vhost: convert vhost device driver to a plugin

convert vhost device driver to a plugin as described in
https://jira.fd.io/browse/VPP-2065

Type: improvement

Signed-off-by: Steven Luong <sluong@cisco.com>
Change-Id: Ibfe2f351bcaed36a04b136d082ae414145dd37b5

1 files changed, 2613 insertions, 0 deletions

diff --git a/src/plugins/vhost/vhost_user.c b/src/plugins/vhost/vhost_user.c
new file mode 100644
index 00000000000..fac20800848
--- /dev/null
+++ b/src/plugins/vhost/vhost_user.c
@@ -0,0 +1,2613 @@
+/*
+ *------------------------------------------------------------------
+ * vhost.c - vhost-user
+ *
+ * Copyright (c) 2014-2018 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *------------------------------------------------------------------
+ */
+
+#include <fcntl.h>		/* for open */
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/uio.h>		/* for iovec */
+#include <netinet/in.h>
+#include <sys/vfs.h>
+
+#include <linux/if_arp.h>
+#include <linux/if_tun.h>
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/devices/devices.h>
+#include <vnet/feature/feature.h>
+#include <vnet/interface/rx_queue_funcs.h>
+#include <vnet/interface/tx_queue_funcs.h>
+
+#include <vhost/vhost_user.h>
+#include <vhost/vhost_user_inline.h>
+
+/**
+ * @file
+ * @brief vHost User Device Driver.
+ *
+ * This file contains the source code for vHost User interface.
+ */
+
+
+vlib_node_registration_t vhost_user_send_interrupt_node;
+
+/* *INDENT-OFF* */
+vhost_user_main_t vhost_user_main = {
+  .mtu_bytes = 1518,
+};
+
+VNET_HW_INTERFACE_CLASS (vhost_interface_class, static) = {
+  .name = "vhost-user",
+};
+/* *INDENT-ON* */
+
+static long
+get_huge_page_size (int fd)
+{
+  struct statfs s;
+  fstatfs (fd, &s);
+  return s.f_bsize;
+}
+
+static void
+unmap_all_mem_regions (vhost_user_intf_t * vui)
+{
+  int i, r, q;
+  vhost_user_vring_t *vq;
+
+  for (i = 0; i < vui->nregions; i++)
+    {
+      if (vui->region_mmap_addr[i] != MAP_FAILED)
+	{
+
+	  long page_sz = get_huge_page_size (vui->region_mmap_fd[i]);
+
+	  ssize_t map_sz = (vui->regions[i].memory_size +
+			    vui->regions[i].mmap_offset +
+			    page_sz - 1) & ~(page_sz - 1);
+
+	  r =
+	    munmap (vui->region_mmap_addr[i] - vui->regions[i].mmap_offset,
+		    map_sz);
+
+	  vu_log_debug (vui, "unmap memory region %d addr 0x%lx len 0x%lx "
+			"page_sz 0x%x", i, vui->region_mmap_addr[i], map_sz,
+			page_sz);
+
+	  vui->region_mmap_addr[i] = MAP_FAILED;
+
+	  if (r == -1)
+	    {
+	      vu_log_err (vui, "failed to unmap memory region (errno %d)",
+			  errno);
+	    }
+	  close (vui->region_mmap_fd[i]);
+	}
+    }
+  vui->nregions = 0;
+
+  FOR_ALL_VHOST_RX_TXQ (q, vui)
+  {
+    vq = &vui->vrings[q];
+    vq->avail = 0;
+    vq->used = 0;
+    vq->desc = 0;
+  }
+}
+
+static_always_inline void
+vhost_user_tx_thread_placement (vhost_user_intf_t *vui, u32 qid)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  vhost_user_vring_t *rxvq = &vui->vrings[qid];
+  u32 q = qid >> 1, rxvq_count;
+
+  ASSERT ((qid & 1) == 0);
+  if (!rxvq->started || !rxvq->enabled)
+    return;
+
+  rxvq_count = (qid >> 1) + 1;
+  if (rxvq->queue_index == ~0)
+    {
+      rxvq->queue_index =
+	vnet_hw_if_register_tx_queue (vnm, vui->hw_if_index, q);
+      rxvq->qid = q;
+    }
+
+  FOR_ALL_VHOST_RXQ (q, vui)
+  {
+    vhost_user_vring_t *rxvq = &vui->vrings[q];
+    u32 qi = rxvq->queue_index;
+
+    if (rxvq->queue_index == ~0)
+      break;
+    for (u32 i = 0; i < vlib_get_n_threads (); i++)
+      vnet_hw_if_tx_queue_unassign_thread (vnm, qi, i);
+  }
+
+  for (u32 i = 0; i < vlib_get_n_threads (); i++)
+    {
+      vhost_user_vring_t *rxvq =
+	&vui->vrings[VHOST_VRING_IDX_RX (i % rxvq_count)];
+      u32 qi = rxvq->queue_index;
+
+      vnet_hw_if_tx_queue_assign_thread (vnm, qi, i);
+    }
+
+  vnet_hw_if_update_runtime_data (vnm, vui->hw_if_index);
+}
+
+/**
+ * @brief Unassign existing interface/queue to thread mappings and re-assign
+ * new interface/queue to thread mappings
+ */
+static_always_inline void
+vhost_user_rx_thread_placement (vhost_user_intf_t * vui, u32 qid)
+{
+  vhost_user_vring_t *txvq = &vui->vrings[qid];
+  vnet_main_t *vnm = vnet_get_main ();
+  int rv;
+  u32 q = qid >> 1;
+  vhost_user_main_t *vum = &vhost_user_main;
+
+  ASSERT ((qid & 1) == 1);	// should be odd
+  // Assign new queue mappings for the interface
+  if (txvq->queue_index != ~0)
+    return;
+  vnet_hw_if_set_input_node (vnm, vui->hw_if_index,
+			     vhost_user_input_node.index);
+  txvq->queue_index = vnet_hw_if_register_rx_queue (vnm, vui->hw_if_index, q,
+						    VNET_HW_IF_RXQ_THREAD_ANY);
+  txvq->thread_index =
+    vnet_hw_if_get_rx_queue_thread_index (vnm, txvq->queue_index);
+
+  if (txvq->mode == VNET_HW_IF_RX_MODE_UNKNOWN)
+    /* Set polling as the default */
+    txvq->mode = VNET_HW_IF_RX_MODE_POLLING;
+  if (txvq->mode == VNET_HW_IF_RX_MODE_POLLING)
+    {
+      vhost_cpu_t *cpu = vec_elt_at_index (vum->cpus, txvq->thread_index);
+      /* Keep a polling queue count for each thread */
+      cpu->polling_q_count++;
+    }
+  txvq->qid = q;
+  rv = vnet_hw_if_set_rx_queue_mode (vnm, txvq->queue_index, txvq->mode);
+  if (rv)
+    vu_log_warn (vui, "unable to set rx mode for interface %d, "
+		 "queue %d: rc=%d", vui->hw_if_index, q, rv);
+  vnet_hw_if_update_runtime_data (vnm, vui->hw_if_index);
+}
+
+/** @brief Returns whether at least one TX and one RX vring are enabled */
+static_always_inline int
+vhost_user_intf_ready (vhost_user_intf_t * vui)
+{
+  int i, found[2] = { };	//RX + TX
+
+  for (i = 0; i < vui->num_qid; i++)
+    if (vui->vrings[i].started && vui->vrings[i].enabled)
+      found[i & 1] = 1;
+
+  return found[0] && found[1];
+}
+
+static_always_inline void
+vhost_user_update_iface_state (vhost_user_intf_t * vui)
+{
+  /* if we have pointers to descriptor table, go up */
+  int is_ready = vhost_user_intf_ready (vui);
+  if (is_ready != vui->is_ready)
+    {
+      vu_log_debug (vui, "interface %d %s", vui->sw_if_index,
+		    is_ready ? "ready" : "down");
+      if (vui->admin_up)
+	vnet_hw_interface_set_flags (vnet_get_main (), vui->hw_if_index,
+				     is_ready ? VNET_HW_INTERFACE_FLAG_LINK_UP
+				     : 0);
+      vui->is_ready = is_ready;
+    }
+}
+
+static clib_error_t *
+vhost_user_callfd_read_ready (clib_file_t * uf)
+{
+  __attribute__ ((unused)) int n;
+  u8 buff[8];
+
+  n = read (uf->file_descriptor, ((char *) &buff), 8);
+
+  return 0;
+}
+
+static_always_inline void
+vhost_user_thread_placement (vhost_user_intf_t * vui, u32 qid)
+{
+  if (qid & 1)			// RX is odd, TX is even
+    {
+      if (vui->vrings[qid].queue_index == ~0)
+	vhost_user_rx_thread_placement (vui, qid);
+    }
+  else
+    vhost_user_tx_thread_placement (vui, qid);
+}
+
+static clib_error_t *
+vhost_user_kickfd_read_ready (clib_file_t * uf)
+{
+  __attribute__ ((unused)) ssize_t n;
+  u8 buff[8];
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui =
+    pool_elt_at_index (vum->vhost_user_interfaces, uf->private_data >> 8);
+  u32 qid = uf->private_data & 0xff;
+  u32 is_txq = qid & 1;
+  vhost_user_vring_t *vq = &vui->vrings[qid];
+  vnet_main_t *vnm = vnet_get_main ();
+
+  n = read (uf->file_descriptor, buff, 8);
+  if (vq->started == 0)
+    {
+      vq->started = 1;
+      vhost_user_thread_placement (vui, qid);
+      vhost_user_update_iface_state (vui);
+      if (is_txq)
+	vnet_hw_if_set_rx_queue_file_index (vnm, vq->queue_index,
+					    vq->kickfd_idx);
+    }
+
+  if (is_txq && (vq->mode != VNET_HW_IF_RX_MODE_POLLING) &&
+      vhost_user_intf_ready (vui))
+    {
+      vhost_cpu_t *cpu = vec_elt_at_index (vum->cpus, vq->thread_index);
+      /*
+       * If the thread has more than 1 queue and the other queue is in polling
+       * mode, there is no need to trigger an interrupt
+       */
+      if (cpu->polling_q_count == 0)
+	vnet_hw_if_rx_queue_set_int_pending (vnm, vq->queue_index);
+    }
+
+  return 0;
+}
+
+static_always_inline void
+vhost_user_vring_init (vhost_user_intf_t * vui, u32 qid)
+{
+  vhost_user_vring_t *vring = &vui->vrings[qid];
+
+  clib_memset (vring, 0, sizeof (*vring));
+  vring->kickfd_idx = ~0;
+  vring->callfd_idx = ~0;
+  vring->errfd = -1;
+  vring->qid = -1;
+  vring->queue_index = ~0;
+  vring->thread_index = ~0;
+  vring->mode = VNET_HW_IF_RX_MODE_POLLING;
+
+  clib_spinlock_init (&vring->vring_lock);
+
+  /*
+   * We have a bug with some qemu 2.5, and this may be a fix.
+   * Feel like interpretation holy text, but this is from vhost-user.txt.
+   * "
+   * One queue pair is enabled initially. More queues are enabled
+   * dynamically, by sending message VHOST_USER_SET_VRING_ENABLE.
+   * "
+   * Don't know who's right, but this is what DPDK does.
+   */
+  if (qid == 0 || qid == 1)
+    vring->enabled = 1;
+}
+
+static_always_inline void
+vhost_user_vring_close (vhost_user_intf_t * vui, u32 qid)
+{
+  vhost_user_vring_t *vring = &vui->vrings[qid];
+
+  if (vring->kickfd_idx != ~0)
+    {
+      clib_file_t *uf = pool_elt_at_index (file_main.file_pool,
+					   vring->kickfd_idx);
+      clib_file_del (&file_main, uf);
+      vring->kickfd_idx = ~0;
+    }
+  if (vring->callfd_idx != ~0)
+    {
+      clib_file_t *uf = pool_elt_at_index (file_main.file_pool,
+					   vring->callfd_idx);
+      clib_file_del (&file_main, uf);
+      vring->callfd_idx = ~0;
+    }
+  if (vring->errfd != -1)
+    {
+      close (vring->errfd);
+      vring->errfd = -1;
+    }
+
+  clib_spinlock_free (&vring->vring_lock);
+
+  // save the needed information in vrings prior to being wiped out
+  u16 q = vui->vrings[qid].qid;
+  u32 queue_index = vui->vrings[qid].queue_index;
+  u32 mode = vui->vrings[qid].mode;
+  u32 thread_index = vui->vrings[qid].thread_index;
+  vhost_user_vring_init (vui, qid);
+  vui->vrings[qid].qid = q;
+  vui->vrings[qid].queue_index = queue_index;
+  vui->vrings[qid].mode = mode;
+  vui->vrings[qid].thread_index = thread_index;
+}
+
+static_always_inline void
+vhost_user_if_disconnect (vhost_user_intf_t * vui)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  int q;
+
+  vnet_hw_interface_set_flags (vnm, vui->hw_if_index, 0);
+
+  if (vui->clib_file_index != ~0)
+    {
+      clib_file_del (&file_main, file_main.file_pool + vui->clib_file_index);
+      vui->clib_file_index = ~0;
+    }
+
+  vui->is_ready = 0;
+
+  FOR_ALL_VHOST_RX_TXQ (q, vui) { vhost_user_vring_close (vui, q); }
+
+  unmap_all_mem_regions (vui);
+  vu_log_debug (vui, "interface ifindex %d disconnected", vui->sw_if_index);
+}
+
+void
+vhost_user_set_operation_mode (vhost_user_intf_t *vui,
+			       vhost_user_vring_t *txvq)
+{
+  if (vhost_user_is_packed_ring_supported (vui))
+    {
+      if (txvq->used_event)
+	{
+	  if (txvq->mode == VNET_HW_IF_RX_MODE_POLLING)
+	    txvq->used_event->flags = VRING_EVENT_F_DISABLE;
+	  else
+	    txvq->used_event->flags = 0;
+	}
+    }
+  else
+    {
+      if (txvq->used)
+	{
+	  if (txvq->mode == VNET_HW_IF_RX_MODE_POLLING)
+	    txvq->used->flags = VRING_USED_F_NO_NOTIFY;
+	  else
+	    txvq->used->flags = 0;
+	}
+    }
+}
+
+static clib_error_t *
+vhost_user_socket_read (clib_file_t * uf)
+{
+  int n, i, j;
+  int fd, number_of_fds = 0;
+  int fds[VHOST_MEMORY_MAX_NREGIONS];
+  vhost_user_msg_t msg;
+  struct msghdr mh;
+  struct iovec iov[1];
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui;
+  struct cmsghdr *cmsg;
+  u8 q;
+  clib_file_t template = { 0 };
+  vnet_main_t *vnm = vnet_get_main ();
+  vlib_main_t *vm = vlib_get_main ();
+
+  vui = pool_elt_at_index (vum->vhost_user_interfaces, uf->private_data);
+
+  char control[CMSG_SPACE (VHOST_MEMORY_MAX_NREGIONS * sizeof (int))];
+
+  clib_memset (&mh, 0, sizeof (mh));
+  clib_memset (control, 0, sizeof (control));
+
+  for (i = 0; i < VHOST_MEMORY_MAX_NREGIONS; i++)
+    fds[i] = -1;
+
+  /* set the payload */
+  iov[0].iov_base = (void *) &msg;
+  iov[0].iov_len = VHOST_USER_MSG_HDR_SZ;
+
+  mh.msg_iov = iov;
+  mh.msg_iovlen = 1;
+  mh.msg_control = control;
+  mh.msg_controllen = sizeof (control);
+
+  n = recvmsg (uf->file_descriptor, &mh, 0);
+
+  if (n != VHOST_USER_MSG_HDR_SZ)
+    {
+      if (n == -1)
+	{
+	  vu_log_debug (vui, "recvmsg returned error %d %s", errno,
+			strerror (errno));
+	}
+      else
+	{
+	  vu_log_debug (vui, "n (%d) != VHOST_USER_MSG_HDR_SZ (%d)",
+			n, VHOST_USER_MSG_HDR_SZ);
+	}
+      goto close_socket;
+    }
+
+  if (mh.msg_flags & MSG_CTRUNC)
+    {
+      vu_log_debug (vui, "MSG_CTRUNC is set");
+      goto close_socket;
+    }
+
+  cmsg = CMSG_FIRSTHDR (&mh);
+
+  if (cmsg && (cmsg->cmsg_len > 0) && (cmsg->cmsg_level == SOL_SOCKET) &&
+      (cmsg->cmsg_type == SCM_RIGHTS) &&
+      (cmsg->cmsg_len - CMSG_LEN (0) <=
+       VHOST_MEMORY_MAX_NREGIONS * sizeof (int)))
+    {
+      number_of_fds = (cmsg->cmsg_len - CMSG_LEN (0)) / sizeof (int);
+      clib_memcpy_fast (fds, CMSG_DATA (cmsg), number_of_fds * sizeof (int));
+    }
+
+  /* version 1, no reply bit set */
+  if ((msg.flags & 7) != 1)
+    {
+      vu_log_debug (vui, "malformed message received. closing socket");
+      goto close_socket;
+    }
+
+  {
+    int rv;
+    rv =
+      read (uf->file_descriptor, ((char *) &msg) + VHOST_USER_MSG_HDR_SZ,
+	    msg.size);
+    if (rv < 0)
+      {
+	vu_log_debug (vui, "read failed %s", strerror (errno));
+	goto close_socket;
+      }
+    else if (rv != msg.size)
+      {
+	vu_log_debug (vui, "message too short (read %dB should be %dB)", rv,
+		      msg.size);
+	goto close_socket;
+      }
+  }
+
+  switch (msg.request)
+    {
+    case VHOST_USER_GET_FEATURES:
+      msg.flags |= 4;
+      msg.u64 = VIRTIO_FEATURE (VIRTIO_NET_F_MRG_RXBUF) |
+	VIRTIO_FEATURE (VIRTIO_NET_F_CTRL_VQ) |
+	VIRTIO_FEATURE (VIRTIO_F_ANY_LAYOUT) |
+	VIRTIO_FEATURE (VIRTIO_RING_F_INDIRECT_DESC) |
+	VIRTIO_FEATURE (VHOST_F_LOG_ALL) |
+	VIRTIO_FEATURE (VIRTIO_NET_F_GUEST_ANNOUNCE) |
+	VIRTIO_FEATURE (VIRTIO_NET_F_MQ) |
+	VIRTIO_FEATURE (VHOST_USER_F_PROTOCOL_FEATURES) |
+	VIRTIO_FEATURE (VIRTIO_F_VERSION_1);
+      msg.u64 &= vui->feature_mask;
+
+      if (vui->enable_event_idx)
+	msg.u64 |= VIRTIO_FEATURE (VIRTIO_RING_F_EVENT_IDX);
+      if (vui->enable_gso)
+	msg.u64 |= FEATURE_VIRTIO_NET_F_HOST_GUEST_TSO_FEATURE_BITS;
+      if (vui->enable_packed)
+	msg.u64 |= VIRTIO_FEATURE (VIRTIO_F_RING_PACKED);
+
+      msg.size = sizeof (msg.u64);
+      vu_log_debug (vui, "if %d msg VHOST_USER_GET_FEATURES - reply "
+		    "0x%016llx", vui->hw_if_index, msg.u64);
+      n =
+	send (uf->file_descriptor, &msg, VHOST_USER_MSG_HDR_SZ + msg.size, 0);
+      if (n != (msg.size + VHOST_USER_MSG_HDR_SZ))
+	{
+	  vu_log_debug (vui, "could not send message response");
+	  goto close_socket;
+	}
+      break;
+
+    case VHOST_USER_SET_FEATURES:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_FEATURES features "
+		    "0x%016llx", vui->hw_if_index, msg.u64);
+
+      vui->features = msg.u64;
+
+      if (vui->features &
+	  (VIRTIO_FEATURE (VIRTIO_NET_F_MRG_RXBUF) |
+	   VIRTIO_FEATURE (VIRTIO_F_VERSION_1)))
+	vui->virtio_net_hdr_sz = 12;
+      else
+	vui->virtio_net_hdr_sz = 10;
+
+      vui->is_any_layout =
+	(vui->features & VIRTIO_FEATURE (VIRTIO_F_ANY_LAYOUT)) ? 1 : 0;
+
+      ASSERT (vui->virtio_net_hdr_sz < VLIB_BUFFER_PRE_DATA_SIZE);
+      if (vui->enable_gso &&
+	  ((vui->features & FEATURE_VIRTIO_NET_F_HOST_GUEST_TSO_FEATURE_BITS)
+	   == FEATURE_VIRTIO_NET_F_HOST_GUEST_TSO_FEATURE_BITS))
+	{
+	  vnet_hw_if_set_caps (vnm, vui->hw_if_index,
+			       VNET_HW_IF_CAP_TCP_GSO |
+				 VNET_HW_IF_CAP_TX_TCP_CKSUM |
+				 VNET_HW_IF_CAP_TX_UDP_CKSUM);
+	}
+      else
+	{
+	  vnet_hw_if_unset_caps (vnm, vui->hw_if_index,
+				 VNET_HW_IF_CAP_TCP_GSO |
+				   VNET_HW_IF_CAP_L4_TX_CKSUM);
+	}
+      vnet_hw_interface_set_flags (vnm, vui->hw_if_index, 0);
+      vui->is_ready = 0;
+      vhost_user_update_iface_state (vui);
+      break;
+
+    case VHOST_USER_SET_MEM_TABLE:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_MEM_TABLE nregions %d",
+		    vui->hw_if_index, msg.memory.nregions);
+
+      if ((msg.memory.nregions < 1) ||
+	  (msg.memory.nregions > VHOST_MEMORY_MAX_NREGIONS))
+	{
+	  vu_log_debug (vui, "number of mem regions must be between 1 and %i",
+			VHOST_MEMORY_MAX_NREGIONS);
+	  goto close_socket;
+	}
+
+      if (msg.memory.nregions != number_of_fds)
+	{
+	  vu_log_debug (vui, "each memory region must have FD");
+	  goto close_socket;
+	}
+
+      /* Do the mmap without barrier sync */
+      void *region_mmap_addr[VHOST_MEMORY_MAX_NREGIONS];
+      for (i = 0; i < msg.memory.nregions; i++)
+	{
+	  long page_sz = get_huge_page_size (fds[i]);
+
+	  /* align size to page */
+	  ssize_t map_sz = (msg.memory.regions[i].memory_size +
+			    msg.memory.regions[i].mmap_offset +
+			    page_sz - 1) & ~(page_sz - 1);
+
+	  region_mmap_addr[i] = mmap (0, map_sz, PROT_READ | PROT_WRITE,
+				      MAP_SHARED, fds[i], 0);
+	  if (region_mmap_addr[i] == MAP_FAILED)
+	    {
+	      vu_log_err (vui, "failed to map memory. errno is %d", errno);
+	      for (j = 0; j < i; j++)
+		munmap (region_mmap_addr[j], map_sz);
+	      goto close_socket;
+	    }
+	  vu_log_debug (vui, "map memory region %d addr 0 len 0x%lx fd %d "
+			"mapped 0x%lx page_sz 0x%x", i, map_sz, fds[i],
+			region_mmap_addr[i], page_sz);
+	}
+
+      vlib_worker_thread_barrier_sync (vm);
+      unmap_all_mem_regions (vui);
+      for (i = 0; i < msg.memory.nregions; i++)
+	{
+	  clib_memcpy_fast (&(vui->regions[i]), &msg.memory.regions[i],
+			    sizeof (vhost_user_memory_region_t));
+
+	  vui->region_mmap_addr[i] = region_mmap_addr[i];
+	  vui->region_guest_addr_lo[i] = vui->regions[i].guest_phys_addr;
+	  vui->region_guest_addr_hi[i] = vui->regions[i].guest_phys_addr +
+	    vui->regions[i].memory_size;
+
+	  vui->region_mmap_addr[i] += vui->regions[i].mmap_offset;
+	  vui->region_mmap_fd[i] = fds[i];
+
+	  vui->nregions++;
+	}
+
+      /*
+       * Re-compute desc, used, and avail descriptor table if vring address
+       * is set.
+       */
+      FOR_ALL_VHOST_RX_TXQ (q, vui)
+      {
+	if (vui->vrings[q].desc_user_addr && vui->vrings[q].used_user_addr &&
+	    vui->vrings[q].avail_user_addr)
+	  {
+	    vui->vrings[q].desc =
+	      map_user_mem (vui, vui->vrings[q].desc_user_addr);
+	    vui->vrings[q].used =
+	      map_user_mem (vui, vui->vrings[q].used_user_addr);
+	    vui->vrings[q].avail =
+	      map_user_mem (vui, vui->vrings[q].avail_user_addr);
+	  }
+      }
+      vlib_worker_thread_barrier_release (vm);
+      break;
+
+    case VHOST_USER_SET_VRING_NUM:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_VRING_NUM idx %d num %d",
+		    vui->hw_if_index, msg.state.index, msg.state.num);
+
+      if ((msg.state.num > 32768) ||	/* maximum ring size is 32768 */
+	  (msg.state.num == 0) ||	/* it cannot be zero */
+	  ((msg.state.num - 1) & msg.state.num) ||	/* must be power of 2 */
+	  (msg.state.index >= vui->num_qid))
+	{
+	  vu_log_debug (vui, "invalid VHOST_USER_SET_VRING_NUM: msg.state.num"
+			" %d, msg.state.index %d, curruent max q %d",
+			msg.state.num, msg.state.index, vui->num_qid);
+	  goto close_socket;
+	}
+      vui->vrings[msg.state.index].qsz_mask = msg.state.num - 1;
+      break;
+
+    case VHOST_USER_SET_VRING_ADDR:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_VRING_ADDR idx %d",
+		    vui->hw_if_index, msg.state.index);
+
+      if (msg.state.index >= vui->num_qid)
+	{
+	  vu_log_debug (vui, "invalid vring index VHOST_USER_SET_VRING_ADDR:"
+			" %u >= %u", msg.state.index, vui->num_qid);
+	  goto close_socket;
+	}
+
+      if (msg.size < sizeof (msg.addr))
+	{
+	  vu_log_debug (vui, "vhost message is too short (%d < %d)",
+			msg.size, sizeof (msg.addr));
+	  goto close_socket;
+	}
+
+      vnet_virtio_vring_desc_t *desc =
+	map_user_mem (vui, msg.addr.desc_user_addr);
+      vnet_virtio_vring_used_t *used =
+	map_user_mem (vui, msg.addr.used_user_addr);
+      vnet_virtio_vring_avail_t *avail =
+	map_user_mem (vui, msg.addr.avail_user_addr);
+
+      if ((desc == NULL) || (used == NULL) || (avail == NULL))
+	{
+	  vu_log_debug (vui, "failed to map user memory for hw_if_index %d",
+			vui->hw_if_index);
+	  goto close_socket;
+	}
+
+      vui->vrings[msg.state.index].desc_user_addr = msg.addr.desc_user_addr;
+      vui->vrings[msg.state.index].used_user_addr = msg.addr.used_user_addr;
+      vui->vrings[msg.state.index].avail_user_addr = msg.addr.avail_user_addr;
+
+      vlib_worker_thread_barrier_sync (vm);
+      vui->vrings[msg.state.index].desc = desc;
+      vui->vrings[msg.state.index].used = used;
+      vui->vrings[msg.state.index].avail = avail;
+
+      vui->vrings[msg.state.index].log_guest_addr = msg.addr.log_guest_addr;
+      vui->vrings[msg.state.index].log_used =
+	(msg.addr.flags & (1 << VHOST_VRING_F_LOG)) ? 1 : 0;
+
+      /* Spec says: If VHOST_USER_F_PROTOCOL_FEATURES has not been negotiated,
+         the ring is initialized in an enabled state. */
+      if (!(vui->features & VIRTIO_FEATURE (VHOST_USER_F_PROTOCOL_FEATURES)))
+	vui->vrings[msg.state.index].enabled = 1;
+
+      vui->vrings[msg.state.index].last_used_idx =
+	vui->vrings[msg.state.index].last_avail_idx =
+	vui->vrings[msg.state.index].used->idx;
+      vui->vrings[msg.state.index].last_kick =
+	vui->vrings[msg.state.index].last_used_idx;
+
+      /* tell driver that we want interrupts or not */
+      vhost_user_set_operation_mode (vui, &vui->vrings[msg.state.index]);
+      vlib_worker_thread_barrier_release (vm);
+      vhost_user_update_iface_state (vui);
+      break;
+
+    case VHOST_USER_SET_OWNER:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_OWNER", vui->hw_if_index);
+      break;
+
+    case VHOST_USER_RESET_OWNER:
+      vu_log_debug (vui, "if %d msg VHOST_USER_RESET_OWNER",
+		    vui->hw_if_index);
+      break;
+
+    case VHOST_USER_SET_VRING_CALL:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_VRING_CALL %d",
+		    vui->hw_if_index, msg.u64);
+
+      q = (u8) (msg.u64 & 0xFF);
+      if (vui->num_qid > q)
+	{
+	  /* if there is old fd, delete and close it */
+	  if (vui->vrings[q].callfd_idx != ~0)
+	    {
+	      clib_file_t *uf = pool_elt_at_index (file_main.file_pool,
+						   vui->vrings[q].callfd_idx);
+	      clib_file_del (&file_main, uf);
+	      vui->vrings[q].callfd_idx = ~0;
+	    }
+	}
+      else if (vec_len (vui->vrings) > q)
+	{
+	  /* grow vrings by pair (RX + TX) */
+	  vui->num_qid = (q & 1) ? (q + 1) : (q + 2);
+	}
+      else
+	{
+	  u32 i, new_max_q, old_max_q = vec_len (vui->vrings);
+
+	  /*
+	   * Double the array size if it is less than 64 entries.
+	   * Slow down thereafter.
+	   */
+	  if (vec_len (vui->vrings) < (VHOST_VRING_INIT_MQ_PAIR_SZ << 3))
+	    new_max_q = vec_len (vui->vrings) << 1;
+	  else
+	    new_max_q = vec_len (vui->vrings) +
+	      (VHOST_VRING_INIT_MQ_PAIR_SZ << 2);
+	  if (new_max_q > (VHOST_VRING_MAX_MQ_PAIR_SZ << 1))
+	    new_max_q = (VHOST_VRING_MAX_MQ_PAIR_SZ << 1);
+
+	  /* sync with the worker threads, vrings may move due to realloc */
+	  vlib_worker_thread_barrier_sync (vm);
+	  vec_validate_aligned (vui->vrings, new_max_q - 1,
+				CLIB_CACHE_LINE_BYTES);
+	  vlib_worker_thread_barrier_release (vm);
+
+	  for (i = old_max_q; i < vec_len (vui->vrings); i++)
+	    vhost_user_vring_init (vui, i);
+
+	  /* grow vrings by pair (RX + TX) */
+	  vui->num_qid = (q & 1) ? (q + 1) : (q + 2);
+	}
+
+      if (!(msg.u64 & VHOST_USER_VRING_NOFD_MASK))
+	{
+	  if (number_of_fds != 1)
+	    {
+	      vu_log_debug (vui, "More than one fd received !");
+	      goto close_socket;
+	    }
+
+	  template.read_function = vhost_user_callfd_read_ready;
+	  template.file_descriptor = fds[0];
+	  template.private_data =
+	    ((vui - vhost_user_main.vhost_user_interfaces) << 8) + q;
+	  template.description = format (0, "vhost user");
+	  vui->vrings[q].callfd_idx = clib_file_add (&file_main, &template);
+	}
+      else
+	vui->vrings[q].callfd_idx = ~0;
+      break;
+
+    case VHOST_USER_SET_VRING_KICK:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_VRING_KICK %d",
+		    vui->hw_if_index, msg.u64);
+
+      q = (u8) (msg.u64 & 0xFF);
+      if (q >= vui->num_qid)
+	{
+	  vu_log_debug (vui, "invalid vring index VHOST_USER_SET_VRING_KICK:"
+			" %u >= %u", q, vui->num_qid);
+	  goto close_socket;
+	}
+
+      if (vui->vrings[q].kickfd_idx != ~0)
+	{
+	  clib_file_t *uf = pool_elt_at_index (file_main.file_pool,
+					       vui->vrings[q].kickfd_idx);
+	  clib_file_del (&file_main, uf);
+	  vui->vrings[q].kickfd_idx = ~0;
+	}
+
+      if (!(msg.u64 & VHOST_USER_VRING_NOFD_MASK))
+	{
+	  if (number_of_fds != 1)
+	    {
+	      vu_log_debug (vui, "More than one fd received !");
+	      goto close_socket;
+	    }
+
+	  template.read_function = vhost_user_kickfd_read_ready;
+	  template.file_descriptor = fds[0];
+	  template.private_data =
+	    (((uword) (vui - vhost_user_main.vhost_user_interfaces)) << 8) +
+	    q;
+	  vui->vrings[q].kickfd_idx = clib_file_add (&file_main, &template);
+	}
+      else
+	{
+	  //When no kickfd is set, the queue is initialized as started
+	  vui->vrings[q].kickfd_idx = ~0;
+	  vui->vrings[q].started = 1;
+	  vhost_user_thread_placement (vui, q);
+	}
+      vhost_user_update_iface_state (vui);
+      break;
+
+    case VHOST_USER_SET_VRING_ERR:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_VRING_ERR %d",
+		    vui->hw_if_index, msg.u64);
+
+      q = (u8) (msg.u64 & 0xFF);
+      if (q >= vui->num_qid)
+	{
+	  vu_log_debug (vui, "invalid vring index VHOST_USER_SET_VRING_ERR:"
+			" %u >= %u", q, vui->num_qid);
+	  goto close_socket;
+	}
+
+      if (vui->vrings[q].errfd != -1)
+	close (vui->vrings[q].errfd);
+
+      if (!(msg.u64 & VHOST_USER_VRING_NOFD_MASK))
+	{
+	  if (number_of_fds != 1)
+	    goto close_socket;
+
+	  vui->vrings[q].errfd = fds[0];
+	}
+      else
+	vui->vrings[q].errfd = -1;
+      break;
+
+    case VHOST_USER_SET_VRING_BASE:
+      vu_log_debug (vui,
+		    "if %d msg VHOST_USER_SET_VRING_BASE idx %d num 0x%x",
+		    vui->hw_if_index, msg.state.index, msg.state.num);
+      if (msg.state.index >= vui->num_qid)
+	{
+	  vu_log_debug (vui, "invalid vring index VHOST_USER_SET_VRING_ADDR:"
+			" %u >= %u", msg.state.index, vui->num_qid);
+	  goto close_socket;
+	}
+      vlib_worker_thread_barrier_sync (vm);
+      vui->vrings[msg.state.index].last_avail_idx = msg.state.num;
+      if (vhost_user_is_packed_ring_supported (vui))
+	{
+	  /*
+	   *  0                   1                   2                   3
+	   *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+	   * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   * |    last avail idx           | |     last used idx           | |
+	   * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   *                                ^                               ^
+	   *                                |                               |
+	   *                         avail wrap counter       used wrap counter
+	   */
+	  /* last avail idx at bit 0-14. */
+	  vui->vrings[msg.state.index].last_avail_idx =
+	    msg.state.num & 0x7fff;
+	  /* avail wrap counter at bit 15 */
+	  vui->vrings[msg.state.index].avail_wrap_counter =
+	    ! !(msg.state.num & (1 << 15));
+
+	  /*
+	   * Although last_used_idx is passed in the upper 16 bits in qemu
+	   * implementation, in practice, last_avail_idx and last_used_idx are
+	   * usually the same. As a result, DPDK does not bother to pass us
+	   * last_used_idx. The spec is not clear on thex coding. I figured it
+	   * out by reading the qemu code. So let's just read last_avail_idx
+	   * and set last_used_idx equals to last_avail_idx.
+	   */
+	  vui->vrings[msg.state.index].last_used_idx =
+	    vui->vrings[msg.state.index].last_avail_idx;
+	  vui->vrings[msg.state.index].last_kick =
+	    vui->vrings[msg.state.index].last_used_idx;
+	  vui->vrings[msg.state.index].used_wrap_counter =
+	    vui->vrings[msg.state.index].avail_wrap_counter;
+
+	  if (vui->vrings[msg.state.index].avail_wrap_counter == 1)
+	    vui->vrings[msg.state.index].avail_wrap_counter =
+	      VRING_DESC_F_AVAIL;
+	}
+      vlib_worker_thread_barrier_release (vm);
+      break;
+
+    case VHOST_USER_GET_VRING_BASE:
+      if (msg.state.index >= vui->num_qid)
+	{
+	  vu_log_debug (vui, "invalid vring index VHOST_USER_GET_VRING_BASE:"
+			" %u >= %u", msg.state.index, vui->num_qid);
+	  goto close_socket;
+	}
+
+      /* protection is needed to prevent rx/tx from changing last_avail_idx */
+      vlib_worker_thread_barrier_sync (vm);
+      /*
+       * Copy last_avail_idx from the vring before closing it because
+       * closing the vring also initializes the vring last_avail_idx
+       */
+      msg.state.num = vui->vrings[msg.state.index].last_avail_idx;
+      if (vhost_user_is_packed_ring_supported (vui))
+	{
+	  msg.state.num =
+	    (vui->vrings[msg.state.index].last_avail_idx & 0x7fff) |
+	    (! !vui->vrings[msg.state.index].avail_wrap_counter << 15);
+	  msg.state.num |=
+	    ((vui->vrings[msg.state.index].last_used_idx & 0x7fff) |
+	     (! !vui->vrings[msg.state.index].used_wrap_counter << 15)) << 16;
+	}
+      msg.flags |= 4;
+      msg.size = sizeof (msg.state);
+
+      /*
+       * Spec says: Client must [...] stop ring upon receiving
+       * VHOST_USER_GET_VRING_BASE
+       */
+      vhost_user_vring_close (vui, msg.state.index);
+      vlib_worker_thread_barrier_release (vm);
+      vu_log_debug (vui,
+		    "if %d msg VHOST_USER_GET_VRING_BASE idx %d num 0x%x",
+		    vui->hw_if_index, msg.state.index, msg.state.num);
+      n =
+	send (uf->file_descriptor, &msg, VHOST_USER_MSG_HDR_SZ + msg.size, 0);
+      if (n != (msg.size + VHOST_USER_MSG_HDR_SZ))
+	{
+	  vu_log_debug (vui, "could not send message response");
+	  goto close_socket;
+	}
+      vhost_user_update_iface_state (vui);
+      break;
+
+    case VHOST_USER_NONE:
+      vu_log_debug (vui, "if %d msg VHOST_USER_NONE", vui->hw_if_index);
+      break;
+
+    case VHOST_USER_SET_LOG_BASE:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_LOG_BASE",
+		    vui->hw_if_index);
+
+      if (msg.size != sizeof (msg.log))
+	{
+	  vu_log_debug (vui, "invalid msg size for VHOST_USER_SET_LOG_BASE:"
+			" %d instead of %d", msg.size, sizeof (msg.log));
+	  goto close_socket;
+	}
+
+      if (!(vui->protocol_features & (1 << VHOST_USER_PROTOCOL_F_LOG_SHMFD)))
+	{
+	  vu_log_debug (vui, "VHOST_USER_PROTOCOL_F_LOG_SHMFD not set but "
+			"VHOST_USER_SET_LOG_BASE received");
+	  goto close_socket;
+	}
+
+      fd = fds[0];
+      /* align size to page */
+      long page_sz = get_huge_page_size (fd);
+      ssize_t map_sz =
+	(msg.log.size + msg.log.offset + page_sz - 1) & ~(page_sz - 1);
+
+      void *log_base_addr = mmap (0, map_sz, PROT_READ | PROT_WRITE,
+				  MAP_SHARED, fd, 0);
+
+      vu_log_debug (vui, "map log region addr 0 len 0x%lx off 0x%lx fd %d "
+		    "mapped 0x%lx", map_sz, msg.log.offset, fd,
+		    log_base_addr);
+
+      if (log_base_addr == MAP_FAILED)
+	{
+	  vu_log_err (vui, "failed to map memory. errno is %d", errno);
+	  goto close_socket;
+	}
+
+      vlib_worker_thread_barrier_sync (vm);
+      vui->log_base_addr = log_base_addr;
+      vui->log_base_addr += msg.log.offset;
+      vui->log_size = msg.log.size;
+      vlib_worker_thread_barrier_release (vm);
+
+      msg.flags |= 4;
+      msg.size = sizeof (msg.u64);
+      n =
+	send (uf->file_descriptor, &msg, VHOST_USER_MSG_HDR_SZ + msg.size, 0);
+      if (n != (msg.size + VHOST_USER_MSG_HDR_SZ))
+	{
+	  vu_log_debug (vui, "could not send message response");
+	  goto close_socket;
+	}
+      break;
+
+    case VHOST_USER_SET_LOG_FD:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_LOG_FD", vui->hw_if_index);
+      break;
+
+    case VHOST_USER_GET_PROTOCOL_FEATURES:
+      msg.flags |= 4;
+      msg.u64 = (1 << VHOST_USER_PROTOCOL_F_LOG_SHMFD) |
+	(1 << VHOST_USER_PROTOCOL_F_MQ);
+      msg.size = sizeof (msg.u64);
+      vu_log_debug (vui, "if %d msg VHOST_USER_GET_PROTOCOL_FEATURES - "
+		    "reply 0x%016llx", vui->hw_if_index, msg.u64);
+      n =
+	send (uf->file_descriptor, &msg, VHOST_USER_MSG_HDR_SZ + msg.size, 0);
+      if (n != (msg.size + VHOST_USER_MSG_HDR_SZ))
+	{
+	  vu_log_debug (vui, "could not send message response");
+	  goto close_socket;
+	}
+      break;
+
+    case VHOST_USER_SET_PROTOCOL_FEATURES:
+      vu_log_debug (vui, "if %d msg VHOST_USER_SET_PROTOCOL_FEATURES "
+		    "features 0x%016llx", vui->hw_if_index, msg.u64);
+      vui->protocol_features = msg.u64;
+      break;
+
+    case VHOST_USER_GET_QUEUE_NUM:
+      msg.flags |= 4;
+      msg.u64 = VHOST_VRING_MAX_MQ_PAIR_SZ;
+      msg.size = sizeof (msg.u64);
+      vu_log_debug (vui, "if %d msg VHOST_USER_GET_QUEUE_NUM - reply %d",
+		    vui->hw_if_index, msg.u64);
+      n =
+	send (uf->file_descriptor, &msg, VHOST_USER_MSG_HDR_SZ + msg.size, 0);
+      if (n != (msg.size + VHOST_USER_MSG_HDR_SZ))
+	{
+	  vu_log_debug (vui, "could not send message response");
+	  goto close_socket;
+	}
+      break;
+
+    case VHOST_USER_SET_VRING_ENABLE:
+      vu_log_debug (vui, "if %d VHOST_USER_SET_VRING_ENABLE: %s queue %d",
+		    vui->hw_if_index, msg.state.num ? "enable" : "disable",
+		    msg.state.index);
+      if (msg.state.index >= vui->num_qid)
+	{
+	  vu_log_debug (vui, "invalid vring idx VHOST_USER_SET_VRING_ENABLE:"
+			" %u >= %u", msg.state.index, vui->num_qid);
+	  goto close_socket;
+	}
+
+      vui->vrings[msg.state.index].enabled = msg.state.num;
+      vhost_user_thread_placement (vui, msg.state.index);
+      vhost_user_update_iface_state (vui);
+      break;
+
+    default:
+      vu_log_debug (vui, "unknown vhost-user message %d received. "
+		    "closing socket", msg.request);
+      goto close_socket;
+    }
+
+  return 0;
+
+close_socket:
+  vlib_worker_thread_barrier_sync (vm);
+  vhost_user_if_disconnect (vui);
+  vlib_worker_thread_barrier_release (vm);
+  vhost_user_update_iface_state (vui);
+  return 0;
+}
+
+static clib_error_t *
+vhost_user_socket_error (clib_file_t * uf)
+{
+  vlib_main_t *vm = vlib_get_main ();
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui =
+    pool_elt_at_index (vum->vhost_user_interfaces, uf->private_data);
+
+  vu_log_debug (vui, "socket error on if %d", vui->sw_if_index);
+  vlib_worker_thread_barrier_sync (vm);
+  vhost_user_if_disconnect (vui);
+  vlib_worker_thread_barrier_release (vm);
+  return 0;
+}
+
+static clib_error_t *
+vhost_user_socksvr_accept_ready (clib_file_t * uf)
+{
+  int client_fd, client_len;
+  struct sockaddr_un client;
+  clib_file_t template = { 0 };
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui;
+
+  vui = pool_elt_at_index (vum->vhost_user_interfaces, uf->private_data);
+
+  client_len = sizeof (client);
+  client_fd = accept (uf->file_descriptor,
+		      (struct sockaddr *) &client,
+		      (socklen_t *) & client_len);
+
+  if (client_fd < 0)
+    return clib_error_return_unix (0, "accept");
+
+  if (vui->clib_file_index != ~0)
+    {
+      vu_log_debug (vui, "Close client socket for vhost interface %d, fd %d",
+		    vui->sw_if_index, UNIX_GET_FD (vui->clib_file_index));
+      clib_file_del (&file_main, file_main.file_pool + vui->clib_file_index);
+    }
+
+  vu_log_debug (vui, "New client socket for vhost interface %d, fd %d",
+		vui->sw_if_index, client_fd);
+  template.read_function = vhost_user_socket_read;
+  template.error_function = vhost_user_socket_error;
+  template.file_descriptor = client_fd;
+  template.private_data = vui - vhost_user_main.vhost_user_interfaces;
+  template.description = format (0, "vhost interface %d", vui->sw_if_index);
+  vui->clib_file_index = clib_file_add (&file_main, &template);
+  vui->num_qid = 2;
+  return 0;
+}
+
+static clib_error_t *
+vhost_user_init (vlib_main_t * vm)
+{
+  vhost_user_main_t *vum = &vhost_user_main;
+  vlib_thread_main_t *tm = vlib_get_thread_main ();
+
+  vum->log_default = vlib_log_register_class ("vhost-user", 0);
+
+  vum->coalesce_frames = 32;
+  vum->coalesce_time = 1e-3;
+
+  vec_validate (vum->cpus, tm->n_vlib_mains - 1);
+
+  vhost_cpu_t *cpu;
+  vec_foreach (cpu, vum->cpus)
+  {
+    /* This is actually not necessary as validate already zeroes it
+     * Just keeping the loop here for later because I am lazy. */
+    cpu->rx_buffers_len = 0;
+  }
+
+  vum->random = random_default_seed ();
+
+  mhash_init_c_string (&vum->if_index_by_sock_name, sizeof (uword));
+
+  return 0;
+}
+
+/* *INDENT-OFF* */
+VLIB_INIT_FUNCTION (vhost_user_init) =
+{
+  .runs_after = VLIB_INITS("ip4_init"),
+};
+/* *INDENT-ON* */
+
+static uword
+vhost_user_send_interrupt_process (vlib_main_t * vm,
+				   vlib_node_runtime_t * rt, vlib_frame_t * f)
+{
+  vhost_user_intf_t *vui;
+  f64 timeout = 3153600000.0 /* 100 years */ ;
+  uword event_type, *event_data = 0;
+  vhost_user_main_t *vum = &vhost_user_main;
+  u16 qid;
+  f64 now, poll_time_remaining;
+  f64 next_timeout;
+  u8 stop_timer = 0;
+
+  while (1)
+    {
+      poll_time_remaining =
+	vlib_process_wait_for_event_or_clock (vm, timeout);
+      event_type = vlib_process_get_events (vm, &event_data);
+      vec_reset_length (event_data);
+
+      /*
+       * Use the remaining timeout if it is less than coalesce time to avoid
+       * resetting the existing timer in the middle of expiration
+       */
+      timeout = poll_time_remaining;
+      if (vlib_process_suspend_time_is_zero (timeout) ||
+	  (timeout > vum->coalesce_time))
+	timeout = vum->coalesce_time;
+
+      now = vlib_time_now (vm);
+      switch (event_type)
+	{
+	case VHOST_USER_EVENT_STOP_TIMER:
+	  stop_timer = 1;
+	  break;
+
+	case VHOST_USER_EVENT_START_TIMER:
+	  stop_timer = 0;
+	  timeout = 1e-3;
+	  if (!vlib_process_suspend_time_is_zero (poll_time_remaining))
+	    break;
+	  /* fall through */
+
+	case ~0:
+	  /* *INDENT-OFF* */
+	  pool_foreach (vui, vum->vhost_user_interfaces) {
+	      next_timeout = timeout;
+	      FOR_ALL_VHOST_RX_TXQ (qid, vui)
+	      {
+		vhost_user_vring_t *vq = &vui->vrings[qid];
+
+		if (vq->started == 0)
+		  continue;
+		if (vq->n_since_last_int)
+		  {
+		    if (now >= vq->int_deadline)
+		      vhost_user_send_call (vm, vui, vq);
+		    else
+		      next_timeout = vq->int_deadline - now;
+		  }
+
+		if ((next_timeout < timeout) && (next_timeout > 0.0))
+		  timeout = next_timeout;
+	      }
+	  }
+          /* *INDENT-ON* */
+	  break;
+
+	default:
+	  clib_warning ("BUG: unhandled event type %d", event_type);
+	  break;
+	}
+      /* No less than 1 millisecond */
+      if (timeout < 1e-3)
+	timeout = 1e-3;
+      if (stop_timer)
+	timeout = 3153600000.0;
+    }
+  return 0;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (vhost_user_send_interrupt_node) = {
+    .function = vhost_user_send_interrupt_process,
+    .type = VLIB_NODE_TYPE_PROCESS,
+    .name = "vhost-user-send-interrupt-process",
+};
+/* *INDENT-ON* */
+
+static uword
+vhost_user_process (vlib_main_t * vm,
+		    vlib_node_runtime_t * rt, vlib_frame_t * f)
+{
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui;
+  struct sockaddr_un sun;
+  int sockfd;
+  clib_file_t template = { 0 };
+  f64 timeout = 3153600000.0 /* 100 years */ ;
+  uword *event_data = 0;
+
+  sockfd = -1;
+  sun.sun_family = AF_UNIX;
+  template.read_function = vhost_user_socket_read;
+  template.error_function = vhost_user_socket_error;
+
+  while (1)
+    {
+      vlib_process_wait_for_event_or_clock (vm, timeout);
+      vlib_process_get_events (vm, &event_data);
+      vec_reset_length (event_data);
+
+      timeout = 3.0;
+
+      /* *INDENT-OFF* */
+      pool_foreach (vui, vum->vhost_user_interfaces) {
+
+	  if (vui->unix_server_index == ~0) { //Nothing to do for server sockets
+	      if (vui->clib_file_index == ~0)
+		{
+		  if ((sockfd < 0) &&
+		      ((sockfd = socket (AF_UNIX, SOCK_STREAM, 0)) < 0))
+		    {
+		      /*
+		       * 1st time error or new error for this interface,
+		       * spit out the message and record the error
+		       */
+		      if (!vui->sock_errno || (vui->sock_errno != errno))
+			{
+			  clib_unix_warning
+			    ("Error: Could not open unix socket for %s",
+			     vui->sock_filename);
+			  vui->sock_errno = errno;
+			}
+		      continue;
+		    }
+
+		  /* try to connect */
+		  strncpy (sun.sun_path, (char *) vui->sock_filename,
+			   sizeof (sun.sun_path) - 1);
+		  sun.sun_path[sizeof (sun.sun_path) - 1] = 0;
+
+		  /* Avoid hanging VPP if the other end does not accept */
+		  if (fcntl(sockfd, F_SETFL, O_NONBLOCK) < 0)
+                      clib_unix_warning ("fcntl");
+
+		  if (connect (sockfd, (struct sockaddr *) &sun,
+			       sizeof (struct sockaddr_un)) == 0)
+		    {
+		      /* Set the socket to blocking as it was before */
+                      if (fcntl(sockfd, F_SETFL, 0) < 0)
+                        clib_unix_warning ("fcntl2");
+
+		      vui->sock_errno = 0;
+		      template.file_descriptor = sockfd;
+		      template.private_data =
+			  vui - vhost_user_main.vhost_user_interfaces;
+		      template.description = format (0, "vhost user process");
+		      vui->clib_file_index = clib_file_add (&file_main, &template);
+		      vui->num_qid = 2;
+
+		      /* This sockfd is considered consumed */
+		      sockfd = -1;
+		    }
+		  else
+		    {
+		      vui->sock_errno = errno;
+		    }
+		}
+	      else
+		{
+		  /* check if socket is alive */
+		  int error = 0;
+		  socklen_t len = sizeof (error);
+		  int fd = UNIX_GET_FD(vui->clib_file_index);
+		  int retval =
+		      getsockopt (fd, SOL_SOCKET, SO_ERROR, &error, &len);
+
+		  if (retval)
+		    {
+		      vu_log_debug (vui, "getsockopt returned %d", retval);
+		      vhost_user_if_disconnect (vui);
+		    }
+		}
+	  }
+      }
+      /* *INDENT-ON* */
+    }
+  return 0;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (vhost_user_process_node,static) = {
+    .function = vhost_user_process,
+    .type = VLIB_NODE_TYPE_PROCESS,
+    .name = "vhost-user-process",
+};
+/* *INDENT-ON* */
+
+/**
+ * Disables and reset interface structure.
+ * It can then be either init again, or removed from used interfaces.
+ */
+static void
+vhost_user_term_if (vhost_user_intf_t * vui)
+{
+  int q;
+  vhost_user_main_t *vum = &vhost_user_main;
+
+  // disconnect interface sockets
+  vhost_user_if_disconnect (vui);
+  vhost_user_update_gso_interface_count (vui, 0 /* delete */ );
+  vhost_user_update_iface_state (vui);
+
+  for (q = 0; q < vec_len (vui->vrings); q++)
+    clib_spinlock_free (&vui->vrings[q].vring_lock);
+
+  if (vui->unix_server_index != ~0)
+    {
+      //Close server socket
+      clib_file_t *uf = pool_elt_at_index (file_main.file_pool,
+					   vui->unix_server_index);
+      clib_file_del (&file_main, uf);
+      vui->unix_server_index = ~0;
+      unlink (vui->sock_filename);
+    }
+
+  mhash_unset (&vum->if_index_by_sock_name, vui->sock_filename,
+	       &vui->if_index);
+}
+
+int
+vhost_user_delete_if (vnet_main_t * vnm, vlib_main_t * vm, u32 sw_if_index)
+{
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui;
+  int rv = 0;
+  vnet_hw_interface_t *hwif;
+  u16 qid;
+
+  if (!
+      (hwif =
+       vnet_get_sup_hw_interface_api_visible_or_null (vnm, sw_if_index))
+      || hwif->dev_class_index != vhost_user_device_class.index)
+    return VNET_API_ERROR_INVALID_SW_IF_INDEX;
+
+  vui = pool_elt_at_index (vum->vhost_user_interfaces, hwif->dev_instance);
+
+  vu_log_debug (vui, "Deleting vhost-user interface %s (instance %d)",
+		hwif->name, hwif->dev_instance);
+
+  FOR_ALL_VHOST_TXQ (qid, vui)
+  {
+    vhost_user_vring_t *txvq = &vui->vrings[qid];
+
+    if ((txvq->mode == VNET_HW_IF_RX_MODE_POLLING) &&
+	(txvq->thread_index != ~0))
+      {
+	vhost_cpu_t *cpu = vec_elt_at_index (vum->cpus, txvq->thread_index);
+	ASSERT (cpu->polling_q_count != 0);
+	cpu->polling_q_count--;
+      }
+
+    if ((vum->ifq_count > 0) &&
+	((txvq->mode == VNET_HW_IF_RX_MODE_INTERRUPT) ||
+	 (txvq->mode == VNET_HW_IF_RX_MODE_ADAPTIVE)))
+      {
+	vum->ifq_count--;
+	// Stop the timer if there is no more interrupt interface/queue
+	if (vum->ifq_count == 0)
+	  {
+	    vlib_process_signal_event (vm,
+				       vhost_user_send_interrupt_node.index,
+				       VHOST_USER_EVENT_STOP_TIMER, 0);
+	    break;
+	  }
+      }
+  }
+
+  // Disable and reset interface
+  vhost_user_term_if (vui);
+
+  // Reset renumbered iface
+  if (hwif->dev_instance <
+      vec_len (vum->show_dev_instance_by_real_dev_instance))
+    vum->show_dev_instance_by_real_dev_instance[hwif->dev_instance] = ~0;
+
+  // Delete ethernet interface
+  ethernet_delete_interface (vnm, vui->hw_if_index);
+
+  // free vrings
+  vec_free (vui->vrings);
+
+  // Back to pool
+  pool_put (vum->vhost_user_interfaces, vui);
+
+  return rv;
+}
+
+static clib_error_t *
+vhost_user_exit (vlib_main_t * vm)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui;
+
+  vlib_worker_thread_barrier_sync (vlib_get_main ());
+  /* *INDENT-OFF* */
+  pool_foreach (vui, vum->vhost_user_interfaces) {
+      vhost_user_delete_if (vnm, vm, vui->sw_if_index);
+  }
+  /* *INDENT-ON* */
+  vlib_worker_thread_barrier_release (vlib_get_main ());
+  return 0;
+}
+
+VLIB_MAIN_LOOP_EXIT_FUNCTION (vhost_user_exit);
+
+/**
+ * Open server unix socket on specified sock_filename.
+ */
+static int
+vhost_user_init_server_sock (const char *sock_filename, int *sock_fd)
+{
+  int rv = 0;
+  struct sockaddr_un un = { };
+  int fd;
+  /* create listening socket */
+  if ((fd = socket (AF_UNIX, SOCK_STREAM, 0)) < 0)
+    return VNET_API_ERROR_SYSCALL_ERROR_1;
+
+  un.sun_family = AF_UNIX;
+  strncpy ((char *) un.sun_path, (char *) sock_filename,
+	   sizeof (un.sun_path) - 1);
+
+  /* remove if exists */
+  unlink ((char *) sock_filename);
+
+  if (bind (fd, (struct sockaddr *) &un, sizeof (un)) == -1)
+    {
+      rv = VNET_API_ERROR_SYSCALL_ERROR_2;
+      goto error;
+    }
+
+  if (listen (fd, 1) == -1)
+    {
+      rv = VNET_API_ERROR_SYSCALL_ERROR_3;
+      goto error;
+    }
+
+  *sock_fd = fd;
+  return 0;
+
+error:
+  close (fd);
+  return rv;
+}
+
+/**
+ * Create ethernet interface for vhost user interface.
+ */
+static void
+vhost_user_create_ethernet (vnet_main_t *vnm, vlib_main_t *vm,
+			    vhost_user_intf_t *vui,
+			    vhost_user_create_if_args_t *args)
+{
+  vhost_user_main_t *vum = &vhost_user_main;
+  vnet_eth_interface_registration_t eir = {};
+  u8 hwaddr[6];
+
+  /* create hw and sw interface */
+  if (args->use_custom_mac)
+    {
+      clib_memcpy (hwaddr, args->hwaddr, 6);
+    }
+  else
+    {
+      random_u32 (&vum->random);
+      clib_memcpy (hwaddr + 2, &vum->random, sizeof (vum->random));
+      hwaddr[0] = 2;
+      hwaddr[1] = 0xfe;
+    }
+
+  eir.dev_class_index = vhost_user_device_class.index;
+  eir.dev_instance = vui - vum->vhost_user_interfaces /* device instance */,
+  eir.address = hwaddr;
+  vui->hw_if_index = vnet_eth_register_interface (vnm, &eir);
+}
+
+/*
+ *  Initialize vui with specified attributes
+ */
+static void
+vhost_user_vui_init (vnet_main_t * vnm, vhost_user_intf_t * vui,
+		     int server_sock_fd, vhost_user_create_if_args_t * args,
+		     u32 * sw_if_index)
+{
+  vnet_sw_interface_t *sw;
+  int q;
+  vhost_user_main_t *vum = &vhost_user_main;
+
+  sw = vnet_get_hw_sw_interface (vnm, vui->hw_if_index);
+  if (server_sock_fd != -1)
+    {
+      clib_file_t template = { 0 };
+      template.read_function = vhost_user_socksvr_accept_ready;
+      template.file_descriptor = server_sock_fd;
+      template.private_data = vui - vum->vhost_user_interfaces;	//hw index
+      template.description = format (0, "vhost user %d", sw);
+      vui->unix_server_index = clib_file_add (&file_main, &template);
+    }
+  else
+    {
+      vui->unix_server_index = ~0;
+    }
+
+  vui->sw_if_index = sw->sw_if_index;
+  strncpy (vui->sock_filename, args->sock_filename,
+	   ARRAY_LEN (vui->sock_filename) - 1);
+  vui->sock_errno = 0;
+  vui->is_ready = 0;
+  vui->feature_mask = args->feature_mask;
+  vui->clib_file_index = ~0;
+  vui->log_base_addr = 0;
+  vui->if_index = vui - vum->vhost_user_interfaces;
+  vui->enable_gso = args->enable_gso;
+  vui->enable_event_idx = args->enable_event_idx;
+  vui->enable_packed = args->enable_packed;
+  /*
+   * enable_gso takes precedence over configurable feature mask if there
+   * is a clash.
+   *   if feature mask disables gso, but enable_gso is configured,
+   *     then gso is enable
+   *   if feature mask enables gso, but enable_gso is not configured,
+   *     then gso is enable
+   *
+   * if gso is enable via feature mask, it must enable both host and guest
+   * gso feature mask, we don't support one sided GSO or partial GSO.
+   */
+  if ((vui->enable_gso == 0) &&
+      ((args->feature_mask & FEATURE_VIRTIO_NET_F_HOST_GUEST_TSO_FEATURE_BITS)
+       == (FEATURE_VIRTIO_NET_F_HOST_GUEST_TSO_FEATURE_BITS)))
+    vui->enable_gso = 1;
+  vhost_user_update_gso_interface_count (vui, 1 /* add */ );
+  mhash_set_mem (&vum->if_index_by_sock_name, vui->sock_filename,
+		 &vui->if_index, 0);
+
+  vec_validate_aligned (vui->vrings, (VHOST_VRING_INIT_MQ_PAIR_SZ << 1) - 1,
+			CLIB_CACHE_LINE_BYTES);
+  vui->num_qid = 2;
+  for (q = 0; q < vec_len (vui->vrings); q++)
+    vhost_user_vring_init (vui, q);
+
+  vnet_hw_if_set_caps (vnm, vui->hw_if_index, VNET_HW_IF_CAP_INT_MODE);
+  vnet_hw_interface_set_flags (vnm, vui->hw_if_index, 0);
+
+  if (sw_if_index)
+    *sw_if_index = vui->sw_if_index;
+}
+
+int
+vhost_user_create_if (vnet_main_t * vnm, vlib_main_t * vm,
+		      vhost_user_create_if_args_t * args)
+{
+  vhost_user_intf_t *vui = NULL;
+  u32 sw_if_idx = ~0;
+  int rv = 0;
+  int server_sock_fd = -1;
+  vhost_user_main_t *vum = &vhost_user_main;
+  uword *if_index;
+
+  if (args->sock_filename == NULL || !(strlen (args->sock_filename) > 0))
+    {
+      return VNET_API_ERROR_INVALID_ARGUMENT;
+    }
+
+  if_index = mhash_get (&vum->if_index_by_sock_name,
+			(void *) args->sock_filename);
+  if (if_index)
+    {
+      vui = &vum->vhost_user_interfaces[*if_index];
+      args->sw_if_index = vui->sw_if_index;
+      return VNET_API_ERROR_IF_ALREADY_EXISTS;
+    }
+
+  if (args->is_server)
+    {
+      if ((rv =
+	   vhost_user_init_server_sock (args->sock_filename,
+					&server_sock_fd)) != 0)
+	{
+	  return rv;
+	}
+    }
+
+  /* Protect the uninitialized vui from being dispatched by rx/tx */
+  vlib_worker_thread_barrier_sync (vm);
+  pool_get (vhost_user_main.vhost_user_interfaces, vui);
+  vhost_user_create_ethernet (vnm, vm, vui, args);
+  vlib_worker_thread_barrier_release (vm);
+
+  vhost_user_vui_init (vnm, vui, server_sock_fd, args, &sw_if_idx);
+  vnet_sw_interface_set_mtu (vnm, vui->sw_if_index, 9000);
+  vhost_user_rx_thread_placement (vui, 1);
+
+  if (args->renumber)
+    vnet_interface_name_renumber (sw_if_idx, args->custom_dev_instance);
+
+  args->sw_if_index = sw_if_idx;
+
+  // Process node must connect
+  vlib_process_signal_event (vm, vhost_user_process_node.index, 0, 0);
+
+  return rv;
+}
+
+int
+vhost_user_modify_if (vnet_main_t * vnm, vlib_main_t * vm,
+		      vhost_user_create_if_args_t * args)
+{
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui = NULL;
+  u32 sw_if_idx = ~0;
+  int server_sock_fd = -1;
+  int rv = 0;
+  vnet_hw_interface_t *hwif;
+  uword *if_index;
+
+  if (!(hwif = vnet_get_sup_hw_interface_api_visible_or_null (vnm,
+							      args->sw_if_index))
+      || hwif->dev_class_index != vhost_user_device_class.index)
+    return VNET_API_ERROR_INVALID_SW_IF_INDEX;
+
+  if (args->sock_filename == NULL || !(strlen (args->sock_filename) > 0))
+    return VNET_API_ERROR_INVALID_ARGUMENT;
+
+  vui = vec_elt_at_index (vum->vhost_user_interfaces, hwif->dev_instance);
+
+  /*
+   * Disallow changing the interface to have the same path name
+   * as other interface
+   */
+  if_index = mhash_get (&vum->if_index_by_sock_name,
+			(void *) args->sock_filename);
+  if (if_index && (*if_index != vui->if_index))
+    return VNET_API_ERROR_IF_ALREADY_EXISTS;
+
+  // First try to open server socket
+  if (args->is_server)
+    if ((rv = vhost_user_init_server_sock (args->sock_filename,
+					   &server_sock_fd)) != 0)
+      return rv;
+
+  vhost_user_term_if (vui);
+  vhost_user_vui_init (vnm, vui, server_sock_fd, args, &sw_if_idx);
+
+  if (args->renumber)
+    vnet_interface_name_renumber (sw_if_idx, args->custom_dev_instance);
+
+  // Process node must connect
+  vlib_process_signal_event (vm, vhost_user_process_node.index, 0, 0);
+
+  return rv;
+}
+
+clib_error_t *
+vhost_user_connect_command_fn (vlib_main_t * vm,
+			       unformat_input_t * input,
+			       vlib_cli_command_t * cmd)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  unformat_input_t _line_input, *line_input = &_line_input;
+  clib_error_t *error = NULL;
+  vhost_user_create_if_args_t args = { 0 };
+  int rv;
+
+  /* Get a line of input. */
+  if (!unformat_user (input, unformat_line_input, line_input))
+    return 0;
+
+  args.feature_mask = (u64) ~ (0ULL);
+  args.custom_dev_instance = ~0;
+  /* GSO feature is disable by default */
+  args.feature_mask &= ~FEATURE_VIRTIO_NET_F_HOST_GUEST_TSO_FEATURE_BITS;
+  /* packed-ring feature is disable by default */
+  args.feature_mask &= ~VIRTIO_FEATURE (VIRTIO_F_RING_PACKED);
+  /* event_idx feature is disable by default */
+  args.feature_mask &= ~VIRTIO_FEATURE (VIRTIO_RING_F_EVENT_IDX);
+
+  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (line_input, "socket %s", &args.sock_filename))
+	;
+      else if (unformat (line_input, "server"))
+	args.is_server = 1;
+      else if (unformat (line_input, "gso"))
+	args.enable_gso = 1;
+      else if (unformat (line_input, "packed"))
+	args.enable_packed = 1;
+      else if (unformat (line_input, "event-idx"))
+	args.enable_event_idx = 1;
+      else if (unformat (line_input, "feature-mask 0x%llx",
+			 &args.feature_mask))
+	;
+      else if (unformat (line_input, "hwaddr %U", unformat_ethernet_address,
+			 args.hwaddr))
+	args.use_custom_mac = 1;
+      else if (unformat (line_input, "renumber %d",
+			 &args.custom_dev_instance))
+	args.renumber = 1;
+      else
+	{
+	  error = clib_error_return (0, "unknown input `%U'",
+				     format_unformat_error, line_input);
+	  goto done;
+	}
+    }
+
+  if ((rv = vhost_user_create_if (vnm, vm, &args)))
+    {
+      error = clib_error_return (0, "vhost_user_create_if returned %d", rv);
+      goto done;
+    }
+
+  vlib_cli_output (vm, "%U\n", format_vnet_sw_if_index_name, vnm,
+		   args.sw_if_index);
+
+done:
+  vec_free (args.sock_filename);
+  unformat_free (line_input);
+
+  return error;
+}
+
+clib_error_t *
+vhost_user_delete_command_fn (vlib_main_t * vm,
+			      unformat_input_t * input,
+			      vlib_cli_command_t * cmd)
+{
+  unformat_input_t _line_input, *line_input = &_line_input;
+  u32 sw_if_index = ~0;
+  vnet_main_t *vnm = vnet_get_main ();
+  clib_error_t *error = NULL;
+
+  /* Get a line of input. */
+  if (!unformat_user (input, unformat_line_input, line_input))
+    return 0;
+
+  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (line_input, "sw_if_index %d", &sw_if_index))
+	;
+      else if (unformat
+	       (line_input, "%U", unformat_vnet_sw_interface, vnm,
+		&sw_if_index))
+	{
+	  vnet_hw_interface_t *hwif =
+	    vnet_get_sup_hw_interface_api_visible_or_null (vnm, sw_if_index);
+	  if (hwif == NULL ||
+	      vhost_user_device_class.index != hwif->dev_class_index)
+	    {
+	      error = clib_error_return (0, "Not a vhost interface");
+	      goto done;
+	    }
+	}
+      else
+	{
+	  error = clib_error_return (0, "unknown input `%U'",
+				     format_unformat_error, line_input);
+	  goto done;
+	}
+    }
+
+  vhost_user_delete_if (vnm, vm, sw_if_index);
+
+done:
+  unformat_free (line_input);
+
+  return error;
+}
+
+int
+vhost_user_dump_ifs (vnet_main_t * vnm, vlib_main_t * vm,
+		     vhost_user_intf_details_t ** out_vuids)
+{
+  int rv = 0;
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui;
+  vhost_user_intf_details_t *r_vuids = NULL;
+  vhost_user_intf_details_t *vuid = NULL;
+  u32 *hw_if_indices = 0;
+  vnet_hw_interface_t *hi;
+  int i;
+
+  if (!out_vuids)
+    return -1;
+
+  pool_foreach (vui, vum->vhost_user_interfaces)
+    vec_add1 (hw_if_indices, vui->hw_if_index);
+
+  for (i = 0; i < vec_len (hw_if_indices); i++)
+    {
+      hi = vnet_get_hw_interface (vnm, hw_if_indices[i]);
+      vui = pool_elt_at_index (vum->vhost_user_interfaces, hi->dev_instance);
+
+      vec_add2 (r_vuids, vuid, 1);
+      vuid->sw_if_index = vui->sw_if_index;
+      vuid->virtio_net_hdr_sz = vui->virtio_net_hdr_sz;
+      vuid->features = vui->features;
+      vuid->num_regions = vui->nregions;
+      vuid->is_server = vui->unix_server_index != ~0;
+      vuid->sock_errno = vui->sock_errno;
+      snprintf ((char *) vuid->sock_filename, sizeof (vuid->sock_filename),
+		"%s", vui->sock_filename);
+      memcpy_s (vuid->if_name, sizeof (vuid->if_name), hi->name,
+		clib_min (vec_len (hi->name), sizeof (vuid->if_name) - 1));
+      vuid->if_name[sizeof (vuid->if_name) - 1] = 0;
+    }
+
+  vec_free (hw_if_indices);
+
+  *out_vuids = r_vuids;
+
+  return rv;
+}
+
+static u8 *
+format_vhost_user_desc (u8 * s, va_list * args)
+{
+  char *fmt = va_arg (*args, char *);
+  vhost_user_intf_t *vui = va_arg (*args, vhost_user_intf_t *);
+  vnet_virtio_vring_desc_t *desc_table =
+    va_arg (*args, vnet_virtio_vring_desc_t *);
+  int idx = va_arg (*args, int);
+  u32 *mem_hint = va_arg (*args, u32 *);
+
+  s = format (s, fmt, idx, desc_table[idx].addr, desc_table[idx].len,
+	      desc_table[idx].flags, desc_table[idx].next,
+	      pointer_to_uword (map_guest_mem (vui, desc_table[idx].addr,
+					       mem_hint)));
+  return s;
+}
+
+static void
+vhost_user_show_fds (vlib_main_t * vm, vhost_user_vring_t * vq)
+{
+  int kickfd = UNIX_GET_FD (vq->kickfd_idx);
+  int callfd = UNIX_GET_FD (vq->callfd_idx);
+
+  vlib_cli_output (vm, "  kickfd %d callfd %d errfd %d\n", kickfd, callfd,
+		   vq->errfd);
+}
+
+static void
+vhost_user_show_desc (vlib_main_t * vm, vhost_user_intf_t * vui, int q,
+		      int show_descr, int show_verbose)
+{
+  int j;
+  u32 mem_hint = 0;
+  u32 idx;
+  u32 n_entries;
+  vnet_virtio_vring_desc_t *desc_table;
+  vhost_user_vring_t *vq = &vui->vrings[q];
+
+  if (vq->avail && vq->used)
+    vlib_cli_output (vm,
+		     "  avail.flags %x avail event idx %u avail.idx %d "
+		     "used.flags %x used event idx %u used.idx %d\n",
+		     vq->avail->flags, vhost_user_avail_event_idx (vq),
+		     vq->avail->idx, vq->used->flags,
+		     vhost_user_used_event_idx (vq), vq->used->idx);
+
+  vhost_user_show_fds (vm, vq);
+
+  if (show_descr)
+    {
+      vlib_cli_output (vm, "\n  descriptor table:\n");
+      vlib_cli_output (vm,
+		       "  slot         addr         len  flags  next      "
+		       "user_addr\n");
+      vlib_cli_output (vm,
+		       "  ===== ================== ===== ====== ===== "
+		       "==================\n");
+      for (j = 0; j < vq->qsz_mask + 1; j++)
+	{
+	  desc_table = vq->desc;
+	  vlib_cli_output (vm, "%U", format_vhost_user_desc,
+			   "  %-5d 0x%016lx %-5d 0x%04x %-5d 0x%016lx\n", vui,
+			   desc_table, j, &mem_hint);
+	  if (show_verbose && (desc_table[j].flags & VRING_DESC_F_INDIRECT))
+	    {
+	      n_entries =
+		desc_table[j].len / sizeof (vnet_virtio_vring_desc_t);
+	      desc_table = map_guest_mem (vui, desc_table[j].addr, &mem_hint);
+	      if (desc_table)
+		{
+		  for (idx = 0; idx < clib_min (20, n_entries); idx++)
+		    {
+		      vlib_cli_output
+			(vm, "%U", format_vhost_user_desc,
+			 ">  %-4u 0x%016lx %-5u 0x%04x %-5u 0x%016lx\n", vui,
+			 desc_table, idx, &mem_hint);
+		    }
+		  if (n_entries >= 20)
+		    vlib_cli_output (vm, "Skip displaying entries 20...%u\n",
+				     n_entries);
+		}
+	    }
+	}
+    }
+}
+
+static u8 *
+format_vhost_user_packed_desc (u8 * s, va_list * args)
+{
+  char *fmt = va_arg (*args, char *);
+  vhost_user_intf_t *vui = va_arg (*args, vhost_user_intf_t *);
+  vnet_virtio_vring_packed_desc_t *desc_table =
+    va_arg (*args, vnet_virtio_vring_packed_desc_t *);
+  int idx = va_arg (*args, int);
+  u32 *mem_hint = va_arg (*args, u32 *);
+
+  s = format (s, fmt, idx, desc_table[idx].addr, desc_table[idx].len,
+	      desc_table[idx].flags, desc_table[idx].id,
+	      pointer_to_uword (map_guest_mem (vui, desc_table[idx].addr,
+					       mem_hint)));
+  return s;
+}
+
+static u8 *
+format_vhost_user_event_idx_flags (u8 * s, va_list * args)
+{
+  u32 flags = va_arg (*args, u32);
+  typedef struct
+  {
+    u8 value;
+    char *str;
+  } event_idx_flags;
+  static event_idx_flags event_idx_array[] = {
+#define _(s,v) { .str = #s, .value = v, },
+    foreach_virtio_event_idx_flags
+#undef _
+  };
+  u32 num_entries = sizeof (event_idx_array) / sizeof (event_idx_flags);
+
+  if (flags < num_entries)
+    s = format (s, "%s", event_idx_array[flags].str);
+  else
+    s = format (s, "%u", flags);
+  return s;
+}
+
+static void
+vhost_user_show_desc_packed (vlib_main_t * vm, vhost_user_intf_t * vui, int q,
+			     int show_descr, int show_verbose)
+{
+  int j;
+  u32 mem_hint = 0;
+  u32 idx;
+  u32 n_entries;
+  vnet_virtio_vring_packed_desc_t *desc_table;
+  vhost_user_vring_t *vq = &vui->vrings[q];
+  u16 off_wrap, event_idx;
+
+  off_wrap = vq->avail_event->off_wrap;
+  event_idx = off_wrap & 0x7fff;
+  vlib_cli_output (vm, "  avail_event.flags %U avail_event.off_wrap %u "
+		   "avail event idx %u\n", format_vhost_user_event_idx_flags,
+		   (u32) vq->avail_event->flags, off_wrap, event_idx);
+
+  off_wrap = vq->used_event->off_wrap;
+  event_idx = off_wrap & 0x7fff;
+  vlib_cli_output (vm, "  used_event.flags %U used_event.off_wrap %u "
+		   "used event idx %u\n", format_vhost_user_event_idx_flags,
+		   (u32) vq->used_event->flags, off_wrap, event_idx);
+
+  vlib_cli_output (vm, "  avail wrap counter %u, used wrap counter %u\n",
+		   vq->avail_wrap_counter, vq->used_wrap_counter);
+
+  vhost_user_show_fds (vm, vq);
+
+  if (show_descr)
+    {
+      vlib_cli_output (vm, "\n  descriptor table:\n");
+      vlib_cli_output (vm,
+		       "  slot         addr         len  flags  id    "
+		       "user_addr\n");
+      vlib_cli_output (vm,
+		       "  ===== ================== ===== ====== ===== "
+		       "==================\n");
+      for (j = 0; j < vq->qsz_mask + 1; j++)
+	{
+	  desc_table = vq->packed_desc;
+	  vlib_cli_output (vm, "%U", format_vhost_user_packed_desc,
+			   "  %-5u 0x%016lx %-5u 0x%04x %-5u 0x%016lx\n", vui,
+			   desc_table, j, &mem_hint);
+	  if (show_verbose && (desc_table[j].flags & VRING_DESC_F_INDIRECT))
+	    {
+	      n_entries = desc_table[j].len >> 4;
+	      desc_table = map_guest_mem (vui, desc_table[j].addr, &mem_hint);
+	      if (desc_table)
+		{
+		  for (idx = 0; idx < clib_min (20, n_entries); idx++)
+		    {
+		      vlib_cli_output
+			(vm, "%U", format_vhost_user_packed_desc,
+			 ">  %-4u 0x%016lx %-5u 0x%04x %-5u 0x%016lx\n", vui,
+			 desc_table, idx, &mem_hint);
+		    }
+		  if (n_entries >= 20)
+		    vlib_cli_output (vm, "Skip displaying entries 20...%u\n",
+				     n_entries);
+		}
+	    }
+	}
+    }
+}
+
+clib_error_t *
+show_vhost_user_command_fn (vlib_main_t * vm,
+			    unformat_input_t * input,
+			    vlib_cli_command_t * cmd)
+{
+  clib_error_t *error = 0;
+  vnet_main_t *vnm = vnet_get_main ();
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui;
+  u32 hw_if_index, *hw_if_indices = 0;
+  vnet_hw_interface_t *hi;
+  u16 qid;
+  int i, j, q;
+  int show_descr = 0;
+  int show_verbose = 0;
+  struct feat_struct
+  {
+    u8 bit;
+    char *str;
+  };
+  struct feat_struct *feat_entry;
+
+  static struct feat_struct feat_array[] = {
+#define _(s,b) { .str = #s, .bit = b, },
+    foreach_virtio_net_features
+#undef _
+    {.str = NULL}
+  };
+
+#define foreach_protocol_feature \
+  _(VHOST_USER_PROTOCOL_F_MQ) \
+  _(VHOST_USER_PROTOCOL_F_LOG_SHMFD)
+
+  static struct feat_struct proto_feat_array[] = {
+#define _(s) { .str = #s, .bit = s},
+    foreach_protocol_feature
+#undef _
+    {.str = NULL}
+  };
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat
+	  (input, "%U", unformat_vnet_hw_interface, vnm, &hw_if_index))
+	{
+	  hi = vnet_get_hw_interface (vnm, hw_if_index);
+	  if (vhost_user_device_class.index != hi->dev_class_index)
+	    {
+	      error = clib_error_return (0, "unknown input `%U'",
+					 format_unformat_error, input);
+	      goto done;
+	    }
+	  vec_add1 (hw_if_indices, hw_if_index);
+	}
+      else if (unformat (input, "descriptors") || unformat (input, "desc"))
+	show_descr = 1;
+      else if (unformat (input, "verbose"))
+	show_verbose = 1;
+      else
+	{
+	  error = clib_error_return (0, "unknown input `%U'",
+				     format_unformat_error, input);
+	  goto done;
+	}
+    }
+  if (vec_len (hw_if_indices) == 0)
+    {
+      pool_foreach (vui, vum->vhost_user_interfaces)
+	vec_add1 (hw_if_indices, vui->hw_if_index);
+    }
+  vlib_cli_output (vm, "Virtio vhost-user interfaces");
+  vlib_cli_output (vm, "Global:\n  coalesce frames %d time %e",
+		   vum->coalesce_frames, vum->coalesce_time);
+  vlib_cli_output (vm, "  Number of rx virtqueues in interrupt mode: %d",
+		   vum->ifq_count);
+  vlib_cli_output (vm, "  Number of GSO interfaces: %d", vum->gso_count);
+  for (u32 tid = 0; tid <= vlib_num_workers (); tid++)
+    {
+      vhost_cpu_t *cpu = vec_elt_at_index (vum->cpus, tid);
+      vlib_cli_output (vm, "  Thread %u: Polling queue count %u", tid,
+		       cpu->polling_q_count);
+    }
+
+  for (i = 0; i < vec_len (hw_if_indices); i++)
+    {
+      hi = vnet_get_hw_interface (vnm, hw_if_indices[i]);
+      vui = pool_elt_at_index (vum->vhost_user_interfaces, hi->dev_instance);
+      vlib_cli_output (vm, "Interface: %U (ifindex %d)",
+		       format_vnet_hw_if_index_name, vnm, hw_if_indices[i],
+		       hw_if_indices[i]);
+      vlib_cli_output (vm, "  Number of qids %u", vui->num_qid);
+      if (vui->enable_gso)
+	vlib_cli_output (vm, "  GSO enable");
+      if (vui->enable_packed)
+	vlib_cli_output (vm, "  Packed ring enable");
+      if (vui->enable_event_idx)
+	vlib_cli_output (vm, "  Event index enable");
+
+      vlib_cli_output (vm, "virtio_net_hdr_sz %d\n"
+		       " features mask (0x%llx): \n"
+		       " features (0x%llx): \n",
+		       vui->virtio_net_hdr_sz, vui->feature_mask,
+		       vui->features);
+
+      feat_entry = (struct feat_struct *) &feat_array;
+      while (feat_entry->str)
+	{
+	  if (vui->features & (1ULL << feat_entry->bit))
+	    vlib_cli_output (vm, "   %s (%d)", feat_entry->str,
+			     feat_entry->bit);
+	  feat_entry++;
+	}
+
+      vlib_cli_output (vm, "  protocol features (0x%llx)",
+		       vui->protocol_features);
+      feat_entry = (struct feat_struct *) &proto_feat_array;
+      while (feat_entry->str)
+	{
+	  if (vui->protocol_features & (1ULL << feat_entry->bit))
+	    vlib_cli_output (vm, "   %s (%d)", feat_entry->str,
+			     feat_entry->bit);
+	  feat_entry++;
+	}
+
+      vlib_cli_output (vm, "\n");
+
+      vlib_cli_output (vm, " socket filename %s type %s errno \"%s\"\n\n",
+		       vui->sock_filename,
+		       (vui->unix_server_index != ~0) ? "server" : "client",
+		       strerror (vui->sock_errno));
+
+      vlib_cli_output (vm, " rx placement: ");
+
+      FOR_ALL_VHOST_TXQ (qid, vui)
+      {
+	vhost_user_vring_t *txvq = &vui->vrings[qid];
+
+	if (txvq->qid == -1)
+	  continue;
+	vlib_cli_output (vm, "   thread %d on vring %d, %U\n",
+			 txvq->thread_index, qid, format_vnet_hw_if_rx_mode,
+			 txvq->mode);
+      }
+
+      vlib_cli_output (vm, " tx placement\n");
+
+      FOR_ALL_VHOST_RXQ (qid, vui)
+      {
+	vhost_user_vring_t *rxvq = &vui->vrings[qid];
+	vnet_hw_if_tx_queue_t *txq;
+
+	if (rxvq->queue_index == ~0)
+	  continue;
+	txq = vnet_hw_if_get_tx_queue (vnm, rxvq->queue_index);
+	if (txq->threads)
+	  vlib_cli_output (vm, "   threads %U on vring %u: %s\n",
+			   format_bitmap_list, txq->threads, qid,
+			   txq->shared_queue ? "spin-lock" : "lock-free");
+      }
+
+      vlib_cli_output (vm, "\n");
+
+      vlib_cli_output (vm, " Memory regions (total %d)\n", vui->nregions);
+
+      if (vui->nregions)
+	{
+	  vlib_cli_output (vm,
+			   " region fd    guest_phys_addr    memory_size        userspace_addr     mmap_offset        mmap_addr\n");
+	  vlib_cli_output (vm,
+			   " ====== ===== ================== ================== ================== ================== ==================\n");
+	}
+      for (j = 0; j < vui->nregions; j++)
+	{
+	  vlib_cli_output (vm,
+			   "  %d     %-5d 0x%016lx 0x%016lx 0x%016lx 0x%016lx 0x%016lx\n",
+			   j, vui->region_mmap_fd[j],
+			   vui->regions[j].guest_phys_addr,
+			   vui->regions[j].memory_size,
+			   vui->regions[j].userspace_addr,
+			   vui->regions[j].mmap_offset,
+			   pointer_to_uword (vui->region_mmap_addr[j]));
+	}
+      FOR_ALL_VHOST_RX_TXQ (q, vui)
+      {
+	if (!vui->vrings[q].started)
+	  continue;
+
+	vlib_cli_output (vm, "\n Virtqueue %d (%s%s)\n", q,
+			 (q & 1) ? "RX" : "TX",
+			 vui->vrings[q].enabled ? "" : " disabled");
+	vlib_cli_output (vm, "  global %s queue index %u\n",
+			 (q & 1) ? "RX" : "TX", vui->vrings[q].queue_index);
+
+	vlib_cli_output (
+	  vm,
+	  "  qsz %d last_avail_idx %d last_used_idx %d"
+	  " last_kick %u\n",
+	  vui->vrings[q].qsz_mask + 1, vui->vrings[q].last_avail_idx,
+	  vui->vrings[q].last_used_idx, vui->vrings[q].last_kick);
+
+	if (vhost_user_is_packed_ring_supported (vui))
+	  vhost_user_show_desc_packed (vm, vui, q, show_descr, show_verbose);
+	else
+	  vhost_user_show_desc (vm, vui, q, show_descr, show_verbose);
+      }
+      vlib_cli_output (vm, "\n");
+    }
+done:
+  vec_free (hw_if_indices);
+  return error;
+}
+
+/*
+ * CLI functions
+ */
+
+/*?
+ * Create a vHost User interface. Once created, a new virtual interface
+ * will exist with the name '<em>VirtualEthernet0/0/x</em>', where '<em>x</em>'
+ * is the next free index.
+ *
+ * There are several parameters associated with a vHost interface:
+ *
+ * - <b>socket <socket-filename></b> - Name of the linux socket used by
+ * hypervisor and VPP to manage the vHost interface. If in <em>server</em>
+ * mode, VPP will create the socket if it does not already exist. If in
+ * <em>client</em> mode, hypervisor will create the socket if it does not
+ * already exist. The VPP code is indifferent to the file location. However,
+ * if SELinux is enabled, then the socket needs to be created in
+ * <em>/var/run/vpp/</em>.
+ *
+ * - <b>server</b> - Optional flag to indicate that VPP should be the server
+ * for the linux socket. If not provided, VPP will be the client. In
+ * <em>server</em> mode, the VM can be reset without tearing down the vHost
+ * Interface. In <em>client</em> mode, VPP can be reset without bringing down
+ * the VM and tearing down the vHost Interface.
+ *
+ * - <b>feature-mask <hex></b> - Optional virtio/vhost feature set negotiated
+ * at startup. <b>This is intended for degugging only.</b> It is recommended
+ * that this parameter not be used except by experienced users. By default,
+ * all supported features will be advertised. Otherwise, provide the set of
+ * features desired.
+ *   - 0x000008000 (15) - VIRTIO_NET_F_MRG_RXBUF
+ *   - 0x000020000 (17) - VIRTIO_NET_F_CTRL_VQ
+ *   - 0x000200000 (21) - VIRTIO_NET_F_GUEST_ANNOUNCE
+ *   - 0x000400000 (22) - VIRTIO_NET_F_MQ
+ *   - 0x004000000 (26) - VHOST_F_LOG_ALL
+ *   - 0x008000000 (27) - VIRTIO_F_ANY_LAYOUT
+ *   - 0x010000000 (28) - VIRTIO_F_INDIRECT_DESC
+ *   - 0x040000000 (30) - VHOST_USER_F_PROTOCOL_FEATURES
+ *   - 0x100000000 (32) - VIRTIO_F_VERSION_1
+ *
+ * - <b>hwaddr <mac-addr></b> - Optional ethernet address, can be in either
+ * X:X:X:X:X:X unix or X.X.X cisco format.
+ *
+ * - <b>renumber <dev_instance></b> - Optional parameter which allows the
+ * instance in the name to be specified. If instance already exists, name
+ * will be used anyway and multiple instances will have the same name. Use
+ * with caution.
+ *
+ * @cliexpar
+ * Example of how to create a vhost interface with VPP as the client and all
+ * features enabled:
+ * @cliexstart{create vhost-user socket /var/run/vpp/vhost1.sock}
+ * VirtualEthernet0/0/0
+ * @cliexend
+ * Example of how to create a vhost interface with VPP as the server and with
+ * just multiple queues enabled:
+ * @cliexstart{create vhost-user socket /var/run/vpp/vhost2.sock server
+ * feature-mask 0x40400000}
+ * VirtualEthernet0/0/1
+ * @cliexend
+ * Once the vHost interface is created, enable the interface using:
+ * @cliexcmd{set interface state VirtualEthernet0/0/0 up}
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (vhost_user_connect_command, static) = {
+    .path = "create vhost-user",
+    .short_help = "create vhost-user socket <socket-filename> [server] "
+    "[feature-mask <hex>] [hwaddr <mac-addr>] [renumber <dev_instance>] [gso] "
+    "[packed] [event-idx]",
+    .function = vhost_user_connect_command_fn,
+    .is_mp_safe = 1,
+};
+/* *INDENT-ON* */
+
+/*?
+ * Delete a vHost User interface using the interface name or the
+ * software interface index. Use the '<em>show interface</em>'
+ * command to determine the software interface index. On deletion,
+ * the linux socket will not be deleted.
+ *
+ * @cliexpar
+ * Example of how to delete a vhost interface by name:
+ * @cliexcmd{delete vhost-user VirtualEthernet0/0/1}
+ * Example of how to delete a vhost interface by software interface index:
+ * @cliexcmd{delete vhost-user sw_if_index 1}
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (vhost_user_delete_command, static) = {
+    .path = "delete vhost-user",
+    .short_help = "delete vhost-user {<interface> | sw_if_index <sw_idx>}",
+    .function = vhost_user_delete_command_fn,
+};
+
+/*?
+ * Display the attributes of a single vHost User interface (provide interface
+ * name), multiple vHost User interfaces (provide a list of interface names
+ * separated by spaces) or all Vhost User interfaces (omit an interface name
+ * to display all vHost interfaces).
+ *
+ * @cliexpar
+ * @parblock
+ * Example of how to display a vhost interface:
+ * @cliexstart{show vhost-user VirtualEthernet0/0/0}
+ * Virtio vhost-user interfaces
+ * Global:
+ *   coalesce frames 32 time 1e-3
+ * Interface: VirtualEthernet0/0/0 (ifindex 1)
+ * virtio_net_hdr_sz 12
+ *  features mask (0xffffffffffffffff):
+ *  features (0x50408000):
+ *    VIRTIO_NET_F_MRG_RXBUF (15)
+ *    VIRTIO_NET_F_MQ (22)
+ *    VIRTIO_F_INDIRECT_DESC (28)
+ *    VHOST_USER_F_PROTOCOL_FEATURES (30)
+ *   protocol features (0x3)
+ *    VHOST_USER_PROTOCOL_F_MQ (0)
+ *    VHOST_USER_PROTOCOL_F_LOG_SHMFD (1)
+ *
+ *  socket filename /var/run/vpp/vhost1.sock type client errno "Success"
+ *
+ * rx placement:
+ *    thread 1 on vring 1
+ *    thread 1 on vring 5
+ *    thread 2 on vring 3
+ *    thread 2 on vring 7
+ *  tx placement: spin-lock
+ *    thread 0 on vring 0
+ *    thread 1 on vring 2
+ *    thread 2 on vring 0
+ *
+ * Memory regions (total 2)
+ * region fd guest_phys_addr memory_size userspace_addr mmap_offset mmap_addr
+ * ====== == =============== =========== ============== =========== ==========
+ *   0    60  0x00000000     0x000a0000  0xaac00000     0x00000000  0x2b400000
+ *   1    61  0x000c0000     0x3ff40000  0xaacc0000     0x000c0000  0xabcc0000
+ *
+ *  Virtqueue 0 (TX)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *   avail.flags 1 avail.idx 128 used.flags 1 used.idx 0
+ *   kickfd 62 callfd 64 errfd -1
+ *
+ *  Virtqueue 1 (RX)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *   avail.flags 1 avail.idx 0 used.flags 1 used.idx 0
+ *   kickfd 65 callfd 66 errfd -1
+ *
+ *  Virtqueue 2 (TX)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *   avail.flags 1 avail.idx 128 used.flags 1 used.idx 0
+ *   kickfd 63 callfd 70 errfd -1
+ *
+ *  Virtqueue 3 (RX)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *   avail.flags 1 avail.idx 0 used.flags 1 used.idx 0
+ *   kickfd 72 callfd 74 errfd -1
+ *
+ *  Virtqueue 4 (TX disabled)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *   avail.flags 1 avail.idx 0 used.flags 1 used.idx 0
+ *   kickfd 76 callfd 78 errfd -1
+ *
+ *  Virtqueue 5 (RX disabled)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *   avail.flags 1 avail.idx 0 used.flags 1 used.idx 0
+ *   kickfd 80 callfd 82 errfd -1
+ *
+ *  Virtqueue 6 (TX disabled)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *  avail.flags 1 avail.idx 0 used.flags 1 used.idx 0
+ *   kickfd 84 callfd 86 errfd -1
+ *
+ *  Virtqueue 7 (RX disabled)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *   avail.flags 1 avail.idx 0 used.flags 1 used.idx 0
+ *   kickfd 88 callfd 90 errfd -1
+ *
+ * @cliexend
+ *
+ * The optional '<em>descriptors</em>' parameter will display the same output
+ * as the previous example but will include the descriptor table for each
+ * queue.
+ * The output is truncated below:
+ * @cliexstart{show vhost-user VirtualEthernet0/0/0 descriptors}
+ * Virtio vhost-user interfaces
+ * Global:
+ *   coalesce frames 32 time 1e-3
+ * Interface: VirtualEthernet0/0/0 (ifindex 1)
+ * virtio_net_hdr_sz 12
+ *  features mask (0xffffffffffffffff):
+ *  features (0x50408000):
+ *    VIRTIO_NET_F_MRG_RXBUF (15)
+ *    VIRTIO_NET_F_MQ (22)
+ * :
+ *  Virtqueue 0 (TX)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ *   avail.flags 1 avail.idx 128 used.flags 1 used.idx 0
+ *   kickfd 62 callfd 64 errfd -1
+ *
+ *   descriptor table:
+ *    id          addr         len  flags  next      user_addr
+ *   ===== ================== ===== ====== ===== ==================
+ *   0     0x0000000010b6e974 2060  0x0002 1     0x00002aabbc76e974
+ *   1     0x0000000010b6e034 2060  0x0002 2     0x00002aabbc76e034
+ *   2     0x0000000010b6d6f4 2060  0x0002 3     0x00002aabbc76d6f4
+ *   3     0x0000000010b6cdb4 2060  0x0002 4     0x00002aabbc76cdb4
+ *   4     0x0000000010b6c474 2060  0x0002 5     0x00002aabbc76c474
+ *   5     0x0000000010b6bb34 2060  0x0002 6     0x00002aabbc76bb34
+ *   6     0x0000000010b6b1f4 2060  0x0002 7     0x00002aabbc76b1f4
+ *   7     0x0000000010b6a8b4 2060  0x0002 8     0x00002aabbc76a8b4
+ *   8     0x0000000010b69f74 2060  0x0002 9     0x00002aabbc769f74
+ *   9     0x0000000010b69634 2060  0x0002 10    0x00002aabbc769634
+ *   10    0x0000000010b68cf4 2060  0x0002 11    0x00002aabbc768cf4
+ * :
+ *   249   0x0000000000000000 0     0x0000 250   0x00002aab2b400000
+ *   250   0x0000000000000000 0     0x0000 251   0x00002aab2b400000
+ *   251   0x0000000000000000 0     0x0000 252   0x00002aab2b400000
+ *   252   0x0000000000000000 0     0x0000 253   0x00002aab2b400000
+ *   253   0x0000000000000000 0     0x0000 254   0x00002aab2b400000
+ *   254   0x0000000000000000 0     0x0000 255   0x00002aab2b400000
+ *   255   0x0000000000000000 0     0x0000 32768 0x00002aab2b400000
+ *
+ *  Virtqueue 1 (RX)
+ *   qsz 256 last_avail_idx 0 last_used_idx 0
+ * :
+ * @cliexend
+ * @endparblock
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (show_vhost_user_command, static) = {
+    .path = "show vhost-user",
+    .short_help = "show vhost-user [<interface> [<interface> [..]]] "
+    "[[descriptors] [verbose]]",
+    .function = show_vhost_user_command_fn,
+};
+/* *INDENT-ON* */
+
+
+static clib_error_t *
+vhost_user_config (vlib_main_t * vm, unformat_input_t * input)
+{
+  vhost_user_main_t *vum = &vhost_user_main;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "coalesce-frames %d", &vum->coalesce_frames))
+	;
+      else if (unformat (input, "coalesce-time %f", &vum->coalesce_time))
+	;
+      else if (unformat (input, "dont-dump-memory"))
+	vum->dont_dump_vhost_user_memory = 1;
+      else
+	return clib_error_return (0, "unknown input `%U'",
+				  format_unformat_error, input);
+    }
+
+  return 0;
+}
+
+/* vhost-user { ... } configuration. */
+VLIB_CONFIG_FUNCTION (vhost_user_config, "vhost-user");
+
+void
+vhost_user_unmap_all (void)
+{
+  vhost_user_main_t *vum = &vhost_user_main;
+  vhost_user_intf_t *vui;
+
+  if (vum->dont_dump_vhost_user_memory)
+    {
+      pool_foreach (vui, vum->vhost_user_interfaces)
+	unmap_all_mem_regions (vui);
+    }
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */