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SubjectRe: [RFC v4 3/3] vhost: introduce mdev based hardware backend
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On 2019/9/17 上午9:02, Tiwei Bie wrote:
> More details about this patch can be found from the cover
> letter for now. Only compile test has been done for now.
>
> Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> ---
> drivers/vhost/Kconfig | 9 +
> drivers/vhost/Makefile | 3 +
> drivers/vhost/mdev.c | 462 +++++++++++++++++++++++++++++++
> drivers/vhost/vhost.c | 39 ++-
> drivers/vhost/vhost.h | 6 +
> include/uapi/linux/vhost.h | 10 +
> include/uapi/linux/vhost_types.h | 5 +
> 7 files changed, 528 insertions(+), 6 deletions(-)
> create mode 100644 drivers/vhost/mdev.c
>
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index 3d03ccbd1adc..ef9783156d2e 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -34,6 +34,15 @@ config VHOST_VSOCK
> To compile this driver as a module, choose M here: the module will be called
> vhost_vsock.
>
> +config VHOST_MDEV
> + tristate "Mediated device based hardware vhost accelerator"
> + depends on EVENTFD && VFIO && VFIO_MDEV
> + select VHOST
> + default n
> + ---help---
> + Say Y here to enable the vhost_mdev module
> + for use with hardware vhost accelerators
> +
> config VHOST
> tristate
> ---help---
> diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile
> index 6c6df24f770c..ad9c0f8c6d8c 100644
> --- a/drivers/vhost/Makefile
> +++ b/drivers/vhost/Makefile
> @@ -10,4 +10,7 @@ vhost_vsock-y := vsock.o
>
> obj-$(CONFIG_VHOST_RING) += vringh.o
>
> +obj-$(CONFIG_VHOST_MDEV) += vhost_mdev.o
> +vhost_mdev-y := mdev.o
> +
> obj-$(CONFIG_VHOST) += vhost.o
> diff --git a/drivers/vhost/mdev.c b/drivers/vhost/mdev.c
> new file mode 100644
> index 000000000000..8c6597aff45e
> --- /dev/null
> +++ b/drivers/vhost/mdev.c
> @@ -0,0 +1,462 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2018-2019 Intel Corporation.
> + */
> +
> +#include <linux/compat.h>
> +#include <linux/kernel.h>
> +#include <linux/miscdevice.h>
> +#include <linux/mdev.h>
> +#include <linux/module.h>
> +#include <linux/vfio.h>
> +#include <linux/vhost.h>
> +#include <linux/virtio_mdev.h>
> +
> +#include "vhost.h"
> +
> +struct vhost_mdev {
> + struct mutex mutex;
> + struct vhost_dev dev;
> + struct vhost_virtqueue *vqs;
> + int nvqs;
> + u64 state;
> + u64 features;
> + u64 acked_features;
> + struct vfio_group *vfio_group;
> + struct vfio_device *vfio_device;
> + struct mdev_device *mdev;
> +};
> +
> +/*
> + * XXX
> + * We assume virtio_mdev.ko exposes below symbols for now, as we
> + * don't have a proper way to access parent ops directly yet.
> + *
> + * virtio_mdev_readl()
> + * virtio_mdev_writel()
> + */
> +extern u32 virtio_mdev_readl(struct mdev_device *mdev, loff_t off);
> +extern void virtio_mdev_writel(struct mdev_device *mdev, loff_t off, u32 val);


Need to consider a better approach, I feel we should do it through some
kind of mdev driver instead of talk to mdev device directly.


> +
> +static u8 mdev_get_status(struct mdev_device *mdev)
> +{
> + return virtio_mdev_readl(mdev, VIRTIO_MDEV_STATUS);
> +}
> +
> +static void mdev_set_status(struct mdev_device *mdev, u8 status)
> +{
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_STATUS, status);
> +}
> +
> +static void mdev_add_status(struct mdev_device *mdev, u8 status)
> +{
> + status |= mdev_get_status(mdev);
> + mdev_set_status(mdev, status);
> +}
> +
> +static void mdev_reset(struct mdev_device *mdev)
> +{
> + mdev_set_status(mdev, 0);
> +}
> +
> +static void handle_vq_kick(struct vhost_work *work)
> +{
> + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
> + poll.work);
> + struct vhost_mdev *m = container_of(vq->dev, struct vhost_mdev, dev);
> +
> + virtio_mdev_writel(m->mdev, VIRTIO_MDEV_QUEUE_NOTIFY, vq - m->vqs);
> +}
> +
> +static long vhost_mdev_start_backend(struct vhost_mdev *m)
> +{
> + struct mdev_device *mdev = m->mdev;
> + u64 features = m->acked_features;
> + u64 addr;
> + struct vhost_virtqueue *vq;
> + int queue_id;
> +
> + features |= 1ULL << VIRTIO_F_IOMMU_PLATFORM;


Is it better to get this feature from backend?


> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_DRIVER_FEATURES_SEL, 1);
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_DRIVER_FEATURES,
> + (u32)(features >> 32));
> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_DRIVER_FEATURES_SEL, 0);
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_DRIVER_FEATURES,
> + (u32)features);
> +
> + mdev_add_status(mdev, VIRTIO_CONFIG_S_FEATURES_OK);
> + if (!(mdev_get_status(mdev) & VIRTIO_CONFIG_S_FEATURES_OK))
> + return -ENODEV;
> +
> + for (queue_id = 0; queue_id < m->nvqs; queue_id++) {
> + vq = &m->vqs[queue_id];
> +
> + if (!vq->desc || !vq->avail || !vq->used)
> + break;
> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_NUM, vq->num);
> +
> + if (!vhost_translate_ring_addr(vq, (u64)vq->desc,
> + vhost_get_desc_size(vq, vq->num),
> + &addr))
> + return -EINVAL;


Interesting, any reason for doing such kinds of translation to HVA? I
believe the add should already an IOVA that has been map by VFIO.


> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_DESC_LOW, addr);
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_DESC_HIGH,
> + (addr >> 32));
> +
> + if (!vhost_translate_ring_addr(vq, (u64)vq->avail,
> + vhost_get_avail_size(vq, vq->num),
> + &addr))
> + return -EINVAL;
> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_AVAIL_LOW, addr);
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_AVAIL_HIGH,
> + (addr >> 32));
> +
> + if (!vhost_translate_ring_addr(vq, (u64)vq->used,
> + vhost_get_used_size(vq, vq->num),
> + &addr))
> + return -EINVAL;
> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_USED_LOW, addr);
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_USED_HIGH,
> + (addr >> 32));
> +
> + // XXX: we need to support set_vring_base


I'm working on V2 that support this API.


> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_READY, 1);
> + }
> +
> + // XXX: we need to setup interrupt as well


V2 will have a better interrupt API like some kind of callback. It could
be as simple as a wrapper of eventfd_signal().


> +
> + mdev_add_status(mdev, VIRTIO_CONFIG_S_DRIVER_OK);
> + return 0;
> +}
> +
> +static long vhost_mdev_stop_backend(struct vhost_mdev *m)
> +{
> + struct mdev_device *mdev = m->mdev;
> +
> + mdev_reset(mdev);
> + mdev_add_status(mdev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
> + mdev_add_status(mdev, VIRTIO_CONFIG_S_DRIVER);
> + return 0;
> +}
> +
> +static long vhost_set_state(struct vhost_mdev *m, u64 __user *statep)
> +{
> + u64 state;
> + long r;
> +
> + if (copy_from_user(&state, statep, sizeof(state)))
> + return -EFAULT;
> +
> + if (state >= VHOST_MDEV_S_MAX)
> + return -EINVAL;
> +
> + if (m->state == state)
> + return 0;
> +
> + m->state = state;
> +
> + switch (m->state) {
> + case VHOST_MDEV_S_RUNNING:
> + r = vhost_mdev_start_backend(m);
> + break;
> + case VHOST_MDEV_S_STOPPED:
> + r = vhost_mdev_stop_backend(m);
> + break;
> + default:
> + r = -EINVAL;
> + break;
> + }
> +
> + return r;
> +}
> +
> +static long vhost_get_features(struct vhost_mdev *m, u64 __user *featurep)
> +{
> + if (copy_to_user(featurep, &m->features, sizeof(m->features)))
> + return -EFAULT;
> + return 0;
> +}
> +
> +static long vhost_set_features(struct vhost_mdev *m, u64 __user *featurep)
> +{
> + u64 features;
> +
> + if (copy_from_user(&features, featurep, sizeof(features)))
> + return -EFAULT;
> +
> + if (features & ~m->features)
> + return -EINVAL;
> +
> + m->acked_features = features;
> +
> + return 0;
> +}
> +
> +static long vhost_get_vring_base(struct vhost_mdev *m, void __user *argp)
> +{
> + struct vhost_virtqueue *vq;
> + u32 idx;
> + long r;
> +
> + r = get_user(idx, (u32 __user *)argp);
> + if (r < 0)
> + return r;
> + if (idx >= m->nvqs)
> + return -ENOBUFS;
> +
> + vq = &m->vqs[idx];
> +
> + // XXX: we need to support get_vring_base
> + //vq->last_avail_idx = virtio_mdev_readl(b->mdev, ...);
> +
> + return vhost_vring_ioctl(&m->dev, VHOST_GET_VRING_BASE, argp);
> +}
> +
> +static void vhost_mdev_release_backend(struct vhost_mdev *m)
> +{
> + if (!m->mdev)
> + return;
> +
> + if (m->state != VHOST_MDEV_S_STOPPED) {
> + m->state = VHOST_MDEV_S_STOPPED;
> + vhost_mdev_stop_backend(m);
> + }
> +
> + vhost_dev_stop(&m->dev);
> + vhost_dev_cleanup(&m->dev);
> +
> + kfree(m->dev.vqs);
> + kfree(m->vqs);
> +
> + vfio_device_put(m->vfio_device);
> + vfio_group_put_external_user(m->vfio_group);
> +
> + m->mdev = NULL;
> +}
> +
> +static long vhost_mdev_set_backend(struct vhost_mdev *m,
> + struct vhost_mdev_backend __user *argp)
> +{
> + struct vhost_mdev_backend backend;
> + struct mdev_device *mdev;
> + struct vhost_dev *dev;
> + struct vhost_virtqueue **vqs;
> + struct file *file;
> + struct vfio_device *device;
> + struct vfio_group *group;
> + unsigned long magic;
> + u64 features;
> + int i, nvqs;
> + long r;
> +
> + vhost_mdev_release_backend(m);
> +
> + if (copy_from_user(&backend, argp, sizeof(backend))) {
> + r = -EFAULT;
> + goto err;
> + }
> +
> + file = fget(backend.group_fd);
> + if (!file) {
> + r = -EBADF;
> + goto err;
> + }
> +
> + group = vfio_group_get_external_user(file);
> + fput(file);
> + if (IS_ERR(group)) {
> + r = PTR_ERR(group);
> + goto err;
> + }
> +
> + device = vfio_device_get_from_fd(group, backend.device_fd);
> + if (!IS_ERR(device)) {
> + r = PTR_ERR(device);
> + goto err_put_group;
> + }
> +
> + if (!vfio_device_ops_match(device, &vfio_mdev_dev_ops)) {
> + r = -EINVAL;
> + goto err_put_device;
> + }


It looks to me that we can avoid to expose vfio_mdev_dev_ops here.


> +
> + mdev = vfio_device_data(m->vfio_device);
> +
> + magic = virtio_mdev_readl(mdev, VIRTIO_MDEV_MAGIC_VALUE);
> + if (magic != ('v' | 'i' << 8 | 'r' << 16 | 't' << 24)) {
> + r = -ENODEV;
> + goto err_put_device;
> + }
> +
> + mdev_reset(mdev);
> + mdev_add_status(mdev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
> + mdev_add_status(mdev, VIRTIO_CONFIG_S_DRIVER);
> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_DEVICE_FEATURES_SEL, 1);
> + features = virtio_mdev_readl(mdev, VIRTIO_MDEV_DEVICE_FEATURES);
> + features <<= 32;
> +
> + virtio_mdev_writel(mdev, VIRTIO_MDEV_DEVICE_FEATURES_SEL, 0);
> + features |= virtio_mdev_readl(mdev, VIRTIO_MDEV_DEVICE_FEATURES);
> +
> + if (!(features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))) {
> + r = -EINVAL;
> + goto err_put_device;
> + }
> +
> + m->features = features;
> +
> + nvqs = virtio_mdev_readl(mdev, VIRTIO_MDEV_QUEUE_NUM_MAX);
> + m->nvqs = nvqs;
> +
> + m->vqs = kmalloc_array(nvqs, sizeof(struct vhost_virtqueue),
> + GFP_KERNEL);
> + if (!m->vqs) {
> + r = -ENOMEM;
> + goto err_put_device;
> + }
> +
> + vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
> + if (!vqs) {
> + r = -ENOMEM;
> + goto err_free_vqs;
> + }
> +
> + dev = &m->dev;
> + for (i = 0; i < nvqs; i++) {
> + vqs[i] = &m->vqs[i];
> + vqs[i]->handle_kick = handle_vq_kick;
> + }
> + vhost_dev_init(dev, vqs, nvqs, 0, 0, 0);
> +
> + m->vfio_group = group;
> + m->vfio_device = device;
> + m->mdev = mdev;
> +
> + return 0;
> +
> +err_free_vqs:
> + kfree(m->vqs);
> +err_put_device:
> + vfio_device_put(device);
> +err_put_group:
> + vfio_group_put_external_user(group);
> +err:
> + return r;
> +}
> +
> +static int vhost_mdev_open(struct inode *inode, struct file *f)
> +{
> + struct vhost_mdev *m;
> +
> + m = kzalloc(sizeof(*m), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
> + if (!m)
> + return -ENOMEM;
> +
> + mutex_init(&m->mutex);
> + f->private_data = m;
> +
> + return 0;
> +}
> +
> +static int vhost_mdev_release(struct inode *inode, struct file *f)
> +{
> + struct vhost_mdev *m = f->private_data;
> +
> + vhost_mdev_release_backend(m);
> + mutex_destroy(&m->mutex);
> + kfree(m);
> +
> + return 0;
> +}
> +
> +static long vhost_mdev_ioctl(struct file *f, unsigned int cmd,
> + unsigned long arg)
> +{
> + void __user *argp = (void __user *)arg;
> + struct vhost_mdev *m = f->private_data;
> + long r;
> +
> + mutex_lock(&m->mutex);
> +
> + if (cmd == VHOST_MDEV_SET_BACKEND) {
> + r = vhost_mdev_set_backend(m, argp);
> + goto done;
> + }
> +
> + if (!m->mdev) {
> + r = -EINVAL;
> + goto done;
> + }
> +
> + switch (cmd) {
> + case VHOST_MDEV_SET_STATE:
> + r = vhost_set_state(m, argp);
> + break;
> + case VHOST_GET_FEATURES:
> + r = vhost_get_features(m, argp);
> + break;
> + case VHOST_SET_FEATURES:
> + r = vhost_set_features(m, argp);
> + break;
> + case VHOST_GET_VRING_BASE:
> + r = vhost_get_vring_base(m, argp);
> + break;
> + default:
> + r = vhost_dev_ioctl(&m->dev, cmd, argp);
> + if (r == -ENOIOCTLCMD)
> + r = vhost_vring_ioctl(&m->dev, cmd, argp);
> + }
> +
> +done:
> + mutex_lock(&m->mutex);
> + return r;
> +}
> +
> +#ifdef CONFIG_COMPAT
> +static long vhost_mdev_compat_ioctl(struct file *f, unsigned int ioctl,
> + unsigned long arg)
> +{
> + return vhost_mdev_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
> +}
> +#endif
> +
> +static const struct file_operations vhost_mdev_fops = {
> + .owner = THIS_MODULE,
> + .release = vhost_mdev_release,
> + .unlocked_ioctl = vhost_mdev_ioctl,
> +#ifdef CONFIG_COMPAT
> + .compat_ioctl = vhost_mdev_compat_ioctl,
> +#endif
> + .open = vhost_mdev_open,
> + .llseek = noop_llseek,
> +};
> +
> +static struct miscdevice vhost_mdev_misc = {
> + .minor = MISC_DYNAMIC_MINOR,
> + .name = "vhost-mdev",
> + .fops = &vhost_mdev_fops,
> +};
> +
> +static int __init vhost_mdev_init(void)
> +{
> + return misc_register(&vhost_mdev_misc);
> +}
> +module_init(vhost_mdev_init);
> +
> +static void __exit vhost_mdev_exit(void)
> +{
> + misc_deregister(&vhost_mdev_misc);
> +}
> +module_exit(vhost_mdev_exit);
> +
> +MODULE_VERSION("0.0.0");
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("Hardware vhost accelerator abstraction");
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> index 5dc174ac8cac..0f7236a17a56 100644
> --- a/drivers/vhost/vhost.c
> +++ b/drivers/vhost/vhost.c
> @@ -426,8 +426,7 @@ bool vhost_exceeds_weight(struct vhost_virtqueue *vq,
> }
> EXPORT_SYMBOL_GPL(vhost_exceeds_weight);
>
> -static size_t vhost_get_avail_size(struct vhost_virtqueue *vq,
> - unsigned int num)
> +size_t vhost_get_avail_size(struct vhost_virtqueue *vq, unsigned int num)
> {
> size_t event __maybe_unused =
> vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
> @@ -435,9 +434,9 @@ static size_t vhost_get_avail_size(struct vhost_virtqueue *vq,
> return sizeof(*vq->avail) +
> sizeof(*vq->avail->ring) * num + event;
> }
> +EXPORT_SYMBOL_GPL(vhost_get_avail_size);
>
> -static size_t vhost_get_used_size(struct vhost_virtqueue *vq,
> - unsigned int num)
> +size_t vhost_get_used_size(struct vhost_virtqueue *vq, unsigned int num)
> {
> size_t event __maybe_unused =
> vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
> @@ -445,12 +444,13 @@ static size_t vhost_get_used_size(struct vhost_virtqueue *vq,
> return sizeof(*vq->used) +
> sizeof(*vq->used->ring) * num + event;
> }
> +EXPORT_SYMBOL_GPL(vhost_get_used_size);
>
> -static size_t vhost_get_desc_size(struct vhost_virtqueue *vq,
> - unsigned int num)
> +size_t vhost_get_desc_size(struct vhost_virtqueue *vq, unsigned int num)
> {
> return sizeof(*vq->desc) * num;
> }
> +EXPORT_SYMBOL_GPL(vhost_get_desc_size);
>
> void vhost_dev_init(struct vhost_dev *dev,
> struct vhost_virtqueue **vqs, int nvqs,
> @@ -2617,6 +2617,33 @@ struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev,
> }
> EXPORT_SYMBOL_GPL(vhost_dequeue_msg);
>
> +bool vhost_translate_ring_addr(struct vhost_virtqueue *vq, u64 ring_addr,
> + u64 len, u64 *addr)
> +{
> + struct vhost_umem *umem = vq->umem;
> + struct vhost_umem_node *u;
> +
> + if (vhost_overflow(ring_addr, len))
> + return false;
> +
> + if (vq->iotlb) {
> + /* Ring address is already IOVA */
> + *addr = ring_addr;
> + return true;
> + }
> +
> + /* Ring address is host virtual address. */
> + list_for_each_entry(u, &umem->umem_list, link) {
> + if (u->userspace_addr <= ring_addr &&
> + u->userspace_addr + u->size >= ring_addr + len) {
> + *addr = ring_addr - u->userspace_addr + u->start;
> + return true;
> + }
> + }
> +
> + return false;
> +}
> +EXPORT_SYMBOL_GPL(vhost_translate_ring_addr);


As we've discussed, this is necessary.


Thanks


>
> static int __init vhost_init(void)
> {
> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> index e9ed2722b633..294a6bcb6adf 100644
> --- a/drivers/vhost/vhost.h
> +++ b/drivers/vhost/vhost.h
> @@ -189,6 +189,12 @@ long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp);
> long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp);
> bool vhost_vq_access_ok(struct vhost_virtqueue *vq);
> bool vhost_log_access_ok(struct vhost_dev *);
> +bool vhost_translate_ring_addr(struct vhost_virtqueue *vq, u64 ring_addr,
> + u64 len, u64 *addr);
> +
> +size_t vhost_get_avail_size(struct vhost_virtqueue *vq, unsigned int num);
> +size_t vhost_get_used_size(struct vhost_virtqueue *vq, unsigned int num);
> +size_t vhost_get_desc_size(struct vhost_virtqueue *vq, unsigned int num);
>
> int vhost_get_vq_desc(struct vhost_virtqueue *,
> struct iovec iov[], unsigned int iov_count,
> diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
> index 40d028eed645..7213aedc8506 100644
> --- a/include/uapi/linux/vhost.h
> +++ b/include/uapi/linux/vhost.h
> @@ -116,4 +116,14 @@
> #define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64)
> #define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int)
>
> +/* VHOST_MDEV specific defines */
> +
> +#define VHOST_MDEV_SET_BACKEND _IOW(VHOST_VIRTIO, 0x70, \
> + struct vhost_mdev_backend)
> +#define VHOST_MDEV_SET_STATE _IOW(VHOST_VIRTIO, 0x71, __u64)
> +
> +#define VHOST_MDEV_S_STOPPED 0
> +#define VHOST_MDEV_S_RUNNING 1
> +#define VHOST_MDEV_S_MAX 2
> +
> #endif
> diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h
> index c907290ff065..f06f0dbb7e51 100644
> --- a/include/uapi/linux/vhost_types.h
> +++ b/include/uapi/linux/vhost_types.h
> @@ -119,6 +119,11 @@ struct vhost_scsi_target {
> unsigned short reserved;
> };
>
> +struct vhost_mdev_backend {
> + int group_fd;
> + int device_fd;
> +};
> +
> /* Feature bits */
> /* Log all write descriptors. Can be changed while device is active. */
> #define VHOST_F_LOG_ALL 26

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