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-rw-r--r--lib/librte_vhost/virtio-net.c772
1 files changed, 772 insertions, 0 deletions
diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
new file mode 100644
index 00000000..d870ad97
--- /dev/null
+++ b/lib/librte_vhost/virtio-net.c
@@ -0,0 +1,772 @@
+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#ifdef RTE_LIBRTE_VHOST_NUMA
+#include <numaif.h>
+#endif
+
+#include <sys/socket.h>
+
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+#include <rte_memory.h>
+#include <rte_malloc.h>
+#include <rte_virtio_net.h>
+
+#include "vhost-net.h"
+#include "virtio-net.h"
+
+#define MAX_VHOST_DEVICE 1024
+static struct virtio_net *vhost_devices[MAX_VHOST_DEVICE];
+
+/* device ops to add/remove device to/from data core. */
+struct virtio_net_device_ops const *notify_ops;
+
+#define VHOST_USER_F_PROTOCOL_FEATURES 30
+
+/* Features supported by this lib. */
+#define VHOST_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
+ (1ULL << VIRTIO_NET_F_CTRL_VQ) | \
+ (1ULL << VIRTIO_NET_F_CTRL_RX) | \
+ (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE) | \
+ (VHOST_SUPPORTS_MQ) | \
+ (1ULL << VIRTIO_F_VERSION_1) | \
+ (1ULL << VHOST_F_LOG_ALL) | \
+ (1ULL << VHOST_USER_F_PROTOCOL_FEATURES) | \
+ (1ULL << VIRTIO_NET_F_HOST_TSO4) | \
+ (1ULL << VIRTIO_NET_F_HOST_TSO6) | \
+ (1ULL << VIRTIO_NET_F_CSUM) | \
+ (1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
+ (1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
+ (1ULL << VIRTIO_NET_F_GUEST_TSO6))
+
+static uint64_t VHOST_FEATURES = VHOST_SUPPORTED_FEATURES;
+
+
+/*
+ * Converts QEMU virtual address to Vhost virtual address. This function is
+ * used to convert the ring addresses to our address space.
+ */
+static uint64_t
+qva_to_vva(struct virtio_net *dev, uint64_t qemu_va)
+{
+ struct virtio_memory_regions *region;
+ uint64_t vhost_va = 0;
+ uint32_t regionidx = 0;
+
+ /* Find the region where the address lives. */
+ for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+ region = &dev->mem->regions[regionidx];
+ if ((qemu_va >= region->userspace_address) &&
+ (qemu_va <= region->userspace_address +
+ region->memory_size)) {
+ vhost_va = qemu_va + region->guest_phys_address +
+ region->address_offset -
+ region->userspace_address;
+ break;
+ }
+ }
+ return vhost_va;
+}
+
+
+struct virtio_net *
+get_device(struct vhost_device_ctx ctx)
+{
+ struct virtio_net *dev = vhost_devices[ctx.fh];
+
+ if (unlikely(!dev)) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "(%"PRIu64") device not found.\n", ctx.fh);
+ }
+
+ return dev;
+}
+
+static void
+cleanup_vq(struct vhost_virtqueue *vq, int destroy)
+{
+ if ((vq->callfd >= 0) && (destroy != 0))
+ close(vq->callfd);
+ if (vq->kickfd >= 0)
+ close(vq->kickfd);
+}
+
+/*
+ * Unmap any memory, close any file descriptors and
+ * free any memory owned by a device.
+ */
+static void
+cleanup_device(struct virtio_net *dev, int destroy)
+{
+ uint32_t i;
+
+ vhost_backend_cleanup(dev);
+
+ for (i = 0; i < dev->virt_qp_nb; i++) {
+ cleanup_vq(dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_RXQ], destroy);
+ cleanup_vq(dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_TXQ], destroy);
+ }
+}
+
+/*
+ * Release virtqueues and device memory.
+ */
+static void
+free_device(struct virtio_net *dev)
+{
+ uint32_t i;
+
+ for (i = 0; i < dev->virt_qp_nb; i++)
+ rte_free(dev->virtqueue[i * VIRTIO_QNUM]);
+
+ rte_free(dev);
+}
+
+static void
+init_vring_queue(struct vhost_virtqueue *vq, int qp_idx)
+{
+ memset(vq, 0, sizeof(struct vhost_virtqueue));
+
+ vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
+ vq->callfd = VIRTIO_UNINITIALIZED_EVENTFD;
+
+ /* Backends are set to -1 indicating an inactive device. */
+ vq->backend = -1;
+
+ /* always set the default vq pair to enabled */
+ if (qp_idx == 0)
+ vq->enabled = 1;
+}
+
+static void
+init_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
+{
+ uint32_t base_idx = qp_idx * VIRTIO_QNUM;
+
+ init_vring_queue(dev->virtqueue[base_idx + VIRTIO_RXQ], qp_idx);
+ init_vring_queue(dev->virtqueue[base_idx + VIRTIO_TXQ], qp_idx);
+}
+
+static void
+reset_vring_queue(struct vhost_virtqueue *vq, int qp_idx)
+{
+ int callfd;
+
+ callfd = vq->callfd;
+ init_vring_queue(vq, qp_idx);
+ vq->callfd = callfd;
+}
+
+static void
+reset_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
+{
+ uint32_t base_idx = qp_idx * VIRTIO_QNUM;
+
+ reset_vring_queue(dev->virtqueue[base_idx + VIRTIO_RXQ], qp_idx);
+ reset_vring_queue(dev->virtqueue[base_idx + VIRTIO_TXQ], qp_idx);
+}
+
+static int
+alloc_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
+{
+ struct vhost_virtqueue *virtqueue = NULL;
+ uint32_t virt_rx_q_idx = qp_idx * VIRTIO_QNUM + VIRTIO_RXQ;
+ uint32_t virt_tx_q_idx = qp_idx * VIRTIO_QNUM + VIRTIO_TXQ;
+
+ virtqueue = rte_malloc(NULL,
+ sizeof(struct vhost_virtqueue) * VIRTIO_QNUM, 0);
+ if (virtqueue == NULL) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Failed to allocate memory for virt qp:%d.\n", qp_idx);
+ return -1;
+ }
+
+ dev->virtqueue[virt_rx_q_idx] = virtqueue;
+ dev->virtqueue[virt_tx_q_idx] = virtqueue + VIRTIO_TXQ;
+
+ init_vring_queue_pair(dev, qp_idx);
+
+ dev->virt_qp_nb += 1;
+
+ return 0;
+}
+
+/*
+ * Reset some variables in device structure, while keeping few
+ * others untouched, such as device_fh, ifname, virt_qp_nb: they
+ * should be same unless the device is removed.
+ */
+static void
+reset_device(struct virtio_net *dev)
+{
+ uint32_t i;
+
+ dev->features = 0;
+ dev->protocol_features = 0;
+ dev->flags = 0;
+
+ for (i = 0; i < dev->virt_qp_nb; i++)
+ reset_vring_queue_pair(dev, i);
+}
+
+/*
+ * Function is called from the CUSE open function. The device structure is
+ * initialised and a new entry is added to the device configuration linked
+ * list.
+ */
+int
+vhost_new_device(struct vhost_device_ctx ctx)
+{
+ struct virtio_net *dev;
+ int i;
+
+ dev = rte_zmalloc(NULL, sizeof(struct virtio_net), 0);
+ if (dev == NULL) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "(%"PRIu64") Failed to allocate memory for dev.\n",
+ ctx.fh);
+ return -1;
+ }
+
+ for (i = 0; i < MAX_VHOST_DEVICE; i++) {
+ if (vhost_devices[i] == NULL)
+ break;
+ }
+ if (i == MAX_VHOST_DEVICE) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Failed to find a free slot for new device.\n");
+ return -1;
+ }
+
+ vhost_devices[i] = dev;
+ dev->device_fh = i;
+
+ return i;
+}
+
+/*
+ * Function is called from the CUSE release function. This function will
+ * cleanup the device and remove it from device configuration linked list.
+ */
+void
+vhost_destroy_device(struct vhost_device_ctx ctx)
+{
+ struct virtio_net *dev = get_device(ctx);
+
+ if (dev == NULL)
+ return;
+
+ if (dev->flags & VIRTIO_DEV_RUNNING)
+ notify_ops->destroy_device(dev);
+
+ cleanup_device(dev, 1);
+ free_device(dev);
+
+ vhost_devices[ctx.fh] = NULL;
+}
+
+void
+vhost_set_ifname(struct vhost_device_ctx ctx,
+ const char *if_name, unsigned int if_len)
+{
+ struct virtio_net *dev;
+ unsigned int len;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return;
+
+ len = if_len > sizeof(dev->ifname) ?
+ sizeof(dev->ifname) : if_len;
+
+ strncpy(dev->ifname, if_name, len);
+}
+
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_OWNER
+ * This function just returns success at the moment unless
+ * the device hasn't been initialised.
+ */
+int
+vhost_set_owner(struct vhost_device_ctx ctx)
+{
+ struct virtio_net *dev;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_RESET_OWNER
+ */
+int
+vhost_reset_owner(struct vhost_device_ctx ctx)
+{
+ struct virtio_net *dev;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ if (dev->flags & VIRTIO_DEV_RUNNING)
+ notify_ops->destroy_device(dev);
+
+ cleanup_device(dev, 0);
+ reset_device(dev);
+ return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_GET_FEATURES
+ * The features that we support are requested.
+ */
+int
+vhost_get_features(struct vhost_device_ctx ctx, uint64_t *pu)
+{
+ struct virtio_net *dev;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ /* Send our supported features. */
+ *pu = VHOST_FEATURES;
+ return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_FEATURES
+ * We receive the negotiated features supported by us and the virtio device.
+ */
+int
+vhost_set_features(struct vhost_device_ctx ctx, uint64_t *pu)
+{
+ struct virtio_net *dev;
+ uint16_t vhost_hlen;
+ uint16_t i;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+ if (*pu & ~VHOST_FEATURES)
+ return -1;
+
+ dev->features = *pu;
+ if (dev->features &
+ ((1 << VIRTIO_NET_F_MRG_RXBUF) | (1ULL << VIRTIO_F_VERSION_1))) {
+ vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+ } else {
+ vhost_hlen = sizeof(struct virtio_net_hdr);
+ }
+ LOG_DEBUG(VHOST_CONFIG,
+ "(%"PRIu64") Mergeable RX buffers %s, virtio 1 %s\n",
+ dev->device_fh,
+ (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? "on" : "off",
+ (dev->features & (1ULL << VIRTIO_F_VERSION_1)) ? "on" : "off");
+
+ for (i = 0; i < dev->virt_qp_nb; i++) {
+ uint16_t base_idx = i * VIRTIO_QNUM;
+
+ dev->virtqueue[base_idx + VIRTIO_RXQ]->vhost_hlen = vhost_hlen;
+ dev->virtqueue[base_idx + VIRTIO_TXQ]->vhost_hlen = vhost_hlen;
+ }
+
+ return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_NUM
+ * The virtio device sends us the size of the descriptor ring.
+ */
+int
+vhost_set_vring_num(struct vhost_device_ctx ctx,
+ struct vhost_vring_state *state)
+{
+ struct virtio_net *dev;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ /* State->index refers to the queue index. The txq is 1, rxq is 0. */
+ dev->virtqueue[state->index]->size = state->num;
+
+ return 0;
+}
+
+/*
+ * Reallocate virtio_dev and vhost_virtqueue data structure to make them on the
+ * same numa node as the memory of vring descriptor.
+ */
+#ifdef RTE_LIBRTE_VHOST_NUMA
+static struct virtio_net*
+numa_realloc(struct virtio_net *dev, int index)
+{
+ int oldnode, newnode;
+ struct virtio_net *old_dev;
+ struct vhost_virtqueue *old_vq, *vq;
+ int ret;
+
+ /*
+ * vq is allocated on pairs, we should try to do realloc
+ * on first queue of one queue pair only.
+ */
+ if (index % VIRTIO_QNUM != 0)
+ return dev;
+
+ old_dev = dev;
+ vq = old_vq = dev->virtqueue[index];
+
+ ret = get_mempolicy(&newnode, NULL, 0, old_vq->desc,
+ MPOL_F_NODE | MPOL_F_ADDR);
+
+ /* check if we need to reallocate vq */
+ ret |= get_mempolicy(&oldnode, NULL, 0, old_vq,
+ MPOL_F_NODE | MPOL_F_ADDR);
+ if (ret) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Unable to get vq numa information.\n");
+ return dev;
+ }
+ if (oldnode != newnode) {
+ RTE_LOG(INFO, VHOST_CONFIG,
+ "reallocate vq from %d to %d node\n", oldnode, newnode);
+ vq = rte_malloc_socket(NULL, sizeof(*vq) * VIRTIO_QNUM, 0,
+ newnode);
+ if (!vq)
+ return dev;
+
+ memcpy(vq, old_vq, sizeof(*vq) * VIRTIO_QNUM);
+ rte_free(old_vq);
+ }
+
+ /* check if we need to reallocate dev */
+ ret = get_mempolicy(&oldnode, NULL, 0, old_dev,
+ MPOL_F_NODE | MPOL_F_ADDR);
+ if (ret) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Unable to get dev numa information.\n");
+ goto out;
+ }
+ if (oldnode != newnode) {
+ RTE_LOG(INFO, VHOST_CONFIG,
+ "reallocate dev from %d to %d node\n",
+ oldnode, newnode);
+ dev = rte_malloc_socket(NULL, sizeof(*dev), 0, newnode);
+ if (!dev) {
+ dev = old_dev;
+ goto out;
+ }
+
+ memcpy(dev, old_dev, sizeof(*dev));
+ rte_free(old_dev);
+ }
+
+out:
+ dev->virtqueue[index] = vq;
+ dev->virtqueue[index + 1] = vq + 1;
+ vhost_devices[dev->device_fh] = dev;
+
+ return dev;
+}
+#else
+static struct virtio_net*
+numa_realloc(struct virtio_net *dev, int index __rte_unused)
+{
+ return dev;
+}
+#endif
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_ADDR
+ * The virtio device sends us the desc, used and avail ring addresses.
+ * This function then converts these to our address space.
+ */
+int
+vhost_set_vring_addr(struct vhost_device_ctx ctx, struct vhost_vring_addr *addr)
+{
+ struct virtio_net *dev;
+ struct vhost_virtqueue *vq;
+
+ dev = get_device(ctx);
+ if ((dev == NULL) || (dev->mem == NULL))
+ return -1;
+
+ /* addr->index refers to the queue index. The txq 1, rxq is 0. */
+ vq = dev->virtqueue[addr->index];
+
+ /* The addresses are converted from QEMU virtual to Vhost virtual. */
+ vq->desc = (struct vring_desc *)(uintptr_t)qva_to_vva(dev,
+ addr->desc_user_addr);
+ if (vq->desc == 0) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "(%"PRIu64") Failed to find desc ring address.\n",
+ dev->device_fh);
+ return -1;
+ }
+
+ dev = numa_realloc(dev, addr->index);
+ vq = dev->virtqueue[addr->index];
+
+ vq->avail = (struct vring_avail *)(uintptr_t)qva_to_vva(dev,
+ addr->avail_user_addr);
+ if (vq->avail == 0) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "(%"PRIu64") Failed to find avail ring address.\n",
+ dev->device_fh);
+ return -1;
+ }
+
+ vq->used = (struct vring_used *)(uintptr_t)qva_to_vva(dev,
+ addr->used_user_addr);
+ if (vq->used == 0) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "(%"PRIu64") Failed to find used ring address.\n",
+ dev->device_fh);
+ return -1;
+ }
+
+ vq->log_guest_addr = addr->log_guest_addr;
+
+ LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address desc: %p\n",
+ dev->device_fh, vq->desc);
+ LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address avail: %p\n",
+ dev->device_fh, vq->avail);
+ LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address used: %p\n",
+ dev->device_fh, vq->used);
+ LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") log_guest_addr: %"PRIx64"\n",
+ dev->device_fh, vq->log_guest_addr);
+
+ return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_BASE
+ * The virtio device sends us the available ring last used index.
+ */
+int
+vhost_set_vring_base(struct vhost_device_ctx ctx,
+ struct vhost_vring_state *state)
+{
+ struct virtio_net *dev;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ /* State->index refers to the queue index. The txq is 1, rxq is 0. */
+ dev->virtqueue[state->index]->last_used_idx = state->num;
+ dev->virtqueue[state->index]->last_used_idx_res = state->num;
+
+ return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_GET_VRING_BASE
+ * We send the virtio device our available ring last used index.
+ */
+int
+vhost_get_vring_base(struct vhost_device_ctx ctx, uint32_t index,
+ struct vhost_vring_state *state)
+{
+ struct virtio_net *dev;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ state->index = index;
+ /* State->index refers to the queue index. The txq is 1, rxq is 0. */
+ state->num = dev->virtqueue[state->index]->last_used_idx;
+
+ return 0;
+}
+
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_CALL
+ * The virtio device sends an eventfd to interrupt the guest. This fd gets
+ * copied into our process space.
+ */
+int
+vhost_set_vring_call(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+ struct virtio_net *dev;
+ struct vhost_virtqueue *vq;
+ uint32_t cur_qp_idx = file->index / VIRTIO_QNUM;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ /*
+ * FIXME: VHOST_SET_VRING_CALL is the first per-vring message
+ * we get, so we do vring queue pair allocation here.
+ */
+ if (cur_qp_idx + 1 > dev->virt_qp_nb) {
+ if (alloc_vring_queue_pair(dev, cur_qp_idx) < 0)
+ return -1;
+ }
+
+ /* file->index refers to the queue index. The txq is 1, rxq is 0. */
+ vq = dev->virtqueue[file->index];
+ assert(vq != NULL);
+
+ if (vq->callfd >= 0)
+ close(vq->callfd);
+
+ vq->callfd = file->fd;
+
+ return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_KICK
+ * The virtio device sends an eventfd that it can use to notify us.
+ * This fd gets copied into our process space.
+ */
+int
+vhost_set_vring_kick(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+ struct virtio_net *dev;
+ struct vhost_virtqueue *vq;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ /* file->index refers to the queue index. The txq is 1, rxq is 0. */
+ vq = dev->virtqueue[file->index];
+
+ if (vq->kickfd >= 0)
+ close(vq->kickfd);
+
+ vq->kickfd = file->fd;
+
+ return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_NET_SET_BACKEND
+ * To complete device initialisation when the virtio driver is loaded,
+ * we are provided with a valid fd for a tap device (not used by us).
+ * If this happens then we can add the device to a data core.
+ * When the virtio driver is removed we get fd=-1.
+ * At that point we remove the device from the data core.
+ * The device will still exist in the device configuration linked list.
+ */
+int
+vhost_set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+ struct virtio_net *dev;
+
+ dev = get_device(ctx);
+ if (dev == NULL)
+ return -1;
+
+ /* file->index refers to the queue index. The txq is 1, rxq is 0. */
+ dev->virtqueue[file->index]->backend = file->fd;
+
+ /*
+ * If the device isn't already running and both backend fds are set,
+ * we add the device.
+ */
+ if (!(dev->flags & VIRTIO_DEV_RUNNING)) {
+ if (((int)dev->virtqueue[VIRTIO_TXQ]->backend != VIRTIO_DEV_STOPPED) &&
+ ((int)dev->virtqueue[VIRTIO_RXQ]->backend != VIRTIO_DEV_STOPPED)) {
+ return notify_ops->new_device(dev);
+ }
+ /* Otherwise we remove it. */
+ } else
+ if (file->fd == VIRTIO_DEV_STOPPED)
+ notify_ops->destroy_device(dev);
+ return 0;
+}
+
+int rte_vhost_enable_guest_notification(struct virtio_net *dev,
+ uint16_t queue_id, int enable)
+{
+ if (enable) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "guest notification isn't supported.\n");
+ return -1;
+ }
+
+ dev->virtqueue[queue_id]->used->flags = VRING_USED_F_NO_NOTIFY;
+ return 0;
+}
+
+uint64_t rte_vhost_feature_get(void)
+{
+ return VHOST_FEATURES;
+}
+
+int rte_vhost_feature_disable(uint64_t feature_mask)
+{
+ VHOST_FEATURES = VHOST_FEATURES & ~feature_mask;
+ return 0;
+}
+
+int rte_vhost_feature_enable(uint64_t feature_mask)
+{
+ if ((feature_mask & VHOST_SUPPORTED_FEATURES) == feature_mask) {
+ VHOST_FEATURES = VHOST_FEATURES | feature_mask;
+ return 0;
+ }
+ return -1;
+}
+
+/*
+ * Register ops so that we can add/remove device to data core.
+ */
+int
+rte_vhost_driver_callback_register(struct virtio_net_device_ops const * const ops)
+{
+ notify_ops = ops;
+
+ return 0;
+}