apps: use helper to create mbuf pools
[dpdk.git] / examples / vhost / main.c
index 816a71a..22d6a4b 100644 (file)
@@ -1,13 +1,13 @@
 /*-
  *   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
@@ -17,7 +17,7 @@
  *     * 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
 #include <rte_ethdev.h>
 #include <rte_log.h>
 #include <rte_string_fns.h>
+#include <rte_malloc.h>
+#include <rte_virtio_net.h>
 
 #include "main.h"
-#include "virtio-net.h"
-#include "vhost-net-cdev.h"
 
-#define MAX_QUEUES 128
+#define MAX_QUEUES 512
 
 /* the maximum number of external ports supported */
 #define MAX_SUP_PORTS 1
                                                        (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)
+#define MBUF_CACHE_SIZE 128
+#define MBUF_DATA_SIZE (2048 + RTE_PKTMBUF_HEADROOM)
 
 /*
- * 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.
+ * 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 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 VIRTIO_DESCRIPTOR_LEN_ZCP 1518
+#define MBUF_DATA_SIZE_ZCP (VIRTIO_DESCRIPTOR_LEN_ZCP + RTE_PKTMBUF_HEADROOM)
+#define MBUF_CACHE_SIZE_ZCP 0
 
 #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 ACK_DEV_REMOVAL 0
 
 /* Configurable number of RX/TX ring descriptors */
-#define RTE_TEST_RX_DESC_DEFAULT 1024 
+#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 rte_snprintfs. */
+/* Size of buffers used for snprintfs. */
 #define MAX_PRINT_BUFF 6072
 
 /* Maximum character device basename size. */
 #define MAC_ADDR_CMP 0xFFFFFFFFFFFFULL
 
 /* Number of descriptors per cacheline. */
-#define DESC_PER_CACHELINE (CACHE_LINE_SIZE / sizeof(struct vring_desc))
+#define DESC_PER_CACHELINE (RTE_CACHE_LINE_SIZE / sizeof(struct vring_desc))
+
+#define MBUF_EXT_MEM(mb)   (RTE_MBUF_FROM_BADDR((mb)->buf_addr) != (mb))
 
 /* mask of enabled ports */
 static uint32_t enabled_port_mask = 0;
 
+/* Promiscuous mode */
+static uint32_t promiscuous;
+
 /*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;
+static uint32_t num_devices;
+
+/*
+ * Enable zero copy, pkts buffer will directly dma to hw descriptor,
+ * disabled on default.
+ */
+static uint32_t zero_copy;
+static int mergeable;
+
+/* Do vlan strip on host, enabled on default */
+static uint32_t vlan_strip = 1;
+
+/* 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. */
-static uint32_t enable_vm2vm = 1;
+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. */
@@ -152,39 +205,8 @@ 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 const 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 const 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 const struct rte_eth_conf vmdq_conf_default = {
+static struct rte_eth_conf vmdq_conf_default = {
        .rxmode = {
                .mq_mode        = ETH_MQ_RX_VMDQ_ONLY,
                .split_hdr_size = 0,
@@ -222,7 +244,11 @@ static const struct rte_eth_conf vmdq_conf_default = {
 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 uint16_t num_pf_queues, num_vmdq_queues;
+static uint16_t vmdq_pool_base, vmdq_queue_base;
+static uint16_t queues_per_pool;
 
+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,
@@ -254,6 +280,9 @@ struct mbuf_table {
 /* 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];
@@ -263,6 +292,20 @@ struct vlan_ethhdr {
        __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
@@ -270,9 +313,11 @@ struct vlan_ethhdr {
 /* Per-device statistics struct */
 struct device_statistics {
        uint64_t tx_total;
-       rte_atomic64_t rx_total;
+       rte_atomic64_t rx_total_atomic;
+       uint64_t rx_total;
        uint64_t tx;
-       rte_atomic64_t rx;
+       rte_atomic64_t rx_atomic;
+       uint64_t rx;
 } __rte_cache_aligned;
 struct device_statistics dev_statistics[MAX_DEVICES];
 
@@ -284,11 +329,15 @@ static inline int
 get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_devices)
 {
        struct rte_eth_vmdq_rx_conf conf;
+       struct rte_eth_vmdq_rx_conf *def_conf =
+               &vmdq_conf_default.rx_adv_conf.vmdq_rx_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 = def_conf->enable_loop_back;
+       conf.rx_mode = def_conf->rx_mode;
 
        for (i = 0; i < conf.nb_pool_maps; i++) {
                conf.pool_map[i].vlan_id = vlan_tags[ i ];
@@ -302,15 +351,15 @@ get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_devices)
 }
 
 /*
- * 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.
+ * 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, PORT, "invalid number of devices\n");
+               RTE_LOG(ERR, VHOST_PORT, "invalid number of devices\n");
                return -1;
        }
        return 0;
@@ -321,21 +370,56 @@ validate_num_devices(uint32_t max_nb_devices)
  * coming from the mbuf_pool passed as parameter
  */
 static inline int
-port_init(uint8_t port, struct rte_mempool *mbuf_pool)
+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)rte_lcore_count();
-       const uint16_t rx_ring_size = RTE_TEST_RX_DESC_DEFAULT, tx_ring_size = RTE_TEST_TX_DESC_DEFAULT;
+       struct rte_eth_rxconf *rxconf;
+       struct rte_eth_txconf *txconf;
+       int16_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);
 
+       if (dev_info.max_rx_queues > MAX_QUEUES) {
+               rte_exit(EXIT_FAILURE,
+                       "please define MAX_QUEUES no less than %u in %s\n",
+                       dev_info.max_rx_queues, __FILE__);
+       }
+
+       rxconf = &dev_info.default_rxconf;
+       txconf = &dev_info.default_txconf;
+       rxconf->rx_drop_en = 1;
+
+       /* Enable vlan offload */
+       txconf->txq_flags &= ~ETH_TXQ_FLAGS_NOVLANOFFL;
+
+       /*
+        * Zero copy defers queue RX/TX start to the time when guest
+        * finishes its startup and packet buffers from that guest are
+        * available.
+        */
+       if (zero_copy) {
+               rxconf->rx_deferred_start = 1;
+               rxconf->rx_drop_en = 0;
+               txconf->tx_deferred_start = 1;
+       }
+
        /*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)
@@ -345,10 +429,19 @@ port_init(uint8_t port, struct rte_mempool *mbuf_pool)
        retval = get_eth_conf(&port_conf, num_devices);
        if (retval < 0)
                return retval;
+       /* NIC queues are divided into pf queues and vmdq queues.  */
+       num_pf_queues = dev_info.max_rx_queues - dev_info.vmdq_queue_num;
+       queues_per_pool = dev_info.vmdq_queue_num / dev_info.max_vmdq_pools;
+       num_vmdq_queues = num_devices * queues_per_pool;
+       num_queues = num_pf_queues + num_vmdq_queues;
+       vmdq_queue_base = dev_info.vmdq_queue_base;
+       vmdq_pool_base  = dev_info.vmdq_pool_base;
+       printf("pf queue num: %u, configured vmdq pool num: %u, each vmdq pool has %u queues\n",
+               num_pf_queues, num_devices, queues_per_pool);
 
        if (port >= rte_eth_dev_count()) return -1;
 
-       rx_rings = (uint16_t)num_queues,
+       rx_rings = (uint16_t)dev_info.max_rx_queues;
        /* Configure ethernet device. */
        retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
        if (retval != 0)
@@ -357,26 +450,33 @@ port_init(uint8_t port, struct rte_mempool *mbuf_pool)
        /* 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,
-                                               mbuf_pool);
+                                               rte_eth_dev_socket_id(port),
+                                               rxconf,
+                                               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);
+                                               rte_eth_dev_socket_id(port),
+                                               txconf);
                if (retval < 0)
                        return retval;
        }
 
        /* Start the device. */
        retval  = rte_eth_dev_start(port);
-       if (retval < 0)
+       if (retval < 0) {
+               RTE_LOG(ERR, VHOST_DATA, "Failed to start the device.\n");
                return retval;
+       }
+
+       if (promiscuous)
+               rte_eth_promiscuous_enable(port);
 
        rte_eth_macaddr_get(port, &vmdq_ports_eth_addr[port]);
-       RTE_LOG(INFO, PORT, "Max virtio devices supported: %u\n", num_devices);
-       RTE_LOG(INFO, PORT, "Port %u MAC: %02"PRIx8" %02"PRIx8" %02"PRIx8
+       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],
@@ -400,7 +500,7 @@ us_vhost_parse_basename(const char *q_arg)
        if (strnlen(q_arg, MAX_BASENAME_SZ) > MAX_BASENAME_SZ)
                return -1;
        else
-               rte_snprintf((char*)&dev_basename, MAX_BASENAME_SZ, "%s", q_arg);
+               snprintf((char*)&dev_basename, MAX_BASENAME_SZ, "%s", q_arg);
 
        return 0;
 }
@@ -457,16 +557,26 @@ parse_num_opt(const char *q_arg, uint32_t max_valid_value)
 static void
 us_vhost_usage(const char *prgname)
 {
-       RTE_LOG(INFO, CONFIG, "%s [EAL options] -- -p PORTMASK --vm2vm [0|1] --rx_retry [0|1] --mergeable [0|1] --stats [0-N] --dev-basename <name> --dev-index [0-N] --nb-devices ND\n"
+       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>\n"
+       "               --nb-devices ND\n"
        "               -p PORTMASK: Set mask for ports to be used by application\n"
-       "               --vm2vm [0|1]: disable/enable(default) vm2vm comms\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"
+       "               --vlan-strip [0|1]: disable/enable(default) RX VLAN strip on host\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);
 }
 
@@ -486,35 +596,51 @@ us_vhost_parse_args(int argc, char **argv)
                {"rx-retry-delay", required_argument, NULL, 0},
                {"rx-retry-num", required_argument, NULL, 0},
                {"mergeable", required_argument, NULL, 0},
+               {"vlan-strip", required_argument, NULL, 0},
                {"stats", required_argument, NULL, 0},
                {"dev-basename", required_argument, NULL, 0},
-               {"dev-index", required_argument, NULL, 0},
-               {NULL, 0, 0, 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) {
+       while ((opt = getopt_long(argc, argv, "p: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, CONFIG, "Invalid portmask\n");
+                               RTE_LOG(INFO, VHOST_CONFIG, "Invalid portmask\n");
                                us_vhost_usage(prgname);
                                return -1;
                        }
                        break;
 
+               case 'P':
+                       promiscuous = 1;
+                       vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.rx_mode =
+                               ETH_VMDQ_ACCEPT_BROADCAST |
+                               ETH_VMDQ_ACCEPT_MULTICAST;
+                       rte_vhost_feature_enable(1ULL << VIRTIO_NET_F_CTRL_RX);
+
+                       break;
+
                case 0:
                        /* Enable/disable vm2vm comms. */
-                       if (!strncmp(long_option[option_index].name, "vm2vm", MAX_LONG_OPT_SZ)) {
-                               ret = parse_num_opt(optarg, 1);
+                       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, CONFIG, "Invalid argument for vm2vm [0|1]\n");
+                                       RTE_LOG(INFO, VHOST_CONFIG,
+                                               "Invalid argument for "
+                                               "vm2vm [0|1|2]\n");
                                        us_vhost_usage(prgname);
                                        return -1;
                                } else {
-                                       enable_vm2vm = ret;
+                                       vm2vm_mode = (vm2vm_type)ret;
                                }
                        }
 
@@ -522,7 +648,7 @@ us_vhost_parse_args(int argc, char **argv)
                        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, CONFIG, "Invalid argument for rx-retry [0|1]\n");
+                                       RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry [0|1]\n");
                                        us_vhost_usage(prgname);
                                        return -1;
                                } else {
@@ -534,7 +660,7 @@ us_vhost_parse_args(int argc, char **argv)
                        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, CONFIG, "Invalid argument for rx-retry-delay [0-N]\n");
+                                       RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-delay [0-N]\n");
                                        us_vhost_usage(prgname);
                                        return -1;
                                } else {
@@ -546,7 +672,7 @@ us_vhost_parse_args(int argc, char **argv)
                        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, CONFIG, "Invalid argument for rx-retry-num [0-N]\n");
+                                       RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-num [0-N]\n");
                                        us_vhost_usage(prgname);
                                        return -1;
                                } else {
@@ -558,12 +684,32 @@ us_vhost_parse_args(int argc, char **argv)
                        if (!strncmp(long_option[option_index].name, "mergeable", MAX_LONG_OPT_SZ)) {
                                ret = parse_num_opt(optarg, 1);
                                if (ret == -1) {
-                                       RTE_LOG(INFO, CONFIG, "Invalid argument for mergeable [0|1]\n");
+                                       RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for mergeable [0|1]\n");
+                                       us_vhost_usage(prgname);
+                                       return -1;
+                               } else {
+                                       mergeable = !!ret;
+                                       if (ret) {
+                                               vmdq_conf_default.rxmode.jumbo_frame = 1;
+                                               vmdq_conf_default.rxmode.max_rx_pkt_len
+                                                       = JUMBO_FRAME_MAX_SIZE;
+                                       }
+                               }
+                       }
+
+                       /* Enable/disable RX VLAN strip on host. */
+                       if (!strncmp(long_option[option_index].name,
+                               "vlan-strip", MAX_LONG_OPT_SZ)) {
+                               ret = parse_num_opt(optarg, 1);
+                               if (ret == -1) {
+                                       RTE_LOG(INFO, VHOST_CONFIG,
+                                               "Invalid argument for VLAN strip [0|1]\n");
                                        us_vhost_usage(prgname);
                                        return -1;
                                } else {
-                                       if (ret)
-                                               VHOST_FEATURES = (1ULL << VIRTIO_NET_F_MRG_RXBUF);
+                                       vlan_strip = !!ret;
+                                       vmdq_conf_default.rxmode.hw_vlan_strip =
+                                               vlan_strip;
                                }
                        }
 
@@ -571,7 +717,7 @@ us_vhost_parse_args(int argc, char **argv)
                        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, CONFIG, "Invalid argument for stats [0..N]\n");
+                                       RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for stats [0..N]\n");
                                        us_vhost_usage(prgname);
                                        return -1;
                                } else {
@@ -582,21 +728,53 @@ us_vhost_parse_args(int argc, char **argv)
                        /* 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, CONFIG, "Invalid argument for character device basename (Max %d characters)\n", MAX_BASENAME_SZ);
+                                       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);
+                       /* 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, CONFIG, "Invalid argument for character device index [0..N]\n");
+                                       RTE_LOG(INFO, VHOST_CONFIG,
+                                               "Invalid argument"
+                                               " for zero-copy [0|1]\n");
+                                       us_vhost_usage(prgname);
+                                       return -1;
+                               } else
+                                       zero_copy = ret;
+                       }
+
+                       /* 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 {
-                                       dev_index = ret;
+                                       num_tx_descriptor = ret;
                                }
                        }
 
@@ -615,11 +793,26 @@ us_vhost_parse_args(int argc, char **argv)
        }
 
        if ((num_ports ==  0) || (num_ports > MAX_SUP_PORTS)) {
-               RTE_LOG(INFO, PORT, "Current enabled port number is %u,"
+               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;
 }
 
@@ -633,14 +826,14 @@ static unsigned check_ports_num(unsigned nb_ports)
        unsigned portid;
 
        if (num_ports > nb_ports) {
-               RTE_LOG(INFO, PORT, "\nSpecified port number(%u) exceeds total system port number(%u)\n",
+               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, PORT, "\nSpecified port ID(%u) exceeds max system port ID(%u)\n",
+                       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--;
@@ -660,200 +853,54 @@ static unsigned check_ports_num(unsigned nb_ports)
        char packet[MAX_PRINT_BUFF];                                                                                                                                                                    \
                                                                                                                                                                                                                                        \
        if ((header))                                                                                                                                                                                                   \
-               rte_snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size));                              \
+               snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size));                          \
        else                                                                                                                                                                                                                    \
-               rte_snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size));                              \
+               snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size));                          \
        for (index = 0; index < (size); index++) {                                                                                                                                              \
-               rte_snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF),        \
+               snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF),    \
                        "%02hhx ", pkt_addr[index]);                                                                                                                                                    \
        }                                                                                                                                                                                                                               \
-       rte_snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF), "\n"); \
+       snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF), "\n");     \
                                                                                                                                                                                                                                        \
-       LOG_DEBUG(DATA, "%s", packet);                                                                                                                                                                  \
+       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.
+ * 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_vva(struct virtio_net *dev, uint64_t guest_pa)
+gpa_to_hpa(struct vhost_dev  *vdev, uint64_t guest_pa,
+       uint32_t buf_len, hpa_type *addr_type)
 {
-       struct virtio_memory_regions *region;
+       struct virtio_memory_regions_hpa *region;
        uint32_t regionidx;
-       uint64_t vhost_va = 0;
+       uint64_t vhost_pa = 0;
 
-       for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-               region = &dev->mem->regions[regionidx];
+       *addr_type = PHYS_ADDR_INVALID;
+
+       for (regionidx = 0; regionidx < vdev->nregions_hpa; regionidx++) {
+               region = &vdev->regions_hpa[regionidx];
                if ((guest_pa >= region->guest_phys_address) &&
                        (guest_pa <= region->guest_phys_address_end)) {
-                       vhost_va = region->address_offset + guest_pa;
+                       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(DATA, "(%"PRIu64") GPA %p| VVA %p\n",
-               dev->device_fh, (void*)(uintptr_t)guest_pa, (void*)(uintptr_t)vhost_va);
-
-       return vhost_va;
-}
-
-/*
- * 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.
- */
-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 mergeable, mrg_count = 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(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(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)]);
-
-       /* Check if the VIRTIO_NET_F_MRG_RXBUF feature is enabled. */
-       mergeable = dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
-
-       /* 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);
-
-               if (mergeable && (mrg_count != 0)) {
-                       desc->len = packet_len = rte_pktmbuf_data_len(buff);
-               } else {
-                       /* 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;
-                       }
-               }
-
-               PRINT_PACKET(dev, (uintptr_t)buff_addr, rte_pktmbuf_data_len(buff), 0);
-
-               /* 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));
-
-               res_cur_idx++;
-               packet_success++;
-
-               /* If mergeable is disabled then a header is required per buffer. */
-               if (!mergeable) {
-                       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);
-               } else {
-                       mrg_count++;
-                       /* Merge buffer can only handle so many buffers at a time. Tell the guest if this limit is reached. */
-                       if ((mrg_count == MAX_MRG_PKT_BURST) || (res_cur_idx == res_end_idx)) {
-                               virtio_hdr.num_buffers = mrg_count;
-                               LOG_DEBUG(DATA, "(%"PRIu64") RX: Num merge buffers %d\n", dev->device_fh, virtio_hdr.num_buffers);
-                               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);
-                               mrg_count = 0;
-                       }
-               }
-               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;
+       LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| HPA %p\n",
+               vdev->dev->device_fh, (void *)(uintptr_t)guest_pa,
+               (void *)(uintptr_t)vhost_pa);
 
-       /* Kick the guest if necessary. */
-       if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-               eventfd_write((int)vq->kickfd, 1);
-       return count;
+       return vhost_pa;
 }
 
 /*
@@ -870,51 +917,54 @@ ether_addr_cmp(struct ether_addr *ea, struct ether_addr *eb)
  * vlan tag to a VMDQ.
  */
 static int
-link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
+link_vmdq(struct vhost_dev *vdev, struct rte_mbuf *m)
 {
        struct ether_hdr *pkt_hdr;
        struct virtio_net_data_ll *dev_ll;
+       struct virtio_net *dev = vdev->dev;
        int i, ret;
 
        /* Learn MAC address of guest device from packet */
-       pkt_hdr = (struct ether_hdr *)m->pkt.data;
+       pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
 
        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, DATA, "(%"PRIu64") WARNING: This device is using an existing MAC address and has not been registered.\n", dev->device_fh);
+               if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->vdev->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];
+               vdev->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];
-       dev->vmdq_rx_q = dev->device_fh * (num_queues/num_devices);
+       vdev->vlan_tag = vlan_tags[dev->device_fh];
 
        /* Print out VMDQ registration info. */
-       RTE_LOG(INFO, DATA, "(%"PRIu64") MAC_ADDRESS %02x:%02x:%02x:%02x:%02x:%02x and VLAN_TAG %d registered\n",
+       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);
+               vdev->mac_address.addr_bytes[0], vdev->mac_address.addr_bytes[1],
+               vdev->mac_address.addr_bytes[2], vdev->mac_address.addr_bytes[3],
+               vdev->mac_address.addr_bytes[4], vdev->mac_address.addr_bytes[5],
+               vdev->vlan_tag);
 
        /* Register the MAC address. */
-       ret = rte_eth_dev_mac_addr_add(ports[0], &dev->mac_address, (uint32_t)dev->device_fh);
+       ret = rte_eth_dev_mac_addr_add(ports[0], &vdev->mac_address,
+                               (uint32_t)dev->device_fh + vmdq_pool_base);
        if (ret)
-               RTE_LOG(ERR, DATA, "(%"PRIu64") Failed to add device MAC address to VMDQ\n",
+               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);
+       if (vlan_strip)
+               rte_eth_dev_set_vlan_strip_on_queue(ports[0],
+                       (uint16_t)vdev->vmdq_rx_q, 1);
 
        /* Set device as ready for RX. */
-       dev->ready = DEVICE_RX;
+       vdev->ready = DEVICE_RX;
 
        return 0;
 }
@@ -924,33 +974,33 @@ link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
  * queue before disabling RX on the device.
  */
 static inline void
-unlink_vmdq(struct virtio_net *dev)
+unlink_vmdq(struct vhost_dev *vdev)
 {
        unsigned i = 0;
        unsigned rx_count;
        struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
 
-       if (dev->ready == DEVICE_RX) {
+       if (vdev->ready == DEVICE_RX) {
                /*clear MAC and VLAN settings*/
-               rte_eth_dev_mac_addr_remove(ports[0], &dev->mac_address);
+               rte_eth_dev_mac_addr_remove(ports[0], &vdev->mac_address);
                for (i = 0; i < 6; i++)
-                       dev->mac_address.addr_bytes[i] = 0;
+                       vdev->mac_address.addr_bytes[i] = 0;
 
-               dev->vlan_tag = 0;
+               vdev->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);
+                                       (uint16_t)vdev->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);
+                                       (uint16_t)vdev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
                }
 
-               dev->ready = DEVICE_MAC_LEARNING;
+               vdev->ready = DEVICE_MAC_LEARNING;
        }
 }
 
@@ -958,43 +1008,50 @@ unlink_vmdq(struct virtio_net *dev)
  * 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)
+static inline int __attribute__((always_inline))
+virtio_tx_local(struct vhost_dev *vdev, struct rte_mbuf *m)
 {
        struct virtio_net_data_ll *dev_ll;
        struct ether_hdr *pkt_hdr;
        uint64_t ret = 0;
+       struct virtio_net *dev = vdev->dev;
+       struct virtio_net *tdev; /* destination virito device */
 
-       pkt_hdr = (struct ether_hdr *)m->pkt.data;
+       pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
 
        /*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)) {
+               if ((dev_ll->vdev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
+                                         &dev_ll->vdev->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(DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
-                                                       dev_ll->dev->device_fh);
+                       if (dev_ll->vdev->dev->device_fh == dev->device_fh) {
+                               LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
+                                                       dev->device_fh);
                                return 0;
                        }
+                       tdev = dev_ll->vdev->dev;
 
 
-                       LOG_DEBUG(DATA, "(%"PRIu64") TX: MAC address is local\n", dev_ll->dev->device_fh);
+                       LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", tdev->device_fh);
 
-                       if (dev_ll->dev->remove) {
+                       if (unlikely(dev_ll->vdev->remove)) {
                                /*drop the packet if the device is marked for removal*/
-                               LOG_DEBUG(DATA, "(%"PRIu64") Device is marked for removal\n", dev_ll->dev->device_fh);
+                               LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", tdev->device_fh);
                        } else {
                                /*send the packet to the local virtio device*/
-                               ret = virtio_dev_rx(dev_ll->dev, &m, 1);
+                               ret = rte_vhost_enqueue_burst(tdev, VIRTIO_RXQ, &m, 1);
                                if (enable_stats) {
-                                       rte_atomic64_add(&dev_statistics[dev_ll->dev->device_fh].rx_total, 1);
-                                       rte_atomic64_add(&dev_statistics[dev_ll->dev->device_fh].rx, ret);
-                                       dev_statistics[dev->device_fh].tx_total++;
-                                       dev_statistics[dev->device_fh].tx += ret;
+                                       rte_atomic64_add(
+                                       &dev_statistics[tdev->device_fh].rx_total_atomic,
+                                       1);
+                                       rte_atomic64_add(
+                                       &dev_statistics[tdev->device_fh].rx_atomic,
+                                       ret);
+                                       dev_statistics[tdev->device_fh].tx_total++;
+                                       dev_statistics[tdev->device_fh].tx += ret;
                                }
                        }
 
@@ -1006,55 +1063,124 @@ virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
        return -1;
 }
 
+/*
+ * Check if the destination MAC of a packet is one local VM,
+ * and get its vlan tag, and offset if it is.
+ */
+static inline int __attribute__((always_inline))
+find_local_dest(struct virtio_net *dev, struct rte_mbuf *m,
+       uint32_t *offset, uint16_t *vlan_tag)
+{
+       struct virtio_net_data_ll *dev_ll = ll_root_used;
+       struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
+
+       while (dev_ll != NULL) {
+               if ((dev_ll->vdev->ready == DEVICE_RX)
+                       && ether_addr_cmp(&(pkt_hdr->d_addr),
+               &dev_ll->vdev->mac_address)) {
+                       /*
+                        * Drop the packet if the TX packet is
+                        * destined for the TX device.
+                        */
+                       if (dev_ll->vdev->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->vdev->dev->device_fh);
+                               return -1;
+                       }
+
+                       /*
+                        * HW vlan strip will reduce the packet length
+                        * by minus length of vlan tag, so need restore
+                        * the packet length by plus it.
+                        */
+                       *offset = VLAN_HLEN;
+                       *vlan_tag =
+                       (uint16_t)
+                       vlan_tags[(uint16_t)dev_ll->vdev->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->vdev->dev->device_fh,
+                       vlan_tag);
+
+                       break;
+               }
+               dev_ll = dev_ll->next;
+       }
+       return 0;
+}
+
 /*
  * 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)
+virtio_tx_route(struct vhost_dev *vdev, struct rte_mbuf *m, uint16_t vlan_tag)
 {
        struct mbuf_table *tx_q;
-       struct vlan_ethhdr *vlan_hdr;
        struct rte_mbuf **m_table;
-       struct rte_mbuf *mbuf;
-       unsigned len, ret;
+       unsigned len, ret, offset = 0;
        const uint16_t lcore_id = rte_lcore_id();
+       struct virtio_net *dev = vdev->dev;
+       struct ether_hdr *nh;
 
        /*check if destination is local VM*/
-       if (enable_vm2vm && (virtio_tx_local(dev, m) == 0)) {
+       if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(vdev, m) == 0)) {
+               rte_pktmbuf_free(m);
                return;
        }
 
-       LOG_DEBUG(DATA, "(%"PRIu64") TX: MAC address is external\n", dev->device_fh);
+       if (unlikely(vm2vm_mode == VM2VM_HARDWARE)) {
+               if (unlikely(find_local_dest(dev, m, &offset, &vlan_tag) != 0)) {
+                       rte_pktmbuf_free(m);
+                       return;
+               }
+       }
+
+       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, DATA, "Failed to allocate memory for mbuf.\n");
-               return;
-       }
+       nh = rte_pktmbuf_mtod(m, struct ether_hdr *);
+       if (unlikely(nh->ether_type == rte_cpu_to_be_16(ETHER_TYPE_VLAN))) {
+               /* Guest has inserted the vlan tag. */
+               struct vlan_hdr *vh = (struct vlan_hdr *) (nh + 1);
+               uint16_t vlan_tag_be = rte_cpu_to_be_16(vlan_tag);
+               if ((vm2vm_mode == VM2VM_HARDWARE) &&
+                       (vh->vlan_tci != vlan_tag_be))
+                       vh->vlan_tci = vlan_tag_be;
+       } else {
+               m->ol_flags = PKT_TX_VLAN_PKT;
 
-       mbuf->pkt.data_len = m->pkt.data_len + VLAN_HLEN;
-       mbuf->pkt.pkt_len = mbuf->pkt.data_len;
+               /*
+                * Find the right seg to adjust the data len when offset is
+                * bigger than tail room size.
+                */
+               if (unlikely(vm2vm_mode == VM2VM_HARDWARE)) {
+                       if (likely(offset <= rte_pktmbuf_tailroom(m)))
+                               m->data_len += offset;
+                       else {
+                               struct rte_mbuf *seg = m;
 
-       /* Copy ethernet header to mbuf. */
-       rte_memcpy((void*)mbuf->pkt.data, (const void*)m->pkt.data, ETH_HLEN);
+                               while ((seg->next != NULL) &&
+                                       (offset > rte_pktmbuf_tailroom(seg)))
+                                       seg = seg->next;
 
+                               seg->data_len += offset;
+                       }
+                       m->pkt_len += offset;
+               }
 
-       /* 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);
+               m->vlan_tci = 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));
-       tx_q->m_table[len] = mbuf;
+       tx_q->m_table[len] = m;
        len++;
        if (enable_stats) {
                dev_statistics[dev->device_fh].tx_total++;
@@ -1077,99 +1203,6 @@ virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *
        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(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(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.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 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
@@ -1180,6 +1213,7 @@ switch_worker(__attribute__((unused)) void *arg)
 {
        struct rte_mempool *mbuf_pool = arg;
        struct virtio_net *dev = NULL;
+       struct vhost_dev *vdev = NULL;
        struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
        struct virtio_net_data_ll *dev_ll;
        struct mbuf_table *tx_q;
@@ -1190,8 +1224,10 @@ switch_worker(__attribute__((unused)) void *arg)
        const uint16_t lcore_id = rte_lcore_id();
        const uint16_t num_cores = (uint16_t)rte_lcore_count();
        uint16_t rx_count = 0;
+       uint16_t tx_count;
+       uint32_t retry = 0;
 
-       RTE_LOG(INFO, DATA, "Procesing on Core %u started \n", lcore_id);
+       RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
        lcore_ll = lcore_info[lcore_id].lcore_ll;
        prev_tsc = 0;
 
@@ -1212,7 +1248,7 @@ switch_worker(__attribute__((unused)) void *arg)
                if (unlikely(diff_tsc > drain_tsc)) {
 
                        if (tx_q->len) {
-                               LOG_DEBUG(DATA, "TX queue drained after timeout with burst size %u \n", 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,
@@ -1232,11 +1268,11 @@ switch_worker(__attribute__((unused)) void *arg)
                }
 
                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) 
+               if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
                        lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
 
                /*
@@ -1246,38 +1282,63 @@ switch_worker(__attribute__((unused)) void *arg)
 
                while (dev_ll != NULL) {
                        /*get virtio device ID*/
-                       dev = dev_ll->dev;
+                       vdev = dev_ll->vdev;
+                       dev = vdev->dev;
 
-                       if (dev->remove) {
+                       if (unlikely(vdev->remove)) {
                                dev_ll = dev_ll->next;
-                               unlink_vmdq(dev);
-                               dev->ready = DEVICE_SAFE_REMOVE;
+                               unlink_vmdq(vdev);
+                               vdev->ready = DEVICE_SAFE_REMOVE;
                                continue;
                        }
-                       if (likely(dev->ready == DEVICE_RX)) {
+                       if (likely(vdev->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);
+                                       vdev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
 
                                if (rx_count) {
-                                       ret_count = virtio_dev_rx(dev, pkts_burst, rx_count);
+                                       /*
+                                       * Retry is enabled and the queue is full then we wait and retry to avoid packet loss
+                                       * Here MAX_PKT_BURST must be less than virtio queue size
+                                       */
+                                       if (enable_retry && unlikely(rx_count > rte_vring_available_entries(dev, VIRTIO_RXQ))) {
+                                               for (retry = 0; retry < burst_rx_retry_num; retry++) {
+                                                       rte_delay_us(burst_rx_delay_time);
+                                                       if (rx_count <= rte_vring_available_entries(dev, VIRTIO_RXQ))
+                                                               break;
+                                               }
+                                       }
+                                       ret_count = rte_vhost_enqueue_burst(dev, VIRTIO_RXQ, pkts_burst, rx_count);
                                        if (enable_stats) {
-                                               rte_atomic64_add(&dev_statistics[dev_ll->dev->device_fh].rx_total, rx_count);
-                                               rte_atomic64_add(&dev_statistics[dev_ll->dev->device_fh].rx, ret_count);
+                                               rte_atomic64_add(
+                                               &dev_statistics[dev_ll->vdev->dev->device_fh].rx_total_atomic,
+                                               rx_count);
+                                               rte_atomic64_add(
+                                               &dev_statistics[dev_ll->vdev->dev->device_fh].rx_atomic, ret_count);
                                        }
                                        while (likely(rx_count)) {
                                                rx_count--;
-                                               rte_pktmbuf_free_seg(pkts_burst[rx_count]);
+                                               rte_pktmbuf_free(pkts_burst[rx_count]);
                                        }
 
                                }
                        }
 
-                       if (!dev->remove)
-                               /*Handle guest TX*/
-                               virtio_dev_tx(dev, mbuf_pool);
-
-                       /*move to the next device in the list*/
+                       if (likely(!vdev->remove)) {
+                               /* Handle guest TX*/
+                               tx_count = rte_vhost_dequeue_burst(dev, VIRTIO_TXQ, mbuf_pool, pkts_burst, MAX_PKT_BURST);
+                               /* If this is the first received packet we need to learn the MAC and setup VMDQ */
+                               if (unlikely(vdev->ready == DEVICE_MAC_LEARNING) && tx_count) {
+                                       if (vdev->remove || (link_vmdq(vdev, pkts_burst[0]) == -1)) {
+                                               while (tx_count)
+                                                       rte_pktmbuf_free(pkts_burst[--tx_count]);
+                                       }
+                               }
+                               while (tx_count)
+                                       virtio_tx_route(vdev, pkts_burst[--tx_count], (uint16_t)dev->device_fh);
+                       }
+
+                       /*move to the next device in the list*/
                        dev_ll = dev_ll->next;
                }
        }
@@ -1286,11 +1347,836 @@ switch_worker(__attribute__((unused)) void *arg)
 }
 
 /*
- * 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();
+ * 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->callfd, 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;
+       struct vhost_dev *vdev = (struct vhost_dev *)dev->priv;
+
+       vpool = &vpool_array[vdev->vmdq_rx_q];
+       vq = dev->virtqueue[VIRTIO_RXQ];
+
+       do {
+               if (unlikely(get_available_ring_index_zcp(vdev->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(vdev, desc->addr, desc->len,
+                                       &addr_type);
+               } else {
+                       buff_addr = gpa_to_vva(dev,
+                                       desc->addr + vq->vhost_hlen);
+                       phys_addr = gpa_to_hpa(vdev,
+                                       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->data_off = RTE_PKTMBUF_HEADROOM;
+       mbuf->buf_physaddr = phys_addr - RTE_PKTMBUF_HEADROOM;
+       mbuf->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->data_off = buf_ofs;
+
+       m->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(MBUF_EXT_MEM(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->callfd, 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(MBUF_EXT_MEM(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->callfd, 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;
+       uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
+       uint16_t vmdq_rx_q = ((struct vhost_dev *)dev->priv)->vmdq_rx_q;
+
+       /*Add packet to the port tx queue*/
+       tx_q = &tx_queue_zcp[vmdq_rx_q];
+       len = tx_q->len;
+
+       /* Allocate an mbuf and populate the structure. */
+       vpool = &vpool_array[MAX_QUEUES + 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;
+               if (find_local_dest(dev, m, &offset, &vlan_tag) != 0) {
+                       MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
+                       __rte_mbuf_raw_free(mbuf);
+                       return;
+               }
+       }
+
+       mbuf->nb_segs = m->nb_segs;
+       mbuf->next = m->next;
+       mbuf->data_len = m->data_len + offset;
+       mbuf->pkt_len = mbuf->data_len;
+       if (unlikely(need_copy)) {
+               /* Copy the packet contents to the mbuf. */
+               rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
+                       rte_pktmbuf_mtod(m, void *),
+                       m->data_len);
+       } else {
+               mbuf->data_off = m->data_off;
+               mbuf->buf_physaddr = m->buf_physaddr;
+               mbuf->buf_addr = m->buf_addr;
+       }
+       mbuf->ol_flags = PKT_TX_VLAN_PKT;
+       mbuf->vlan_tci = vlan_tag;
+       mbuf->l2_len = sizeof(struct ether_hdr);
+       mbuf->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->nb_segs,
+               (mbuf->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;
+       struct vhost_dev *vdev = (struct vhost_dev *)dev->priv;
+
+       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);
+               /* Need check extra VLAN_HLEN size for inserting VLAN tag */
+               phys_addr = gpa_to_hpa(vdev, desc->addr, desc->len + VLAN_HLEN,
+                       &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.data_len = desc->len;
+               m.nb_segs = 1;
+               m.next = NULL;
+               m.data_off = 0;
+               m.buf_addr = (void *)(uintptr_t)buff_addr;
+               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(vdev->ready == DEVICE_MAC_LEARNING)) {
+                       if (vdev->remove || (link_vmdq(vdev, &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 vhost_dev  *vdev = 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->vdev != NULL)) {
+                               /* Get virtio device ID */
+                               vdev = dev_ll->vdev;
+                               dev = vdev->dev;
+
+                               if (likely(!vdev->remove)) {
+                                       tx_q = &tx_queue_zcp[(uint16_t)vdev->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+vdev->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->vdev != NULL)) {
+                       vdev = dev_ll->vdev;
+                       dev  = vdev->dev;
+                       if (unlikely(vdev->remove)) {
+                               dev_ll = dev_ll->next;
+                               unlink_vmdq(vdev);
+                               vdev->ready = DEVICE_SAFE_REMOVE;
+                               continue;
+                       }
+
+                       if (likely(vdev->ready == DEVICE_RX)) {
+                               uint32_t index = vdev->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],
+                                       vdev->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(!vdev->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)
+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;
 
@@ -1311,14 +2197,16 @@ add_data_ll_entry(struct virtio_net_data_ll **ll_root_addr, struct virtio_net_da
 }
 
 /*
- * 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().
+ * 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)
+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;
 
@@ -1328,7 +2216,7 @@ rm_data_ll_entry(struct virtio_net_data_ll **ll_root_addr, struct virtio_net_dat
                if (likely(ll_dev_last != NULL))
                        ll_dev_last->next = ll_dev->next;
                else
-                       RTE_LOG(ERR, CONFIG, "Remove entry form ll failed.\n");
+                       RTE_LOG(ERR, VHOST_CONFIG, "Remove entry form ll failed.\n");
 }
 
 /*
@@ -1353,7 +2241,8 @@ get_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr)
  * 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)
+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;
 
@@ -1376,12 +2265,12 @@ alloc_data_ll(uint32_t size)
        /* Malloc and then chain the linked list. */
        ll_new = malloc(size * sizeof(struct virtio_net_data_ll));
        if (ll_new == NULL) {
-               RTE_LOG(ERR, CONFIG, "Failed to allocate memory for ll_new.\n");
+               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].vdev = NULL;
                ll_new[i].next = &ll_new[i+1];
        }
        ll_new[i].next = NULL;
@@ -1401,7 +2290,7 @@ init_data_ll (void)
        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, CONFIG, "Failed to allocate memory for lcore_ll.\n");
+                       RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for lcore_ll.\n");
                        return -1;
                }
 
@@ -1421,18 +2310,8 @@ init_data_ll (void)
 }
 
 /*
- * 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 
+ * 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
@@ -1442,21 +2321,22 @@ destroy_device (volatile struct virtio_net *dev)
        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;
+       struct vhost_dev *vdev;
        int lcore;
 
        dev->flags &= ~VIRTIO_DEV_RUNNING;
 
+       vdev = (struct vhost_dev *)dev->priv;
        /*set the remove flag. */
-       dev->remove = 1;
-
-       while(dev->ready != DEVICE_SAFE_REMOVE) {
+       vdev->remove = 1;
+       while(vdev->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;
+       ll_lcore_dev_cur = lcore_info[vdev->coreid].lcore_ll->ll_root_used;
        while (ll_lcore_dev_cur != NULL) {
-               if (ll_lcore_dev_cur->dev == dev) {
+               if (ll_lcore_dev_cur->vdev == vdev) {
                        break;
                } else {
                        ll_lcore_dev_last = ll_lcore_dev_cur;
@@ -1465,7 +2345,9 @@ destroy_device (volatile struct virtio_net *dev)
        }
 
        if (ll_lcore_dev_cur == NULL) {
-               RTE_LOG(ERR, CONFIG, "Failed to find the dev to be destroy.\n");
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "(%"PRIu64") Failed to find the dev to be destroy.\n",
+                       dev->device_fh);
                return;
        }
 
@@ -1473,7 +2355,7 @@ destroy_device (volatile struct virtio_net *dev)
        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) {
+               if (ll_main_dev_cur->vdev == vdev) {
                        break;
                } else {
                        ll_main_dev_last = ll_main_dev_cur;
@@ -1482,15 +2364,15 @@ destroy_device (volatile struct virtio_net *dev)
        }
 
        /* 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(&lcore_info[vdev->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.
@@ -1502,13 +2384,201 @@ destroy_device (volatile struct virtio_net *dev)
        }
 
        /* 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(&lcore_info[vdev->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, DATA, "(%"PRIu64") Device has been removed from data core\n", dev->device_fh);
+       lcore_info[vdev->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[vdev->vmdq_rx_q];
+
+               /* Stop the RX queue. */
+               if (rte_eth_dev_rx_queue_stop(ports[0], vdev->vmdq_rx_q) != 0) {
+                       LOG_DEBUG(VHOST_CONFIG,
+                               "(%"PRIu64") In destroy_device: Failed to stop "
+                               "rx queue:%d\n",
+                               dev->device_fh,
+                               vdev->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, vdev->vmdq_rx_q);
+
+               mbuf_destroy_zcp(vpool);
+
+               /* Stop the TX queue. */
+               if (rte_eth_dev_tx_queue_stop(ports[0], vdev->vmdq_rx_q) != 0) {
+                       LOG_DEBUG(VHOST_CONFIG,
+                               "(%"PRIu64") In destroy_device: Failed to "
+                               "stop tx queue:%d\n",
+                               dev->device_fh, vdev->vmdq_rx_q);
+               }
+
+               vpool = &vpool_array[vdev->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, (vdev->vmdq_rx_q + MAX_QUEUES),
+                       dev->device_fh);
+
+               mbuf_destroy_zcp(vpool);
+               rte_free(vdev->regions_hpa);
+       }
+       rte_free(vdev);
+
+}
+
+/*
+ * 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 = getpagesize();
+       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(struct virtio_memory_regions_hpa *mem_region_hpa, struct virtio_memory *virtio_memory)
+{
+       uint32_t regionidx, regionidx_hpa = 0, i, k, page_size = getpagesize();
+       uint64_t cur_phys_addr = 0, next_phys_addr = 0, vva_start;
+
+       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;
 }
 
 /*
@@ -1521,21 +2591,147 @@ 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;
+       struct vhost_dev *vdev;
+       uint32_t regionidx;
+
+       vdev = rte_zmalloc("vhost device", sizeof(*vdev), RTE_CACHE_LINE_SIZE);
+       if (vdev == NULL) {
+               RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Couldn't allocate memory for vhost dev\n",
+                       dev->device_fh);
+               return -1;
+       }
+       vdev->dev = dev;
+       dev->priv = vdev;
+
+       if (zero_copy) {
+               vdev->nregions_hpa = dev->mem->nregions;
+               for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+                       vdev->nregions_hpa
+                               += check_hpa_regions(
+                                       dev->mem->regions[regionidx].guest_phys_address
+                                       + dev->mem->regions[regionidx].address_offset,
+                                       dev->mem->regions[regionidx].memory_size);
+
+               }
+
+               vdev->regions_hpa = rte_calloc("vhost hpa region",
+                                              vdev->nregions_hpa,
+                                              sizeof(struct virtio_memory_regions_hpa),
+                                              RTE_CACHE_LINE_SIZE);
+               if (vdev->regions_hpa == NULL) {
+                       RTE_LOG(ERR, VHOST_CONFIG, "Cannot allocate memory for hpa region\n");
+                       rte_free(vdev);
+                       return -1;
+               }
+
+
+               if (fill_hpa_memory_regions(
+                       vdev->regions_hpa, dev->mem
+                       ) != vdev->nregions_hpa) {
+
+                       RTE_LOG(ERR, VHOST_CONFIG,
+                               "hpa memory regions number mismatch: "
+                               "[%d]\n", vdev->nregions_hpa);
+                       rte_free(vdev->regions_hpa);
+                       rte_free(vdev);
+                       return -1;
+               }
+       }
+
 
        /* Add device to main ll */
        ll_dev = get_data_ll_free_entry(&ll_root_free);
        if (ll_dev == NULL) {
-               RTE_LOG(INFO, DATA, "(%"PRIu64") No free entry found in linked list. Device limit "
+               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);
+               if (vdev->regions_hpa)
+                       rte_free(vdev->regions_hpa);
+               rte_free(vdev);
                return -1;
        }
-       ll_dev->dev = dev;
+       ll_dev->vdev = vdev;
        add_data_ll_entry(&ll_root_used, ll_dev);
+       vdev->vmdq_rx_q
+               = dev->device_fh * queues_per_pool + vmdq_queue_base;
+
+       if (zero_copy) {
+               uint32_t index = vdev->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)vdev->vmdq_rx_q];
+               tx_q->txq_id = vdev->vmdq_rx_q;
+
+               if (rte_eth_dev_tx_queue_start(ports[0], vdev->vmdq_rx_q) != 0) {
+                       struct vpool *vpool = &vpool_array[vdev->vmdq_rx_q];
+
+                       LOG_DEBUG(VHOST_CONFIG,
+                               "(%"PRIu64") In new_device: Failed to start "
+                               "tx queue:%d\n",
+                               dev->device_fh, vdev->vmdq_rx_q);
+
+                       mbuf_destroy_zcp(vpool);
+                       rte_free(vdev->regions_hpa);
+                       rte_free(vdev);
+                       return -1;
+               }
+
+               if (rte_eth_dev_rx_queue_start(ports[0], vdev->vmdq_rx_q) != 0) {
+                       struct vpool *vpool = &vpool_array[vdev->vmdq_rx_q];
+
+                       LOG_DEBUG(VHOST_CONFIG,
+                               "(%"PRIu64") In new_device: Failed to start "
+                               "rx queue:%d\n",
+                               dev->device_fh, vdev->vmdq_rx_q);
+
+                       /* Stop the TX queue. */
+                       if (rte_eth_dev_tx_queue_stop(ports[0],
+                               vdev->vmdq_rx_q) != 0) {
+                               LOG_DEBUG(VHOST_CONFIG,
+                                       "(%"PRIu64") In new_device: Failed to "
+                                       "stop tx queue:%d\n",
+                                       dev->device_fh, vdev->vmdq_rx_q);
+                       }
+
+                       mbuf_destroy_zcp(vpool);
+                       rte_free(vdev->regions_hpa);
+                       rte_free(vdev);
+                       return -1;
+               }
+
+       }
 
        /*reset ready flag*/
-       dev->ready = DEVICE_MAC_LEARNING;
-       dev->remove = 0;
+       vdev->ready = DEVICE_MAC_LEARNING;
+       vdev->remove = 0;
 
        /* Find a suitable lcore to add the device. */
        RTE_LCORE_FOREACH_SLAVE(lcore) {
@@ -1545,25 +2741,30 @@ new_device (struct virtio_net *dev)
                }
        }
        /* 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);
+       ll_dev = get_data_ll_free_entry(&lcore_info[core_add].lcore_ll->ll_root_free);
        if (ll_dev == NULL) {
-               RTE_LOG(INFO, DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
+               RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
+               vdev->ready = DEVICE_SAFE_REMOVE;
                destroy_device(dev);
+               rte_free(vdev->regions_hpa);
+               rte_free(vdev);
                return -1;
        }
-       ll_dev->dev = dev;
-       add_data_ll_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_used, ll_dev);
+       ll_dev->vdev = vdev;
+       vdev->coreid = core_add;
+
+       add_data_ll_entry(&lcore_info[vdev->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++;
+       rte_vhost_enable_guest_notification(dev, VIRTIO_RXQ, 0);
+       rte_vhost_enable_guest_notification(dev, VIRTIO_TXQ, 0);
+       lcore_info[vdev->coreid].lcore_ll->device_num++;
        dev->flags |= VIRTIO_DEV_RUNNING;
 
-       RTE_LOG(INFO, DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, dev->coreid);
+       RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, vdev->coreid);
 
        return 0;
 }
@@ -1602,12 +2803,19 @@ print_stats(void)
 
                dev_ll = ll_root_used;
                while (dev_ll != NULL) {
-                       device_fh = (uint32_t)dev_ll->dev->device_fh;
+                       device_fh = (uint32_t)dev_ll->vdev->dev->device_fh;
                        tx_total = dev_statistics[device_fh].tx_total;
                        tx = dev_statistics[device_fh].tx;
                        tx_dropped = tx_total - tx;
-                       rx_total = rte_atomic64_read(&dev_statistics[device_fh].rx_total);
-                       rx = rte_atomic64_read(&dev_statistics[device_fh].rx);
+                       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" ------------------------------"
@@ -1631,18 +2839,52 @@ print_stats(void)
        }
 }
 
+static void
+setup_mempool_tbl(int socket, uint32_t index, char *pool_name,
+       char *ring_name, uint32_t nb_mbuf)
+{
+       vpool_array[index].pool = rte_pktmbuf_pool_create(pool_name, nb_mbuf,
+               MBUF_CACHE_SIZE_ZCP, 0, MBUF_DATA_SIZE_ZCP, socket);
+       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 = VIRTIO_DESCRIPTOR_LEN_ZCP;
+       } 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[])
+main(int argc, char *argv[])
 {
-       struct rte_mempool *mbuf_pool;
+       struct rte_mempool *mbuf_pool = NULL;
        unsigned lcore_id, core_id = 0;
        unsigned nb_ports, valid_num_ports;
        int ret;
        uint8_t portid;
+       uint16_t queue_id;
        static pthread_t tid;
 
        /* init EAL */
@@ -1657,9 +2899,6 @@ MAIN(int argc, char *argv[])
        if (ret < 0)
                rte_exit(EXIT_FAILURE, "Invalid argument\n");
 
-       if (rte_pmd_init_all() != 0 || 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;
@@ -1676,27 +2915,73 @@ MAIN(int argc, char *argv[])
                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
-        */
+        * 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, PORT, "Current enabled port number is %u,"
+               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;
        }
 
-       /* 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");
+       if (zero_copy == 0) {
+               /* Create the mbuf pool. */
+               mbuf_pool = rte_pktmbuf_pool_create("MBUF_POOL",
+                       NUM_MBUFS_PER_PORT * valid_num_ports, MBUF_CACHE_SIZE,
+                       0, MBUF_DATA_SIZE, rte_socket_id());
+               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];
+
+               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);
 
@@ -1704,11 +2989,13 @@ MAIN(int argc, char *argv[])
        for (portid = 0; portid < nb_ports; portid++) {
                /* skip ports that are not enabled */
                if ((enabled_port_mask & (1 << portid)) == 0) {
-                       RTE_LOG(INFO, PORT, "Skipping disabled port %d\n", portid);
+                       RTE_LOG(INFO, VHOST_PORT,
+                               "Skipping disabled port %d\n", portid);
                        continue;
                }
-               if (port_init(portid, mbuf_pool) != 0)
-                       rte_exit(EXIT_FAILURE, "Cannot initialize network ports\n");
+               if (port_init(portid) != 0)
+                       rte_exit(EXIT_FAILURE,
+                               "Cannot initialize network ports\n");
        }
 
        /* Initialise all linked lists. */
@@ -1723,19 +3010,56 @@ MAIN(int argc, char *argv[])
                pthread_create(&tid, NULL, (void*)print_stats, NULL );
 
        /* Launch all data cores. */
-       RTE_LCORE_FOREACH_SLAVE(lcore_id) {
-               rte_eal_remote_launch(switch_worker, mbuf_pool, lcore_id);
+       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);
        }
 
+       if (mergeable == 0)
+               rte_vhost_feature_disable(1ULL << VIRTIO_NET_F_MRG_RXBUF);
+
        /* Register CUSE device to handle IOCTLs. */
-       ret = register_cuse_device((char*)&dev_basename, dev_index, get_virtio_net_callbacks());
+       ret = rte_vhost_driver_register((char *)&dev_basename);
        if (ret != 0)
                rte_exit(EXIT_FAILURE,"CUSE device setup failure.\n");
 
-       init_virtio_net(&virtio_net_device_ops);
+       rte_vhost_driver_callback_register(&virtio_net_device_ops);
 
        /* Start CUSE session. */
-       start_cuse_session_loop();
+       rte_vhost_driver_session_start();
        return 0;
 
 }