Imported Upstream version 17.05

Change-Id: Id1e419c5a214e4a18739663b91f0f9a549f1fdc6
Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>

12 files changed, 1152 insertions, 565 deletions

diff --git a/lib/librte_vhost/Makefile b/lib/librte_vhost/Makefile
index 415ffc6e..4a116fe3 100644
--- a/lib/librte_vhost/Makefile
+++ b/lib/librte_vhost/Makefile
@@ -36,7 +36,7 @@ LIB = librte_vhost.a
 
 EXPORT_MAP := rte_vhost_version.map
 
-LIBABIVER := 3
+LIBABIVER := 4
 
 CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR) -O3 -D_FILE_OFFSET_BITS=64
 CFLAGS += -I vhost_user
@@ -51,13 +51,6 @@ SRCS-$(CONFIG_RTE_LIBRTE_VHOST) := fd_man.c socket.c vhost.c vhost_user.c \
 				   virtio_net.c
 
 # install includes
-SYMLINK-$(CONFIG_RTE_LIBRTE_VHOST)-include += rte_virtio_net.h
-
-# dependencies
-DEPDIRS-$(CONFIG_RTE_LIBRTE_VHOST) += lib/librte_eal
-DEPDIRS-$(CONFIG_RTE_LIBRTE_VHOST) += lib/librte_ether
-DEPDIRS-$(CONFIG_RTE_LIBRTE_VHOST) += lib/librte_mbuf
-DEPDIRS-$(CONFIG_RTE_LIBRTE_VHOST) += lib/librte_mempool
-DEPDIRS-$(CONFIG_RTE_LIBRTE_VHOST) += lib/librte_net
+SYMLINK-$(CONFIG_RTE_LIBRTE_VHOST)-include += rte_vhost.h
 
 include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/lib/librte_vhost/fd_man.c b/lib/librte_vhost/fd_man.c
index 8a075da2..2ceacc9a 100644
--- a/lib/librte_vhost/fd_man.c
+++ b/lib/librte_vhost/fd_man.c
@@ -65,17 +65,12 @@ fdset_move(struct fdset *pfdset, int dst, int src)
 	pfdset->rwfds[dst] = pfdset->rwfds[src];
 }
 
-/*
- * Find deleted fd entries and remove them
- */
 static void
-fdset_shrink(struct fdset *pfdset)
+fdset_shrink_nolock(struct fdset *pfdset)
 {
 	int i;
 	int last_valid_idx = get_last_valid_idx(pfdset, pfdset->num - 1);
 
-	pthread_mutex_lock(&pfdset->fd_mutex);
-
 	for (i = 0; i < last_valid_idx; i++) {
 		if (pfdset->fd[i].fd != -1)
 			continue;
@@ -84,7 +79,16 @@ fdset_shrink(struct fdset *pfdset)
 		last_valid_idx = get_last_valid_idx(pfdset, last_valid_idx - 1);
 	}
 	pfdset->num = last_valid_idx + 1;
+}
 
+/*
+ * Find deleted fd entries and remove them
+ */
+static void
+fdset_shrink(struct fdset *pfdset)
+{
+	pthread_mutex_lock(&pfdset->fd_mutex);
+	fdset_shrink_nolock(pfdset);
 	pthread_mutex_unlock(&pfdset->fd_mutex);
 }
 
@@ -151,8 +155,12 @@ fdset_add(struct fdset *pfdset, int fd, fd_cb rcb, fd_cb wcb, void *dat)
 	pthread_mutex_lock(&pfdset->fd_mutex);
 	i = pfdset->num < MAX_FDS ? pfdset->num++ : -1;
 	if (i == -1) {
-		pthread_mutex_unlock(&pfdset->fd_mutex);
-		return -2;
+		fdset_shrink_nolock(pfdset);
+		i = pfdset->num < MAX_FDS ? pfdset->num++ : -1;
+		if (i == -1) {
+			pthread_mutex_unlock(&pfdset->fd_mutex);
+			return -2;
+		}
 	}
 
 	fdset_add_fd(pfdset, i, fd, rcb, wcb, dat);
@@ -202,8 +210,8 @@ fdset_del(struct fdset *pfdset, int fd)
  * will wait until the flag is reset to zero(which indicates the callback is
  * finished), then it could free the context after fdset_del.
  */
-void
-fdset_event_dispatch(struct fdset *pfdset)
+void *
+fdset_event_dispatch(void *arg)
 {
 	int i;
 	struct pollfd *pfd;
@@ -213,9 +221,10 @@ fdset_event_dispatch(struct fdset *pfdset)
 	int fd, numfds;
 	int remove1, remove2;
 	int need_shrink;
+	struct fdset *pfdset = arg;
 
 	if (pfdset == NULL)
-		return;
+		return NULL;
 
 	while (1) {
 
@@ -286,4 +295,6 @@ fdset_event_dispatch(struct fdset *pfdset)
 		if (need_shrink)
 			fdset_shrink(pfdset);
 	}
+
+	return NULL;
 }
diff --git a/lib/librte_vhost/fd_man.h b/lib/librte_vhost/fd_man.h
index d319cac6..90d34db1 100644
--- a/lib/librte_vhost/fd_man.h
+++ b/lib/librte_vhost/fd_man.h
@@ -64,6 +64,6 @@ int fdset_add(struct fdset *pfdset, int fd,
 
 void *fdset_del(struct fdset *pfdset, int fd);
 
-void fdset_event_dispatch(struct fdset *pfdset);
+void *fdset_event_dispatch(void *arg);
 
 #endif
diff --git a/lib/librte_vhost/rte_vhost.h b/lib/librte_vhost/rte_vhost.h
new file mode 100644
index 00000000..605e47cb
--- /dev/null
+++ b/lib/librte_vhost/rte_vhost.h
@@ -0,0 +1,439 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2017 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _RTE_VHOST_H_
+#define _RTE_VHOST_H_
+
+/**
+ * @file
+ * Interface to vhost-user
+ */
+
+#include <stdint.h>
+#include <sys/eventfd.h>
+
+#include <rte_memory.h>
+#include <rte_mempool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* These are not C++-aware. */
+#include <linux/vhost.h>
+#include <linux/virtio_ring.h>
+
+#define RTE_VHOST_USER_CLIENT		(1ULL << 0)
+#define RTE_VHOST_USER_NO_RECONNECT	(1ULL << 1)
+#define RTE_VHOST_USER_DEQUEUE_ZERO_COPY	(1ULL << 2)
+
+/**
+ * Information relating to memory regions including offsets to
+ * addresses in QEMUs memory file.
+ */
+struct rte_vhost_mem_region {
+	uint64_t guest_phys_addr;
+	uint64_t guest_user_addr;
+	uint64_t host_user_addr;
+	uint64_t size;
+	void	 *mmap_addr;
+	uint64_t mmap_size;
+	int fd;
+};
+
+/**
+ * Memory structure includes region and mapping information.
+ */
+struct rte_vhost_memory {
+	uint32_t nregions;
+	struct rte_vhost_mem_region regions[];
+};
+
+struct rte_vhost_vring {
+	struct vring_desc	*desc;
+	struct vring_avail	*avail;
+	struct vring_used	*used;
+	uint64_t		log_guest_addr;
+
+	int			callfd;
+	int			kickfd;
+	uint16_t		size;
+};
+
+/**
+ * Device and vring operations.
+ */
+struct vhost_device_ops {
+	int (*new_device)(int vid);		/**< Add device. */
+	void (*destroy_device)(int vid);	/**< Remove device. */
+
+	int (*vring_state_changed)(int vid, uint16_t queue_id, int enable);	/**< triggered when a vring is enabled or disabled */
+
+	/**
+	 * Features could be changed after the feature negotiation.
+	 * For example, VHOST_F_LOG_ALL will be set/cleared at the
+	 * start/end of live migration, respectively. This callback
+	 * is used to inform the application on such change.
+	 */
+	int (*features_changed)(int vid, uint64_t features);
+
+	void *reserved[4]; /**< Reserved for future extension */
+};
+
+/**
+ * Convert guest physical address to host virtual address
+ *
+ * @param mem
+ *  the guest memory regions
+ * @param gpa
+ *  the guest physical address for querying
+ * @return
+ *  the host virtual address on success, 0 on failure
+ */
+static inline uint64_t __attribute__((always_inline))
+rte_vhost_gpa_to_vva(struct rte_vhost_memory *mem, uint64_t gpa)
+{
+	struct rte_vhost_mem_region *reg;
+	uint32_t i;
+
+	for (i = 0; i < mem->nregions; i++) {
+		reg = &mem->regions[i];
+		if (gpa >= reg->guest_phys_addr &&
+		    gpa <  reg->guest_phys_addr + reg->size) {
+			return gpa - reg->guest_phys_addr +
+			       reg->host_user_addr;
+		}
+	}
+
+	return 0;
+}
+
+#define RTE_VHOST_NEED_LOG(features)	((features) & (1ULL << VHOST_F_LOG_ALL))
+
+/**
+ * Log the memory write start with given address.
+ *
+ * This function only need be invoked when the live migration starts.
+ * Therefore, we won't need call it at all in the most of time. For
+ * making the performance impact be minimum, it's suggested to do a
+ * check before calling it:
+ *
+ *        if (unlikely(RTE_VHOST_NEED_LOG(features)))
+ *                rte_vhost_log_write(vid, addr, len);
+ *
+ * @param vid
+ *  vhost device ID
+ * @param addr
+ *  the starting address for write
+ * @param len
+ *  the length to write
+ */
+void rte_vhost_log_write(int vid, uint64_t addr, uint64_t len);
+
+/**
+ * Log the used ring update start at given offset.
+ *
+ * Same as rte_vhost_log_write, it's suggested to do a check before
+ * calling it:
+ *
+ *        if (unlikely(RTE_VHOST_NEED_LOG(features)))
+ *                rte_vhost_log_used_vring(vid, vring_idx, offset, len);
+ *
+ * @param vid
+ *  vhost device ID
+ * @param vring_idx
+ *  the vring index
+ * @param offset
+ *  the offset inside the used ring
+ * @param len
+ *  the length to write
+ */
+void rte_vhost_log_used_vring(int vid, uint16_t vring_idx,
+			      uint64_t offset, uint64_t len);
+
+int rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable);
+
+/**
+ * Register vhost driver. path could be different for multiple
+ * instance support.
+ */
+int rte_vhost_driver_register(const char *path, uint64_t flags);
+
+/* Unregister vhost driver. This is only meaningful to vhost user. */
+int rte_vhost_driver_unregister(const char *path);
+
+/**
+ * Set the feature bits the vhost-user driver supports.
+ *
+ * @param path
+ *  The vhost-user socket file path
+ * @param features
+ *  Supported features
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_driver_set_features(const char *path, uint64_t features);
+
+/**
+ * Enable vhost-user driver features.
+ *
+ * Note that
+ * - the param features should be a subset of the feature bits provided
+ *   by rte_vhost_driver_set_features().
+ * - it must be invoked before vhost-user negotiation starts.
+ *
+ * @param path
+ *  The vhost-user socket file path
+ * @param features
+ *  Features to enable
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_driver_enable_features(const char *path, uint64_t features);
+
+/**
+ * Disable vhost-user driver features.
+ *
+ * The two notes at rte_vhost_driver_enable_features() also apply here.
+ *
+ * @param path
+ *  The vhost-user socket file path
+ * @param features
+ *  Features to disable
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_driver_disable_features(const char *path, uint64_t features);
+
+/**
+ * Get the feature bits before feature negotiation.
+ *
+ * @param path
+ *  The vhost-user socket file path
+ * @param features
+ *  A pointer to store the queried feature bits
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_driver_get_features(const char *path, uint64_t *features);
+
+/**
+ * Get the feature bits after negotiation
+ *
+ * @param vid
+ *  Vhost device ID
+ * @param features
+ *  A pointer to store the queried feature bits
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_get_negotiated_features(int vid, uint64_t *features);
+
+/* Register callbacks. */
+int rte_vhost_driver_callback_register(const char *path,
+	struct vhost_device_ops const * const ops);
+
+/**
+ *
+ * Start the vhost-user driver.
+ *
+ * This function triggers the vhost-user negotiation.
+ *
+ * @param path
+ *  The vhost-user socket file path
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_driver_start(const char *path);
+
+/**
+ * Get the MTU value of the device if set in QEMU.
+ *
+ * @param vid
+ *  virtio-net device ID
+ * @param mtu
+ *  The variable to store the MTU value
+ *
+ * @return
+ *  0: success
+ *  -EAGAIN: device not yet started
+ *  -ENOTSUP: device does not support MTU feature
+ */
+int rte_vhost_get_mtu(int vid, uint16_t *mtu);
+
+/**
+ * Get the numa node from which the virtio net device's memory
+ * is allocated.
+ *
+ * @param vid
+ *  vhost device ID
+ *
+ * @return
+ *  The numa node, -1 on failure
+ */
+int rte_vhost_get_numa_node(int vid);
+
+/**
+ * @deprecated
+ * Get the number of queues the device supports.
+ *
+ * Note this function is deprecated, as it returns a queue pair number,
+ * which is vhost specific. Instead, rte_vhost_get_vring_num should
+ * be used.
+ *
+ * @param vid
+ *  vhost device ID
+ *
+ * @return
+ *  The number of queues, 0 on failure
+ */
+__rte_deprecated
+uint32_t rte_vhost_get_queue_num(int vid);
+
+/**
+ * Get the number of vrings the device supports.
+ *
+ * @param vid
+ *  vhost device ID
+ *
+ * @return
+ *  The number of vrings, 0 on failure
+ */
+uint16_t rte_vhost_get_vring_num(int vid);
+
+/**
+ * Get the virtio net device's ifname, which is the vhost-user socket
+ * file path.
+ *
+ * @param vid
+ *  vhost device ID
+ * @param buf
+ *  The buffer to stored the queried ifname
+ * @param len
+ *  The length of buf
+ *
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_get_ifname(int vid, char *buf, size_t len);
+
+/**
+ * Get how many avail entries are left in the queue
+ *
+ * @param vid
+ *  vhost device ID
+ * @param queue_id
+ *  virtio queue index
+ *
+ * @return
+ *  num of avail entires left
+ */
+uint16_t rte_vhost_avail_entries(int vid, uint16_t queue_id);
+
+struct rte_mbuf;
+struct rte_mempool;
+/**
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtual device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue.
+ * @param vid
+ *  vhost device ID
+ * @param queue_id
+ *  virtio queue index in mq case
+ * @param pkts
+ *  array to contain packets to be enqueued
+ * @param count
+ *  packets num to be enqueued
+ * @return
+ *  num of packets enqueued
+ */
+uint16_t rte_vhost_enqueue_burst(int vid, uint16_t queue_id,
+	struct rte_mbuf **pkts, uint16_t count);
+
+/**
+ * This function gets guest buffers from the virtio device TX virtqueue,
+ * construct host mbufs, copies guest buffer content to host mbufs and
+ * store them in pkts to be processed.
+ * @param vid
+ *  vhost device ID
+ * @param queue_id
+ *  virtio queue index in mq case
+ * @param mbuf_pool
+ *  mbuf_pool where host mbuf is allocated.
+ * @param pkts
+ *  array to contain packets to be dequeued
+ * @param count
+ *  packets num to be dequeued
+ * @return
+ *  num of packets dequeued
+ */
+uint16_t rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
+	struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count);
+
+/**
+ * Get guest mem table: a list of memory regions.
+ *
+ * An rte_vhost_vhost_memory object will be allocated internaly, to hold the
+ * guest memory regions. Application should free it at destroy_device()
+ * callback.
+ *
+ * @param vid
+ *  vhost device ID
+ * @param mem
+ *  To store the returned mem regions
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_get_mem_table(int vid, struct rte_vhost_memory **mem);
+
+/**
+ * Get guest vring info, including the vring address, vring size, etc.
+ *
+ * @param vid
+ *  vhost device ID
+ * @param vring_idx
+ *  vring index
+ * @param vring
+ *  the structure to hold the requested vring info
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_get_vhost_vring(int vid, uint16_t vring_idx,
+			      struct rte_vhost_vring *vring);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_VHOST_H_ */
diff --git a/lib/librte_vhost/rte_vhost_version.map b/lib/librte_vhost/rte_vhost_version.map
index 5ceaa8a5..07858732 100644
--- a/lib/librte_vhost/rte_vhost_version.map
+++ b/lib/librte_vhost/rte_vhost_version.map
@@ -4,12 +4,8 @@ DPDK_2.0 {
 	rte_vhost_dequeue_burst;
 	rte_vhost_driver_callback_register;
 	rte_vhost_driver_register;
-	rte_vhost_driver_session_start;
 	rte_vhost_enable_guest_notification;
 	rte_vhost_enqueue_burst;
-	rte_vhost_feature_disable;
-	rte_vhost_feature_enable;
-	rte_vhost_feature_get;
 
 	local: *;
 };
@@ -30,3 +26,22 @@ DPDK_16.07 {
 	rte_vhost_get_queue_num;
 
 } DPDK_2.1;
+
+DPDK_17.05 {
+	global:
+
+	rte_vhost_driver_disable_features;
+	rte_vhost_driver_enable_features;
+	rte_vhost_driver_get_features;
+	rte_vhost_driver_set_features;
+	rte_vhost_driver_start;
+	rte_vhost_get_mem_table;
+	rte_vhost_get_mtu;
+	rte_vhost_get_negotiated_features;
+	rte_vhost_get_vhost_vring;
+	rte_vhost_get_vring_num;
+	rte_vhost_gpa_to_vva;
+	rte_vhost_log_used_vring;
+	rte_vhost_log_write;
+
+} DPDK_16.07;
diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
deleted file mode 100644
index 926039c5..00000000
--- a/lib/librte_vhost/rte_virtio_net.h
+++ /dev/null
@@ -1,193 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _VIRTIO_NET_H_
-#define _VIRTIO_NET_H_
-
-/**
- * @file
- * Interface to vhost net
- */
-
-#include <stdint.h>
-#include <linux/vhost.h>
-#include <linux/virtio_ring.h>
-#include <linux/virtio_net.h>
-#include <sys/eventfd.h>
-#include <sys/socket.h>
-#include <linux/if.h>
-
-#include <rte_memory.h>
-#include <rte_mempool.h>
-#include <rte_ether.h>
-
-#define RTE_VHOST_USER_CLIENT		(1ULL << 0)
-#define RTE_VHOST_USER_NO_RECONNECT	(1ULL << 1)
-#define RTE_VHOST_USER_DEQUEUE_ZERO_COPY	(1ULL << 2)
-
-/* Enum for virtqueue management. */
-enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
-
-/**
- * Device and vring operations.
- */
-struct virtio_net_device_ops {
-	int (*new_device)(int vid);		/**< Add device. */
-	void (*destroy_device)(int vid);	/**< Remove device. */
-
-	int (*vring_state_changed)(int vid, uint16_t queue_id, int enable);	/**< triggered when a vring is enabled or disabled */
-
-	void *reserved[5]; /**< Reserved for future extension */
-};
-
-/**
- *  Disable features in feature_mask. Returns 0 on success.
- */
-int rte_vhost_feature_disable(uint64_t feature_mask);
-
-/**
- *  Enable features in feature_mask. Returns 0 on success.
- */
-int rte_vhost_feature_enable(uint64_t feature_mask);
-
-/* Returns currently supported vhost features */
-uint64_t rte_vhost_feature_get(void);
-
-int rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable);
-
-/**
- * Register vhost driver. path could be different for multiple
- * instance support.
- */
-int rte_vhost_driver_register(const char *path, uint64_t flags);
-
-/* Unregister vhost driver. This is only meaningful to vhost user. */
-int rte_vhost_driver_unregister(const char *path);
-
-/* Register callbacks. */
-int rte_vhost_driver_callback_register(struct virtio_net_device_ops const * const);
-/* Start vhost driver session blocking loop. */
-int rte_vhost_driver_session_start(void);
-
-/**
- * Get the numa node from which the virtio net device's memory
- * is allocated.
- *
- * @param vid
- *  virtio-net device ID
- *
- * @return
- *  The numa node, -1 on failure
- */
-int rte_vhost_get_numa_node(int vid);
-
-/**
- * Get the number of queues the device supports.
- *
- * @param vid
- *  virtio-net device ID
- *
- * @return
- *  The number of queues, 0 on failure
- */
-uint32_t rte_vhost_get_queue_num(int vid);
-
-/**
- * Get the virtio net device's ifname, which is the vhost-user socket
- * file path.
- *
- * @param vid
- *  virtio-net device ID
- * @param buf
- *  The buffer to stored the queried ifname
- * @param len
- *  The length of buf
- *
- * @return
- *  0 on success, -1 on failure
- */
-int rte_vhost_get_ifname(int vid, char *buf, size_t len);
-
-/**
- * Get how many avail entries are left in the queue
- *
- * @param vid
- *  virtio-net device ID
- * @param queue_id
- *  virtio queue index
- *
- * @return
- *  num of avail entires left
- */
-uint16_t rte_vhost_avail_entries(int vid, uint16_t queue_id);
-
-/**
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtual device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue.
- * @param vid
- *  virtio-net device ID
- * @param queue_id
- *  virtio queue index in mq case
- * @param pkts
- *  array to contain packets to be enqueued
- * @param count
- *  packets num to be enqueued
- * @return
- *  num of packets enqueued
- */
-uint16_t rte_vhost_enqueue_burst(int vid, uint16_t queue_id,
-	struct rte_mbuf **pkts, uint16_t count);
-
-/**
- * This function gets guest buffers from the virtio device TX virtqueue,
- * construct host mbufs, copies guest buffer content to host mbufs and
- * store them in pkts to be processed.
- * @param vid
- *  virtio-net device
- * @param queue_id
- *  virtio queue index in mq case
- * @param mbuf_pool
- *  mbuf_pool where host mbuf is allocated.
- * @param pkts
- *  array to contain packets to be dequeued
- * @param count
- *  packets num to be dequeued
- * @return
- *  num of packets dequeued
- */
-uint16_t rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
-	struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count);
-
-#endif /* _VIRTIO_NET_H_ */
diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c
index aaa9c270..c7f99b08 100644
--- a/lib/librte_vhost/socket.c
+++ b/lib/librte_vhost/socket.c
@@ -52,22 +52,42 @@
 #include "vhost.h"
 #include "vhost_user.h"
 
+
+TAILQ_HEAD(vhost_user_connection_list, vhost_user_connection);
+
 /*
  * Every time rte_vhost_driver_register() is invoked, an associated
  * vhost_user_socket struct will be created.
  */
 struct vhost_user_socket {
+	struct vhost_user_connection_list conn_list;
+	pthread_mutex_t conn_mutex;
 	char *path;
-	int listenfd;
-	int connfd;
+	int socket_fd;
+	struct sockaddr_un un;
 	bool is_server;
 	bool reconnect;
 	bool dequeue_zero_copy;
+
+	/*
+	 * The "supported_features" indicates the feature bits the
+	 * vhost driver supports. The "features" indicates the feature
+	 * bits after the rte_vhost_driver_features_disable/enable().
+	 * It is also the final feature bits used for vhost-user
+	 * features negotiation.
+	 */
+	uint64_t supported_features;
+	uint64_t features;
+
+	struct vhost_device_ops const *notify_ops;
 };
 
 struct vhost_user_connection {
 	struct vhost_user_socket *vsocket;
+	int connfd;
 	int vid;
+
+	TAILQ_ENTRY(vhost_user_connection) next;
 };
 
 #define MAX_VHOST_SOCKET 1024
@@ -82,7 +102,8 @@ struct vhost_user {
 
 static void vhost_user_server_new_connection(int fd, void *data, int *remove);
 static void vhost_user_read_cb(int fd, void *dat, int *remove);
-static int vhost_user_create_client(struct vhost_user_socket *vsocket);
+static int create_unix_socket(struct vhost_user_socket *vsocket);
+static int vhost_user_start_client(struct vhost_user_socket *vsocket);
 
 static struct vhost_user vhost_user = {
 	.fdset = {
@@ -209,19 +230,24 @@ vhost_user_add_connection(int fd, struct vhost_user_socket *vsocket)
 
 	RTE_LOG(INFO, VHOST_CONFIG, "new device, handle is %d\n", vid);
 
-	vsocket->connfd = fd;
+	conn->connfd = fd;
 	conn->vsocket = vsocket;
 	conn->vid = vid;
 	ret = fdset_add(&vhost_user.fdset, fd, vhost_user_read_cb,
 			NULL, conn);
 	if (ret < 0) {
-		vsocket->connfd = -1;
+		conn->connfd = -1;
 		free(conn);
 		close(fd);
 		RTE_LOG(ERR, VHOST_CONFIG,
 			"failed to add fd %d into vhost server fdset\n",
 			fd);
+		return;
 	}
+
+	pthread_mutex_lock(&vsocket->conn_mutex);
+	TAILQ_INSERT_TAIL(&vsocket->conn_list, conn, next);
+	pthread_mutex_unlock(&vsocket->conn_mutex);
 }
 
 /* call back when there is new vhost-user connection from client  */
@@ -247,29 +273,36 @@ vhost_user_read_cb(int connfd, void *dat, int *remove)
 
 	ret = vhost_user_msg_handler(conn->vid, connfd);
 	if (ret < 0) {
-		vsocket->connfd = -1;
 		close(connfd);
 		*remove = 1;
 		vhost_destroy_device(conn->vid);
+
+		pthread_mutex_lock(&vsocket->conn_mutex);
+		TAILQ_REMOVE(&vsocket->conn_list, conn, next);
+		pthread_mutex_unlock(&vsocket->conn_mutex);
+
 		free(conn);
 
-		if (vsocket->reconnect)
-			vhost_user_create_client(vsocket);
+		if (vsocket->reconnect) {
+			create_unix_socket(vsocket);
+			vhost_user_start_client(vsocket);
+		}
 	}
 }
 
 static int
-create_unix_socket(const char *path, struct sockaddr_un *un, bool is_server)
+create_unix_socket(struct vhost_user_socket *vsocket)
 {
 	int fd;
+	struct sockaddr_un *un = &vsocket->un;
 
 	fd = socket(AF_UNIX, SOCK_STREAM, 0);
 	if (fd < 0)
 		return -1;
 	RTE_LOG(INFO, VHOST_CONFIG, "vhost-user %s: socket created, fd: %d\n",
-		is_server ? "server" : "client", fd);
+		vsocket->is_server ? "server" : "client", fd);
 
-	if (!is_server && fcntl(fd, F_SETFL, O_NONBLOCK)) {
+	if (!vsocket->is_server && fcntl(fd, F_SETFL, O_NONBLOCK)) {
 		RTE_LOG(ERR, VHOST_CONFIG,
 			"vhost-user: can't set nonblocking mode for socket, fd: "
 			"%d (%s)\n", fd, strerror(errno));
@@ -279,25 +312,21 @@ create_unix_socket(const char *path, struct sockaddr_un *un, bool is_server)
 
 	memset(un, 0, sizeof(*un));
 	un->sun_family = AF_UNIX;
-	strncpy(un->sun_path, path, sizeof(un->sun_path));
+	strncpy(un->sun_path, vsocket->path, sizeof(un->sun_path));
 	un->sun_path[sizeof(un->sun_path) - 1] = '\0';
 
-	return fd;
+	vsocket->socket_fd = fd;
+	return 0;
 }
 
 static int
-vhost_user_create_server(struct vhost_user_socket *vsocket)
+vhost_user_start_server(struct vhost_user_socket *vsocket)
 {
-	int fd;
 	int ret;
-	struct sockaddr_un un;
+	int fd = vsocket->socket_fd;
 	const char *path = vsocket->path;
 
-	fd = create_unix_socket(path, &un, vsocket->is_server);
-	if (fd < 0)
-		return -1;
-
-	ret = bind(fd, (struct sockaddr *)&un, sizeof(un));
+	ret = bind(fd, (struct sockaddr *)&vsocket->un, sizeof(vsocket->un));
 	if (ret < 0) {
 		RTE_LOG(ERR, VHOST_CONFIG,
 			"failed to bind to %s: %s; remove it and try again\n",
@@ -310,7 +339,6 @@ vhost_user_create_server(struct vhost_user_socket *vsocket)
 	if (ret < 0)
 		goto err;
 
-	vsocket->listenfd = fd;
 	ret = fdset_add(&vhost_user.fdset, fd, vhost_user_server_new_connection,
 		  NULL, vsocket);
 	if (ret < 0) {
@@ -429,26 +457,21 @@ vhost_user_reconnect_init(void)
 }
 
 static int
-vhost_user_create_client(struct vhost_user_socket *vsocket)
+vhost_user_start_client(struct vhost_user_socket *vsocket)
 {
-	int fd;
 	int ret;
-	struct sockaddr_un un;
+	int fd = vsocket->socket_fd;
 	const char *path = vsocket->path;
 	struct vhost_user_reconnect *reconn;
 
-	fd = create_unix_socket(path, &un, vsocket->is_server);
-	if (fd < 0)
-		return -1;
-
-	ret = vhost_user_connect_nonblock(fd, (struct sockaddr *)&un,
-					  sizeof(un));
+	ret = vhost_user_connect_nonblock(fd, (struct sockaddr *)&vsocket->un,
+					  sizeof(vsocket->un));
 	if (ret == 0) {
 		vhost_user_add_connection(fd, vsocket);
 		return 0;
 	}
 
-	RTE_LOG(ERR, VHOST_CONFIG,
+	RTE_LOG(WARNING, VHOST_CONFIG,
 		"failed to connect to %s: %s\n",
 		path, strerror(errno));
 
@@ -457,7 +480,7 @@ vhost_user_create_client(struct vhost_user_socket *vsocket)
 		return -1;
 	}
 
-	RTE_LOG(ERR, VHOST_CONFIG, "%s: reconnecting...\n", path);
+	RTE_LOG(INFO, VHOST_CONFIG, "%s: reconnecting...\n", path);
 	reconn = malloc(sizeof(*reconn));
 	if (reconn == NULL) {
 		RTE_LOG(ERR, VHOST_CONFIG,
@@ -465,7 +488,7 @@ vhost_user_create_client(struct vhost_user_socket *vsocket)
 		close(fd);
 		return -1;
 	}
-	reconn->un = un;
+	reconn->un = vsocket->un;
 	reconn->fd = fd;
 	reconn->vsocket = vsocket;
 	pthread_mutex_lock(&reconn_list.mutex);
@@ -475,6 +498,94 @@ vhost_user_create_client(struct vhost_user_socket *vsocket)
 	return 0;
 }
 
+static struct vhost_user_socket *
+find_vhost_user_socket(const char *path)
+{
+	int i;
+
+	for (i = 0; i < vhost_user.vsocket_cnt; i++) {
+		struct vhost_user_socket *vsocket = vhost_user.vsockets[i];
+
+		if (!strcmp(vsocket->path, path))
+			return vsocket;
+	}
+
+	return NULL;
+}
+
+int
+rte_vhost_driver_disable_features(const char *path, uint64_t features)
+{
+	struct vhost_user_socket *vsocket;
+
+	pthread_mutex_lock(&vhost_user.mutex);
+	vsocket = find_vhost_user_socket(path);
+	if (vsocket)
+		vsocket->features &= ~features;
+	pthread_mutex_unlock(&vhost_user.mutex);
+
+	return vsocket ? 0 : -1;
+}
+
+int
+rte_vhost_driver_enable_features(const char *path, uint64_t features)
+{
+	struct vhost_user_socket *vsocket;
+
+	pthread_mutex_lock(&vhost_user.mutex);
+	vsocket = find_vhost_user_socket(path);
+	if (vsocket) {
+		if ((vsocket->supported_features & features) != features) {
+			/*
+			 * trying to enable features the driver doesn't
+			 * support.
+			 */
+			pthread_mutex_unlock(&vhost_user.mutex);
+			return -1;
+		}
+		vsocket->features |= features;
+	}
+	pthread_mutex_unlock(&vhost_user.mutex);
+
+	return vsocket ? 0 : -1;
+}
+
+int
+rte_vhost_driver_set_features(const char *path, uint64_t features)
+{
+	struct vhost_user_socket *vsocket;
+
+	pthread_mutex_lock(&vhost_user.mutex);
+	vsocket = find_vhost_user_socket(path);
+	if (vsocket) {
+		vsocket->supported_features = features;
+		vsocket->features = features;
+	}
+	pthread_mutex_unlock(&vhost_user.mutex);
+
+	return vsocket ? 0 : -1;
+}
+
+int
+rte_vhost_driver_get_features(const char *path, uint64_t *features)
+{
+	struct vhost_user_socket *vsocket;
+
+	pthread_mutex_lock(&vhost_user.mutex);
+	vsocket = find_vhost_user_socket(path);
+	if (vsocket)
+		*features = vsocket->features;
+	pthread_mutex_unlock(&vhost_user.mutex);
+
+	if (!vsocket) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"socket file %s is not registered yet.\n", path);
+		return -1;
+	} else {
+		return 0;
+	}
+}
+
 /*
  * Register a new vhost-user socket; here we could act as server
  * (the default case), or client (when RTE_VHOST_USER_CLIENT) flag
@@ -502,9 +613,25 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
 		goto out;
 	memset(vsocket, 0, sizeof(struct vhost_user_socket));
 	vsocket->path = strdup(path);
-	vsocket->connfd = -1;
+	TAILQ_INIT(&vsocket->conn_list);
+	pthread_mutex_init(&vsocket->conn_mutex, NULL);
 	vsocket->dequeue_zero_copy = flags & RTE_VHOST_USER_DEQUEUE_ZERO_COPY;
 
+	/*
+	 * Set the supported features correctly for the builtin vhost-user
+	 * net driver.
+	 *
+	 * Applications know nothing about features the builtin virtio net
+	 * driver (virtio_net.c) supports, thus it's not possible for them
+	 * to invoke rte_vhost_driver_set_features(). To workaround it, here
+	 * we set it unconditionally. If the application want to implement
+	 * another vhost-user driver (say SCSI), it should call the
+	 * rte_vhost_driver_set_features(), which will overwrite following
+	 * two values.
+	 */
+	vsocket->supported_features = VIRTIO_NET_SUPPORTED_FEATURES;
+	vsocket->features           = VIRTIO_NET_SUPPORTED_FEATURES;
+
 	if ((flags & RTE_VHOST_USER_CLIENT) != 0) {
 		vsocket->reconnect = !(flags & RTE_VHOST_USER_NO_RECONNECT);
 		if (vsocket->reconnect && reconn_tid == 0) {
@@ -514,11 +641,10 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
 				goto out;
 			}
 		}
-		ret = vhost_user_create_client(vsocket);
 	} else {
 		vsocket->is_server = true;
-		ret = vhost_user_create_server(vsocket);
 	}
+	ret = create_unix_socket(vsocket);
 	if (ret < 0) {
 		free(vsocket->path);
 		free(vsocket);
@@ -565,7 +691,7 @@ rte_vhost_driver_unregister(const char *path)
 {
 	int i;
 	int count;
-	struct vhost_user_connection *conn;
+	struct vhost_user_connection *conn, *next;
 
 	pthread_mutex_lock(&vhost_user.mutex);
 
@@ -574,22 +700,29 @@ rte_vhost_driver_unregister(const char *path)
 
 		if (!strcmp(vsocket->path, path)) {
 			if (vsocket->is_server) {
-				fdset_del(&vhost_user.fdset, vsocket->listenfd);
-				close(vsocket->listenfd);
+				fdset_del(&vhost_user.fdset, vsocket->socket_fd);
+				close(vsocket->socket_fd);
 				unlink(path);
 			} else if (vsocket->reconnect) {
 				vhost_user_remove_reconnect(vsocket);
 			}
 
-			conn = fdset_del(&vhost_user.fdset, vsocket->connfd);
-			if (conn) {
+			pthread_mutex_lock(&vsocket->conn_mutex);
+			for (conn = TAILQ_FIRST(&vsocket->conn_list);
+			     conn != NULL;
+			     conn = next) {
+				next = TAILQ_NEXT(conn, next);
+
+				fdset_del(&vhost_user.fdset, conn->connfd);
 				RTE_LOG(INFO, VHOST_CONFIG,
 					"free connfd = %d for device '%s'\n",
-					vsocket->connfd, path);
-				close(vsocket->connfd);
+					conn->connfd, path);
+				close(conn->connfd);
 				vhost_destroy_device(conn->vid);
+				TAILQ_REMOVE(&vsocket->conn_list, conn, next);
 				free(conn);
 			}
+			pthread_mutex_unlock(&vsocket->conn_mutex);
 
 			free(vsocket->path);
 			free(vsocket);
@@ -607,9 +740,59 @@ rte_vhost_driver_unregister(const char *path)
 	return -1;
 }
 
+/*
+ * Register ops so that we can add/remove device to data core.
+ */
+int
+rte_vhost_driver_callback_register(const char *path,
+	struct vhost_device_ops const * const ops)
+{
+	struct vhost_user_socket *vsocket;
+
+	pthread_mutex_lock(&vhost_user.mutex);
+	vsocket = find_vhost_user_socket(path);
+	if (vsocket)
+		vsocket->notify_ops = ops;
+	pthread_mutex_unlock(&vhost_user.mutex);
+
+	return vsocket ? 0 : -1;
+}
+
+struct vhost_device_ops const *
+vhost_driver_callback_get(const char *path)
+{
+	struct vhost_user_socket *vsocket;
+
+	pthread_mutex_lock(&vhost_user.mutex);
+	vsocket = find_vhost_user_socket(path);
+	pthread_mutex_unlock(&vhost_user.mutex);
+
+	return vsocket ? vsocket->notify_ops : NULL;
+}
+
 int
-rte_vhost_driver_session_start(void)
+rte_vhost_driver_start(const char *path)
 {
-	fdset_event_dispatch(&vhost_user.fdset);
-	return 0;
+	struct vhost_user_socket *vsocket;
+	static pthread_t fdset_tid;
+
+	pthread_mutex_lock(&vhost_user.mutex);
+	vsocket = find_vhost_user_socket(path);
+	pthread_mutex_unlock(&vhost_user.mutex);
+
+	if (!vsocket)
+		return -1;
+
+	if (fdset_tid == 0) {
+		int ret = pthread_create(&fdset_tid, NULL, fdset_event_dispatch,
+				     &vhost_user.fdset);
+		if (ret < 0)
+			RTE_LOG(ERR, VHOST_CONFIG,
+				"failed to create fdset handling thread");
+	}
+
+	if (vsocket->is_server)
+		return vhost_user_start_server(vsocket);
+	else
+		return vhost_user_start_client(vsocket);
 }
diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index e4150934..0b19d2eb 100644
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -45,36 +45,12 @@
 #include <rte_string_fns.h>
 #include <rte_memory.h>
 #include <rte_malloc.h>
-#include <rte_virtio_net.h>
+#include <rte_vhost.h>
 
 #include "vhost.h"
 
-#define VHOST_USER_F_PROTOCOL_FEATURES	30
-
-/* Features supported by this lib. */
-#define VHOST_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
-				(1ULL << VIRTIO_NET_F_CTRL_VQ) | \
-				(1ULL << VIRTIO_NET_F_CTRL_RX) | \
-				(1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE) | \
-				(VHOST_SUPPORTS_MQ)            | \
-				(1ULL << VIRTIO_F_VERSION_1)   | \
-				(1ULL << VHOST_F_LOG_ALL)      | \
-				(1ULL << VHOST_USER_F_PROTOCOL_FEATURES) | \
-				(1ULL << VIRTIO_NET_F_HOST_TSO4) | \
-				(1ULL << VIRTIO_NET_F_HOST_TSO6) | \
-				(1ULL << VIRTIO_NET_F_CSUM)    | \
-				(1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
-				(1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
-				(1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
-				(1ULL << VIRTIO_RING_F_INDIRECT_DESC))
-
-uint64_t VHOST_FEATURES = VHOST_SUPPORTED_FEATURES;
-
 struct virtio_net *vhost_devices[MAX_VHOST_DEVICE];
 
-/* device ops to add/remove device to/from data core. */
-struct virtio_net_device_ops const *notify_ops;
-
 struct virtio_net *
 get_device(int vid)
 {
@@ -108,10 +84,8 @@ cleanup_device(struct virtio_net *dev, int destroy)
 
 	vhost_backend_cleanup(dev);
 
-	for (i = 0; i < dev->virt_qp_nb; i++) {
-		cleanup_vq(dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_RXQ], destroy);
-		cleanup_vq(dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_TXQ], destroy);
-	}
+	for (i = 0; i < dev->nr_vring; i++)
+		cleanup_vq(dev->virtqueue[i], destroy);
 }
 
 /*
@@ -121,24 +95,21 @@ static void
 free_device(struct virtio_net *dev)
 {
 	uint32_t i;
-	struct vhost_virtqueue *rxq, *txq;
+	struct vhost_virtqueue *vq;
 
-	for (i = 0; i < dev->virt_qp_nb; i++) {
-		rxq = dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_RXQ];
-		txq = dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_TXQ];
+	for (i = 0; i < dev->nr_vring; i++) {
+		vq = dev->virtqueue[i];
 
-		rte_free(rxq->shadow_used_ring);
-		rte_free(txq->shadow_used_ring);
+		rte_free(vq->shadow_used_ring);
 
-		/* rxq and txq are allocated together as queue-pair */
-		rte_free(rxq);
+		rte_free(vq);
 	}
 
 	rte_free(dev);
 }
 
 static void
-init_vring_queue(struct vhost_virtqueue *vq, int qp_idx)
+init_vring_queue(struct vhost_virtqueue *vq)
 {
 	memset(vq, 0, sizeof(struct vhost_virtqueue));
 
@@ -148,69 +119,48 @@ init_vring_queue(struct vhost_virtqueue *vq, int qp_idx)
 	/* Backends are set to -1 indicating an inactive device. */
 	vq->backend = -1;
 
-	/* always set the default vq pair to enabled */
-	if (qp_idx == 0)
-		vq->enabled = 1;
+	/*
+	 * always set the vq to enabled; this is to keep compatibility
+	 * with the old QEMU, whereas there is no SET_VRING_ENABLE message.
+	 */
+	vq->enabled = 1;
 
 	TAILQ_INIT(&vq->zmbuf_list);
 }
 
 static void
-init_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
-{
-	uint32_t base_idx = qp_idx * VIRTIO_QNUM;
-
-	init_vring_queue(dev->virtqueue[base_idx + VIRTIO_RXQ], qp_idx);
-	init_vring_queue(dev->virtqueue[base_idx + VIRTIO_TXQ], qp_idx);
-}
-
-static void
-reset_vring_queue(struct vhost_virtqueue *vq, int qp_idx)
+reset_vring_queue(struct vhost_virtqueue *vq)
 {
 	int callfd;
 
 	callfd = vq->callfd;
-	init_vring_queue(vq, qp_idx);
+	init_vring_queue(vq);
 	vq->callfd = callfd;
 }
 
-static void
-reset_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
-{
-	uint32_t base_idx = qp_idx * VIRTIO_QNUM;
-
-	reset_vring_queue(dev->virtqueue[base_idx + VIRTIO_RXQ], qp_idx);
-	reset_vring_queue(dev->virtqueue[base_idx + VIRTIO_TXQ], qp_idx);
-}
-
 int
-alloc_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
+alloc_vring_queue(struct virtio_net *dev, uint32_t vring_idx)
 {
-	struct vhost_virtqueue *virtqueue = NULL;
-	uint32_t virt_rx_q_idx = qp_idx * VIRTIO_QNUM + VIRTIO_RXQ;
-	uint32_t virt_tx_q_idx = qp_idx * VIRTIO_QNUM + VIRTIO_TXQ;
+	struct vhost_virtqueue *vq;
 
-	virtqueue = rte_malloc(NULL,
-			       sizeof(struct vhost_virtqueue) * VIRTIO_QNUM, 0);
-	if (virtqueue == NULL) {
+	vq = rte_malloc(NULL, sizeof(struct vhost_virtqueue), 0);
+	if (vq == NULL) {
 		RTE_LOG(ERR, VHOST_CONFIG,
-			"Failed to allocate memory for virt qp:%d.\n", qp_idx);
+			"Failed to allocate memory for vring:%u.\n", vring_idx);
 		return -1;
 	}
 
-	dev->virtqueue[virt_rx_q_idx] = virtqueue;
-	dev->virtqueue[virt_tx_q_idx] = virtqueue + VIRTIO_TXQ;
-
-	init_vring_queue_pair(dev, qp_idx);
+	dev->virtqueue[vring_idx] = vq;
+	init_vring_queue(vq);
 
-	dev->virt_qp_nb += 1;
+	dev->nr_vring += 1;
 
 	return 0;
 }
 
 /*
  * Reset some variables in device structure, while keeping few
- * others untouched, such as vid, ifname, virt_qp_nb: they
+ * others untouched, such as vid, ifname, nr_vring: they
  * should be same unless the device is removed.
  */
 void
@@ -222,8 +172,8 @@ reset_device(struct virtio_net *dev)
 	dev->protocol_features = 0;
 	dev->flags = 0;
 
-	for (i = 0; i < dev->virt_qp_nb; i++)
-		reset_vring_queue_pair(dev, i);
+	for (i = 0; i < dev->nr_vring; i++)
+		reset_vring_queue(dev->virtqueue[i]);
 }
 
 /*
@@ -274,7 +224,7 @@ vhost_destroy_device(int vid)
 
 	if (dev->flags & VIRTIO_DEV_RUNNING) {
 		dev->flags &= ~VIRTIO_DEV_RUNNING;
-		notify_ops->destroy_device(vid);
+		dev->notify_ops->destroy_device(vid);
 	}
 
 	cleanup_device(dev, 1);
@@ -312,6 +262,25 @@ vhost_enable_dequeue_zero_copy(int vid)
 }
 
 int
+rte_vhost_get_mtu(int vid, uint16_t *mtu)
+{
+	struct virtio_net *dev = get_device(vid);
+
+	if (!dev)
+		return -ENODEV;
+
+	if (!(dev->flags & VIRTIO_DEV_READY))
+		return -EAGAIN;
+
+	if (!(dev->features & VIRTIO_NET_F_MTU))
+		return -ENOTSUP;
+
+	*mtu = dev->mtu;
+
+	return 0;
+}
+
+int
 rte_vhost_get_numa_node(int vid)
 {
 #ifdef RTE_LIBRTE_VHOST_NUMA
@@ -345,7 +314,18 @@ rte_vhost_get_queue_num(int vid)
 	if (dev == NULL)
 		return 0;
 
-	return dev->virt_qp_nb;
+	return dev->nr_vring / 2;
+}
+
+uint16_t
+rte_vhost_get_vring_num(int vid)
+{
+	struct virtio_net *dev = get_device(vid);
+
+	if (dev == NULL)
+		return 0;
+
+	return dev->nr_vring;
 }
 
 int
@@ -364,6 +344,72 @@ rte_vhost_get_ifname(int vid, char *buf, size_t len)
 	return 0;
 }
 
+int
+rte_vhost_get_negotiated_features(int vid, uint64_t *features)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(vid);
+	if (!dev)
+		return -1;
+
+	*features = dev->features;
+	return 0;
+}
+
+int
+rte_vhost_get_mem_table(int vid, struct rte_vhost_memory **mem)
+{
+	struct virtio_net *dev;
+	struct rte_vhost_memory *m;
+	size_t size;
+
+	dev = get_device(vid);
+	if (!dev)
+		return -1;
+
+	size = dev->mem->nregions * sizeof(struct rte_vhost_mem_region);
+	m = malloc(size);
+	if (!m)
+		return -1;
+
+	m->nregions = dev->mem->nregions;
+	memcpy(m->regions, dev->mem->regions, size);
+	*mem = m;
+
+	return 0;
+}
+
+int
+rte_vhost_get_vhost_vring(int vid, uint16_t vring_idx,
+			  struct rte_vhost_vring *vring)
+{
+	struct virtio_net *dev;
+	struct vhost_virtqueue *vq;
+
+	dev = get_device(vid);
+	if (!dev)
+		return -1;
+
+	if (vring_idx >= VHOST_MAX_VRING)
+		return -1;
+
+	vq = dev->virtqueue[vring_idx];
+	if (!vq)
+		return -1;
+
+	vring->desc  = vq->desc;
+	vring->avail = vq->avail;
+	vring->used  = vq->used;
+	vring->log_guest_addr  = vq->log_guest_addr;
+
+	vring->callfd  = vq->callfd;
+	vring->kickfd  = vq->kickfd;
+	vring->size    = vq->size;
+
+	return 0;
+}
+
 uint16_t
 rte_vhost_avail_entries(int vid, uint16_t queue_id)
 {
@@ -399,33 +445,33 @@ rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable)
 	return 0;
 }
 
-uint64_t rte_vhost_feature_get(void)
+void
+rte_vhost_log_write(int vid, uint64_t addr, uint64_t len)
 {
-	return VHOST_FEATURES;
-}
+	struct virtio_net *dev = get_device(vid);
 
-int rte_vhost_feature_disable(uint64_t feature_mask)
-{
-	VHOST_FEATURES = VHOST_FEATURES & ~feature_mask;
-	return 0;
-}
+	if (dev == NULL)
+		return;
 
-int rte_vhost_feature_enable(uint64_t feature_mask)
-{
-	if ((feature_mask & VHOST_SUPPORTED_FEATURES) == feature_mask) {
-		VHOST_FEATURES = VHOST_FEATURES | feature_mask;
-		return 0;
-	}
-	return -1;
+	vhost_log_write(dev, addr, len);
 }
 
-/*
- * Register ops so that we can add/remove device to data core.
- */
-int
-rte_vhost_driver_callback_register(struct virtio_net_device_ops const * const ops)
+void
+rte_vhost_log_used_vring(int vid, uint16_t vring_idx,
+			 uint64_t offset, uint64_t len)
 {
-	notify_ops = ops;
+	struct virtio_net *dev;
+	struct vhost_virtqueue *vq;
 
-	return 0;
+	dev = get_device(vid);
+	if (dev == NULL)
+		return;
+
+	if (vring_idx >= VHOST_MAX_VRING)
+		return;
+	vq = dev->virtqueue[vring_idx];
+	if (!vq)
+		return;
+
+	vhost_log_used_vring(dev, vq, offset, len);
 }
diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 22564f1c..ddd8a9c4 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -39,13 +39,19 @@
 #include <sys/queue.h>
 #include <unistd.h>
 #include <linux/vhost.h>
+#include <linux/virtio_net.h>
+#include <sys/socket.h>
+#include <linux/if.h>
 
 #include <rte_log.h>
+#include <rte_ether.h>
 
-#include "rte_virtio_net.h"
+#include "rte_vhost.h"
 
 /* Used to indicate that the device is running on a data core */
 #define VIRTIO_DEV_RUNNING 1
+/* Used to indicate that the device is ready to operate */
+#define VIRTIO_DEV_READY 2
 
 /* Backend value set by guest. */
 #define VIRTIO_DEV_STOPPED -1
@@ -110,24 +116,20 @@ struct vhost_virtqueue {
 	uint16_t                shadow_used_idx;
 } __rte_cache_aligned;
 
-/* Old kernels have no such macro defined */
+/* Old kernels have no such macros defined */
 #ifndef VIRTIO_NET_F_GUEST_ANNOUNCE
  #define VIRTIO_NET_F_GUEST_ANNOUNCE 21
 #endif
 
+#ifndef VIRTIO_NET_F_MQ
+ #define VIRTIO_NET_F_MQ		22
+#endif
 
-/*
- * Make an extra wrapper for VIRTIO_NET_F_MQ and
- * VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX as they are
- * introduced since kernel v3.8. This makes our
- * code buildable for older kernel.
- */
-#ifdef VIRTIO_NET_F_MQ
- #define VHOST_MAX_QUEUE_PAIRS	VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX
- #define VHOST_SUPPORTS_MQ	(1ULL << VIRTIO_NET_F_MQ)
-#else
- #define VHOST_MAX_QUEUE_PAIRS	1
- #define VHOST_SUPPORTS_MQ	0
+#define VHOST_MAX_VRING			0x100
+#define VHOST_MAX_QUEUE_PAIRS		0x80
+
+#ifndef VIRTIO_NET_F_MTU
+ #define VIRTIO_NET_F_MTU 3
 #endif
 
 /*
@@ -137,6 +139,27 @@ struct vhost_virtqueue {
  #define VIRTIO_F_VERSION_1 32
 #endif
 
+#define VHOST_USER_F_PROTOCOL_FEATURES	30
+
+/* Features supported by this builtin vhost-user net driver. */
+#define VIRTIO_NET_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
+				(1ULL << VIRTIO_NET_F_CTRL_VQ) | \
+				(1ULL << VIRTIO_NET_F_CTRL_RX) | \
+				(1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE) | \
+				(1ULL << VIRTIO_NET_F_MQ)      | \
+				(1ULL << VIRTIO_F_VERSION_1)   | \
+				(1ULL << VHOST_F_LOG_ALL)      | \
+				(1ULL << VHOST_USER_F_PROTOCOL_FEATURES) | \
+				(1ULL << VIRTIO_NET_F_HOST_TSO4) | \
+				(1ULL << VIRTIO_NET_F_HOST_TSO6) | \
+				(1ULL << VIRTIO_NET_F_CSUM)    | \
+				(1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
+				(1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
+				(1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
+				(1ULL << VIRTIO_RING_F_INDIRECT_DESC) | \
+				(1ULL << VIRTIO_NET_F_MTU))
+
+
 struct guest_page {
 	uint64_t guest_phys_addr;
 	uint64_t host_phys_addr;
@@ -149,7 +172,7 @@ struct guest_page {
  */
 struct virtio_net {
 	/* Frontend (QEMU) memory and memory region information */
-	struct virtio_memory	*mem;
+	struct rte_vhost_memory	*mem;
 	uint64_t		features;
 	uint64_t		protocol_features;
 	int			vid;
@@ -157,7 +180,7 @@ struct virtio_net {
 	uint16_t		vhost_hlen;
 	/* to tell if we need broadcast rarp packet */
 	rte_atomic16_t		broadcast_rarp;
-	uint32_t		virt_qp_nb;
+	uint32_t		nr_vring;
 	int			dequeue_zero_copy;
 	struct vhost_virtqueue	*virtqueue[VHOST_MAX_QUEUE_PAIRS * 2];
 #define IF_NAME_SZ (PATH_MAX > IFNAMSIZ ? PATH_MAX : IFNAMSIZ)
@@ -166,35 +189,52 @@ struct virtio_net {
 	uint64_t		log_base;
 	uint64_t		log_addr;
 	struct ether_addr	mac;
+	uint16_t		mtu;
+
+	struct vhost_device_ops const *notify_ops;
 
 	uint32_t		nr_guest_pages;
 	uint32_t		max_guest_pages;
 	struct guest_page       *guest_pages;
 } __rte_cache_aligned;
 
-/**
- * Information relating to memory regions including offsets to
- * addresses in QEMUs memory file.
- */
-struct virtio_memory_region {
-	uint64_t guest_phys_addr;
-	uint64_t guest_user_addr;
-	uint64_t host_user_addr;
-	uint64_t size;
-	void	 *mmap_addr;
-	uint64_t mmap_size;
-	int fd;
-};
 
+#define VHOST_LOG_PAGE	4096
 
-/**
- * Memory structure includes region and mapping information.
- */
-struct virtio_memory {
-	uint32_t nregions;
-	struct virtio_memory_region regions[0];
-};
+static inline void __attribute__((always_inline))
+vhost_log_page(uint8_t *log_base, uint64_t page)
+{
+	log_base[page / 8] |= 1 << (page % 8);
+}
+
+static inline void __attribute__((always_inline))
+vhost_log_write(struct virtio_net *dev, uint64_t addr, uint64_t len)
+{
+	uint64_t page;
+
+	if (likely(((dev->features & (1ULL << VHOST_F_LOG_ALL)) == 0) ||
+		   !dev->log_base || !len))
+		return;
+
+	if (unlikely(dev->log_size <= ((addr + len - 1) / VHOST_LOG_PAGE / 8)))
+		return;
+
+	/* To make sure guest memory updates are committed before logging */
+	rte_smp_wmb();
+
+	page = addr / VHOST_LOG_PAGE;
+	while (page * VHOST_LOG_PAGE < addr + len) {
+		vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page);
+		page += 1;
+	}
+}
 
+static inline void __attribute__((always_inline))
+vhost_log_used_vring(struct virtio_net *dev, struct vhost_virtqueue *vq,
+		     uint64_t offset, uint64_t len)
+{
+	vhost_log_write(dev, vq->log_guest_addr + offset, len);
+}
 
 /* Macros for printing using RTE_LOG */
 #define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
@@ -231,25 +271,6 @@ extern uint64_t VHOST_FEATURES;
 #define MAX_VHOST_DEVICE	1024
 extern struct virtio_net *vhost_devices[MAX_VHOST_DEVICE];
 
-/* Convert guest physical Address to host virtual address */
-static inline uint64_t __attribute__((always_inline))
-gpa_to_vva(struct virtio_net *dev, uint64_t gpa)
-{
-	struct virtio_memory_region *reg;
-	uint32_t i;
-
-	for (i = 0; i < dev->mem->nregions; i++) {
-		reg = &dev->mem->regions[i];
-		if (gpa >= reg->guest_phys_addr &&
-		    gpa <  reg->guest_phys_addr + reg->size) {
-			return gpa - reg->guest_phys_addr +
-			       reg->host_user_addr;
-		}
-	}
-
-	return 0;
-}
-
 /* Convert guest physical address to host physical address */
 static inline phys_addr_t __attribute__((always_inline))
 gpa_to_hpa(struct virtio_net *dev, uint64_t gpa, uint64_t size)
@@ -270,7 +291,6 @@ gpa_to_hpa(struct virtio_net *dev, uint64_t gpa, uint64_t size)
 	return 0;
 }
 
-struct virtio_net_device_ops const *notify_ops;
 struct virtio_net *get_device(int vid);
 
 int vhost_new_device(void);
@@ -278,11 +298,13 @@ void cleanup_device(struct virtio_net *dev, int destroy);
 void reset_device(struct virtio_net *dev);
 void vhost_destroy_device(int);
 
-int alloc_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx);
+int alloc_vring_queue(struct virtio_net *dev, uint32_t vring_idx);
 
 void vhost_set_ifname(int, const char *if_name, unsigned int if_len);
 void vhost_enable_dequeue_zero_copy(int vid);
 
+struct vhost_device_ops const *vhost_driver_callback_get(const char *path);
+
 /*
  * Backend-specific cleanup.
  *
diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 0cb1c677..5c8058b6 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -51,6 +51,9 @@
 #include "vhost.h"
 #include "vhost_user.h"
 
+#define VIRTIO_MIN_MTU 68
+#define VIRTIO_MAX_MTU 65535
+
 static const char *vhost_message_str[VHOST_USER_MAX] = {
 	[VHOST_USER_NONE] = "VHOST_USER_NONE",
 	[VHOST_USER_GET_FEATURES] = "VHOST_USER_GET_FEATURES",
@@ -72,6 +75,7 @@ static const char *vhost_message_str[VHOST_USER_MAX] = {
 	[VHOST_USER_GET_QUEUE_NUM]  = "VHOST_USER_GET_QUEUE_NUM",
 	[VHOST_USER_SET_VRING_ENABLE]  = "VHOST_USER_SET_VRING_ENABLE",
 	[VHOST_USER_SEND_RARP]  = "VHOST_USER_SEND_RARP",
+	[VHOST_USER_NET_SET_MTU]  = "VHOST_USER_NET_SET_MTU",
 };
 
 static uint64_t
@@ -88,7 +92,7 @@ static void
 free_mem_region(struct virtio_net *dev)
 {
 	uint32_t i;
-	struct virtio_memory_region *reg;
+	struct rte_vhost_mem_region *reg;
 
 	if (!dev || !dev->mem)
 		return;
@@ -131,7 +135,7 @@ vhost_user_reset_owner(struct virtio_net *dev)
 {
 	if (dev->flags & VIRTIO_DEV_RUNNING) {
 		dev->flags &= ~VIRTIO_DEV_RUNNING;
-		notify_ops->destroy_device(dev->vid);
+		dev->notify_ops->destroy_device(dev->vid);
 	}
 
 	cleanup_device(dev, 0);
@@ -143,9 +147,12 @@ vhost_user_reset_owner(struct virtio_net *dev)
  * The features that we support are requested.
  */
 static uint64_t
-vhost_user_get_features(void)
+vhost_user_get_features(struct virtio_net *dev)
 {
-	return VHOST_FEATURES;
+	uint64_t features = 0;
+
+	rte_vhost_driver_get_features(dev->ifname, &features);
+	return features;
 }
 
 /*
@@ -154,9 +161,17 @@ vhost_user_get_features(void)
 static int
 vhost_user_set_features(struct virtio_net *dev, uint64_t features)
 {
-	if (features & ~VHOST_FEATURES)
+	uint64_t vhost_features = 0;
+
+	rte_vhost_driver_get_features(dev->ifname, &vhost_features);
+	if (features & ~vhost_features)
 		return -1;
 
+	if ((dev->flags & VIRTIO_DEV_RUNNING) && dev->features != features) {
+		if (dev->notify_ops->features_changed)
+			dev->notify_ops->features_changed(dev->vid, features);
+	}
+
 	dev->features = features;
 	if (dev->features &
 		((1 << VIRTIO_NET_F_MRG_RXBUF) | (1ULL << VIRTIO_F_VERSION_1))) {
@@ -223,12 +238,7 @@ numa_realloc(struct virtio_net *dev, int index)
 	struct vhost_virtqueue *old_vq, *vq;
 	int ret;
 
-	/*
-	 * vq is allocated on pairs, we should try to do realloc
-	 * on first queue of one queue pair only.
-	 */
-	if (index % VIRTIO_QNUM != 0)
-		return dev;
+	enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
 
 	old_dev = dev;
 	vq = old_vq = dev->virtqueue[index];
@@ -247,8 +257,7 @@ numa_realloc(struct virtio_net *dev, int index)
 	if (oldnode != newnode) {
 		RTE_LOG(INFO, VHOST_CONFIG,
 			"reallocate vq from %d to %d node\n", oldnode, newnode);
-		vq = rte_malloc_socket(NULL, sizeof(*vq) * VIRTIO_QNUM, 0,
-				       newnode);
+		vq = rte_malloc_socket(NULL, sizeof(*vq), 0, newnode);
 		if (!vq)
 			return dev;
 
@@ -280,7 +289,6 @@ numa_realloc(struct virtio_net *dev, int index)
 
 out:
 	dev->virtqueue[index] = vq;
-	dev->virtqueue[index + 1] = vq + 1;
 	vhost_devices[dev->vid] = dev;
 
 	return dev;
@@ -300,7 +308,7 @@ numa_realloc(struct virtio_net *dev, int index __rte_unused)
 static uint64_t
 qva_to_vva(struct virtio_net *dev, uint64_t qva)
 {
-	struct virtio_memory_region *reg;
+	struct rte_vhost_mem_region *reg;
 	uint32_t i;
 
 	/* Find the region where the address lives. */
@@ -428,7 +436,7 @@ add_one_guest_page(struct virtio_net *dev, uint64_t guest_phys_addr,
 }
 
 static void
-add_guest_pages(struct virtio_net *dev, struct virtio_memory_region *reg,
+add_guest_pages(struct virtio_net *dev, struct rte_vhost_mem_region *reg,
 		uint64_t page_size)
 {
 	uint64_t reg_size = reg->size;
@@ -488,7 +496,7 @@ static int
 vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 {
 	struct VhostUserMemory memory = pmsg->payload.memory;
-	struct virtio_memory_region *reg;
+	struct rte_vhost_mem_region *reg;
 	void *mmap_addr;
 	uint64_t mmap_size;
 	uint64_t mmap_offset;
@@ -496,12 +504,6 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 	uint32_t i;
 	int fd;
 
-	/* Remove from the data plane. */
-	if (dev->flags & VIRTIO_DEV_RUNNING) {
-		dev->flags &= ~VIRTIO_DEV_RUNNING;
-		notify_ops->destroy_device(dev->vid);
-	}
-
 	if (dev->mem) {
 		free_mem_region(dev);
 		rte_free(dev->mem);
@@ -515,8 +517,8 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 						sizeof(struct guest_page));
 	}
 
-	dev->mem = rte_zmalloc("vhost-mem-table", sizeof(struct virtio_memory) +
-		sizeof(struct virtio_memory_region) * memory.nregions, 0);
+	dev->mem = rte_zmalloc("vhost-mem-table", sizeof(struct rte_vhost_memory) +
+		sizeof(struct rte_vhost_mem_region) * memory.nregions, 0);
 	if (dev->mem == NULL) {
 		RTE_LOG(ERR, VHOST_CONFIG,
 			"(%d) failed to allocate memory for dev->mem\n",
@@ -611,18 +613,17 @@ vq_is_ready(struct vhost_virtqueue *vq)
 static int
 virtio_is_ready(struct virtio_net *dev)
 {
-	struct vhost_virtqueue *rvq, *tvq;
+	struct vhost_virtqueue *vq;
 	uint32_t i;
 
-	for (i = 0; i < dev->virt_qp_nb; i++) {
-		rvq = dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_RXQ];
-		tvq = dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_TXQ];
+	if (dev->nr_vring == 0)
+		return 0;
 
-		if (!vq_is_ready(rvq) || !vq_is_ready(tvq)) {
-			RTE_LOG(INFO, VHOST_CONFIG,
-				"virtio is not ready for processing.\n");
+	for (i = 0; i < dev->nr_vring; i++) {
+		vq = dev->virtqueue[i];
+
+		if (!vq_is_ready(vq))
 			return 0;
-		}
 	}
 
 	RTE_LOG(INFO, VHOST_CONFIG,
@@ -635,7 +636,6 @@ vhost_user_set_vring_call(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 {
 	struct vhost_vring_file file;
 	struct vhost_virtqueue *vq;
-	uint32_t cur_qp_idx;
 
 	file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
 	if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
@@ -645,29 +645,13 @@ vhost_user_set_vring_call(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 	RTE_LOG(INFO, VHOST_CONFIG,
 		"vring call idx:%d file:%d\n", file.index, file.fd);
 
-	/*
-	 * FIXME: VHOST_SET_VRING_CALL is the first per-vring message
-	 * we get, so we do vring queue pair allocation here.
-	 */
-	cur_qp_idx = file.index / VIRTIO_QNUM;
-	if (cur_qp_idx + 1 > dev->virt_qp_nb) {
-		if (alloc_vring_queue_pair(dev, cur_qp_idx) < 0)
-			return;
-	}
-
 	vq = dev->virtqueue[file.index];
-	assert(vq != NULL);
-
 	if (vq->callfd >= 0)
 		close(vq->callfd);
 
 	vq->callfd = file.fd;
 }
 
-/*
- *  In vhost-user, when we receive kick message, will test whether virtio
- *  device is ready for packet processing.
- */
 static void
 vhost_user_set_vring_kick(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 {
@@ -686,16 +670,6 @@ vhost_user_set_vring_kick(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 	if (vq->kickfd >= 0)
 		close(vq->kickfd);
 	vq->kickfd = file.fd;
-
-	if (virtio_is_ready(dev) && !(dev->flags & VIRTIO_DEV_RUNNING)) {
-		if (dev->dequeue_zero_copy) {
-			RTE_LOG(INFO, VHOST_CONFIG,
-				"dequeue zero copy is enabled\n");
-		}
-
-		if (notify_ops->new_device(dev->vid) == 0)
-			dev->flags |= VIRTIO_DEV_RUNNING;
-	}
 }
 
 static void
@@ -726,9 +700,11 @@ vhost_user_get_vring_base(struct virtio_net *dev,
 	/* We have to stop the queue (virtio) if it is running. */
 	if (dev->flags & VIRTIO_DEV_RUNNING) {
 		dev->flags &= ~VIRTIO_DEV_RUNNING;
-		notify_ops->destroy_device(dev->vid);
+		dev->notify_ops->destroy_device(dev->vid);
 	}
 
+	dev->flags &= ~VIRTIO_DEV_READY;
+
 	/* Here we are safe to get the last used index */
 	state->num = vq->last_used_idx;
 
@@ -766,8 +742,8 @@ vhost_user_set_vring_enable(struct virtio_net *dev,
 		"set queue enable: %d to qp idx: %d\n",
 		enable, state->index);
 
-	if (notify_ops->vring_state_changed)
-		notify_ops->vring_state_changed(dev->vid, state->index, enable);
+	if (dev->notify_ops->vring_state_changed)
+		dev->notify_ops->vring_state_changed(dev->vid, state->index, enable);
 
 	dev->virtqueue[state->index]->enabled = enable;
 
@@ -865,6 +841,22 @@ vhost_user_send_rarp(struct virtio_net *dev, struct VhostUserMsg *msg)
 	return 0;
 }
 
+static int
+vhost_user_net_set_mtu(struct virtio_net *dev, struct VhostUserMsg *msg)
+{
+	if (msg->payload.u64 < VIRTIO_MIN_MTU ||
+			msg->payload.u64 > VIRTIO_MAX_MTU) {
+		RTE_LOG(ERR, VHOST_CONFIG, "Invalid MTU size (%"PRIu64")\n",
+				msg->payload.u64);
+
+		return -1;
+	}
+
+	dev->mtu = msg->payload.u64;
+
+	return 0;
+}
+
 /* return bytes# of read on success or negative val on failure. */
 static int
 read_vhost_message(int sockfd, struct VhostUserMsg *msg)
@@ -904,6 +896,7 @@ send_vhost_message(int sockfd, struct VhostUserMsg *msg)
 		return 0;
 
 	msg->flags &= ~VHOST_USER_VERSION_MASK;
+	msg->flags &= ~VHOST_USER_NEED_REPLY;
 	msg->flags |= VHOST_USER_VERSION;
 	msg->flags |= VHOST_USER_REPLY_MASK;
 
@@ -913,6 +906,44 @@ send_vhost_message(int sockfd, struct VhostUserMsg *msg)
 	return ret;
 }
 
+/*
+ * Allocate a queue pair if it hasn't been allocated yet
+ */
+static int
+vhost_user_check_and_alloc_queue_pair(struct virtio_net *dev, VhostUserMsg *msg)
+{
+	uint16_t vring_idx;
+
+	switch (msg->request) {
+	case VHOST_USER_SET_VRING_KICK:
+	case VHOST_USER_SET_VRING_CALL:
+	case VHOST_USER_SET_VRING_ERR:
+		vring_idx = msg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
+		break;
+	case VHOST_USER_SET_VRING_NUM:
+	case VHOST_USER_SET_VRING_BASE:
+	case VHOST_USER_SET_VRING_ENABLE:
+		vring_idx = msg->payload.state.index;
+		break;
+	case VHOST_USER_SET_VRING_ADDR:
+		vring_idx = msg->payload.addr.index;
+		break;
+	default:
+		return 0;
+	}
+
+	if (vring_idx >= VHOST_MAX_VRING) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"invalid vring index: %u\n", vring_idx);
+		return -1;
+	}
+
+	if (dev->virtqueue[vring_idx])
+		return 0;
+
+	return alloc_vring_queue(dev, vring_idx);
+}
+
 int
 vhost_user_msg_handler(int vid, int fd)
 {
@@ -924,6 +955,16 @@ vhost_user_msg_handler(int vid, int fd)
 	if (dev == NULL)
 		return -1;
 
+	if (!dev->notify_ops) {
+		dev->notify_ops = vhost_driver_callback_get(dev->ifname);
+		if (!dev->notify_ops) {
+			RTE_LOG(ERR, VHOST_CONFIG,
+				"failed to get callback ops for driver %s\n",
+				dev->ifname);
+			return -1;
+		}
+	}
+
 	ret = read_vhost_message(fd, &msg);
 	if (ret <= 0 || msg.request >= VHOST_USER_MAX) {
 		if (ret < 0)
@@ -939,11 +980,20 @@ vhost_user_msg_handler(int vid, int fd)
 		return -1;
 	}
 
+	ret = 0;
 	RTE_LOG(INFO, VHOST_CONFIG, "read message %s\n",
 		vhost_message_str[msg.request]);
+
+	ret = vhost_user_check_and_alloc_queue_pair(dev, &msg);
+	if (ret < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"failed to alloc queue\n");
+		return -1;
+	}
+
 	switch (msg.request) {
 	case VHOST_USER_GET_FEATURES:
-		msg.payload.u64 = vhost_user_get_features();
+		msg.payload.u64 = vhost_user_get_features(dev);
 		msg.size = sizeof(msg.payload.u64);
 		send_vhost_message(fd, &msg);
 		break;
@@ -968,7 +1018,7 @@ vhost_user_msg_handler(int vid, int fd)
 		break;
 
 	case VHOST_USER_SET_MEM_TABLE:
-		vhost_user_set_mem_table(dev, &msg);
+		ret = vhost_user_set_mem_table(dev, &msg);
 		break;
 
 	case VHOST_USER_SET_LOG_BASE:
@@ -994,7 +1044,7 @@ vhost_user_msg_handler(int vid, int fd)
 		break;
 
 	case VHOST_USER_GET_VRING_BASE:
-		ret = vhost_user_get_vring_base(dev, &msg.payload.state);
+		vhost_user_get_vring_base(dev, &msg.payload.state);
 		msg.size = sizeof(msg.payload.state);
 		send_vhost_message(fd, &msg);
 		break;
@@ -1025,10 +1075,35 @@ vhost_user_msg_handler(int vid, int fd)
 		vhost_user_send_rarp(dev, &msg);
 		break;
 
+	case VHOST_USER_NET_SET_MTU:
+		ret = vhost_user_net_set_mtu(dev, &msg);
+		break;
+
 	default:
+		ret = -1;
 		break;
 
 	}
 
+	if (msg.flags & VHOST_USER_NEED_REPLY) {
+		msg.payload.u64 = !!ret;
+		msg.size = sizeof(msg.payload.u64);
+		send_vhost_message(fd, &msg);
+	}
+
+	if (!(dev->flags & VIRTIO_DEV_RUNNING) && virtio_is_ready(dev)) {
+		dev->flags |= VIRTIO_DEV_READY;
+
+		if (!(dev->flags & VIRTIO_DEV_RUNNING)) {
+			if (dev->dequeue_zero_copy) {
+				RTE_LOG(INFO, VHOST_CONFIG,
+						"dequeue zero copy is enabled\n");
+			}
+
+			if (dev->notify_ops->new_device(dev->vid) == 0)
+				dev->flags |= VIRTIO_DEV_RUNNING;
+		}
+	}
+
 	return 0;
 }
diff --git a/lib/librte_vhost/vhost_user.h b/lib/librte_vhost/vhost_user.h
index ba78d326..35ebd719 100644
--- a/lib/librte_vhost/vhost_user.h
+++ b/lib/librte_vhost/vhost_user.h
@@ -37,7 +37,7 @@
 #include <stdint.h>
 #include <linux/vhost.h>
 
-#include "rte_virtio_net.h"
+#include "rte_vhost.h"
 
 /* refer to hw/virtio/vhost-user.c */
 
@@ -46,10 +46,18 @@
 #define VHOST_USER_PROTOCOL_F_MQ	0
 #define VHOST_USER_PROTOCOL_F_LOG_SHMFD	1
 #define VHOST_USER_PROTOCOL_F_RARP	2
+#define VHOST_USER_PROTOCOL_F_REPLY_ACK	3
+#define VHOST_USER_PROTOCOL_F_NET_MTU 4
 
+/*
+ * disable REPLY_ACK feature to workaround the buggy QEMU implementation.
+ * Proved buggy QEMU includes v2.7 - v2.9.
+ */
 #define VHOST_USER_PROTOCOL_FEATURES	((1ULL << VHOST_USER_PROTOCOL_F_MQ) | \
 					 (1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD) |\
-					 (1ULL << VHOST_USER_PROTOCOL_F_RARP))
+					 (1ULL << VHOST_USER_PROTOCOL_F_RARP) | \
+					 (0ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK) | \
+					 (1ULL << VHOST_USER_PROTOCOL_F_NET_MTU))
 
 typedef enum VhostUserRequest {
 	VHOST_USER_NONE = 0,
@@ -72,6 +80,7 @@ typedef enum VhostUserRequest {
 	VHOST_USER_GET_QUEUE_NUM = 17,
 	VHOST_USER_SET_VRING_ENABLE = 18,
 	VHOST_USER_SEND_RARP = 19,
+	VHOST_USER_NET_SET_MTU = 20,
 	VHOST_USER_MAX
 } VhostUserRequest;
 
@@ -98,6 +107,7 @@ typedef struct VhostUserMsg {
 
 #define VHOST_USER_VERSION_MASK     0x3
 #define VHOST_USER_REPLY_MASK       (0x1 << 2)
+#define VHOST_USER_NEED_REPLY		(0x1 << 3)
 	uint32_t flags;
 	uint32_t size; /* the following payload size */
 	union {
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 337470d6..48219e05 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -39,7 +39,7 @@
 #include <rte_memcpy.h>
 #include <rte_ether.h>
 #include <rte_ip.h>
-#include <rte_virtio_net.h>
+#include <rte_vhost.h>
 #include <rte_tcp.h>
 #include <rte_udp.h>
 #include <rte_sctp.h>
@@ -48,47 +48,11 @@
 #include "vhost.h"
 
 #define MAX_PKT_BURST 32
-#define VHOST_LOG_PAGE	4096
-
-static inline void __attribute__((always_inline))
-vhost_log_page(uint8_t *log_base, uint64_t page)
-{
-	log_base[page / 8] |= 1 << (page % 8);
-}
-
-static inline void __attribute__((always_inline))
-vhost_log_write(struct virtio_net *dev, uint64_t addr, uint64_t len)
-{
-	uint64_t page;
-
-	if (likely(((dev->features & (1ULL << VHOST_F_LOG_ALL)) == 0) ||
-		   !dev->log_base || !len))
-		return;
-
-	if (unlikely(dev->log_size <= ((addr + len - 1) / VHOST_LOG_PAGE / 8)))
-		return;
-
-	/* To make sure guest memory updates are committed before logging */
-	rte_smp_wmb();
-
-	page = addr / VHOST_LOG_PAGE;
-	while (page * VHOST_LOG_PAGE < addr + len) {
-		vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page);
-		page += 1;
-	}
-}
-
-static inline void __attribute__((always_inline))
-vhost_log_used_vring(struct virtio_net *dev, struct vhost_virtqueue *vq,
-		     uint64_t offset, uint64_t len)
-{
-	vhost_log_write(dev, vq->log_guest_addr + offset, len);
-}
 
 static bool
-is_valid_virt_queue_idx(uint32_t idx, int is_tx, uint32_t qp_nb)
+is_valid_virt_queue_idx(uint32_t idx, int is_tx, uint32_t nr_vring)
 {
-	return (is_tx ^ (idx & 1)) == 0 && idx < qp_nb * VIRTIO_QNUM;
+	return (is_tx ^ (idx & 1)) == 0 && idx < nr_vring;
 }
 
 static inline void __attribute__((always_inline))
@@ -141,6 +105,12 @@ update_shadow_used_ring(struct vhost_virtqueue *vq,
 	vq->shadow_used_ring[i].len = len;
 }
 
+/* avoid write operation when necessary, to lessen cache issues */
+#define ASSIGN_UNLESS_EQUAL(var, val) do {	\
+	if ((var) != (val))			\
+		(var) = (val);			\
+} while (0)
+
 static void
 virtio_enqueue_offload(struct rte_mbuf *m_buf, struct virtio_net_hdr *net_hdr)
 {
@@ -162,6 +132,10 @@ virtio_enqueue_offload(struct rte_mbuf *m_buf, struct virtio_net_hdr *net_hdr)
 						cksum));
 			break;
 		}
+	} else {
+		ASSIGN_UNLESS_EQUAL(net_hdr->csum_start, 0);
+		ASSIGN_UNLESS_EQUAL(net_hdr->csum_offset, 0);
+		ASSIGN_UNLESS_EQUAL(net_hdr->flags, 0);
 	}
 
 	if (m_buf->ol_flags & PKT_TX_TCP_SEG) {
@@ -172,19 +146,13 @@ virtio_enqueue_offload(struct rte_mbuf *m_buf, struct virtio_net_hdr *net_hdr)
 		net_hdr->gso_size = m_buf->tso_segsz;
 		net_hdr->hdr_len = m_buf->l2_len + m_buf->l3_len
 					+ m_buf->l4_len;
+	} else {
+		ASSIGN_UNLESS_EQUAL(net_hdr->gso_type, 0);
+		ASSIGN_UNLESS_EQUAL(net_hdr->gso_size, 0);
+		ASSIGN_UNLESS_EQUAL(net_hdr->hdr_len, 0);
 	}
 }
 
-static inline void
-copy_virtio_net_hdr(struct virtio_net *dev, uint64_t desc_addr,
-		    struct virtio_net_hdr_mrg_rxbuf hdr)
-{
-	if (dev->vhost_hlen == sizeof(struct virtio_net_hdr_mrg_rxbuf))
-		*(struct virtio_net_hdr_mrg_rxbuf *)(uintptr_t)desc_addr = hdr;
-	else
-		*(struct virtio_net_hdr *)(uintptr_t)desc_addr = hdr.hdr;
-}
-
 static inline int __attribute__((always_inline))
 copy_mbuf_to_desc(struct virtio_net *dev, struct vring_desc *descs,
 		  struct rte_mbuf *m, uint16_t desc_idx, uint32_t size)
@@ -194,12 +162,11 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct vring_desc *descs,
 	uint32_t cpy_len;
 	struct vring_desc *desc;
 	uint64_t desc_addr;
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0};
 	/* A counter to avoid desc dead loop chain */
 	uint16_t nr_desc = 1;
 
 	desc = &descs[desc_idx];
-	desc_addr = gpa_to_vva(dev, desc->addr);
+	desc_addr = rte_vhost_gpa_to_vva(dev->mem, desc->addr);
 	/*
 	 * Checking of 'desc_addr' placed outside of 'unlikely' macro to avoid
 	 * performance issue with some versions of gcc (4.8.4 and 5.3.0) which
@@ -210,8 +177,7 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct vring_desc *descs,
 
 	rte_prefetch0((void *)(uintptr_t)desc_addr);
 
-	virtio_enqueue_offload(m, &virtio_hdr.hdr);
-	copy_virtio_net_hdr(dev, desc_addr, virtio_hdr);
+	virtio_enqueue_offload(m, (struct virtio_net_hdr *)(uintptr_t)desc_addr);
 	vhost_log_write(dev, desc->addr, dev->vhost_hlen);
 	PRINT_PACKET(dev, (uintptr_t)desc_addr, dev->vhost_hlen, 0);
 
@@ -239,7 +205,7 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct vring_desc *descs,
 				return -1;
 
 			desc = &descs[desc->next];
-			desc_addr = gpa_to_vva(dev, desc->addr);
+			desc_addr = rte_vhost_gpa_to_vva(dev->mem, desc->addr);
 			if (unlikely(!desc_addr))
 				return -1;
 
@@ -283,7 +249,7 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
 	uint32_t i, sz;
 
 	LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__);
-	if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->virt_qp_nb))) {
+	if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->nr_vring))) {
 		RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n",
 			dev->vid, __func__, queue_id);
 		return 0;
@@ -323,7 +289,8 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
 		int err;
 
 		if (vq->desc[desc_idx].flags & VRING_DESC_F_INDIRECT) {
-			descs = (struct vring_desc *)(uintptr_t)gpa_to_vva(dev,
+			descs = (struct vring_desc *)(uintptr_t)
+				rte_vhost_gpa_to_vva(dev->mem,
 					vq->desc[desc_idx].addr);
 			if (unlikely(!descs)) {
 				count = i;
@@ -383,7 +350,7 @@ fill_vec_buf(struct virtio_net *dev, struct vhost_virtqueue *vq,
 
 	if (vq->desc[idx].flags & VRING_DESC_F_INDIRECT) {
 		descs = (struct vring_desc *)(uintptr_t)
-					gpa_to_vva(dev, vq->desc[idx].addr);
+			rte_vhost_gpa_to_vva(dev->mem, vq->desc[idx].addr);
 		if (unlikely(!descs))
 			return -1;
 
@@ -461,7 +428,6 @@ static inline int __attribute__((always_inline))
 copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct rte_mbuf *m,
 			    struct buf_vector *buf_vec, uint16_t num_buffers)
 {
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0};
 	uint32_t vec_idx = 0;
 	uint64_t desc_addr;
 	uint32_t mbuf_offset, mbuf_avail;
@@ -473,7 +439,7 @@ copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct rte_mbuf *m,
 	if (unlikely(m == NULL))
 		return -1;
 
-	desc_addr = gpa_to_vva(dev, buf_vec[vec_idx].buf_addr);
+	desc_addr = rte_vhost_gpa_to_vva(dev->mem, buf_vec[vec_idx].buf_addr);
 	if (buf_vec[vec_idx].buf_len < dev->vhost_hlen || !desc_addr)
 		return -1;
 
@@ -482,7 +448,6 @@ copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct rte_mbuf *m,
 	hdr_phys_addr = buf_vec[vec_idx].buf_addr;
 	rte_prefetch0((void *)(uintptr_t)hdr_addr);
 
-	virtio_hdr.num_buffers = num_buffers;
 	LOG_DEBUG(VHOST_DATA, "(%d) RX: num merge buffers %d\n",
 		dev->vid, num_buffers);
 
@@ -495,7 +460,8 @@ copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct rte_mbuf *m,
 		/* done with current desc buf, get the next one */
 		if (desc_avail == 0) {
 			vec_idx++;
-			desc_addr = gpa_to_vva(dev, buf_vec[vec_idx].buf_addr);
+			desc_addr = rte_vhost_gpa_to_vva(dev->mem,
+					buf_vec[vec_idx].buf_addr);
 			if (unlikely(!desc_addr))
 				return -1;
 
@@ -514,8 +480,13 @@ copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct rte_mbuf *m,
 		}
 
 		if (hdr_addr) {
-			virtio_enqueue_offload(hdr_mbuf, &virtio_hdr.hdr);
-			copy_virtio_net_hdr(dev, hdr_addr, virtio_hdr);
+			struct virtio_net_hdr_mrg_rxbuf *hdr;
+
+			hdr = (struct virtio_net_hdr_mrg_rxbuf *)(uintptr_t)
+				hdr_addr;
+			virtio_enqueue_offload(hdr_mbuf, &hdr->hdr);
+			ASSIGN_UNLESS_EQUAL(hdr->num_buffers, num_buffers);
+
 			vhost_log_write(dev, hdr_phys_addr, dev->vhost_hlen);
 			PRINT_PACKET(dev, (uintptr_t)hdr_addr,
 				     dev->vhost_hlen, 0);
@@ -552,7 +523,7 @@ virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id,
 	uint16_t avail_head;
 
 	LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__);
-	if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->virt_qp_nb))) {
+	if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->nr_vring))) {
 		RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n",
 			dev->vid, __func__, queue_id);
 		return 0;
@@ -663,14 +634,14 @@ parse_ethernet(struct rte_mbuf *m, uint16_t *l4_proto, void **l4_hdr)
 
 	switch (ethertype) {
 	case ETHER_TYPE_IPv4:
-		ipv4_hdr = (struct ipv4_hdr *)l3_hdr;
+		ipv4_hdr = l3_hdr;
 		*l4_proto = ipv4_hdr->next_proto_id;
 		m->l3_len = (ipv4_hdr->version_ihl & 0x0f) * 4;
 		*l4_hdr = (char *)l3_hdr + m->l3_len;
 		m->ol_flags |= PKT_TX_IPV4;
 		break;
 	case ETHER_TYPE_IPv6:
-		ipv6_hdr = (struct ipv6_hdr *)l3_hdr;
+		ipv6_hdr = l3_hdr;
 		*l4_proto = ipv6_hdr->proto;
 		m->l3_len = sizeof(struct ipv6_hdr);
 		*l4_hdr = (char *)l3_hdr + m->l3_len;
@@ -720,7 +691,7 @@ vhost_dequeue_offload(struct virtio_net_hdr *hdr, struct rte_mbuf *m)
 		switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 		case VIRTIO_NET_HDR_GSO_TCPV4:
 		case VIRTIO_NET_HDR_GSO_TCPV6:
-			tcp_hdr = (struct tcp_hdr *)l4_hdr;
+			tcp_hdr = l4_hdr;
 			m->ol_flags |= PKT_TX_TCP_SEG;
 			m->tso_segsz = hdr->gso_size;
 			m->l4_len = (tcp_hdr->data_off & 0xf0) >> 2;
@@ -798,7 +769,7 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vring_desc *descs,
 			(desc->flags & VRING_DESC_F_INDIRECT))
 		return -1;
 
-	desc_addr = gpa_to_vva(dev, desc->addr);
+	desc_addr = rte_vhost_gpa_to_vva(dev->mem, desc->addr);
 	if (unlikely(!desc_addr))
 		return -1;
 
@@ -818,7 +789,7 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vring_desc *descs,
 		if (unlikely(desc->flags & VRING_DESC_F_INDIRECT))
 			return -1;
 
-		desc_addr = gpa_to_vva(dev, desc->addr);
+		desc_addr = rte_vhost_gpa_to_vva(dev->mem, desc->addr);
 		if (unlikely(!desc_addr))
 			return -1;
 
@@ -882,7 +853,7 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vring_desc *descs,
 			if (unlikely(desc->flags & VRING_DESC_F_INDIRECT))
 				return -1;
 
-			desc_addr = gpa_to_vva(dev, desc->addr);
+			desc_addr = rte_vhost_gpa_to_vva(dev->mem, desc->addr);
 			if (unlikely(!desc_addr))
 				return -1;
 
@@ -905,6 +876,8 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vring_desc *descs,
 					"allocate memory for mbuf.\n");
 				return -1;
 			}
+			if (unlikely(dev->dequeue_zero_copy))
+				rte_mbuf_refcnt_update(cur, 1);
 
 			prev->next = cur;
 			prev->data_len = mbuf_offset;
@@ -1017,7 +990,7 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
 	if (!dev)
 		return 0;
 
-	if (unlikely(!is_valid_virt_queue_idx(queue_id, 1, dev->virt_qp_nb))) {
+	if (unlikely(!is_valid_virt_queue_idx(queue_id, 1, dev->nr_vring))) {
 		RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n",
 			dev->vid, __func__, queue_id);
 		return 0;
@@ -1056,9 +1029,21 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
 	 * array, to looks like that guest actually send such packet.
 	 *
 	 * Check user_send_rarp() for more information.
+	 *
+	 * broadcast_rarp shares a cacheline in the virtio_net structure
+	 * with some fields that are accessed during enqueue and
+	 * rte_atomic16_cmpset() causes a write if using cmpxchg. This could
+	 * result in false sharing between enqueue and dequeue.
+	 *
+	 * Prevent unnecessary false sharing by reading broadcast_rarp first
+	 * and only performing cmpset if the read indicates it is likely to
+	 * be set.
 	 */
-	if (unlikely(rte_atomic16_cmpset((volatile uint16_t *)
-					 &dev->broadcast_rarp.cnt, 1, 0))) {
+
+	if (unlikely(rte_atomic16_read(&dev->broadcast_rarp) &&
+			rte_atomic16_cmpset((volatile uint16_t *)
+				&dev->broadcast_rarp.cnt, 1, 0))) {
+
 		rarp_mbuf = rte_pktmbuf_alloc(mbuf_pool);
 		if (rarp_mbuf == NULL) {
 			RTE_LOG(ERR, VHOST_DATA,
@@ -1113,7 +1098,8 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
 			rte_prefetch0(&vq->desc[desc_indexes[i + 1]]);
 
 		if (vq->desc[desc_indexes[i]].flags & VRING_DESC_F_INDIRECT) {
-			desc = (struct vring_desc *)(uintptr_t)gpa_to_vva(dev,
+			desc = (struct vring_desc *)(uintptr_t)
+				rte_vhost_gpa_to_vva(dev->mem,
 					vq->desc[desc_indexes[i]].addr);
 			if (unlikely(!desc))
 				break;