[dpdk-dev] [PATCH v3] lib/librte_vhost: vhost library support to facilitate integration with DPDK accelerated vswitch.

Xie, Huawei huawei.xie at intel.com
Tue Aug 5 17:56:26 CEST 2014


This v3 patch fixes plenty of checkpatch issues.

> -----Original Message-----
> From: Xie, Huawei
> Sent: Tuesday, August 05, 2014 11:54 PM
> To: dev at dpdk.org
> Cc: Xie, Huawei
> Subject: [PATCH v3] lib/librte_vhost: vhost library support to facilitate
> integration with DPDK accelerated vswitch.
> 
> Signed-off-by: Huawei Xie <huawei.xie at intel.com>
> Acked-by: Konstantin Ananyev <konstantin.ananyev at intel.com>
> Acked-by: Tommy Long <thomas.long at intel.com>
> ---
>  config/common_linuxapp                       |    7 +
>  lib/Makefile                                 |    1 +
>  lib/librte_vhost/Makefile                    |   48 ++
>  lib/librte_vhost/eventfd_link/Makefile       |   39 +
>  lib/librte_vhost/eventfd_link/eventfd_link.c |  194 +++++
>  lib/librte_vhost/eventfd_link/eventfd_link.h |   40 +
>  lib/librte_vhost/rte_virtio_net.h            |  192 +++++
>  lib/librte_vhost/vhost-net-cdev.c            |  363 ++++++++++
>  lib/librte_vhost/vhost-net-cdev.h            |  109 +++
>  lib/librte_vhost/vhost_rxtx.c                |  292 ++++++++
>  lib/librte_vhost/virtio-net.c                | 1002 ++++++++++++++++++++++++++
>  11 files changed, 2287 insertions(+)
>  create mode 100644 lib/librte_vhost/Makefile
>  create mode 100644 lib/librte_vhost/eventfd_link/Makefile
>  create mode 100644 lib/librte_vhost/eventfd_link/eventfd_link.c
>  create mode 100644 lib/librte_vhost/eventfd_link/eventfd_link.h
>  create mode 100644 lib/librte_vhost/rte_virtio_net.h
>  create mode 100644 lib/librte_vhost/vhost-net-cdev.c
>  create mode 100644 lib/librte_vhost/vhost-net-cdev.h
>  create mode 100644 lib/librte_vhost/vhost_rxtx.c
>  create mode 100644 lib/librte_vhost/virtio-net.c
> 
> diff --git a/config/common_linuxapp b/config/common_linuxapp
> index 9047975..c7c1c83 100644
> --- a/config/common_linuxapp
> +++ b/config/common_linuxapp
> @@ -390,6 +390,13 @@ CONFIG_RTE_KNI_VHOST_DEBUG_RX=n
>  CONFIG_RTE_KNI_VHOST_DEBUG_TX=n
> 
>  #
> +# Compile vhost library
> +# fuse, fuse-devel, kernel-modules-extra packages are needed
> +#
> +CONFIG_RTE_LIBRTE_VHOST=n
> +CONFIG_RTE_LIBRTE_VHOST_DEBUG=n
> +
> +#
>  #Compile Xen domain0 support
>  #
>  CONFIG_RTE_LIBRTE_XEN_DOM0=n
> diff --git a/lib/Makefile b/lib/Makefile
> index 10c5bb3..007c174 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -60,6 +60,7 @@ DIRS-$(CONFIG_RTE_LIBRTE_METER) += librte_meter
>  DIRS-$(CONFIG_RTE_LIBRTE_SCHED) += librte_sched
>  DIRS-$(CONFIG_RTE_LIBRTE_KVARGS) += librte_kvargs
>  DIRS-$(CONFIG_RTE_LIBRTE_DISTRIBUTOR) += librte_distributor
> +DIRS-$(CONFIG_RTE_LIBRTE_VHOST) += librte_vhost
>  DIRS-$(CONFIG_RTE_LIBRTE_PORT) += librte_port
>  DIRS-$(CONFIG_RTE_LIBRTE_TABLE) += librte_table
>  DIRS-$(CONFIG_RTE_LIBRTE_PIPELINE) += librte_pipeline
> diff --git a/lib/librte_vhost/Makefile b/lib/librte_vhost/Makefile
> new file mode 100644
> index 0000000..6ad706d
> --- /dev/null
> +++ b/lib/librte_vhost/Makefile
> @@ -0,0 +1,48 @@
> +#   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 $(RTE_SDK)/mk/rte.vars.mk
> +
> +# library name
> +LIB = librte_vhost.a
> +
> +CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR) -O3 -D_FILE_OFFSET_BITS=64 -lfuse
> +LDFLAGS += -lfuse
> +# all source are stored in SRCS-y
> +SRCS-$(CONFIG_RTE_LIBRTE_VHOST) := vhost-net-cdev.c virtio-net.c
> vhost_rxtx.c
> +
> +# install includes
> +SYMLINK-$(CONFIG_RTE_LIBRTE_VHOST)-include += rte_virtio_net.h
> +
> +# this lib needs eal
> +DEPDIRS-$(CONFIG_RTE_LIBRTE_VHOST) += lib/librte_eal lib/librte_mbuf
> +
> +include $(RTE_SDK)/mk/rte.lib.mk
> diff --git a/lib/librte_vhost/eventfd_link/Makefile
> b/lib/librte_vhost/eventfd_link/Makefile
> new file mode 100644
> index 0000000..fc3927b
> --- /dev/null
> +++ b/lib/librte_vhost/eventfd_link/Makefile
> @@ -0,0 +1,39 @@
> +#   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.
> +
> +obj-m += eventfd_link.o
> +
> +
> +all:
> +	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
> +
> +clean:
> +	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
> diff --git a/lib/librte_vhost/eventfd_link/eventfd_link.c
> b/lib/librte_vhost/eventfd_link/eventfd_link.c
> new file mode 100644
> index 0000000..4c9b628
> --- /dev/null
> +++ b/lib/librte_vhost/eventfd_link/eventfd_link.c
> @@ -0,0 +1,194 @@
> +/*-
> + * GPL LICENSE SUMMARY
> + *
> + *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
> + *
> + *   This program is free software; you can redistribute it and/or modify
> + *   it under the terms of version 2 of the GNU General Public License as
> + *   published by the Free Software Foundation.
> + *
> + *   This program is distributed in the hope that it will be useful, but
> + *   WITHOUT ANY WARRANTY; without even the implied warranty of
> + *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + *   General Public License for more details.
> + *
> + *   You should have received a copy of the GNU General Public License
> + *   along with this program; If not, see <http://www.gnu.org/licenses/>.
> + *   The full GNU General Public License is included in this distribution
> + *   in the file called LICENSE.GPL.
> + *
> + *   Contact Information:
> + *   Intel Corporation
> + */
> +
> +#include <linux/eventfd.h>
> +#include <linux/miscdevice.h>
> +#include <linux/module.h>
> +#include <linux/moduleparam.h>
> +#include <linux/rcupdate.h>
> +#include <linux/file.h>
> +#include <linux/slab.h>
> +#include <linux/fs.h>
> +#include <linux/mmu_context.h>
> +#include <linux/sched.h>
> +#include <asm/mmu_context.h>
> +#include <linux/fdtable.h>
> +
> +#include "eventfd_link.h"
> +
> +
> +/*
> + * get_files_struct is copied from fs/file.c
> + */
> +struct files_struct *
> +get_files_struct(struct task_struct *task)
> +{
> +	struct files_struct *files;
> +
> +	task_lock(task);
> +	files = task->files;
> +	if (files)
> +		atomic_inc(&files->count);
> +	task_unlock(task);
> +
> +	return files;
> +}
> +
> +/*
> + * put_files_struct is extracted from fs/file.c
> + */
> +void
> +put_files_struct(struct files_struct *files)
> +{
> +	if (atomic_dec_and_test(&files->count))
> +		BUG();
> +}
> +
> +
> +static long
> +eventfd_link_ioctl(struct file *f, unsigned int ioctl, unsigned long arg)
> +{
> +	void __user *argp = (void __user *) arg;
> +	struct task_struct *task_target = NULL;
> +	struct file *file;
> +	struct files_struct *files;
> +	struct fdtable *fdt;
> +	struct eventfd_copy eventfd_copy;
> +
> +	switch (ioctl) {
> +	case EVENTFD_COPY:
> +		if (copy_from_user(&eventfd_copy, argp, sizeof(struct
> eventfd_copy)))
> +			return -EFAULT;
> +
> +		/*
> +		 * Find the task struct for the target pid
> +		 */
> +		task_target =
> +			pid_task(find_vpid(eventfd_copy.target_pid),
> PIDTYPE_PID);
> +		if (task_target == NULL) {
> +			printk(KERN_DEBUG "Failed to get mem ctx for target
> pid\n");
> +			return -EFAULT;
> +		}
> +
> +		files = get_files_struct(current);
> +		if (files == NULL) {
> +			printk(KERN_DEBUG "Failed to get files struct\n");
> +			return -EFAULT;
> +		}
> +
> +		rcu_read_lock();
> +		file = fcheck_files(files, eventfd_copy.source_fd);
> +		if (file) {
> +			if (file->f_mode & FMODE_PATH
> +				|| !atomic_long_inc_not_zero(&file->f_count))
> +				file = NULL;
> +		}
> +		rcu_read_unlock();
> +		put_files_struct(files);
> +
> +		if (file == NULL) {
> +			printk(KERN_DEBUG "Failed to get file from source
> pid\n");
> +			return 0;
> +		}
> +
> +		/*
> +		 * Release the existing eventfd in the source process
> +		 */
> +		spin_lock(&files->file_lock);
> +		filp_close(file, files);
> +		fdt = files_fdtable(files);
> +		fdt->fd[eventfd_copy.source_fd] = NULL;
> +		spin_unlock(&files->file_lock);
> +
> +		/*
> +		 * Find the file struct associated with the target fd.
> +		 */
> +
> +		files = get_files_struct(task_target);
> +		if (files == NULL) {
> +			printk(KERN_DEBUG "Failed to get files struct\n");
> +			return -EFAULT;
> +		}
> +
> +		rcu_read_lock();
> +		file = fcheck_files(files, eventfd_copy.target_fd);
> +		if (file) {
> +			if (file->f_mode & FMODE_PATH
> +				|| !atomic_long_inc_not_zero(&file->f_count))
> +				file = NULL;
> +		}
> +		rcu_read_unlock();
> +		put_files_struct(files);
> +
> +		if (file == NULL) {
> +			printk(KERN_DEBUG "Failed to get file from target
> pid\n");
> +			return 0;
> +		}
> +
> +
> +		/*
> +		 * Install the file struct from the target process into the
> +		 * file desciptor of the source process,
> +		 */
> +
> +		fd_install(eventfd_copy.source_fd, file);
> +
> +		return 0;
> +
> +	default:
> +		return -ENOIOCTLCMD;
> +	}
> +}
> +
> +static const struct file_operations eventfd_link_fops = {
> +	.owner = THIS_MODULE,
> +	.unlocked_ioctl = eventfd_link_ioctl,
> +};
> +
> +
> +static struct miscdevice eventfd_link_misc = {
> +	.name = "eventfd-link",
> +	.fops = &eventfd_link_fops,
> +};
> +
> +static int __init
> +eventfd_link_init(void)
> +{
> +	return misc_register(&eventfd_link_misc);
> +}
> +
> +module_init(eventfd_link_init);
> +
> +static void __exit
> +eventfd_link_exit(void)
> +{
> +	misc_deregister(&eventfd_link_misc);
> +}
> +
> +module_exit(eventfd_link_exit);
> +
> +MODULE_VERSION("0.0.1");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Anthony Fee");
> +MODULE_DESCRIPTION("Link eventfd");
> +MODULE_ALIAS("devname:eventfd-link");
> diff --git a/lib/librte_vhost/eventfd_link/eventfd_link.h
> b/lib/librte_vhost/eventfd_link/eventfd_link.h
> new file mode 100644
> index 0000000..38052e2
> --- /dev/null
> +++ b/lib/librte_vhost/eventfd_link/eventfd_link.h
> @@ -0,0 +1,40 @@
> +/*-
> + * GPL LICENSE SUMMARY
> + *
> + *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
> + *
> + *   This program is free software; you can redistribute it and/or modify
> + *   it under the terms of version 2 of the GNU General Public License as
> + *   published by the Free Software Foundation.
> + *
> + *   This program is distributed in the hope that it will be useful, but
> + *   WITHOUT ANY WARRANTY; without even the implied warranty of
> + *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + *   General Public License for more details.
> + *
> + *   You should have received a copy of the GNU General Public License
> + *   along with this program; If not, see <http://www.gnu.org/licenses/>.
> + *   The full GNU General Public License is included in this distribution
> + *   in the file called LICENSE.GPL.
> + *
> + *   Contact Information:
> + *   Intel Corporation
> + */
> +
> +#ifndef _EVENTFD_LINK_H_
> +#define _EVENTFD_LINK_H_
> +
> +/*
> + *	ioctl to copy an fd entry in calling process to an fd in a target process
> + */
> +#define EVENTFD_COPY 1
> +
> +/*
> + *	arguements for the EVENTFD_COPY ioctl
> + */
> +struct eventfd_copy {
> +	unsigned target_fd; /**< fd in the target pid */
> +	unsigned source_fd; /**< fd in the calling pid */
> +	pid_t target_pid;   /**< pid of the target pid */
> +};
> +#endif /* _EVENTFD_LINK_H_ */
> diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
> new file mode 100644
> index 0000000..7a05dab
> --- /dev/null
> +++ b/lib/librte_vhost/rte_virtio_net.h
> @@ -0,0 +1,192 @@
> +/*-
> + *   BSD LICENSE
> + *
> + *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
> + *   All rights reserved.
> + *
> + *   Redistribution and use in source and binary forms, with or without
> + *   modification, are permitted provided that the following conditions
> + *   are met:
> + *
> + *     * Redistributions of source code must retain the above copyright
> + *       notice, this list of conditions and the following disclaimer.
> + *     * Redistributions in binary form must reproduce the above copyright
> + *       notice, this list of conditions and the following disclaimer in
> + *       the documentation and/or other materials provided with the
> + *       distribution.
> + *     * Neither the name of Intel Corporation nor the names of its
> + *       contributors may be used to endorse or promote products derived
> + *       from this software without specific prior written permission.
> + *
> + *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
> CONTRIBUTORS
> + *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
> + *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
> FITNESS FOR
> + *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
> COPYRIGHT
> + *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
> INCIDENTAL,
> + *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> NOT
> + *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
> OF USE,
> + *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
> ON ANY
> + *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
> THE USE
> + *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
> DAMAGE.
> + */
> +
> +#ifndef _VIRTIO_NET_H_
> +#define _VIRTIO_NET_H_
> +
> +#include <stdint.h>
> +#include <linux/virtio_ring.h>
> +#include <linux/virtio_net.h>
> +#include <sys/eventfd.h>
> +
> +#include <rte_memory.h>
> +#include <rte_mempool.h>
> +#include <rte_mbuf.h>
> +
> +#define VIRTIO_DEV_RUNNING 1  /**< Used to indicate that the device is
> running on a data core. */
> +#define VIRTIO_DEV_STOPPED -1 /**< Backend value set by guest. */
> +
> +/* Enum for virtqueue management. */
> +enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
> +
> +/**
> + * Structure contains variables relevant to RX/TX virtqueues.
> + */
> +struct vhost_virtqueue {
> +	struct vring_desc    *desc;             /**< descriptor ring. */
> +	struct vring_avail   *avail;            /**< available ring. */
> +	struct vring_used    *used;             /**< used ring. */
> +	uint32_t             size;              /**< Size of descriptor ring. */
> +	uint32_t             backend;           /**< Backend value to determine if
> device should be started/stopped. */
> +	uint16_t             vhost_hlen;        /**< Vhost header length (varies
> depending on RX merge buffers. */
> +	volatile uint16_t    last_used_idx;     /**< Last index used on the available
> ring. */
> +	volatile uint16_t    last_used_idx_res; /**< Used for multiple devices
> reserving buffers. */
> +	eventfd_t            callfd;            /**< Currently unused as polling mode is
> enabled. */
> +	eventfd_t            kickfd;            /**< Used to notify the guest (trigger
> interrupt). */
> +} __rte_cache_aligned;
> +
> +/**
> + * Information relating to memory regions including offsets to
> + * addresses in QEMUs memory file.
> + */
> +struct virtio_memory_regions {
> +	uint64_t    guest_phys_address;     /**< Base guest physical address of
> region. */
> +	uint64_t    guest_phys_address_end; /**< End guest physical address of
> region. */
> +	uint64_t    memory_size;            /**< Size of region. */
> +	uint64_t    userspace_address;      /**< Base userspace address of region.
> */
> +	uint64_t    address_offset;         /**< Offset of region for address
> translation. */
> +};
> +
> +
> +/**
> + * Memory structure includes region and mapping information.
> + */
> +struct virtio_memory {
> +	uint64_t    base_address;    /**< Base QEMU userspace address of the
> memory file. */
> +	uint64_t    mapped_address;  /**< Mapped address of memory file base
> in our applications memory space. */
> +	uint64_t    mapped_size;     /**< Total size of memory file. */
> +	uint32_t    nregions;        /**< Number of memory regions. */
> +	struct virtio_memory_regions      regions[0]; /**< Memory region
> information. */
> +};
> +
> +/**
> + * Device structure contains all configuration information relating to the device.
> + */
> +struct virtio_net {
> +	struct vhost_virtqueue  *virtqueue[VIRTIO_QNUM]; /**< Contains all
> virtqueue information. */
> +	struct virtio_memory    *mem;                    /**< QEMU memory and
> memory region information. */
> +	uint64_t features;    /**< Negotiated feature set. */
> +	uint64_t device_fh;   /**< Device identifier. */
> +	uint32_t flags;       /**< Device flags. Only used to check if device is
> running on data core. */
> +	void     *priv;
> +} __rte_cache_aligned;
> +
> +/**
> + * Device operations to add/remove device.
> + */
> +struct virtio_net_device_ops {
> +	int (*new_device)(struct virtio_net *); /**< Add device. */
> +	void (*destroy_device)(struct virtio_net *); /**< Remove device. */
> +};
> +
> +
> +static inline uint16_t __attribute__((always_inline))
> +rte_vring_available_entries(struct virtio_net *dev, uint16_t queue_id)
> +{
> +	struct vhost_virtqueue *vq = dev->virtqueue[queue_id];
> +	return *(volatile uint16_t *)&vq->avail->idx - vq->last_used_idx_res;
> +}
> +
> +/**
> + * Function to convert guest physical addresses to vhost virtual addresses.
> + * This is used to convert guest virtio buffer addresses.
> + */
> +static inline uint64_t __attribute__((always_inline))
> +gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
> +{
> +	struct virtio_memory_regions *region;
> +	uint32_t regionidx;
> +	uint64_t vhost_va = 0;
> +
> +	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
> +		region = &dev->mem->regions[regionidx];
> +		if ((guest_pa >= region->guest_phys_address) &&
> +			(guest_pa <= region->guest_phys_address_end)) {
> +			vhost_va = region->address_offset + guest_pa;
> +			break;
> +		}
> +	}
> +	return vhost_va;
> +}
> +
> +/**
> + *  Disable features in feature_mask. Returns 0 on success.
> + */
> +int rte_vhost_feature_disable(uint64_t feature_mask);
> +
> +/**
> + *  Enable features in feature_mask. Returns 0 on success.
> + */
> +int rte_vhost_feature_enable(uint64_t feature_mask);
> +
> +/* Returns currently supported vhost features */
> +uint64_t rte_vhost_feature_get(void);
> +
> +int rte_vhost_enable_guest_notification(struct virtio_net *dev, uint16_t
> queue_id, int enable);
> +
> +/* Register vhost driver. dev_name could be different for multiple instance
> support. */
> +int rte_vhost_driver_register(const char *dev_name);
> +
> +/* Register callbacks. */
> +int rte_vhost_driver_callback_register(struct virtio_net_device_ops const *
> const);
> +
> +int rte_vhost_driver_session_start(void);
> +
> +/**
> + * This function adds buffers to the virtio devices RX virtqueue. Buffers can
> + * be received from the physical port or from another virtual device. A packet
> + * count is returned to indicate the number of packets that were succesfully
> + * added to the RX queue.
> + * @param queue_id
> + *  virtio queue index in mq case
> + * @return
> + *  num of packets enqueued
> + */
> +uint32_t rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id,
> +	struct rte_mbuf **pkts, uint32_t count);
> +
> +/**
> + * This function gets guest buffers from the virtio device TX virtqueue,
> + * construct host mbufs, copies guest buffer content to host mbufs and
> + * store them in pkts to be processed.
> + * @param mbuf_pool
> + *  mbuf_pool where host mbuf is allocated.
> + * @param queue_id
> + *  virtio queue index in mq case.
> + * @return
> + *  num of packets dequeued
> + */
> +uint32_t rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id,
> +	struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint32_t
> count);
> +
> +#endif /* _VIRTIO_NET_H_ */
> diff --git a/lib/librte_vhost/vhost-net-cdev.c b/lib/librte_vhost/vhost-net-cdev.c
> new file mode 100644
> index 0000000..b65c67b
> --- /dev/null
> +++ b/lib/librte_vhost/vhost-net-cdev.c
> @@ -0,0 +1,363 @@
> +/*-
> + *   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 <errno.h>
> +#include <fuse/cuse_lowlevel.h>
> +#include <linux/limits.h>
> +#include <linux/vhost.h>
> +#include <stdint.h>
> +#include <string.h>
> +#include <unistd.h>
> +
> +#include <rte_ethdev.h>
> +#include <rte_log.h>
> +#include <rte_string_fns.h>
> +#include <rte_virtio_net.h>
> +
> +#include "vhost-net-cdev.h"
> +
> +#define FUSE_OPT_DUMMY    "\0\0"
> +#define FUSE_OPT_FORE     "-f\0\0"
> +#define FUSE_OPT_NOMULTI  "-s\0\0"
> +
> +static const uint32_t	default_major = 231;
> +static const uint32_t	default_minor = 1;
> +static const char	cuse_device_name[]	= "/dev/cuse";
> +static const char	default_cdev[] = "vhost-net";
> +
> +static struct fuse_session		*session;
> +static struct vhost_net_device_ops	const *ops;
> +
> +/**
> + * Returns vhost_device_ctx from given fuse_req_t. The index is populated later
> when
> + * the device is added to the device linked list.
> + */
> +static struct vhost_device_ctx
> +fuse_req_to_vhost_ctx(fuse_req_t req, struct fuse_file_info *fi)
> +{
> +	struct vhost_device_ctx ctx;
> +	struct fuse_ctx const *const req_ctx = fuse_req_ctx(req);
> +
> +	ctx.pid = req_ctx->pid;
> +	ctx.fh = fi->fh;
> +
> +	return ctx;
> +}
> +
> +/**
> + * When the device is created in QEMU it gets initialised here and added to the
> device linked list.
> + */
> +static void
> +vhost_net_open(fuse_req_t req, struct fuse_file_info *fi)
> +{
> +	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
> +	int err = 0;
> +
> +	err = ops->new_device(ctx);
> +	if (err == -1) {
> +		fuse_reply_err(req, EPERM);
> +		return;
> +	}
> +
> +	fi->fh = err;
> +
> +	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device configuration
> started\n", fi->fh);
> +	fuse_reply_open(req, fi);
> +}
> +
> +/*
> + * When QEMU is shutdown or killed the device gets released.
> + */
> +static void
> +vhost_net_release(fuse_req_t req, struct fuse_file_info *fi)
> +{
> +	int err = 0;
> +	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
> +
> +	ops->destroy_device(ctx);
> +	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device released\n",
> ctx.fh);
> +	fuse_reply_err(req, err);
> +}
> +
> +/*
> + * Boilerplate code for CUSE IOCTL
> + * Implicit arguments: ctx, req, result.
> + */
> +#define VHOST_IOCTL(func) do { \
> +	result = (func)(ctx);  \
> +	fuse_reply_ioctl(req, result, NULL, 0);	 \
> +} while (0)
> +
> +/*
> + * Boilerplate IOCTL RETRY
> + * Implicit arguments: req.
> + */
> +#define VHOST_IOCTL_RETRY(size_r, size_w) do { \
> +	struct iovec iov_r = { arg, (size_r) }; \
> +	struct iovec iov_w = { arg, (size_w) }; \
> +	fuse_reply_ioctl_retry(req, &iov_r, (size_r) ? 1 : 0, &iov_w, (size_w) ? 1 :
> 0); \
> +} while (0)
> 
> 	\
> +
> +/*
> + * Boilerplate code for CUSE Read IOCTL
> + * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
> + */
> +#define VHOST_IOCTL_R(type, var, func) do {             \
> +	if (!in_bufsz) {                                \
> +		VHOST_IOCTL_RETRY(sizeof(type), 0);     \
> +	} else {                                        \
> +		(var) = *(const type*)in_buf;          \
> +		result = func(ctx, &(var));             \
> +		fuse_reply_ioctl(req, result, NULL, 0); \
> +	}                                               \
> +} while (0)
> +
> +/*
> + * Boilerplate code for CUSE Write IOCTL
> + * Implicit arguments: ctx, req, result, out_bufsz.
> + */
> +#define	VHOST_IOCTL_W(type, var, func) do {              \
> +	if (!out_bufsz) {                                \
> +		VHOST_IOCTL_RETRY(0, sizeof(type));      \
> +	} else {                                         \
> +		result = (func)(ctx, &(var));            \
> +		fuse_reply_ioctl(req, result, &(var), sizeof(type)); \
> +	} \
> +} while (0)
> +
> +/*
> + * Boilerplate code for CUSE Read/Write IOCTL
> + * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
> + */
> +#define VHOST_IOCTL_RW(type1, var1, type2, var2, func) do {      \
> +	if (!in_bufsz) {                                         \
> +		VHOST_IOCTL_RETRY(sizeof(type1), sizeof(type2)); \
> +	} else {                                                 \
> +		(var1) = *(const type1*) (in_buf);              \
> +		result = (func)(ctx, (var1), &(var2));           \
> +		fuse_reply_ioctl(req, result, &(var2), sizeof(type2));  \
> +	} \
> +} while (0)
> +
> +/**
> + * The IOCTLs are handled using CUSE/FUSE in userspace. Depending on
> + * the type of IOCTL a buffer is requested to read or to write. This
> + * request is handled by FUSE and the buffer is then given to CUSE.
> + */
> +static void
> +vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
> +		struct fuse_file_info *fi, __rte_unused unsigned flags,
> +		const void *in_buf, size_t in_bufsz, size_t out_bufsz)
> +{
> +	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
> +	struct vhost_vring_file file;
> +	struct vhost_vring_state state;
> +	struct vhost_vring_addr addr;
> +	uint64_t features;
> +	uint32_t index;
> +	int result = 0;
> +
> +	switch (cmd) {
> +
> +	case VHOST_NET_SET_BACKEND:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_NET_SET_BACKEND\n", ctx.fh);
> +		VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_backend);
> +		break;
> +
> +	case VHOST_GET_FEATURES:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_GET_FEATURES\n", ctx.fh);
> +		VHOST_IOCTL_W(uint64_t, features, ops->get_features);
> +		break;
> +
> +	case VHOST_SET_FEATURES:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_SET_FEATURES\n", ctx.fh);
> +		VHOST_IOCTL_R(uint64_t, features, ops->set_features);
> +		break;
> +
> +	case VHOST_RESET_OWNER:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_RESET_OWNER\n", ctx.fh);
> +		VHOST_IOCTL(ops->reset_owner);
> +		break;
> +
> +	case VHOST_SET_OWNER:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_SET_OWNER\n", ctx.fh);
> +		VHOST_IOCTL(ops->set_owner);
> +		break;
> +
> +	case VHOST_SET_MEM_TABLE:
> +		/*TODO fix race condition.*/
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_SET_MEM_TABLE\n", ctx.fh);
> +		static struct vhost_memory mem_temp;
> +
> +		switch (in_bufsz) {
> +		case 0:
> +			VHOST_IOCTL_RETRY(sizeof(struct vhost_memory), 0);
> +			break;
> +
> +		case sizeof(struct vhost_memory):
> +			mem_temp = *(const struct vhost_memory *) in_buf;
> +
> +			if (mem_temp.nregions > 0) {
> +				VHOST_IOCTL_RETRY(sizeof(struct
> vhost_memory) + (sizeof(struct vhost_memory_region) * mem_temp.nregions),
> 0);
> +			} else {
> +				result = -1;
> +				fuse_reply_ioctl(req, result, NULL, 0);
> +			}
> +			break;
> +
> +		default:
> +			result = ops->set_mem_table(ctx, in_buf,
> mem_temp.nregions);
> +			if (result)
> +				fuse_reply_err(req, EINVAL);
> +			else
> +				fuse_reply_ioctl(req, result, NULL, 0);
> +
> +		}
> +
> +		break;
> +
> +	case VHOST_SET_VRING_NUM:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_SET_VRING_NUM\n", ctx.fh);
> +		VHOST_IOCTL_R(struct vhost_vring_state, state, ops-
> >set_vring_num);
> +		break;
> +
> +	case VHOST_SET_VRING_BASE:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_SET_VRING_BASE\n", ctx.fh);
> +		VHOST_IOCTL_R(struct vhost_vring_state, state, ops-
> >set_vring_base);
> +		break;
> +
> +	case VHOST_GET_VRING_BASE:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_GET_VRING_BASE\n", ctx.fh);
> +		VHOST_IOCTL_RW(uint32_t, index, struct vhost_vring_state,
> state, ops->get_vring_base);
> +		break;
> +
> +	case VHOST_SET_VRING_ADDR:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_SET_VRING_ADDR\n", ctx.fh);
> +		VHOST_IOCTL_R(struct vhost_vring_addr, addr, ops-
> >set_vring_addr);
> +		break;
> +
> +	case VHOST_SET_VRING_KICK:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_SET_VRING_KICK\n", ctx.fh);
> +		VHOST_IOCTL_R(struct vhost_vring_file, file, ops-
> >set_vring_kick);
> +		break;
> +
> +	case VHOST_SET_VRING_CALL:
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL:
> VHOST_SET_VRING_CALL\n", ctx.fh);
> +		VHOST_IOCTL_R(struct vhost_vring_file, file, ops-
> >set_vring_call);
> +		break;
> +
> +	default:
> +		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") IOCTL: DOESN
> NOT EXIST\n", ctx.fh);
> +		result = -1;
> +		fuse_reply_ioctl(req, result, NULL, 0);
> +	}
> +
> +	if (result < 0)
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: FAIL\n",
> ctx.fh);
> +	else
> +		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: SUCCESS\n",
> ctx.fh);
> +}
> +
> +/**
> + * Structure handling open, release and ioctl function pointers is populated.
> + */
> +static const struct cuse_lowlevel_ops vhost_net_ops = {
> +	.open		= vhost_net_open,
> +	.release	= vhost_net_release,
> +	.ioctl		= vhost_net_ioctl,
> +};
> +
> +/**
> + * cuse_info is populated and used to register the cuse device.
> vhost_net_device_ops are
> + * also passed when the device is registered in main.c.
> + */
> +int
> +rte_vhost_driver_register(const char *dev_name)
> +{
> +	struct cuse_info cuse_info;
> +	char device_name[PATH_MAX] = "";
> +	char char_device_name[PATH_MAX] = "";
> +	const char *device_argv[] = { device_name };
> +
> +	char fuse_opt_dummy[] = FUSE_OPT_DUMMY;
> +	char fuse_opt_fore[] = FUSE_OPT_FORE;
> +	char fuse_opt_nomulti[] = FUSE_OPT_NOMULTI;
> +	char *fuse_argv[] = {fuse_opt_dummy, fuse_opt_fore,
> fuse_opt_nomulti};
> +
> +	if (access(cuse_device_name, R_OK | W_OK) < 0) {
> +		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s can't be
> accessed, maybe not exist\n", cuse_device_name);
> +		return -1;
> +	}
> +
> +	/*
> +	 * The device name is created. This is passed to QEMU so that it can
> register
> +	 * the device with our application. The dev_name allows us to have
> multiple instances
> +	 * of userspace vhost which we can then add devices to separately.
> +	 */
> +	snprintf(device_name, PATH_MAX, "DEVNAME=%s", dev_name);
> +	snprintf(char_device_name, PATH_MAX, "/dev/%s", dev_name);
> +
> +	/* Check if device already exists. */
> +	if (access(char_device_name, F_OK) != -1) {
> +		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s already
> exists\n", char_device_name);
> +		return -1;
> +	}
> +
> +	memset(&cuse_info, 0, sizeof(cuse_info));
> +	cuse_info.dev_major = default_major;
> +	cuse_info.dev_minor = default_minor;
> +	cuse_info.dev_info_argc = 1;
> +	cuse_info.dev_info_argv = device_argv;
> +	cuse_info.flags = CUSE_UNRESTRICTED_IOCTL;
> +
> +	ops = get_virtio_net_callbacks();
> +
> +	session = cuse_lowlevel_setup(3, fuse_argv,
> +				&cuse_info, &vhost_net_ops, 0, NULL);
> +	if (session == NULL)
> +		return -1;
> +
> +	return 0;
> +}
> +
> +
> +/**
> + * The CUSE session is launched allowing the application to receive open,
> release and ioctl calls.
> + */
> +int
> +rte_vhost_driver_session_start(void)
> +{
> +	fuse_session_loop(session);
> +
> +	return 0;
> +}
> diff --git a/lib/librte_vhost/vhost-net-cdev.h b/lib/librte_vhost/vhost-net-cdev.h
> new file mode 100644
> index 0000000..01a1b58
> --- /dev/null
> +++ b/lib/librte_vhost/vhost-net-cdev.h
> @@ -0,0 +1,109 @@
> +/*-
> + *   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 <stdint.h>
> +#include <stdio.h>
> +#include <sys/types.h>
> +#include <unistd.h>
> +#include <linux/vhost.h>
> +
> +#include <rte_log.h>
> +
> +/* Macros for printing using RTE_LOG */
> +#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
> +#define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER1
> +
> +#ifdef RTE_LIBRTE_VHOST_DEBUG
> +#define VHOST_MAX_PRINT_BUFF 6072
> +#define LOG_LEVEL RTE_LOG_DEBUG
> +#define LOG_DEBUG(log_type, fmt, args...) RTE_LOG(DEBUG, log_type, fmt,
> ##args)
> +#define VHOST_PRINT_PACKET(device, addr, size, header) do { \
> +	char *pkt_addr = (char *)(addr); \
> +	unsigned int index; \
> +	char packet[VHOST_MAX_PRINT_BUFF]; \
> +	\
> +	if ((header)) \
> +		snprintf(packet, VHOST_MAX_PRINT_BUFF, "(%"PRIu64")
> Header size %d: ", (device->device_fh), (size)); \
> +	else \
> +		snprintf(packet, VHOST_MAX_PRINT_BUFF, "(%"PRIu64") Packet
> size %d: ", (device->device_fh), (size)); \
> +	for (index = 0; index < (size); index++) { \
> +		snprintf(packet + strnlen(packet, VHOST_MAX_PRINT_BUFF),
> VHOST_MAX_PRINT_BUFF - strnlen(packet, VHOST_MAX_PRINT_BUFF), \
> +			"%02hhx ", pkt_addr[index]); \
> +	} \
> +	snprintf(packet + strnlen(packet, VHOST_MAX_PRINT_BUFF),
> VHOST_MAX_PRINT_BUFF - strnlen(packet, VHOST_MAX_PRINT_BUFF), "\n"); \
> +	\
> +	LOG_DEBUG(VHOST_DATA, "%s", packet); \
> +} while (0)
> +#else
> +#define LOG_LEVEL RTE_LOG_INFO
> +#define LOG_DEBUG(log_type, fmt, args...) do {} while (0)
> +#define VHOST_PRINT_PACKET(device, addr, size, header) do {} while (0)
> +#endif
> +
> +/**
> + * Structure used to identify device context.
> + */
> +struct vhost_device_ctx {
> +	pid_t    pid; /**< PID of process calling the IOCTL. */
> +	uint64_t fh;  /**< Populated with fi->fh to track the device index. */
> +};
> +
> +/**
> + * Structure contains function pointers to be defined in virtio-net.c. These
> + * functions are called in CUSE context and are used to configure devices.
> + */
> +struct vhost_net_device_ops {
> +	int (*new_device)(struct vhost_device_ctx);
> +	void (*destroy_device)(struct vhost_device_ctx);
> +
> +	int (*get_features)(struct vhost_device_ctx, uint64_t *);
> +	int (*set_features)(struct vhost_device_ctx, uint64_t *);
> +
> +	int (*set_mem_table)(struct vhost_device_ctx, const void *, uint32_t);
> +
> +	int (*set_vring_num)(struct vhost_device_ctx, struct vhost_vring_state
> *);
> +	int (*set_vring_addr)(struct vhost_device_ctx, struct vhost_vring_addr *);
> +	int (*set_vring_base)(struct vhost_device_ctx, struct vhost_vring_state
> *);
> +	int (*get_vring_base)(struct vhost_device_ctx, uint32_t, struct
> vhost_vring_state *);
> +
> +	int (*set_vring_kick)(struct vhost_device_ctx, struct vhost_vring_file *);
> +	int (*set_vring_call)(struct vhost_device_ctx, struct vhost_vring_file *);
> +
> +	int (*set_backend)(struct vhost_device_ctx, struct vhost_vring_file *);
> +
> +	int (*set_owner)(struct vhost_device_ctx);
> +	int (*reset_owner)(struct vhost_device_ctx);
> +};
> +
> +
> +struct vhost_net_device_ops const *get_virtio_net_callbacks(void);
> diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
> new file mode 100644
> index 0000000..d25457b
> --- /dev/null
> +++ b/lib/librte_vhost/vhost_rxtx.c
> @@ -0,0 +1,292 @@
> +/*-
> + *   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 <stdint.h>
> +#include <linux/virtio_net.h>
> +
> +#include <rte_mbuf.h>
> +#include <rte_memcpy.h>
> +#include <rte_virtio_net.h>
> +
> +#include "vhost-net-cdev.h"
> +
> +#define VHOST_MAX_PKT_BURST 64
> +#define VHOST_MAX_MRG_PKT_BURST 64
> +
> +
> +uint32_t
> +rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct
> rte_mbuf **pkts, uint32_t count)
> +{
> +	struct vhost_virtqueue *vq;
> +	struct vring_desc *desc;
> +	struct rte_mbuf *buff;
> +	/* The virtio_hdr is initialised to 0. */
> +	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0};
> +	uint64_t buff_addr = 0;
> +	uint64_t buff_hdr_addr = 0;
> +	uint32_t head[VHOST_MAX_PKT_BURST], packet_len = 0;
> +	uint32_t head_idx, packet_success = 0;
> +	uint32_t mergeable, mrg_count = 0;
> +	uint16_t avail_idx, res_cur_idx;
> +	uint16_t res_base_idx, res_end_idx;
> +	uint16_t free_entries;
> +	uint8_t success = 0;
> +
> +	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") %s()\n", dev->device_fh,
> __func__);
> +	if (unlikely(queue_id != VIRTIO_RXQ)) {
> +		LOG_DEBUG(VHOST_DATA, "mq isn't supported in this
> version.\n");
> +		return 0;
> +	}
> +
> +	vq = dev->virtqueue[VIRTIO_RXQ];
> +	count = (count > VHOST_MAX_PKT_BURST) ? VHOST_MAX_PKT_BURST :
> count;
> +	/* As many data cores may want access to available buffers, they need
> to be reserved. */
> +	do {
> +		res_base_idx = vq->last_used_idx_res;
> +		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
> +
> +		free_entries = (avail_idx - res_base_idx);
> +		/*check that we have enough buffers*/
> +		if (unlikely(count > free_entries))
> +			count = free_entries;
> +
> +		if (count == 0)
> +			return 0;
> +
> +		res_end_idx = res_base_idx + count;
> +		/* vq->last_used_idx_res is atomically updated. */
> +		/* TODO: Allow to disable cmpset if no concurrency in
> application */
> +		success = rte_atomic16_cmpset(&vq->last_used_idx_res,
> +				res_base_idx, res_end_idx);
> +		/* If there is contention here and failed, try again. */
> +	} while (unlikely(success == 0));
> +	res_cur_idx = res_base_idx;
> +	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End
> Index %d\n",
> +			dev->device_fh,
> +			res_cur_idx, res_end_idx);
> +
> +	/* Prefetch available ring to retrieve indexes. */
> +	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
> +
> +	/* Check if the VIRTIO_NET_F_MRG_RXBUF feature is enabled. */
> +	mergeable = dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
> +
> +	/* Retrieve all of the head indexes first to avoid caching issues. */
> +	for (head_idx = 0; head_idx < count; head_idx++)
> +		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) &
> (vq->size - 1)];
> +
> +	/*Prefetch descriptor index. */
> +	rte_prefetch0(&vq->desc[head[packet_success]]);
> +
> +	while (res_cur_idx != res_end_idx) {
> +		/* Get descriptor from available ring */
> +		desc = &vq->desc[head[packet_success]];
> +
> +		buff = pkts[packet_success];
> +
> +		/* Convert from gpa to vva (guest physical addr -> vhost virtual
> addr) */
> +		buff_addr = gpa_to_vva(dev, desc->addr);
> +		/* Prefetch buffer address. */
> +		rte_prefetch0((void *)(uintptr_t)buff_addr);
> +
> +		if (mergeable && (mrg_count != 0)) {
> +			desc->len = packet_len = rte_pktmbuf_data_len(buff);
> +		} else {
> +			/* Copy virtio_hdr to packet and increment buffer
> address */
> +			buff_hdr_addr = buff_addr;
> +			packet_len = rte_pktmbuf_data_len(buff) + vq-
> >vhost_hlen;
> +
> +			/*
> +			 * If the descriptors are chained the header and data
> are placed in
> +			 * separate buffers.
> +			 */
> +			if (desc->flags & VRING_DESC_F_NEXT) {
> +				desc->len = vq->vhost_hlen;
> +				desc = &vq->desc[desc->next];
> +				/* Buffer address translation. */
> +				buff_addr = gpa_to_vva(dev, desc->addr);
> +				desc->len = rte_pktmbuf_data_len(buff);
> +			} else {
> +				buff_addr += vq->vhost_hlen;
> +				desc->len = packet_len;
> +			}
> +		}
> +
> +		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_addr,
> rte_pktmbuf_data_len(buff), 0);
> +
> +		/* Update used ring with desc information */
> +		vq->used->ring[res_cur_idx & (vq->size - 1)].id =
> head[packet_success];
> +		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
> +
> +		/* Copy mbuf data to buffer */
> +		/* TODO fixme for sg mbuf and the case that desc couldn't hold
> the mbuf data */
> +		rte_memcpy((void *)(uintptr_t)buff_addr, (const void *)buff-
> >pkt.data, rte_pktmbuf_data_len(buff));
> +
> +		res_cur_idx++;
> +		packet_success++;
> +
> +		/* If mergeable is disabled then a header is required per buffer.
> */
> +		if (!mergeable) {
> +			rte_memcpy((void *)(uintptr_t)buff_hdr_addr, (const
> void *)&virtio_hdr, vq->vhost_hlen);
> +			VHOST_PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr,
> vq->vhost_hlen, 1);
> +		} else {
> +			mrg_count++;
> +			/* Merge buffer can only handle so many buffers at a
> time. Tell the guest if this limit is reached. */
> +			if ((mrg_count == VHOST_MAX_MRG_PKT_BURST) ||
> (res_cur_idx == res_end_idx)) {
> +				virtio_hdr.num_buffers = mrg_count;
> +				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX:
> Num merge buffers %d\n", dev->device_fh, virtio_hdr.num_buffers);
> +				rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
> (const void *)&virtio_hdr, vq->vhost_hlen);
> +				VHOST_PRINT_PACKET(dev,
> (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
> +				mrg_count = 0;
> +			}
> +		}
> +		if (res_cur_idx < res_end_idx) {
> +			/* Prefetch descriptor index. */
> +			rte_prefetch0(&vq->desc[head[packet_success]]);
> +		}
> +	}
> +
> +	rte_compiler_barrier();
> +
> +	/* Wait until it's our turn to add our buffer to the used ring. */
> +	while (unlikely(vq->last_used_idx != res_base_idx))
> +		rte_pause();
> +
> +	*(volatile uint16_t *)&vq->used->idx += count;
> +	vq->last_used_idx = res_end_idx;
> +
> +	/* Kick the guest if necessary. */
> +	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
> +		eventfd_write((int)vq->kickfd, 1);
> +	return count;
> +}
> +
> +
> +uint32_t
> +rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct
> rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint32_t count)
> +{
> +	struct rte_mbuf *mbuf;
> +	struct vhost_virtqueue *vq;
> +	struct vring_desc *desc;
> +	uint64_t buff_addr = 0;
> +	uint32_t head[VHOST_MAX_PKT_BURST];
> +	uint32_t used_idx;
> +	uint32_t i;
> +	uint16_t free_entries, packet_success = 0;
> +	uint16_t avail_idx;
> +
> +	if (unlikely(queue_id != VIRTIO_TXQ)) {
> +		LOG_DEBUG(VHOST_DATA, "mq isn't supported in this
> version.\n");
> +		return 0;
> +	}
> +
> +	vq = dev->virtqueue[VIRTIO_TXQ];
> +	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
> +
> +	/* If there are no available buffers then return. */
> +	if (vq->last_used_idx == avail_idx)
> +		return 0;
> +
> +	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev-
> >device_fh);
> +
> +	/* Prefetch available ring to retrieve head indexes. */
> +	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
> +
> +	/*get the number of free entries in the ring*/
> +	free_entries = (avail_idx - vq->last_used_idx);
> +
> +	if (free_entries > count)
> +		free_entries = count;
> +	/* Limit to MAX_PKT_BURST. */
> +	if (free_entries > VHOST_MAX_PKT_BURST)
> +		free_entries = VHOST_MAX_PKT_BURST;
> +
> +	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev-
> >device_fh, free_entries);
> +	/* Retrieve all of the head indexes first to avoid caching issues. */
> +	for (i = 0; i < free_entries; i++)
> +		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
> +
> +	/* Prefetch descriptor index. */
> +	rte_prefetch0(&vq->desc[head[packet_success]]);
> +	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
> +
> +	while (packet_success < free_entries) {
> +		desc = &vq->desc[head[packet_success]];
> +
> +		/* Discard first buffer as it is the virtio header */
> +		desc = &vq->desc[desc->next];
> +
> +		/* Buffer address translation. */
> +		buff_addr = gpa_to_vva(dev, desc->addr);
> +		/* Prefetch buffer address. */
> +		rte_prefetch0((void *)(uintptr_t)buff_addr);
> +
> +		used_idx = vq->last_used_idx & (vq->size - 1);
> +
> +		if (packet_success < (free_entries - 1)) {
> +			/* Prefetch descriptor index. */
> +			rte_prefetch0(&vq->desc[head[packet_success+1]]);
> +			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq-
> >size - 1)]);
> +		}
> +
> +		/* Update used index buffer information. */
> +		vq->used->ring[used_idx].id = head[packet_success];
> +		vq->used->ring[used_idx].len = 0;
> +
> +		mbuf = rte_pktmbuf_alloc(mbuf_pool);
> +		if (unlikely(mbuf == NULL)) {
> +			RTE_LOG(ERR, VHOST_DATA, "Failed to allocate
> memory for mbuf.\n");
> +			return packet_success;
> +		}
> +		mbuf->pkt.data_len = desc->len;
> +		mbuf->pkt.pkt_len  = mbuf->pkt.data_len;
> +
> +		rte_memcpy((void *) mbuf->pkt.data,
> +			(const void *) buff_addr, mbuf->pkt.data_len);
> +
> +		pkts[packet_success] = mbuf;
> +
> +		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
> +
> +		vq->last_used_idx++;
> +		packet_success++;
> +	}
> +
> +	rte_compiler_barrier();
> +	vq->used->idx += packet_success;
> +	/* Kick guest if required. */
> +	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
> +		eventfd_write((int)vq->kickfd, 1);
> +
> +	return packet_success;
> +}
> diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
> new file mode 100644
> index 0000000..80e3b8c
> --- /dev/null
> +++ b/lib/librte_vhost/virtio-net.c
> @@ -0,0 +1,1002 @@
> +/*-
> + *   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 <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 entry on linked list. */
> +};
> +
> +static const char eventfd_cdev[] = "/dev/eventfd-link";
> +
> +/* device ops to add/remove device to data core. */
> +static struct virtio_net_device_ops const *notify_ops;
> +/* Root address of the linked list in the configuration core. */
> +static struct virtio_net_config_ll *ll_root;
> +
> +/* Features supported by this library. */
> +#define VHOST_SUPPORTED_FEATURES (1ULL << VIRTIO_NET_F_MRG_RXBUF)
> +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];
> +	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 in to 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);
> +		realpath(memfile, resolved_path);
> +		if (resolved_path == NULL) {
> +			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, (long long unsigned)mem-
> >mapped_size, map);
> +
> +	return 0;
> +}
> +
> +/**
> + *  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;
> +}
> +
> +/**
> + * 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);
> +}
> +
> +/**
> + * 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 a matching entry is found in the linked list, return the device in that
> entry. */
> +	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;
> +	}
> +
> +}
> +
> +/**
> + * 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;
> +		}
> +	}
> +}
> +
> +
> +/**
> + * 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 virtqueue_rx.\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 virtqueue_tx.\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);
> +			/*TODO return here? */
> +		} 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 set of 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 TX queue is 1, RX queue 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 TX queue is 1, RX queue 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
> descriptor 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
> available 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 TX queue is 1, RX queue 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 TX queue is 1, RX queue 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
> in
> + * to 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 TX queue is 1, RX queue 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 in
> + * to 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 TX queue is 1, RX queue 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;
> +}
> +
> +/**
> + * 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 TX queue is 1, RX queue 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;
> +}
> +
> +/**
> + * 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;
> +}
> --
> 1.8.1.4



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