New upstream version 18.11-rc3
[deb_dpdk.git] / lib / librte_vhost / vhost_user.c
index 90ed211..3ea64eb 100644 (file)
@@ -1,5 +1,22 @@
 /* SPDX-License-Identifier: BSD-3-Clause
- * Copyright(c) 2010-2016 Intel Corporation
+ * Copyright(c) 2010-2018 Intel Corporation
+ */
+
+/* Security model
+ * --------------
+ * The vhost-user protocol connection is an external interface, so it must be
+ * robust against invalid inputs.
+ *
+ * This is important because the vhost-user master is only one step removed
+ * from the guest.  Malicious guests that have escaped will then launch further
+ * attacks from the vhost-user master.
+ *
+ * Even in deployments where guests are trusted, a bug in the vhost-user master
+ * can still cause invalid messages to be sent.  Such messages must not
+ * compromise the stability of the DPDK application by causing crashes, memory
+ * corruption, or other problematic behavior.
+ *
+ * Do not assume received VhostUserMsg fields contain sensible values!
  */
 
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/syscall.h>
 #include <assert.h>
 #ifdef RTE_LIBRTE_VHOST_NUMA
 #include <numaif.h>
 #endif
+#ifdef RTE_LIBRTE_VHOST_POSTCOPY
+#include <linux/userfaultfd.h>
+#endif
 
 #include <rte_common.h>
 #include <rte_malloc.h>
@@ -50,8 +73,16 @@ static const char *vhost_message_str[VHOST_USER_MAX] = {
        [VHOST_USER_NET_SET_MTU]  = "VHOST_USER_NET_SET_MTU",
        [VHOST_USER_SET_SLAVE_REQ_FD]  = "VHOST_USER_SET_SLAVE_REQ_FD",
        [VHOST_USER_IOTLB_MSG]  = "VHOST_USER_IOTLB_MSG",
+       [VHOST_USER_CRYPTO_CREATE_SESS] = "VHOST_USER_CRYPTO_CREATE_SESS",
+       [VHOST_USER_CRYPTO_CLOSE_SESS] = "VHOST_USER_CRYPTO_CLOSE_SESS",
+       [VHOST_USER_POSTCOPY_ADVISE]  = "VHOST_USER_POSTCOPY_ADVISE",
+       [VHOST_USER_POSTCOPY_LISTEN]  = "VHOST_USER_POSTCOPY_LISTEN",
+       [VHOST_USER_POSTCOPY_END]  = "VHOST_USER_POSTCOPY_END",
 };
 
+static int send_vhost_reply(int sockfd, struct VhostUserMsg *msg);
+static int read_vhost_message(int sockfd, struct VhostUserMsg *msg);
+
 static uint64_t
 get_blk_size(int fd)
 {
@@ -101,6 +132,13 @@ vhost_backend_cleanup(struct virtio_net *dev)
                close(dev->slave_req_fd);
                dev->slave_req_fd = -1;
        }
+
+       if (dev->postcopy_ufd >= 0) {
+               close(dev->postcopy_ufd);
+               dev->postcopy_ufd = -1;
+       }
+
+       dev->postcopy_listening = 0;
 }
 
 /*
@@ -108,55 +146,88 @@ vhost_backend_cleanup(struct virtio_net *dev)
  * the device hasn't been initialised.
  */
 static int
-vhost_user_set_owner(void)
+vhost_user_set_owner(struct virtio_net **pdev __rte_unused,
+                       struct VhostUserMsg *msg __rte_unused,
+                       int main_fd __rte_unused)
 {
-       return 0;
+       return VH_RESULT_OK;
 }
 
 static int
-vhost_user_reset_owner(struct virtio_net *dev)
+vhost_user_reset_owner(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg __rte_unused,
+                       int main_fd __rte_unused)
 {
-       if (dev->flags & VIRTIO_DEV_RUNNING) {
-               dev->flags &= ~VIRTIO_DEV_RUNNING;
-               dev->notify_ops->destroy_device(dev->vid);
-       }
+       struct virtio_net *dev = *pdev;
+       vhost_destroy_device_notify(dev);
 
        cleanup_device(dev, 0);
        reset_device(dev);
-       return 0;
+       return VH_RESULT_OK;
 }
 
 /*
  * The features that we support are requested.
  */
-static uint64_t
-vhost_user_get_features(struct virtio_net *dev)
+static int
+vhost_user_get_features(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        uint64_t features = 0;
 
        rte_vhost_driver_get_features(dev->ifname, &features);
-       return features;
+
+       msg->payload.u64 = features;
+       msg->size = sizeof(msg->payload.u64);
+       msg->fd_num = 0;
+
+       return VH_RESULT_REPLY;
+}
+
+/*
+ * The queue number that we support are requested.
+ */
+static int
+vhost_user_get_queue_num(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
+{
+       struct virtio_net *dev = *pdev;
+       uint32_t queue_num = 0;
+
+       rte_vhost_driver_get_queue_num(dev->ifname, &queue_num);
+
+       msg->payload.u64 = (uint64_t)queue_num;
+       msg->size = sizeof(msg->payload.u64);
+       msg->fd_num = 0;
+
+       return VH_RESULT_REPLY;
 }
 
 /*
  * We receive the negotiated features supported by us and the virtio device.
  */
 static int
-vhost_user_set_features(struct virtio_net *dev, uint64_t features)
+vhost_user_set_features(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
+       uint64_t features = msg->payload.u64;
        uint64_t vhost_features = 0;
+       struct rte_vdpa_device *vdpa_dev;
+       int did = -1;
 
        rte_vhost_driver_get_features(dev->ifname, &vhost_features);
        if (features & ~vhost_features) {
                RTE_LOG(ERR, VHOST_CONFIG,
                        "(%d) received invalid negotiated features.\n",
                        dev->vid);
-               return -1;
+               return VH_RESULT_ERR;
        }
 
        if (dev->flags & VIRTIO_DEV_RUNNING) {
                if (dev->features == features)
-                       return 0;
+                       return VH_RESULT_OK;
 
                /*
                 * Error out if master tries to change features while device is
@@ -167,7 +238,7 @@ vhost_user_set_features(struct virtio_net *dev, uint64_t features)
                        RTE_LOG(ERR, VHOST_CONFIG,
                                "(%d) features changed while device is running.\n",
                                dev->vid);
-                       return -1;
+                       return VH_RESULT_ERR;
                }
 
                if (dev->notify_ops->features_changed)
@@ -181,7 +252,7 @@ vhost_user_set_features(struct virtio_net *dev, uint64_t features)
        } else {
                dev->vhost_hlen = sizeof(struct virtio_net_hdr);
        }
-       LOG_DEBUG(VHOST_CONFIG,
+       VHOST_LOG_DEBUG(VHOST_CONFIG,
                "(%d) mergeable RX buffers %s, virtio 1 %s\n",
                dev->vid,
                (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? "on" : "off",
@@ -203,24 +274,42 @@ vhost_user_set_features(struct virtio_net *dev, uint64_t features)
 
                        dev->virtqueue[dev->nr_vring] = NULL;
                        cleanup_vq(vq, 1);
-                       free_vq(vq);
+                       free_vq(dev, vq);
                }
        }
 
-       return 0;
+       did = dev->vdpa_dev_id;
+       vdpa_dev = rte_vdpa_get_device(did);
+       if (vdpa_dev && vdpa_dev->ops->set_features)
+               vdpa_dev->ops->set_features(dev->vid);
+
+       return VH_RESULT_OK;
 }
 
 /*
  * The virtio device sends us the size of the descriptor ring.
  */
 static int
-vhost_user_set_vring_num(struct virtio_net *dev,
-                        VhostUserMsg *msg)
+vhost_user_set_vring_num(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        struct vhost_virtqueue *vq = dev->virtqueue[msg->payload.state.index];
 
        vq->size = msg->payload.state.num;
 
+       /* VIRTIO 1.0, 2.4 Virtqueues says:
+        *
+        *   Queue Size value is always a power of 2. The maximum Queue Size
+        *   value is 32768.
+        */
+       if ((vq->size & (vq->size - 1)) || vq->size > 32768) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "invalid virtqueue size %u\n", vq->size);
+               return VH_RESULT_ERR;
+       }
+
        if (dev->dequeue_zero_copy) {
                vq->nr_zmbuf = 0;
                vq->last_zmbuf_idx = 0;
@@ -236,13 +325,26 @@ vhost_user_set_vring_num(struct virtio_net *dev,
                TAILQ_INIT(&vq->zmbuf_list);
        }
 
-       vq->shadow_used_ring = rte_malloc(NULL,
+       if (vq_is_packed(dev)) {
+               vq->shadow_used_packed = rte_malloc(NULL,
+                               vq->size *
+                               sizeof(struct vring_used_elem_packed),
+                               RTE_CACHE_LINE_SIZE);
+               if (!vq->shadow_used_packed) {
+                       RTE_LOG(ERR, VHOST_CONFIG,
+                                       "failed to allocate memory for shadow used ring.\n");
+                       return VH_RESULT_ERR;
+               }
+
+       } else {
+               vq->shadow_used_split = rte_malloc(NULL,
                                vq->size * sizeof(struct vring_used_elem),
                                RTE_CACHE_LINE_SIZE);
-       if (!vq->shadow_used_ring) {
-               RTE_LOG(ERR, VHOST_CONFIG,
-                       "failed to allocate memory for shadow used ring.\n");
-               return -1;
+               if (!vq->shadow_used_split) {
+                       RTE_LOG(ERR, VHOST_CONFIG,
+                                       "failed to allocate memory for shadow used ring.\n");
+                       return VH_RESULT_ERR;
+               }
        }
 
        vq->batch_copy_elems = rte_malloc(NULL,
@@ -251,10 +353,10 @@ vhost_user_set_vring_num(struct virtio_net *dev,
        if (!vq->batch_copy_elems) {
                RTE_LOG(ERR, VHOST_CONFIG,
                        "failed to allocate memory for batching copy.\n");
-               return -1;
+               return VH_RESULT_ERR;
        }
 
-       return 0;
+       return VH_RESULT_OK;
 }
 
 /*
@@ -269,7 +371,8 @@ numa_realloc(struct virtio_net *dev, int index)
        struct virtio_net *old_dev;
        struct vhost_virtqueue *old_vq, *vq;
        struct zcopy_mbuf *new_zmbuf;
-       struct vring_used_elem *new_shadow_used_ring;
+       struct vring_used_elem *new_shadow_used_split;
+       struct vring_used_elem_packed *new_shadow_used_packed;
        struct batch_copy_elem *new_batch_copy_elems;
        int ret;
 
@@ -297,20 +400,35 @@ numa_realloc(struct virtio_net *dev, int index)
                memcpy(vq, old_vq, sizeof(*vq));
                TAILQ_INIT(&vq->zmbuf_list);
 
-               new_zmbuf = rte_malloc_socket(NULL, vq->zmbuf_size *
-                       sizeof(struct zcopy_mbuf), 0, newnode);
-               if (new_zmbuf) {
-                       rte_free(vq->zmbufs);
-                       vq->zmbufs = new_zmbuf;
+               if (dev->dequeue_zero_copy) {
+                       new_zmbuf = rte_malloc_socket(NULL, vq->zmbuf_size *
+                                       sizeof(struct zcopy_mbuf), 0, newnode);
+                       if (new_zmbuf) {
+                               rte_free(vq->zmbufs);
+                               vq->zmbufs = new_zmbuf;
+                       }
                }
 
-               new_shadow_used_ring = rte_malloc_socket(NULL,
-                       vq->size * sizeof(struct vring_used_elem),
-                       RTE_CACHE_LINE_SIZE,
-                       newnode);
-               if (new_shadow_used_ring) {
-                       rte_free(vq->shadow_used_ring);
-                       vq->shadow_used_ring = new_shadow_used_ring;
+               if (vq_is_packed(dev)) {
+                       new_shadow_used_packed = rte_malloc_socket(NULL,
+                                       vq->size *
+                                       sizeof(struct vring_used_elem_packed),
+                                       RTE_CACHE_LINE_SIZE,
+                                       newnode);
+                       if (new_shadow_used_packed) {
+                               rte_free(vq->shadow_used_packed);
+                               vq->shadow_used_packed = new_shadow_used_packed;
+                       }
+               } else {
+                       new_shadow_used_split = rte_malloc_socket(NULL,
+                                       vq->size *
+                                       sizeof(struct vring_used_elem),
+                                       RTE_CACHE_LINE_SIZE,
+                                       newnode);
+                       if (new_shadow_used_split) {
+                               rte_free(vq->shadow_used_split);
+                               vq->shadow_used_split = new_shadow_used_split;
+                       }
                }
 
                new_batch_copy_elems = rte_malloc_socket(NULL,
@@ -366,21 +484,26 @@ numa_realloc(struct virtio_net *dev, int index __rte_unused)
 
 /* Converts QEMU virtual address to Vhost virtual address. */
 static uint64_t
-qva_to_vva(struct virtio_net *dev, uint64_t qva)
+qva_to_vva(struct virtio_net *dev, uint64_t qva, uint64_t *len)
 {
-       struct rte_vhost_mem_region *reg;
+       struct rte_vhost_mem_region *r;
        uint32_t i;
 
        /* Find the region where the address lives. */
        for (i = 0; i < dev->mem->nregions; i++) {
-               reg = &dev->mem->regions[i];
+               r = &dev->mem->regions[i];
+
+               if (qva >= r->guest_user_addr &&
+                   qva <  r->guest_user_addr + r->size) {
 
-               if (qva >= reg->guest_user_addr &&
-                   qva <  reg->guest_user_addr + reg->size) {
-                       return qva - reg->guest_user_addr +
-                              reg->host_user_addr;
+                       if (unlikely(*len > r->guest_user_addr + r->size - qva))
+                               *len = r->guest_user_addr + r->size - qva;
+
+                       return qva - r->guest_user_addr +
+                              r->host_user_addr;
                }
        }
+       *len = 0;
 
        return 0;
 }
@@ -393,20 +516,20 @@ qva_to_vva(struct virtio_net *dev, uint64_t qva)
  */
 static uint64_t
 ring_addr_to_vva(struct virtio_net *dev, struct vhost_virtqueue *vq,
-               uint64_t ra, uint64_t size)
+               uint64_t ra, uint64_t *size)
 {
        if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)) {
                uint64_t vva;
 
                vva = vhost_user_iotlb_cache_find(vq, ra,
-                                       &size, VHOST_ACCESS_RW);
+                                       size, VHOST_ACCESS_RW);
                if (!vva)
                        vhost_user_iotlb_miss(dev, ra, VHOST_ACCESS_RW);
 
                return vva;
        }
 
-       return qva_to_vva(dev, ra);
+       return qva_to_vva(dev, ra, size);
 }
 
 static struct virtio_net *
@@ -414,16 +537,63 @@ translate_ring_addresses(struct virtio_net *dev, int vq_index)
 {
        struct vhost_virtqueue *vq = dev->virtqueue[vq_index];
        struct vhost_vring_addr *addr = &vq->ring_addrs;
+       uint64_t len;
+
+       if (vq_is_packed(dev)) {
+               len = sizeof(struct vring_packed_desc) * vq->size;
+               vq->desc_packed = (struct vring_packed_desc *)(uintptr_t)
+                       ring_addr_to_vva(dev, vq, addr->desc_user_addr, &len);
+               vq->log_guest_addr = 0;
+               if (vq->desc_packed == NULL ||
+                               len != sizeof(struct vring_packed_desc) *
+                               vq->size) {
+                       RTE_LOG(DEBUG, VHOST_CONFIG,
+                               "(%d) failed to map desc_packed ring.\n",
+                               dev->vid);
+                       return dev;
+               }
+
+               dev = numa_realloc(dev, vq_index);
+               vq = dev->virtqueue[vq_index];
+               addr = &vq->ring_addrs;
+
+               len = sizeof(struct vring_packed_desc_event);
+               vq->driver_event = (struct vring_packed_desc_event *)
+                                       (uintptr_t)ring_addr_to_vva(dev,
+                                       vq, addr->avail_user_addr, &len);
+               if (vq->driver_event == NULL ||
+                               len != sizeof(struct vring_packed_desc_event)) {
+                       RTE_LOG(DEBUG, VHOST_CONFIG,
+                               "(%d) failed to find driver area address.\n",
+                               dev->vid);
+                       return dev;
+               }
+
+               len = sizeof(struct vring_packed_desc_event);
+               vq->device_event = (struct vring_packed_desc_event *)
+                                       (uintptr_t)ring_addr_to_vva(dev,
+                                       vq, addr->used_user_addr, &len);
+               if (vq->device_event == NULL ||
+                               len != sizeof(struct vring_packed_desc_event)) {
+                       RTE_LOG(DEBUG, VHOST_CONFIG,
+                               "(%d) failed to find device area address.\n",
+                               dev->vid);
+                       return dev;
+               }
+
+               return dev;
+       }
 
        /* The addresses are converted from QEMU virtual to Vhost virtual. */
        if (vq->desc && vq->avail && vq->used)
                return dev;
 
+       len = sizeof(struct vring_desc) * vq->size;
        vq->desc = (struct vring_desc *)(uintptr_t)ring_addr_to_vva(dev,
-                       vq, addr->desc_user_addr, sizeof(struct vring_desc));
-       if (vq->desc == 0) {
+                       vq, addr->desc_user_addr, &len);
+       if (vq->desc == 0 || len != sizeof(struct vring_desc) * vq->size) {
                RTE_LOG(DEBUG, VHOST_CONFIG,
-                       "(%d) failed to find desc ring address.\n",
+                       "(%d) failed to map desc ring.\n",
                        dev->vid);
                return dev;
        }
@@ -432,20 +602,26 @@ translate_ring_addresses(struct virtio_net *dev, int vq_index)
        vq = dev->virtqueue[vq_index];
        addr = &vq->ring_addrs;
 
+       len = sizeof(struct vring_avail) + sizeof(uint16_t) * vq->size;
        vq->avail = (struct vring_avail *)(uintptr_t)ring_addr_to_vva(dev,
-                       vq, addr->avail_user_addr, sizeof(struct vring_avail));
-       if (vq->avail == 0) {
+                       vq, addr->avail_user_addr, &len);
+       if (vq->avail == 0 ||
+                       len != sizeof(struct vring_avail) +
+                       sizeof(uint16_t) * vq->size) {
                RTE_LOG(DEBUG, VHOST_CONFIG,
-                       "(%d) failed to find avail ring address.\n",
+                       "(%d) failed to map avail ring.\n",
                        dev->vid);
                return dev;
        }
 
+       len = sizeof(struct vring_used) +
+               sizeof(struct vring_used_elem) * vq->size;
        vq->used = (struct vring_used *)(uintptr_t)ring_addr_to_vva(dev,
-                       vq, addr->used_user_addr, sizeof(struct vring_used));
-       if (vq->used == 0) {
+                       vq, addr->used_user_addr, &len);
+       if (vq->used == 0 || len != sizeof(struct vring_used) +
+                       sizeof(struct vring_used_elem) * vq->size) {
                RTE_LOG(DEBUG, VHOST_CONFIG,
-                       "(%d) failed to find used ring address.\n",
+                       "(%d) failed to map used ring.\n",
                        dev->vid);
                return dev;
        }
@@ -461,13 +637,13 @@ translate_ring_addresses(struct virtio_net *dev, int vq_index)
 
        vq->log_guest_addr = addr->log_guest_addr;
 
-       LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address desc: %p\n",
+       VHOST_LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address desc: %p\n",
                        dev->vid, vq->desc);
-       LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address avail: %p\n",
+       VHOST_LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address avail: %p\n",
                        dev->vid, vq->avail);
-       LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address used: %p\n",
+       VHOST_LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address used: %p\n",
                        dev->vid, vq->used);
-       LOG_DEBUG(VHOST_CONFIG, "(%d) log_guest_addr: %" PRIx64 "\n",
+       VHOST_LOG_DEBUG(VHOST_CONFIG, "(%d) log_guest_addr: %" PRIx64 "\n",
                        dev->vid, vq->log_guest_addr);
 
        return dev;
@@ -478,14 +654,15 @@ translate_ring_addresses(struct virtio_net *dev, int vq_index)
  * This function then converts these to our address space.
  */
 static int
-vhost_user_set_vring_addr(struct virtio_net **pdev, VhostUserMsg *msg)
+vhost_user_set_vring_addr(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        struct vhost_virtqueue *vq;
        struct vhost_vring_addr *addr = &msg->payload.addr;
-       struct virtio_net *dev = *pdev;
 
        if (dev->mem == NULL)
-               return -1;
+               return VH_RESULT_ERR;
 
        /* addr->index refers to the queue index. The txq 1, rxq is 0. */
        vq = dev->virtqueue[msg->payload.addr.index];
@@ -500,32 +677,51 @@ vhost_user_set_vring_addr(struct virtio_net **pdev, VhostUserMsg *msg)
 
        if (vq->enabled && (dev->features &
                                (1ULL << VHOST_USER_F_PROTOCOL_FEATURES))) {
-               dev = translate_ring_addresses(dev, msg->payload.state.index);
+               dev = translate_ring_addresses(dev, msg->payload.addr.index);
                if (!dev)
-                       return -1;
+                       return VH_RESULT_ERR;
 
                *pdev = dev;
        }
 
-       return 0;
+       return VH_RESULT_OK;
 }
 
 /*
  * The virtio device sends us the available ring last used index.
  */
 static int
-vhost_user_set_vring_base(struct virtio_net *dev,
-                         VhostUserMsg *msg)
+vhost_user_set_vring_base(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
-       dev->virtqueue[msg->payload.state.index]->last_used_idx  =
-                       msg->payload.state.num;
-       dev->virtqueue[msg->payload.state.index]->last_avail_idx =
-                       msg->payload.state.num;
+       struct virtio_net *dev = *pdev;
+       struct vhost_virtqueue *vq = dev->virtqueue[msg->payload.state.index];
+       uint64_t val = msg->payload.state.num;
 
-       return 0;
+       if (vq_is_packed(dev)) {
+               /*
+                * Bit[0:14]: avail index
+                * Bit[15]: avail wrap counter
+                */
+               vq->last_avail_idx = val & 0x7fff;
+               vq->avail_wrap_counter = !!(val & (0x1 << 15));
+               /*
+                * Set used index to same value as available one, as
+                * their values should be the same since ring processing
+                * was stopped at get time.
+                */
+               vq->last_used_idx = vq->last_avail_idx;
+               vq->used_wrap_counter = vq->avail_wrap_counter;
+       } else {
+               vq->last_used_idx = msg->payload.state.num;
+               vq->last_avail_idx = msg->payload.state.num;
+       }
+
+       return VH_RESULT_OK;
 }
 
-static void
+static int
 add_one_guest_page(struct virtio_net *dev, uint64_t guest_phys_addr,
                   uint64_t host_phys_addr, uint64_t size)
 {
@@ -535,6 +731,10 @@ add_one_guest_page(struct virtio_net *dev, uint64_t guest_phys_addr,
                dev->max_guest_pages *= 2;
                dev->guest_pages = realloc(dev->guest_pages,
                                        dev->max_guest_pages * sizeof(*page));
+               if (!dev->guest_pages) {
+                       RTE_LOG(ERR, VHOST_CONFIG, "cannot realloc guest_pages\n");
+                       return -1;
+               }
        }
 
        if (dev->nr_guest_pages > 0) {
@@ -543,7 +743,7 @@ add_one_guest_page(struct virtio_net *dev, uint64_t guest_phys_addr,
                if (host_phys_addr == last_page->host_phys_addr +
                                      last_page->size) {
                        last_page->size += size;
-                       return;
+                       return 0;
                }
        }
 
@@ -551,9 +751,11 @@ add_one_guest_page(struct virtio_net *dev, uint64_t guest_phys_addr,
        page->guest_phys_addr = guest_phys_addr;
        page->host_phys_addr  = host_phys_addr;
        page->size = size;
+
+       return 0;
 }
 
-static void
+static int
 add_guest_pages(struct virtio_net *dev, struct rte_vhost_mem_region *reg,
                uint64_t page_size)
 {
@@ -567,7 +769,9 @@ add_guest_pages(struct virtio_net *dev, struct rte_vhost_mem_region *reg,
        size = page_size - (guest_phys_addr & (page_size - 1));
        size = RTE_MIN(size, reg_size);
 
-       add_one_guest_page(dev, guest_phys_addr, host_phys_addr, size);
+       if (add_one_guest_page(dev, guest_phys_addr, host_phys_addr, size) < 0)
+               return -1;
+
        host_user_addr  += size;
        guest_phys_addr += size;
        reg_size -= size;
@@ -576,12 +780,16 @@ add_guest_pages(struct virtio_net *dev, struct rte_vhost_mem_region *reg,
                size = RTE_MIN(reg_size, page_size);
                host_phys_addr = rte_mem_virt2iova((void *)(uintptr_t)
                                                  host_user_addr);
-               add_one_guest_page(dev, guest_phys_addr, host_phys_addr, size);
+               if (add_one_guest_page(dev, guest_phys_addr, host_phys_addr,
+                               size) < 0)
+                       return -1;
 
                host_user_addr  += size;
                guest_phys_addr += size;
                reg_size -= size;
        }
+
+       return 0;
 }
 
 #ifdef RTE_LIBRTE_VHOST_DEBUG
@@ -635,25 +843,34 @@ vhost_memory_changed(struct VhostUserMemory *new,
 }
 
 static int
-vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
+vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd)
 {
-       struct VhostUserMemory memory = pmsg->payload.memory;
+       struct virtio_net *dev = *pdev;
+       struct VhostUserMemory *memory = &msg->payload.memory;
        struct rte_vhost_mem_region *reg;
        void *mmap_addr;
        uint64_t mmap_size;
        uint64_t mmap_offset;
        uint64_t alignment;
        uint32_t i;
+       int populate;
        int fd;
 
-       if (dev->mem && !vhost_memory_changed(&memory, dev->mem)) {
+       if (memory->nregions > VHOST_MEMORY_MAX_NREGIONS) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "too many memory regions (%u)\n", memory->nregions);
+               return VH_RESULT_ERR;
+       }
+
+       if (dev->mem && !vhost_memory_changed(memory, dev->mem)) {
                RTE_LOG(INFO, VHOST_CONFIG,
                        "(%d) memory regions not changed\n", dev->vid);
 
-               for (i = 0; i < memory.nregions; i++)
-                       close(pmsg->fds[i]);
+               for (i = 0; i < memory->nregions; i++)
+                       close(msg->fds[i]);
 
-               return 0;
+               return VH_RESULT_OK;
        }
 
        if (dev->mem) {
@@ -662,6 +879,11 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
                dev->mem = NULL;
        }
 
+       /* Flush IOTLB cache as previous HVAs are now invalid */
+       if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
+               for (i = 0; i < dev->nr_vring; i++)
+                       vhost_user_iotlb_flush_all(dev->virtqueue[i]);
+
        dev->nr_guest_pages = 0;
        if (!dev->guest_pages) {
                dev->max_guest_pages = 8;
@@ -672,31 +894,41 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
                                "(%d) failed to allocate memory "
                                "for dev->guest_pages\n",
                                dev->vid);
-                       return -1;
+                       return VH_RESULT_ERR;
                }
        }
 
        dev->mem = rte_zmalloc("vhost-mem-table", sizeof(struct rte_vhost_memory) +
-               sizeof(struct rte_vhost_mem_region) * memory.nregions, 0);
+               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",
                        dev->vid);
-               return -1;
+               return VH_RESULT_ERR;
        }
-       dev->mem->nregions = memory.nregions;
+       dev->mem->nregions = memory->nregions;
 
-       for (i = 0; i < memory.nregions; i++) {
-               fd  = pmsg->fds[i];
+       for (i = 0; i < memory->nregions; i++) {
+               fd  = msg->fds[i];
                reg = &dev->mem->regions[i];
 
-               reg->guest_phys_addr = memory.regions[i].guest_phys_addr;
-               reg->guest_user_addr = memory.regions[i].userspace_addr;
-               reg->size            = memory.regions[i].memory_size;
+               reg->guest_phys_addr = memory->regions[i].guest_phys_addr;
+               reg->guest_user_addr = memory->regions[i].userspace_addr;
+               reg->size            = memory->regions[i].memory_size;
                reg->fd              = fd;
 
-               mmap_offset = memory.regions[i].mmap_offset;
-               mmap_size   = reg->size + mmap_offset;
+               mmap_offset = memory->regions[i].mmap_offset;
+
+               /* Check for memory_size + mmap_offset overflow */
+               if (mmap_offset >= -reg->size) {
+                       RTE_LOG(ERR, VHOST_CONFIG,
+                               "mmap_offset (%#"PRIx64") and memory_size "
+                               "(%#"PRIx64") overflow\n",
+                               mmap_offset, reg->size);
+                       goto err_mmap;
+               }
+
+               mmap_size = reg->size + mmap_offset;
 
                /* mmap() without flag of MAP_ANONYMOUS, should be called
                 * with length argument aligned with hugepagesz at older
@@ -714,8 +946,9 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
                }
                mmap_size = RTE_ALIGN_CEIL(mmap_size, alignment);
 
+               populate = (dev->dequeue_zero_copy) ? MAP_POPULATE : 0;
                mmap_addr = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE,
-                                MAP_SHARED | MAP_POPULATE, fd, 0);
+                                MAP_SHARED | populate, fd, 0);
 
                if (mmap_addr == MAP_FAILED) {
                        RTE_LOG(ERR, VHOST_CONFIG,
@@ -729,7 +962,12 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
                                      mmap_offset;
 
                if (dev->dequeue_zero_copy)
-                       add_guest_pages(dev, reg, alignment);
+                       if (add_guest_pages(dev, reg, alignment) < 0) {
+                               RTE_LOG(ERR, VHOST_CONFIG,
+                                       "adding guest pages to region %u failed.\n",
+                                       i);
+                               goto err_mmap;
+                       }
 
                RTE_LOG(INFO, VHOST_CONFIG,
                        "guest memory region %u, size: 0x%" PRIx64 "\n"
@@ -748,23 +986,118 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
                        mmap_size,
                        alignment,
                        mmap_offset);
+
+               if (dev->postcopy_listening) {
+                       /*
+                        * We haven't a better way right now than sharing
+                        * DPDK's virtual address with Qemu, so that Qemu can
+                        * retrieve the region offset when handling userfaults.
+                        */
+                       memory->regions[i].userspace_addr =
+                               reg->host_user_addr;
+               }
+       }
+       if (dev->postcopy_listening) {
+               /* Send the addresses back to qemu */
+               msg->fd_num = 0;
+               send_vhost_reply(main_fd, msg);
+
+               /* Wait for qemu to acknolwedge it's got the addresses
+                * we've got to wait before we're allowed to generate faults.
+                */
+               VhostUserMsg ack_msg;
+               if (read_vhost_message(main_fd, &ack_msg) <= 0) {
+                       RTE_LOG(ERR, VHOST_CONFIG,
+                               "Failed to read qemu ack on postcopy set-mem-table\n");
+                       goto err_mmap;
+               }
+               if (ack_msg.request.master != VHOST_USER_SET_MEM_TABLE) {
+                       RTE_LOG(ERR, VHOST_CONFIG,
+                               "Bad qemu ack on postcopy set-mem-table (%d)\n",
+                               ack_msg.request.master);
+                       goto err_mmap;
+               }
+
+               /* Now userfault register and we can use the memory */
+               for (i = 0; i < memory->nregions; i++) {
+#ifdef RTE_LIBRTE_VHOST_POSTCOPY
+                       reg = &dev->mem->regions[i];
+                       struct uffdio_register reg_struct;
+
+                       /*
+                        * Let's register all the mmap'ed area to ensure
+                        * alignment on page boundary.
+                        */
+                       reg_struct.range.start =
+                               (uint64_t)(uintptr_t)reg->mmap_addr;
+                       reg_struct.range.len = reg->mmap_size;
+                       reg_struct.mode = UFFDIO_REGISTER_MODE_MISSING;
+
+                       if (ioctl(dev->postcopy_ufd, UFFDIO_REGISTER,
+                                               &reg_struct)) {
+                               RTE_LOG(ERR, VHOST_CONFIG,
+                                       "Failed to register ufd for region %d: (ufd = %d) %s\n",
+                                       i, dev->postcopy_ufd,
+                                       strerror(errno));
+                               goto err_mmap;
+                       }
+                       RTE_LOG(INFO, VHOST_CONFIG,
+                               "\t userfaultfd registered for range : %llx - %llx\n",
+                               reg_struct.range.start,
+                               reg_struct.range.start +
+                               reg_struct.range.len - 1);
+#else
+                       goto err_mmap;
+#endif
+               }
+       }
+
+       for (i = 0; i < dev->nr_vring; i++) {
+               struct vhost_virtqueue *vq = dev->virtqueue[i];
+
+               if (vq->desc || vq->avail || vq->used) {
+                       /*
+                        * If the memory table got updated, the ring addresses
+                        * need to be translated again as virtual addresses have
+                        * changed.
+                        */
+                       vring_invalidate(dev, vq);
+
+                       dev = translate_ring_addresses(dev, i);
+                       if (!dev) {
+                               dev = *pdev;
+                               goto err_mmap;
+                       }
+
+                       *pdev = dev;
+               }
        }
 
        dump_guest_pages(dev);
 
-       return 0;
+       return VH_RESULT_OK;
 
 err_mmap:
        free_mem_region(dev);
        rte_free(dev->mem);
        dev->mem = NULL;
-       return -1;
+       return VH_RESULT_ERR;
 }
 
-static int
-vq_is_ready(struct vhost_virtqueue *vq)
+static bool
+vq_is_ready(struct virtio_net *dev, struct vhost_virtqueue *vq)
 {
-       return vq && vq->desc && vq->avail && vq->used &&
+       bool rings_ok;
+
+       if (!vq)
+               return false;
+
+       if (vq_is_packed(dev))
+               rings_ok = !!vq->desc_packed;
+       else
+               rings_ok = vq->desc && vq->avail && vq->used;
+
+       return rings_ok &&
               vq->kickfd != VIRTIO_UNINITIALIZED_EVENTFD &&
               vq->callfd != VIRTIO_UNINITIALIZED_EVENTFD;
 }
@@ -781,7 +1114,7 @@ virtio_is_ready(struct virtio_net *dev)
        for (i = 0; i < dev->nr_vring; i++) {
                vq = dev->virtqueue[i];
 
-               if (!vq_is_ready(vq))
+               if (!vq_is_ready(dev, vq))
                        return 0;
        }
 
@@ -790,17 +1123,19 @@ virtio_is_ready(struct virtio_net *dev)
        return 1;
 }
 
-static void
-vhost_user_set_vring_call(struct virtio_net *dev, struct VhostUserMsg *pmsg)
+static int
+vhost_user_set_vring_call(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        struct vhost_vring_file file;
        struct vhost_virtqueue *vq;
 
-       file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
-       if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
+       file.index = msg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
+       if (msg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
                file.fd = VIRTIO_INVALID_EVENTFD;
        else
-               file.fd = pmsg->fds[0];
+               file.fd = msg->fds[0];
        RTE_LOG(INFO, VHOST_CONFIG,
                "vring call idx:%d file:%d\n", file.index, file.fd);
 
@@ -809,27 +1144,41 @@ vhost_user_set_vring_call(struct virtio_net *dev, struct VhostUserMsg *pmsg)
                close(vq->callfd);
 
        vq->callfd = file.fd;
+
+       return VH_RESULT_OK;
 }
 
-static void
-vhost_user_set_vring_kick(struct virtio_net **pdev, struct VhostUserMsg *pmsg)
+static int vhost_user_set_vring_err(struct virtio_net **pdev __rte_unused,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       if (!(msg->payload.u64 & VHOST_USER_VRING_NOFD_MASK))
+               close(msg->fds[0]);
+       RTE_LOG(INFO, VHOST_CONFIG, "not implemented\n");
+
+       return VH_RESULT_OK;
+}
+
+static int
+vhost_user_set_vring_kick(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
+{
+       struct virtio_net *dev = *pdev;
        struct vhost_vring_file file;
        struct vhost_virtqueue *vq;
-       struct virtio_net *dev = *pdev;
 
-       file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
-       if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
+       file.index = msg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
+       if (msg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
                file.fd = VIRTIO_INVALID_EVENTFD;
        else
-               file.fd = pmsg->fds[0];
+               file.fd = msg->fds[0];
        RTE_LOG(INFO, VHOST_CONFIG,
                "vring kick idx:%d file:%d\n", file.index, file.fd);
 
        /* Interpret ring addresses only when ring is started. */
        dev = translate_ring_addresses(dev, file.index);
        if (!dev)
-               return;
+               return VH_RESULT_ERR;
 
        *pdev = dev;
 
@@ -846,6 +1195,8 @@ vhost_user_set_vring_kick(struct virtio_net **pdev, struct VhostUserMsg *pmsg)
        if (vq->kickfd >= 0)
                close(vq->kickfd);
        vq->kickfd = file.fd;
+
+       return VH_RESULT_OK;
 }
 
 static void
@@ -868,21 +1219,32 @@ free_zmbufs(struct vhost_virtqueue *vq)
  * when virtio is stopped, qemu will send us the GET_VRING_BASE message.
  */
 static int
-vhost_user_get_vring_base(struct virtio_net *dev,
-                         VhostUserMsg *msg)
+vhost_user_get_vring_base(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        struct vhost_virtqueue *vq = dev->virtqueue[msg->payload.state.index];
+       uint64_t val;
 
        /* We have to stop the queue (virtio) if it is running. */
-       if (dev->flags & VIRTIO_DEV_RUNNING) {
-               dev->flags &= ~VIRTIO_DEV_RUNNING;
-               dev->notify_ops->destroy_device(dev->vid);
-       }
+       vhost_destroy_device_notify(dev);
 
        dev->flags &= ~VIRTIO_DEV_READY;
+       dev->flags &= ~VIRTIO_DEV_VDPA_CONFIGURED;
 
-       /* Here we are safe to get the last used index */
-       msg->payload.state.num = vq->last_used_idx;
+       /* Here we are safe to get the indexes */
+       if (vq_is_packed(dev)) {
+               /*
+                * Bit[0:14]: avail index
+                * Bit[15]: avail wrap counter
+                */
+               val = vq->last_avail_idx & 0x7fff;
+               val |= vq->avail_wrap_counter << 15;
+               msg->payload.state.num = val;
+       } else {
+               msg->payload.state.num = vq->last_avail_idx;
+       }
 
        RTE_LOG(INFO, VHOST_CONFIG,
                "vring base idx:%d file:%d\n", msg->payload.state.index,
@@ -897,15 +1259,28 @@ vhost_user_get_vring_base(struct virtio_net *dev,
 
        vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
 
+       if (vq->callfd >= 0)
+               close(vq->callfd);
+
+       vq->callfd = VIRTIO_UNINITIALIZED_EVENTFD;
+
        if (dev->dequeue_zero_copy)
                free_zmbufs(vq);
-       rte_free(vq->shadow_used_ring);
-       vq->shadow_used_ring = NULL;
+       if (vq_is_packed(dev)) {
+               rte_free(vq->shadow_used_packed);
+               vq->shadow_used_packed = NULL;
+       } else {
+               rte_free(vq->shadow_used_split);
+               vq->shadow_used_split = NULL;
+       }
 
        rte_free(vq->batch_copy_elems);
        vq->batch_copy_elems = NULL;
 
-       return 0;
+       msg->size = sizeof(msg->payload.state);
+       msg->fd_num = 0;
+
+       return VH_RESULT_REPLY;
 }
 
 /*
@@ -913,31 +1288,44 @@ vhost_user_get_vring_base(struct virtio_net *dev,
  * enable the virtio queue pair.
  */
 static int
-vhost_user_set_vring_enable(struct virtio_net *dev,
-                           VhostUserMsg *msg)
+vhost_user_set_vring_enable(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        int enable = (int)msg->payload.state.num;
+       int index = (int)msg->payload.state.index;
+       struct rte_vdpa_device *vdpa_dev;
+       int did = -1;
 
        RTE_LOG(INFO, VHOST_CONFIG,
                "set queue enable: %d to qp idx: %d\n",
-               enable, msg->payload.state.index);
+               enable, index);
+
+       did = dev->vdpa_dev_id;
+       vdpa_dev = rte_vdpa_get_device(did);
+       if (vdpa_dev && vdpa_dev->ops->set_vring_state)
+               vdpa_dev->ops->set_vring_state(dev->vid, index, enable);
 
        if (dev->notify_ops->vring_state_changed)
                dev->notify_ops->vring_state_changed(dev->vid,
-                               msg->payload.state.index, enable);
+                               index, enable);
 
-       dev->virtqueue[msg->payload.state.index]->enabled = enable;
+       dev->virtqueue[index]->enabled = enable;
 
-       return 0;
+       return VH_RESULT_OK;
 }
 
-static void
-vhost_user_get_protocol_features(struct virtio_net *dev,
-                                struct VhostUserMsg *msg)
+static int
+vhost_user_get_protocol_features(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
-       uint64_t features, protocol_features = VHOST_USER_PROTOCOL_FEATURES;
+       struct virtio_net *dev = *pdev;
+       uint64_t features, protocol_features;
 
        rte_vhost_driver_get_features(dev->ifname, &features);
+       rte_vhost_driver_get_protocol_features(dev->ifname, &protocol_features);
 
        /*
         * REPLY_ACK protocol feature is only mandatory for now
@@ -950,39 +1338,66 @@ vhost_user_get_protocol_features(struct virtio_net *dev,
 
        msg->payload.u64 = protocol_features;
        msg->size = sizeof(msg->payload.u64);
+       msg->fd_num = 0;
+
+       return VH_RESULT_REPLY;
 }
 
-static void
-vhost_user_set_protocol_features(struct virtio_net *dev,
-                                uint64_t protocol_features)
+static int
+vhost_user_set_protocol_features(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
-       if (protocol_features & ~VHOST_USER_PROTOCOL_FEATURES)
-               return;
+       struct virtio_net *dev = *pdev;
+       uint64_t protocol_features = msg->payload.u64;
+       uint64_t slave_protocol_features = 0;
+
+       rte_vhost_driver_get_protocol_features(dev->ifname,
+                       &slave_protocol_features);
+       if (protocol_features & ~slave_protocol_features) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "(%d) received invalid protocol features.\n",
+                       dev->vid);
+               return VH_RESULT_ERR;
+       }
 
        dev->protocol_features = protocol_features;
+
+       return VH_RESULT_OK;
 }
 
 static int
-vhost_user_set_log_base(struct virtio_net *dev, struct VhostUserMsg *msg)
+vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        int fd = msg->fds[0];
        uint64_t size, off;
        void *addr;
 
        if (fd < 0) {
                RTE_LOG(ERR, VHOST_CONFIG, "invalid log fd: %d\n", fd);
-               return -1;
+               return VH_RESULT_ERR;
        }
 
        if (msg->size != sizeof(VhostUserLog)) {
                RTE_LOG(ERR, VHOST_CONFIG,
                        "invalid log base msg size: %"PRId32" != %d\n",
                        msg->size, (int)sizeof(VhostUserLog));
-               return -1;
+               return VH_RESULT_ERR;
        }
 
        size = msg->payload.log.mmap_size;
        off  = msg->payload.log.mmap_offset;
+
+       /* Don't allow mmap_offset to point outside the mmap region */
+       if (off > size) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "log offset %#"PRIx64" exceeds log size %#"PRIx64"\n",
+                       off, size);
+               return VH_RESULT_ERR;
+       }
+
        RTE_LOG(INFO, VHOST_CONFIG,
                "log mmap size: %"PRId64", offset: %"PRId64"\n",
                size, off);
@@ -991,11 +1406,11 @@ vhost_user_set_log_base(struct virtio_net *dev, struct VhostUserMsg *msg)
         * mmap from 0 to workaround a hugepage mmap bug: mmap will
         * fail when offset is not page size aligned.
         */
-       addr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+       addr = mmap(0, size + off, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
        close(fd);
        if (addr == MAP_FAILED) {
                RTE_LOG(ERR, VHOST_CONFIG, "mmap log base failed!\n");
-               return -1;
+               return VH_RESULT_ERR;
        }
 
        /*
@@ -1009,7 +1424,24 @@ vhost_user_set_log_base(struct virtio_net *dev, struct VhostUserMsg *msg)
        dev->log_base = dev->log_addr + off;
        dev->log_size = size;
 
-       return 0;
+       /*
+        * The spec is not clear about it (yet), but QEMU doesn't expect
+        * any payload in the reply.
+        */
+       msg->size = 0;
+       msg->fd_num = 0;
+
+       return VH_RESULT_REPLY;
+}
+
+static int vhost_user_set_log_fd(struct virtio_net **pdev __rte_unused,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
+{
+       close(msg->fds[0]);
+       RTE_LOG(INFO, VHOST_CONFIG, "not implemented.\n");
+
+       return VH_RESULT_OK;
 }
 
 /*
@@ -1021,9 +1453,13 @@ vhost_user_set_log_base(struct virtio_net *dev, struct VhostUserMsg *msg)
  * a flag 'broadcast_rarp' to let rte_vhost_dequeue_burst() inject it.
  */
 static int
-vhost_user_send_rarp(struct virtio_net *dev, struct VhostUserMsg *msg)
+vhost_user_send_rarp(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        uint8_t *mac = (uint8_t *)&msg->payload.u64;
+       struct rte_vdpa_device *vdpa_dev;
+       int did = -1;
 
        RTE_LOG(DEBUG, VHOST_CONFIG,
                ":: mac: %02x:%02x:%02x:%02x:%02x:%02x\n",
@@ -1039,41 +1475,49 @@ vhost_user_send_rarp(struct virtio_net *dev, struct VhostUserMsg *msg)
         */
        rte_smp_wmb();
        rte_atomic16_set(&dev->broadcast_rarp, 1);
+       did = dev->vdpa_dev_id;
+       vdpa_dev = rte_vdpa_get_device(did);
+       if (vdpa_dev && vdpa_dev->ops->migration_done)
+               vdpa_dev->ops->migration_done(dev->vid);
 
-       return 0;
+       return VH_RESULT_OK;
 }
 
 static int
-vhost_user_net_set_mtu(struct virtio_net *dev, struct VhostUserMsg *msg)
+vhost_user_net_set_mtu(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        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;
+               return VH_RESULT_ERR;
        }
 
        dev->mtu = msg->payload.u64;
 
-       return 0;
+       return VH_RESULT_OK;
 }
 
 static int
-vhost_user_set_req_fd(struct virtio_net *dev, struct VhostUserMsg *msg)
+vhost_user_set_req_fd(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
+       struct virtio_net *dev = *pdev;
        int fd = msg->fds[0];
 
        if (fd < 0) {
                RTE_LOG(ERR, VHOST_CONFIG,
                                "Invalid file descriptor for slave channel (%d)\n",
                                fd);
-               return -1;
+               return VH_RESULT_ERR;
        }
 
        dev->slave_req_fd = fd;
 
-       return 0;
+       return VH_RESULT_OK;
 }
 
 static int
@@ -1126,24 +1570,26 @@ is_vring_iotlb_invalidate(struct vhost_virtqueue *vq,
 }
 
 static int
-vhost_user_iotlb_msg(struct virtio_net **pdev, struct VhostUserMsg *msg)
+vhost_user_iotlb_msg(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
 {
        struct virtio_net *dev = *pdev;
        struct vhost_iotlb_msg *imsg = &msg->payload.iotlb;
        uint16_t i;
-       uint64_t vva;
+       uint64_t vva, len;
 
        switch (imsg->type) {
        case VHOST_IOTLB_UPDATE:
-               vva = qva_to_vva(dev, imsg->uaddr);
+               len = imsg->size;
+               vva = qva_to_vva(dev, imsg->uaddr, &len);
                if (!vva)
-                       return -1;
+                       return VH_RESULT_ERR;
 
                for (i = 0; i < dev->nr_vring; i++) {
                        struct vhost_virtqueue *vq = dev->virtqueue[i];
 
                        vhost_user_iotlb_cache_insert(vq, imsg->iova, vva,
-                                       imsg->size, imsg->perm);
+                                       len, imsg->perm);
 
                        if (is_vring_iotlb_update(vq, imsg))
                                *pdev = dev = translate_ring_addresses(dev, i);
@@ -1163,12 +1609,118 @@ vhost_user_iotlb_msg(struct virtio_net **pdev, struct VhostUserMsg *msg)
        default:
                RTE_LOG(ERR, VHOST_CONFIG, "Invalid IOTLB message type (%d)\n",
                                imsg->type);
-               return -1;
+               return VH_RESULT_ERR;
        }
 
-       return 0;
+       return VH_RESULT_OK;
+}
+
+static int
+vhost_user_set_postcopy_advise(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
+{
+       struct virtio_net *dev = *pdev;
+#ifdef RTE_LIBRTE_VHOST_POSTCOPY
+       struct uffdio_api api_struct;
+
+       dev->postcopy_ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
+
+       if (dev->postcopy_ufd == -1) {
+               RTE_LOG(ERR, VHOST_CONFIG, "Userfaultfd not available: %s\n",
+                       strerror(errno));
+               return VH_RESULT_ERR;
+       }
+       api_struct.api = UFFD_API;
+       api_struct.features = 0;
+       if (ioctl(dev->postcopy_ufd, UFFDIO_API, &api_struct)) {
+               RTE_LOG(ERR, VHOST_CONFIG, "UFFDIO_API ioctl failure: %s\n",
+                       strerror(errno));
+               close(dev->postcopy_ufd);
+               dev->postcopy_ufd = -1;
+               return VH_RESULT_ERR;
+       }
+       msg->fds[0] = dev->postcopy_ufd;
+       msg->fd_num = 1;
+
+       return VH_RESULT_REPLY;
+#else
+       dev->postcopy_ufd = -1;
+       msg->fd_num = 0;
+
+       return VH_RESULT_ERR;
+#endif
+}
+
+static int
+vhost_user_set_postcopy_listen(struct virtio_net **pdev,
+                       struct VhostUserMsg *msg __rte_unused,
+                       int main_fd __rte_unused)
+{
+       struct virtio_net *dev = *pdev;
+
+       if (dev->mem && dev->mem->nregions) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "Regions already registered at postcopy-listen\n");
+               return VH_RESULT_ERR;
+       }
+       dev->postcopy_listening = 1;
+
+       return VH_RESULT_OK;
+}
+
+static int
+vhost_user_postcopy_end(struct virtio_net **pdev, struct VhostUserMsg *msg,
+                       int main_fd __rte_unused)
+{
+       struct virtio_net *dev = *pdev;
+
+       dev->postcopy_listening = 0;
+       if (dev->postcopy_ufd >= 0) {
+               close(dev->postcopy_ufd);
+               dev->postcopy_ufd = -1;
+       }
+
+       msg->payload.u64 = 0;
+       msg->size = sizeof(msg->payload.u64);
+       msg->fd_num = 0;
+
+       return VH_RESULT_REPLY;
 }
 
+typedef int (*vhost_message_handler_t)(struct virtio_net **pdev,
+                                       struct VhostUserMsg *msg,
+                                       int main_fd);
+static vhost_message_handler_t vhost_message_handlers[VHOST_USER_MAX] = {
+       [VHOST_USER_NONE] = NULL,
+       [VHOST_USER_GET_FEATURES] = vhost_user_get_features,
+       [VHOST_USER_SET_FEATURES] = vhost_user_set_features,
+       [VHOST_USER_SET_OWNER] = vhost_user_set_owner,
+       [VHOST_USER_RESET_OWNER] = vhost_user_reset_owner,
+       [VHOST_USER_SET_MEM_TABLE] = vhost_user_set_mem_table,
+       [VHOST_USER_SET_LOG_BASE] = vhost_user_set_log_base,
+       [VHOST_USER_SET_LOG_FD] = vhost_user_set_log_fd,
+       [VHOST_USER_SET_VRING_NUM] = vhost_user_set_vring_num,
+       [VHOST_USER_SET_VRING_ADDR] = vhost_user_set_vring_addr,
+       [VHOST_USER_SET_VRING_BASE] = vhost_user_set_vring_base,
+       [VHOST_USER_GET_VRING_BASE] = vhost_user_get_vring_base,
+       [VHOST_USER_SET_VRING_KICK] = vhost_user_set_vring_kick,
+       [VHOST_USER_SET_VRING_CALL] = vhost_user_set_vring_call,
+       [VHOST_USER_SET_VRING_ERR] = vhost_user_set_vring_err,
+       [VHOST_USER_GET_PROTOCOL_FEATURES] = vhost_user_get_protocol_features,
+       [VHOST_USER_SET_PROTOCOL_FEATURES] = vhost_user_set_protocol_features,
+       [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,
+       [VHOST_USER_SET_SLAVE_REQ_FD] = vhost_user_set_req_fd,
+       [VHOST_USER_IOTLB_MSG] = vhost_user_iotlb_msg,
+       [VHOST_USER_POSTCOPY_ADVISE] = vhost_user_set_postcopy_advise,
+       [VHOST_USER_POSTCOPY_LISTEN] = vhost_user_set_postcopy_listen,
+       [VHOST_USER_POSTCOPY_END] = vhost_user_postcopy_end,
+};
+
+
 /* return bytes# of read on success or negative val on failure. */
 static int
 read_vhost_message(int sockfd, struct VhostUserMsg *msg)
@@ -1176,11 +1728,11 @@ read_vhost_message(int sockfd, struct VhostUserMsg *msg)
        int ret;
 
        ret = read_fd_message(sockfd, (char *)msg, VHOST_USER_HDR_SIZE,
-               msg->fds, VHOST_MEMORY_MAX_NREGIONS);
+               msg->fds, VHOST_MEMORY_MAX_NREGIONS, &msg->fd_num);
        if (ret <= 0)
                return ret;
 
-       if (msg && msg->size) {
+       if (msg->size) {
                if (msg->size > sizeof(msg->payload)) {
                        RTE_LOG(ERR, VHOST_CONFIG,
                                "invalid msg size: %d\n", msg->size);
@@ -1206,7 +1758,7 @@ send_vhost_message(int sockfd, struct VhostUserMsg *msg)
                return 0;
 
        return send_fd_message(sockfd, (char *)msg,
-               VHOST_USER_HDR_SIZE + msg->size, NULL, 0);
+               VHOST_USER_HDR_SIZE + msg->size, msg->fds, msg->fd_num);
 }
 
 static int
@@ -1223,11 +1775,27 @@ send_vhost_reply(int sockfd, struct VhostUserMsg *msg)
        return send_vhost_message(sockfd, msg);
 }
 
+static int
+send_vhost_slave_message(struct virtio_net *dev, struct VhostUserMsg *msg)
+{
+       int ret;
+
+       if (msg->flags & VHOST_USER_NEED_REPLY)
+               rte_spinlock_lock(&dev->slave_req_lock);
+
+       ret = send_vhost_message(dev->slave_req_fd, msg);
+       if (ret < 0 && (msg->flags & VHOST_USER_NEED_REPLY))
+               rte_spinlock_unlock(&dev->slave_req_lock);
+
+       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)
+vhost_user_check_and_alloc_queue_pair(struct virtio_net *dev,
+                       struct VhostUserMsg *msg)
 {
        uint16_t vring_idx;
 
@@ -1300,8 +1868,12 @@ vhost_user_msg_handler(int vid, int fd)
 {
        struct virtio_net *dev;
        struct VhostUserMsg msg;
+       struct rte_vdpa_device *vdpa_dev;
+       int did = -1;
        int ret;
        int unlock_required = 0;
+       uint32_t skip_master = 0;
+       int request;
 
        dev = get_device(vid);
        if (dev == NULL)
@@ -1379,116 +1951,76 @@ vhost_user_msg_handler(int vid, int fd)
 
        }
 
-       switch (msg.request.master) {
-       case VHOST_USER_GET_FEATURES:
-               msg.payload.u64 = vhost_user_get_features(dev);
-               msg.size = sizeof(msg.payload.u64);
-               send_vhost_reply(fd, &msg);
-               break;
-       case VHOST_USER_SET_FEATURES:
-               ret = vhost_user_set_features(dev, msg.payload.u64);
-               if (ret)
-                       return -1;
-               break;
-
-       case VHOST_USER_GET_PROTOCOL_FEATURES:
-               vhost_user_get_protocol_features(dev, &msg);
-               send_vhost_reply(fd, &msg);
-               break;
-       case VHOST_USER_SET_PROTOCOL_FEATURES:
-               vhost_user_set_protocol_features(dev, msg.payload.u64);
-               break;
-
-       case VHOST_USER_SET_OWNER:
-               vhost_user_set_owner();
-               break;
-       case VHOST_USER_RESET_OWNER:
-               vhost_user_reset_owner(dev);
-               break;
-
-       case VHOST_USER_SET_MEM_TABLE:
-               ret = vhost_user_set_mem_table(dev, &msg);
-               break;
-
-       case VHOST_USER_SET_LOG_BASE:
-               vhost_user_set_log_base(dev, &msg);
-
-               /* it needs a reply */
-               msg.size = sizeof(msg.payload.u64);
-               send_vhost_reply(fd, &msg);
-               break;
-       case VHOST_USER_SET_LOG_FD:
-               close(msg.fds[0]);
-               RTE_LOG(INFO, VHOST_CONFIG, "not implemented.\n");
-               break;
-
-       case VHOST_USER_SET_VRING_NUM:
-               vhost_user_set_vring_num(dev, &msg);
-               break;
-       case VHOST_USER_SET_VRING_ADDR:
-               vhost_user_set_vring_addr(&dev, &msg);
-               break;
-       case VHOST_USER_SET_VRING_BASE:
-               vhost_user_set_vring_base(dev, &msg);
-               break;
-
-       case VHOST_USER_GET_VRING_BASE:
-               vhost_user_get_vring_base(dev, &msg);
-               msg.size = sizeof(msg.payload.state);
-               send_vhost_reply(fd, &msg);
-               break;
-
-       case VHOST_USER_SET_VRING_KICK:
-               vhost_user_set_vring_kick(&dev, &msg);
-               break;
-       case VHOST_USER_SET_VRING_CALL:
-               vhost_user_set_vring_call(dev, &msg);
-               break;
-
-       case VHOST_USER_SET_VRING_ERR:
-               if (!(msg.payload.u64 & VHOST_USER_VRING_NOFD_MASK))
-                       close(msg.fds[0]);
-               RTE_LOG(INFO, VHOST_CONFIG, "not implemented\n");
-               break;
-
-       case VHOST_USER_GET_QUEUE_NUM:
-               msg.payload.u64 = VHOST_MAX_QUEUE_PAIRS;
-               msg.size = sizeof(msg.payload.u64);
-               send_vhost_reply(fd, &msg);
-               break;
-
-       case VHOST_USER_SET_VRING_ENABLE:
-               vhost_user_set_vring_enable(dev, &msg);
-               break;
-       case VHOST_USER_SEND_RARP:
-               vhost_user_send_rarp(dev, &msg);
-               break;
-
-       case VHOST_USER_NET_SET_MTU:
-               ret = vhost_user_net_set_mtu(dev, &msg);
-               break;
+       if (dev->extern_ops.pre_msg_handle) {
+               ret = (*dev->extern_ops.pre_msg_handle)(dev->vid,
+                               (void *)&msg, &skip_master);
+               if (ret == VH_RESULT_ERR)
+                       goto skip_to_reply;
+               else if (ret == VH_RESULT_REPLY)
+                       send_vhost_reply(fd, &msg);
 
-       case VHOST_USER_SET_SLAVE_REQ_FD:
-               ret = vhost_user_set_req_fd(dev, &msg);
-               break;
+               if (skip_master)
+                       goto skip_to_post_handle;
+       }
 
-       case VHOST_USER_IOTLB_MSG:
-               ret = vhost_user_iotlb_msg(&dev, &msg);
-               break;
+       request = msg.request.master;
+       if (request > VHOST_USER_NONE && request < VHOST_USER_MAX) {
+               if (!vhost_message_handlers[request])
+                       goto skip_to_post_handle;
+               ret = vhost_message_handlers[request](&dev, &msg, fd);
 
-       default:
-               ret = -1;
-               break;
+               switch (ret) {
+               case VH_RESULT_ERR:
+                       RTE_LOG(ERR, VHOST_CONFIG,
+                               "Processing %s failed.\n",
+                               vhost_message_str[request]);
+                       break;
+               case VH_RESULT_OK:
+                       RTE_LOG(DEBUG, VHOST_CONFIG,
+                               "Processing %s succeeded.\n",
+                               vhost_message_str[request]);
+                       break;
+               case VH_RESULT_REPLY:
+                       RTE_LOG(DEBUG, VHOST_CONFIG,
+                               "Processing %s succeeded and needs reply.\n",
+                               vhost_message_str[request]);
+                       send_vhost_reply(fd, &msg);
+                       break;
+               }
+       } else {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "Requested invalid message type %d.\n", request);
+               ret = VH_RESULT_ERR;
+       }
 
+skip_to_post_handle:
+       if (ret != VH_RESULT_ERR && dev->extern_ops.post_msg_handle) {
+               ret = (*dev->extern_ops.post_msg_handle)(
+                               dev->vid, (void *)&msg);
+               if (ret == VH_RESULT_ERR)
+                       goto skip_to_reply;
+               else if (ret == VH_RESULT_REPLY)
+                       send_vhost_reply(fd, &msg);
        }
 
+skip_to_reply:
        if (unlock_required)
                vhost_user_unlock_all_queue_pairs(dev);
 
+       /*
+        * If the request required a reply that was already sent,
+        * this optional reply-ack won't be sent as the
+        * VHOST_USER_NEED_REPLY was cleared in send_vhost_reply().
+        */
        if (msg.flags & VHOST_USER_NEED_REPLY) {
-               msg.payload.u64 = !!ret;
+               msg.payload.u64 = ret == VH_RESULT_ERR;
                msg.size = sizeof(msg.payload.u64);
+               msg.fd_num = 0;
                send_vhost_reply(fd, &msg);
+       } else if (ret == VH_RESULT_ERR) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "vhost message handling failed.\n");
+               return -1;
        }
 
        if (!(dev->flags & VIRTIO_DEV_RUNNING) && virtio_is_ready(dev)) {
@@ -1505,9 +2037,53 @@ vhost_user_msg_handler(int vid, int fd)
                }
        }
 
+       did = dev->vdpa_dev_id;
+       vdpa_dev = rte_vdpa_get_device(did);
+       if (vdpa_dev && virtio_is_ready(dev) &&
+                       !(dev->flags & VIRTIO_DEV_VDPA_CONFIGURED) &&
+                       msg.request.master == VHOST_USER_SET_VRING_ENABLE) {
+               if (vdpa_dev->ops->dev_conf)
+                       vdpa_dev->ops->dev_conf(dev->vid);
+               dev->flags |= VIRTIO_DEV_VDPA_CONFIGURED;
+               if (vhost_user_host_notifier_ctrl(dev->vid, true) != 0) {
+                       RTE_LOG(INFO, VHOST_CONFIG,
+                               "(%d) software relay is used for vDPA, performance may be low.\n",
+                               dev->vid);
+               }
+       }
+
        return 0;
 }
 
+static int process_slave_message_reply(struct virtio_net *dev,
+                                      const struct VhostUserMsg *msg)
+{
+       struct VhostUserMsg msg_reply;
+       int ret;
+
+       if ((msg->flags & VHOST_USER_NEED_REPLY) == 0)
+               return 0;
+
+       if (read_vhost_message(dev->slave_req_fd, &msg_reply) < 0) {
+               ret = -1;
+               goto out;
+       }
+
+       if (msg_reply.request.slave != msg->request.slave) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "Received unexpected msg type (%u), expected %u\n",
+                       msg_reply.request.slave, msg->request.slave);
+               ret = -1;
+               goto out;
+       }
+
+       ret = msg_reply.payload.u64 ? -1 : 0;
+
+out:
+       rte_spinlock_unlock(&dev->slave_req_lock);
+       return ret;
+}
+
 int
 vhost_user_iotlb_miss(struct virtio_net *dev, uint64_t iova, uint8_t perm)
 {
@@ -1533,3 +2109,99 @@ vhost_user_iotlb_miss(struct virtio_net *dev, uint64_t iova, uint8_t perm)
 
        return 0;
 }
+
+static int vhost_user_slave_set_vring_host_notifier(struct virtio_net *dev,
+                                                   int index, int fd,
+                                                   uint64_t offset,
+                                                   uint64_t size)
+{
+       int ret;
+       struct VhostUserMsg msg = {
+               .request.slave = VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG,
+               .flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY,
+               .size = sizeof(msg.payload.area),
+               .payload.area = {
+                       .u64 = index & VHOST_USER_VRING_IDX_MASK,
+                       .size = size,
+                       .offset = offset,
+               },
+       };
+
+       if (fd < 0)
+               msg.payload.area.u64 |= VHOST_USER_VRING_NOFD_MASK;
+       else {
+               msg.fds[0] = fd;
+               msg.fd_num = 1;
+       }
+
+       ret = send_vhost_slave_message(dev, &msg);
+       if (ret < 0) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "Failed to set host notifier (%d)\n", ret);
+               return ret;
+       }
+
+       return process_slave_message_reply(dev, &msg);
+}
+
+int vhost_user_host_notifier_ctrl(int vid, bool enable)
+{
+       struct virtio_net *dev;
+       struct rte_vdpa_device *vdpa_dev;
+       int vfio_device_fd, did, ret = 0;
+       uint64_t offset, size;
+       unsigned int i;
+
+       dev = get_device(vid);
+       if (!dev)
+               return -ENODEV;
+
+       did = dev->vdpa_dev_id;
+       if (did < 0)
+               return -EINVAL;
+
+       if (!(dev->features & (1ULL << VIRTIO_F_VERSION_1)) ||
+           !(dev->features & (1ULL << VHOST_USER_F_PROTOCOL_FEATURES)) ||
+           !(dev->protocol_features &
+                       (1ULL << VHOST_USER_PROTOCOL_F_SLAVE_REQ)) ||
+           !(dev->protocol_features &
+                       (1ULL << VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD)) ||
+           !(dev->protocol_features &
+                       (1ULL << VHOST_USER_PROTOCOL_F_HOST_NOTIFIER)))
+               return -ENOTSUP;
+
+       vdpa_dev = rte_vdpa_get_device(did);
+       if (!vdpa_dev)
+               return -ENODEV;
+
+       RTE_FUNC_PTR_OR_ERR_RET(vdpa_dev->ops->get_vfio_device_fd, -ENOTSUP);
+       RTE_FUNC_PTR_OR_ERR_RET(vdpa_dev->ops->get_notify_area, -ENOTSUP);
+
+       vfio_device_fd = vdpa_dev->ops->get_vfio_device_fd(vid);
+       if (vfio_device_fd < 0)
+               return -ENOTSUP;
+
+       if (enable) {
+               for (i = 0; i < dev->nr_vring; i++) {
+                       if (vdpa_dev->ops->get_notify_area(vid, i, &offset,
+                                       &size) < 0) {
+                               ret = -ENOTSUP;
+                               goto disable;
+                       }
+
+                       if (vhost_user_slave_set_vring_host_notifier(dev, i,
+                                       vfio_device_fd, offset, size) < 0) {
+                               ret = -EFAULT;
+                               goto disable;
+                       }
+               }
+       } else {
+disable:
+               for (i = 0; i < dev->nr_vring; i++) {
+                       vhost_user_slave_set_vring_host_notifier(dev, i, -1,
+                                       0, 0);
+               }
+       }
+
+       return ret;
+}