag =
-				(uint16_t)
-				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
-
-				LOG_DEBUG(VHOST_DATA,
-				"(%"PRIu64") TX: pkt to local VM device id:"
-				"(%"PRIu64") vlan tag: %d.\n",
-				dev->device_fh, dev_ll->dev->device_fh,
-				vlan_tag);
-
-				break;
-			}
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is external\n", dev->device_fh);
-
-	/*Add packet to the port tx queue*/
-	tx_q = &lcore_tx_queue[lcore_id];
-	len = tx_q->len;
-
-	/* Allocate an mbuf and populate the structure. */
-	mbuf = rte_pktmbuf_alloc(mbuf_pool);
-	if (unlikely(mbuf == NULL)) {
-		RTE_LOG(ERR, VHOST_DATA,
-			"Failed to allocate memory for mbuf.\n");
-		return;
-	}
-
-	mbuf->pkt.data_len = m->pkt.data_len + VLAN_HLEN + offset;
-	mbuf->pkt.pkt_len = m->pkt.pkt_len + VLAN_HLEN + offset;
-	mbuf->pkt.nb_segs = m->pkt.nb_segs;
-
-	/* Copy ethernet header to mbuf. */
-	rte_memcpy((void*)mbuf->pkt.data, (const void*)m->pkt.data, ETH_HLEN);
-
-
-	/* Setup vlan header. Bytes need to be re-ordered for network with htons()*/
-	vlan_hdr = (struct vlan_ethhdr *) mbuf->pkt.data;
-	vlan_hdr->h_vlan_encapsulated_proto = vlan_hdr->h_vlan_proto;
-	vlan_hdr->h_vlan_proto = htons(ETH_P_8021Q);
-	vlan_hdr->h_vlan_TCI = htons(vlan_tag);
-
-	/* Copy the remaining packet contents to the mbuf. */
-	rte_memcpy((void*) ((uint8_t*)mbuf->pkt.data + VLAN_ETH_HLEN),
-		(const void*) ((uint8_t*)m->pkt.data + ETH_HLEN), (m->pkt.data_len - ETH_HLEN));
-
-	/* Copy the remaining segments for the whole packet. */
-	prev = mbuf;
-	while (m->pkt.next) {
-		/* Allocate an mbuf and populate the structure. */
-		struct rte_mbuf *next_mbuf = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(next_mbuf == NULL)) {
-			rte_pktmbuf_free(mbuf);
-			RTE_LOG(ERR, VHOST_DATA,
-				"Failed to allocate memory for mbuf.\n");
-			return;
-		}
-
-		m = m->pkt.next;
-		prev->pkt.next = next_mbuf;
-		prev = next_mbuf;
-		next_mbuf->pkt.data_len = m->pkt.data_len;
-
-		/* Copy data to next mbuf. */
-		rte_memcpy(rte_pktmbuf_mtod(next_mbuf, void *),
-			rte_pktmbuf_mtod(m, const void *), m->pkt.data_len);
-	}
-
-	tx_q->m_table[len] = mbuf;
-	len++;
-	if (enable_stats) {
-		dev_statistics[dev->device_fh].tx_total++;
-		dev_statistics[dev->device_fh].tx++;
-	}
-
-	if (unlikely(len == MAX_PKT_BURST)) {
-		m_table = (struct rte_mbuf **)tx_q->m_table;
-		ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
-		/* Free any buffers not handled by TX and update the port stats. */
-		if (unlikely(ret < len)) {
-			do {
-				rte_pktmbuf_free(m_table[ret]);
-			} while (++ret < len);
-		}
-
-		len = 0;
-	}
-
-	tx_q->len = len;
-	return;
-}
-
-static inline void __attribute__((always_inline))
-virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
-{
-	struct rte_mbuf m;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t buff_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t used_idx;
-	uint32_t i;
-	uint16_t free_entries, packet_success = 0;
-	uint16_t avail_idx;
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	/*get the number of free entries in the ring*/
-	free_entries = (avail_idx - vq->last_used_idx);
-
-	/* Limit to MAX_PKT_BURST. */
-	if (free_entries > MAX_PKT_BURST)
-		free_entries = MAX_PKT_BURST;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (packet_success < free_entries) {
-		desc = &vq->desc[head[packet_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
-
-		used_idx = vq->last_used_idx & (vq->size - 1);
-
-		if (packet_success < (free_entries - 1)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success+1]]);
-			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
-		}
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[packet_success];
-		vq->used->ring[used_idx].len = 0;
-
-		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
-		m.pkt.data_len = desc->len;
-		m.pkt.pkt_len = desc->len;
-		m.pkt.data = (void*)(uintptr_t)buff_addr;
-
-		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
-
-		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
-				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
-				packet_success += free_entries;
-				vq->last_used_idx += packet_success;
-				break;
-			}
-		}
-		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
-
-		vq->last_used_idx++;
-		packet_success++;
-	}
-
-	rte_compiler_barrier();
-	vq->used->idx += packet_success;
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-}
-
-/* This function works for TX packets with mergeable feature enabled. */
-static inline void __attribute__((always_inline))
-virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool)
-{
-	struct rte_mbuf *m, *prev;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t vb_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t used_idx;
-	uint32_t i;
-	uint16_t free_entries, entry_success = 0;
-	uint16_t avail_idx;
-	uint32_t buf_size = MBUF_SIZE - (sizeof(struct rte_mbuf)
-			+ RTE_PKTMBUF_HEADROOM);
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_tx()\n",
-		dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	/*get the number of free entries in the ring*/
-	free_entries = (avail_idx - vq->last_used_idx);
-
-	/* Limit to MAX_PKT_BURST. */
-	free_entries = RTE_MIN(free_entries, MAX_PKT_BURST);
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
-		dev->device_fh, free_entries);
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[entry_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (entry_success < free_entries) {
-		uint32_t vb_avail, vb_offset;
-		uint32_t seg_avail, seg_offset;
-		uint32_t cpy_len;
-		uint32_t seg_num = 0;
-		struct rte_mbuf *cur;
-		uint8_t alloc_err = 0;
-
-		desc = &vq->desc[head[entry_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		vb_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)vb_addr);
-
-		used_idx = vq->last_used_idx & (vq->size - 1);
-
-		if (entry_success < (free_entries - 1)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[entry_success+1]]);
-			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
-		}
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[entry_success];
-		vq->used->ring[used_idx].len = 0;
-
-		vb_offset = 0;
-		vb_avail = desc->len;
-		seg_offset = 0;
-		seg_avail = buf_size;
-		cpy_len = RTE_MIN(vb_avail, seg_avail);
-
-		PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
-
-		/* Allocate an mbuf and populate the structure. */
-		m = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(m == NULL)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"Failed to allocate memory for mbuf.\n");
-			return;
-		}
-
-		seg_num++;
-		cur = m;
-		prev = m;
-		while (cpy_len != 0) {
-			rte_memcpy((void *)(rte_pktmbuf_mtod(cur, char *) + seg_offset),
-				(void *)((uintptr_t)(vb_addr + vb_offset)),
-				cpy_len);
-
-			seg_offset += cpy_len;
-			vb_offset += cpy_len;
-			vb_avail -= cpy_len;
-			seg_avail -= cpy_len;
-
-			if (vb_avail != 0) {
-				/*
-				 * The segment reachs to its end,
-				 * while the virtio buffer in TX vring has
-				 * more data to be copied.
-				 */
-				cur->pkt.data_len = seg_offset;
-				m->pkt.pkt_len += seg_offset;
-				/* Allocate mbuf and populate the structure. */
-				cur = rte_pktmbuf_alloc(mbuf_pool);
-				if (unlikely(cur == NULL)) {
-					RTE_LOG(ERR, VHOST_DATA, "Failed to "
-						"allocate memory for mbuf.\n");
-					rte_pktmbuf_free(m);
-					alloc_err = 1;
-					break;
-				}
-
-				seg_num++;
-				prev->pkt.next = cur;
-				prev = cur;
-				seg_offset = 0;
-				seg_avail = buf_size;
-			} else {
-				if (desc->flags & VRING_DESC_F_NEXT) {
-					/*
-					 * There are more virtio buffers in
-					 * same vring entry need to be copied.
-					 */
-					if (seg_avail == 0) {
-						/*
-						 * The current segment hasn't
-						 * room to accomodate more
-						 * data.
-						 */
-						cur->pkt.data_len = seg_offset;
-						m->pkt.pkt_len += seg_offset;
-						/*
-						 * Allocate an mbuf and
-						 * populate the structure.
-						 */
-						cur = rte_pktmbuf_alloc(mbuf_pool);
-						if (unlikely(cur == NULL)) {
-							RTE_LOG(ERR,
-								VHOST_DATA,
-								"Failed to "
-								"allocate memory "
-								"for mbuf\n");
-							rte_pktmbuf_free(m);
-							alloc_err = 1;
-							break;
-						}
-						seg_num++;
-						prev->pkt.next = cur;
-						prev = cur;
-						seg_offset = 0;
-						seg_avail = buf_size;
-					}
-
-					desc = &vq->desc[desc->next];
-
-					/* Buffer address translation. */
-					vb_addr = gpa_to_vva(dev, desc->addr);
-					/* Prefetch buffer address. */
-					rte_prefetch0((void *)(uintptr_t)vb_addr);
-					vb_offset = 0;
-					vb_avail = desc->len;
-
-					PRINT_PACKET(dev, (uintptr_t)vb_addr,
-						desc->len, 0);
-				} else {
-					/* The whole packet completes. */
-					cur->pkt.data_len = seg_offset;
-					m->pkt.pkt_len += seg_offset;
-					vb_avail = 0;
-				}
-			}
-
-			cpy_len = RTE_MIN(vb_avail, seg_avail);
-		}
-
-		if (unlikely(alloc_err == 1))
-			break;
-
-		m->pkt.nb_segs = seg_num;
-
-		/*
-		 * If this is the first received packet we need to learn
-		 * the MAC and setup VMDQ
-		 */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, m) == -1)) {
-				/*
-				 * Discard frame if device is scheduled for
-				 * removal or a duplicate MAC address is found.
-				 */
-				entry_success = free_entries;
-				vq->last_used_idx += entry_success;
-				rte_pktmbuf_free(m);
-				break;
-			}
-		}
-
-		virtio_tx_route(dev, m, mbuf_pool, (uint16_t)dev->device_fh);
-		vq->last_used_idx++;
-		entry_success++;
-		rte_pktmbuf_free(m);
-	}
-
-	rte_compiler_barrier();
-	vq->used->idx += entry_success;
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-}
-
-/*
- * This function is called by each data core. It handles all RX/TX registered with the
- * core. For TX the specific lcore linked list is used. For RX, MAC addresses are compared
- * with all devices in the main linked list.
- */
-static int
-switch_worker(__attribute__((unused)) void *arg)
-{
-	struct rte_mempool *mbuf_pool = arg;
-	struct virtio_net *dev = NULL;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-	struct virtio_net_data_ll *dev_ll;
-	struct mbuf_table *tx_q;
-	volatile struct lcore_ll_info *lcore_ll;
-	const uint64_t drain_tsc = (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S * BURST_TX_DRAIN_US;
-	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
-	unsigned ret, i;
-	const uint16_t lcore_id = rte_lcore_id();
-	const uint16_t num_cores = (uint16_t)rte_lcore_count();
-	uint16_t rx_count = 0;
-	uint32_t mergeable = 0;
-
-	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
-	lcore_ll = lcore_info[lcore_id].lcore_ll;
-	prev_tsc = 0;
-
-	tx_q = &lcore_tx_queue[lcore_id];
-	for (i = 0; i < num_cores; i ++) {
-		if (lcore_ids[i] == lcore_id) {
-			tx_q->txq_id = i;
-			break;
-		}
-	}
-
-	while(1) {
-		cur_tsc = rte_rdtsc();
-		/*
-		 * TX burst queue drain
-		 */
-		diff_tsc = cur_tsc - prev_tsc;
-		if (unlikely(diff_tsc > drain_tsc)) {
-
-			if (tx_q->len) {
-				LOG_DEBUG(VHOST_DATA, "TX queue drained after timeout with burst size %u \n", tx_q->len);
-
-				/*Tx any packets in the queue*/
-				ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id,
-									   (struct rte_mbuf **)tx_q->m_table,
-									   (uint16_t)tx_q->len);
-				if (unlikely(ret < tx_q->len)) {
-					do {
-						rte_pktmbuf_free(tx_q->m_table[ret]);
-					} while (++ret < tx_q->len);
-				}
-
-				tx_q->len = 0;
-			}
-
-			prev_tsc = cur_tsc;
-
-		}
-
-		rte_prefetch0(lcore_ll->ll_root_used);
-		/*
-		 * Inform the configuration core that we have exited the linked list and that no devices are
-		 * in use if requested.
-		 */
-		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
-			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-
-		/*
-		 * Process devices
-		 */
-		dev_ll = lcore_ll->ll_root_used;
-
-		while (dev_ll != NULL) {
-			/*get virtio device ID*/
-			dev = dev_ll->dev;
-			mergeable =
-				dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
-
-			if (dev->remove) {
-				dev_ll = dev_ll->next;
-				unlink_vmdq(dev);
-				dev->ready = DEVICE_SAFE_REMOVE;
-				continue;
-			}
-			if (likely(dev->ready == DEVICE_RX)) {
-				/*Handle guest RX*/
-				rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-
-				if (rx_count) {
-					if (likely(mergeable == 0))
-						ret_count =
-							virtio_dev_rx(dev,
-							pkts_burst, rx_count);
-					else
-						ret_count =
-							virtio_dev_merge_rx(dev,
-							pkts_burst, rx_count);
-
-					if (enable_stats) {
-						rte_atomic64_add(
-						&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
-						rx_count);
-						rte_atomic64_add(
-						&dev_statistics[dev_ll->dev->device_fh].rx_atomic, ret_count);
-					}
-					while (likely(rx_count)) {
-						rx_count--;
-						rte_pktmbuf_free(pkts_burst[rx_count]);
-					}
-
-				}
-			}
-
-			if (!dev->remove) {
-				/*Handle guest TX*/
-				if (likely(mergeable == 0))
-					virtio_dev_tx(dev, mbuf_pool);
-				else
-					virtio_dev_merge_tx(dev, mbuf_pool);
-			}
-
-			/*move to the next device in the list*/
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	return 0;
-}
-
-/*
- * This function gets available ring number for zero copy rx.
- * Only one thread will call this funciton for a paticular virtio device,
- * so, it is designed as non-thread-safe function.
- */
-static inline uint32_t __attribute__((always_inline))
-get_available_ring_num_zcp(struct virtio_net *dev)
-{
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
-	uint16_t avail_idx;
-
-	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-	return (uint32_t)(avail_idx - vq->last_used_idx_res);
-}
-
-/*
- * This function gets available ring index for zero copy rx,
- * it will retry 'burst_rx_retry_num' times till it get enough ring index.
- * Only one thread will call this funciton for a paticular virtio device,
- * so, it is designed as non-thread-safe function.
- */
-static inline uint32_t __attribute__((always_inline))
-get_available_ring_index_zcp(struct virtio_net *dev,
-	uint16_t *res_base_idx, uint32_t count)
-{
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
-	uint16_t avail_idx;
-	uint32_t retry = 0;
-	uint16_t free_entries;
-
-	*res_base_idx = vq->last_used_idx_res;
-	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-	free_entries = (avail_idx - *res_base_idx);
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") in get_available_ring_index_zcp: "
-			"avail idx: %d, "
-			"res base idx:%d, free entries:%d\n",
-			dev->device_fh, avail_idx, *res_base_idx,
-			free_entries);
-
-	/*
-	 * If retry is enabled and the queue is full then we wait
-	 * and retry to avoid packet loss.
-	 */
-	if (enable_retry && unlikely(count > free_entries)) {
-		for (retry = 0; retry < burst_rx_retry_num; retry++) {
-			rte_delay_us(burst_rx_delay_time);
-			avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-			free_entries = (avail_idx - *res_base_idx);
-			if (count <= free_entries)
-				break;
-		}
-	}
-
-	/*check that we have enough buffers*/
-	if (unlikely(count > free_entries))
-		count = free_entries;
-
-	if (unlikely(count == 0)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") Fail in get_available_ring_index_zcp: "
-			"avail idx: %d, res base idx:%d, free entries:%d\n",
-			dev->device_fh, avail_idx,
-			*res_base_idx, free_entries);
-		return 0;
-	}
-
-	vq->last_used_idx_res = *res_base_idx + count;
-
-	return count;
-}
-
-/*
- * This function put descriptor back to used list.
- */
-static inline void __attribute__((always_inline))
-put_desc_to_used_list_zcp(struct vhost_virtqueue *vq, uint16_t desc_idx)
-{
-	uint16_t res_cur_idx = vq->last_used_idx;
-	vq->used->ring[res_cur_idx & (vq->size - 1)].id = (uint32_t)desc_idx;
-	vq->used->ring[res_cur_idx & (vq->size - 1)].len = 0;
-	rte_compiler_barrier();
-	*(volatile uint16_t *)&vq->used->idx += 1;
-	vq->last_used_idx += 1;
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-}
-
-/*
- * This function get available descriptor from vitio vring and un-attached mbuf
- * from vpool->ring, and then attach them together. It needs adjust the offset
- * for buff_addr and phys_addr accroding to PMD implementation, otherwise the
- * frame data may be put to wrong location in mbuf.
- */
-static inline void __attribute__((always_inline))
-attach_rxmbuf_zcp(struct virtio_net *dev)
-{
-	uint16_t res_base_idx, desc_idx;
-	uint64_t buff_addr, phys_addr;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *mbuf = NULL;
-	struct vpool *vpool;
-	hpa_type addr_type;
-
-	vpool = &vpool_array[dev->vmdq_rx_q];
-	vq = dev->virtqueue[VIRTIO_RXQ];
-
-	do {
-		if (unlikely(get_available_ring_index_zcp(dev, &res_base_idx,
-				1) != 1))
-			return;
-		desc_idx = vq->avail->ring[(res_base_idx) & (vq->size - 1)];
-
-		desc = &vq->desc[desc_idx];
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc = &vq->desc[desc->next];
-			buff_addr = gpa_to_vva(dev, desc->addr);
-			phys_addr = gpa_to_hpa(dev, desc->addr, desc->len,
-					&addr_type);
-		} else {
-			buff_addr = gpa_to_vva(dev,
-					desc->addr + vq->vhost_hlen);
-			phys_addr = gpa_to_hpa(dev,
-					desc->addr + vq->vhost_hlen,
-					desc->len, &addr_type);
-		}
-
-		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
-			RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Invalid frame buffer"
-				" address found when attaching RX frame buffer"
-				" address!\n", dev->device_fh);
-			put_desc_to_used_list_zcp(vq, desc_idx);
-			continue;
-		}
-
-		/*
-		 * Check if the frame buffer address from guest crosses
-		 * sub-region or not.
-		 */
-		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Frame buffer address cross "
-				"sub-regioin found when attaching RX frame "
-				"buffer address!\n",
-				dev->device_fh);
-			put_desc_to_used_list_zcp(vq, desc_idx);
-			continue;
-		}
-	} while (unlikely(phys_addr == 0));
-
-	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
-	if (unlikely(mbuf == NULL)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in attach_rxmbuf_zcp: "
-			"ring_sc_dequeue fail.\n",
-			dev->device_fh);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		return;
-	}
-
-	if (unlikely(vpool->buf_size > desc->len)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in attach_rxmbuf_zcp: frame buffer "
-			"length(%d) of descriptor idx: %d less than room "
-			"size required: %d\n",
-			dev->device_fh, desc->len, desc_idx, vpool->buf_size);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
-		return;
-	}
-
-	mbuf->buf_addr = (void *)(uintptr_t)(buff_addr - RTE_PKTMBUF_HEADROOM);
-	mbuf->pkt.data = (void *)(uintptr_t)(buff_addr);
-	mbuf->buf_physaddr = phys_addr - RTE_PKTMBUF_HEADROOM;
-	mbuf->pkt.data_len = desc->len;
-	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in attach_rxmbuf_zcp: res base idx:%d, "
-		"descriptor idx:%d\n",
-		dev->device_fh, res_base_idx, desc_idx);
-
-	__rte_mbuf_raw_free(mbuf);
-
-	return;
-}
-
-/*
- * Detach an attched packet mbuf -
- *  - restore original mbuf address and length values.
- *  - reset pktmbuf data and data_len to their default values.
- *  All other fields of the given packet mbuf will be left intact.
- *
- * @param m
- *   The attached packet mbuf.
- */
-static inline void pktmbuf_detach_zcp(struct rte_mbuf *m)
-{
-	const struct rte_mempool *mp = m->pool;
-	void *buf = RTE_MBUF_TO_BADDR(m);
-	uint32_t buf_ofs;
-	uint32_t buf_len = mp->elt_size - sizeof(*m);
-	m->buf_physaddr = rte_mempool_virt2phy(mp, m) + sizeof(*m);
-
-	m->buf_addr = buf;
-	m->buf_len = (uint16_t)buf_len;
-
-	buf_ofs = (RTE_PKTMBUF_HEADROOM <= m->buf_len) ?
-			RTE_PKTMBUF_HEADROOM : m->buf_len;
-	m->pkt.data = (char *) m->buf_addr + buf_ofs;
-
-	m->pkt.data_len = 0;
-}
-
-/*
- * This function is called after packets have been transimited. It fetchs mbuf
- * from vpool->pool, detached it and put into vpool->ring. It also update the
- * used index and kick the guest if necessary.
- */
-static inline uint32_t __attribute__((always_inline))
-txmbuf_clean_zcp(struct virtio_net *dev, struct vpool *vpool)
-{
-	struct rte_mbuf *mbuf;
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
-	uint32_t used_idx = vq->last_used_idx & (vq->size - 1);
-	uint32_t index = 0;
-	uint32_t mbuf_count = rte_mempool_count(vpool->pool);
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool before "
-		"clean is: %d\n",
-		dev->device_fh, mbuf_count);
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring before "
-		"clean  is : %d\n",
-		dev->device_fh, rte_ring_count(vpool->ring));
-
-	for (index = 0; index < mbuf_count; index++) {
-		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
-		if (likely(RTE_MBUF_INDIRECT(mbuf)))
-			pktmbuf_detach_zcp(mbuf);
-		rte_ring_sp_enqueue(vpool->ring, mbuf);
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = MBUF_HEADROOM_UINT32(mbuf);
-		vq->used->ring[used_idx].len = 0;
-
-		used_idx = (used_idx + 1) & (vq->size - 1);
-	}
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool after "
-		"clean is: %d\n",
-		dev->device_fh, rte_mempool_count(vpool->pool));
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring after "
-		"clean  is : %d\n",
-		dev->device_fh, rte_ring_count(vpool->ring));
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: before updated "
-		"vq->last_used_idx:%d\n",
-		dev->device_fh, vq->last_used_idx);
-
-	vq->last_used_idx += mbuf_count;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: after updated "
-		"vq->last_used_idx:%d\n",
-		dev->device_fh, vq->last_used_idx);
-
-	rte_compiler_barrier();
-
-	*(volatile uint16_t *)&vq->used->idx += mbuf_count;
-
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-	return 0;
-}
-
-/*
- * This function is called when a virtio device is destroy.
- * It fetchs mbuf from vpool->pool, and detached it, and put into vpool->ring.
- */
-static void mbuf_destroy_zcp(struct vpool *vpool)
-{
-	struct rte_mbuf *mbuf = NULL;
-	uint32_t index, mbuf_count = rte_mempool_count(vpool->pool);
-
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in mempool before "
-		"mbuf_destroy_zcp is: %d\n",
-		mbuf_count);
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in  ring before "
-		"mbuf_destroy_zcp  is : %d\n",
-		rte_ring_count(vpool->ring));
-
-	for (index = 0; index < mbuf_count; index++) {
-		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
-		if (likely(mbuf != NULL)) {
-			if (likely(RTE_MBUF_INDIRECT(mbuf)))
-				pktmbuf_detach_zcp(mbuf);
-			rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
-		}
-	}
-
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in mempool after "
-		"mbuf_destroy_zcp is: %d\n",
-		rte_mempool_count(vpool->pool));
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in ring after "
-		"mbuf_destroy_zcp is : %d\n",
-		rte_ring_count(vpool->ring));
-}
-
-/*
- * This function update the use flag and counter.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx_zcp(struct virtio_net *dev, struct rte_mbuf **pkts,
-	uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *buff;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr
-		= {{0, 0, 0, 0, 0, 0}, 0};
-	uint64_t buff_hdr_addr = 0;
-	uint32_t head[MAX_PKT_BURST], packet_len = 0;
-	uint32_t head_idx, packet_success = 0;
-	uint16_t res_cur_idx;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
-
-	if (count == 0)
-		return 0;
-
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
-
-	res_cur_idx = vq->last_used_idx;
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n",
-		dev->device_fh, res_cur_idx, res_cur_idx + count);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (head_idx = 0; head_idx < count; head_idx++)
-		head[head_idx] = MBUF_HEADROOM_UINT32(pkts[head_idx]);
-
-	/*Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-
-	while (packet_success != count) {
-		/* Get descriptor from available ring */
-		desc = &vq->desc[head[packet_success]];
-
-		buff = pkts[packet_success];
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in dev_rx_zcp: update the used idx for "
-			"pkt[%d] descriptor idx: %d\n",
-			dev->device_fh, packet_success,
-			MBUF_HEADROOM_UINT32(buff));
-
-		PRINT_PACKET(dev,
-			(uintptr_t)(((uint64_t)(uintptr_t)buff->buf_addr)
-			+ RTE_PKTMBUF_HEADROOM),
-			rte_pktmbuf_data_len(buff), 0);
-
-		/* Buffer address translation for virtio header. */
-		buff_hdr_addr = gpa_to_vva(dev, desc->addr);
-		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-		/*
-		 * If the descriptors are chained the header and data are
-		 * placed in separate buffers.
-		 */
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc->len = vq->vhost_hlen;
-			desc = &vq->desc[desc->next];
-			desc->len = rte_pktmbuf_data_len(buff);
-		} else {
-			desc->len = packet_len;
-		}
-
-		/* Update used ring with desc information */
-		vq->used->ring[res_cur_idx & (vq->size - 1)].id
-			= head[packet_success];
-		vq->used->ring[res_cur_idx & (vq->size - 1)].len
-			= packet_len;
-		res_cur_idx++;
-		packet_success++;
-
-		/* A header is required per buffer. */
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
-			(const void *)&virtio_hdr, vq->vhost_hlen);
-
-		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-
-		if (likely(packet_success < count)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success]]);
-		}
-	}
-
-	rte_compiler_barrier();
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in dev_rx_zcp: before update used idx: "
-		"vq.last_used_idx: %d, vq->used->idx: %d\n",
-		dev->device_fh, vq->last_used_idx, vq->used->idx);
-
-	*(volatile uint16_t *)&vq->used->idx += count;
-	vq->last_used_idx += count;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in dev_rx_zcp: after  update used idx: "
-		"vq.last_used_idx: %d, vq->used->idx: %d\n",
-		dev->device_fh, vq->last_used_idx, vq->used->idx);
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-	return count;
-}
-
-/*
- * This function routes the TX packet to the correct interface.
- * This may be a local device or the physical port.
- */
-static inline void __attribute__((always_inline))
-virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
-	uint32_t desc_idx, uint8_t need_copy)
-{
-	struct mbuf_table *tx_q;
-	struct rte_mbuf **m_table;
-	struct rte_mbuf *mbuf = NULL;
-	unsigned len, ret, offset = 0;
-	struct vpool *vpool;
-	struct virtio_net_data_ll *dev_ll = ll_root_used;
-	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
-	uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
-
-	/*Add packet to the port tx queue*/
-	tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-	len = tx_q->len;
-
-	/* Allocate an mbuf and populate the structure. */
-	vpool = &vpool_array[MAX_QUEUES + (uint16_t)dev->vmdq_rx_q];
-	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
-	if (unlikely(mbuf == NULL)) {
-		struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
-		RTE_LOG(ERR, VHOST_DATA,
-			"(%"PRIu64") Failed to allocate memory for mbuf.\n",
-			dev->device_fh);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		return;
-	}
-
-	if (vm2vm_mode == VM2VM_HARDWARE) {
-		/* Avoid using a vlan tag from any vm for external pkt, such as
-		 * vlan_tags[dev->device_fh], oterwise, it conflicts when pool
-		 * selection, MAC address determines it as an external pkt
-		 * which should go to network, while vlan tag determine it as
-		 * a vm2vm pkt should forward to another vm. Hardware confuse
-		 * such a ambiguous situation, so pkt will lost.
-		 */
-		vlan_tag = external_pkt_default_vlan_tag;
-		while (dev_ll != NULL) {
-			if (likely(dev_ll->dev->ready == DEVICE_RX) &&
-				ether_addr_cmp(&(pkt_hdr->d_addr),
-				&dev_ll->dev->mac_address)) {
-
-				/*
-				 * Drop the packet if the TX packet is destined
-				 * for the TX device.
-				 */
-				if (unlikely(dev_ll->dev->device_fh
-					== dev->device_fh)) {
-					LOG_DEBUG(VHOST_DATA,
-					"(%"PRIu64") TX: Source and destination"
-					"MAC addresses are the same. Dropping "
-					"packet.\n",
-					dev_ll->dev->device_fh);
-					MBUF_HEADROOM_UINT32(mbuf)
-						= (uint32_t)desc_idx;
-					__rte_mbuf_raw_free(mbuf);
-					return;
-				}
-
-				/*
-				 * Packet length offset 4 bytes for HW vlan
-				 * strip when L2 switch back.
-				 */
-				offset = 4;
-				vlan_tag =
-				(uint16_t)
-				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
-
-				LOG_DEBUG(VHOST_DATA,
-				"(%"PRIu64") TX: pkt to local VM device id:"
-				"(%"PRIu64") vlan tag: %d.\n",
-				dev->device_fh, dev_ll->dev->device_fh,
-				vlan_tag);
-
-				break;
-			}
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	mbuf->pkt.nb_segs = m->pkt.nb_segs;
-	mbuf->pkt.next = m->pkt.next;
-	mbuf->pkt.data_len = m->pkt.data_len + offset;
-	mbuf->pkt.pkt_len = mbuf->pkt.data_len;
-	if (unlikely(need_copy)) {
-		/* Copy the packet contents to the mbuf. */
-		rte_memcpy((void *)((uint8_t *)mbuf->pkt.data),
-			(const void *) ((uint8_t *)m->pkt.data),
-			m->pkt.data_len);
-	} else {
-		mbuf->pkt.data = m->pkt.data;
-		mbuf->buf_physaddr = m->buf_physaddr;
-		mbuf->buf_addr = m->buf_addr;
-	}
-	mbuf->ol_flags = PKT_TX_VLAN_PKT;
-	mbuf->pkt.vlan_macip.f.vlan_tci = vlan_tag;
-	mbuf->pkt.vlan_macip.f.l2_len = sizeof(struct ether_hdr);
-	mbuf->pkt.vlan_macip.f.l3_len = sizeof(struct ipv4_hdr);
-	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
-
-	tx_q->m_table[len] = mbuf;
-	len++;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in tx_route_zcp: pkt: nb_seg: %d, next:%s\n",
-		dev->device_fh,
-		mbuf->pkt.nb_segs,
-		(mbuf->pkt.next == NULL) ? "null" : "non-null");
-
-	if (enable_stats) {
-		dev_statistics[dev->device_fh].tx_total++;
-		dev_statistics[dev->device_fh].tx++;
-	}
-
-	if (unlikely(len == MAX_PKT_BURST)) {
-		m_table = (struct rte_mbuf **)tx_q->m_table;
-		ret = rte_eth_tx_burst(ports[0],
-			(uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
-
-		/*
-		 * Free any buffers not handled by TX and update
-		 * the port stats.
-		 */
-		if (unlikely(ret < len)) {
-			do {
-				rte_pktmbuf_free(m_table[ret]);
-			} while (++ret < len);
-		}
-
-		len = 0;
-		txmbuf_clean_zcp(dev, vpool);
-	}
-
-	tx_q->len = len;
-
-	return;
-}
-
-/*
- * This function TX all available packets in virtio TX queue for one
- * virtio-net device. If it is first packet, it learns MAC address and
- * setup VMDQ.
- */
-static inline void __attribute__((always_inline))
-virtio_dev_tx_zcp(struct virtio_net *dev)
-{
-	struct rte_mbuf m;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t buff_addr = 0, phys_addr;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t i;
-	uint16_t free_entries, packet_success = 0;
-	uint16_t avail_idx;
-	uint8_t need_copy = 0;
-	hpa_type addr_type;
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx_res == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx_res & (vq->size - 1)]);
-
-	/* Get the number of free entries in the ring */
-	free_entries = (avail_idx - vq->last_used_idx_res);
-
-	/* Limit to MAX_PKT_BURST. */
-	free_entries
-		= (free_entries > MAX_PKT_BURST) ? MAX_PKT_BURST : free_entries;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
-		dev->device_fh, free_entries);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i]
-			= vq->avail->ring[(vq->last_used_idx_res + i)
-			& (vq->size - 1)];
-
-	vq->last_used_idx_res += free_entries;
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (packet_success < free_entries) {
-		desc = &vq->desc[head[packet_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		phys_addr = gpa_to_hpa(dev, desc->addr, desc->len, &addr_type);
-
-		if (likely(packet_success < (free_entries - 1)))
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success + 1]]);
-
-		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Invalid frame buffer address found"
-				"when TX packets!\n",
-				dev->device_fh);
-			packet_success++;
-			continue;
-		}
-
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)buff_addr);
-
-		/*
-		 * Setup dummy mbuf. This is copied to a real mbuf if
-		 * transmitted out the physical port.
-		 */
-		m.pkt.data_len = desc->len;
-		m.pkt.nb_segs = 1;
-		m.pkt.next = NULL;
-		m.pkt.data = (void *)(uintptr_t)buff_addr;
-		m.buf_addr = m.pkt.data;
-		m.buf_physaddr = phys_addr;
-
-		/*
-		 * Check if the frame buffer address from guest crosses
-		 * sub-region or not.
-		 */
-		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Frame buffer address cross "
-				"sub-regioin found when attaching TX frame "
-				"buffer address!\n",
-				dev->device_fh);
-			need_copy = 1;
-		} else
-			need_copy = 0;
-
-		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
-
-		/*
-		 * If this is the first received packet we need to learn
-		 * the MAC and setup VMDQ
-		 */
-		if (unlikely(dev->ready == DEVICE_MAC_LEARNING)) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
-				/*
-				 * Discard frame if device is scheduled for
-				 * removal or a duplicate MAC address is found.
-				 */
-				packet_success += free_entries;
-				vq->last_used_idx += packet_success;
-				break;
-			}
-		}
-
-		virtio_tx_route_zcp(dev, &m, head[packet_success], need_copy);
-		packet_success++;
-	}
-}
-
-/*
- * This function is called by each data core. It handles all RX/TX registered
- * with the core. For TX the specific lcore linked list is used. For RX, MAC
- * addresses are compared with all devices in the main linked list.
- */
-static int
-switch_worker_zcp(__attribute__((unused)) void *arg)
-{
-	struct virtio_net *dev = NULL;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-	struct virtio_net_data_ll *dev_ll;
-	struct mbuf_table *tx_q;
-	volatile struct lcore_ll_info *lcore_ll;
-	const uint64_t drain_tsc
-		= (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S
-		* BURST_TX_DRAIN_US;
-	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
-	unsigned ret;
-	const uint16_t lcore_id = rte_lcore_id();
-	uint16_t count_in_ring, rx_count = 0;
-
-	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
-
-	lcore_ll = lcore_info[lcore_id].lcore_ll;
-	prev_tsc = 0;
-
-	while (1) {
-		cur_tsc = rte_rdtsc();
-
-		/* TX burst queue drain */
-		diff_tsc = cur_tsc - prev_tsc;
-		if (unlikely(diff_tsc > drain_tsc)) {
-			/*
-			 * Get mbuf from vpool.pool and detach mbuf and
-			 * put back into vpool.ring.
-			 */
-			dev_ll = lcore_ll->ll_root_used;
-			while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
-				/* Get virtio device ID */
-				dev = dev_ll->dev;
-
-				if (likely(!dev->remove)) {
-					tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-					if (tx_q->len) {
-						LOG_DEBUG(VHOST_DATA,
-						"TX queue drained after timeout"
-						" with burst size %u\n",
-						tx_q->len);
-
-						/*
-						 * Tx any packets in the queue
-						 */
-						ret = rte_eth_tx_burst(
-							ports[0],
-							(uint16_t)tx_q->txq_id,
-							(struct rte_mbuf **)
-							tx_q->m_table,
-							(uint16_t)tx_q->len);
-						if (unlikely(ret < tx_q->len)) {
-							do {
-								rte_pktmbuf_free(
-									tx_q->m_table[ret]);
-							} while (++ret < tx_q->len);
-						}
-						tx_q->len = 0;
-
-						txmbuf_clean_zcp(dev,
-							&vpool_array[MAX_QUEUES+dev->vmdq_rx_q]);
-					}
-				}
-				dev_ll = dev_ll->next;
-			}
-			prev_tsc = cur_tsc;
-		}
-
-		rte_prefetch0(lcore_ll->ll_root_used);
-
-		/*
-		 * Inform the configuration core that we have exited the linked
-		 * list and that no devices are in use if requested.
-		 */
-		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
-			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-
-		/* Process devices */
-		dev_ll = lcore_ll->ll_root_used;
-
-		while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
-			dev = dev_ll->dev;
-			if (unlikely(dev->remove)) {
-				dev_ll = dev_ll->next;
-				unlink_vmdq(dev);
-				dev->ready = DEVICE_SAFE_REMOVE;
-				continue;
-			}
-
-			if (likely(dev->ready == DEVICE_RX)) {
-				uint32_t index = dev->vmdq_rx_q;
-				uint16_t i;
-				count_in_ring
-				= rte_ring_count(vpool_array[index].ring);
-				uint16_t free_entries
-				= (uint16_t)get_available_ring_num_zcp(dev);
-
-				/*
-				 * Attach all mbufs in vpool.ring and put back
-				 * into vpool.pool.
-				 */
-				for (i = 0;
-				i < RTE_MIN(free_entries,
-				RTE_MIN(count_in_ring, MAX_PKT_BURST));
-				i++)
-					attach_rxmbuf_zcp(dev);
-
-				/* Handle guest RX */
-				rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst,
-					MAX_PKT_BURST);
-
-				if (rx_count) {
-					ret_count = virtio_dev_rx_zcp(dev,
-							pkts_burst, rx_count);
-					if (enable_stats) {
-						dev_statistics[dev->device_fh].rx_total
-							+= rx_count;
-						dev_statistics[dev->device_fh].rx
-							+= ret_count;
-					}
-					while (likely(rx_count)) {
-						rx_count--;
-						pktmbuf_detach_zcp(
-							pkts_burst[rx_count]);
-						rte_ring_sp_enqueue(
-							vpool_array[index].ring,
-							(void *)pkts_burst[rx_count]);
-					}
-				}
-			}
-
-			if (likely(!dev->remove))
-				/* Handle guest TX */
-				virtio_dev_tx_zcp(dev);
-
-			/* Move to the next device in the list */
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	return 0;
-}
-
-
-/*
- * Add an entry to a used linked list. A free entry must first be found
- * in the free linked list using get_data_ll_free_entry();
- */
-static void
-add_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev)
-{
-	struct virtio_net_data_ll *ll = *ll_root_addr;
-
-	/* Set next as NULL and use a compiler barrier to avoid reordering. */
-	ll_dev->next = NULL;
-	rte_compiler_barrier();
-
-	/* If ll == NULL then this is the first device. */
-	if (ll) {
-		/* Increment to the tail of the linked list. */
-		while ((ll->next != NULL) )
-			ll = ll->next;
-
-		ll->next = ll_dev;
-	} else {
-		*ll_root_addr = ll_dev;
-	}
-}
-
-/*
- * Remove an entry from a used linked list. The entry must then be added to
- * the free linked list using put_data_ll_free_entry().
- */
-static void
-rm_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev,
-	struct virtio_net_data_ll *ll_dev_last)
-{
-	struct virtio_net_data_ll *ll = *ll_root_addr;
-
-	if (unlikely((ll == NULL) || (ll_dev == NULL)))
-		return;
-
-	if (ll_dev == ll)
-		*ll_root_addr = ll_dev->next;
-	else
-		if (likely(ll_dev_last != NULL))
-			ll_dev_last->next = ll_dev->next;
-		else
-			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry form ll failed.\n");
-}
-
-/*
- * Find and return an entry from the free linked list.
- */
-static struct virtio_net_data_ll *
-get_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr)
-{
-	struct virtio_net_data_ll *ll_free = *ll_root_addr;
-	struct virtio_net_data_ll *ll_dev;
-
-	if (ll_free == NULL)
-		return NULL;
-
-	ll_dev = ll_free;
-	*ll_root_addr = ll_free->next;
-
-	return ll_dev;
-}
-
-/*
- * Place an entry back on to the free linked list.
- */
-static void
-put_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev)
-{
-	struct virtio_net_data_ll *ll_free = *ll_root_addr;
-
-	if (ll_dev == NULL)
-		return;
-
-	ll_dev->next = ll_free;
-	*ll_root_addr = ll_dev;
-}
-
-/*
- * Creates a linked list of a given size.
- */
-static struct virtio_net_data_ll *
-alloc_data_ll(uint32_t size)
-{
-	struct virtio_net_data_ll *ll_new;
-	uint32_t i;
-
-	/* Malloc and then chain the linked list. */
-	ll_new = malloc(size * sizeof(struct virtio_net_data_ll));
-	if (ll_new == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for ll_new.\n");
-		return NULL;
-	}
-
-	for (i = 0; i < size - 1; i++) {
-		ll_new[i].dev = NULL;
-		ll_new[i].next = &ll_new[i+1];
-	}
-	ll_new[i].next = NULL;
-
-	return (ll_new);
-}
-
-/*
- * Create the main linked list along with each individual cores linked list. A used and a free list
- * are created to manage entries.
- */
-static int
-init_data_ll (void)
-{
-	int lcore;
-
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		lcore_info[lcore].lcore_ll = malloc(sizeof(struct lcore_ll_info));
-		if (lcore_info[lcore].lcore_ll == NULL) {
-			RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for lcore_ll.\n");
-			return -1;
-		}
-
-		lcore_info[lcore].lcore_ll->device_num = 0;
-		lcore_info[lcore].lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-		lcore_info[lcore].lcore_ll->ll_root_used = NULL;
-		if (num_devices % num_switching_cores)
-			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll((num_devices / num_switching_cores) + 1);
-		else
-			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll(num_devices / num_switching_cores);
-	}
-
-	/* Allocate devices up to a maximum of MAX_DEVICES. */
-	ll_root_free = alloc_data_ll(MIN((num_devices), MAX_DEVICES));
-
-	return 0;
-}
-
-/*
- * Set virtqueue flags so that we do not receive interrupts.
- */
-static void
-set_irq_status (struct virtio_net *dev)
-{
-	dev->virtqueue[VIRTIO_RXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
-	dev->virtqueue[VIRTIO_TXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
-}
-
-/*
- * Remove a device from the specific data core linked list and from the main linked list. Synchonization
- * occurs through the use of the lcore dev_removal_flag. Device is made volatile here to avoid re-ordering
- * of dev->remove=1 which can cause an infinite loop in the rte_pause loop.
- */
-static void
-destroy_device (volatile struct virtio_net *dev)
-{
-	struct virtio_net_data_ll *ll_lcore_dev_cur;
-	struct virtio_net_data_ll *ll_main_dev_cur;
-	struct virtio_net_data_ll *ll_lcore_dev_last = NULL;
-	struct virtio_net_data_ll *ll_main_dev_last = NULL;
-	int lcore;
-
-	dev->flags &= ~VIRTIO_DEV_RUNNING;
-
-	/*set the remove flag. */
-	dev->remove = 1;
-
-	while(dev->ready != DEVICE_SAFE_REMOVE) {
-		rte_pause();
-	}
-
-	/* Search for entry to be removed from lcore ll */
-	ll_lcore_dev_cur = lcore_info[dev->coreid].lcore_ll->ll_root_used;
-	while (ll_lcore_dev_cur != NULL) {
-		if (ll_lcore_dev_cur->dev == dev) {
-			break;
-		} else {
-			ll_lcore_dev_last = ll_lcore_dev_cur;
-			ll_lcore_dev_cur = ll_lcore_dev_cur->next;
-		}
-	}
-
-	if (ll_lcore_dev_cur == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to find the dev to be destroy.\n",
-			dev->device_fh);
-		return;
-	}
-
-	/* Search for entry to be removed from main ll */
-	ll_main_dev_cur = ll_root_used;
-	ll_main_dev_last = NULL;
-	while (ll_main_dev_cur != NULL) {
-		if (ll_main_dev_cur->dev == dev) {
-			break;
-		} else {
-			ll_main_dev_last = ll_main_dev_cur;
-			ll_main_dev_cur = ll_main_dev_cur->next;
-		}
-	}
-
-	/* Remove entries from the lcore and main ll. */
-	rm_data_ll_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_used, ll_lcore_dev_cur, ll_lcore_dev_last);
-	rm_data_ll_entry(&ll_root_used, ll_main_dev_cur, ll_main_dev_last);
-
-	/* Set the dev_removal_flag on each lcore. */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		lcore_info[lcore].lcore_ll->dev_removal_flag = REQUEST_DEV_REMOVAL;
-	}
-
-	/*
-	 * Once each core has set the dev_removal_flag to ACK_DEV_REMOVAL we can be sure that
-	 * they can no longer access the device removed from the linked lists and that the devices
-	 * are no longer in use.
-	 */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		while (lcore_info[lcore].lcore_ll->dev_removal_flag != ACK_DEV_REMOVAL) {
-			rte_pause();
-		}
-	}
-
-	/* Add the entries back to the lcore and main free ll.*/
-	put_data_ll_free_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_free, ll_lcore_dev_cur);
-	put_data_ll_free_entry(&ll_root_free, ll_main_dev_cur);
-
-	/* Decrement number of device on the lcore. */
-	lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->device_num--;
-
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been removed from data core\n", dev->device_fh);
-
-	if (zero_copy) {
-		struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-		/* Stop the RX queue. */
-		if (rte_eth_dev_rx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In destroy_device: Failed to stop "
-				"rx queue:%d\n",
-				dev->device_fh,
-				dev->vmdq_rx_q);
-		}
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in destroy_device: Start put mbuf in "
-			"mempool back to ring for RX queue: %d\n",
-			dev->device_fh, dev->vmdq_rx_q);
-
-		mbuf_destroy_zcp(vpool);
-
-		/* Stop the TX queue. */
-		if (rte_eth_dev_tx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In destroy_device: Failed to "
-				"stop tx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-		}
-
-		vpool = &vpool_array[dev->vmdq_rx_q + MAX_QUEUES];
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") destroy_device: Start put mbuf in mempool "
-			"back to ring for TX queue: %d, dev:(%"PRIu64")\n",
-			dev->device_fh, (dev->vmdq_rx_q + MAX_QUEUES),
-			dev->device_fh);
-
-		mbuf_destroy_zcp(vpool);
-	}
-
-}
-
-/*
- * A new device is added to a data core. First the device is added to the main linked list
- * and the allocated to a specific data core.
- */
-static int
-new_device (struct virtio_net *dev)
-{
-	struct virtio_net_data_ll *ll_dev;
-	int lcore, core_add = 0;
-	uint32_t device_num_min = num_devices;
-
-	/* Add device to main ll */
-	ll_dev = get_data_ll_free_entry(&ll_root_free);
-	if (ll_dev == NULL) {
-		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") No free entry found in linked list. Device limit "
-			"of %d devices per core has been reached\n",
-			dev->device_fh, num_devices);
-		return -1;
-	}
-	ll_dev->dev = dev;
-	add_data_ll_entry(&ll_root_used, ll_dev);
-	ll_dev->dev->vmdq_rx_q
-		= ll_dev->dev->device_fh * (num_queues / num_devices);
-
-	if (zero_copy) {
-		uint32_t index = ll_dev->dev->vmdq_rx_q;
-		uint32_t count_in_ring, i;
-		struct mbuf_table *tx_q;
-
-		count_in_ring = rte_ring_count(vpool_array[index].ring);
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in new_device: mbuf count in mempool "
-			"before attach is: %d\n",
-			dev->device_fh,
-			rte_mempool_count(vpool_array[index].pool));
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in new_device: mbuf count in  ring "
-			"before attach  is : %d\n",
-			dev->device_fh, count_in_ring);
-
-		/*
-		 * Attach all mbufs in vpool.ring and put back intovpool.pool.
-		 */
-		for (i = 0; i < count_in_ring; i++)
-			attach_rxmbuf_zcp(dev);
-
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
-			"mempool after attach is: %d\n",
-			dev->device_fh,
-			rte_mempool_count(vpool_array[index].pool));
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
-			"ring after attach  is : %d\n",
-			dev->device_fh,
-			rte_ring_count(vpool_array[index].ring));
-
-		tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-		tx_q->txq_id = dev->vmdq_rx_q;
-
-		if (rte_eth_dev_tx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
-			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In new_device: Failed to start "
-				"tx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-
-			mbuf_destroy_zcp(vpool);
-			return -1;
-		}
-
-		if (rte_eth_dev_rx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
-			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In new_device: Failed to start "
-				"rx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-
-			/* Stop the TX queue. */
-			if (rte_eth_dev_tx_queue_stop(ports[0],
-				dev->vmdq_rx_q) != 0) {
-				LOG_DEBUG(VHOST_CONFIG,
-					"(%"PRIu64") In new_device: Failed to "
-					"stop tx queue:%d\n",
-					dev->device_fh, dev->vmdq_rx_q);
-			}
-
-			mbuf_destroy_zcp(vpool);
-			return -1;
-		}
-
-	}
-
-	/*reset ready flag*/
-	dev->ready = DEVICE_MAC_LEARNING;
-	dev->remove = 0;
-
-	/* Find a suitable lcore to add the device. */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		if (lcore_info[lcore].lcore_ll->device_num < device_num_min) {
-			device_num_min = lcore_info[lcore].lcore_ll->device_num;
-			core_add = lcore;
-		}
-	}
-	/* Add device to lcore ll */
-	ll_dev->dev->coreid = core_add;
-	ll_dev = get_data_ll_free_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_free);
-	if (ll_dev == NULL) {
-		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
-		dev->ready = DEVICE_SAFE_REMOVE;
-		destroy_device(dev);
-		return -1;
-	}
-	ll_dev->dev = dev;
-	add_data_ll_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_used, ll_dev);
-
-	/* Initialize device stats */
-	memset(&dev_statistics[dev->device_fh], 0, sizeof(struct device_statistics));
-
-	/* Disable notifications. */
-	set_irq_status(dev);
-	lcore_info[ll_dev->dev->coreid].lcore_ll->device_num++;
-	dev->flags |= VIRTIO_DEV_RUNNING;
-
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, dev->coreid);
-
-	return 0;
-}
-
-/*
- * These callback allow devices to be added to the data core when configuration
- * has been fully complete.
- */
-static const struct virtio_net_device_ops virtio_net_device_ops =
-{
-	.new_device =  new_device,
-	.destroy_device = destroy_device,
-};
-
-/*
- * This is a thread will wake up after a period to print stats if the user has
- * enabled them.
- */
-static void
-print_stats(void)
-{
-	struct virtio_net_data_ll *dev_ll;
-	uint64_t tx_dropped, rx_dropped;
-	uint64_t tx, tx_total, rx, rx_total;
-	uint32_t device_fh;
-	const char clr[] = { 27, '[', '2', 'J', '\0' };
-	const char top_left[] = { 27, '[', '1', ';', '1', 'H','\0' };
-
-	while(1) {
-		sleep(enable_stats);
-
-		/* Clear screen and move to top left */
-		printf("%s%s", clr, top_left);
-
-		printf("\nDevice statistics ====================================");
-
-		dev_ll = ll_root_used;
-		while (dev_ll != NULL) {
-			device_fh = (uint32_t)dev_ll->dev->device_fh;
-			tx_total = dev_statistics[device_fh].tx_total;
-			tx = dev_statistics[device_fh].tx;
-			tx_dropped = tx_total - tx;
-			if (zero_copy == 0) {
-				rx_total = rte_atomic64_read(
-					&dev_statistics[device_fh].rx_total_atomic);
-				rx = rte_atomic64_read(
-					&dev_statistics[device_fh].rx_atomic);
-			} else {
-				rx_total = dev_statistics[device_fh].rx_total;
-				rx = dev_statistics[device_fh].rx;
-			}
-			rx_dropped = rx_total - rx;
-
-			printf("\nStatistics for device %"PRIu32" ------------------------------"
-					"\nTX total: 		%"PRIu64""
-					"\nTX dropped: 		%"PRIu64""
-					"\nTX successful: 		%"PRIu64""
-					"\nRX total: 		%"PRIu64""
-					"\nRX dropped: 		%"PRIu64""
-					"\nRX successful: 		%"PRIu64"",
-					device_fh,
-					tx_total,
-					tx_dropped,
-					tx,
-					rx_total,
-					rx_dropped,
-					rx);
-
-			dev_ll = dev_ll->next;
-		}
-		printf("\n======================================================\n");
-	}
-}
-
-static void
-setup_mempool_tbl(int socket, uint32_t index, char *pool_name,
-	char *ring_name, uint32_t nb_mbuf)
-{
-	uint16_t roomsize = VIRTIO_DESCRIPTOR_LEN_ZCP + RTE_PKTMBUF_HEADROOM;
-	vpool_array[index].pool
-		= rte_mempool_create(pool_name, nb_mbuf, MBUF_SIZE_ZCP,
-		MBUF_CACHE_SIZE_ZCP, sizeof(struct rte_pktmbuf_pool_private),
-		rte_pktmbuf_pool_init, (void *)(uintptr_t)roomsize,
-		rte_pktmbuf_init, NULL, socket, 0);
-	if (vpool_array[index].pool != NULL) {
-		vpool_array[index].ring
-			= rte_ring_create(ring_name,
-				rte_align32pow2(nb_mbuf + 1),
-				socket, RING_F_SP_ENQ | RING_F_SC_DEQ);
-		if (likely(vpool_array[index].ring != NULL)) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"in setup_mempool_tbl: mbuf count in "
-				"mempool is: %d\n",
-				rte_mempool_count(vpool_array[index].pool));
-			LOG_DEBUG(VHOST_CONFIG,
-				"in setup_mempool_tbl: mbuf count in "
-				"ring   is: %d\n",
-				rte_ring_count(vpool_array[index].ring));
-		} else {
-			rte_exit(EXIT_FAILURE, "ring_create(%s) failed",
-				ring_name);
-		}
-
-		/* Need consider head room. */
-		vpool_array[index].buf_size = roomsize - RTE_PKTMBUF_HEADROOM;
-	} else {
-		rte_exit(EXIT_FAILURE, "mempool_create(%s) failed", pool_name);
-	}
-}
-
-
-/*
- * Main function, does initialisation and calls the per-lcore functions. The CUSE
- * device is also registered here to handle the IOCTLs.
- */
-int
-MAIN(int argc, char *argv[])
-{
-	struct rte_mempool *mbuf_pool = NULL;
-	unsigned lcore_id, core_id = 0;
-	unsigned nb_ports, valid_num_ports;
-	int ret;
-	uint8_t portid, queue_id = 0;
-	static pthread_t tid;
-
-	/* init EAL */
-	ret = rte_eal_init(argc, argv);
-	if (ret < 0)
-		rte_exit(EXIT_FAILURE, "Error with EAL initialization\n");
-	argc -= ret;
-	argv += ret;
-
-	/* parse app arguments */
-	ret = us_vhost_parse_args(argc, argv);
-	if (ret < 0)
-		rte_exit(EXIT_FAILURE, "Invalid argument\n");
-
-	if (rte_eal_pci_probe() != 0)
-		rte_exit(EXIT_FAILURE, "Error with NIC driver initialization\n");
-
-	for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id ++)
-		if (rte_lcore_is_enabled(lcore_id))
-			lcore_ids[core_id ++] = lcore_id;
-
-	if (rte_lcore_count() > RTE_MAX_LCORE)
-		rte_exit(EXIT_FAILURE,"Not enough cores\n");
-
-	/*set the number of swithcing cores available*/
-	num_switching_cores = rte_lcore_count()-1;
-
-	/* Get the number of physical ports. */
-	nb_ports = rte_eth_dev_count();
-	if (nb_ports > RTE_MAX_ETHPORTS)
-		nb_ports = RTE_MAX_ETHPORTS;
-
-	/*
-	 * Update the global var NUM_PORTS and global array PORTS
-	 * and get value of var VALID_NUM_PORTS according to system ports number
-	 */
-	valid_num_ports = check_ports_num(nb_ports);
-
-	if ((valid_num_ports ==  0) || (valid_num_ports > MAX_SUP_PORTS)) {
-		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
-			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
-		return -1;
-	}
-
-	if (zero_copy == 0) {
-		/* Create the mbuf pool. */
-		mbuf_pool = rte_mempool_create(
-				"MBUF_POOL",
-				NUM_MBUFS_PER_PORT
-				* valid_num_ports,
-				MBUF_SIZE, MBUF_CACHE_SIZE,
-				sizeof(struct rte_pktmbuf_pool_private),
-				rte_pktmbuf_pool_init, NULL,
-				rte_pktmbuf_init, NULL,
-				rte_socket_id(), 0);
-		if (mbuf_pool == NULL)
-			rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
-
-		for (queue_id = 0; queue_id < MAX_QUEUES + 1; queue_id++)
-			vpool_array[queue_id].pool = mbuf_pool;
-
-		if (vm2vm_mode == VM2VM_HARDWARE) {
-			/* Enable VT loop back to let L2 switch to do it. */
-			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
-			LOG_DEBUG(VHOST_CONFIG,
-				"Enable loop back for L2 switch in vmdq.\n");
-		}
-	} else {
-		uint32_t nb_mbuf;
-		char pool_name[RTE_MEMPOOL_NAMESIZE];
-		char ring_name[RTE_MEMPOOL_NAMESIZE];
-
-		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
-		rx_conf_default.rx_drop_en = 0;
-		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
-		nb_mbuf = num_rx_descriptor
-			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
-			+ num_switching_cores * MAX_PKT_BURST;
-
-		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
-			snprintf(pool_name, sizeof(pool_name),
-				"rxmbuf_pool_%u", queue_id);
-			snprintf(ring_name, sizeof(ring_name),
-				"rxmbuf_ring_%u", queue_id);
-			setup_mempool_tbl(rte_socket_id(), queue_id,
-				pool_name, ring_name, nb_mbuf);
-		}
-
-		nb_mbuf = num_tx_descriptor
-				+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
-				+ num_switching_cores * MAX_PKT_BURST;
-
-		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
-			snprintf(pool_name, sizeof(pool_name),
-				"txmbuf_pool_%u", queue_id);
-			snprintf(ring_name, sizeof(ring_name),
-				"txmbuf_ring_%u", queue_id);
-			setup_mempool_tbl(rte_socket_id(),
-				(queue_id + MAX_QUEUES),
-				pool_name, ring_name, nb_mbuf);
-		}
-
-		if (vm2vm_mode == VM2VM_HARDWARE) {
-			/* Enable VT loop back to let L2 switch to do it. */
-			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
-			LOG_DEBUG(VHOST_CONFIG,
-				"Enable loop back for L2 switch in vmdq.\n");
-		}
-	}
-	/* Set log level. */
-	rte_set_log_level(LOG_LEVEL);
-
-	/* initialize all ports */
-	for (portid = 0; portid < nb_ports; portid++) {
-		/* skip ports that are not enabled */
-		if ((enabled_port_mask & (1 << portid)) == 0) {
-			RTE_LOG(INFO, VHOST_PORT,
-				"Skipping disabled port %d\n", portid);
-			continue;
-		}
-		if (port_init(portid) != 0)
-			rte_exit(EXIT_FAILURE,
-				"Cannot initialize network ports\n");
-	}
-
-	/* Initialise all linked lists. */
-	if (init_data_ll() == -1)
-		rte_exit(EXIT_FAILURE, "Failed to initialize linked list\n");
-
-	/* Initialize device stats */
-	memset(&dev_statistics, 0, sizeof(dev_statistics));
-
-	/* Enable stats if the user option is set. */
-	if (enable_stats)
-		pthread_create(&tid, NULL, (void*)print_stats, NULL );
-
-	/* Launch all data cores. */
-	if (zero_copy == 0) {
-		RTE_LCORE_FOREACH_SLAVE(lcore_id) {
-			rte_eal_remote_launch(switch_worker,
-				mbuf_pool, lcore_id);
-		}
-	} else {
-		uint32_t count_in_mempool, index, i;
-		for (index = 0; index < 2*MAX_QUEUES; index++) {
-			/* For all RX and TX queues. */
-			count_in_mempool
-				= rte_mempool_count(vpool_array[index].pool);
-
-			/*
-			 * Transfer all un-attached mbufs from vpool.pool
-			 * to vpoo.ring.
-			 */
-			for (i = 0; i < count_in_mempool; i++) {
-				struct rte_mbuf *mbuf
-					= __rte_mbuf_raw_alloc(
-						vpool_array[index].pool);
-				rte_ring_sp_enqueue(vpool_array[index].ring,
-						(void *)mbuf);
-			}
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"in MAIN: mbuf count in mempool at initial "
-				"is: %d\n", count_in_mempool);
-			LOG_DEBUG(VHOST_CONFIG,
-				"in MAIN: mbuf count in  ring at initial  is :"
-				" %d\n",
-				rte_ring_count(vpool_array[index].ring));
-		}
-
-		RTE_LCORE_FOREACH_SLAVE(lcore_id)
-			rte_eal_remote_launch(switch_worker_zcp, NULL,
-				lcore_id);
-	}
-
-	/* Register CUSE device to handle IOCTLs. */
-	ret = register_cuse_device((char*)&dev_basename, dev_index, get_virtio_net_callbacks());
-	if (ret != 0)
-		rte_exit(EXIT_FAILURE,"CUSE device setup failure.\n");
-
-	init_virtio_net(&virtio_net_device_ops);
-
-	/* Start CUSE session. */
-	start_cuse_session_loop();
-	return 0;
-
-}
-
diff --git a/examples/vhost/main.h b/examples/vhost/main.h
deleted file mode 100644
index c15d938..0000000
--- a/examples/vhost/main.h
+++ /dev/null
@@ -1,86 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _MAIN_H_
-#define _MAIN_H_
-
-#ifdef RTE_EXEC_ENV_BAREMETAL
-#define MAIN _main
-#else
-#define MAIN main
-#endif
-
-//#define DEBUG
-
-#ifdef DEBUG
-#define LOG_LEVEL RTE_LOG_DEBUG
-#define LOG_DEBUG(log_type, fmt, args...) do {	\
-	RTE_LOG(DEBUG, log_type, fmt, ##args);		\
-} while (0)
-#else
-#define LOG_LEVEL RTE_LOG_INFO
-#define LOG_DEBUG(log_type, fmt, args...) do{} while(0)
-#endif
-
-/* Macros for printing using RTE_LOG */
-#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
-#define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER2
-#define RTE_LOGTYPE_VHOST_PORT   RTE_LOGTYPE_USER3
-
-/*
- * Device linked list structure for data path.
- */
-struct virtio_net_data_ll
-{
-	struct virtio_net			*dev;	/* Pointer to device created by configuration core. */
-	struct virtio_net_data_ll	*next;  /* Pointer to next device in linked list. */
-};
-
-/*
- * Structure containing data core specific information.
- */
-struct lcore_ll_info
-{
-	struct virtio_net_data_ll	*ll_root_free; 		/* Pointer to head in free linked list. */
-	struct virtio_net_data_ll	*ll_root_used;		/* Pointer to head of used linked list. */
-	uint32_t 					device_num;			/* Number of devices on lcore. */
-	volatile uint8_t			dev_removal_flag;	/* Flag to synchronize device removal. */
-};
-
-struct lcore_info
-{
-	struct lcore_ll_info	*lcore_ll;	/* Pointer to data core specific lcore_ll_info struct */
-};
-
-int MAIN(int argc, char **argv);
-#endif /* _MAIN_H_ */
diff --git a/examples/vhost/vhost-net-cdev.c b/examples/vhost/vhost-net-cdev.c
deleted file mode 100644
index 8cf806a..0000000
--- a/examples/vhost/vhost-net-cdev.c
+++ /dev/null
@@ -1,367 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <errno.h>
-#include <fuse/cuse_lowlevel.h>
-#include <linux/limits.h>
-#include <linux/vhost.h>
-#include <stdint.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <rte_ethdev.h>
-#include <rte_log.h>
-#include <rte_string_fns.h>
-
-#include "main.h"
-#include "vhost-net-cdev.h"
-
-#define FUSE_OPT_DUMMY 		"\0\0"
-#define FUSE_OPT_FORE 		"-f\0\0"
-#define FUSE_OPT_NOMULTI 	"-s\0\0"
-
-const uint32_t	default_major = 231;
-const uint32_t	default_minor = 1;
-const char		cuse_device_name[]	= "/dev/cuse";
-const char		default_cdev[] = "vhost-net";
-
-static struct fuse_session			*session;
-static struct vhost_net_device_ops	const *ops;
-
-/*
- * Returns vhost_device_ctx from given fuse_req_t. The index is populated later when
- * the device is added to the device linked list.
- */
-static struct vhost_device_ctx
-fuse_req_to_vhost_ctx(fuse_req_t req, struct fuse_file_info *fi)
-{
-	struct vhost_device_ctx ctx;
-	struct fuse_ctx const *const req_ctx = fuse_req_ctx(req);
-
-	ctx.pid = req_ctx->pid;
-	ctx.fh = fi->fh;
-
-	return ctx;
-}
-
-/*
- * When the device is created in QEMU it gets initialised here and added to the device linked list.
- */
-static void
-vhost_net_open(fuse_req_t req, struct fuse_file_info *fi)
-{
-	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
-	int err = 0;
-
-	err = ops->new_device(ctx);
-	if (err == -1) {
-		fuse_reply_err(req, EPERM);
-		return;
-	}
-
-	fi->fh = err;
-
-	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device configuration started\n", fi->fh);
-	fuse_reply_open(req, fi);
-}
-
-/*
- * When QEMU is shutdown or killed the device gets released.
- */
-static void
-vhost_net_release(fuse_req_t req, struct fuse_file_info *fi)
-{
-	int err = 0;
-	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
-
-	ops->destroy_device(ctx);
-	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device released\n", ctx.fh);
-	fuse_reply_err(req, err);
-}
-
-/*
- * Boilerplate code for CUSE IOCTL
- * Implicit arguments: ctx, req, result.
- */
-#define VHOST_IOCTL(func) do {								\
-	result = (func)(ctx);									\
-	fuse_reply_ioctl(req, result, NULL, 0);					\
-} while(0)													\
-
-/*
- * Boilerplate IOCTL RETRY
- * Implicit arguments: req.
- */
-#define VHOST_IOCTL_RETRY(size_r, size_w) do {									\
-	struct iovec iov_r = { arg, (size_r) };										\
-	struct iovec iov_w = { arg, (size_w) };										\
-	fuse_reply_ioctl_retry(req, &iov_r, (size_r)?1:0, &iov_w, (size_w)?1:0);	\
-} while(0)																		\
-
-/*
- * Boilerplate code for CUSE Read IOCTL
- * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
- */
-#define VHOST_IOCTL_R(type, var, func) do {				\
-	if (!in_bufsz) {									\
-		VHOST_IOCTL_RETRY(sizeof(type), 0);				\
-	} else {											\
-		(var) = *(const type * ) in_buf;				\
-		result = func(ctx, &(var));						\
-		fuse_reply_ioctl(req, result, NULL, 0);			\
-	}													\
-} while(0)												\
-
-/*
- *	Boilerplate code for CUSE Write IOCTL
- * Implicit arguments: ctx, req, result, out_bufsz.
- */
-#define	VHOST_IOCTL_W(type, var, func) do {						\
-	if (!out_bufsz) {											\
-		VHOST_IOCTL_RETRY(0, sizeof(type));						\
-	} else {													\
-		result = (func)(ctx, &(var));							\
-		fuse_reply_ioctl(req, result, &(var), sizeof(type));	\
-	}															\
-} while(0)														\
-
-/*
- * Boilerplate code for CUSE Read/Write IOCTL
- * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
- */
-#define VHOST_IOCTL_RW(type1, var1, type2, var2, func) do {			\
-	if (!in_bufsz) {												\
-		VHOST_IOCTL_RETRY(sizeof(type1), sizeof(type2));			\
-	} else {														\
-		(var1) = *(const type1* ) (in_buf);							\
-		result = (func)(ctx, (var1), &(var2));						\
-		fuse_reply_ioctl(req, result, &(var2), sizeof(type2));		\
-	}																\
-} while(0)															\
-
-/*
- * The IOCTLs are handled using CUSE/FUSE in userspace. Depending on
- * the type of IOCTL a buffer is requested to read or to write. This
- * request is handled by FUSE and the buffer is then given to CUSE.
- */
-static void
-vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
-		struct fuse_file_info *fi, __rte_unused unsigned flags,
-		const void *in_buf, size_t in_bufsz, size_t out_bufsz)
-{
-	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
-	struct vhost_vring_file file;
-	struct vhost_vring_state state;
-	struct vhost_vring_addr addr;
-	uint64_t features;
-	uint32_t index;
-	int result = 0;
-
-	switch(cmd)
-	{
-		case VHOST_NET_SET_BACKEND:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_NET_SET_BACKEND\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_backend);
-			break;
-
-		case VHOST_GET_FEATURES:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_FEATURES\n", ctx.fh);
-			VHOST_IOCTL_W(uint64_t, features, ops->get_features);
-			break;
-
-		case VHOST_SET_FEATURES:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_FEATURES\n", ctx.fh);
-			VHOST_IOCTL_R(uint64_t, features, ops->set_features);
-			break;
-
-		case VHOST_RESET_OWNER:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_RESET_OWNER\n", ctx.fh);
-			VHOST_IOCTL(ops->reset_owner);
-			break;
-
-		case VHOST_SET_OWNER:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_OWNER\n", ctx.fh);
-			VHOST_IOCTL(ops->set_owner);
-			break;
-
-		case VHOST_SET_MEM_TABLE:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_MEM_TABLE\n", ctx.fh);
-			static struct vhost_memory mem_temp;
-
-			switch(in_bufsz){
-				case 0:
-					VHOST_IOCTL_RETRY(sizeof(struct vhost_memory), 0);
-					break;
-
-				case sizeof(struct vhost_memory):
-					mem_temp = *(const struct vhost_memory *) in_buf;
-
-					if (mem_temp.nregions > 0) {
-						VHOST_IOCTL_RETRY(sizeof(struct vhost_memory) + (sizeof(struct vhost_memory_region) * mem_temp.nregions), 0);
-					} else {
-						result = -1;
-						fuse_reply_ioctl(req, result, NULL, 0);
-					}
-					break;
-
-				default:
-					result = ops->set_mem_table(ctx, in_buf, mem_temp.nregions);
-					if (result)
-						fuse_reply_err(req, EINVAL);
-					else
-						fuse_reply_ioctl(req, result, NULL, 0);
-
-			}
-
-			break;
-
-		case VHOST_SET_VRING_NUM:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_NUM\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_num);
-			break;
-
-		case VHOST_SET_VRING_BASE:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_BASE\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_base);
-			break;
-
-		case VHOST_GET_VRING_BASE:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_VRING_BASE\n", ctx.fh);
-			VHOST_IOCTL_RW(uint32_t, index, struct vhost_vring_state, state, ops->get_vring_base);
-			break;
-
-		case VHOST_SET_VRING_ADDR:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_ADDR\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_addr, addr, ops->set_vring_addr);
-			break;
-
-		case VHOST_SET_VRING_KICK:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_KICK\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_kick);
-			break;
-
-		case VHOST_SET_VRING_CALL:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_CALL\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_call);
-			break;
-
-		default:
-			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") IOCTL: DOESN NOT EXIST\n", ctx.fh);
-			result = -1;
-			fuse_reply_ioctl(req, result, NULL, 0);
-	}
-
-	if (result < 0) {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: FAIL\n", ctx.fh);
-	} else {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: SUCCESS\n", ctx.fh);
-	}
-}
-
-/*
- * Structure handling open, release and ioctl function pointers is populated.
- */
-static const struct cuse_lowlevel_ops vhost_net_ops = {
-	.open		= vhost_net_open,
-	.release	= vhost_net_release,
-	.ioctl		= vhost_net_ioctl,
-};
-
-/*
- * cuse_info is populated and used to register the cuse device. vhost_net_device_ops are
- * also passed when the device is registered in main.c.
- */
-int
-register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const pops)
-{
-	struct cuse_info cuse_info;
-	char device_name[PATH_MAX] = "";
-	char char_device_name[PATH_MAX] = "";
-	const char *device_argv[] = { device_name };
-
-	char fuse_opt_dummy[] = FUSE_OPT_DUMMY;
-	char fuse_opt_fore[] = FUSE_OPT_FORE;
-	char fuse_opt_nomulti[] = FUSE_OPT_NOMULTI;
-	char *fuse_argv[] = {fuse_opt_dummy, fuse_opt_fore, fuse_opt_nomulti};
-
-	if (access(cuse_device_name, R_OK | W_OK) < 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s can't be accessed, maybe not exist\n", cuse_device_name);
-		return -1;
-	}
-
-	/*
-	 * The device name is created. This is passed to QEMU so that it can register
-	 * the device with our application. The index allows us to have multiple instances
-	 * of userspace vhost which we can then add devices to separately.
-	 */
-	if (strncmp(base_name, default_cdev, PATH_MAX)!=0) {
-		snprintf(device_name, PATH_MAX, "DEVNAME=%s-%d", base_name, index);
-		snprintf(char_device_name, PATH_MAX, "/dev/%s-%d", base_name, index);
-	} else {
-		snprintf(device_name, PATH_MAX, "DEVNAME=%s", base_name);
-		snprintf(char_device_name, PATH_MAX, "/dev/%s", base_name);
-	}
-
-	/* Check if device already exists. */
-	if (access(char_device_name, F_OK) != -1) {
-		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s already exists\n", char_device_name);
-		return -1;
-	}
-
-	memset(&cuse_info, 0, sizeof(cuse_info));
-	cuse_info.dev_major = default_major;
-	cuse_info.dev_minor = default_minor + index;
-	cuse_info.dev_info_argc = 1;
-	cuse_info.dev_info_argv = device_argv;
-	cuse_info.flags = CUSE_UNRESTRICTED_IOCTL;
-
-	ops = pops;
-
-	session = cuse_lowlevel_setup(3, fuse_argv,
-				&cuse_info, &vhost_net_ops, 0, NULL);
-	if (session == NULL)
-		return -1;
-
-	return 0;
-}
-
-/*
- * The CUSE session is launched allowing the application to receive open, release and ioctl calls.
- */
-int
-start_cuse_session_loop(void)
-{
-	fuse_session_loop(session);
-
-	return 0;
-}
diff --git a/examples/vhost/vhost-net-cdev.h b/examples/vhost/vhost-net-cdev.h
deleted file mode 100644
index 575daa9..0000000
--- a/examples/vhost/vhost-net-cdev.h
+++ /dev/null
@@ -1,83 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _VHOST_NET_CDEV_H_
-#define _VHOST_NET_CDEV_H_
-
-#include <linux/vhost.h>
-
-struct vhost_memory;
-struct vhost_vring_state;
-struct vhost_vring_addr;
-struct vhost_vring_file;
-
-/*
- * Structure used to identify device context.
- */
-struct vhost_device_ctx
-{
-	pid_t		pid;	/* PID of process calling the IOCTL. */
-	uint64_t 	fh;		/* Populated with fi->fh to track the device index. */
-};
-
-/*
- * Structure contains function pointers to be defined in virtio-net.c. These
- * functions are called in CUSE context and are used to configure devices.
- */
-struct vhost_net_device_ops {
-	int (* new_device) 		(struct vhost_device_ctx);
-	void (* destroy_device) (struct vhost_device_ctx);
-
-	int (* get_features) 	(struct vhost_device_ctx, uint64_t *);
-	int (* set_features) 	(struct vhost_device_ctx, uint64_t *);
-
-	int (* set_mem_table) 	(struct vhost_device_ctx, const void *, uint32_t);
-
-	int (* set_vring_num) 	(struct vhost_device_ctx, struct vhost_vring_state *);
-	int (* set_vring_addr) 	(struct vhost_device_ctx, struct vhost_vring_addr *);
-	int (* set_vring_base) 	(struct vhost_device_ctx, struct vhost_vring_state *);
-	int (* get_vring_base) 	(struct vhost_device_ctx, uint32_t, struct vhost_vring_state *);
-
-	int (* set_vring_kick) 	(struct vhost_device_ctx, struct vhost_vring_file *);
-	int (* set_vring_call) 	(struct vhost_device_ctx, struct vhost_vring_file *);
-
-	int (* set_backend) 	(struct vhost_device_ctx, struct vhost_vring_file *);
-
-	int (* set_owner) 		(struct vhost_device_ctx);
-	int (* reset_owner) 	(struct vhost_device_ctx);
-};
-
-int register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const);
-int start_cuse_session_loop(void);
-
-#endif /* _VHOST_NET_CDEV_H_ */
diff --git a/examples/vhost/virtio-net.c b/examples/vhost/virtio-net.c
deleted file mode 100644
index 5e659c7..0000000
--- a/examples/vhost/virtio-net.c
+++ /dev/null
@@ -1,1165 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <dirent.h>
-#include <fuse/cuse_lowlevel.h>
-#include <linux/vhost.h>
-#include <linux/virtio_net.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <sys/eventfd.h>
-#include <sys/ioctl.h>
-#include <sys/mman.h>
-#include <unistd.h>
-
-#include <rte_ethdev.h>
-#include <rte_log.h>
-#include <rte_string_fns.h>
-#include <rte_memory.h>
-
-#include "main.h"
-#include "virtio-net.h"
-#include "vhost-net-cdev.h"
-#include "eventfd_link/eventfd_link.h"
-
-const char eventfd_cdev[] = "/dev/eventfd-link";
-
-extern uint32_t num_devices;
-static uint32_t num_cur_devices = 0;
-
-/* device ops to add/remove device to data core. */
-static struct virtio_net_device_ops const * notify_ops;
-/* Root address of the linked list in the configuration core. */
-static struct virtio_net_config_ll			*ll_root = NULL;
-
-/* Features supported by this application. RX merge buffers are disabled by default. */
-uint64_t VHOST_FEATURES = (0ULL << VIRTIO_NET_F_MRG_RXBUF);
-
-/* Line size for reading maps file. */
-const uint32_t BUFSIZE = PATH_MAX;
-
-/* Size of prot char array in procmap. */
-#define PROT_SZ 5
-
-/* Number of elements in procmap struct. */
-#define PROCMAP_SZ 8
-
-/* Structure containing information gathered from maps file. */
-struct procmap
-{
-	uint64_t	va_start;			/* Start virtual address in file. */
-	uint64_t	len;				/* Size of file. */
-	uint64_t	pgoff;				/* Not used. */
-	uint32_t	maj;				/* Not used. */
-	uint32_t	min;				/* Not used. */
-	uint32_t	ino;				/* Not used. */
-	char		prot[PROT_SZ];		/* Not used. */
-	char		fname[PATH_MAX];	/* File name. */
-};
-
-/*
- * Converts QEMU virtual address to Vhost virtual address. This function is used
- * to convert the ring addresses to our address space.
- */
-static uint64_t
-qva_to_vva(struct virtio_net *dev, uint64_t qemu_va)
-{
-	struct virtio_memory_regions *region;
-	uint64_t vhost_va = 0;
-	uint32_t regionidx = 0;
-
-	/* Find the region where the address lives. */
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		region = &dev->mem->regions[regionidx];
-		if ((qemu_va >= region->userspace_address) &&
-				(qemu_va <= region->userspace_address +
-			 	region->memory_size)) {
-			vhost_va = dev->mem->mapped_address + qemu_va - dev->mem->base_address;
-			break;
-		}
-	}
-	return vhost_va;
-}
-
-/*
- * Locate the file containing QEMU's memory space and map it to our address space.
- */
-static int
-host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, uint64_t addr)
-{
-	struct dirent *dptr = NULL;
-	struct procmap procmap;
-	DIR *dp = NULL;
-	int fd;
-	int i;
-	char memfile[PATH_MAX];
-	char mapfile[PATH_MAX];
-	char procdir[PATH_MAX];
-	char resolved_path[PATH_MAX];
-	FILE		*fmap;
-	void		*map;
-	uint8_t 	found = 0;
-	char 		line[BUFSIZE];
-	char dlm[] = "-   :   ";
-	char *str, *sp, *in[PROCMAP_SZ];
-	char *end = NULL;
-
-	/* Path where mem files are located. */
-	snprintf (procdir, PATH_MAX, "/proc/%u/fd/", pid);
-	/* Maps file used to locate mem file. */
-	snprintf (mapfile, PATH_MAX, "/proc/%u/maps", pid);
-
-	fmap = fopen(mapfile, "r");
-	if (fmap == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open maps file for pid %d\n", dev->device_fh, pid);
-		return -1;
-	}
-
-	/* Read through maps file until we find out base_address. */
-	while (fgets(line, BUFSIZE, fmap) != 0) {
-		str = line;
-		errno = 0;
-		/* Split line in to fields. */
-		for (i = 0; i < PROCMAP_SZ; i++) {
-			if (((in[i] = strtok_r(str, &dlm[i], &sp)) == NULL) || (errno != 0)) {
-				fclose(fmap);
-				return -1;
-			}
-			str = NULL;
-		}
-
-		/* Convert/Copy each field as needed. */
-		procmap.va_start = strtoull(in[0], &end, 16);
-		if ((in[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.len = strtoull(in[1], &end, 16);
-		if ((in[1] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.pgoff = strtoull(in[3], &end, 16);
-		if ((in[3] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.maj = strtoul(in[4], &end, 16);
-		if ((in[4] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.min = strtoul(in[5], &end, 16);
-		if ((in[5] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.ino = strtoul(in[6], &end, 16);
-		if ((in[6] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		memcpy(&procmap.prot, in[2], PROT_SZ);
-		memcpy(&procmap.fname, in[7], PATH_MAX);
-
-		if (procmap.va_start == addr) {
-			procmap.len = procmap.len - procmap.va_start;
-			found = 1;
-			break;
-		}
-	}
-	fclose(fmap);
-
-	if (!found) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find memory file in pid %d maps file\n", dev->device_fh, pid);
-		return -1;
-	}
-
-	/* Find the guest memory file among the process fds. */
-	dp = opendir(procdir);
-	if (dp == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Cannot open pid %d process directory \n", dev->device_fh, pid);
-		return -1;
-
-	}
-
-	found = 0;
-
-	/* Read the fd directory contents. */
-	while (NULL != (dptr = readdir(dp))) {
-		snprintf (memfile, PATH_MAX, "/proc/%u/fd/%s", pid, dptr->d_name);
-	    realpath(memfile, resolved_path);
-		if (resolved_path == NULL) {
-			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to resolve fd directory\n", dev->device_fh);
-			closedir(dp);
-			return -1;
-		}
-		if (strncmp(resolved_path, procmap.fname,
-			strnlen(procmap.fname, PATH_MAX)) == 0) {
-			found = 1;
-			break;
-		}
-	}
-
-	closedir(dp);
-
-	if (found == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find memory file for pid %d\n", dev->device_fh, pid);
-		return -1;
-	}
-	/* Open the shared memory file and map the memory into this process. */
-	fd = open(memfile, O_RDWR);
-
-	if (fd == -1) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open %s for pid %d\n", dev->device_fh, memfile, pid);
-		return -1;
-	}
-
-	map = mmap(0, (size_t)procmap.len, PROT_READ|PROT_WRITE , MAP_POPULATE|MAP_SHARED, fd, 0);
-	close (fd);
-
-	if (map == MAP_FAILED) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Error mapping the file %s for pid %d\n",  dev->device_fh, memfile, pid);
-		return -1;
-	}
-
-	/* Store the memory address and size in the device data structure */
-	mem->mapped_address = (uint64_t)(uintptr_t)map;
-	mem->mapped_size = procmap.len;
-
-	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mem File: %s->%s - Size: %llu - VA: %p\n", dev->device_fh,
-		memfile, resolved_path, (long long unsigned)mem->mapped_size, map);
-
-	return 0;
-}
-
-/*
- * Retrieves an entry from the devices configuration linked list.
- */
-static struct virtio_net_config_ll *
-get_config_ll_entry(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *ll_dev = ll_root;
-
-	/* Loop through linked list until the device_fh is found. */
-	while (ll_dev != NULL) {
-		if (ll_dev->dev.device_fh == ctx.fh)
-			return ll_dev;
-		ll_dev = ll_dev->next;
-	}
-
-	return NULL;
-}
-
-/*
- * Searches the configuration core linked list and retrieves the device if it exists.
- */
-static struct virtio_net *
-get_device(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *ll_dev;
-
-	ll_dev = get_config_ll_entry(ctx);
-
-	/* If a matching entry is found in the linked list, return the device in that entry. */
-	if (ll_dev) {
-		return &ll_dev->dev;
-	}
-
-	RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Device not found in linked list.\n", ctx.fh);
-	return NULL;
-}
-
-/*
- * Add entry containing a device to the device configuration linked list.
- */
-static void
-add_config_ll_entry(struct virtio_net_config_ll *new_ll_dev)
-{
-	struct virtio_net_config_ll *ll_dev = ll_root;
-
-	/* If ll_dev == NULL then this is the first device so go to else */
-	if (ll_dev) {
-		/* If the 1st device_fh != 0 then we insert our device here. */
-		if (ll_dev->dev.device_fh != 0)	{
-			new_ll_dev->dev.device_fh = 0;
-			new_ll_dev->next = ll_dev;
-			ll_root = new_ll_dev;
-		} else {
-			/* Increment through the ll until we find un unused device_fh. Insert the device at that entry*/
-			while ((ll_dev->next != NULL) && (ll_dev->dev.device_fh == (ll_dev->next->dev.device_fh - 1)))
-				ll_dev = ll_dev->next;
-
-			new_ll_dev->dev.device_fh = ll_dev->dev.device_fh + 1;
-			new_ll_dev->next = ll_dev->next;
-			ll_dev->next = new_ll_dev;
-		}
-	} else {
-		ll_root = new_ll_dev;
-		ll_root->dev.device_fh = 0;
-	}
-
-}
-
-/*
- * Unmap any memory, close any file descriptors and free any memory owned by a device.
- */
-static void
-cleanup_device(struct virtio_net *dev)
-{
-	/* Unmap QEMU memory file if mapped. */
-	if (dev->mem) {
-		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
-		if (dev->mem->regions_hpa)
-			free(dev->mem->regions_hpa);
-		free(dev->mem);
-	}
-
-	/* Close any event notifiers opened by device. */
-	if (dev->virtqueue[VIRTIO_RXQ]->callfd)
-		close((int)dev->virtqueue[VIRTIO_RXQ]->callfd);
-	if (dev->virtqueue[VIRTIO_RXQ]->kickfd)
-		close((int)dev->virtqueue[VIRTIO_RXQ]->kickfd);
-	if (dev->virtqueue[VIRTIO_TXQ]->callfd)
-		close((int)dev->virtqueue[VIRTIO_TXQ]->callfd);
-	if (dev->virtqueue[VIRTIO_TXQ]->kickfd)
-		close((int)dev->virtqueue[VIRTIO_TXQ]->kickfd);
-}
-
-/*
- * Release virtqueues and device memory.
- */
-static void
-free_device(struct virtio_net_config_ll *ll_dev)
-{
-	/* Free any malloc'd memory */
-	free(ll_dev->dev.virtqueue[VIRTIO_RXQ]);
-	free(ll_dev->dev.virtqueue[VIRTIO_TXQ]);
-	free(ll_dev);
-}
-/*
- * Remove an entry from the device configuration linked list.
- */
-static struct virtio_net_config_ll *
-rm_config_ll_entry(struct virtio_net_config_ll *ll_dev, struct virtio_net_config_ll *ll_dev_last)
-{
-	/* First remove the device and then clean it up. */
-	if (ll_dev == ll_root) {
-		ll_root = ll_dev->next;
-		cleanup_device(&ll_dev->dev);
-		free_device(ll_dev);
-		return ll_root;
-	} else {
-		if (likely(ll_dev_last != NULL)) {
-			ll_dev_last->next = ll_dev->next;
-			cleanup_device(&ll_dev->dev);
-			free_device(ll_dev);
-			return ll_dev_last->next;
-		} else {
-			cleanup_device(&ll_dev->dev);
-			free_device(ll_dev);
-			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry from config_ll failed\n");
-			return NULL;
-		}
-	}
-}
-
-/*
- *  Initialise all variables in device structure.
- */
-static void
-init_device(struct virtio_net *dev)
-{
-	uint64_t vq_offset;
-
-	/* Virtqueues have already been malloced so we don't want to set them to NULL. */
-	vq_offset = offsetof(struct virtio_net, mem);
-
-	/* Set everything to 0. */
-	memset((void*)(uintptr_t)((uint64_t)(uintptr_t)dev + vq_offset), 0,
-		(sizeof(struct virtio_net) - (size_t)vq_offset));
-	memset(dev->virtqueue[VIRTIO_RXQ], 0, sizeof(struct vhost_virtqueue));
-	memset(dev->virtqueue[VIRTIO_TXQ], 0, sizeof(struct vhost_virtqueue));
-
-	/* Backends are set to -1 indicating an inactive device. */
-	dev->virtqueue[VIRTIO_RXQ]->backend = VIRTIO_DEV_STOPPED;
-	dev->virtqueue[VIRTIO_TXQ]->backend = VIRTIO_DEV_STOPPED;
-}
-
-/*
- * Function is called from the CUSE open function. The device structure is
- * initialised and a new entry is added to the device configuration linked
- * list.
- */
-static int
-new_device(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *new_ll_dev;
-	struct vhost_virtqueue *virtqueue_rx, *virtqueue_tx;
-
-	/*check the number of devices in the system*/
-	if (num_cur_devices == num_devices) {
-		RTE_LOG(ERR, VHOST_CONFIG, "() Max num devices (%u) exceeded\n", num_devices);
-		return -1;
-	}
-
-	/* Setup device and virtqueues. */
-	new_ll_dev = malloc(sizeof(struct virtio_net_config_ll));
-	if (new_ll_dev == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev.\n", ctx.fh);
-		return -1;
-	}
-
-	virtqueue_rx = malloc(sizeof(struct vhost_virtqueue));
-	if (virtqueue_rx == NULL) {
-		free(new_ll_dev);
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_rx.\n", ctx.fh);
-		return -1;
-	}
-
-	virtqueue_tx = malloc(sizeof(struct vhost_virtqueue));
-	if (virtqueue_tx == NULL) {
-		free(virtqueue_rx);
-		free(new_ll_dev);
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_tx.\n", ctx.fh);
-		return -1;
-	}
-
-	new_ll_dev->dev.virtqueue[VIRTIO_RXQ] = virtqueue_rx;
-	new_ll_dev->dev.virtqueue[VIRTIO_TXQ] = virtqueue_tx;
-
-	/* Initialise device and virtqueues. */
-	init_device(&new_ll_dev->dev);
-
-	new_ll_dev->next = NULL;
-
-	/* Add entry to device configuration linked list. */
-	add_config_ll_entry(new_ll_dev);
-
-	/*increment the number of devices in the system*/
-	num_cur_devices++;
-
-	return new_ll_dev->dev.device_fh;
-}
-
-/*
- * Function is called from the CUSE release function. This function will cleanup
- * the device and remove it from device configuration linked list.
- */
-static void
-destroy_device(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *ll_dev_cur_ctx, *ll_dev_last = NULL;
-	struct virtio_net_config_ll *ll_dev_cur = ll_root;
-
-	/* Find the linked list entry for the device to be removed. */
-	ll_dev_cur_ctx = get_config_ll_entry(ctx);
-	while (ll_dev_cur != NULL) {
-		/* If the device is found or a device that doesn't exist is found then it is removed. */
-		if (ll_dev_cur == ll_dev_cur_ctx) {
-			/*
-			 * If the device is running on a data core then call the function to remove it from
-			 * the data core.
-			 */
-			if ((ll_dev_cur->dev.flags & VIRTIO_DEV_RUNNING))
-				notify_ops->destroy_device(&(ll_dev_cur->dev));
-			ll_dev_cur = rm_config_ll_entry(ll_dev_cur, ll_dev_last);
-		} else {
-			ll_dev_last = ll_dev_cur;
-			ll_dev_cur = ll_dev_cur->next;
-		}
-	}
-
-	/*decrement the number of devices in the system*/
-	num_cur_devices--;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_OWNER
- * This function just returns success at the moment unless the device hasn't been initialised.
- */
-static int
-set_owner(struct vhost_device_ctx ctx)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_RESET_OWNER
- */
-static int
-reset_owner(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *ll_dev;
-
-	ll_dev = get_config_ll_entry(ctx);
-
-	cleanup_device(&ll_dev->dev);
-	init_device(&ll_dev->dev);
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_GET_FEATURES
- * The features that we support are requested.
- */
-static int
-get_features(struct vhost_device_ctx ctx, uint64_t *pu)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* Send our supported features. */
-	*pu = VHOST_FEATURES;
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_FEATURES
- * We receive the negotiated set of features supported by us and the virtio device.
- */
-static int
-set_features(struct vhost_device_ctx ctx, uint64_t *pu)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-	if (*pu & ~VHOST_FEATURES)
-		return -1;
-
-	/* Store the negotiated feature list for the device. */
-	dev->features = *pu;
-
-	/* Set the vhost_hlen depending on if VIRTIO_NET_F_MRG_RXBUF is set. */
-	if (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers enabled\n", dev->device_fh);
-		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
-		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
-	} else {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers disabled\n", dev->device_fh);
-		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
-		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
-	}
-	return 0;
-}
-
-/*
- * Calculate the region count of physical continous regions for one particular
- * region of whose vhost virtual address is continous. The particular region
- * start from vva_start, with size of 'size' in argument.
- */
-static uint32_t check_hpa_regions(uint64_t vva_start, uint64_t size)
-{
-	uint32_t i, nregions = 0, page_size = PAGE_SIZE;
-	uint64_t cur_phys_addr = 0, next_phys_addr = 0;
-	if (vva_start % page_size) {
-		LOG_DEBUG(VHOST_CONFIG,
-			"in check_countinous: vva start(%p) mod page_size(%d) "
-			"has remainder\n",
-			(void *)(uintptr_t)vva_start, page_size);
-		return 0;
-	}
-	if (size % page_size) {
-		LOG_DEBUG(VHOST_CONFIG,
-			"in check_countinous: "
-			"size((%"PRIu64")) mod page_size(%d) has remainder\n",
-			size, page_size);
-		return 0;
-	}
-	for (i = 0; i < size - page_size; i = i + page_size) {
-		cur_phys_addr
-			= rte_mem_virt2phy((void *)(uintptr_t)(vva_start + i));
-		next_phys_addr = rte_mem_virt2phy(
-			(void *)(uintptr_t)(vva_start + i + page_size));
-		if ((cur_phys_addr + page_size) != next_phys_addr) {
-			++nregions;
-			LOG_DEBUG(VHOST_CONFIG,
-				"in check_continuous: hva addr:(%p) is not "
-				"continuous with hva addr:(%p), diff:%d\n",
-				(void *)(uintptr_t)(vva_start + (uint64_t)i),
-				(void *)(uintptr_t)(vva_start + (uint64_t)i
-				+ page_size), page_size);
-			LOG_DEBUG(VHOST_CONFIG,
-				"in check_continuous: hpa addr:(%p) is not "
-				"continuous with hpa addr:(%p), "
-				"diff:(%"PRIu64")\n",
-				(void *)(uintptr_t)cur_phys_addr,
-				(void *)(uintptr_t)next_phys_addr,
-				(next_phys_addr-cur_phys_addr));
-		}
-	}
-	return nregions;
-}
-
-/*
- * Divide each region whose vhost virtual address is continous into a few
- * sub-regions, make sure the physical address within each sub-region are
- * continous. And fill offset(to GPA) and size etc. information of each
- * sub-region into regions_hpa.
- */
-static uint32_t fill_hpa_memory_regions(void *memory)
-{
-	uint32_t regionidx, regionidx_hpa = 0, i, k, page_size = PAGE_SIZE;
-	uint64_t cur_phys_addr = 0, next_phys_addr = 0, vva_start;
-	struct virtio_memory *virtio_memory = (struct virtio_memory *)memory;
-	struct virtio_memory_regions_hpa *mem_region_hpa
-		= virtio_memory->regions_hpa;
-
-	if (mem_region_hpa == NULL)
-		return 0;
-
-	for (regionidx = 0; regionidx < virtio_memory->nregions; regionidx++) {
-		vva_start = virtio_memory->regions[regionidx].guest_phys_address
-			+ virtio_memory->regions[regionidx].address_offset;
-		mem_region_hpa[regionidx_hpa].guest_phys_address
-			= virtio_memory->regions[regionidx].guest_phys_address;
-		mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
-			rte_mem_virt2phy((void *)(uintptr_t)(vva_start))
-			- mem_region_hpa[regionidx_hpa].guest_phys_address;
-		LOG_DEBUG(VHOST_CONFIG,
-			"in fill_hpa_regions: guest phys addr start[%d]:(%p)\n",
-			regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].guest_phys_address));
-		LOG_DEBUG(VHOST_CONFIG,
-			"in fill_hpa_regions: host  phys addr start[%d]:(%p)\n",
-			regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
-		for (i = 0, k = 0;
-			i < virtio_memory->regions[regionidx].memory_size
-				- page_size;
-			i += page_size) {
-			cur_phys_addr = rte_mem_virt2phy(
-					(void *)(uintptr_t)(vva_start + i));
-			next_phys_addr = rte_mem_virt2phy(
-					(void *)(uintptr_t)(vva_start
-					+ i + page_size));
-			if ((cur_phys_addr + page_size) != next_phys_addr) {
-				mem_region_hpa[regionidx_hpa].guest_phys_address_end =
-					mem_region_hpa[regionidx_hpa].guest_phys_address
-					+ k + page_size;
-				mem_region_hpa[regionidx_hpa].memory_size
-					= k + page_size;
-				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest "
-					"phys addr end  [%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
-				LOG_DEBUG(VHOST_CONFIG,
-					"in fill_hpa_regions: guest phys addr "
-					"size [%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].memory_size));
-				mem_region_hpa[regionidx_hpa + 1].guest_phys_address
-					= mem_region_hpa[regionidx_hpa].guest_phys_address_end;
-				++regionidx_hpa;
-				mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
-					next_phys_addr
-					- mem_region_hpa[regionidx_hpa].guest_phys_address;
-				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest"
-					" phys addr start[%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].guest_phys_address));
-				LOG_DEBUG(VHOST_CONFIG,
-					"in fill_hpa_regions: host  phys addr "
-					"start[%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
-				k = 0;
-			} else {
-				k += page_size;
-			}
-		}
-		mem_region_hpa[regionidx_hpa].guest_phys_address_end
-			= mem_region_hpa[regionidx_hpa].guest_phys_address
-			+ k + page_size;
-		mem_region_hpa[regionidx_hpa].memory_size = k + page_size;
-		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr end  "
-			"[%d]:(%p)\n", regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
-		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr size "
-			"[%d]:(%p)\n", regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].memory_size));
-		++regionidx_hpa;
-	}
-	return regionidx_hpa;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_MEM_TABLE
- * This function creates and populates the memory structure for the device. This includes
- * storing offsets used to translate buffer addresses.
- */
-static int
-set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_t nregions)
-{
-	struct virtio_net *dev;
-	struct vhost_memory_region *mem_regions;
-	struct virtio_memory *mem;
-	uint64_t size = offsetof(struct vhost_memory, regions);
-	uint32_t regionidx, valid_regions;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	if (dev->mem) {
-		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
-		free(dev->mem);
-	}
-
-	/* Malloc the memory structure depending on the number of regions. */
-	mem = calloc(1, sizeof(struct virtio_memory) + (sizeof(struct virtio_memory_regions) * nregions));
-	if (mem == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev->mem.\n", dev->device_fh);
-		return -1;
-	}
-
-	mem->nregions = nregions;
-
-	mem_regions = (void*)(uintptr_t)((uint64_t)(uintptr_t)mem_regions_addr + size);
-
-	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
-		/* Populate the region structure for each region. */
-		mem->regions[regionidx].guest_phys_address = mem_regions[regionidx].guest_phys_addr;
-		mem->regions[regionidx].guest_phys_address_end = mem->regions[regionidx].guest_phys_address +
-			mem_regions[regionidx].memory_size;
-		mem->regions[regionidx].memory_size = mem_regions[regionidx].memory_size;
-		mem->regions[regionidx].userspace_address = mem_regions[regionidx].userspace_addr;
-
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") REGION: %u - GPA: %p - QEMU VA: %p - SIZE (%"PRIu64")\n", dev->device_fh,
-				regionidx, (void*)(uintptr_t)mem->regions[regionidx].guest_phys_address,
-				(void*)(uintptr_t)mem->regions[regionidx].userspace_address,
-				mem->regions[regionidx].memory_size);
-
-		/*set the base address mapping*/
-		if (mem->regions[regionidx].guest_phys_address == 0x0) {
-			mem->base_address = mem->regions[regionidx].userspace_address;
-			/* Map VM memory file */
-			if (host_memory_map(dev, mem, ctx.pid, mem->base_address) != 0) {
-				free(mem);
-				return -1;
-			}
-		}
-	}
-
-	/* Check that we have a valid base address. */
-	if (mem->base_address == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find base address of qemu memory file.\n", dev->device_fh);
-		free(mem);
-		return -1;
-	}
-
-	/* Check if all of our regions have valid mappings. Usually one does not exist in the QEMU memory file. */
-	valid_regions = mem->nregions;
-	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
-		if ((mem->regions[regionidx].userspace_address < mem->base_address) ||
-			(mem->regions[regionidx].userspace_address > (mem->base_address + mem->mapped_size)))
-				valid_regions--;
-	}
-
-	/* If a region does not have a valid mapping we rebuild our memory struct to contain only valid entries. */
-	if (valid_regions != mem->nregions) {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Not all memory regions exist in the QEMU mem file. Re-populating mem structure\n",
-			dev->device_fh);
-
-		/* Re-populate the memory structure with only valid regions. Invalid regions are over-written with memmove. */
-		valid_regions = 0;
-
-		for (regionidx = mem->nregions; 0 != regionidx--;) {
-			if ((mem->regions[regionidx].userspace_address < mem->base_address) ||
-					(mem->regions[regionidx].userspace_address > (mem->base_address + mem->mapped_size))) {
-				memmove(&mem->regions[regionidx], &mem->regions[regionidx + 1],
-					sizeof(struct virtio_memory_regions) * valid_regions);
-			} else {
-				valid_regions++;
-			}
-		}
-	}
-	mem->nregions = valid_regions;
-	mem->nregions_hpa = mem->nregions;
-	dev->mem = mem;
-
-	/*
-	 * Calculate the address offset for each region. This offset is used to identify the vhost virtual address
-	 * corresponding to a QEMU guest physical address.
-	 */
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		dev->mem->regions[regionidx].address_offset = dev->mem->regions[regionidx].userspace_address - dev->mem->base_address
-			+ dev->mem->mapped_address - dev->mem->regions[regionidx].guest_phys_address;
-
-		dev->mem->nregions_hpa
-			+= check_hpa_regions(
-				dev->mem->regions[regionidx].guest_phys_address
-				+ dev->mem->regions[regionidx].address_offset,
-				dev->mem->regions[regionidx].memory_size);
-	}
-	if (dev->mem->regions_hpa != NULL) {
-		free(dev->mem->regions_hpa);
-		dev->mem->regions_hpa = NULL;
-	}
-
-	dev->mem->regions_hpa = (struct virtio_memory_regions_hpa *) calloc(1,
-		(sizeof(struct virtio_memory_regions_hpa)
-		* dev->mem->nregions_hpa));
-	if (dev->mem->regions_hpa == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to allocate memory for "
-			"dev->mem->regions_hpa.\n", dev->device_fh);
-		return -1;
-	}
-	if (fill_hpa_memory_regions(
-		(void *)dev->mem) != dev->mem->nregions_hpa) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"in set_mem_table: hpa memory regions number mismatch: "
-			"[%d]\n", dev->mem->nregions_hpa);
-		return -1;
-	}
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_NUM
- * The virtio device sends us the size of the descriptor ring.
- */
-static int
-set_vring_num(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	dev->virtqueue[state->index]->size = state->num;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_ADDR
- * The virtio device sends us the desc, used and avail ring addresses. This function
- * then converts these to our address space.
- */
-static int
-set_vring_addr(struct vhost_device_ctx ctx, struct vhost_vring_addr *addr)
-{
-	struct virtio_net *dev;
-	struct vhost_virtqueue *vq;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* addr->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	vq = dev->virtqueue[addr->index];
-
-	/* The addresses are converted from QEMU virtual to Vhost virtual. */
-	vq->desc = (struct vring_desc*)(uintptr_t)qva_to_vva(dev, addr->desc_user_addr);
-	if (vq->desc == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find descriptor ring address.\n", dev->device_fh);
-		return -1;
-	}
-
-	vq->avail = (struct vring_avail*)(uintptr_t)qva_to_vva(dev, addr->avail_user_addr);
-	if (vq->avail == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find available ring address.\n", dev->device_fh);
-		return -1;
-	}
-
-	vq->used = (struct vring_used*)(uintptr_t)qva_to_vva(dev, addr->used_user_addr);
-	if (vq->used == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find used ring address.\n", dev->device_fh);
-		return -1;
-	}
-
-	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address desc: %p\n", dev->device_fh, vq->desc);
-	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address avail: %p\n", dev->device_fh, vq->avail);
-	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address used: %p\n", dev->device_fh, vq->used);
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_BASE
- * The virtio device sends us the available ring last used index.
- */
-static int
-set_vring_base(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	dev->virtqueue[state->index]->last_used_idx = state->num;
-	dev->virtqueue[state->index]->last_used_idx_res = state->num;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_GET_VRING_BASE
- * We send the virtio device our available ring last used index.
- */
-static int
-get_vring_base(struct vhost_device_ctx ctx, uint32_t index, struct vhost_vring_state *state)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	state->index = index;
-	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	state->num = dev->virtqueue[state->index]->last_used_idx;
-
-	return 0;
-}
-
-/*
- * This function uses the eventfd_link kernel module to copy an eventfd file descriptor
- * provided by QEMU in to our process space.
- */
-static int
-eventfd_copy(struct virtio_net *dev, struct eventfd_copy *eventfd_copy)
-{
-	int eventfd_link, ret;
-
-	/* Open the character device to the kernel module. */
-	eventfd_link = open(eventfd_cdev, O_RDWR);
-	if (eventfd_link < 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") eventfd_link module is not loaded\n",  dev->device_fh);
-		return -1;
-	}
-
-	/* Call the IOCTL to copy the eventfd. */
-	ret = ioctl(eventfd_link, EVENTFD_COPY, eventfd_copy);
-	close(eventfd_link);
-
-	if (ret < 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") EVENTFD_COPY ioctl failed\n",  dev->device_fh);
-		return -1;
-	}
-
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_CALL
- * The virtio device sends an eventfd to interrupt the guest. This fd gets copied in
- * to our process space.
- */
-static int
-set_vring_call(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
-{
-	struct virtio_net *dev;
-	struct eventfd_copy	eventfd_kick;
-	struct vhost_virtqueue *vq;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	vq = dev->virtqueue[file->index];
-
-	if (vq->kickfd)
-		close((int)vq->kickfd);
-
-	/* Populate the eventfd_copy structure and call eventfd_copy. */
-	vq->kickfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
-	eventfd_kick.source_fd = vq->kickfd;
-	eventfd_kick.target_fd = file->fd;
-	eventfd_kick.target_pid = ctx.pid;
-
-	if (eventfd_copy(dev, &eventfd_kick))
-		return -1;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_KICK
- * The virtio device sends an eventfd that it can use to notify us. This fd gets copied in
- * to our process space.
- */
-static int
-set_vring_kick(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
-{
-	struct virtio_net *dev;
-	struct eventfd_copy eventfd_call;
-	struct vhost_virtqueue *vq;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	vq = dev->virtqueue[file->index];
-
-	if (vq->callfd)
-		close((int)vq->callfd);
-
-	/* Populate the eventfd_copy structure and call eventfd_copy. */
-	vq->callfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
-	eventfd_call.source_fd = vq->callfd;
-	eventfd_call.target_fd = file->fd;
-	eventfd_call.target_pid = ctx.pid;
-
-	if (eventfd_copy(dev, &eventfd_call))
-        return -1;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_NET_SET_BACKEND
- * To complete device initialisation when the virtio driver is loaded we are provided with a
- * valid fd for a tap device (not used by us). If this happens then we can add the device to a
- * data core. When the virtio driver is removed we get fd=-1. At that point we remove the device
- * from the data core. The device will still exist in the device configuration linked list.
- */
-static int
-set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL) {
-		return -1;
-	}
-
-	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	dev->virtqueue[file->index]->backend = file->fd;
-
-	/* If the device isn't already running and both backend fds are set we add the device. */
-	if (!(dev->flags & VIRTIO_DEV_RUNNING)) {
-		if (((int)dev->virtqueue[VIRTIO_TXQ]->backend != VIRTIO_DEV_STOPPED) &&
-			((int)dev->virtqueue[VIRTIO_RXQ]->backend != VIRTIO_DEV_STOPPED))
-			return notify_ops->new_device(dev);
-	/* Otherwise we remove it. */
-	} else
-		if (file->fd == VIRTIO_DEV_STOPPED) {
-			notify_ops->destroy_device(dev);
-		}
-	return 0;
-}
-
-/*
- * Function pointers are set for the device operations to allow CUSE to call functions
- * when an IOCTL, device_add or device_release is received.
- */
-static const struct vhost_net_device_ops vhost_device_ops =
-{
-	.new_device = new_device,
-	.destroy_device = destroy_device,
-
-	.get_features = get_features,
-	.set_features = set_features,
-
-	.set_mem_table = set_mem_table,
-
-	.set_vring_num = set_vring_num,
-	.set_vring_addr = set_vring_addr,
-	.set_vring_base = set_vring_base,
-	.get_vring_base = get_vring_base,
-
-	.set_vring_kick = set_vring_kick,
-	.set_vring_call = set_vring_call,
-
-	.set_backend = set_backend,
-
-	.set_owner = set_owner,
-	.reset_owner = reset_owner,
-};
-
-/*
- * Called by main to setup callbacks when registering CUSE device.
- */
-struct vhost_net_device_ops const *
-get_virtio_net_callbacks(void)
-{
-	return &vhost_device_ops;
-}
-
-/*
- * Register ops so that we can add/remove device to data core.
- */
-int
-init_virtio_net(struct virtio_net_device_ops const * const ops)
-{
-	notify_ops = ops;
-
-	return 0;
-}
-
-/*
- * Currently not used as we Ctrl+c to exit application.
- */
-int
-deinit_virtio_net(void)
-{
-	return 0;
-}
diff --git a/examples/vhost/virtio-net.h b/examples/vhost/virtio-net.h
deleted file mode 100644
index 1a2f0dc..0000000
--- a/examples/vhost/virtio-net.h
+++ /dev/null
@@ -1,161 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _VIRTIO_NET_H_
-#define _VIRTIO_NET_H_
-
-/* Used to indicate that the device is running on a data core */
-#define VIRTIO_DEV_RUNNING 1
-
-/* Backend value set by guest. */
-#define VIRTIO_DEV_STOPPED -1
-
-#define PAGE_SIZE   4096
-
-/* Enum for virtqueue management. */
-enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
-
-#define BUF_VECTOR_MAX 256
-
-/*
- * Structure contains buffer address, length and descriptor index
- * from vring to do scatter RX.
-*/
-struct buf_vector {
-uint64_t buf_addr;
-uint32_t buf_len;
-uint32_t desc_idx;
-};
-
-/*
- * Structure contains variables relevant to TX/RX virtqueues.
- */
-struct vhost_virtqueue
-{
-	struct vring_desc	*desc;				/* Virtqueue descriptor ring. */
-	struct vring_avail	*avail;				/* Virtqueue available ring. */
-	struct vring_used	*used;				/* Virtqueue used ring. */
-	uint32_t			size;				/* Size of descriptor ring. */
-	uint32_t			backend;			/* Backend value to determine if device should started/stopped. */
-	uint16_t			vhost_hlen;			/* Vhost header length (varies depending on RX merge buffers. */
-	volatile uint16_t	last_used_idx;		/* Last index used on the available ring */
-	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
-	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
-	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
-	/* Used for scatter RX. */
-	struct buf_vector	buf_vec[BUF_VECTOR_MAX];
-} __rte_cache_aligned;
-
-/*
- * Device structure contains all configuration information relating to the device.
- */
-struct virtio_net
-{
-	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/* Contains all virtqueue information. */
-	struct virtio_memory 	*mem;						/* QEMU memory and memory region information. */
-	struct ether_addr 		mac_address;				/* Device MAC address (Obtained on first TX packet). */
-	uint64_t 				features;					/* Negotiated feature set. */
-	uint64_t 				device_fh;					/* device identifier. */
-	uint32_t 				vmdq_rx_q;					/* RX VMDQ queue number. */
-	uint32_t 				flags;						/* Device flags. Only used to check if device is running on data core. */
-	uint32_t 				vlan_tag;					/* Vlan tag for device. Currently set to device_id (0-63). */
-	uint16_t 				coreid;						/* Data core that the device is added to. */
-	volatile uint8_t 		ready;						/* A device is set as ready if the MAC address has been set. */
-	volatile uint8_t		remove;						/* Device is marked for removal from the data core. */
-} __rte_cache_aligned;
-
-/*
- * Device linked list structure for configuration.
- */
-struct virtio_net_config_ll
-{
-	struct virtio_net		dev;	/* Virtio device. */
-	struct virtio_net_config_ll	*next; /* Next entry on linked list. */
-};
-
-/*
- * Information relating to memory regions including offsets to addresses in QEMUs memory file.
- */
-struct virtio_memory_regions {
-	uint64_t	guest_phys_address;		/* Base guest physical address of region. */
-	uint64_t	guest_phys_address_end;	/* End guest physical address of region. */
-	uint64_t	memory_size;			/* Size of region. */
-	uint64_t	userspace_address;		/* Base userspace address of region. */
-	uint64_t	address_offset;			/* Offset of region for address translation. */
-};
-
-/*
- * Information relating to memory regions including offsets to
- * addresses in host physical space.
- */
-struct virtio_memory_regions_hpa {
-	/* Base guest physical address of region. */
-	uint64_t	guest_phys_address;
-	/* End guest physical address of region. */
-	uint64_t	guest_phys_address_end;
-	/* Size of region. */
-	uint64_t	memory_size;
-	/* Offset of region for gpa to hpa translation. */
-	uint64_t	host_phys_addr_offset;
-};
-
-/*
- * Memory structure includes region and mapping information.
- */
-struct virtio_memory {
-	uint64_t			base_address;			/* Base QEMU userspace address of the memory file. */
-	uint64_t			mapped_address;			/* Mapped address of memory file base in our applications memory space. */
-	uint64_t			mapped_size;			/* Total size of memory file. */
-	uint32_t			nregions;				/* Number of memory regions. */
-	 /* Number of memory regions for gpa to hpa translation. */
-	uint32_t			nregions_hpa;
-	/* Memory region information for gpa to hpa translation. */
-	struct virtio_memory_regions_hpa  *regions_hpa;
-	/* Memory region information. */
-	struct virtio_memory_regions      regions[0];
-};
-
-/*
- * Device operations to add/remove device.
- */
-struct virtio_net_device_ops {
-	int (* new_device) 		(struct virtio_net *);	/* Add device. */
-	void (* destroy_device)	(volatile struct virtio_net *);	/* Remove device. */
-};
-
-int init_virtio_net(struct virtio_net_device_ops const * const);
-int deinit_virtio_net(void);
-
-struct vhost_net_device_ops const * get_virtio_net_callbacks(void);
-
-#endif /* _VIRTIO_NET_H_ */
diff --git a/lib/librte_vhost/Makefile b/lib/librte_vhost/Makefile
new file mode 100644
index 0000000..f45f83f
--- /dev/null
+++ b/lib/librte_vhost/Makefile
@@ -0,0 +1,60 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+#   All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of Intel Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ifeq ($(RTE_SDK),)
+$(error "Please define RTE_SDK environment variable")
+endif
+
+# Default target, can be overriden by command line or environment
+RTE_TARGET ?= x86_64-native-linuxapp-gcc
+
+include $(RTE_SDK)/mk/rte.vars.mk
+
+ifneq ($(CONFIG_RTE_EXEC_ENV),"linuxapp")
+$(info This application can only operate in a linuxapp environment, \
+please change the definition of the RTE_TARGET environment variable)
+all:
+else
+
+# binary name
+APP = vhost-switch
+
+# all source are stored in SRCS-y
+#SRCS-y := cusedrv.c loopback-userspace.c
+SRCS-y := main.c virtio-net.c vhost-net-cdev.c
+
+CFLAGS += -O2 -I/usr/local/include -D_FILE_OFFSET_BITS=64 -Wno-unused-parameter
+CFLAGS += $(WERROR_FLAGS)
+LDFLAGS += -lfuse
+
+include $(RTE_SDK)/mk/rte.extapp.mk
+
+endif
diff --git a/lib/librte_vhost/eventfd_link/Makefile b/lib/librte_vhost/eventfd_link/Makefile
new file mode 100644
index 0000000..fc3927b
--- /dev/null
+++ b/lib/librte_vhost/eventfd_link/Makefile
@@ -0,0 +1,39 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+#   All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of Intel Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+obj-m += eventfd_link.o
+
+
+all:
+	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
+
+clean:
+	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
diff --git a/lib/librte_vhost/eventfd_link/eventfd_link.c b/lib/librte_vhost/eventfd_link/eventfd_link.c
new file mode 100644
index 0000000..fc0653a
--- /dev/null
+++ b/lib/librte_vhost/eventfd_link/eventfd_link.c
@@ -0,0 +1,205 @@
+/*-
+ *  * GPL LICENSE SUMMARY
+ *  *
+ *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *  *
+ *  *   This program is free software; you can redistribute it and/or modify
+ *  *   it under the terms of version 2 of the GNU General Public License 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 the Free Software
+ *  *   Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *  *   The full GNU General Public License is included in this distribution
+ *  *   in the file called LICENSE.GPL.
+ *  *
+ *  *   Contact Information:
+ *  *   Intel Corporation
+ *   */
+
+#include <linux/eventfd.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/rcupdate.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/mmu_context.h>
+#include <linux/sched.h>
+#include <asm/mmu_context.h>
+#include <linux/fdtable.h>
+
+#include "eventfd_link.h"
+
+
+/*
+ * get_files_struct is copied from fs/file.c
+ */
+struct files_struct *
+get_files_struct (struct task_struct *task)
+{
+	struct files_struct *files;
+
+	task_lock (task);
+	files = task->files;
+	if (files)
+		atomic_inc (&files->count);
+	task_unlock (task);
+
+	return files;
+}
+
+/*
+ * put_files_struct is extracted from fs/file.c
+ */
+void
+put_files_struct (struct files_struct *files)
+{
+	if (atomic_dec_and_test (&files->count))
+	{
+		BUG ();
+	}
+}
+
+
+static long
+eventfd_link_ioctl (struct file *f, unsigned int ioctl, unsigned long arg)
+{
+	void __user *argp = (void __user *) arg;
+	struct task_struct *task_target = NULL;
+	struct file *file;
+	struct files_struct *files;
+	struct fdtable *fdt;
+	struct eventfd_copy eventfd_copy;
+
+	switch (ioctl)
+	{
+		case EVENTFD_COPY:
+			if (copy_from_user (&eventfd_copy, argp, sizeof (struct eventfd_copy)))
+				return -EFAULT;
+
+			/*
+			 * Find the task struct for the target pid
+			 */
+			task_target =
+				pid_task (find_vpid (eventfd_copy.target_pid), PIDTYPE_PID);
+			if (task_target == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get mem ctx for target pid\n");
+				return -EFAULT;
+			}
+
+			files = get_files_struct (current);
+			if (files == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get files struct\n");
+				return -EFAULT;
+			}
+
+			rcu_read_lock ();
+			file = fcheck_files (files, eventfd_copy.source_fd);
+			if (file)
+			{
+				if (file->f_mode & FMODE_PATH
+						|| !atomic_long_inc_not_zero (&file->f_count))
+					file = NULL;
+			}
+			rcu_read_unlock ();
+			put_files_struct (files);
+
+			if (file == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get file from source pid\n");
+				return 0;
+			}
+
+			/*
+			 * Release the existing eventfd in the source process
+			 */
+			spin_lock (&files->file_lock);
+			filp_close (file, files);
+			fdt = files_fdtable (files);
+			fdt->fd[eventfd_copy.source_fd] = NULL;
+			spin_unlock (&files->file_lock);
+
+			/*
+			 * Find the file struct associated with the target fd.
+			 */
+
+			files = get_files_struct (task_target);
+			if (files == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get files struct\n");
+				return -EFAULT;
+			}
+
+			rcu_read_lock ();
+			file = fcheck_files (files, eventfd_copy.target_fd);
+			if (file)
+			{
+				if (file->f_mode & FMODE_PATH
+						|| !atomic_long_inc_not_zero (&file->f_count))
+					file = NULL;
+			}
+			rcu_read_unlock ();
+			put_files_struct (files);
+
+			if (file == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get file from target pid\n");
+				return 0;
+			}
+
+
+			/*
+			 * Install the file struct from the target process into the
+			 * file desciptor of the source process,
+			 */
+
+			fd_install (eventfd_copy.source_fd, file);
+
+			return 0;
+
+		default:
+			return -ENOIOCTLCMD;
+	}
+}
+
+static const struct file_operations eventfd_link_fops = {
+	.owner = THIS_MODULE,
+	.unlocked_ioctl = eventfd_link_ioctl,
+};
+
+
+static struct miscdevice eventfd_link_misc = {
+	.name = "eventfd-link",
+	.fops = &eventfd_link_fops,
+};
+
+static int __init
+eventfd_link_init (void)
+{
+	return misc_register (&eventfd_link_misc);
+}
+
+module_init (eventfd_link_init);
+
+static void __exit
+eventfd_link_exit (void)
+{
+	misc_deregister (&eventfd_link_misc);
+}
+
+module_exit (eventfd_link_exit);
+
+MODULE_VERSION ("0.0.1");
+MODULE_LICENSE ("GPL v2");
+MODULE_AUTHOR ("Anthony Fee");
+MODULE_DESCRIPTION ("Link eventfd");
+MODULE_ALIAS ("devname:eventfd-link");
diff --git a/lib/librte_vhost/eventfd_link/eventfd_link.h b/lib/librte_vhost/eventfd_link/eventfd_link.h
new file mode 100644
index 0000000..a32a8dd
--- /dev/null
+++ b/lib/librte_vhost/eventfd_link/eventfd_link.h
@@ -0,0 +1,79 @@
+/*-
+ *  * This file is provided under a dual BSD/GPLv2 license.  When using or
+ *  *   redistributing this file, you may do so under either license.
+ *  *
+ *  *   GPL LICENSE SUMMARY
+ *  *
+ *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *  *
+ *  *   This program is free software; you can redistribute it and/or modify
+ *  *   it under the terms of version 2 of the GNU General Public License 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 the Free Software
+ *  *   Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *  *   The full GNU General Public License is included in this distribution
+ *  *   in the file called LICENSE.GPL.
+ *  *
+ *  *   Contact Information:
+ *  *   Intel Corporation
+ *  *
+ *  *   BSD LICENSE
+ *  *
+ *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *  *   All rights reserved.
+ *  *
+ *  *   Redistribution and use in source and binary forms, with or without
+ *  *   modification, are permitted provided that the following conditions
+ *  *   are met:
+ *  *
+ *  *     * Redistributions of source code must retain the above copyright
+ *  *       notice, this list of conditions and the following disclaimer.
+ *  *     * Redistributions in binary form must reproduce the above copyright
+ *  *       notice, this list of conditions and the following disclaimer in
+ *  *       the documentation and/or other materials provided with the
+ *  *       distribution.
+ *  *     * Neither the name of Intel Corporation nor the names of its
+ *  *       contributors may be used to endorse or promote products derived
+ *  *       from this software without specific prior written permission.
+ *  *
+ *  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *  *
+ *   */
+
+#ifndef _EVENTFD_LINK_H_
+#define _EVENTFD_LINK_H_
+
+/*
+ *	ioctl to copy an fd entry in calling process to an fd in a target process
+ */
+#define EVENTFD_COPY 1
+
+/*
+ *	arguements for the EVENTFD_COPY ioctl
+ */
+struct eventfd_copy {
+	// fd in the target pid
+    unsigned target_fd;
+	// fd in the calling pid
+    unsigned source_fd;
+	// pid of the target pid
+    pid_t target_pid;
+};
+#endif /* _EVENTFD_LINK_H_ */
diff --git a/lib/librte_vhost/libvirt/qemu-wrap.py b/lib/librte_vhost/libvirt/qemu-wrap.py
new file mode 100755
index 0000000..e2d68a0
--- /dev/null
+++ b/lib/librte_vhost/libvirt/qemu-wrap.py
@@ -0,0 +1,367 @@
+#!/usr/bin/python
+#/*
+# *   BSD LICENSE
+# *
+# *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+# *   All rights reserved.
+# *
+# *   Redistribution and use in source and binary forms, with or without
+# *   modification, are permitted provided that the following conditions
+# *   are met:
+# *
+# *     * Redistributions of source code must retain the above copyright
+# *       notice, this list of conditions and the following disclaimer.
+# *     * Redistributions in binary form must reproduce the above copyright
+# *       notice, this list of conditions and the following disclaimer in
+# *       the documentation and/or other materials provided with the
+# *       distribution.
+# *     * Neither the name of Intel Corporation nor the names of its
+# *       contributors may be used to endorse or promote products derived
+# *       from this software without specific prior written permission.
+# *
+# *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# */
+
+#####################################################################
+# This script is designed to modify the call to the QEMU emulator
+# to support userspace vhost when starting a guest machine through
+# libvirt with vhost enabled. The steps to enable this are as follows
+# and should be run as root:
+#
+# 1. Place this script in a libvirtd's binary search PATH ($PATH)
+#    A good location would be in the same directory that the QEMU
+#    binary is located
+#
+# 2. Ensure that the script has the same owner/group and file
+#    permissions as the QEMU binary
+#
+# 3. Update the VM xml file using "virsh edit VM.xml"
+#
+#    3.a) Set the VM to use the launch script
+#
+#    	Set the emulator path contained in the
+#		<emulator><emulator/> tags
+#
+#    	e.g replace <emulator>/usr/bin/qemu-kvm<emulator/>
+#        with    <emulator>/usr/bin/qemu-wrap.py<emulator/>
+#
+#	 3.b) Set the VM's device's to use vhost-net offload
+#
+#		<interface type="network">
+#       	<model type="virtio"/>
+#       	<driver name="vhost"/>
+#		<interface/>
+#
+# 4. Enable libvirt to access our userpace device file by adding it to
+#    controllers cgroup for libvirtd using the following steps
+#
+#   4.a) In /etc/libvirt/qemu.conf add/edit the following lines:
+#         1) cgroup_controllers = [ ... "devices", ... ]
+#		  2) clear_emulator_capabilities = 0
+#         3) user = "root"
+#         4) group = "root"
+#         5) cgroup_device_acl = [
+#                "/dev/null", "/dev/full", "/dev/zero",
+#                "/dev/random", "/dev/urandom",
+#                "/dev/ptmx", "/dev/kvm", "/dev/kqemu",
+#                "/dev/rtc", "/dev/hpet", "/dev/net/tun",
+#                "/dev/<devbase-name>-<index>",
+#            ]
+#
+#   4.b) Disable SELinux or set to permissive mode
+#
+#   4.c) Mount cgroup device controller
+#        "mkdir /dev/cgroup"
+#        "mount -t cgroup none /dev/cgroup -o devices"
+#
+#   4.d) Set hugetlbfs_mount variable - ( Optional )
+#        VMs using userspace vhost must use hugepage backed
+#        memory. This can be enabled in the libvirt XML
+#        config by adding a memory backing section to the
+#        XML config e.g.
+#             <memoryBacking>
+#             <hugepages/>
+#             </memoryBacking>
+#        This memory backing section should be added after the
+#        <memory> and <currentMemory> sections. This will add
+#        flags "-mem-prealloc -mem-path <path>" to the QEMU
+#        command line. The hugetlbfs_mount variable can be used
+#        to override the default <path> passed through by libvirt.
+#
+#        if "-mem-prealloc" or "-mem-path <path>" are not passed
+#        through and a vhost device is detected then these options will
+#        be automatically added by this script. This script will detect
+#        the system hugetlbfs mount point to be used for <path>. The
+#        default <path> for this script can be overidden by the
+#        hugetlbfs_dir variable in the configuration section of this script.
+#
+#
+#   4.e) Restart the libvirtd system process
+#        e.g. on Fedora "systemctl restart libvirtd.service"
+#
+#
+#   4.f) Edit the Configuration Parameters section of this script
+#        to point to the correct emulator location and set any
+#        addition options
+#
+# The script modifies the libvirtd Qemu call by modifying/adding
+# options based on the configuration parameters below.
+# NOTE:
+#     emul_path and us_vhost_path must be set
+#     All other parameters are optional
+#####################################################################
+
+
+#############################################
+# Configuration Parameters
+#############################################
+#Path to QEMU binary
+emul_path = "/usr/local/bin/qemu-system-x86_64"
+
+#Path to userspace vhost device file
+# This filename should match the --dev-basename --dev-index parameters of
+# the command used to launch the userspace vhost sample application e.g.
+# if the sample app lauch command is:
+#    ./build/vhost-switch ..... --dev-basename usvhost --dev-index 1
+# then this variable should be set to:
+#   us_vhost_path = "/dev/usvhost-1"
+us_vhost_path = "/dev/usvhost-1"
+
+#List of additional user defined emulation options. These options will
+#be added to all Qemu calls
+emul_opts_user = []
+
+#List of additional user defined emulation options for vhost only.
+#These options will only be added to vhost enabled guests
+emul_opts_user_vhost = []
+
+#For all VHOST enabled VMs, the VM memory is preallocated from hugetlbfs
+# Set this variable to one to enable this option for all VMs
+use_huge_all = 0
+
+#Instead of autodetecting, override the hugetlbfs directory by setting
+#this variable
+hugetlbfs_dir = ""
+
+#############################################
+
+
+#############################################
+# ****** Do Not Modify Below this Line ******
+#############################################
+
+import sys, os, subprocess
+
+
+#List of open userspace vhost file descriptors
+fd_list = []
+
+#additional virtio device flags when using userspace vhost
+vhost_flags = [ "csum=off",
+                "gso=off",
+                "guest_tso4=off",
+                "guest_tso6=off",
+                "guest_ecn=off"
+              ]
+
+
+#############################################
+# Find the system hugefile mount point.
+# Note:
+# if multiple hugetlbfs mount points exist
+# then the first one found will be used
+#############################################
+def find_huge_mount():
+
+    if (len(hugetlbfs_dir)):
+        return hugetlbfs_dir
+
+    huge_mount = ""
+
+    if (os.access("/proc/mounts", os.F_OK)):
+        f = open("/proc/mounts", "r")
+        line = f.readline()
+        while line:
+            line_split = line.split(" ")
+            if line_split[2] == 'hugetlbfs':
+                huge_mount = line_split[1]
+                break
+            line = f.readline()
+    else:
+        print "/proc/mounts not found"
+        exit (1)
+
+    f.close
+    if len(huge_mount) == 0:
+        print "Failed to find hugetlbfs mount point"
+        exit (1)
+
+    return huge_mount
+
+
+#############################################
+# Get a userspace Vhost file descriptor
+#############################################
+def get_vhost_fd():
+
+    if (os.access(us_vhost_path, os.F_OK)):
+        fd = os.open( us_vhost_path, os.O_RDWR)
+    else:
+        print ("US-Vhost file %s not found" %us_vhost_path)
+        exit (1)
+
+    return fd
+
+
+#############################################
+# Check for vhostfd. if found then replace
+# with our own vhost fd and append any vhost
+# flags onto the end
+#############################################
+def modify_netdev_arg(arg):
+	
+    global fd_list
+    vhost_in_use = 0
+    s = ''
+    new_opts = []
+    netdev_opts = arg.split(",")
+
+    for opt in netdev_opts:
+        #check if vhost is used
+        if "vhost" == opt[:5]:
+            vhost_in_use = 1
+        else:
+            new_opts.append(opt)
+
+    #if using vhost append vhost options
+    if vhost_in_use == 1:
+        #append vhost on option
+        new_opts.append('vhost=on')
+        #append vhostfd ption
+        new_fd = get_vhost_fd()
+        new_opts.append('vhostfd=' + str(new_fd))
+        fd_list.append(new_fd)
+
+    #concatenate all options
+    for opt in new_opts:
+        if len(s) > 0:
+			s+=','
+
+        s+=opt
+
+    return s	
+
+
+#############################################
+# Main
+#############################################
+def main():
+
+    global fd_list
+    global vhost_in_use
+    new_args = []
+    num_cmd_args = len(sys.argv)
+    emul_call = ''
+    mem_prealloc_set = 0
+    mem_path_set = 0
+    num = 0;
+
+    #parse the parameters
+    while (num < num_cmd_args):
+        arg = sys.argv[num]
+
+		#Check netdev +1 parameter for vhostfd
+        if arg == '-netdev':
+            num_vhost_devs = len(fd_list)
+            new_args.append(arg)
+
+            num+=1
+            arg = sys.argv[num]
+            mod_arg = modify_netdev_arg(arg)
+            new_args.append(mod_arg)
+
+            #append vhost flags if this is a vhost device
+            # and -device is the next arg
+            # i.e -device -opt1,-opt2,...,-opt3,%vhost
+            if (num_vhost_devs < len(fd_list)):
+                num+=1
+                arg = sys.argv[num]
+                if arg == '-device':
+                    new_args.append(arg)
+                    num+=1
+                    new_arg = sys.argv[num]
+                    for flag in vhost_flags:
+                        new_arg = ''.join([new_arg,',',flag])
+                    new_args.append(new_arg)
+                else:
+                    new_args.append(arg)
+        elif arg == '-mem-prealloc':
+            mem_prealloc_set = 1
+            new_args.append(arg)
+        elif arg == '-mem-path':
+            mem_path_set = 1
+            new_args.append(arg)
+
+        else:
+            new_args.append(arg)
+
+        num+=1
+
+    #Set Qemu binary location
+    emul_call+=emul_path
+    emul_call+=" "
+
+    #Add prealloc mem options if using vhost and not already added
+    if ((len(fd_list) > 0) and (mem_prealloc_set == 0)):
+        emul_call += "-mem-prealloc "
+
+    #Add mempath mem options if using vhost and not already added
+    if ((len(fd_list) > 0) and (mem_path_set == 0)):
+        #Detect and add hugetlbfs mount point
+        mp = find_huge_mount()
+        mp = "".join(["-mem-path ", mp])
+        emul_call += mp
+        emul_call += " "
+
+
+    #add user options
+    for opt in emul_opts_user:
+        emul_call += opt
+        emul_call += " "
+
+    #Add add user vhost only options
+    if len(fd_list) > 0:
+        for opt in emul_opts_user_vhost:
+            emul_call += opt
+            emul_call += " "
+
+    #Add updated libvirt options
+    iter_args = iter(new_args)
+    #skip 1st arg i.e. call to this script
+    next(iter_args)
+    for arg in iter_args:
+        emul_call+=str(arg)
+        emul_call+= " "
+
+    #Call QEMU
+    subprocess.call(emul_call, shell=True)
+
+
+    #Close usvhost files
+    for fd in fd_list:
+        os.close(fd)
+
+
+if __name__ == "__main__":
+    main()
+
diff --git a/lib/librte_vhost/main.c b/lib/librte_vhost/main.c
new file mode 100644
index 0000000..7d9e6a2
--- /dev/null
+++ b/lib/librte_vhost/main.c
@@ -0,0 +1,3722 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <arpa/inet.h>
+#include <getopt.h>
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <linux/virtio_net.h>
+#include <linux/virtio_ring.h>
+#include <signal.h>
+#include <stdint.h>
+#include <sys/eventfd.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+#include <rte_atomic.h>
+#include <rte_cycles.h>
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+#include <rte_malloc.h>
+
+#include "main.h"
+#include "virtio-net.h"
+#include "vhost-net-cdev.h"
+
+#define MAX_QUEUES 128
+
+/* the maximum number of external ports supported */
+#define MAX_SUP_PORTS 1
+
+/*
+ * Calculate the number of buffers needed per port
+ */
+#define NUM_MBUFS_PER_PORT ((MAX_QUEUES*RTE_TEST_RX_DESC_DEFAULT) +  		\
+							(num_switching_cores*MAX_PKT_BURST) +  			\
+							(num_switching_cores*RTE_TEST_TX_DESC_DEFAULT) +\
+							(num_switching_cores*MBUF_CACHE_SIZE))
+
+#define MBUF_CACHE_SIZE 128
+#define MBUF_SIZE (2048 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
+
+/*
+ * No frame data buffer allocated from host are required for zero copy
+ * implementation, guest will allocate the frame data buffer, and vhost
+ * directly use it.
+ */
+#define VIRTIO_DESCRIPTOR_LEN_ZCP 1518
+#define MBUF_SIZE_ZCP (VIRTIO_DESCRIPTOR_LEN_ZCP + sizeof(struct rte_mbuf) \
+	+ RTE_PKTMBUF_HEADROOM)
+#define MBUF_CACHE_SIZE_ZCP 0
+
+/*
+ * RX and TX Prefetch, Host, and Write-back threshold values should be
+ * carefully set for optimal performance. Consult the network
+ * controller's datasheet and supporting DPDK documentation for guidance
+ * on how these parameters should be set.
+ */
+#define RX_PTHRESH 8 /* Default values of RX prefetch threshold reg. */
+#define RX_HTHRESH 8 /* Default values of RX host threshold reg. */
+#define RX_WTHRESH 4 /* Default values of RX write-back threshold reg. */
+
+/*
+ * These default values are optimized for use with the Intel(R) 82599 10 GbE
+ * Controller and the DPDK ixgbe PMD. Consider using other values for other
+ * network controllers and/or network drivers.
+ */
+#define TX_PTHRESH 36 /* Default values of TX prefetch threshold reg. */
+#define TX_HTHRESH 0  /* Default values of TX host threshold reg. */
+#define TX_WTHRESH 0  /* Default values of TX write-back threshold reg. */
+
+#define MAX_PKT_BURST 32 		/* Max burst size for RX/TX */
+#define MAX_MRG_PKT_BURST 16 	/* Max burst for merge buffers. Set to 1 due to performance issue. */
+#define BURST_TX_DRAIN_US 100 	/* TX drain every ~100us */
+
+#define BURST_RX_WAIT_US 15 	/* Defines how long we wait between retries on RX */
+#define BURST_RX_RETRIES 4		/* Number of retries on RX. */
+
+#define JUMBO_FRAME_MAX_SIZE    0x2600
+
+/* State of virtio device. */
+#define DEVICE_MAC_LEARNING 0
+#define DEVICE_RX			1
+#define DEVICE_SAFE_REMOVE	2
+
+/* Config_core_flag status definitions. */
+#define REQUEST_DEV_REMOVAL 1
+#define ACK_DEV_REMOVAL 0
+
+/* Configurable number of RX/TX ring descriptors */
+#define RTE_TEST_RX_DESC_DEFAULT 1024
+#define RTE_TEST_TX_DESC_DEFAULT 512
+
+/*
+ * Need refine these 2 macros for legacy and DPDK based front end:
+ * Max vring avail descriptor/entries from guest - MAX_PKT_BURST
+ * And then adjust power 2.
+ */
+/*
+ * For legacy front end, 128 descriptors,
+ * half for virtio header, another half for mbuf.
+ */
+#define RTE_TEST_RX_DESC_DEFAULT_ZCP 32   /* legacy: 32, DPDK virt FE: 128. */
+#define RTE_TEST_TX_DESC_DEFAULT_ZCP 64   /* legacy: 64, DPDK virt FE: 64.  */
+
+/* Get first 4 bytes in mbuf headroom. */
+#define MBUF_HEADROOM_UINT32(mbuf) (*(uint32_t *)((uint8_t *)(mbuf) \
+		+ sizeof(struct rte_mbuf)))
+
+/* true if x is a power of 2 */
+#define POWEROF2(x) ((((x)-1) & (x)) == 0)
+
+#define INVALID_PORT_ID 0xFF
+
+/* Max number of devices. Limited by vmdq. */
+#define MAX_DEVICES 64
+
+/* Size of buffers used for snprintfs. */
+#define MAX_PRINT_BUFF 6072
+
+/* Maximum character device basename size. */
+#define MAX_BASENAME_SZ 10
+
+/* Maximum long option length for option parsing. */
+#define MAX_LONG_OPT_SZ 64
+
+/* Used to compare MAC addresses. */
+#define MAC_ADDR_CMP 0xFFFFFFFFFFFFULL
+
+/* Number of descriptors per cacheline. */
+#define DESC_PER_CACHELINE (CACHE_LINE_SIZE / sizeof(struct vring_desc))
+
+/* mask of enabled ports */
+static uint32_t enabled_port_mask = 0;
+
+/*Number of switching cores enabled*/
+static uint32_t num_switching_cores = 0;
+
+/* number of devices/queues to support*/
+static uint32_t num_queues = 0;
+uint32_t num_devices = 0;
+
+/*
+ * Enable zero copy, pkts buffer will directly dma to hw descriptor,
+ * disabled on default.
+ */
+static uint32_t zero_copy;
+
+/* number of descriptors to apply*/
+static uint32_t num_rx_descriptor = RTE_TEST_RX_DESC_DEFAULT_ZCP;
+static uint32_t num_tx_descriptor = RTE_TEST_TX_DESC_DEFAULT_ZCP;
+
+/* max ring descriptor, ixgbe, i40e, e1000 all are 4096. */
+#define MAX_RING_DESC 4096
+
+struct vpool {
+	struct rte_mempool *pool;
+	struct rte_ring *ring;
+	uint32_t buf_size;
+} vpool_array[MAX_QUEUES+MAX_QUEUES];
+
+/* Enable VM2VM communications. If this is disabled then the MAC address compare is skipped. */
+typedef enum {
+	VM2VM_DISABLED = 0,
+	VM2VM_SOFTWARE = 1,
+	VM2VM_HARDWARE = 2,
+	VM2VM_LAST
+} vm2vm_type;
+static vm2vm_type vm2vm_mode = VM2VM_SOFTWARE;
+
+/* The type of host physical address translated from guest physical address. */
+typedef enum {
+	PHYS_ADDR_CONTINUOUS = 0,
+	PHYS_ADDR_CROSS_SUBREG = 1,
+	PHYS_ADDR_INVALID = 2,
+	PHYS_ADDR_LAST
+} hpa_type;
+
+/* Enable stats. */
+static uint32_t enable_stats = 0;
+/* Enable retries on RX. */
+static uint32_t enable_retry = 1;
+/* Specify timeout (in useconds) between retries on RX. */
+static uint32_t burst_rx_delay_time = BURST_RX_WAIT_US;
+/* Specify the number of retries on RX. */
+static uint32_t burst_rx_retry_num = BURST_RX_RETRIES;
+
+/* Character device basename. Can be set by user. */
+static char dev_basename[MAX_BASENAME_SZ] = "vhost-net";
+
+/* Charater device index. Can be set by user. */
+static uint32_t dev_index = 0;
+
+/* This can be set by the user so it is made available here. */
+extern uint64_t VHOST_FEATURES;
+
+/* Default configuration for rx and tx thresholds etc. */
+static struct rte_eth_rxconf rx_conf_default = {
+	.rx_thresh = {
+		.pthresh = RX_PTHRESH,
+		.hthresh = RX_HTHRESH,
+		.wthresh = RX_WTHRESH,
+	},
+	.rx_drop_en = 1,
+};
+
+/*
+ * These default values are optimized for use with the Intel(R) 82599 10 GbE
+ * Controller and the DPDK ixgbe/igb PMD. Consider using other values for other
+ * network controllers and/or network drivers.
+ */
+static struct rte_eth_txconf tx_conf_default = {
+	.tx_thresh = {
+		.pthresh = TX_PTHRESH,
+		.hthresh = TX_HTHRESH,
+		.wthresh = TX_WTHRESH,
+	},
+	.tx_free_thresh = 0, /* Use PMD default values */
+	.tx_rs_thresh = 0, /* Use PMD default values */
+};
+
+/* empty vmdq configuration structure. Filled in programatically */
+static struct rte_eth_conf vmdq_conf_default = {
+	.rxmode = {
+		.mq_mode        = ETH_MQ_RX_VMDQ_ONLY,
+		.split_hdr_size = 0,
+		.header_split   = 0, /**< Header Split disabled */
+		.hw_ip_checksum = 0, /**< IP checksum offload disabled */
+		.hw_vlan_filter = 0, /**< VLAN filtering disabled */
+		/*
+		 * It is necessary for 1G NIC such as I350,
+		 * this fixes bug of ipv4 forwarding in guest can't
+		 * forward pakets from one virtio dev to another virtio dev.
+		 */
+		.hw_vlan_strip  = 1, /**< VLAN strip enabled. */
+		.jumbo_frame    = 0, /**< Jumbo Frame Support disabled */
+		.hw_strip_crc   = 0, /**< CRC stripped by hardware */
+	},
+
+	.txmode = {
+		.mq_mode = ETH_MQ_TX_NONE,
+	},
+	.rx_adv_conf = {
+		/*
+		 * should be overridden separately in code with
+		 * appropriate values
+		 */
+		.vmdq_rx_conf = {
+			.nb_queue_pools = ETH_8_POOLS,
+			.enable_default_pool = 0,
+			.default_pool = 0,
+			.nb_pool_maps = 0,
+			.pool_map = {{0, 0},},
+		},
+	},
+};
+
+static unsigned lcore_ids[RTE_MAX_LCORE];
+static uint8_t ports[RTE_MAX_ETHPORTS];
+static unsigned num_ports = 0; /**< The number of ports specified in command line */
+
+static const uint16_t external_pkt_default_vlan_tag = 2000;
+const uint16_t vlan_tags[] = {
+	1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007,
+	1008, 1009, 1010, 1011,	1012, 1013, 1014, 1015,
+	1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023,
+	1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031,
+	1032, 1033, 1034, 1035, 1036, 1037, 1038, 1039,
+	1040, 1041, 1042, 1043, 1044, 1045, 1046, 1047,
+	1048, 1049, 1050, 1051, 1052, 1053, 1054, 1055,
+	1056, 1057, 1058, 1059, 1060, 1061, 1062, 1063,
+};
+
+/* ethernet addresses of ports */
+static struct ether_addr vmdq_ports_eth_addr[RTE_MAX_ETHPORTS];
+
+/* heads for the main used and free linked lists for the data path. */
+static struct virtio_net_data_ll *ll_root_used = NULL;
+static struct virtio_net_data_ll *ll_root_free = NULL;
+
+/* Array of data core structures containing information on individual core linked lists. */
+static struct lcore_info lcore_info[RTE_MAX_LCORE];
+
+/* Used for queueing bursts of TX packets. */
+struct mbuf_table {
+	unsigned len;
+	unsigned txq_id;
+	struct rte_mbuf *m_table[MAX_PKT_BURST];
+};
+
+/* TX queue for each data core. */
+struct mbuf_table lcore_tx_queue[RTE_MAX_LCORE];
+
+/* TX queue fori each virtio device for zero copy. */
+struct mbuf_table tx_queue_zcp[MAX_QUEUES];
+
+/* Vlan header struct used to insert vlan tags on TX. */
+struct vlan_ethhdr {
+	unsigned char   h_dest[ETH_ALEN];
+	unsigned char   h_source[ETH_ALEN];
+	__be16          h_vlan_proto;
+	__be16          h_vlan_TCI;
+	__be16          h_vlan_encapsulated_proto;
+};
+
+/* IPv4 Header */
+struct ipv4_hdr {
+	uint8_t  version_ihl;		/**< version and header length */
+	uint8_t  type_of_service;	/**< type of service */
+	uint16_t total_length;		/**< length of packet */
+	uint16_t packet_id;		/**< packet ID */
+	uint16_t fragment_offset;	/**< fragmentation offset */
+	uint8_t  time_to_live;		/**< time to live */
+	uint8_t  next_proto_id;		/**< protocol ID */
+	uint16_t hdr_checksum;		/**< header checksum */
+	uint32_t src_addr;		/**< source address */
+	uint32_t dst_addr;		/**< destination address */
+} __attribute__((__packed__));
+
+/* Header lengths. */
+#define VLAN_HLEN       4
+#define VLAN_ETH_HLEN   18
+
+/* Per-device statistics struct */
+struct device_statistics {
+	uint64_t tx_total;
+	rte_atomic64_t rx_total_atomic;
+	uint64_t rx_total;
+	uint64_t tx;
+	rte_atomic64_t rx_atomic;
+	uint64_t rx;
+} __rte_cache_aligned;
+struct device_statistics dev_statistics[MAX_DEVICES];
+
+/*
+ * Builds up the correct configuration for VMDQ VLAN pool map
+ * according to the pool & queue limits.
+ */
+static inline int
+get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_devices)
+{
+	struct rte_eth_vmdq_rx_conf conf;
+	unsigned i;
+
+	memset(&conf, 0, sizeof(conf));
+	conf.nb_queue_pools = (enum rte_eth_nb_pools)num_devices;
+	conf.nb_pool_maps = num_devices;
+	conf.enable_loop_back =
+		vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back;
+
+	for (i = 0; i < conf.nb_pool_maps; i++) {
+		conf.pool_map[i].vlan_id = vlan_tags[ i ];
+		conf.pool_map[i].pools = (1UL << i);
+	}
+
+	(void)(rte_memcpy(eth_conf, &vmdq_conf_default, sizeof(*eth_conf)));
+	(void)(rte_memcpy(&eth_conf->rx_adv_conf.vmdq_rx_conf, &conf,
+		   sizeof(eth_conf->rx_adv_conf.vmdq_rx_conf)));
+	return 0;
+}
+
+/*
+ * Validate the device number according to the max pool number gotten form
+ * dev_info. If the device number is invalid, give the error message and
+ * return -1. Each device must have its own pool.
+ */
+static inline int
+validate_num_devices(uint32_t max_nb_devices)
+{
+	if (num_devices > max_nb_devices) {
+		RTE_LOG(ERR, VHOST_PORT, "invalid number of devices\n");
+		return -1;
+	}
+	return 0;
+}
+
+/*
+ * Initialises a given port using global settings and with the rx buffers
+ * coming from the mbuf_pool passed as parameter
+ */
+static inline int
+port_init(uint8_t port)
+{
+	struct rte_eth_dev_info dev_info;
+	struct rte_eth_conf port_conf;
+	uint16_t rx_rings, tx_rings;
+	uint16_t rx_ring_size, tx_ring_size;
+	int retval;
+	uint16_t q;
+
+	/* The max pool number from dev_info will be used to validate the pool number specified in cmd line */
+	rte_eth_dev_info_get (port, &dev_info);
+
+	/*configure the number of supported virtio devices based on VMDQ limits */
+	num_devices = dev_info.max_vmdq_pools;
+	num_queues = dev_info.max_rx_queues;
+
+	if (zero_copy) {
+		rx_ring_size = num_rx_descriptor;
+		tx_ring_size = num_tx_descriptor;
+		tx_rings = dev_info.max_tx_queues;
+	} else {
+		rx_ring_size = RTE_TEST_RX_DESC_DEFAULT;
+		tx_ring_size = RTE_TEST_TX_DESC_DEFAULT;
+		tx_rings = (uint16_t)rte_lcore_count();
+	}
+
+	retval = validate_num_devices(MAX_DEVICES);
+	if (retval < 0)
+		return retval;
+
+	/* Get port configuration. */
+	retval = get_eth_conf(&port_conf, num_devices);
+	if (retval < 0)
+		return retval;
+
+	if (port >= rte_eth_dev_count()) return -1;
+
+	rx_rings = (uint16_t)num_queues,
+	/* Configure ethernet device. */
+	retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
+	if (retval != 0)
+		return retval;
+
+	/* Setup the queues. */
+	for (q = 0; q < rx_rings; q ++) {
+		retval = rte_eth_rx_queue_setup(port, q, rx_ring_size,
+						rte_eth_dev_socket_id(port), &rx_conf_default,
+						vpool_array[q].pool);
+		if (retval < 0)
+			return retval;
+	}
+	for (q = 0; q < tx_rings; q ++) {
+		retval = rte_eth_tx_queue_setup(port, q, tx_ring_size,
+						rte_eth_dev_socket_id(port), &tx_conf_default);
+		if (retval < 0)
+			return retval;
+	}
+
+	/* Start the device. */
+	retval  = rte_eth_dev_start(port);
+	if (retval < 0) {
+		RTE_LOG(ERR, VHOST_DATA, "Failed to start the device.\n");
+		return retval;
+	}
+
+	rte_eth_macaddr_get(port, &vmdq_ports_eth_addr[port]);
+	RTE_LOG(INFO, VHOST_PORT, "Max virtio devices supported: %u\n", num_devices);
+	RTE_LOG(INFO, VHOST_PORT, "Port %u MAC: %02"PRIx8" %02"PRIx8" %02"PRIx8
+			" %02"PRIx8" %02"PRIx8" %02"PRIx8"\n",
+			(unsigned)port,
+			vmdq_ports_eth_addr[port].addr_bytes[0],
+			vmdq_ports_eth_addr[port].addr_bytes[1],
+			vmdq_ports_eth_addr[port].addr_bytes[2],
+			vmdq_ports_eth_addr[port].addr_bytes[3],
+			vmdq_ports_eth_addr[port].addr_bytes[4],
+			vmdq_ports_eth_addr[port].addr_bytes[5]);
+
+	return 0;
+}
+
+/*
+ * Set character device basename.
+ */
+static int
+us_vhost_parse_basename(const char *q_arg)
+{
+	/* parse number string */
+
+	if (strnlen(q_arg, MAX_BASENAME_SZ) > MAX_BASENAME_SZ)
+		return -1;
+	else
+		snprintf((char*)&dev_basename, MAX_BASENAME_SZ, "%s", q_arg);
+
+	return 0;
+}
+
+/*
+ * Parse the portmask provided at run time.
+ */
+static int
+parse_portmask(const char *portmask)
+{
+	char *end = NULL;
+	unsigned long pm;
+
+	errno = 0;
+
+	/* parse hexadecimal string */
+	pm = strtoul(portmask, &end, 16);
+	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
+		return -1;
+
+	if (pm == 0)
+		return -1;
+
+	return pm;
+
+}
+
+/*
+ * Parse num options at run time.
+ */
+static int
+parse_num_opt(const char *q_arg, uint32_t max_valid_value)
+{
+	char *end = NULL;
+	unsigned long num;
+
+	errno = 0;
+
+	/* parse unsigned int string */
+	num = strtoul(q_arg, &end, 10);
+	if ((q_arg[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
+		return -1;
+
+	if (num > max_valid_value)
+		return -1;
+
+	return num;
+
+}
+
+/*
+ * Display usage
+ */
+static void
+us_vhost_usage(const char *prgname)
+{
+	RTE_LOG(INFO, VHOST_CONFIG, "%s [EAL options] -- -p PORTMASK\n"
+	"		--vm2vm [0|1|2]\n"
+	"		--rx_retry [0|1] --mergeable [0|1] --stats [0-N]\n"
+	"		--dev-basename <name> --dev-index [0-N]\n"
+	"		--nb-devices ND\n"
+	"		-p PORTMASK: Set mask for ports to be used by application\n"
+	"		--vm2vm [0|1|2]: disable/software(default)/hardware vm2vm comms\n"
+	"		--rx-retry [0|1]: disable/enable(default) retries on rx. Enable retry if destintation queue is full\n"
+	"		--rx-retry-delay [0-N]: timeout(in usecond) between retries on RX. This makes effect only if retries on rx enabled\n"
+	"		--rx-retry-num [0-N]: the number of retries on rx. This makes effect only if retries on rx enabled\n"
+	"		--mergeable [0|1]: disable(default)/enable RX mergeable buffers\n"
+	"		--stats [0-N]: 0: Disable stats, N: Time in seconds to print stats\n"
+	"		--dev-basename: The basename to be used for the character device.\n"
+	"		--dev-index [0-N]: Defaults to zero if not used. Index is appended to basename.\n"
+	"		--zero-copy [0|1]: disable(default)/enable rx/tx "
+			"zero copy\n"
+	"		--rx-desc-num [0-N]: the number of descriptors on rx, "
+			"used only when zero copy is enabled.\n"
+	"		--tx-desc-num [0-N]: the number of descriptors on tx, "
+			"used only when zero copy is enabled.\n",
+	       prgname);
+}
+
+/*
+ * Parse the arguments given in the command line of the application.
+ */
+static int
+us_vhost_parse_args(int argc, char **argv)
+{
+	int opt, ret;
+	int option_index;
+	unsigned i;
+	const char *prgname = argv[0];
+	static struct option long_option[] = {
+		{"vm2vm", required_argument, NULL, 0},
+		{"rx-retry", required_argument, NULL, 0},
+		{"rx-retry-delay", required_argument, NULL, 0},
+		{"rx-retry-num", required_argument, NULL, 0},
+		{"mergeable", required_argument, NULL, 0},
+		{"stats", required_argument, NULL, 0},
+		{"dev-basename", required_argument, NULL, 0},
+		{"dev-index", required_argument, NULL, 0},
+		{"zero-copy", required_argument, NULL, 0},
+		{"rx-desc-num", required_argument, NULL, 0},
+		{"tx-desc-num", required_argument, NULL, 0},
+		{NULL, 0, 0, 0},
+	};
+
+	/* Parse command line */
+	while ((opt = getopt_long(argc, argv, "p:",long_option, &option_index)) != EOF) {
+		switch (opt) {
+		/* Portmask */
+		case 'p':
+			enabled_port_mask = parse_portmask(optarg);
+			if (enabled_port_mask == 0) {
+				RTE_LOG(INFO, VHOST_CONFIG, "Invalid portmask\n");
+				us_vhost_usage(prgname);
+				return -1;
+			}
+			break;
+
+		case 0:
+			/* Enable/disable vm2vm comms. */
+			if (!strncmp(long_option[option_index].name, "vm2vm",
+				MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, (VM2VM_LAST - 1));
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+						"Invalid argument for "
+						"vm2vm [0|1|2]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					vm2vm_mode = (vm2vm_type)ret;
+				}
+			}
+
+			/* Enable/disable retries on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					enable_retry = ret;
+				}
+			}
+
+			/* Specify the retries delay time (in useconds) on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry-delay", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-delay [0-N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					burst_rx_delay_time = ret;
+				}
+			}
+
+			/* Specify the retries number on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-num [0-N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					burst_rx_retry_num = ret;
+				}
+			}
+
+			/* Enable/disable RX mergeable buffers. */
+			if (!strncmp(long_option[option_index].name, "mergeable", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for mergeable [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					if (ret) {
+						vmdq_conf_default.rxmode.jumbo_frame = 1;
+						vmdq_conf_default.rxmode.max_rx_pkt_len
+							= JUMBO_FRAME_MAX_SIZE;
+						VHOST_FEATURES = (1ULL << VIRTIO_NET_F_MRG_RXBUF);
+					}
+				}
+			}
+
+			/* Enable/disable stats. */
+			if (!strncmp(long_option[option_index].name, "stats", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for stats [0..N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					enable_stats = ret;
+				}
+			}
+
+			/* Set character device basename. */
+			if (!strncmp(long_option[option_index].name, "dev-basename", MAX_LONG_OPT_SZ)) {
+				if (us_vhost_parse_basename(optarg) == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device basename (Max %d characters)\n", MAX_BASENAME_SZ);
+					us_vhost_usage(prgname);
+					return -1;
+				}
+			}
+
+			/* Set character device index. */
+			if (!strncmp(long_option[option_index].name, "dev-index", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device index [0..N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else
+					dev_index = ret;
+			}
+
+			/* Enable/disable rx/tx zero copy. */
+			if (!strncmp(long_option[option_index].name,
+				"zero-copy", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+						"Invalid argument"
+						" for zero-copy [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else
+					zero_copy = ret;
+
+				if (zero_copy) {
+#ifdef RTE_MBUF_SCATTER_GATHER
+					RTE_LOG(ERR, VHOST_CONFIG, "Before running "
+					"zero copy vhost APP, please "
+					"disable RTE_MBUF_SCATTER_GATHER\n"
+					"in config file and then rebuild DPDK "
+					"core lib!\n"
+					"Otherwise please disable zero copy "
+					"flag in command line!\n");
+					return -1;
+#endif
+				}
+			}
+
+			/* Specify the descriptor number on RX. */
+			if (!strncmp(long_option[option_index].name,
+				"rx-desc-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, MAX_RING_DESC);
+				if ((ret == -1) || (!POWEROF2(ret))) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+					"Invalid argument for rx-desc-num[0-N],"
+					"power of 2 required.\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					num_rx_descriptor = ret;
+				}
+			}
+
+			/* Specify the descriptor number on TX. */
+			if (!strncmp(long_option[option_index].name,
+				"tx-desc-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, MAX_RING_DESC);
+				if ((ret == -1) || (!POWEROF2(ret))) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+					"Invalid argument for tx-desc-num [0-N],"
+					"power of 2 required.\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					num_tx_descriptor = ret;
+				}
+			}
+
+			break;
+
+			/* Invalid option - print options. */
+		default:
+			us_vhost_usage(prgname);
+			return -1;
+		}
+	}
+
+	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
+		if (enabled_port_mask & (1 << i))
+			ports[num_ports++] = (uint8_t)i;
+	}
+
+	if ((num_ports ==  0) || (num_ports > MAX_SUP_PORTS)) {
+		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
+			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
+		return -1;
+	}
+
+	if ((zero_copy == 1) && (vm2vm_mode == VM2VM_SOFTWARE)) {
+		RTE_LOG(INFO, VHOST_PORT,
+			"Vhost zero copy doesn't support software vm2vm,"
+			"please specify 'vm2vm 2' to use hardware vm2vm.\n");
+		return -1;
+	}
+
+	if ((zero_copy == 1) && (vmdq_conf_default.rxmode.jumbo_frame == 1)) {
+		RTE_LOG(INFO, VHOST_PORT,
+			"Vhost zero copy doesn't support jumbo frame,"
+			"please specify '--mergeable 0' to disable the "
+			"mergeable feature.\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Update the global var NUM_PORTS and array PORTS according to system ports number
+ * and return valid ports number
+ */
+static unsigned check_ports_num(unsigned nb_ports)
+{
+	unsigned valid_num_ports = num_ports;
+	unsigned portid;
+
+	if (num_ports > nb_ports) {
+		RTE_LOG(INFO, VHOST_PORT, "\nSpecified port number(%u) exceeds total system port number(%u)\n",
+			num_ports, nb_ports);
+		num_ports = nb_ports;
+	}
+
+	for (portid = 0; portid < num_ports; portid ++) {
+		if (ports[portid] >= nb_ports) {
+			RTE_LOG(INFO, VHOST_PORT, "\nSpecified port ID(%u) exceeds max system port ID(%u)\n",
+				ports[portid], (nb_ports - 1));
+			ports[portid] = INVALID_PORT_ID;
+			valid_num_ports--;
+		}
+	}
+	return valid_num_ports;
+}
+
+/*
+ * Macro to print out packet contents. Wrapped in debug define so that the
+ * data path is not effected when debug is disabled.
+ */
+#ifdef DEBUG
+#define PRINT_PACKET(device, addr, size, header) do {																\
+	char *pkt_addr = (char*)(addr);																					\
+	unsigned int index;																								\
+	char packet[MAX_PRINT_BUFF];																					\
+																													\
+	if ((header))																									\
+		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size));				\
+	else																											\
+		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size));				\
+	for (index = 0; index < (size); index++) {																		\
+		snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF),	\
+			"%02hhx ", pkt_addr[index]);																			\
+	}																												\
+	snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF), "\n");	\
+																													\
+	LOG_DEBUG(VHOST_DATA, "%s", packet);																					\
+} while(0)
+#else
+#define PRINT_PACKET(device, addr, size, header) do{} while(0)
+#endif
+
+/*
+ * Function to convert guest physical addresses to vhost virtual addresses. This
+ * is used to convert virtio buffer addresses.
+ */
+static inline uint64_t __attribute__((always_inline))
+gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
+{
+	struct virtio_memory_regions *region;
+	uint32_t regionidx;
+	uint64_t vhost_va = 0;
+
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		region = &dev->mem->regions[regionidx];
+		if ((guest_pa >= region->guest_phys_address) &&
+			(guest_pa <= region->guest_phys_address_end)) {
+			vhost_va = region->address_offset + guest_pa;
+			break;
+		}
+	}
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| VVA %p\n",
+		dev->device_fh, (void*)(uintptr_t)guest_pa, (void*)(uintptr_t)vhost_va);
+
+	return vhost_va;
+}
+
+/*
+ * Function to convert guest physical addresses to vhost physical addresses.
+ * This is used to convert virtio buffer addresses.
+ */
+static inline uint64_t __attribute__((always_inline))
+gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
+	uint32_t buf_len, hpa_type *addr_type)
+{
+	struct virtio_memory_regions_hpa *region;
+	uint32_t regionidx;
+	uint64_t vhost_pa = 0;
+
+	*addr_type = PHYS_ADDR_INVALID;
+
+	for (regionidx = 0; regionidx < dev->mem->nregions_hpa; regionidx++) {
+		region = &dev->mem->regions_hpa[regionidx];
+		if ((guest_pa >= region->guest_phys_address) &&
+			(guest_pa <= region->guest_phys_address_end)) {
+			vhost_pa = region->host_phys_addr_offset + guest_pa;
+			if (likely((guest_pa + buf_len - 1)
+				<= region->guest_phys_address_end))
+				*addr_type = PHYS_ADDR_CONTINUOUS;
+			else
+				*addr_type = PHYS_ADDR_CROSS_SUBREG;
+			break;
+		}
+	}
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| HPA %p\n",
+		dev->device_fh, (void *)(uintptr_t)guest_pa,
+		(void *)(uintptr_t)vhost_pa);
+
+	return vhost_pa;
+}
+
+/*
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtio device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue. This function works when mergeable is disabled.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *buff;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
+	uint64_t buff_addr = 0;
+	uint64_t buff_hdr_addr = 0;
+	uint32_t head[MAX_PKT_BURST], packet_len = 0;
+	uint32_t head_idx, packet_success = 0;
+	uint32_t retry = 0;
+	uint16_t avail_idx, res_cur_idx;
+	uint16_t res_base_idx, res_end_idx;
+	uint16_t free_entries;
+	uint8_t success = 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
+
+	/* As many data cores may want access to available buffers, they need to be reserved. */
+	do {
+		res_base_idx = vq->last_used_idx_res;
+		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+
+		free_entries = (avail_idx - res_base_idx);
+		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
+		if (enable_retry && unlikely(count > free_entries)) {
+			for (retry = 0; retry < burst_rx_retry_num; retry++) {
+				rte_delay_us(burst_rx_delay_time);
+				avail_idx =
+					*((volatile uint16_t *)&vq->avail->idx);
+				free_entries = (avail_idx - res_base_idx);
+				if (count <= free_entries)
+					break;
+			}
+		}
+
+		/*check that we have enough buffers*/
+		if (unlikely(count > free_entries))
+			count = free_entries;
+
+		if (count == 0)
+			return 0;
+
+		res_end_idx = res_base_idx + count;
+		/* vq->last_used_idx_res is atomically updated. */
+		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
+									res_end_idx);
+	} while (unlikely(success == 0));
+	res_cur_idx = res_base_idx;
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
+
+	/* Prefetch available ring to retrieve indexes. */
+	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (head_idx = 0; head_idx < count; head_idx++)
+		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
+
+	/*Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+
+	while (res_cur_idx != res_end_idx) {
+		/* Get descriptor from available ring */
+		desc = &vq->desc[head[packet_success]];
+
+		buff = pkts[packet_success];
+
+		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void*)(uintptr_t)buff_addr);
+
+		/* Copy virtio_hdr to packet and increment buffer address */
+		buff_hdr_addr = buff_addr;
+		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+		/*
+		 * If the descriptors are chained the header and data are
+		 * placed in separate buffers.
+		 */
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc->len = vq->vhost_hlen;
+			desc = &vq->desc[desc->next];
+			/* Buffer address translation. */
+			buff_addr = gpa_to_vva(dev, desc->addr);
+			desc->len = rte_pktmbuf_data_len(buff);
+		} else {
+			buff_addr += vq->vhost_hlen;
+			desc->len = packet_len;
+		}
+
+		/* Update used ring with desc information */
+		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
+		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
+
+		/* Copy mbuf data to buffer */
+		rte_memcpy((void *)(uintptr_t)buff_addr,
+			(const void *)buff->pkt.data,
+			rte_pktmbuf_data_len(buff));
+		PRINT_PACKET(dev, (uintptr_t)buff_addr,
+			rte_pktmbuf_data_len(buff), 0);
+
+		res_cur_idx++;
+		packet_success++;
+
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
+			(const void *)&virtio_hdr, vq->vhost_hlen);
+
+		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+
+		if (res_cur_idx < res_end_idx) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success]]);
+		}
+	}
+
+	rte_compiler_barrier();
+
+	/* Wait until it's our turn to add our buffer to the used ring. */
+	while (unlikely(vq->last_used_idx != res_base_idx))
+		rte_pause();
+
+	*(volatile uint16_t *)&vq->used->idx += count;
+	vq->last_used_idx = res_end_idx;
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+	return count;
+}
+
+static inline uint32_t __attribute__((always_inline))
+copy_from_mbuf_to_vring(struct virtio_net *dev,
+	uint16_t res_base_idx, uint16_t res_end_idx,
+	struct rte_mbuf *pkt)
+{
+	uint32_t vec_idx = 0;
+	uint32_t entry_success = 0;
+	struct vhost_virtqueue *vq;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {
+		{0, 0, 0, 0, 0, 0}, 0};
+	uint16_t cur_idx = res_base_idx;
+	uint64_t vb_addr = 0;
+	uint64_t vb_hdr_addr = 0;
+	uint32_t seg_offset = 0;
+	uint32_t vb_offset = 0;
+	uint32_t seg_avail;
+	uint32_t vb_avail;
+	uint32_t cpy_len, entry_len;
+
+	if (pkt == NULL)
+		return 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| "
+		"End Index %d\n",
+		dev->device_fh, cur_idx, res_end_idx);
+
+	/*
+	 * Convert from gpa to vva
+	 * (guest physical addr -> vhost virtual addr)
+	 */
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	vb_addr =
+		gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
+	vb_hdr_addr = vb_addr;
+
+	/* Prefetch buffer address. */
+	rte_prefetch0((void *)(uintptr_t)vb_addr);
+
+	virtio_hdr.num_buffers = res_end_idx - res_base_idx;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n",
+		dev->device_fh, virtio_hdr.num_buffers);
+
+	rte_memcpy((void *)(uintptr_t)vb_hdr_addr,
+		(const void *)&virtio_hdr, vq->vhost_hlen);
+
+	PRINT_PACKET(dev, (uintptr_t)vb_hdr_addr, vq->vhost_hlen, 1);
+
+	seg_avail = rte_pktmbuf_data_len(pkt);
+	vb_offset = vq->vhost_hlen;
+	vb_avail =
+		vq->buf_vec[vec_idx].buf_len - vq->vhost_hlen;
+
+	entry_len = vq->vhost_hlen;
+
+	if (vb_avail == 0) {
+		uint32_t desc_idx =
+			vq->buf_vec[vec_idx].desc_idx;
+		vq->desc[desc_idx].len = vq->vhost_hlen;
+
+		if ((vq->desc[desc_idx].flags
+			& VRING_DESC_F_NEXT) == 0) {
+			/* Update used ring with desc information */
+			vq->used->ring[cur_idx & (vq->size - 1)].id
+				= vq->buf_vec[vec_idx].desc_idx;
+			vq->used->ring[cur_idx & (vq->size - 1)].len
+				= entry_len;
+
+			entry_len = 0;
+			cur_idx++;
+			entry_success++;
+		}
+
+		vec_idx++;
+		vb_addr =
+			gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
+
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)vb_addr);
+		vb_offset = 0;
+		vb_avail = vq->buf_vec[vec_idx].buf_len;
+	}
+
+	cpy_len = RTE_MIN(vb_avail, seg_avail);
+
+	while (cpy_len > 0) {
+		/* Copy mbuf data to vring buffer */
+		rte_memcpy((void *)(uintptr_t)(vb_addr + vb_offset),
+			(const void *)(rte_pktmbuf_mtod(pkt, char*) + seg_offset),
+			cpy_len);
+
+		PRINT_PACKET(dev,
+			(uintptr_t)(vb_addr + vb_offset),
+			cpy_len, 0);
+
+		seg_offset += cpy_len;
+		vb_offset += cpy_len;
+		seg_avail -= cpy_len;
+		vb_avail -= cpy_len;
+		entry_len += cpy_len;
+
+		if (seg_avail != 0) {
+			/*
+			 * The virtio buffer in this vring
+			 * entry reach to its end.
+			 * But the segment doesn't complete.
+			 */
+			if ((vq->desc[vq->buf_vec[vec_idx].desc_idx].flags &
+				VRING_DESC_F_NEXT) == 0) {
+				/* Update used ring with desc information */
+				vq->used->ring[cur_idx & (vq->size - 1)].id
+					= vq->buf_vec[vec_idx].desc_idx;
+				vq->used->ring[cur_idx & (vq->size - 1)].len
+					= entry_len;
+				entry_len = 0;
+				cur_idx++;
+				entry_success++;
+			}
+
+			vec_idx++;
+			vb_addr = gpa_to_vva(dev,
+				vq->buf_vec[vec_idx].buf_addr);
+			vb_offset = 0;
+			vb_avail = vq->buf_vec[vec_idx].buf_len;
+			cpy_len = RTE_MIN(vb_avail, seg_avail);
+		} else {
+			/*
+			 * This current segment complete, need continue to
+			 * check if the whole packet complete or not.
+			 */
+			pkt = pkt->pkt.next;
+			if (pkt != NULL) {
+				/*
+				 * There are more segments.
+				 */
+				if (vb_avail == 0) {
+					/*
+					 * This current buffer from vring is
+					 * used up, need fetch next buffer
+					 * from buf_vec.
+					 */
+					uint32_t desc_idx =
+						vq->buf_vec[vec_idx].desc_idx;
+					vq->desc[desc_idx].len = vb_offset;
+
+					if ((vq->desc[desc_idx].flags &
+						VRING_DESC_F_NEXT) == 0) {
+						uint16_t wrapped_idx =
+							cur_idx & (vq->size - 1);
+						/*
+						 * Update used ring with the
+						 * descriptor information
+						 */
+						vq->used->ring[wrapped_idx].id
+							= desc_idx;
+						vq->used->ring[wrapped_idx].len
+							= entry_len;
+						entry_success++;
+						entry_len = 0;
+						cur_idx++;
+					}
+
+					/* Get next buffer from buf_vec. */
+					vec_idx++;
+					vb_addr = gpa_to_vva(dev,
+						vq->buf_vec[vec_idx].buf_addr);
+					vb_avail =
+						vq->buf_vec[vec_idx].buf_len;
+					vb_offset = 0;
+				}
+
+				seg_offset = 0;
+				seg_avail = rte_pktmbuf_data_len(pkt);
+				cpy_len = RTE_MIN(vb_avail, seg_avail);
+			} else {
+				/*
+				 * This whole packet completes.
+				 */
+				uint32_t desc_idx =
+					vq->buf_vec[vec_idx].desc_idx;
+				vq->desc[desc_idx].len = vb_offset;
+
+				while (vq->desc[desc_idx].flags &
+					VRING_DESC_F_NEXT) {
+					desc_idx = vq->desc[desc_idx].next;
+					 vq->desc[desc_idx].len = 0;
+				}
+
+				/* Update used ring with desc information */
+				vq->used->ring[cur_idx & (vq->size - 1)].id
+					= vq->buf_vec[vec_idx].desc_idx;
+				vq->used->ring[cur_idx & (vq->size - 1)].len
+					= entry_len;
+				entry_len = 0;
+				cur_idx++;
+				entry_success++;
+				seg_avail = 0;
+				cpy_len = RTE_MIN(vb_avail, seg_avail);
+			}
+		}
+	}
+
+	return entry_success;
+}
+
+/*
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtio device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue. This function works for mergeable RX.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_merge_rx(struct virtio_net *dev, struct rte_mbuf **pkts,
+	uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	uint32_t pkt_idx = 0, entry_success = 0;
+	uint32_t retry = 0;
+	uint16_t avail_idx, res_cur_idx;
+	uint16_t res_base_idx, res_end_idx;
+	uint8_t success = 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_rx()\n",
+		dev->device_fh);
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
+
+	if (count == 0)
+		return 0;
+
+	for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
+		uint32_t secure_len = 0;
+		uint16_t need_cnt;
+		uint32_t vec_idx = 0;
+		uint32_t pkt_len = pkts[pkt_idx]->pkt.pkt_len + vq->vhost_hlen;
+		uint16_t i, id;
+
+		do {
+			/*
+			 * As many data cores may want access to available
+			 * buffers, they need to be reserved.
+			 */
+			res_base_idx = vq->last_used_idx_res;
+			res_cur_idx = res_base_idx;
+
+			do {
+				avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+				if (unlikely(res_cur_idx == avail_idx)) {
+					/*
+					 * If retry is enabled and the queue is
+					 * full then we wait and retry to avoid
+					 * packet loss.
+					 */
+					if (enable_retry) {
+						uint8_t cont = 0;
+						for (retry = 0; retry < burst_rx_retry_num; retry++) {
+							rte_delay_us(burst_rx_delay_time);
+							avail_idx =
+								*((volatile uint16_t *)&vq->avail->idx);
+							if (likely(res_cur_idx != avail_idx)) {
+								cont = 1;
+								break;
+							}
+						}
+						if (cont == 1)
+							continue;
+					}
+
+					LOG_DEBUG(VHOST_DATA,
+						"(%"PRIu64") Failed "
+						"to get enough desc from "
+						"vring\n",
+						dev->device_fh);
+					return pkt_idx;
+				} else {
+					uint16_t wrapped_idx =
+						(res_cur_idx) & (vq->size - 1);
+					uint32_t idx =
+						vq->avail->ring[wrapped_idx];
+					uint8_t next_desc;
+
+					do {
+						next_desc = 0;
+						secure_len += vq->desc[idx].len;
+						if (vq->desc[idx].flags &
+							VRING_DESC_F_NEXT) {
+							idx = vq->desc[idx].next;
+							next_desc = 1;
+						}
+					} while (next_desc);
+
+					res_cur_idx++;
+				}
+			} while (pkt_len > secure_len);
+
+			/* vq->last_used_idx_res is atomically updated. */
+			success = rte_atomic16_cmpset(&vq->last_used_idx_res,
+							res_base_idx,
+							res_cur_idx);
+		} while (success == 0);
+
+		id = res_base_idx;
+		need_cnt = res_cur_idx - res_base_idx;
+
+		for (i = 0; i < need_cnt; i++, id++) {
+			uint16_t wrapped_idx = id & (vq->size - 1);
+			uint32_t idx = vq->avail->ring[wrapped_idx];
+			uint8_t next_desc;
+			do {
+				next_desc = 0;
+				vq->buf_vec[vec_idx].buf_addr =
+					vq->desc[idx].addr;
+				vq->buf_vec[vec_idx].buf_len =
+					vq->desc[idx].len;
+				vq->buf_vec[vec_idx].desc_idx = idx;
+				vec_idx++;
+
+				if (vq->desc[idx].flags & VRING_DESC_F_NEXT) {
+					idx = vq->desc[idx].next;
+					next_desc = 1;
+				}
+			} while (next_desc);
+		}
+
+		res_end_idx = res_cur_idx;
+
+		entry_success = copy_from_mbuf_to_vring(dev, res_base_idx,
+			res_end_idx, pkts[pkt_idx]);
+
+		rte_compiler_barrier();
+
+		/*
+		 * Wait until it's our turn to add our buffer
+		 * to the used ring.
+		 */
+		while (unlikely(vq->last_used_idx != res_base_idx))
+			rte_pause();
+
+		*(volatile uint16_t *)&vq->used->idx += entry_success;
+		vq->last_used_idx = res_end_idx;
+
+		/* Kick the guest if necessary. */
+		if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+			eventfd_write((int)vq->kickfd, 1);
+	}
+
+	return count;
+}
+
+/*
+ * Compares a packet destination MAC address to a device MAC address.
+ */
+static inline int __attribute__((always_inline))
+ether_addr_cmp(struct ether_addr *ea, struct ether_addr *eb)
+{
+	return (((*(uint64_t *)ea ^ *(uint64_t *)eb) & MAC_ADDR_CMP) == 0);
+}
+
+/*
+ * This function learns the MAC address of the device and registers this along with a
+ * vlan tag to a VMDQ.
+ */
+static int
+link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
+{
+	struct ether_hdr *pkt_hdr;
+	struct virtio_net_data_ll *dev_ll;
+	int i, ret;
+
+	/* Learn MAC address of guest device from packet */
+	pkt_hdr = (struct ether_hdr *)m->pkt.data;
+
+	dev_ll = ll_root_used;
+
+	while (dev_ll != NULL) {
+		if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->dev->mac_address)) {
+			RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") WARNING: This device is using an existing MAC address and has not been registered.\n", dev->device_fh);
+			return -1;
+		}
+		dev_ll = dev_ll->next;
+	}
+
+	for (i = 0; i < ETHER_ADDR_LEN; i++)
+		dev->mac_address.addr_bytes[i] = pkt_hdr->s_addr.addr_bytes[i];
+
+	/* vlan_tag currently uses the device_id. */
+	dev->vlan_tag = vlan_tags[dev->device_fh];
+
+	/* Print out VMDQ registration info. */
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") MAC_ADDRESS %02x:%02x:%02x:%02x:%02x:%02x and VLAN_TAG %d registered\n",
+		dev->device_fh,
+		dev->mac_address.addr_bytes[0], dev->mac_address.addr_bytes[1],
+		dev->mac_address.addr_bytes[2], dev->mac_address.addr_bytes[3],
+		dev->mac_address.addr_bytes[4], dev->mac_address.addr_bytes[5],
+		dev->vlan_tag);
+
+	/* Register the MAC address. */
+	ret = rte_eth_dev_mac_addr_add(ports[0], &dev->mac_address, (uint32_t)dev->device_fh);
+	if (ret)
+		RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Failed to add device MAC address to VMDQ\n",
+					dev->device_fh);
+
+	/* Enable stripping of the vlan tag as we handle routing. */
+	rte_eth_dev_set_vlan_strip_on_queue(ports[0], (uint16_t)dev->vmdq_rx_q, 1);
+
+	/* Set device as ready for RX. */
+	dev->ready = DEVICE_RX;
+
+	return 0;
+}
+
+/*
+ * Removes MAC address and vlan tag from VMDQ. Ensures that nothing is adding buffers to the RX
+ * queue before disabling RX on the device.
+ */
+static inline void
+unlink_vmdq(struct virtio_net *dev)
+{
+	unsigned i = 0;
+	unsigned rx_count;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+
+	if (dev->ready == DEVICE_RX) {
+		/*clear MAC and VLAN settings*/
+		rte_eth_dev_mac_addr_remove(ports[0], &dev->mac_address);
+		for (i = 0; i < 6; i++)
+			dev->mac_address.addr_bytes[i] = 0;
+
+		dev->vlan_tag = 0;
+
+		/*Clear out the receive buffers*/
+		rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+
+		while (rx_count) {
+			for (i = 0; i < rx_count; i++)
+				rte_pktmbuf_free(pkts_burst[i]);
+
+			rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+		}
+
+		dev->ready = DEVICE_MAC_LEARNING;
+	}
+}
+
+/*
+ * Check if the packet destination MAC address is for a local device. If so then put
+ * the packet on that devices RX queue. If not then return.
+ */
+static inline unsigned __attribute__((always_inline))
+virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
+{
+	struct virtio_net_data_ll *dev_ll;
+	struct ether_hdr *pkt_hdr;
+	uint64_t ret = 0;
+
+	pkt_hdr = (struct ether_hdr *)m->pkt.data;
+
+	/*get the used devices list*/
+	dev_ll = ll_root_used;
+
+	while (dev_ll != NULL) {
+		if ((dev_ll->dev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
+				          &dev_ll->dev->mac_address)) {
+
+			/* Drop the packet if the TX packet is destined for the TX device. */
+			if (dev_ll->dev->device_fh == dev->device_fh) {
+				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
+							dev_ll->dev->device_fh);
+				return 0;
+			}
+
+
+			LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", dev_ll->dev->device_fh);
+
+			if (dev_ll->dev->remove) {
+				/*drop the packet if the device is marked for removal*/
+				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", dev_ll->dev->device_fh);
+			} else {
+				uint32_t mergeable =
+					dev_ll->dev->features &
+					(1 << VIRTIO_NET_F_MRG_RXBUF);
+
+				/*send the packet to the local virtio device*/
+				if (likely(mergeable == 0))
+					ret = virtio_dev_rx(dev_ll->dev, &m, 1);
+				else
+					ret = virtio_dev_merge_rx(dev_ll->dev,
+						&m, 1);
+
+				if (enable_stats) {
+					rte_atomic64_add(
+					&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
+					1);
+					rte_atomic64_add(
+					&dev_statistics[dev_ll->dev->device_fh].rx_atomic,
+					ret);
+					dev_statistics[dev->device_fh].tx_total++;
+					dev_statistics[dev->device_fh].tx += ret;
+				}
+			}
+
+			return 0;
+		}
+		dev_ll = dev_ll->next;
+	}
+
+	return -1;
+}
+
+/*
+ * This function routes the TX packet to the correct interface. This may be a local device
+ * or the physical port.
+ */
+static inline void __attribute__((always_inline))
+virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *mbuf_pool, uint16_t vlan_tag)
+{
+	struct mbuf_table *tx_q;
+	struct vlan_ethhdr *vlan_hdr;
+	struct rte_mbuf **m_table;
+	struct rte_mbuf *mbuf, *prev;
+	unsigned len, ret, offset = 0;
+	const uint16_t lcore_id = rte_lcore_id();
+	struct virtio_net_data_ll *dev_ll = ll_root_used;
+	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
+
+	/*check if destination is local VM*/
+	if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(dev, m) == 0))
+		return;
+
+	if (vm2vm_mode == VM2VM_HARDWARE) {
+		while (dev_ll != NULL) {
+			if ((dev_ll->dev->ready == DEVICE_RX)
+				&& ether_addr_cmp(&(pkt_hdr->d_addr),
+				&dev_ll->dev->mac_address)) {
+				/*
+				 * Drop the packet if the TX packet is
+				 * destined for the TX device.
+				 */
+				if (dev_ll->dev->device_fh == dev->device_fh) {
+					LOG_DEBUG(VHOST_DATA,
+					"(%"PRIu64") TX: Source and destination"
+					" MAC addresses are the same. Dropping "
+					"packet.\n",
+					dev_ll->dev->device_fh);
+					return;
+				}
+				offset = 4;
+				vlan_tag =
+				(uint16_t)
+				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
+
+				LOG_DEBUG(VHOST_DATA,
+				"(%"PRIu64") TX: pkt to local VM device id:"
+				"(%"PRIu64") vlan tag: %d.\n",
+				dev->device_fh, dev_ll->dev->device_fh,
+				vlan_tag);
+
+				break;
+			}
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is external\n", dev->device_fh);
+
+	/*Add packet to the port tx queue*/
+	tx_q = &lcore_tx_queue[lcore_id];
+	len = tx_q->len;
+
+	/* Allocate an mbuf and populate the structure. */
+	mbuf = rte_pktmbuf_alloc(mbuf_pool);
+	if (unlikely(mbuf == NULL)) {
+		RTE_LOG(ERR, VHOST_DATA,
+			"Failed to allocate memory for mbuf.\n");
+		return;
+	}
+
+	mbuf->pkt.data_len = m->pkt.data_len + VLAN_HLEN + offset;
+	mbuf->pkt.pkt_len = m->pkt.pkt_len + VLAN_HLEN + offset;
+	mbuf->pkt.nb_segs = m->pkt.nb_segs;
+
+	/* Copy ethernet header to mbuf. */
+	rte_memcpy((void*)mbuf->pkt.data, (const void*)m->pkt.data, ETH_HLEN);
+
+
+	/* Setup vlan header. Bytes need to be re-ordered for network with htons()*/
+	vlan_hdr = (struct vlan_ethhdr *) mbuf->pkt.data;
+	vlan_hdr->h_vlan_encapsulated_proto = vlan_hdr->h_vlan_proto;
+	vlan_hdr->h_vlan_proto = htons(ETH_P_8021Q);
+	vlan_hdr->h_vlan_TCI = htons(vlan_tag);
+
+	/* Copy the remaining packet contents to the mbuf. */
+	rte_memcpy((void*) ((uint8_t*)mbuf->pkt.data + VLAN_ETH_HLEN),
+		(const void*) ((uint8_t*)m->pkt.data + ETH_HLEN), (m->pkt.data_len - ETH_HLEN));
+
+	/* Copy the remaining segments for the whole packet. */
+	prev = mbuf;
+	while (m->pkt.next) {
+		/* Allocate an mbuf and populate the structure. */
+		struct rte_mbuf *next_mbuf = rte_pktmbuf_alloc(mbuf_pool);
+		if (unlikely(next_mbuf == NULL)) {
+			rte_pktmbuf_free(mbuf);
+			RTE_LOG(ERR, VHOST_DATA,
+				"Failed to allocate memory for mbuf.\n");
+			return;
+		}
+
+		m = m->pkt.next;
+		prev->pkt.next = next_mbuf;
+		prev = next_mbuf;
+		next_mbuf->pkt.data_len = m->pkt.data_len;
+
+		/* Copy data to next mbuf. */
+		rte_memcpy(rte_pktmbuf_mtod(next_mbuf, void *),
+			rte_pktmbuf_mtod(m, const void *), m->pkt.data_len);
+	}
+
+	tx_q->m_table[len] = mbuf;
+	len++;
+	if (enable_stats) {
+		dev_statistics[dev->device_fh].tx_total++;
+		dev_statistics[dev->device_fh].tx++;
+	}
+
+	if (unlikely(len == MAX_PKT_BURST)) {
+		m_table = (struct rte_mbuf **)tx_q->m_table;
+		ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
+		/* Free any buffers not handled by TX and update the port stats. */
+		if (unlikely(ret < len)) {
+			do {
+				rte_pktmbuf_free(m_table[ret]);
+			} while (++ret < len);
+		}
+
+		len = 0;
+	}
+
+	tx_q->len = len;
+	return;
+}
+
+static inline void __attribute__((always_inline))
+virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
+{
+	struct rte_mbuf m;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t buff_addr = 0;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t used_idx;
+	uint32_t i;
+	uint16_t free_entries, packet_success = 0;
+	uint16_t avail_idx;
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	/*get the number of free entries in the ring*/
+	free_entries = (avail_idx - vq->last_used_idx);
+
+	/* Limit to MAX_PKT_BURST. */
+	if (free_entries > MAX_PKT_BURST)
+		free_entries = MAX_PKT_BURST;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (packet_success < free_entries) {
+		desc = &vq->desc[head[packet_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void*)(uintptr_t)buff_addr);
+
+		used_idx = vq->last_used_idx & (vq->size - 1);
+
+		if (packet_success < (free_entries - 1)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success+1]]);
+			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
+		}
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = head[packet_success];
+		vq->used->ring[used_idx].len = 0;
+
+		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
+		m.pkt.data_len = desc->len;
+		m.pkt.pkt_len = desc->len;
+		m.pkt.data = (void*)(uintptr_t)buff_addr;
+
+		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+
+		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
+		if (dev->ready == DEVICE_MAC_LEARNING) {
+			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
+				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
+				packet_success += free_entries;
+				vq->last_used_idx += packet_success;
+				break;
+			}
+		}
+		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
+
+		vq->last_used_idx++;
+		packet_success++;
+	}
+
+	rte_compiler_barrier();
+	vq->used->idx += packet_success;
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+}
+
+/* This function works for TX packets with mergeable feature enabled. */
+static inline void __attribute__((always_inline))
+virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool)
+{
+	struct rte_mbuf *m, *prev;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t vb_addr = 0;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t used_idx;
+	uint32_t i;
+	uint16_t free_entries, entry_success = 0;
+	uint16_t avail_idx;
+	uint32_t buf_size = MBUF_SIZE - (sizeof(struct rte_mbuf)
+			+ RTE_PKTMBUF_HEADROOM);
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_tx()\n",
+		dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	/*get the number of free entries in the ring*/
+	free_entries = (avail_idx - vq->last_used_idx);
+
+	/* Limit to MAX_PKT_BURST. */
+	free_entries = RTE_MIN(free_entries, MAX_PKT_BURST);
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
+		dev->device_fh, free_entries);
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[entry_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (entry_success < free_entries) {
+		uint32_t vb_avail, vb_offset;
+		uint32_t seg_avail, seg_offset;
+		uint32_t cpy_len;
+		uint32_t seg_num = 0;
+		struct rte_mbuf *cur;
+		uint8_t alloc_err = 0;
+
+		desc = &vq->desc[head[entry_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		vb_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)vb_addr);
+
+		used_idx = vq->last_used_idx & (vq->size - 1);
+
+		if (entry_success < (free_entries - 1)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[entry_success+1]]);
+			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
+		}
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = head[entry_success];
+		vq->used->ring[used_idx].len = 0;
+
+		vb_offset = 0;
+		vb_avail = desc->len;
+		seg_offset = 0;
+		seg_avail = buf_size;
+		cpy_len = RTE_MIN(vb_avail, seg_avail);
+
+		PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
+
+		/* Allocate an mbuf and populate the structure. */
+		m = rte_pktmbuf_alloc(mbuf_pool);
+		if (unlikely(m == NULL)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"Failed to allocate memory for mbuf.\n");
+			return;
+		}
+
+		seg_num++;
+		cur = m;
+		prev = m;
+		while (cpy_len != 0) {
+			rte_memcpy((void *)(rte_pktmbuf_mtod(cur, char *) + seg_offset),
+				(void *)((uintptr_t)(vb_addr + vb_offset)),
+				cpy_len);
+
+			seg_offset += cpy_len;
+			vb_offset += cpy_len;
+			vb_avail -= cpy_len;
+			seg_avail -= cpy_len;
+
+			if (vb_avail != 0) {
+				/*
+				 * The segment reachs to its end,
+				 * while the virtio buffer in TX vring has
+				 * more data to be copied.
+				 */
+				cur->pkt.data_len = seg_offset;
+				m->pkt.pkt_len += seg_offset;
+				/* Allocate mbuf and populate the structure. */
+				cur = rte_pktmbuf_alloc(mbuf_pool);
+				if (unlikely(cur == NULL)) {
+					RTE_LOG(ERR, VHOST_DATA, "Failed to "
+						"allocate memory for mbuf.\n");
+					rte_pktmbuf_free(m);
+					alloc_err = 1;
+					break;
+				}
+
+				seg_num++;
+				prev->pkt.next = cur;
+				prev = cur;
+				seg_offset = 0;
+				seg_avail = buf_size;
+			} else {
+				if (desc->flags & VRING_DESC_F_NEXT) {
+					/*
+					 * There are more virtio buffers in
+					 * same vring entry need to be copied.
+					 */
+					if (seg_avail == 0) {
+						/*
+						 * The current segment hasn't
+						 * room to accomodate more
+						 * data.
+						 */
+						cur->pkt.data_len = seg_offset;
+						m->pkt.pkt_len += seg_offset;
+						/*
+						 * Allocate an mbuf and
+						 * populate the structure.
+						 */
+						cur = rte_pktmbuf_alloc(mbuf_pool);
+						if (unlikely(cur == NULL)) {
+							RTE_LOG(ERR,
+								VHOST_DATA,
+								"Failed to "
+								"allocate memory "
+								"for mbuf\n");
+							rte_pktmbuf_free(m);
+							alloc_err = 1;
+							break;
+						}
+						seg_num++;
+						prev->pkt.next = cur;
+						prev = cur;
+						seg_offset = 0;
+						seg_avail = buf_size;
+					}
+
+					desc = &vq->desc[desc->next];
+
+					/* Buffer address translation. */
+					vb_addr = gpa_to_vva(dev, desc->addr);
+					/* Prefetch buffer address. */
+					rte_prefetch0((void *)(uintptr_t)vb_addr);
+					vb_offset = 0;
+					vb_avail = desc->len;
+
+					PRINT_PACKET(dev, (uintptr_t)vb_addr,
+						desc->len, 0);
+				} else {
+					/* The whole packet completes. */
+					cur->pkt.data_len = seg_offset;
+					m->pkt.pkt_len += seg_offset;
+					vb_avail = 0;
+				}
+			}
+
+			cpy_len = RTE_MIN(vb_avail, seg_avail);
+		}
+
+		if (unlikely(alloc_err == 1))
+			break;
+
+		m->pkt.nb_segs = seg_num;
+
+		/*
+		 * If this is the first received packet we need to learn
+		 * the MAC and setup VMDQ
+		 */
+		if (dev->ready == DEVICE_MAC_LEARNING) {
+			if (dev->remove || (link_vmdq(dev, m) == -1)) {
+				/*
+				 * Discard frame if device is scheduled for
+				 * removal or a duplicate MAC address is found.
+				 */
+				entry_success = free_entries;
+				vq->last_used_idx += entry_success;
+				rte_pktmbuf_free(m);
+				break;
+			}
+		}
+
+		virtio_tx_route(dev, m, mbuf_pool, (uint16_t)dev->device_fh);
+		vq->last_used_idx++;
+		entry_success++;
+		rte_pktmbuf_free(m);
+	}
+
+	rte_compiler_barrier();
+	vq->used->idx += entry_success;
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+}
+
+/*
+ * This function is called by each data core. It handles all RX/TX registered with the
+ * core. For TX the specific lcore linked list is used. For RX, MAC addresses are compared
+ * with all devices in the main linked list.
+ */
+static int
+switch_worker(__attribute__((unused)) void *arg)
+{
+	struct rte_mempool *mbuf_pool = arg;
+	struct virtio_net *dev = NULL;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+	struct virtio_net_data_ll *dev_ll;
+	struct mbuf_table *tx_q;
+	volatile struct lcore_ll_info *lcore_ll;
+	const uint64_t drain_tsc = (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S * BURST_TX_DRAIN_US;
+	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
+	unsigned ret, i;
+	const uint16_t lcore_id = rte_lcore_id();
+	const uint16_t num_cores = (uint16_t)rte_lcore_count();
+	uint16_t rx_count = 0;
+	uint32_t mergeable = 0;
+
+	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
+	lcore_ll = lcore_info[lcore_id].lcore_ll;
+	prev_tsc = 0;
+
+	tx_q = &lcore_tx_queue[lcore_id];
+	for (i = 0; i < num_cores; i ++) {
+		if (lcore_ids[i] == lcore_id) {
+			tx_q->txq_id = i;
+			break;
+		}
+	}
+
+	while(1) {
+		cur_tsc = rte_rdtsc();
+		/*
+		 * TX burst queue drain
+		 */
+		diff_tsc = cur_tsc - prev_tsc;
+		if (unlikely(diff_tsc > drain_tsc)) {
+
+			if (tx_q->len) {
+				LOG_DEBUG(VHOST_DATA, "TX queue drained after timeout with burst size %u \n", tx_q->len);
+
+				/*Tx any packets in the queue*/
+				ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id,
+									   (struct rte_mbuf **)tx_q->m_table,
+									   (uint16_t)tx_q->len);
+				if (unlikely(ret < tx_q->len)) {
+					do {
+						rte_pktmbuf_free(tx_q->m_table[ret]);
+					} while (++ret < tx_q->len);
+				}
+
+				tx_q->len = 0;
+			}
+
+			prev_tsc = cur_tsc;
+
+		}
+
+		rte_prefetch0(lcore_ll->ll_root_used);
+		/*
+		 * Inform the configuration core that we have exited the linked list and that no devices are
+		 * in use if requested.
+		 */
+		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
+			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+
+		/*
+		 * Process devices
+		 */
+		dev_ll = lcore_ll->ll_root_used;
+
+		while (dev_ll != NULL) {
+			/*get virtio device ID*/
+			dev = dev_ll->dev;
+			mergeable =
+				dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
+
+			if (dev->remove) {
+				dev_ll = dev_ll->next;
+				unlink_vmdq(dev);
+				dev->ready = DEVICE_SAFE_REMOVE;
+				continue;
+			}
+			if (likely(dev->ready == DEVICE_RX)) {
+				/*Handle guest RX*/
+				rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+
+				if (rx_count) {
+					if (likely(mergeable == 0))
+						ret_count =
+							virtio_dev_rx(dev,
+							pkts_burst, rx_count);
+					else
+						ret_count =
+							virtio_dev_merge_rx(dev,
+							pkts_burst, rx_count);
+
+					if (enable_stats) {
+						rte_atomic64_add(
+						&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
+						rx_count);
+						rte_atomic64_add(
+						&dev_statistics[dev_ll->dev->device_fh].rx_atomic, ret_count);
+					}
+					while (likely(rx_count)) {
+						rx_count--;
+						rte_pktmbuf_free(pkts_burst[rx_count]);
+					}
+
+				}
+			}
+
+			if (!dev->remove) {
+				/*Handle guest TX*/
+				if (likely(mergeable == 0))
+					virtio_dev_tx(dev, mbuf_pool);
+				else
+					virtio_dev_merge_tx(dev, mbuf_pool);
+			}
+
+			/*move to the next device in the list*/
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * This function gets available ring number for zero copy rx.
+ * Only one thread will call this funciton for a paticular virtio device,
+ * so, it is designed as non-thread-safe function.
+ */
+static inline uint32_t __attribute__((always_inline))
+get_available_ring_num_zcp(struct virtio_net *dev)
+{
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
+	uint16_t avail_idx;
+
+	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+	return (uint32_t)(avail_idx - vq->last_used_idx_res);
+}
+
+/*
+ * This function gets available ring index for zero copy rx,
+ * it will retry 'burst_rx_retry_num' times till it get enough ring index.
+ * Only one thread will call this funciton for a paticular virtio device,
+ * so, it is designed as non-thread-safe function.
+ */
+static inline uint32_t __attribute__((always_inline))
+get_available_ring_index_zcp(struct virtio_net *dev,
+	uint16_t *res_base_idx, uint32_t count)
+{
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
+	uint16_t avail_idx;
+	uint32_t retry = 0;
+	uint16_t free_entries;
+
+	*res_base_idx = vq->last_used_idx_res;
+	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+	free_entries = (avail_idx - *res_base_idx);
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") in get_available_ring_index_zcp: "
+			"avail idx: %d, "
+			"res base idx:%d, free entries:%d\n",
+			dev->device_fh, avail_idx, *res_base_idx,
+			free_entries);
+
+	/*
+	 * If retry is enabled and the queue is full then we wait
+	 * and retry to avoid packet loss.
+	 */
+	if (enable_retry && unlikely(count > free_entries)) {
+		for (retry = 0; retry < burst_rx_retry_num; retry++) {
+			rte_delay_us(burst_rx_delay_time);
+			avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+			free_entries = (avail_idx - *res_base_idx);
+			if (count <= free_entries)
+				break;
+		}
+	}
+
+	/*check that we have enough buffers*/
+	if (unlikely(count > free_entries))
+		count = free_entries;
+
+	if (unlikely(count == 0)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") Fail in get_available_ring_index_zcp: "
+			"avail idx: %d, res base idx:%d, free entries:%d\n",
+			dev->device_fh, avail_idx,
+			*res_base_idx, free_entries);
+		return 0;
+	}
+
+	vq->last_used_idx_res = *res_base_idx + count;
+
+	return count;
+}
+
+/*
+ * This function put descriptor back to used list.
+ */
+static inline void __attribute__((always_inline))
+put_desc_to_used_list_zcp(struct vhost_virtqueue *vq, uint16_t desc_idx)
+{
+	uint16_t res_cur_idx = vq->last_used_idx;
+	vq->used->ring[res_cur_idx & (vq->size - 1)].id = (uint32_t)desc_idx;
+	vq->used->ring[res_cur_idx & (vq->size - 1)].len = 0;
+	rte_compiler_barrier();
+	*(volatile uint16_t *)&vq->used->idx += 1;
+	vq->last_used_idx += 1;
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+}
+
+/*
+ * This function get available descriptor from vitio vring and un-attached mbuf
+ * from vpool->ring, and then attach them together. It needs adjust the offset
+ * for buff_addr and phys_addr accroding to PMD implementation, otherwise the
+ * frame data may be put to wrong location in mbuf.
+ */
+static inline void __attribute__((always_inline))
+attach_rxmbuf_zcp(struct virtio_net *dev)
+{
+	uint16_t res_base_idx, desc_idx;
+	uint64_t buff_addr, phys_addr;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *mbuf = NULL;
+	struct vpool *vpool;
+	hpa_type addr_type;
+
+	vpool = &vpool_array[dev->vmdq_rx_q];
+	vq = dev->virtqueue[VIRTIO_RXQ];
+
+	do {
+		if (unlikely(get_available_ring_index_zcp(dev, &res_base_idx,
+				1) != 1))
+			return;
+		desc_idx = vq->avail->ring[(res_base_idx) & (vq->size - 1)];
+
+		desc = &vq->desc[desc_idx];
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc = &vq->desc[desc->next];
+			buff_addr = gpa_to_vva(dev, desc->addr);
+			phys_addr = gpa_to_hpa(dev, desc->addr, desc->len,
+					&addr_type);
+		} else {
+			buff_addr = gpa_to_vva(dev,
+					desc->addr + vq->vhost_hlen);
+			phys_addr = gpa_to_hpa(dev,
+					desc->addr + vq->vhost_hlen,
+					desc->len, &addr_type);
+		}
+
+		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
+			RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Invalid frame buffer"
+				" address found when attaching RX frame buffer"
+				" address!\n", dev->device_fh);
+			put_desc_to_used_list_zcp(vq, desc_idx);
+			continue;
+		}
+
+		/*
+		 * Check if the frame buffer address from guest crosses
+		 * sub-region or not.
+		 */
+		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Frame buffer address cross "
+				"sub-regioin found when attaching RX frame "
+				"buffer address!\n",
+				dev->device_fh);
+			put_desc_to_used_list_zcp(vq, desc_idx);
+			continue;
+		}
+	} while (unlikely(phys_addr == 0));
+
+	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
+	if (unlikely(mbuf == NULL)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in attach_rxmbuf_zcp: "
+			"ring_sc_dequeue fail.\n",
+			dev->device_fh);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		return;
+	}
+
+	if (unlikely(vpool->buf_size > desc->len)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in attach_rxmbuf_zcp: frame buffer "
+			"length(%d) of descriptor idx: %d less than room "
+			"size required: %d\n",
+			dev->device_fh, desc->len, desc_idx, vpool->buf_size);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
+		return;
+	}
+
+	mbuf->buf_addr = (void *)(uintptr_t)(buff_addr - RTE_PKTMBUF_HEADROOM);
+	mbuf->pkt.data = (void *)(uintptr_t)(buff_addr);
+	mbuf->buf_physaddr = phys_addr - RTE_PKTMBUF_HEADROOM;
+	mbuf->pkt.data_len = desc->len;
+	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in attach_rxmbuf_zcp: res base idx:%d, "
+		"descriptor idx:%d\n",
+		dev->device_fh, res_base_idx, desc_idx);
+
+	__rte_mbuf_raw_free(mbuf);
+
+	return;
+}
+
+/*
+ * Detach an attched packet mbuf -
+ *  - restore original mbuf address and length values.
+ *  - reset pktmbuf data and data_len to their default values.
+ *  All other fields of the given packet mbuf will be left intact.
+ *
+ * @param m
+ *   The attached packet mbuf.
+ */
+static inline void pktmbuf_detach_zcp(struct rte_mbuf *m)
+{
+	const struct rte_mempool *mp = m->pool;
+	void *buf = RTE_MBUF_TO_BADDR(m);
+	uint32_t buf_ofs;
+	uint32_t buf_len = mp->elt_size - sizeof(*m);
+	m->buf_physaddr = rte_mempool_virt2phy(mp, m) + sizeof(*m);
+
+	m->buf_addr = buf;
+	m->buf_len = (uint16_t)buf_len;
+
+	buf_ofs = (RTE_PKTMBUF_HEADROOM <= m->buf_len) ?
+			RTE_PKTMBUF_HEADROOM : m->buf_len;
+	m->pkt.data = (char *) m->buf_addr + buf_ofs;
+
+	m->pkt.data_len = 0;
+}
+
+/*
+ * This function is called after packets have been transimited. It fetchs mbuf
+ * from vpool->pool, detached it and put into vpool->ring. It also update the
+ * used index and kick the guest if necessary.
+ */
+static inline uint32_t __attribute__((always_inline))
+txmbuf_clean_zcp(struct virtio_net *dev, struct vpool *vpool)
+{
+	struct rte_mbuf *mbuf;
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
+	uint32_t used_idx = vq->last_used_idx & (vq->size - 1);
+	uint32_t index = 0;
+	uint32_t mbuf_count = rte_mempool_count(vpool->pool);
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool before "
+		"clean is: %d\n",
+		dev->device_fh, mbuf_count);
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring before "
+		"clean  is : %d\n",
+		dev->device_fh, rte_ring_count(vpool->ring));
+
+	for (index = 0; index < mbuf_count; index++) {
+		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
+		if (likely(RTE_MBUF_INDIRECT(mbuf)))
+			pktmbuf_detach_zcp(mbuf);
+		rte_ring_sp_enqueue(vpool->ring, mbuf);
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = MBUF_HEADROOM_UINT32(mbuf);
+		vq->used->ring[used_idx].len = 0;
+
+		used_idx = (used_idx + 1) & (vq->size - 1);
+	}
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool after "
+		"clean is: %d\n",
+		dev->device_fh, rte_mempool_count(vpool->pool));
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring after "
+		"clean  is : %d\n",
+		dev->device_fh, rte_ring_count(vpool->ring));
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: before updated "
+		"vq->last_used_idx:%d\n",
+		dev->device_fh, vq->last_used_idx);
+
+	vq->last_used_idx += mbuf_count;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: after updated "
+		"vq->last_used_idx:%d\n",
+		dev->device_fh, vq->last_used_idx);
+
+	rte_compiler_barrier();
+
+	*(volatile uint16_t *)&vq->used->idx += mbuf_count;
+
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+	return 0;
+}
+
+/*
+ * This function is called when a virtio device is destroy.
+ * It fetchs mbuf from vpool->pool, and detached it, and put into vpool->ring.
+ */
+static void mbuf_destroy_zcp(struct vpool *vpool)
+{
+	struct rte_mbuf *mbuf = NULL;
+	uint32_t index, mbuf_count = rte_mempool_count(vpool->pool);
+
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in mempool before "
+		"mbuf_destroy_zcp is: %d\n",
+		mbuf_count);
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in  ring before "
+		"mbuf_destroy_zcp  is : %d\n",
+		rte_ring_count(vpool->ring));
+
+	for (index = 0; index < mbuf_count; index++) {
+		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
+		if (likely(mbuf != NULL)) {
+			if (likely(RTE_MBUF_INDIRECT(mbuf)))
+				pktmbuf_detach_zcp(mbuf);
+			rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
+		}
+	}
+
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in mempool after "
+		"mbuf_destroy_zcp is: %d\n",
+		rte_mempool_count(vpool->pool));
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in ring after "
+		"mbuf_destroy_zcp is : %d\n",
+		rte_ring_count(vpool->ring));
+}
+
+/*
+ * This function update the use flag and counter.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_rx_zcp(struct virtio_net *dev, struct rte_mbuf **pkts,
+	uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *buff;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr
+		= {{0, 0, 0, 0, 0, 0}, 0};
+	uint64_t buff_hdr_addr = 0;
+	uint32_t head[MAX_PKT_BURST], packet_len = 0;
+	uint32_t head_idx, packet_success = 0;
+	uint16_t res_cur_idx;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
+
+	if (count == 0)
+		return 0;
+
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
+
+	res_cur_idx = vq->last_used_idx;
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n",
+		dev->device_fh, res_cur_idx, res_cur_idx + count);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (head_idx = 0; head_idx < count; head_idx++)
+		head[head_idx] = MBUF_HEADROOM_UINT32(pkts[head_idx]);
+
+	/*Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+
+	while (packet_success != count) {
+		/* Get descriptor from available ring */
+		desc = &vq->desc[head[packet_success]];
+
+		buff = pkts[packet_success];
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in dev_rx_zcp: update the used idx for "
+			"pkt[%d] descriptor idx: %d\n",
+			dev->device_fh, packet_success,
+			MBUF_HEADROOM_UINT32(buff));
+
+		PRINT_PACKET(dev,
+			(uintptr_t)(((uint64_t)(uintptr_t)buff->buf_addr)
+			+ RTE_PKTMBUF_HEADROOM),
+			rte_pktmbuf_data_len(buff), 0);
+
+		/* Buffer address translation for virtio header. */
+		buff_hdr_addr = gpa_to_vva(dev, desc->addr);
+		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+		/*
+		 * If the descriptors are chained the header and data are
+		 * placed in separate buffers.
+		 */
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc->len = vq->vhost_hlen;
+			desc = &vq->desc[desc->next];
+			desc->len = rte_pktmbuf_data_len(buff);
+		} else {
+			desc->len = packet_len;
+		}
+
+		/* Update used ring with desc information */
+		vq->used->ring[res_cur_idx & (vq->size - 1)].id
+			= head[packet_success];
+		vq->used->ring[res_cur_idx & (vq->size - 1)].len
+			= packet_len;
+		res_cur_idx++;
+		packet_success++;
+
+		/* A header is required per buffer. */
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
+			(const void *)&virtio_hdr, vq->vhost_hlen);
+
+		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+
+		if (likely(packet_success < count)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success]]);
+		}
+	}
+
+	rte_compiler_barrier();
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in dev_rx_zcp: before update used idx: "
+		"vq.last_used_idx: %d, vq->used->idx: %d\n",
+		dev->device_fh, vq->last_used_idx, vq->used->idx);
+
+	*(volatile uint16_t *)&vq->used->idx += count;
+	vq->last_used_idx += count;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in dev_rx_zcp: after  update used idx: "
+		"vq.last_used_idx: %d, vq->used->idx: %d\n",
+		dev->device_fh, vq->last_used_idx, vq->used->idx);
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+	return count;
+}
+
+/*
+ * This function routes the TX packet to the correct interface.
+ * This may be a local device or the physical port.
+ */
+static inline void __attribute__((always_inline))
+virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
+	uint32_t desc_idx, uint8_t need_copy)
+{
+	struct mbuf_table *tx_q;
+	struct rte_mbuf **m_table;
+	struct rte_mbuf *mbuf = NULL;
+	unsigned len, ret, offset = 0;
+	struct vpool *vpool;
+	struct virtio_net_data_ll *dev_ll = ll_root_used;
+	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
+	uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
+
+	/*Add packet to the port tx queue*/
+	tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+	len = tx_q->len;
+
+	/* Allocate an mbuf and populate the structure. */
+	vpool = &vpool_array[MAX_QUEUES + (uint16_t)dev->vmdq_rx_q];
+	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
+	if (unlikely(mbuf == NULL)) {
+		struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
+		RTE_LOG(ERR, VHOST_DATA,
+			"(%"PRIu64") Failed to allocate memory for mbuf.\n",
+			dev->device_fh);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		return;
+	}
+
+	if (vm2vm_mode == VM2VM_HARDWARE) {
+		/* Avoid using a vlan tag from any vm for external pkt, such as
+		 * vlan_tags[dev->device_fh], oterwise, it conflicts when pool
+		 * selection, MAC address determines it as an external pkt
+		 * which should go to network, while vlan tag determine it as
+		 * a vm2vm pkt should forward to another vm. Hardware confuse
+		 * such a ambiguous situation, so pkt will lost.
+		 */
+		vlan_tag = external_pkt_default_vlan_tag;
+		while (dev_ll != NULL) {
+			if (likely(dev_ll->dev->ready == DEVICE_RX) &&
+				ether_addr_cmp(&(pkt_hdr->d_addr),
+				&dev_ll->dev->mac_address)) {
+
+				/*
+				 * Drop the packet if the TX packet is destined
+				 * for the TX device.
+				 */
+				if (unlikely(dev_ll->dev->device_fh
+					== dev->device_fh)) {
+					LOG_DEBUG(VHOST_DATA,
+					"(%"PRIu64") TX: Source and destination"
+					"MAC addresses are the same. Dropping "
+					"packet.\n",
+					dev_ll->dev->device_fh);
+					MBUF_HEADROOM_UINT32(mbuf)
+						= (uint32_t)desc_idx;
+					__rte_mbuf_raw_free(mbuf);
+					return;
+				}
+
+				/*
+				 * Packet length offset 4 bytes for HW vlan
+				 * strip when L2 switch back.
+				 */
+				offset = 4;
+				vlan_tag =
+				(uint16_t)
+				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
+
+				LOG_DEBUG(VHOST_DATA,
+				"(%"PRIu64") TX: pkt to local VM device id:"
+				"(%"PRIu64") vlan tag: %d.\n",
+				dev->device_fh, dev_ll->dev->device_fh,
+				vlan_tag);
+
+				break;
+			}
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	mbuf->pkt.nb_segs = m->pkt.nb_segs;
+	mbuf->pkt.next = m->pkt.next;
+	mbuf->pkt.data_len = m->pkt.data_len + offset;
+	mbuf->pkt.pkt_len = mbuf->pkt.data_len;
+	if (unlikely(need_copy)) {
+		/* Copy the packet contents to the mbuf. */
+		rte_memcpy((void *)((uint8_t *)mbuf->pkt.data),
+			(const void *) ((uint8_t *)m->pkt.data),
+			m->pkt.data_len);
+	} else {
+		mbuf->pkt.data = m->pkt.data;
+		mbuf->buf_physaddr = m->buf_physaddr;
+		mbuf->buf_addr = m->buf_addr;
+	}
+	mbuf->ol_flags = PKT_TX_VLAN_PKT;
+	mbuf->pkt.vlan_macip.f.vlan_tci = vlan_tag;
+	mbuf->pkt.vlan_macip.f.l2_len = sizeof(struct ether_hdr);
+	mbuf->pkt.vlan_macip.f.l3_len = sizeof(struct ipv4_hdr);
+	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
+
+	tx_q->m_table[len] = mbuf;
+	len++;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in tx_route_zcp: pkt: nb_seg: %d, next:%s\n",
+		dev->device_fh,
+		mbuf->pkt.nb_segs,
+		(mbuf->pkt.next == NULL) ? "null" : "non-null");
+
+	if (enable_stats) {
+		dev_statistics[dev->device_fh].tx_total++;
+		dev_statistics[dev->device_fh].tx++;
+	}
+
+	if (unlikely(len == MAX_PKT_BURST)) {
+		m_table = (struct rte_mbuf **)tx_q->m_table;
+		ret = rte_eth_tx_burst(ports[0],
+			(uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
+
+		/*
+		 * Free any buffers not handled by TX and update
+		 * the port stats.
+		 */
+		if (unlikely(ret < len)) {
+			do {
+				rte_pktmbuf_free(m_table[ret]);
+			} while (++ret < len);
+		}
+
+		len = 0;
+		txmbuf_clean_zcp(dev, vpool);
+	}
+
+	tx_q->len = len;
+
+	return;
+}
+
+/*
+ * This function TX all available packets in virtio TX queue for one
+ * virtio-net device. If it is first packet, it learns MAC address and
+ * setup VMDQ.
+ */
+static inline void __attribute__((always_inline))
+virtio_dev_tx_zcp(struct virtio_net *dev)
+{
+	struct rte_mbuf m;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t buff_addr = 0, phys_addr;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t i;
+	uint16_t free_entries, packet_success = 0;
+	uint16_t avail_idx;
+	uint8_t need_copy = 0;
+	hpa_type addr_type;
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx_res == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx_res & (vq->size - 1)]);
+
+	/* Get the number of free entries in the ring */
+	free_entries = (avail_idx - vq->last_used_idx_res);
+
+	/* Limit to MAX_PKT_BURST. */
+	free_entries
+		= (free_entries > MAX_PKT_BURST) ? MAX_PKT_BURST : free_entries;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
+		dev->device_fh, free_entries);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i]
+			= vq->avail->ring[(vq->last_used_idx_res + i)
+			& (vq->size - 1)];
+
+	vq->last_used_idx_res += free_entries;
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (packet_success < free_entries) {
+		desc = &vq->desc[head[packet_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		phys_addr = gpa_to_hpa(dev, desc->addr, desc->len, &addr_type);
+
+		if (likely(packet_success < (free_entries - 1)))
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success + 1]]);
+
+		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Invalid frame buffer address found"
+				"when TX packets!\n",
+				dev->device_fh);
+			packet_success++;
+			continue;
+		}
+
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)buff_addr);
+
+		/*
+		 * Setup dummy mbuf. This is copied to a real mbuf if
+		 * transmitted out the physical port.
+		 */
+		m.pkt.data_len = desc->len;
+		m.pkt.nb_segs = 1;
+		m.pkt.next = NULL;
+		m.pkt.data = (void *)(uintptr_t)buff_addr;
+		m.buf_addr = m.pkt.data;
+		m.buf_physaddr = phys_addr;
+
+		/*
+		 * Check if the frame buffer address from guest crosses
+		 * sub-region or not.
+		 */
+		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Frame buffer address cross "
+				"sub-regioin found when attaching TX frame "
+				"buffer address!\n",
+				dev->device_fh);
+			need_copy = 1;
+		} else
+			need_copy = 0;
+
+		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+
+		/*
+		 * If this is the first received packet we need to learn
+		 * the MAC and setup VMDQ
+		 */
+		if (unlikely(dev->ready == DEVICE_MAC_LEARNING)) {
+			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
+				/*
+				 * Discard frame if device is scheduled for
+				 * removal or a duplicate MAC address is found.
+				 */
+				packet_success += free_entries;
+				vq->last_used_idx += packet_success;
+				break;
+			}
+		}
+
+		virtio_tx_route_zcp(dev, &m, head[packet_success], need_copy);
+		packet_success++;
+	}
+}
+
+/*
+ * This function is called by each data core. It handles all RX/TX registered
+ * with the core. For TX the specific lcore linked list is used. For RX, MAC
+ * addresses are compared with all devices in the main linked list.
+ */
+static int
+switch_worker_zcp(__attribute__((unused)) void *arg)
+{
+	struct virtio_net *dev = NULL;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+	struct virtio_net_data_ll *dev_ll;
+	struct mbuf_table *tx_q;
+	volatile struct lcore_ll_info *lcore_ll;
+	const uint64_t drain_tsc
+		= (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S
+		* BURST_TX_DRAIN_US;
+	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
+	unsigned ret;
+	const uint16_t lcore_id = rte_lcore_id();
+	uint16_t count_in_ring, rx_count = 0;
+
+	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
+
+	lcore_ll = lcore_info[lcore_id].lcore_ll;
+	prev_tsc = 0;
+
+	while (1) {
+		cur_tsc = rte_rdtsc();
+
+		/* TX burst queue drain */
+		diff_tsc = cur_tsc - prev_tsc;
+		if (unlikely(diff_tsc > drain_tsc)) {
+			/*
+			 * Get mbuf from vpool.pool and detach mbuf and
+			 * put back into vpool.ring.
+			 */
+			dev_ll = lcore_ll->ll_root_used;
+			while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
+				/* Get virtio device ID */
+				dev = dev_ll->dev;
+
+				if (likely(!dev->remove)) {
+					tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+					if (tx_q->len) {
+						LOG_DEBUG(VHOST_DATA,
+						"TX queue drained after timeout"
+						" with burst size %u\n",
+						tx_q->len);
+
+						/*
+						 * Tx any packets in the queue
+						 */
+						ret = rte_eth_tx_burst(
+							ports[0],
+							(uint16_t)tx_q->txq_id,
+							(struct rte_mbuf **)
+							tx_q->m_table,
+							(uint16_t)tx_q->len);
+						if (unlikely(ret < tx_q->len)) {
+							do {
+								rte_pktmbuf_free(
+									tx_q->m_table[ret]);
+							} while (++ret < tx_q->len);
+						}
+						tx_q->len = 0;
+
+						txmbuf_clean_zcp(dev,
+							&vpool_array[MAX_QUEUES+dev->vmdq_rx_q]);
+					}
+				}
+				dev_ll = dev_ll->next;
+			}
+			prev_tsc = cur_tsc;
+		}
+
+		rte_prefetch0(lcore_ll->ll_root_used);
+
+		/*
+		 * Inform the configuration core that we have exited the linked
+		 * list and that no devices are in use if requested.
+		 */
+		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
+			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+
+		/* Process devices */
+		dev_ll = lcore_ll->ll_root_used;
+
+		while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
+			dev = dev_ll->dev;
+			if (unlikely(dev->remove)) {
+				dev_ll = dev_ll->next;
+				unlink_vmdq(dev);
+				dev->ready = DEVICE_SAFE_REMOVE;
+				continue;
+			}
+
+			if (likely(dev->ready == DEVICE_RX)) {
+				uint32_t index = dev->vmdq_rx_q;
+				uint16_t i;
+				count_in_ring
+				= rte_ring_count(vpool_array[index].ring);
+				uint16_t free_entries
+				= (uint16_t)get_available_ring_num_zcp(dev);
+
+				/*
+				 * Attach all mbufs in vpool.ring and put back
+				 * into vpool.pool.
+				 */
+				for (i = 0;
+				i < RTE_MIN(free_entries,
+				RTE_MIN(count_in_ring, MAX_PKT_BURST));
+				i++)
+					attach_rxmbuf_zcp(dev);
+
+				/* Handle guest RX */
+				rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst,
+					MAX_PKT_BURST);
+
+				if (rx_count) {
+					ret_count = virtio_dev_rx_zcp(dev,
+							pkts_burst, rx_count);
+					if (enable_stats) {
+						dev_statistics[dev->device_fh].rx_total
+							+= rx_count;
+						dev_statistics[dev->device_fh].rx
+							+= ret_count;
+					}
+					while (likely(rx_count)) {
+						rx_count--;
+						pktmbuf_detach_zcp(
+							pkts_burst[rx_count]);
+						rte_ring_sp_enqueue(
+							vpool_array[index].ring,
+							(void *)pkts_burst[rx_count]);
+					}
+				}
+			}
+
+			if (likely(!dev->remove))
+				/* Handle guest TX */
+				virtio_dev_tx_zcp(dev);
+
+			/* Move to the next device in the list */
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	return 0;
+}
+
+
+/*
+ * Add an entry to a used linked list. A free entry must first be found
+ * in the free linked list using get_data_ll_free_entry();
+ */
+static void
+add_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev)
+{
+	struct virtio_net_data_ll *ll = *ll_root_addr;
+
+	/* Set next as NULL and use a compiler barrier to avoid reordering. */
+	ll_dev->next = NULL;
+	rte_compiler_barrier();
+
+	/* If ll == NULL then this is the first device. */
+	if (ll) {
+		/* Increment to the tail of the linked list. */
+		while ((ll->next != NULL) )
+			ll = ll->next;
+
+		ll->next = ll_dev;
+	} else {
+		*ll_root_addr = ll_dev;
+	}
+}
+
+/*
+ * Remove an entry from a used linked list. The entry must then be added to
+ * the free linked list using put_data_ll_free_entry().
+ */
+static void
+rm_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev,
+	struct virtio_net_data_ll *ll_dev_last)
+{
+	struct virtio_net_data_ll *ll = *ll_root_addr;
+
+	if (unlikely((ll == NULL) || (ll_dev == NULL)))
+		return;
+
+	if (ll_dev == ll)
+		*ll_root_addr = ll_dev->next;
+	else
+		if (likely(ll_dev_last != NULL))
+			ll_dev_last->next = ll_dev->next;
+		else
+			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry form ll failed.\n");
+}
+
+/*
+ * Find and return an entry from the free linked list.
+ */
+static struct virtio_net_data_ll *
+get_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr)
+{
+	struct virtio_net_data_ll *ll_free = *ll_root_addr;
+	struct virtio_net_data_ll *ll_dev;
+
+	if (ll_free == NULL)
+		return NULL;
+
+	ll_dev = ll_free;
+	*ll_root_addr = ll_free->next;
+
+	return ll_dev;
+}
+
+/*
+ * Place an entry back on to the free linked list.
+ */
+static void
+put_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev)
+{
+	struct virtio_net_data_ll *ll_free = *ll_root_addr;
+
+	if (ll_dev == NULL)
+		return;
+
+	ll_dev->next = ll_free;
+	*ll_root_addr = ll_dev;
+}
+
+/*
+ * Creates a linked list of a given size.
+ */
+static struct virtio_net_data_ll *
+alloc_data_ll(uint32_t size)
+{
+	struct virtio_net_data_ll *ll_new;
+	uint32_t i;
+
+	/* Malloc and then chain the linked list. */
+	ll_new = malloc(size * sizeof(struct virtio_net_data_ll));
+	if (ll_new == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for ll_new.\n");
+		return NULL;
+	}
+
+	for (i = 0; i < size - 1; i++) {
+		ll_new[i].dev = NULL;
+		ll_new[i].next = &ll_new[i+1];
+	}
+	ll_new[i].next = NULL;
+
+	return (ll_new);
+}
+
+/*
+ * Create the main linked list along with each individual cores linked list. A used and a free list
+ * are created to manage entries.
+ */
+static int
+init_data_ll (void)
+{
+	int lcore;
+
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		lcore_info[lcore].lcore_ll = malloc(sizeof(struct lcore_ll_info));
+		if (lcore_info[lcore].lcore_ll == NULL) {
+			RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for lcore_ll.\n");
+			return -1;
+		}
+
+		lcore_info[lcore].lcore_ll->device_num = 0;
+		lcore_info[lcore].lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+		lcore_info[lcore].lcore_ll->ll_root_used = NULL;
+		if (num_devices % num_switching_cores)
+			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll((num_devices / num_switching_cores) + 1);
+		else
+			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll(num_devices / num_switching_cores);
+	}
+
+	/* Allocate devices up to a maximum of MAX_DEVICES. */
+	ll_root_free = alloc_data_ll(MIN((num_devices), MAX_DEVICES));
+
+	return 0;
+}
+
+/*
+ * Set virtqueue flags so that we do not receive interrupts.
+ */
+static void
+set_irq_status (struct virtio_net *dev)
+{
+	dev->virtqueue[VIRTIO_RXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
+	dev->virtqueue[VIRTIO_TXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
+}
+
+/*
+ * Remove a device from the specific data core linked list and from the main linked list. Synchonization
+ * occurs through the use of the lcore dev_removal_flag. Device is made volatile here to avoid re-ordering
+ * of dev->remove=1 which can cause an infinite loop in the rte_pause loop.
+ */
+static void
+destroy_device (volatile struct virtio_net *dev)
+{
+	struct virtio_net_data_ll *ll_lcore_dev_cur;
+	struct virtio_net_data_ll *ll_main_dev_cur;
+	struct virtio_net_data_ll *ll_lcore_dev_last = NULL;
+	struct virtio_net_data_ll *ll_main_dev_last = NULL;
+	int lcore;
+
+	dev->flags &= ~VIRTIO_DEV_RUNNING;
+
+	/*set the remove flag. */
+	dev->remove = 1;
+
+	while(dev->ready != DEVICE_SAFE_REMOVE) {
+		rte_pause();
+	}
+
+	/* Search for entry to be removed from lcore ll */
+	ll_lcore_dev_cur = lcore_info[dev->coreid].lcore_ll->ll_root_used;
+	while (ll_lcore_dev_cur != NULL) {
+		if (ll_lcore_dev_cur->dev == dev) {
+			break;
+		} else {
+			ll_lcore_dev_last = ll_lcore_dev_cur;
+			ll_lcore_dev_cur = ll_lcore_dev_cur->next;
+		}
+	}
+
+	if (ll_lcore_dev_cur == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to find the dev to be destroy.\n",
+			dev->device_fh);
+		return;
+	}
+
+	/* Search for entry to be removed from main ll */
+	ll_main_dev_cur = ll_root_used;
+	ll_main_dev_last = NULL;
+	while (ll_main_dev_cur != NULL) {
+		if (ll_main_dev_cur->dev == dev) {
+			break;
+		} else {
+			ll_main_dev_last = ll_main_dev_cur;
+			ll_main_dev_cur = ll_main_dev_cur->next;
+		}
+	}
+
+	/* Remove entries from the lcore and main ll. */
+	rm_data_ll_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_used, ll_lcore_dev_cur, ll_lcore_dev_last);
+	rm_data_ll_entry(&ll_root_used, ll_main_dev_cur, ll_main_dev_last);
+
+	/* Set the dev_removal_flag on each lcore. */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		lcore_info[lcore].lcore_ll->dev_removal_flag = REQUEST_DEV_REMOVAL;
+	}
+
+	/*
+	 * Once each core has set the dev_removal_flag to ACK_DEV_REMOVAL we can be sure that
+	 * they can no longer access the device removed from the linked lists and that the devices
+	 * are no longer in use.
+	 */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		while (lcore_info[lcore].lcore_ll->dev_removal_flag != ACK_DEV_REMOVAL) {
+			rte_pause();
+		}
+	}
+
+	/* Add the entries back to the lcore and main free ll.*/
+	put_data_ll_free_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_free, ll_lcore_dev_cur);
+	put_data_ll_free_entry(&ll_root_free, ll_main_dev_cur);
+
+	/* Decrement number of device on the lcore. */
+	lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->device_num--;
+
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been removed from data core\n", dev->device_fh);
+
+	if (zero_copy) {
+		struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+		/* Stop the RX queue. */
+		if (rte_eth_dev_rx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In destroy_device: Failed to stop "
+				"rx queue:%d\n",
+				dev->device_fh,
+				dev->vmdq_rx_q);
+		}
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in destroy_device: Start put mbuf in "
+			"mempool back to ring for RX queue: %d\n",
+			dev->device_fh, dev->vmdq_rx_q);
+
+		mbuf_destroy_zcp(vpool);
+
+		/* Stop the TX queue. */
+		if (rte_eth_dev_tx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In destroy_device: Failed to "
+				"stop tx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+		}
+
+		vpool = &vpool_array[dev->vmdq_rx_q + MAX_QUEUES];
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") destroy_device: Start put mbuf in mempool "
+			"back to ring for TX queue: %d, dev:(%"PRIu64")\n",
+			dev->device_fh, (dev->vmdq_rx_q + MAX_QUEUES),
+			dev->device_fh);
+
+		mbuf_destroy_zcp(vpool);
+	}
+
+}
+
+/*
+ * A new device is added to a data core. First the device is added to the main linked list
+ * and the allocated to a specific data core.
+ */
+static int
+new_device (struct virtio_net *dev)
+{
+	struct virtio_net_data_ll *ll_dev;
+	int lcore, core_add = 0;
+	uint32_t device_num_min = num_devices;
+
+	/* Add device to main ll */
+	ll_dev = get_data_ll_free_entry(&ll_root_free);
+	if (ll_dev == NULL) {
+		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") No free entry found in linked list. Device limit "
+			"of %d devices per core has been reached\n",
+			dev->device_fh, num_devices);
+		return -1;
+	}
+	ll_dev->dev = dev;
+	add_data_ll_entry(&ll_root_used, ll_dev);
+	ll_dev->dev->vmdq_rx_q
+		= ll_dev->dev->device_fh * (num_queues / num_devices);
+
+	if (zero_copy) {
+		uint32_t index = ll_dev->dev->vmdq_rx_q;
+		uint32_t count_in_ring, i;
+		struct mbuf_table *tx_q;
+
+		count_in_ring = rte_ring_count(vpool_array[index].ring);
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in new_device: mbuf count in mempool "
+			"before attach is: %d\n",
+			dev->device_fh,
+			rte_mempool_count(vpool_array[index].pool));
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in new_device: mbuf count in  ring "
+			"before attach  is : %d\n",
+			dev->device_fh, count_in_ring);
+
+		/*
+		 * Attach all mbufs in vpool.ring and put back intovpool.pool.
+		 */
+		for (i = 0; i < count_in_ring; i++)
+			attach_rxmbuf_zcp(dev);
+
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
+			"mempool after attach is: %d\n",
+			dev->device_fh,
+			rte_mempool_count(vpool_array[index].pool));
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
+			"ring after attach  is : %d\n",
+			dev->device_fh,
+			rte_ring_count(vpool_array[index].ring));
+
+		tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+		tx_q->txq_id = dev->vmdq_rx_q;
+
+		if (rte_eth_dev_tx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
+			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In new_device: Failed to start "
+				"tx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+
+			mbuf_destroy_zcp(vpool);
+			return -1;
+		}
+
+		if (rte_eth_dev_rx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
+			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In new_device: Failed to start "
+				"rx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+
+			/* Stop the TX queue. */
+			if (rte_eth_dev_tx_queue_stop(ports[0],
+				dev->vmdq_rx_q) != 0) {
+				LOG_DEBUG(VHOST_CONFIG,
+					"(%"PRIu64") In new_device: Failed to "
+					"stop tx queue:%d\n",
+					dev->device_fh, dev->vmdq_rx_q);
+			}
+
+			mbuf_destroy_zcp(vpool);
+			return -1;
+		}
+
+	}
+
+	/*reset ready flag*/
+	dev->ready = DEVICE_MAC_LEARNING;
+	dev->remove = 0;
+
+	/* Find a suitable lcore to add the device. */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		if (lcore_info[lcore].lcore_ll->device_num < device_num_min) {
+			device_num_min = lcore_info[lcore].lcore_ll->device_num;
+			core_add = lcore;
+		}
+	}
+	/* Add device to lcore ll */
+	ll_dev->dev->coreid = core_add;
+	ll_dev = get_data_ll_free_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_free);
+	if (ll_dev == NULL) {
+		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
+		dev->ready = DEVICE_SAFE_REMOVE;
+		destroy_device(dev);
+		return -1;
+	}
+	ll_dev->dev = dev;
+	add_data_ll_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_used, ll_dev);
+
+	/* Initialize device stats */
+	memset(&dev_statistics[dev->device_fh], 0, sizeof(struct device_statistics));
+
+	/* Disable notifications. */
+	set_irq_status(dev);
+	lcore_info[ll_dev->dev->coreid].lcore_ll->device_num++;
+	dev->flags |= VIRTIO_DEV_RUNNING;
+
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, dev->coreid);
+
+	return 0;
+}
+
+/*
+ * These callback allow devices to be added to the data core when configuration
+ * has been fully complete.
+ */
+static const struct virtio_net_device_ops virtio_net_device_ops =
+{
+	.new_device =  new_device,
+	.destroy_device = destroy_device,
+};
+
+/*
+ * This is a thread will wake up after a period to print stats if the user has
+ * enabled them.
+ */
+static void
+print_stats(void)
+{
+	struct virtio_net_data_ll *dev_ll;
+	uint64_t tx_dropped, rx_dropped;
+	uint64_t tx, tx_total, rx, rx_total;
+	uint32_t device_fh;
+	const char clr[] = { 27, '[', '2', 'J', '\0' };
+	const char top_left[] = { 27, '[', '1', ';', '1', 'H','\0' };
+
+	while(1) {
+		sleep(enable_stats);
+
+		/* Clear screen and move to top left */
+		printf("%s%s", clr, top_left);
+
+		printf("\nDevice statistics ====================================");
+
+		dev_ll = ll_root_used;
+		while (dev_ll != NULL) {
+			device_fh = (uint32_t)dev_ll->dev->device_fh;
+			tx_total = dev_statistics[device_fh].tx_total;
+			tx = dev_statistics[device_fh].tx;
+			tx_dropped = tx_total - tx;
+			if (zero_copy == 0) {
+				rx_total = rte_atomic64_read(
+					&dev_statistics[device_fh].rx_total_atomic);
+				rx = rte_atomic64_read(
+					&dev_statistics[device_fh].rx_atomic);
+			} else {
+				rx_total = dev_statistics[device_fh].rx_total;
+				rx = dev_statistics[device_fh].rx;
+			}
+			rx_dropped = rx_total - rx;
+
+			printf("\nStatistics for device %"PRIu32" ------------------------------"
+					"\nTX total: 		%"PRIu64""
+					"\nTX dropped: 		%"PRIu64""
+					"\nTX successful: 		%"PRIu64""
+					"\nRX total: 		%"PRIu64""
+					"\nRX dropped: 		%"PRIu64""
+					"\nRX successful: 		%"PRIu64"",
+					device_fh,
+					tx_total,
+					tx_dropped,
+					tx,
+					rx_total,
+					rx_dropped,
+					rx);
+
+			dev_ll = dev_ll->next;
+		}
+		printf("\n======================================================\n");
+	}
+}
+
+static void
+setup_mempool_tbl(int socket, uint32_t index, char *pool_name,
+	char *ring_name, uint32_t nb_mbuf)
+{
+	uint16_t roomsize = VIRTIO_DESCRIPTOR_LEN_ZCP + RTE_PKTMBUF_HEADROOM;
+	vpool_array[index].pool
+		= rte_mempool_create(pool_name, nb_mbuf, MBUF_SIZE_ZCP,
+		MBUF_CACHE_SIZE_ZCP, sizeof(struct rte_pktmbuf_pool_private),
+		rte_pktmbuf_pool_init, (void *)(uintptr_t)roomsize,
+		rte_pktmbuf_init, NULL, socket, 0);
+	if (vpool_array[index].pool != NULL) {
+		vpool_array[index].ring
+			= rte_ring_create(ring_name,
+				rte_align32pow2(nb_mbuf + 1),
+				socket, RING_F_SP_ENQ | RING_F_SC_DEQ);
+		if (likely(vpool_array[index].ring != NULL)) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"in setup_mempool_tbl: mbuf count in "
+				"mempool is: %d\n",
+				rte_mempool_count(vpool_array[index].pool));
+			LOG_DEBUG(VHOST_CONFIG,
+				"in setup_mempool_tbl: mbuf count in "
+				"ring   is: %d\n",
+				rte_ring_count(vpool_array[index].ring));
+		} else {
+			rte_exit(EXIT_FAILURE, "ring_create(%s) failed",
+				ring_name);
+		}
+
+		/* Need consider head room. */
+		vpool_array[index].buf_size = roomsize - RTE_PKTMBUF_HEADROOM;
+	} else {
+		rte_exit(EXIT_FAILURE, "mempool_create(%s) failed", pool_name);
+	}
+}
+
+
+/*
+ * Main function, does initialisation and calls the per-lcore functions. The CUSE
+ * device is also registered here to handle the IOCTLs.
+ */
+int
+MAIN(int argc, char *argv[])
+{
+	struct rte_mempool *mbuf_pool = NULL;
+	unsigned lcore_id, core_id = 0;
+	unsigned nb_ports, valid_num_ports;
+	int ret;
+	uint8_t portid, queue_id = 0;
+	static pthread_t tid;
+
+	/* init EAL */
+	ret = rte_eal_init(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Error with EAL initialization\n");
+	argc -= ret;
+	argv += ret;
+
+	/* parse app arguments */
+	ret = us_vhost_parse_args(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Invalid argument\n");
+
+	if (rte_eal_pci_probe() != 0)
+		rte_exit(EXIT_FAILURE, "Error with NIC driver initialization\n");
+
+	for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id ++)
+		if (rte_lcore_is_enabled(lcore_id))
+			lcore_ids[core_id ++] = lcore_id;
+
+	if (rte_lcore_count() > RTE_MAX_LCORE)
+		rte_exit(EXIT_FAILURE,"Not enough cores\n");
+
+	/*set the number of swithcing cores available*/
+	num_switching_cores = rte_lcore_count()-1;
+
+	/* Get the number of physical ports. */
+	nb_ports = rte_eth_dev_count();
+	if (nb_ports > RTE_MAX_ETHPORTS)
+		nb_ports = RTE_MAX_ETHPORTS;
+
+	/*
+	 * Update the global var NUM_PORTS and global array PORTS
+	 * and get value of var VALID_NUM_PORTS according to system ports number
+	 */
+	valid_num_ports = check_ports_num(nb_ports);
+
+	if ((valid_num_ports ==  0) || (valid_num_ports > MAX_SUP_PORTS)) {
+		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
+			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
+		return -1;
+	}
+
+	if (zero_copy == 0) {
+		/* Create the mbuf pool. */
+		mbuf_pool = rte_mempool_create(
+				"MBUF_POOL",
+				NUM_MBUFS_PER_PORT
+				* valid_num_ports,
+				MBUF_SIZE, MBUF_CACHE_SIZE,
+				sizeof(struct rte_pktmbuf_pool_private),
+				rte_pktmbuf_pool_init, NULL,
+				rte_pktmbuf_init, NULL,
+				rte_socket_id(), 0);
+		if (mbuf_pool == NULL)
+			rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
+
+		for (queue_id = 0; queue_id < MAX_QUEUES + 1; queue_id++)
+			vpool_array[queue_id].pool = mbuf_pool;
+
+		if (vm2vm_mode == VM2VM_HARDWARE) {
+			/* Enable VT loop back to let L2 switch to do it. */
+			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
+			LOG_DEBUG(VHOST_CONFIG,
+				"Enable loop back for L2 switch in vmdq.\n");
+		}
+	} else {
+		uint32_t nb_mbuf;
+		char pool_name[RTE_MEMPOOL_NAMESIZE];
+		char ring_name[RTE_MEMPOOL_NAMESIZE];
+
+		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
+		rx_conf_default.rx_drop_en = 0;
+		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
+		nb_mbuf = num_rx_descriptor
+			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
+			+ num_switching_cores * MAX_PKT_BURST;
+
+		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
+			snprintf(pool_name, sizeof(pool_name),
+				"rxmbuf_pool_%u", queue_id);
+			snprintf(ring_name, sizeof(ring_name),
+				"rxmbuf_ring_%u", queue_id);
+			setup_mempool_tbl(rte_socket_id(), queue_id,
+				pool_name, ring_name, nb_mbuf);
+		}
+
+		nb_mbuf = num_tx_descriptor
+				+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
+				+ num_switching_cores * MAX_PKT_BURST;
+
+		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
+			snprintf(pool_name, sizeof(pool_name),
+				"txmbuf_pool_%u", queue_id);
+			snprintf(ring_name, sizeof(ring_name),
+				"txmbuf_ring_%u", queue_id);
+			setup_mempool_tbl(rte_socket_id(),
+				(queue_id + MAX_QUEUES),
+				pool_name, ring_name, nb_mbuf);
+		}
+
+		if (vm2vm_mode == VM2VM_HARDWARE) {
+			/* Enable VT loop back to let L2 switch to do it. */
+			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
+			LOG_DEBUG(VHOST_CONFIG,
+				"Enable loop back for L2 switch in vmdq.\n");
+		}
+	}
+	/* Set log level. */
+	rte_set_log_level(LOG_LEVEL);
+
+	/* initialize all ports */
+	for (portid = 0; portid < nb_ports; portid++) {
+		/* skip ports that are not enabled */
+		if ((enabled_port_mask & (1 << portid)) == 0) {
+			RTE_LOG(INFO, VHOST_PORT,
+				"Skipping disabled port %d\n", portid);
+			continue;
+		}
+		if (port_init(portid) != 0)
+			rte_exit(EXIT_FAILURE,
+				"Cannot initialize network ports\n");
+	}
+
+	/* Initialise all linked lists. */
+	if (init_data_ll() == -1)
+		rte_exit(EXIT_FAILURE, "Failed to initialize linked list\n");
+
+	/* Initialize device stats */
+	memset(&dev_statistics, 0, sizeof(dev_statistics));
+
+	/* Enable stats if the user option is set. */
+	if (enable_stats)
+		pthread_create(&tid, NULL, (void*)print_stats, NULL );
+
+	/* Launch all data cores. */
+	if (zero_copy == 0) {
+		RTE_LCORE_FOREACH_SLAVE(lcore_id) {
+			rte_eal_remote_launch(switch_worker,
+				mbuf_pool, lcore_id);
+		}
+	} else {
+		uint32_t count_in_mempool, index, i;
+		for (index = 0; index < 2*MAX_QUEUES; index++) {
+			/* For all RX and TX queues. */
+			count_in_mempool
+				= rte_mempool_count(vpool_array[index].pool);
+
+			/*
+			 * Transfer all un-attached mbufs from vpool.pool
+			 * to vpoo.ring.
+			 */
+			for (i = 0; i < count_in_mempool; i++) {
+				struct rte_mbuf *mbuf
+					= __rte_mbuf_raw_alloc(
+						vpool_array[index].pool);
+				rte_ring_sp_enqueue(vpool_array[index].ring,
+						(void *)mbuf);
+			}
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"in MAIN: mbuf count in mempool at initial "
+				"is: %d\n", count_in_mempool);
+			LOG_DEBUG(VHOST_CONFIG,
+				"in MAIN: mbuf count in  ring at initial  is :"
+				" %d\n",
+				rte_ring_count(vpool_array[index].ring));
+		}
+
+		RTE_LCORE_FOREACH_SLAVE(lcore_id)
+			rte_eal_remote_launch(switch_worker_zcp, NULL,
+				lcore_id);
+	}
+
+	/* Register CUSE device to handle IOCTLs. */
+	ret = register_cuse_device((char*)&dev_basename, dev_index, get_virtio_net_callbacks());
+	if (ret != 0)
+		rte_exit(EXIT_FAILURE,"CUSE device setup failure.\n");
+
+	init_virtio_net(&virtio_net_device_ops);
+
+	/* Start CUSE session. */
+	start_cuse_session_loop();
+	return 0;
+
+}
+
diff --git a/lib/librte_vhost/main.h b/lib/librte_vhost/main.h
new file mode 100644
index 0000000..c15d938
--- /dev/null
+++ b/lib/librte_vhost/main.h
@@ -0,0 +1,86 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _MAIN_H_
+#define _MAIN_H_
+
+#ifdef RTE_EXEC_ENV_BAREMETAL
+#define MAIN _main
+#else
+#define MAIN main
+#endif
+
+//#define DEBUG
+
+#ifdef DEBUG
+#define LOG_LEVEL RTE_LOG_DEBUG
+#define LOG_DEBUG(log_type, fmt, args...) do {	\
+	RTE_LOG(DEBUG, log_type, fmt, ##args);		\
+} while (0)
+#else
+#define LOG_LEVEL RTE_LOG_INFO
+#define LOG_DEBUG(log_type, fmt, args...) do{} while(0)
+#endif
+
+/* Macros for printing using RTE_LOG */
+#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
+#define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER2
+#define RTE_LOGTYPE_VHOST_PORT   RTE_LOGTYPE_USER3
+
+/*
+ * Device linked list structure for data path.
+ */
+struct virtio_net_data_ll
+{
+	struct virtio_net			*dev;	/* Pointer to device created by configuration core. */
+	struct virtio_net_data_ll	*next;  /* Pointer to next device in linked list. */
+};
+
+/*
+ * Structure containing data core specific information.
+ */
+struct lcore_ll_info
+{
+	struct virtio_net_data_ll	*ll_root_free; 		/* Pointer to head in free linked list. */
+	struct virtio_net_data_ll	*ll_root_used;		/* Pointer to head of used linked list. */
+	uint32_t 					device_num;			/* Number of devices on lcore. */
+	volatile uint8_t			dev_removal_flag;	/* Flag to synchronize device removal. */
+};
+
+struct lcore_info
+{
+	struct lcore_ll_info	*lcore_ll;	/* Pointer to data core specific lcore_ll_info struct */
+};
+
+int MAIN(int argc, char **argv);
+#endif /* _MAIN_H_ */
diff --git a/lib/librte_vhost/vhost-net-cdev.c b/lib/librte_vhost/vhost-net-cdev.c
new file mode 100644
index 0000000..8cf806a
--- /dev/null
+++ b/lib/librte_vhost/vhost-net-cdev.c
@@ -0,0 +1,367 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <errno.h>
+#include <fuse/cuse_lowlevel.h>
+#include <linux/limits.h>
+#include <linux/vhost.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+
+#include "main.h"
+#include "vhost-net-cdev.h"
+
+#define FUSE_OPT_DUMMY 		"\0\0"
+#define FUSE_OPT_FORE 		"-f\0\0"
+#define FUSE_OPT_NOMULTI 	"-s\0\0"
+
+const uint32_t	default_major = 231;
+const uint32_t	default_minor = 1;
+const char		cuse_device_name[]	= "/dev/cuse";
+const char		default_cdev[] = "vhost-net";
+
+static struct fuse_session			*session;
+static struct vhost_net_device_ops	const *ops;
+
+/*
+ * Returns vhost_device_ctx from given fuse_req_t. The index is populated later when
+ * the device is added to the device linked list.
+ */
+static struct vhost_device_ctx
+fuse_req_to_vhost_ctx(fuse_req_t req, struct fuse_file_info *fi)
+{
+	struct vhost_device_ctx ctx;
+	struct fuse_ctx const *const req_ctx = fuse_req_ctx(req);
+
+	ctx.pid = req_ctx->pid;
+	ctx.fh = fi->fh;
+
+	return ctx;
+}
+
+/*
+ * When the device is created in QEMU it gets initialised here and added to the device linked list.
+ */
+static void
+vhost_net_open(fuse_req_t req, struct fuse_file_info *fi)
+{
+	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
+	int err = 0;
+
+	err = ops->new_device(ctx);
+	if (err == -1) {
+		fuse_reply_err(req, EPERM);
+		return;
+	}
+
+	fi->fh = err;
+
+	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device configuration started\n", fi->fh);
+	fuse_reply_open(req, fi);
+}
+
+/*
+ * When QEMU is shutdown or killed the device gets released.
+ */
+static void
+vhost_net_release(fuse_req_t req, struct fuse_file_info *fi)
+{
+	int err = 0;
+	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
+
+	ops->destroy_device(ctx);
+	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device released\n", ctx.fh);
+	fuse_reply_err(req, err);
+}
+
+/*
+ * Boilerplate code for CUSE IOCTL
+ * Implicit arguments: ctx, req, result.
+ */
+#define VHOST_IOCTL(func) do {								\
+	result = (func)(ctx);									\
+	fuse_reply_ioctl(req, result, NULL, 0);					\
+} while(0)													\
+
+/*
+ * Boilerplate IOCTL RETRY
+ * Implicit arguments: req.
+ */
+#define VHOST_IOCTL_RETRY(size_r, size_w) do {									\
+	struct iovec iov_r = { arg, (size_r) };										\
+	struct iovec iov_w = { arg, (size_w) };										\
+	fuse_reply_ioctl_retry(req, &iov_r, (size_r)?1:0, &iov_w, (size_w)?1:0);	\
+} while(0)																		\
+
+/*
+ * Boilerplate code for CUSE Read IOCTL
+ * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
+ */
+#define VHOST_IOCTL_R(type, var, func) do {				\
+	if (!in_bufsz) {									\
+		VHOST_IOCTL_RETRY(sizeof(type), 0);				\
+	} else {											\
+		(var) = *(const type * ) in_buf;				\
+		result = func(ctx, &(var));						\
+		fuse_reply_ioctl(req, result, NULL, 0);			\
+	}													\
+} while(0)												\
+
+/*
+ *	Boilerplate code for CUSE Write IOCTL
+ * Implicit arguments: ctx, req, result, out_bufsz.
+ */
+#define	VHOST_IOCTL_W(type, var, func) do {						\
+	if (!out_bufsz) {											\
+		VHOST_IOCTL_RETRY(0, sizeof(type));						\
+	} else {													\
+		result = (func)(ctx, &(var));							\
+		fuse_reply_ioctl(req, result, &(var), sizeof(type));	\
+	}															\
+} while(0)														\
+
+/*
+ * Boilerplate code for CUSE Read/Write IOCTL
+ * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
+ */
+#define VHOST_IOCTL_RW(type1, var1, type2, var2, func) do {			\
+	if (!in_bufsz) {												\
+		VHOST_IOCTL_RETRY(sizeof(type1), sizeof(type2));			\
+	} else {														\
+		(var1) = *(const type1* ) (in_buf);							\
+		result = (func)(ctx, (var1), &(var2));						\
+		fuse_reply_ioctl(req, result, &(var2), sizeof(type2));		\
+	}																\
+} while(0)															\
+
+/*
+ * The IOCTLs are handled using CUSE/FUSE in userspace. Depending on
+ * the type of IOCTL a buffer is requested to read or to write. This
+ * request is handled by FUSE and the buffer is then given to CUSE.
+ */
+static void
+vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
+		struct fuse_file_info *fi, __rte_unused unsigned flags,
+		const void *in_buf, size_t in_bufsz, size_t out_bufsz)
+{
+	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
+	struct vhost_vring_file file;
+	struct vhost_vring_state state;
+	struct vhost_vring_addr addr;
+	uint64_t features;
+	uint32_t index;
+	int result = 0;
+
+	switch(cmd)
+	{
+		case VHOST_NET_SET_BACKEND:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_NET_SET_BACKEND\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_backend);
+			break;
+
+		case VHOST_GET_FEATURES:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_FEATURES\n", ctx.fh);
+			VHOST_IOCTL_W(uint64_t, features, ops->get_features);
+			break;
+
+		case VHOST_SET_FEATURES:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_FEATURES\n", ctx.fh);
+			VHOST_IOCTL_R(uint64_t, features, ops->set_features);
+			break;
+
+		case VHOST_RESET_OWNER:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_RESET_OWNER\n", ctx.fh);
+			VHOST_IOCTL(ops->reset_owner);
+			break;
+
+		case VHOST_SET_OWNER:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_OWNER\n", ctx.fh);
+			VHOST_IOCTL(ops->set_owner);
+			break;
+
+		case VHOST_SET_MEM_TABLE:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_MEM_TABLE\n", ctx.fh);
+			static struct vhost_memory mem_temp;
+
+			switch(in_bufsz){
+				case 0:
+					VHOST_IOCTL_RETRY(sizeof(struct vhost_memory), 0);
+					break;
+
+				case sizeof(struct vhost_memory):
+					mem_temp = *(const struct vhost_memory *) in_buf;
+
+					if (mem_temp.nregions > 0) {
+						VHOST_IOCTL_RETRY(sizeof(struct vhost_memory) + (sizeof(struct vhost_memory_region) * mem_temp.nregions), 0);
+					} else {
+						result = -1;
+						fuse_reply_ioctl(req, result, NULL, 0);
+					}
+					break;
+
+				default:
+					result = ops->set_mem_table(ctx, in_buf, mem_temp.nregions);
+					if (result)
+						fuse_reply_err(req, EINVAL);
+					else
+						fuse_reply_ioctl(req, result, NULL, 0);
+
+			}
+
+			break;
+
+		case VHOST_SET_VRING_NUM:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_NUM\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_num);
+			break;
+
+		case VHOST_SET_VRING_BASE:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_BASE\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_base);
+			break;
+
+		case VHOST_GET_VRING_BASE:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_VRING_BASE\n", ctx.fh);
+			VHOST_IOCTL_RW(uint32_t, index, struct vhost_vring_state, state, ops->get_vring_base);
+			break;
+
+		case VHOST_SET_VRING_ADDR:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_ADDR\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_addr, addr, ops->set_vring_addr);
+			break;
+
+		case VHOST_SET_VRING_KICK:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_KICK\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_kick);
+			break;
+
+		case VHOST_SET_VRING_CALL:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_CALL\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_call);
+			break;
+
+		default:
+			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") IOCTL: DOESN NOT EXIST\n", ctx.fh);
+			result = -1;
+			fuse_reply_ioctl(req, result, NULL, 0);
+	}
+
+	if (result < 0) {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: FAIL\n", ctx.fh);
+	} else {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: SUCCESS\n", ctx.fh);
+	}
+}
+
+/*
+ * Structure handling open, release and ioctl function pointers is populated.
+ */
+static const struct cuse_lowlevel_ops vhost_net_ops = {
+	.open		= vhost_net_open,
+	.release	= vhost_net_release,
+	.ioctl		= vhost_net_ioctl,
+};
+
+/*
+ * cuse_info is populated and used to register the cuse device. vhost_net_device_ops are
+ * also passed when the device is registered in main.c.
+ */
+int
+register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const pops)
+{
+	struct cuse_info cuse_info;
+	char device_name[PATH_MAX] = "";
+	char char_device_name[PATH_MAX] = "";
+	const char *device_argv[] = { device_name };
+
+	char fuse_opt_dummy[] = FUSE_OPT_DUMMY;
+	char fuse_opt_fore[] = FUSE_OPT_FORE;
+	char fuse_opt_nomulti[] = FUSE_OPT_NOMULTI;
+	char *fuse_argv[] = {fuse_opt_dummy, fuse_opt_fore, fuse_opt_nomulti};
+
+	if (access(cuse_device_name, R_OK | W_OK) < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s can't be accessed, maybe not exist\n", cuse_device_name);
+		return -1;
+	}
+
+	/*
+	 * The device name is created. This is passed to QEMU so that it can register
+	 * the device with our application. The index allows us to have multiple instances
+	 * of userspace vhost which we can then add devices to separately.
+	 */
+	if (strncmp(base_name, default_cdev, PATH_MAX)!=0) {
+		snprintf(device_name, PATH_MAX, "DEVNAME=%s-%d", base_name, index);
+		snprintf(char_device_name, PATH_MAX, "/dev/%s-%d", base_name, index);
+	} else {
+		snprintf(device_name, PATH_MAX, "DEVNAME=%s", base_name);
+		snprintf(char_device_name, PATH_MAX, "/dev/%s", base_name);
+	}
+
+	/* Check if device already exists. */
+	if (access(char_device_name, F_OK) != -1) {
+		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s already exists\n", char_device_name);
+		return -1;
+	}
+
+	memset(&cuse_info, 0, sizeof(cuse_info));
+	cuse_info.dev_major = default_major;
+	cuse_info.dev_minor = default_minor + index;
+	cuse_info.dev_info_argc = 1;
+	cuse_info.dev_info_argv = device_argv;
+	cuse_info.flags = CUSE_UNRESTRICTED_IOCTL;
+
+	ops = pops;
+
+	session = cuse_lowlevel_setup(3, fuse_argv,
+				&cuse_info, &vhost_net_ops, 0, NULL);
+	if (session == NULL)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * The CUSE session is launched allowing the application to receive open, release and ioctl calls.
+ */
+int
+start_cuse_session_loop(void)
+{
+	fuse_session_loop(session);
+
+	return 0;
+}
diff --git a/lib/librte_vhost/vhost-net-cdev.h b/lib/librte_vhost/vhost-net-cdev.h
new file mode 100644
index 0000000..575daa9
--- /dev/null
+++ b/lib/librte_vhost/vhost-net-cdev.h
@@ -0,0 +1,83 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _VHOST_NET_CDEV_H_
+#define _VHOST_NET_CDEV_H_
+
+#include <linux/vhost.h>
+
+struct vhost_memory;
+struct vhost_vring_state;
+struct vhost_vring_addr;
+struct vhost_vring_file;
+
+/*
+ * Structure used to identify device context.
+ */
+struct vhost_device_ctx
+{
+	pid_t		pid;	/* PID of process calling the IOCTL. */
+	uint64_t 	fh;		/* Populated with fi->fh to track the device index. */
+};
+
+/*
+ * Structure contains function pointers to be defined in virtio-net.c. These
+ * functions are called in CUSE context and are used to configure devices.
+ */
+struct vhost_net_device_ops {
+	int (* new_device) 		(struct vhost_device_ctx);
+	void (* destroy_device) (struct vhost_device_ctx);
+
+	int (* get_features) 	(struct vhost_device_ctx, uint64_t *);
+	int (* set_features) 	(struct vhost_device_ctx, uint64_t *);
+
+	int (* set_mem_table) 	(struct vhost_device_ctx, const void *, uint32_t);
+
+	int (* set_vring_num) 	(struct vhost_device_ctx, struct vhost_vring_state *);
+	int (* set_vring_addr) 	(struct vhost_device_ctx, struct vhost_vring_addr *);
+	int (* set_vring_base) 	(struct vhost_device_ctx, struct vhost_vring_state *);
+	int (* get_vring_base) 	(struct vhost_device_ctx, uint32_t, struct vhost_vring_state *);
+
+	int (* set_vring_kick) 	(struct vhost_device_ctx, struct vhost_vring_file *);
+	int (* set_vring_call) 	(struct vhost_device_ctx, struct vhost_vring_file *);
+
+	int (* set_backend) 	(struct vhost_device_ctx, struct vhost_vring_file *);
+
+	int (* set_owner) 		(struct vhost_device_ctx);
+	int (* reset_owner) 	(struct vhost_device_ctx);
+};
+
+int register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const);
+int start_cuse_session_loop(void);
+
+#endif /* _VHOST_NET_CDEV_H_ */
diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
new file mode 100644
index 0000000..5e659c7
--- /dev/null
+++ b/lib/librte_vhost/virtio-net.c
@@ -0,0 +1,1165 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <dirent.h>
+#include <fuse/cuse_lowlevel.h>
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <sys/eventfd.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+#include <rte_memory.h>
+
+#include "main.h"
+#include "virtio-net.h"
+#include "vhost-net-cdev.h"
+#include "eventfd_link/eventfd_link.h"
+
+const char eventfd_cdev[] = "/dev/eventfd-link";
+
+extern uint32_t num_devices;
+static uint32_t num_cur_devices = 0;
+
+/* device ops to add/remove device to data core. */
+static struct virtio_net_device_ops const * notify_ops;
+/* Root address of the linked list in the configuration core. */
+static struct virtio_net_config_ll			*ll_root = NULL;
+
+/* Features supported by this application. RX merge buffers are disabled by default. */
+uint64_t VHOST_FEATURES = (0ULL << VIRTIO_NET_F_MRG_RXBUF);
+
+/* Line size for reading maps file. */
+const uint32_t BUFSIZE = PATH_MAX;
+
+/* Size of prot char array in procmap. */
+#define PROT_SZ 5
+
+/* Number of elements in procmap struct. */
+#define PROCMAP_SZ 8
+
+/* Structure containing information gathered from maps file. */
+struct procmap
+{
+	uint64_t	va_start;			/* Start virtual address in file. */
+	uint64_t	len;				/* Size of file. */
+	uint64_t	pgoff;				/* Not used. */
+	uint32_t	maj;				/* Not used. */
+	uint32_t	min;				/* Not used. */
+	uint32_t	ino;				/* Not used. */
+	char		prot[PROT_SZ];		/* Not used. */
+	char		fname[PATH_MAX];	/* File name. */
+};
+
+/*
+ * Converts QEMU virtual address to Vhost virtual address. This function is used
+ * to convert the ring addresses to our address space.
+ */
+static uint64_t
+qva_to_vva(struct virtio_net *dev, uint64_t qemu_va)
+{
+	struct virtio_memory_regions *region;
+	uint64_t vhost_va = 0;
+	uint32_t regionidx = 0;
+
+	/* Find the region where the address lives. */
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		region = &dev->mem->regions[regionidx];
+		if ((qemu_va >= region->userspace_address) &&
+				(qemu_va <= region->userspace_address +
+			 	region->memory_size)) {
+			vhost_va = dev->mem->mapped_address + qemu_va - dev->mem->base_address;
+			break;
+		}
+	}
+	return vhost_va;
+}
+
+/*
+ * Locate the file containing QEMU's memory space and map it to our address space.
+ */
+static int
+host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, uint64_t addr)
+{
+	struct dirent *dptr = NULL;
+	struct procmap procmap;
+	DIR *dp = NULL;
+	int fd;
+	int i;
+	char memfile[PATH_MAX];
+	char mapfile[PATH_MAX];
+	char procdir[PATH_MAX];
+	char resolved_path[PATH_MAX];
+	FILE		*fmap;
+	void		*map;
+	uint8_t 	found = 0;
+	char 		line[BUFSIZE];
+	char dlm[] = "-   :   ";
+	char *str, *sp, *in[PROCMAP_SZ];
+	char *end = NULL;
+
+	/* Path where mem files are located. */
+	snprintf (procdir, PATH_MAX, "/proc/%u/fd/", pid);
+	/* Maps file used to locate mem file. */
+	snprintf (mapfile, PATH_MAX, "/proc/%u/maps", pid);
+
+	fmap = fopen(mapfile, "r");
+	if (fmap == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open maps file for pid %d\n", dev->device_fh, pid);
+		return -1;
+	}
+
+	/* Read through maps file until we find out base_address. */
+	while (fgets(line, BUFSIZE, fmap) != 0) {
+		str = line;
+		errno = 0;
+		/* Split line in to fields. */
+		for (i = 0; i < PROCMAP_SZ; i++) {
+			if (((in[i] = strtok_r(str, &dlm[i], &sp)) == NULL) || (errno != 0)) {
+				fclose(fmap);
+				return -1;
+			}
+			str = NULL;
+		}
+
+		/* Convert/Copy each field as needed. */
+		procmap.va_start = strtoull(in[0], &end, 16);
+		if ((in[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.len = strtoull(in[1], &end, 16);
+		if ((in[1] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.pgoff = strtoull(in[3], &end, 16);
+		if ((in[3] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.maj = strtoul(in[4], &end, 16);
+		if ((in[4] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.min = strtoul(in[5], &end, 16);
+		if ((in[5] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.ino = strtoul(in[6], &end, 16);
+		if ((in[6] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		memcpy(&procmap.prot, in[2], PROT_SZ);
+		memcpy(&procmap.fname, in[7], PATH_MAX);
+
+		if (procmap.va_start == addr) {
+			procmap.len = procmap.len - procmap.va_start;
+			found = 1;
+			break;
+		}
+	}
+	fclose(fmap);
+
+	if (!found) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find memory file in pid %d maps file\n", dev->device_fh, pid);
+		return -1;
+	}
+
+	/* Find the guest memory file among the process fds. */
+	dp = opendir(procdir);
+	if (dp == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Cannot open pid %d process directory \n", dev->device_fh, pid);
+		return -1;
+
+	}
+
+	found = 0;
+
+	/* Read the fd directory contents. */
+	while (NULL != (dptr = readdir(dp))) {
+		snprintf (memfile, PATH_MAX, "/proc/%u/fd/%s", pid, dptr->d_name);
+	    realpath(memfile, resolved_path);
+		if (resolved_path == NULL) {
+			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to resolve fd directory\n", dev->device_fh);
+			closedir(dp);
+			return -1;
+		}
+		if (strncmp(resolved_path, procmap.fname,
+			strnlen(procmap.fname, PATH_MAX)) == 0) {
+			found = 1;
+			break;
+		}
+	}
+
+	closedir(dp);
+
+	if (found == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find memory file for pid %d\n", dev->device_fh, pid);
+		return -1;
+	}
+	/* Open the shared memory file and map the memory into this process. */
+	fd = open(memfile, O_RDWR);
+
+	if (fd == -1) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open %s for pid %d\n", dev->device_fh, memfile, pid);
+		return -1;
+	}
+
+	map = mmap(0, (size_t)procmap.len, PROT_READ|PROT_WRITE , MAP_POPULATE|MAP_SHARED, fd, 0);
+	close (fd);
+
+	if (map == MAP_FAILED) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Error mapping the file %s for pid %d\n",  dev->device_fh, memfile, pid);
+		return -1;
+	}
+
+	/* Store the memory address and size in the device data structure */
+	mem->mapped_address = (uint64_t)(uintptr_t)map;
+	mem->mapped_size = procmap.len;
+
+	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mem File: %s->%s - Size: %llu - VA: %p\n", dev->device_fh,
+		memfile, resolved_path, (long long unsigned)mem->mapped_size, map);
+
+	return 0;
+}
+
+/*
+ * Retrieves an entry from the devices configuration linked list.
+ */
+static struct virtio_net_config_ll *
+get_config_ll_entry(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev = ll_root;
+
+	/* Loop through linked list until the device_fh is found. */
+	while (ll_dev != NULL) {
+		if (ll_dev->dev.device_fh == ctx.fh)
+			return ll_dev;
+		ll_dev = ll_dev->next;
+	}
+
+	return NULL;
+}
+
+/*
+ * Searches the configuration core linked list and retrieves the device if it exists.
+ */
+static struct virtio_net *
+get_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev;
+
+	ll_dev = get_config_ll_entry(ctx);
+
+	/* If a matching entry is found in the linked list, return the device in that entry. */
+	if (ll_dev) {
+		return &ll_dev->dev;
+	}
+
+	RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Device not found in linked list.\n", ctx.fh);
+	return NULL;
+}
+
+/*
+ * Add entry containing a device to the device configuration linked list.
+ */
+static void
+add_config_ll_entry(struct virtio_net_config_ll *new_ll_dev)
+{
+	struct virtio_net_config_ll *ll_dev = ll_root;
+
+	/* If ll_dev == NULL then this is the first device so go to else */
+	if (ll_dev) {
+		/* If the 1st device_fh != 0 then we insert our device here. */
+		if (ll_dev->dev.device_fh != 0)	{
+			new_ll_dev->dev.device_fh = 0;
+			new_ll_dev->next = ll_dev;
+			ll_root = new_ll_dev;
+		} else {
+			/* Increment through the ll until we find un unused device_fh. Insert the device at that entry*/
+			while ((ll_dev->next != NULL) && (ll_dev->dev.device_fh == (ll_dev->next->dev.device_fh - 1)))
+				ll_dev = ll_dev->next;
+
+			new_ll_dev->dev.device_fh = ll_dev->dev.device_fh + 1;
+			new_ll_dev->next = ll_dev->next;
+			ll_dev->next = new_ll_dev;
+		}
+	} else {
+		ll_root = new_ll_dev;
+		ll_root->dev.device_fh = 0;
+	}
+
+}
+
+/*
+ * Unmap any memory, close any file descriptors and free any memory owned by a device.
+ */
+static void
+cleanup_device(struct virtio_net *dev)
+{
+	/* Unmap QEMU memory file if mapped. */
+	if (dev->mem) {
+		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
+		if (dev->mem->regions_hpa)
+			free(dev->mem->regions_hpa);
+		free(dev->mem);
+	}
+
+	/* Close any event notifiers opened by device. */
+	if (dev->virtqueue[VIRTIO_RXQ]->callfd)
+		close((int)dev->virtqueue[VIRTIO_RXQ]->callfd);
+	if (dev->virtqueue[VIRTIO_RXQ]->kickfd)
+		close((int)dev->virtqueue[VIRTIO_RXQ]->kickfd);
+	if (dev->virtqueue[VIRTIO_TXQ]->callfd)
+		close((int)dev->virtqueue[VIRTIO_TXQ]->callfd);
+	if (dev->virtqueue[VIRTIO_TXQ]->kickfd)
+		close((int)dev->virtqueue[VIRTIO_TXQ]->kickfd);
+}
+
+/*
+ * Release virtqueues and device memory.
+ */
+static void
+free_device(struct virtio_net_config_ll *ll_dev)
+{
+	/* Free any malloc'd memory */
+	free(ll_dev->dev.virtqueue[VIRTIO_RXQ]);
+	free(ll_dev->dev.virtqueue[VIRTIO_TXQ]);
+	free(ll_dev);
+}
+/*
+ * Remove an entry from the device configuration linked list.
+ */
+static struct virtio_net_config_ll *
+rm_config_ll_entry(struct virtio_net_config_ll *ll_dev, struct virtio_net_config_ll *ll_dev_last)
+{
+	/* First remove the device and then clean it up. */
+	if (ll_dev == ll_root) {
+		ll_root = ll_dev->next;
+		cleanup_device(&ll_dev->dev);
+		free_device(ll_dev);
+		return ll_root;
+	} else {
+		if (likely(ll_dev_last != NULL)) {
+			ll_dev_last->next = ll_dev->next;
+			cleanup_device(&ll_dev->dev);
+			free_device(ll_dev);
+			return ll_dev_last->next;
+		} else {
+			cleanup_device(&ll_dev->dev);
+			free_device(ll_dev);
+			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry from config_ll failed\n");
+			return NULL;
+		}
+	}
+}
+
+/*
+ *  Initialise all variables in device structure.
+ */
+static void
+init_device(struct virtio_net *dev)
+{
+	uint64_t vq_offset;
+
+	/* Virtqueues have already been malloced so we don't want to set them to NULL. */
+	vq_offset = offsetof(struct virtio_net, mem);
+
+	/* Set everything to 0. */
+	memset((void*)(uintptr_t)((uint64_t)(uintptr_t)dev + vq_offset), 0,
+		(sizeof(struct virtio_net) - (size_t)vq_offset));
+	memset(dev->virtqueue[VIRTIO_RXQ], 0, sizeof(struct vhost_virtqueue));
+	memset(dev->virtqueue[VIRTIO_TXQ], 0, sizeof(struct vhost_virtqueue));
+
+	/* Backends are set to -1 indicating an inactive device. */
+	dev->virtqueue[VIRTIO_RXQ]->backend = VIRTIO_DEV_STOPPED;
+	dev->virtqueue[VIRTIO_TXQ]->backend = VIRTIO_DEV_STOPPED;
+}
+
+/*
+ * Function is called from the CUSE open function. The device structure is
+ * initialised and a new entry is added to the device configuration linked
+ * list.
+ */
+static int
+new_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *new_ll_dev;
+	struct vhost_virtqueue *virtqueue_rx, *virtqueue_tx;
+
+	/*check the number of devices in the system*/
+	if (num_cur_devices == num_devices) {
+		RTE_LOG(ERR, VHOST_CONFIG, "() Max num devices (%u) exceeded\n", num_devices);
+		return -1;
+	}
+
+	/* Setup device and virtqueues. */
+	new_ll_dev = malloc(sizeof(struct virtio_net_config_ll));
+	if (new_ll_dev == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev.\n", ctx.fh);
+		return -1;
+	}
+
+	virtqueue_rx = malloc(sizeof(struct vhost_virtqueue));
+	if (virtqueue_rx == NULL) {
+		free(new_ll_dev);
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_rx.\n", ctx.fh);
+		return -1;
+	}
+
+	virtqueue_tx = malloc(sizeof(struct vhost_virtqueue));
+	if (virtqueue_tx == NULL) {
+		free(virtqueue_rx);
+		free(new_ll_dev);
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_tx.\n", ctx.fh);
+		return -1;
+	}
+
+	new_ll_dev->dev.virtqueue[VIRTIO_RXQ] = virtqueue_rx;
+	new_ll_dev->dev.virtqueue[VIRTIO_TXQ] = virtqueue_tx;
+
+	/* Initialise device and virtqueues. */
+	init_device(&new_ll_dev->dev);
+
+	new_ll_dev->next = NULL;
+
+	/* Add entry to device configuration linked list. */
+	add_config_ll_entry(new_ll_dev);
+
+	/*increment the number of devices in the system*/
+	num_cur_devices++;
+
+	return new_ll_dev->dev.device_fh;
+}
+
+/*
+ * Function is called from the CUSE release function. This function will cleanup
+ * the device and remove it from device configuration linked list.
+ */
+static void
+destroy_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev_cur_ctx, *ll_dev_last = NULL;
+	struct virtio_net_config_ll *ll_dev_cur = ll_root;
+
+	/* Find the linked list entry for the device to be removed. */
+	ll_dev_cur_ctx = get_config_ll_entry(ctx);
+	while (ll_dev_cur != NULL) {
+		/* If the device is found or a device that doesn't exist is found then it is removed. */
+		if (ll_dev_cur == ll_dev_cur_ctx) {
+			/*
+			 * If the device is running on a data core then call the function to remove it from
+			 * the data core.
+			 */
+			if ((ll_dev_cur->dev.flags & VIRTIO_DEV_RUNNING))
+				notify_ops->destroy_device(&(ll_dev_cur->dev));
+			ll_dev_cur = rm_config_ll_entry(ll_dev_cur, ll_dev_last);
+		} else {
+			ll_dev_last = ll_dev_cur;
+			ll_dev_cur = ll_dev_cur->next;
+		}
+	}
+
+	/*decrement the number of devices in the system*/
+	num_cur_devices--;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_OWNER
+ * This function just returns success at the moment unless the device hasn't been initialised.
+ */
+static int
+set_owner(struct vhost_device_ctx ctx)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_RESET_OWNER
+ */
+static int
+reset_owner(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev;
+
+	ll_dev = get_config_ll_entry(ctx);
+
+	cleanup_device(&ll_dev->dev);
+	init_device(&ll_dev->dev);
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_GET_FEATURES
+ * The features that we support are requested.
+ */
+static int
+get_features(struct vhost_device_ctx ctx, uint64_t *pu)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* Send our supported features. */
+	*pu = VHOST_FEATURES;
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_FEATURES
+ * We receive the negotiated set of features supported by us and the virtio device.
+ */
+static int
+set_features(struct vhost_device_ctx ctx, uint64_t *pu)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+	if (*pu & ~VHOST_FEATURES)
+		return -1;
+
+	/* Store the negotiated feature list for the device. */
+	dev->features = *pu;
+
+	/* Set the vhost_hlen depending on if VIRTIO_NET_F_MRG_RXBUF is set. */
+	if (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers enabled\n", dev->device_fh);
+		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	} else {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers disabled\n", dev->device_fh);
+		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
+		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
+	}
+	return 0;
+}
+
+/*
+ * Calculate the region count of physical continous regions for one particular
+ * region of whose vhost virtual address is continous. The particular region
+ * start from vva_start, with size of 'size' in argument.
+ */
+static uint32_t check_hpa_regions(uint64_t vva_start, uint64_t size)
+{
+	uint32_t i, nregions = 0, page_size = PAGE_SIZE;
+	uint64_t cur_phys_addr = 0, next_phys_addr = 0;
+	if (vva_start % page_size) {
+		LOG_DEBUG(VHOST_CONFIG,
+			"in check_countinous: vva start(%p) mod page_size(%d) "
+			"has remainder\n",
+			(void *)(uintptr_t)vva_start, page_size);
+		return 0;
+	}
+	if (size % page_size) {
+		LOG_DEBUG(VHOST_CONFIG,
+			"in check_countinous: "
+			"size((%"PRIu64")) mod page_size(%d) has remainder\n",
+			size, page_size);
+		return 0;
+	}
+	for (i = 0; i < size - page_size; i = i + page_size) {
+		cur_phys_addr
+			= rte_mem_virt2phy((void *)(uintptr_t)(vva_start + i));
+		next_phys_addr = rte_mem_virt2phy(
+			(void *)(uintptr_t)(vva_start + i + page_size));
+		if ((cur_phys_addr + page_size) != next_phys_addr) {
+			++nregions;
+			LOG_DEBUG(VHOST_CONFIG,
+				"in check_continuous: hva addr:(%p) is not "
+				"continuous with hva addr:(%p), diff:%d\n",
+				(void *)(uintptr_t)(vva_start + (uint64_t)i),
+				(void *)(uintptr_t)(vva_start + (uint64_t)i
+				+ page_size), page_size);
+			LOG_DEBUG(VHOST_CONFIG,
+				"in check_continuous: hpa addr:(%p) is not "
+				"continuous with hpa addr:(%p), "
+				"diff:(%"PRIu64")\n",
+				(void *)(uintptr_t)cur_phys_addr,
+				(void *)(uintptr_t)next_phys_addr,
+				(next_phys_addr-cur_phys_addr));
+		}
+	}
+	return nregions;
+}
+
+/*
+ * Divide each region whose vhost virtual address is continous into a few
+ * sub-regions, make sure the physical address within each sub-region are
+ * continous. And fill offset(to GPA) and size etc. information of each
+ * sub-region into regions_hpa.
+ */
+static uint32_t fill_hpa_memory_regions(void *memory)
+{
+	uint32_t regionidx, regionidx_hpa = 0, i, k, page_size = PAGE_SIZE;
+	uint64_t cur_phys_addr = 0, next_phys_addr = 0, vva_start;
+	struct virtio_memory *virtio_memory = (struct virtio_memory *)memory;
+	struct virtio_memory_regions_hpa *mem_region_hpa
+		= virtio_memory->regions_hpa;
+
+	if (mem_region_hpa == NULL)
+		return 0;
+
+	for (regionidx = 0; regionidx < virtio_memory->nregions; regionidx++) {
+		vva_start = virtio_memory->regions[regionidx].guest_phys_address
+			+ virtio_memory->regions[regionidx].address_offset;
+		mem_region_hpa[regionidx_hpa].guest_phys_address
+			= virtio_memory->regions[regionidx].guest_phys_address;
+		mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
+			rte_mem_virt2phy((void *)(uintptr_t)(vva_start))
+			- mem_region_hpa[regionidx_hpa].guest_phys_address;
+		LOG_DEBUG(VHOST_CONFIG,
+			"in fill_hpa_regions: guest phys addr start[%d]:(%p)\n",
+			regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].guest_phys_address));
+		LOG_DEBUG(VHOST_CONFIG,
+			"in fill_hpa_regions: host  phys addr start[%d]:(%p)\n",
+			regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
+		for (i = 0, k = 0;
+			i < virtio_memory->regions[regionidx].memory_size
+				- page_size;
+			i += page_size) {
+			cur_phys_addr = rte_mem_virt2phy(
+					(void *)(uintptr_t)(vva_start + i));
+			next_phys_addr = rte_mem_virt2phy(
+					(void *)(uintptr_t)(vva_start
+					+ i + page_size));
+			if ((cur_phys_addr + page_size) != next_phys_addr) {
+				mem_region_hpa[regionidx_hpa].guest_phys_address_end =
+					mem_region_hpa[regionidx_hpa].guest_phys_address
+					+ k + page_size;
+				mem_region_hpa[regionidx_hpa].memory_size
+					= k + page_size;
+				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest "
+					"phys addr end  [%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
+				LOG_DEBUG(VHOST_CONFIG,
+					"in fill_hpa_regions: guest phys addr "
+					"size [%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].memory_size));
+				mem_region_hpa[regionidx_hpa + 1].guest_phys_address
+					= mem_region_hpa[regionidx_hpa].guest_phys_address_end;
+				++regionidx_hpa;
+				mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
+					next_phys_addr
+					- mem_region_hpa[regionidx_hpa].guest_phys_address;
+				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest"
+					" phys addr start[%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].guest_phys_address));
+				LOG_DEBUG(VHOST_CONFIG,
+					"in fill_hpa_regions: host  phys addr "
+					"start[%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
+				k = 0;
+			} else {
+				k += page_size;
+			}
+		}
+		mem_region_hpa[regionidx_hpa].guest_phys_address_end
+			= mem_region_hpa[regionidx_hpa].guest_phys_address
+			+ k + page_size;
+		mem_region_hpa[regionidx_hpa].memory_size = k + page_size;
+		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr end  "
+			"[%d]:(%p)\n", regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
+		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr size "
+			"[%d]:(%p)\n", regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].memory_size));
+		++regionidx_hpa;
+	}
+	return regionidx_hpa;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_MEM_TABLE
+ * This function creates and populates the memory structure for the device. This includes
+ * storing offsets used to translate buffer addresses.
+ */
+static int
+set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_t nregions)
+{
+	struct virtio_net *dev;
+	struct vhost_memory_region *mem_regions;
+	struct virtio_memory *mem;
+	uint64_t size = offsetof(struct vhost_memory, regions);
+	uint32_t regionidx, valid_regions;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	if (dev->mem) {
+		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
+		free(dev->mem);
+	}
+
+	/* Malloc the memory structure depending on the number of regions. */
+	mem = calloc(1, sizeof(struct virtio_memory) + (sizeof(struct virtio_memory_regions) * nregions));
+	if (mem == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev->mem.\n", dev->device_fh);
+		return -1;
+	}
+
+	mem->nregions = nregions;
+
+	mem_regions = (void*)(uintptr_t)((uint64_t)(uintptr_t)mem_regions_addr + size);
+
+	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
+		/* Populate the region structure for each region. */
+		mem->regions[regionidx].guest_phys_address = mem_regions[regionidx].guest_phys_addr;
+		mem->regions[regionidx].guest_phys_address_end = mem->regions[regionidx].guest_phys_address +
+			mem_regions[regionidx].memory_size;
+		mem->regions[regionidx].memory_size = mem_regions[regionidx].memory_size;
+		mem->regions[regionidx].userspace_address = mem_regions[regionidx].userspace_addr;
+
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") REGION: %u - GPA: %p - QEMU VA: %p - SIZE (%"PRIu64")\n", dev->device_fh,
+				regionidx, (void*)(uintptr_t)mem->regions[regionidx].guest_phys_address,
+				(void*)(uintptr_t)mem->regions[regionidx].userspace_address,
+				mem->regions[regionidx].memory_size);
+
+		/*set the base address mapping*/
+		if (mem->regions[regionidx].guest_phys_address == 0x0) {
+			mem->base_address = mem->regions[regionidx].userspace_address;
+			/* Map VM memory file */
+			if (host_memory_map(dev, mem, ctx.pid, mem->base_address) != 0) {
+				free(mem);
+				return -1;
+			}
+		}
+	}
+
+	/* Check that we have a valid base address. */
+	if (mem->base_address == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find base address of qemu memory file.\n", dev->device_fh);
+		free(mem);
+		return -1;
+	}
+
+	/* Check if all of our regions have valid mappings. Usually one does not exist in the QEMU memory file. */
+	valid_regions = mem->nregions;
+	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
+		if ((mem->regions[regionidx].userspace_address < mem->base_address) ||
+			(mem->regions[regionidx].userspace_address > (mem->base_address + mem->mapped_size)))
+				valid_regions--;
+	}
+
+	/* If a region does not have a valid mapping we rebuild our memory struct to contain only valid entries. */
+	if (valid_regions != mem->nregions) {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Not all memory regions exist in the QEMU mem file. Re-populating mem structure\n",
+			dev->device_fh);
+
+		/* Re-populate the memory structure with only valid regions. Invalid regions are over-written with memmove. */
+		valid_regions = 0;
+
+		for (regionidx = mem->nregions; 0 != regionidx--;) {
+			if ((mem->regions[regionidx].userspace_address < mem->base_address) ||
+					(mem->regions[regionidx].userspace_address > (mem->base_address + mem->mapped_size))) {
+				memmove(&mem->regions[regionidx], &mem->regions[regionidx + 1],
+					sizeof(struct virtio_memory_regions) * valid_regions);
+			} else {
+				valid_regions++;
+			}
+		}
+	}
+	mem->nregions = valid_regions;
+	mem->nregions_hpa = mem->nregions;
+	dev->mem = mem;
+
+	/*
+	 * Calculate the address offset for each region. This offset is used to identify the vhost virtual address
+	 * corresponding to a QEMU guest physical address.
+	 */
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		dev->mem->regions[regionidx].address_offset = dev->mem->regions[regionidx].userspace_address - dev->mem->base_address
+			+ dev->mem->mapped_address - dev->mem->regions[regionidx].guest_phys_address;
+
+		dev->mem->nregions_hpa
+			+= check_hpa_regions(
+				dev->mem->regions[regionidx].guest_phys_address
+				+ dev->mem->regions[regionidx].address_offset,
+				dev->mem->regions[regionidx].memory_size);
+	}
+	if (dev->mem->regions_hpa != NULL) {
+		free(dev->mem->regions_hpa);
+		dev->mem->regions_hpa = NULL;
+	}
+
+	dev->mem->regions_hpa = (struct virtio_memory_regions_hpa *) calloc(1,
+		(sizeof(struct virtio_memory_regions_hpa)
+		* dev->mem->nregions_hpa));
+	if (dev->mem->regions_hpa == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for "
+			"dev->mem->regions_hpa.\n", dev->device_fh);
+		return -1;
+	}
+	if (fill_hpa_memory_regions(
+		(void *)dev->mem) != dev->mem->nregions_hpa) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"in set_mem_table: hpa memory regions number mismatch: "
+			"[%d]\n", dev->mem->nregions_hpa);
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_NUM
+ * The virtio device sends us the size of the descriptor ring.
+ */
+static int
+set_vring_num(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	dev->virtqueue[state->index]->size = state->num;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_ADDR
+ * The virtio device sends us the desc, used and avail ring addresses. This function
+ * then converts these to our address space.
+ */
+static int
+set_vring_addr(struct vhost_device_ctx ctx, struct vhost_vring_addr *addr)
+{
+	struct virtio_net *dev;
+	struct vhost_virtqueue *vq;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* addr->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	vq = dev->virtqueue[addr->index];
+
+	/* The addresses are converted from QEMU virtual to Vhost virtual. */
+	vq->desc = (struct vring_desc*)(uintptr_t)qva_to_vva(dev, addr->desc_user_addr);
+	if (vq->desc == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find descriptor ring address.\n", dev->device_fh);
+		return -1;
+	}
+
+	vq->avail = (struct vring_avail*)(uintptr_t)qva_to_vva(dev, addr->avail_user_addr);
+	if (vq->avail == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find available ring address.\n", dev->device_fh);
+		return -1;
+	}
+
+	vq->used = (struct vring_used*)(uintptr_t)qva_to_vva(dev, addr->used_user_addr);
+	if (vq->used == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find used ring address.\n", dev->device_fh);
+		return -1;
+	}
+
+	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address desc: %p\n", dev->device_fh, vq->desc);
+	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address avail: %p\n", dev->device_fh, vq->avail);
+	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address used: %p\n", dev->device_fh, vq->used);
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_BASE
+ * The virtio device sends us the available ring last used index.
+ */
+static int
+set_vring_base(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	dev->virtqueue[state->index]->last_used_idx = state->num;
+	dev->virtqueue[state->index]->last_used_idx_res = state->num;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_GET_VRING_BASE
+ * We send the virtio device our available ring last used index.
+ */
+static int
+get_vring_base(struct vhost_device_ctx ctx, uint32_t index, struct vhost_vring_state *state)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	state->index = index;
+	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	state->num = dev->virtqueue[state->index]->last_used_idx;
+
+	return 0;
+}
+
+/*
+ * This function uses the eventfd_link kernel module to copy an eventfd file descriptor
+ * provided by QEMU in to our process space.
+ */
+static int
+eventfd_copy(struct virtio_net *dev, struct eventfd_copy *eventfd_copy)
+{
+	int eventfd_link, ret;
+
+	/* Open the character device to the kernel module. */
+	eventfd_link = open(eventfd_cdev, O_RDWR);
+	if (eventfd_link < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") eventfd_link module is not loaded\n",  dev->device_fh);
+		return -1;
+	}
+
+	/* Call the IOCTL to copy the eventfd. */
+	ret = ioctl(eventfd_link, EVENTFD_COPY, eventfd_copy);
+	close(eventfd_link);
+
+	if (ret < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") EVENTFD_COPY ioctl failed\n",  dev->device_fh);
+		return -1;
+	}
+
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_CALL
+ * The virtio device sends an eventfd to interrupt the guest. This fd gets copied in
+ * to our process space.
+ */
+static int
+set_vring_call(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+	struct virtio_net *dev;
+	struct eventfd_copy	eventfd_kick;
+	struct vhost_virtqueue *vq;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	vq = dev->virtqueue[file->index];
+
+	if (vq->kickfd)
+		close((int)vq->kickfd);
+
+	/* Populate the eventfd_copy structure and call eventfd_copy. */
+	vq->kickfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+	eventfd_kick.source_fd = vq->kickfd;
+	eventfd_kick.target_fd = file->fd;
+	eventfd_kick.target_pid = ctx.pid;
+
+	if (eventfd_copy(dev, &eventfd_kick))
+		return -1;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_KICK
+ * The virtio device sends an eventfd that it can use to notify us. This fd gets copied in
+ * to our process space.
+ */
+static int
+set_vring_kick(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+	struct virtio_net *dev;
+	struct eventfd_copy eventfd_call;
+	struct vhost_virtqueue *vq;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	vq = dev->virtqueue[file->index];
+
+	if (vq->callfd)
+		close((int)vq->callfd);
+
+	/* Populate the eventfd_copy structure and call eventfd_copy. */
+	vq->callfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+	eventfd_call.source_fd = vq->callfd;
+	eventfd_call.target_fd = file->fd;
+	eventfd_call.target_pid = ctx.pid;
+
+	if (eventfd_copy(dev, &eventfd_call))
+        return -1;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_NET_SET_BACKEND
+ * To complete device initialisation when the virtio driver is loaded we are provided with a
+ * valid fd for a tap device (not used by us). If this happens then we can add the device to a
+ * data core. When the virtio driver is removed we get fd=-1. At that point we remove the device
+ * from the data core. The device will still exist in the device configuration linked list.
+ */
+static int
+set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL) {
+		return -1;
+	}
+
+	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	dev->virtqueue[file->index]->backend = file->fd;
+
+	/* If the device isn't already running and both backend fds are set we add the device. */
+	if (!(dev->flags & VIRTIO_DEV_RUNNING)) {
+		if (((int)dev->virtqueue[VIRTIO_TXQ]->backend != VIRTIO_DEV_STOPPED) &&
+			((int)dev->virtqueue[VIRTIO_RXQ]->backend != VIRTIO_DEV_STOPPED))
+			return notify_ops->new_device(dev);
+	/* Otherwise we remove it. */
+	} else
+		if (file->fd == VIRTIO_DEV_STOPPED) {
+			notify_ops->destroy_device(dev);
+		}
+	return 0;
+}
+
+/*
+ * Function pointers are set for the device operations to allow CUSE to call functions
+ * when an IOCTL, device_add or device_release is received.
+ */
+static const struct vhost_net_device_ops vhost_device_ops =
+{
+	.new_device = new_device,
+	.destroy_device = destroy_device,
+
+	.get_features = get_features,
+	.set_features = set_features,
+
+	.set_mem_table = set_mem_table,
+
+	.set_vring_num = set_vring_num,
+	.set_vring_addr = set_vring_addr,
+	.set_vring_base = set_vring_base,
+	.get_vring_base = get_vring_base,
+
+	.set_vring_kick = set_vring_kick,
+	.set_vring_call = set_vring_call,
+
+	.set_backend = set_backend,
+
+	.set_owner = set_owner,
+	.reset_owner = reset_owner,
+};
+
+/*
+ * Called by main to setup callbacks when registering CUSE device.
+ */
+struct vhost_net_device_ops const *
+get_virtio_net_callbacks(void)
+{
+	return &vhost_device_ops;
+}
+
+/*
+ * Register ops so that we can add/remove device to data core.
+ */
+int
+init_virtio_net(struct virtio_net_device_ops const * const ops)
+{
+	notify_ops = ops;
+
+	return 0;
+}
+
+/*
+ * Currently not used as we Ctrl+c to exit application.
+ */
+int
+deinit_virtio_net(void)
+{
+	return 0;
+}
diff --git a/lib/librte_vhost/virtio-net.h b/lib/librte_vhost/virtio-net.h
new file mode 100644
index 0000000..1a2f0dc
--- /dev/null
+++ b/lib/librte_vhost/virtio-net.h
@@ -0,0 +1,161 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _VIRTIO_NET_H_
+#define _VIRTIO_NET_H_
+
+/* Used to indicate that the device is running on a data core */
+#define VIRTIO_DEV_RUNNING 1
+
+/* Backend value set by guest. */
+#define VIRTIO_DEV_STOPPED -1
+
+#define PAGE_SIZE   4096
+
+/* Enum for virtqueue management. */
+enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
+
+#define BUF_VECTOR_MAX 256
+
+/*
+ * Structure contains buffer address, length and descriptor index
+ * from vring to do scatter RX.
+*/
+struct buf_vector {
+uint64_t buf_addr;
+uint32_t buf_len;
+uint32_t desc_idx;
+};
+
+/*
+ * Structure contains variables relevant to TX/RX virtqueues.
+ */
+struct vhost_virtqueue
+{
+	struct vring_desc	*desc;				/* Virtqueue descriptor ring. */
+	struct vring_avail	*avail;				/* Virtqueue available ring. */
+	struct vring_used	*used;				/* Virtqueue used ring. */
+	uint32_t			size;				/* Size of descriptor ring. */
+	uint32_t			backend;			/* Backend value to determine if device should started/stopped. */
+	uint16_t			vhost_hlen;			/* Vhost header length (varies depending on RX merge buffers. */
+	volatile uint16_t	last_used_idx;		/* Last index used on the available ring */
+	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
+	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
+	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
+	/* Used for scatter RX. */
+	struct buf_vector	buf_vec[BUF_VECTOR_MAX];
+} __rte_cache_aligned;
+
+/*
+ * Device structure contains all configuration information relating to the device.
+ */
+struct virtio_net
+{
+	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/* Contains all virtqueue information. */
+	struct virtio_memory 	*mem;						/* QEMU memory and memory region information. */
+	struct ether_addr 		mac_address;				/* Device MAC address (Obtained on first TX packet). */
+	uint64_t 				features;					/* Negotiated feature set. */
+	uint64_t 				device_fh;					/* device identifier. */
+	uint32_t 				vmdq_rx_q;					/* RX VMDQ queue number. */
+	uint32_t 				flags;						/* Device flags. Only used to check if device is running on data core. */
+	uint32_t 				vlan_tag;					/* Vlan tag for device. Currently set to device_id (0-63). */
+	uint16_t 				coreid;						/* Data core that the device is added to. */
+	volatile uint8_t 		ready;						/* A device is set as ready if the MAC address has been set. */
+	volatile uint8_t		remove;						/* Device is marked for removal from the data core. */
+} __rte_cache_aligned;
+
+/*
+ * Device linked list structure for configuration.
+ */
+struct virtio_net_config_ll
+{
+	struct virtio_net		dev;	/* Virtio device. */
+	struct virtio_net_config_ll	*next; /* Next entry on linked list. */
+};
+
+/*
+ * Information relating to memory regions including offsets to addresses in QEMUs memory file.
+ */
+struct virtio_memory_regions {
+	uint64_t	guest_phys_address;		/* Base guest physical address of region. */
+	uint64_t	guest_phys_address_end;	/* End guest physical address of region. */
+	uint64_t	memory_size;			/* Size of region. */
+	uint64_t	userspace_address;		/* Base userspace address of region. */
+	uint64_t	address_offset;			/* Offset of region for address translation. */
+};
+
+/*
+ * Information relating to memory regions including offsets to
+ * addresses in host physical space.
+ */
+struct virtio_memory_regions_hpa {
+	/* Base guest physical address of region. */
+	uint64_t	guest_phys_address;
+	/* End guest physical address of region. */
+	uint64_t	guest_phys_address_end;
+	/* Size of region. */
+	uint64_t	memory_size;
+	/* Offset of region for gpa to hpa translation. */
+	uint64_t	host_phys_addr_offset;
+};
+
+/*
+ * Memory structure includes region and mapping information.
+ */
+struct virtio_memory {
+	uint64_t			base_address;			/* Base QEMU userspace address of the memory file. */
+	uint64_t			mapped_address;			/* Mapped address of memory file base in our applications memory space. */
+	uint64_t			mapped_size;			/* Total size of memory file. */
+	uint32_t			nregions;				/* Number of memory regions. */
+	 /* Number of memory regions for gpa to hpa translation. */
+	uint32_t			nregions_hpa;
+	/* Memory region information for gpa to hpa translation. */
+	struct virtio_memory_regions_hpa  *regions_hpa;
+	/* Memory region information. */
+	struct virtio_memory_regions      regions[0];
+};
+
+/*
+ * Device operations to add/remove device.
+ */
+struct virtio_net_device_ops {
+	int (* new_device) 		(struct virtio_net *);	/* Add device. */
+	void (* destroy_device)	(volatile struct virtio_net *);	/* Remove device. */
+};
+
+int init_virtio_net(struct virtio_net_device_ops const * const);
+int deinit_virtio_net(void);
+
+struct vhost_net_device_ops const * get_virtio_net_callbacks(void);
+
+#endif /* _VIRTIO_NET_H_ */
-- 
1.8.1.4



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