first version

1 files changed, 1163 insertions, 0 deletions

diff --git a/src/dpdk_lib18/librte_vhost/virtio-net.c b/src/dpdk_lib18/librte_vhost/virtio-net.c
new file mode 100755
index 00000000..b041849d
--- /dev/null
+++ b/src/dpdk_lib18/librte_vhost/virtio-net.c
@@ -0,0 +1,1163 @@
+/*-
+ *   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 <dirent.h>
+#include <fuse/cuse_lowlevel.h>
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <sys/eventfd.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include <sys/socket.h>
+#include <linux/if_tun.h>
+#include <linux/if.h>
+
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+#include <rte_memory.h>
+#include <rte_virtio_net.h>
+
+#include "vhost-net-cdev.h"
+#include "eventfd_link/eventfd_link.h"
+
+/*
+ * Device linked list structure for configuration.
+ */
+struct virtio_net_config_ll {
+	struct virtio_net dev;			/* Virtio device.*/
+	struct virtio_net_config_ll *next;	/* Next dev on linked list.*/
+};
+
+const char eventfd_cdev[] = "/dev/eventfd-link";
+
+/* device ops to add/remove device to/from data core. */
+static struct virtio_net_device_ops const *notify_ops;
+/* root address of the linked list of managed virtio devices */
+static struct virtio_net_config_ll *ll_root;
+
+/* Features supported by this lib. */
+#define VHOST_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
+				  (1ULL << VIRTIO_NET_F_CTRL_RX))
+static uint64_t VHOST_FEATURES = VHOST_SUPPORTED_FEATURES;
+
+/* Line size for reading maps file. */
+static const uint32_t BUFSIZE = PATH_MAX;
+
+/* Size of prot char array in procmap. */
+#define PROT_SZ 5
+
+/* Number of elements in procmap struct. */
+#define PROCMAP_SZ 8
+
+/* Structure containing information gathered from maps file. */
+struct procmap {
+	uint64_t va_start;	/* Start virtual address in file. */
+	uint64_t len;		/* Size of file. */
+	uint64_t pgoff;		/* Not used. */
+	uint32_t maj;		/* Not used. */
+	uint32_t min;		/* Not used. */
+	uint32_t ino;		/* Not used. */
+	char prot[PROT_SZ];	/* Not used. */
+	char fname[PATH_MAX];	/* File name. */
+};
+
+/*
+ * 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 = dev->mem->mapped_address + qemu_va -
+					dev->mem->base_address;
+			break;
+		}
+	}
+	return vhost_va;
+}
+
+/*
+ * Locate the file containing QEMU's memory space and
+ * map it to our address space.
+ */
+static int
+host_memory_map(struct virtio_net *dev, struct virtio_memory *mem,
+	pid_t pid, uint64_t addr)
+{
+	struct dirent *dptr = NULL;
+	struct procmap procmap;
+	DIR *dp = NULL;
+	int fd;
+	int i;
+	char memfile[PATH_MAX];
+	char mapfile[PATH_MAX];
+	char procdir[PATH_MAX];
+	char resolved_path[PATH_MAX];
+	char *path = NULL;
+	FILE *fmap;
+	void *map;
+	uint8_t found = 0;
+	char line[BUFSIZE];
+	char dlm[] = "-   :   ";
+	char *str, *sp, *in[PROCMAP_SZ];
+	char *end = NULL;
+
+	/* Path where mem files are located. */
+	snprintf(procdir, PATH_MAX, "/proc/%u/fd/", pid);
+	/* Maps file used to locate mem file. */
+	snprintf(mapfile, PATH_MAX, "/proc/%u/maps", pid);
+
+	fmap = fopen(mapfile, "r");
+	if (fmap == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to open maps file for pid %d\n",
+			dev->device_fh, pid);
+		return -1;
+	}
+
+	/* Read through maps file until we find out base_address. */
+	while (fgets(line, BUFSIZE, fmap) != 0) {
+		str = line;
+		errno = 0;
+		/* Split line into fields. */
+		for (i = 0; i < PROCMAP_SZ; i++) {
+			in[i] = strtok_r(str, &dlm[i], &sp);
+			if ((in[i] == NULL) || (errno != 0)) {
+				fclose(fmap);
+				return -1;
+			}
+			str = NULL;
+		}
+
+		/* Convert/Copy each field as needed. */
+		procmap.va_start = strtoull(in[0], &end, 16);
+		if ((in[0] == '\0') || (end == NULL) || (*end != '\0') ||
+			(errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.len = strtoull(in[1], &end, 16);
+		if ((in[1] == '\0') || (end == NULL) || (*end != '\0') ||
+			(errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.pgoff = strtoull(in[3], &end, 16);
+		if ((in[3] == '\0') || (end == NULL) || (*end != '\0') ||
+			(errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.maj = strtoul(in[4], &end, 16);
+		if ((in[4] == '\0') || (end == NULL) || (*end != '\0') ||
+			(errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.min = strtoul(in[5], &end, 16);
+		if ((in[5] == '\0') || (end == NULL) || (*end != '\0') ||
+			(errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.ino = strtoul(in[6], &end, 16);
+		if ((in[6] == '\0') || (end == NULL) || (*end != '\0') ||
+			(errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		memcpy(&procmap.prot, in[2], PROT_SZ);
+		memcpy(&procmap.fname, in[7], PATH_MAX);
+
+		if (procmap.va_start == addr) {
+			procmap.len = procmap.len - procmap.va_start;
+			found = 1;
+			break;
+		}
+	}
+	fclose(fmap);
+
+	if (!found) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to find memory file in pid %d maps file\n",
+			dev->device_fh, pid);
+		return -1;
+	}
+
+	/* Find the guest memory file among the process fds. */
+	dp = opendir(procdir);
+	if (dp == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Cannot open pid %d process directory\n",
+			dev->device_fh, pid);
+		return -1;
+	}
+
+	found = 0;
+
+	/* Read the fd directory contents. */
+	while (NULL != (dptr = readdir(dp))) {
+		snprintf(memfile, PATH_MAX, "/proc/%u/fd/%s",
+				pid, dptr->d_name);
+		path = realpath(memfile, resolved_path);
+		if ((path == NULL) && (strlen(resolved_path) == 0)) {
+			RTE_LOG(ERR, VHOST_CONFIG,
+				"(%"PRIu64") Failed to resolve fd directory\n",
+				dev->device_fh);
+			closedir(dp);
+			return -1;
+		}
+		if (strncmp(resolved_path, procmap.fname,
+			strnlen(procmap.fname, PATH_MAX)) == 0) {
+			found = 1;
+			break;
+		}
+	}
+
+	closedir(dp);
+
+	if (found == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to find memory file for pid %d\n",
+			dev->device_fh, pid);
+		return -1;
+	}
+	/* Open the shared memory file and map the memory into this process. */
+	fd = open(memfile, O_RDWR);
+
+	if (fd == -1) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to open %s for pid %d\n",
+			dev->device_fh, memfile, pid);
+		return -1;
+	}
+
+	map = mmap(0, (size_t)procmap.len, PROT_READ|PROT_WRITE,
+		MAP_POPULATE|MAP_SHARED, fd, 0);
+	close(fd);
+
+	if (map == MAP_FAILED) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Error mapping the file %s for pid %d\n",
+			dev->device_fh, memfile, pid);
+		return -1;
+	}
+
+	/* Store the memory address and size in the device data structure */
+	mem->mapped_address = (uint64_t)(uintptr_t)map;
+	mem->mapped_size = procmap.len;
+
+	LOG_DEBUG(VHOST_CONFIG,
+		"(%"PRIu64") Mem File: %s->%s - Size: %llu - VA: %p\n",
+		dev->device_fh,
+		memfile, resolved_path,
+		(unsigned long long)mem->mapped_size, map);
+
+	return 0;
+}
+
+/*
+ * Retrieves an entry from the devices configuration linked list.
+ */
+static struct virtio_net_config_ll *
+get_config_ll_entry(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev = ll_root;
+
+	/* Loop through linked list until the device_fh is found. */
+	while (ll_dev != NULL) {
+		if (ll_dev->dev.device_fh == ctx.fh)
+			return ll_dev;
+		ll_dev = ll_dev->next;
+	}
+
+	return NULL;
+}
+
+/*
+ * Searches the configuration core linked list and
+ * retrieves the device if it exists.
+ */
+static struct virtio_net *
+get_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev;
+
+	ll_dev = get_config_ll_entry(ctx);
+
+	if (ll_dev)
+		return &ll_dev->dev;
+
+	RTE_LOG(ERR, VHOST_CONFIG,
+		"(%"PRIu64") Device not found in linked list.\n", ctx.fh);
+	return NULL;
+}
+
+/*
+ * Add entry containing a device to the device configuration linked list.
+ */
+static void
+add_config_ll_entry(struct virtio_net_config_ll *new_ll_dev)
+{
+	struct virtio_net_config_ll *ll_dev = ll_root;
+
+	/* If ll_dev == NULL then this is the first device so go to else */
+	if (ll_dev) {
+		/* If the 1st device_fh != 0 then we insert our device here. */
+		if (ll_dev->dev.device_fh != 0) {
+			new_ll_dev->dev.device_fh = 0;
+			new_ll_dev->next = ll_dev;
+			ll_root = new_ll_dev;
+		} else {
+			/*
+			 * Increment through the ll until we find un unused
+			 * device_fh. Insert the device at that entry.
+			 */
+			while ((ll_dev->next != NULL) &&
+				(ll_dev->dev.device_fh ==
+					(ll_dev->next->dev.device_fh - 1)))
+				ll_dev = ll_dev->next;
+
+			new_ll_dev->dev.device_fh = ll_dev->dev.device_fh + 1;
+			new_ll_dev->next = ll_dev->next;
+			ll_dev->next = new_ll_dev;
+		}
+	} else {
+		ll_root = new_ll_dev;
+		ll_root->dev.device_fh = 0;
+	}
+
+}
+
+/*
+ * Unmap any memory, close any file descriptors and
+ * free any memory owned by a device.
+ */
+static void
+cleanup_device(struct virtio_net *dev)
+{
+	/* Unmap QEMU memory file if mapped. */
+	if (dev->mem) {
+		munmap((void *)(uintptr_t)dev->mem->mapped_address,
+			(size_t)dev->mem->mapped_size);
+		free(dev->mem);
+	}
+
+	/* Close any event notifiers opened by device. */
+	if (dev->virtqueue[VIRTIO_RXQ]->callfd)
+		close((int)dev->virtqueue[VIRTIO_RXQ]->callfd);
+	if (dev->virtqueue[VIRTIO_RXQ]->kickfd)
+		close((int)dev->virtqueue[VIRTIO_RXQ]->kickfd);
+	if (dev->virtqueue[VIRTIO_TXQ]->callfd)
+		close((int)dev->virtqueue[VIRTIO_TXQ]->callfd);
+	if (dev->virtqueue[VIRTIO_TXQ]->kickfd)
+		close((int)dev->virtqueue[VIRTIO_TXQ]->kickfd);
+}
+
+/*
+ * Release virtqueues and device memory.
+ */
+static void
+free_device(struct virtio_net_config_ll *ll_dev)
+{
+	/* Free any malloc'd memory */
+	free(ll_dev->dev.virtqueue[VIRTIO_RXQ]);
+	free(ll_dev->dev.virtqueue[VIRTIO_TXQ]);
+	free(ll_dev);
+}
+
+/*
+ * Remove an entry from the device configuration linked list.
+ */
+static struct virtio_net_config_ll *
+rm_config_ll_entry(struct virtio_net_config_ll *ll_dev,
+	struct virtio_net_config_ll *ll_dev_last)
+{
+	/* First remove the device and then clean it up. */
+	if (ll_dev == ll_root) {
+		ll_root = ll_dev->next;
+		cleanup_device(&ll_dev->dev);
+		free_device(ll_dev);
+		return ll_root;
+	} else {
+		if (likely(ll_dev_last != NULL)) {
+			ll_dev_last->next = ll_dev->next;
+			cleanup_device(&ll_dev->dev);
+			free_device(ll_dev);
+			return ll_dev_last->next;
+		} else {
+			cleanup_device(&ll_dev->dev);
+			free_device(ll_dev);
+			RTE_LOG(ERR, VHOST_CONFIG,
+				"Remove entry from config_ll failed\n");
+			return NULL;
+		}
+	}
+}
+
+/*
+ *  Initialise all variables in device structure.
+ */
+static void
+init_device(struct virtio_net *dev)
+{
+	uint64_t vq_offset;
+
+	/*
+	 * Virtqueues have already been malloced so
+	 * we don't want to set them to NULL.
+	 */
+	vq_offset = offsetof(struct virtio_net, mem);
+
+	/* Set everything to 0. */
+	memset((void *)(uintptr_t)((uint64_t)(uintptr_t)dev + vq_offset), 0,
+		(sizeof(struct virtio_net) - (size_t)vq_offset));
+	memset(dev->virtqueue[VIRTIO_RXQ], 0, sizeof(struct vhost_virtqueue));
+	memset(dev->virtqueue[VIRTIO_TXQ], 0, sizeof(struct vhost_virtqueue));
+
+	/* Backends are set to -1 indicating an inactive device. */
+	dev->virtqueue[VIRTIO_RXQ]->backend = VIRTIO_DEV_STOPPED;
+	dev->virtqueue[VIRTIO_TXQ]->backend = VIRTIO_DEV_STOPPED;
+}
+
+/*
+ * 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.
+ */
+static int
+new_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *new_ll_dev;
+	struct vhost_virtqueue *virtqueue_rx, *virtqueue_tx;
+
+	/* Setup device and virtqueues. */
+	new_ll_dev = malloc(sizeof(struct virtio_net_config_ll));
+	if (new_ll_dev == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for dev.\n",
+			ctx.fh);
+		return -1;
+	}
+
+	virtqueue_rx = malloc(sizeof(struct vhost_virtqueue));
+	if (virtqueue_rx == NULL) {
+		free(new_ll_dev);
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for rxq.\n",
+			ctx.fh);
+		return -1;
+	}
+
+	virtqueue_tx = malloc(sizeof(struct vhost_virtqueue));
+	if (virtqueue_tx == NULL) {
+		free(virtqueue_rx);
+		free(new_ll_dev);
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for txq.\n",
+			ctx.fh);
+		return -1;
+	}
+
+	new_ll_dev->dev.virtqueue[VIRTIO_RXQ] = virtqueue_rx;
+	new_ll_dev->dev.virtqueue[VIRTIO_TXQ] = virtqueue_tx;
+
+	/* Initialise device and virtqueues. */
+	init_device(&new_ll_dev->dev);
+
+	new_ll_dev->next = NULL;
+
+	/* Add entry to device configuration linked list. */
+	add_config_ll_entry(new_ll_dev);
+
+	return new_ll_dev->dev.device_fh;
+}
+
+/*
+ * Function is called from the CUSE release function. This function will
+ * cleanup the device and remove it from device configuration linked list.
+ */
+static void
+destroy_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev_cur_ctx, *ll_dev_last = NULL;
+	struct virtio_net_config_ll *ll_dev_cur = ll_root;
+
+	/* Find the linked list entry for the device to be removed. */
+	ll_dev_cur_ctx = get_config_ll_entry(ctx);
+	while (ll_dev_cur != NULL) {
+		/*
+		 * If the device is found or
+		 * a device that doesn't exist is found then it is removed.
+		 */
+		if (ll_dev_cur == ll_dev_cur_ctx) {
+			/*
+			 * If the device is running on a data core then call
+			 * the function to remove it from the data core.
+			 */
+			if ((ll_dev_cur->dev.flags & VIRTIO_DEV_RUNNING))
+				notify_ops->destroy_device(&(ll_dev_cur->dev));
+			ll_dev_cur = rm_config_ll_entry(ll_dev_cur,
+					ll_dev_last);
+		} else {
+			ll_dev_last = ll_dev_cur;
+			ll_dev_cur = ll_dev_cur->next;
+		}
+	}
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_OWNER
+ * This function just returns success at the moment unless
+ * the device hasn't been initialised.
+ */
+static int
+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
+ */
+static int
+reset_owner(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev;
+
+	ll_dev = get_config_ll_entry(ctx);
+
+	cleanup_device(&ll_dev->dev);
+	init_device(&ll_dev->dev);
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_GET_FEATURES
+ * The features that we support are requested.
+ */
+static int
+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.
+ */
+static int
+set_features(struct vhost_device_ctx ctx, uint64_t *pu)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+	if (*pu & ~VHOST_FEATURES)
+		return -1;
+
+	/* Store the negotiated feature list for the device. */
+	dev->features = *pu;
+
+	/* Set the vhost_hlen depending on if VIRTIO_NET_F_MRG_RXBUF is set. */
+	if (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) {
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") Mergeable RX buffers enabled\n",
+			dev->device_fh);
+		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen =
+			sizeof(struct virtio_net_hdr_mrg_rxbuf);
+		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen =
+			sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	} else {
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") Mergeable RX buffers disabled\n",
+			dev->device_fh);
+		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen =
+			sizeof(struct virtio_net_hdr);
+		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen =
+			sizeof(struct virtio_net_hdr);
+	}
+	return 0;
+}
+
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_MEM_TABLE
+ * This function creates and populates the memory structure for the device.
+ * This includes storing offsets used to translate buffer addresses.
+ */
+static int
+set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr,
+	uint32_t nregions)
+{
+	struct virtio_net *dev;
+	struct vhost_memory_region *mem_regions;
+	struct virtio_memory *mem;
+	uint64_t size = offsetof(struct vhost_memory, regions);
+	uint32_t regionidx, valid_regions;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	if (dev->mem) {
+		munmap((void *)(uintptr_t)dev->mem->mapped_address,
+			(size_t)dev->mem->mapped_size);
+		free(dev->mem);
+	}
+
+	/* Malloc the memory structure depending on the number of regions. */
+	mem = calloc(1, sizeof(struct virtio_memory) +
+		(sizeof(struct virtio_memory_regions) * nregions));
+	if (mem == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for dev->mem.\n",
+			dev->device_fh);
+		return -1;
+	}
+
+	mem->nregions = nregions;
+
+	mem_regions = (void *)(uintptr_t)
+			((uint64_t)(uintptr_t)mem_regions_addr + size);
+
+	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
+		/* Populate the region structure for each region. */
+		mem->regions[regionidx].guest_phys_address =
+			mem_regions[regionidx].guest_phys_addr;
+		mem->regions[regionidx].guest_phys_address_end =
+			mem->regions[regionidx].guest_phys_address +
+			mem_regions[regionidx].memory_size;
+		mem->regions[regionidx].memory_size =
+			mem_regions[regionidx].memory_size;
+		mem->regions[regionidx].userspace_address =
+			mem_regions[regionidx].userspace_addr;
+
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") REGION: %u - GPA: %p - QEMU VA: %p - SIZE (%"PRIu64")\n", dev->device_fh,
+			regionidx,
+			(void *)(uintptr_t)mem->regions[regionidx].guest_phys_address,
+			(void *)(uintptr_t)mem->regions[regionidx].userspace_address,
+			mem->regions[regionidx].memory_size);
+
+		/*set the base address mapping*/
+		if (mem->regions[regionidx].guest_phys_address == 0x0) {
+			mem->base_address =
+				mem->regions[regionidx].userspace_address;
+			/* Map VM memory file */
+			if (host_memory_map(dev, mem, ctx.pid,
+				mem->base_address) != 0) {
+				free(mem);
+				return -1;
+			}
+		}
+	}
+
+	/* Check that we have a valid base address. */
+	if (mem->base_address == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find base address of qemu memory file.\n", dev->device_fh);
+		free(mem);
+		return -1;
+	}
+
+	/*
+	 * Check if all of our regions have valid mappings.
+	 * Usually one does not exist in the QEMU memory file.
+	 */
+	valid_regions = mem->nregions;
+	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
+		if ((mem->regions[regionidx].userspace_address <
+			mem->base_address) ||
+			(mem->regions[regionidx].userspace_address >
+			(mem->base_address + mem->mapped_size)))
+				valid_regions--;
+	}
+
+	/*
+	 * If a region does not have a valid mapping,
+	 * we rebuild our memory struct to contain only valid entries.
+	 */
+	if (valid_regions != mem->nregions) {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Not all memory regions exist in the QEMU mem file. Re-populating mem structure\n",
+			dev->device_fh);
+
+		/*
+		 * Re-populate the memory structure with only valid regions.
+		 * Invalid regions are over-written with memmove.
+		 */
+		valid_regions = 0;
+
+		for (regionidx = mem->nregions; 0 != regionidx--;) {
+			if ((mem->regions[regionidx].userspace_address <
+				mem->base_address) ||
+				(mem->regions[regionidx].userspace_address >
+				(mem->base_address + mem->mapped_size))) {
+				memmove(&mem->regions[regionidx],
+					&mem->regions[regionidx + 1],
+					sizeof(struct virtio_memory_regions) *
+						valid_regions);
+			} else {
+				valid_regions++;
+			}
+		}
+	}
+	mem->nregions = valid_regions;
+	dev->mem = mem;
+
+	/*
+	 * Calculate the address offset for each region.
+	 * This offset is used to identify the vhost virtual address
+	 * corresponding to a QEMU guest physical address.
+	 */
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		dev->mem->regions[regionidx].address_offset =
+			dev->mem->regions[regionidx].userspace_address -
+				dev->mem->base_address +
+				dev->mem->mapped_address -
+				dev->mem->regions[regionidx].guest_phys_address;
+
+	}
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_NUM
+ * The virtio device sends us the size of the descriptor ring.
+ */
+static int
+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;
+}
+
+/*
+ * 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.
+ */
+static int
+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)
+		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;
+	}
+
+	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;
+	}
+
+	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);
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_BASE
+ * The virtio device sends us the available ring last used index.
+ */
+static int
+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.
+ */
+static int
+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;
+}
+
+/*
+ * This function uses the eventfd_link kernel module to copy an eventfd file
+ * descriptor provided by QEMU in to our process space.
+ */
+static int
+eventfd_copy(struct virtio_net *dev, struct eventfd_copy *eventfd_copy)
+{
+	int eventfd_link, ret;
+
+	/* Open the character device to the kernel module. */
+	eventfd_link = open(eventfd_cdev, O_RDWR);
+	if (eventfd_link < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") eventfd_link module is not loaded\n",
+			dev->device_fh);
+		return -1;
+	}
+
+	/* Call the IOCTL to copy the eventfd. */
+	ret = ioctl(eventfd_link, EVENTFD_COPY, eventfd_copy);
+	close(eventfd_link);
+
+	if (ret < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") EVENTFD_COPY ioctl failed\n",
+			dev->device_fh);
+		return -1;
+	}
+
+	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.
+ */
+static int
+set_vring_call(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+	struct virtio_net *dev;
+	struct eventfd_copy	eventfd_kick;
+	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)
+		close((int)vq->kickfd);
+
+	/* Populate the eventfd_copy structure and call eventfd_copy. */
+	vq->kickfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+	eventfd_kick.source_fd = vq->kickfd;
+	eventfd_kick.target_fd = file->fd;
+	eventfd_kick.target_pid = ctx.pid;
+
+	if (eventfd_copy(dev, &eventfd_kick))
+		return -1;
+
+	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.
+ */
+static int
+set_vring_kick(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+	struct virtio_net *dev;
+	struct eventfd_copy eventfd_call;
+	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->callfd)
+		close((int)vq->callfd);
+
+	/* Populate the eventfd_copy structure and call eventfd_copy. */
+	vq->callfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+	eventfd_call.source_fd = vq->callfd;
+	eventfd_call.target_fd = file->fd;
+	eventfd_call.target_pid = ctx.pid;
+
+	if (eventfd_copy(dev, &eventfd_call))
+		return -1;
+
+	return 0;
+}
+
+/*
+ * Function to get the tap device name from the provided file descriptor and
+ * save it in the device structure.
+ */
+static int
+get_ifname(struct virtio_net *dev, int tap_fd, int pid)
+{
+	struct eventfd_copy fd_tap;
+	struct ifreq ifr;
+	uint32_t size, ifr_size;
+	int ret;
+
+	fd_tap.source_fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+	fd_tap.target_fd = tap_fd;
+	fd_tap.target_pid = pid;
+
+	if (eventfd_copy(dev, &fd_tap))
+		return -1;
+
+	ret = ioctl(fd_tap.source_fd, TUNGETIFF, &ifr);
+
+	if (close(fd_tap.source_fd) < 0)
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") fd close failed\n",
+			dev->device_fh);
+
+	if (ret >= 0) {
+		ifr_size = strnlen(ifr.ifr_name, sizeof(ifr.ifr_name));
+		size = ifr_size > sizeof(dev->ifname) ?
+				sizeof(dev->ifname) : ifr_size;
+
+		strncpy(dev->ifname, ifr.ifr_name, size);
+	} else
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") TUNGETIFF ioctl failed\n",
+			dev->device_fh);
+
+	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.
+ */
+static int
+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)) {
+			get_ifname(dev, file->fd, ctx.pid);
+			return notify_ops->new_device(dev);
+		}
+	/* Otherwise we remove it. */
+	} else
+		if (file->fd == VIRTIO_DEV_STOPPED)
+			notify_ops->destroy_device(dev);
+	return 0;
+}
+
+/*
+ * Function pointers are set for the device operations to allow CUSE to call
+ * functions when an IOCTL, device_add or device_release is received.
+ */
+static const struct vhost_net_device_ops vhost_device_ops = {
+	.new_device = new_device,
+	.destroy_device = destroy_device,
+
+	.get_features = get_features,
+	.set_features = set_features,
+
+	.set_mem_table = set_mem_table,
+
+	.set_vring_num = set_vring_num,
+	.set_vring_addr = set_vring_addr,
+	.set_vring_base = set_vring_base,
+	.get_vring_base = get_vring_base,
+
+	.set_vring_kick = set_vring_kick,
+	.set_vring_call = set_vring_call,
+
+	.set_backend = set_backend,
+
+	.set_owner = set_owner,
+	.reset_owner = reset_owner,
+};
+
+/*
+ * Called by main to setup callbacks when registering CUSE device.
+ */
+struct vhost_net_device_ops const *
+get_virtio_net_callbacks(void)
+{
+	return &vhost_device_ops;
+}
+
+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 =
+		enable ? 0 : 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;
+}