[dpdk-dev] [PATCH 2/3] vhost: Add callback and private data for vhost PMD

[Loftus, Ciara]

> 
> These variables are needed to be able to manage one of virtio devices
> using both vhost library APIs and vhost PMD.
> For example, if vhost PMD uses current callback handler and private data
> provided by vhost library, A DPDK application that links vhost library
> cannot use some of vhost library APIs. To avoid it, callback and private
> data for vhost PMD are needed.
> 
> Signed-off-by: Tetsuya Mukawa <mukawa at igel.co.jp>
> ---
>  lib/librte_vhost/rte_vhost_version.map        |  6 +++
>  lib/librte_vhost/rte_virtio_net.h             |  3 ++
>  lib/librte_vhost/vhost_user/virtio-net-user.c | 13 +++----
>  lib/librte_vhost/virtio-net.c                 | 56 +++++++++++++++++++++++++--
>  lib/librte_vhost/virtio-net.h                 |  4 +-
>  5 files changed, 70 insertions(+), 12 deletions(-)
> 
> diff --git a/lib/librte_vhost/rte_vhost_version.map
> b/lib/librte_vhost/rte_vhost_version.map
> index 3d8709e..00a9ce5 100644
> --- a/lib/librte_vhost/rte_vhost_version.map
> +++ b/lib/librte_vhost/rte_vhost_version.map
> @@ -20,3 +20,9 @@ DPDK_2.1 {
>  	rte_vhost_driver_unregister;
> 
>  } DPDK_2.0;
> +
> +DPDK_2.2 {
> +	global:
> +
> +	rte_vhost_driver_pmd_callback_register;
> +} DPDK_2.1;
> diff --git a/lib/librte_vhost/rte_virtio_net.h
> b/lib/librte_vhost/rte_virtio_net.h
> index 426a70d..08e77af 100644
> --- a/lib/librte_vhost/rte_virtio_net.h
> +++ b/lib/librte_vhost/rte_virtio_net.h
> @@ -106,6 +106,7 @@ struct virtio_net {
>  	char			ifname[IF_NAME_SZ];	/**< Name of the tap
> device or socket path. */
>  	uint32_t		virt_qp_nb;	/**< number of queue pair
> we have allocated */
>  	void			*priv;		/**< private context */
> +	void			*pmd_priv;	/**< private context for
> vhost PMD */
>  	struct vhost_virtqueue
> 	*virtqueue[VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX];	/**< Contains
> all virtqueue information. */
>  } __rte_cache_aligned;
> 
> @@ -202,6 +203,8 @@ int rte_vhost_driver_unregister(const char
> *dev_name);
> 
>  /* Register callbacks. */
>  int rte_vhost_driver_callback_register(struct virtio_net_device_ops const *
> const);
> +/* Register callbacks for vhost PMD (Only for internal). */
> +int rte_vhost_driver_pmd_callback_register(struct virtio_net_device_ops
> const * const);
>  /* Start vhost driver session blocking loop. */
>  int rte_vhost_driver_session_start(void);
> 
> diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.c
> b/lib/librte_vhost/vhost_user/virtio-net-user.c
> index 3e8dfea..dad083b 100644
> --- a/lib/librte_vhost/vhost_user/virtio-net-user.c
> +++ b/lib/librte_vhost/vhost_user/virtio-net-user.c
> @@ -111,7 +111,7 @@ user_set_mem_table(struct vhost_device_ctx ctx,
> struct VhostUserMsg *pmsg)
> 
>  	/* Remove from the data plane. */
>  	if (dev->flags & VIRTIO_DEV_RUNNING)
> -		notify_ops->destroy_device(dev);
> +		notify_destroy_device(dev);
> 
>  	if (dev->mem) {
>  		free_mem_region(dev);
> @@ -272,7 +272,7 @@ user_set_vring_kick(struct vhost_device_ctx ctx,
> struct VhostUserMsg *pmsg)
> 
>  	if (virtio_is_ready(dev) &&
>  		!(dev->flags & VIRTIO_DEV_RUNNING))
> -			notify_ops->new_device(dev);
> +			notify_new_device(dev);
>  }
> 
>  /*
> @@ -307,7 +307,7 @@ user_get_vring_base(struct vhost_device_ctx ctx,
>  	if ((dev->flags & VIRTIO_DEV_RUNNING) &&
>  			(dev->virtqueue[base_idx + VIRTIO_RXQ]->kickfd ==
> -1) &&
>  			(dev->virtqueue[base_idx + VIRTIO_TXQ]->kickfd ==
> -1))
> -		notify_ops->destroy_device(dev);
> +		notify_destroy_device(dev);
> 
>  	return 0;
>  }
> @@ -328,10 +328,7 @@ user_set_vring_enable(struct vhost_device_ctx ctx,
>  		"set queue enable: %d to qp idx: %d\n",
>  		enable, state->index);
> 
> -	if (notify_ops->vring_state_changed) {
> -		notify_ops->vring_state_changed(dev, base_idx /
> VIRTIO_QNUM,
> -						enable);
> -	}
> +	notify_vring_state_changed(dev, base_idx / VIRTIO_QNUM,
> enable);
> 
>  	dev->virtqueue[base_idx + VIRTIO_RXQ]->enabled = enable;
>  	dev->virtqueue[base_idx + VIRTIO_TXQ]->enabled = enable;
> @@ -345,7 +342,7 @@ user_destroy_device(struct vhost_device_ctx ctx)
>  	struct virtio_net *dev = get_device(ctx);
> 
>  	if (dev && (dev->flags & VIRTIO_DEV_RUNNING))
> -		notify_ops->destroy_device(dev);
> +		notify_destroy_device(dev);
> 
>  	if (dev && dev->mem) {
>  		free_mem_region(dev);
> diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
> index ee2e84d..de5d8ff 100644
> --- a/lib/librte_vhost/virtio-net.c
> +++ b/lib/librte_vhost/virtio-net.c
> @@ -65,6 +65,8 @@ struct virtio_net_config_ll {
> 
>  /* device ops to add/remove device to/from data core. */
>  struct virtio_net_device_ops const *notify_ops;
> +/* device ops for vhost PMD to add/remove device to/from data core. */
> +struct virtio_net_device_ops const *pmd_notify_ops;
>  /* root address of the linked list of managed virtio devices */
>  static struct virtio_net_config_ll *ll_root;
> 
> @@ -80,6 +82,43 @@ static struct virtio_net_config_ll *ll_root;
>  static uint64_t VHOST_FEATURES = VHOST_SUPPORTED_FEATURES;
> 
> 
> +int
> +notify_new_device(struct virtio_net *dev)
> +{
> +	if ((pmd_notify_ops != NULL) && (pmd_notify_ops->new_device !=
> NULL)) {
> +		int ret = pmd_notify_ops->new_device(dev);
> +		if (ret != 0)
> +			return ret;
> +	}
> +	if ((notify_ops != NULL) && (notify_ops->new_device != NULL))
> +		return notify_ops->new_device(dev);
> +
> +	return 0;
> +}
> +
> +void
> +notify_destroy_device(volatile struct virtio_net *dev)
> +{
> +	if ((pmd_notify_ops != NULL) && (pmd_notify_ops->destroy_device
> != NULL))
> +		pmd_notify_ops->destroy_device(dev);
> +	if ((notify_ops != NULL) && (notify_ops->destroy_device != NULL))
> +		notify_ops->destroy_device(dev);
> +}
> +
> +int
> +notify_vring_state_changed(struct virtio_net *dev, uint16_t queue_id, int
> enable)
> +{
> +	if ((pmd_notify_ops != NULL) && (pmd_notify_ops-
> >vring_state_changed != NULL)) {
> +		int ret = pmd_notify_ops->vring_state_changed(dev,
> queue_id, enable);
> +		if (ret != 0)
> +			return ret;
> +	}
> +	if ((notify_ops != NULL) && (notify_ops->vring_state_changed !=
> NULL))
> +		return notify_ops->vring_state_changed(dev, queue_id,
> enable);
> +
> +	return 0;
> +}
> +
>  /*
>   * Converts QEMU virtual address to Vhost virtual address. This function is
>   * used to convert the ring addresses to our address space.
> @@ -377,7 +416,7 @@ destroy_device(struct vhost_device_ctx ctx)
>  			 * 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));
> +				notify_destroy_device(&(ll_dev_cur->dev));
>  			ll_dev_cur = rm_config_ll_entry(ll_dev_cur,
>  					ll_dev_last);
>  		} else {
> @@ -794,12 +833,12 @@ set_backend(struct vhost_device_ctx ctx, struct
> vhost_vring_file *file)
>  	if (!(dev->flags & VIRTIO_DEV_RUNNING)) {
>  		if (((int)dev->virtqueue[base_idx + VIRTIO_RXQ]->backend
> != VIRTIO_DEV_STOPPED) &&
>  			((int)dev->virtqueue[base_idx + VIRTIO_TXQ]-
> >backend != VIRTIO_DEV_STOPPED)) {
> -			return notify_ops->new_device(dev);
> +			return notify_new_device(dev);
>  		}
>  	/* Otherwise we remove it. */
>  	} else
>  		if (file->fd == VIRTIO_DEV_STOPPED)
> -			notify_ops->destroy_device(dev);
> +			notify_destroy_device(dev);
>  	return 0;
>  }
> 
> @@ -883,3 +922,14 @@ rte_vhost_driver_callback_register(struct
> virtio_net_device_ops const * const op
> 
>  	return 0;
>  }
> +
> +/*
> + * Register ops so that we can add/remove device to data core.
> + */
> +int
> +rte_vhost_driver_pmd_callback_register(struct virtio_net_device_ops
> const * const ops)
> +{
> +	pmd_notify_ops = ops;
> +
> +	return 0;
> +}
> diff --git a/lib/librte_vhost/virtio-net.h b/lib/librte_vhost/virtio-net.h
> index 75fb57e..0816e71 100644
> --- a/lib/librte_vhost/virtio-net.h
> +++ b/lib/librte_vhost/virtio-net.h
> @@ -37,7 +37,9 @@
>  #include "vhost-net.h"
>  #include "rte_virtio_net.h"
> 
> -struct virtio_net_device_ops const *notify_ops;
>  struct virtio_net *get_device(struct vhost_device_ctx ctx);
> 
> +int notify_new_device(struct virtio_net *dev);
> +void notify_destroy_device(volatile struct virtio_net *dev);
> +int notify_vring_state_changed(struct virtio_net *dev, uint16_t queue_id,
> int enable);
>  #endif
> --
> 2.1.4

Hi Tetsuya,

Thanks for implementing this. I haven't had a chance to actually test it, but if these changes allow users of the PMD to implement their own new_ and destroy_ device functions etc, that's good news.

Thanks,
Ciara