[dpdk-dev] [PATCH 37/40] net/virtio: introduce backend data

[Adrian Moreno]

On 12/20/20 10:14 PM, Maxime Coquelin wrote:
> The goal of this patch is to introduce backend-specific
> data in order to better isolate what is backend-specific
> from what is generic to Virtio-user.
> 
> For now, only Vhost-user protocol features are moved to
> Vhost-user backend data.
> 
> Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
> ---
>  drivers/net/virtio/virtio_user/vhost.h        |  1 +
>  drivers/net/virtio/virtio_user/vhost_kernel.c |  7 +++
>  drivers/net/virtio/virtio_user/vhost_user.c   | 46 +++++++++++++++----
>  drivers/net/virtio/virtio_user/vhost_vdpa.c   |  8 ++++
>  .../net/virtio/virtio_user/virtio_user_dev.c  |  2 +
>  .../net/virtio/virtio_user/virtio_user_dev.h  |  3 +-
>  6 files changed, 58 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio_user/vhost.h b/drivers/net/virtio/virtio_user/vhost.h
> index b488ac78a1..ee5598226d 100644
> --- a/drivers/net/virtio/virtio_user/vhost.h
> +++ b/drivers/net/virtio/virtio_user/vhost.h
> @@ -57,6 +57,7 @@ struct virtio_user_dev;
>  
>  struct virtio_user_backend_ops {
>  	int (*setup)(struct virtio_user_dev *dev);
> +	int (*destroy)(struct virtio_user_dev *dev);
>  	int (*get_backend_features)(uint64_t *features);
>  	int (*set_owner)(struct virtio_user_dev *dev);
>  	int (*get_features)(struct virtio_user_dev *dev, uint64_t *features);
> diff --git a/drivers/net/virtio/virtio_user/vhost_kernel.c b/drivers/net/virtio/virtio_user/vhost_kernel.c
> index 2fd00afa84..023fddcd69 100644
> --- a/drivers/net/virtio/virtio_user/vhost_kernel.c
> +++ b/drivers/net/virtio/virtio_user/vhost_kernel.c
> @@ -357,6 +357,12 @@ vhost_kernel_setup(struct virtio_user_dev *dev)
>  	return 0;
>  }
>  
> +static int
> +vhost_kernel_destroy(struct virtio_user_dev *dev)
> +{
> +	return 0;
> +}
> +
>  static int
>  vhost_kernel_set_backend(int vhostfd, int tapfd)
>  {
> @@ -455,6 +461,7 @@ vhost_kernel_get_backend_features(uint64_t *features)
>  
>  struct virtio_user_backend_ops virtio_ops_kernel = {
>  	.setup = vhost_kernel_setup,
> +	.destroy = vhost_kernel_destroy,
>  	.get_backend_features = vhost_kernel_get_backend_features,
>  	.set_owner = vhost_kernel_set_owner,
>  	.get_features = vhost_kernel_get_features,
> diff --git a/drivers/net/virtio/virtio_user/vhost_user.c b/drivers/net/virtio/virtio_user/vhost_user.c
> index f67c40e047..e96b1d8b9c 100644
> --- a/drivers/net/virtio/virtio_user/vhost_user.c
> +++ b/drivers/net/virtio/virtio_user/vhost_user.c
> @@ -17,6 +17,9 @@
>  #include "vhost.h"
>  #include "virtio_user_dev.h"
>  
> +struct vhost_user_data {
> +	uint64_t protocol_features;
> +};
>  
>  #ifndef VHOST_USER_F_PROTOCOL_FEATURES
>  #define VHOST_USER_F_PROTOCOL_FEATURES 30
> @@ -274,6 +277,7 @@ static int
>  vhost_user_get_features(struct virtio_user_dev *dev, uint64_t *features)
>  {
>  	int ret;
> +	struct vhost_user_data *data = dev->backend_data;
>  	struct vhost_user_msg msg = {
>  		.request = VHOST_USER_GET_FEATURES,
>  		.flags = VHOST_USER_VERSION,
> @@ -303,17 +307,17 @@ vhost_user_get_features(struct virtio_user_dev *dev, uint64_t *features)
>  		return 0;
>  
>  	/* Negotiate protocol features */
> -	ret = vhost_user_get_protocol_features(dev, &dev->protocol_features);
> +	ret = vhost_user_get_protocol_features(dev, &data->protocol_features);
>  	if (ret < 0)
>  		goto err;
>  
> -	dev->protocol_features &= VHOST_USER_SUPPORTED_PROTOCOL_FEATURES;
> +	data->protocol_features &= VHOST_USER_SUPPORTED_PROTOCOL_FEATURES;
>  
> -	ret = vhost_user_set_protocol_features(dev, dev->protocol_features);
> +	ret = vhost_user_set_protocol_features(dev, data->protocol_features);
>  	if (ret < 0)
>  		goto err;
>  
> -	if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_MQ)))
> +	if (!(data->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_MQ)))
>  		dev->unsupported_features |= (1ull << VIRTIO_NET_F_MQ);
>  
>  	return 0;
> @@ -429,12 +433,13 @@ vhost_user_set_memory_table(struct virtio_user_dev *dev)
>  	struct walk_arg wa;
>  	int fds[VHOST_MEMORY_MAX_NREGIONS];
>  	int ret, fd_num;
> +	struct vhost_user_data *data = dev->backend_data;
>  	struct vhost_user_msg msg = {
>  		.request = VHOST_USER_SET_MEM_TABLE,
>  		.flags = VHOST_USER_VERSION,
>  	};
>  
> -	if (dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK))
> +	if (data->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK))
>  		msg.flags |= VHOST_USER_NEED_REPLY_MASK;
>  
>  	wa.region_nr = 0;
> @@ -613,6 +618,7 @@ static int
>  vhost_user_get_status(struct virtio_user_dev *dev, uint8_t *status)
>  {
>  	int ret;
> +	struct vhost_user_data *data = dev->backend_data;
>  	struct vhost_user_msg msg = {
>  		.request = VHOST_USER_GET_STATUS,
>  		.flags = VHOST_USER_VERSION,
> @@ -629,7 +635,7 @@ vhost_user_get_status(struct virtio_user_dev *dev, uint8_t *status)
>  	if (!(dev->device_features & (1ULL << VHOST_USER_F_PROTOCOL_FEATURES)))
>  		return -ENOTSUP;
>  
> -	if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_STATUS)))
> +	if (!(data->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_STATUS)))
>  		return -ENOTSUP;
>  
>  	ret = vhost_user_write(dev->vhostfd, &msg, NULL, 0);
> @@ -666,6 +672,7 @@ static int
>  vhost_user_set_status(struct virtio_user_dev *dev, uint8_t status)
>  {
>  	int ret;
> +	struct vhost_user_data *data = dev->backend_data;
>  	struct vhost_user_msg msg = {
>  		.request = VHOST_USER_SET_STATUS,
>  		.flags = VHOST_USER_VERSION,
> @@ -673,7 +680,7 @@ vhost_user_set_status(struct virtio_user_dev *dev, uint8_t status)
>  		.payload.u64 = status,
>  	};
>  
> -	if (dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK))
> +	if (data->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK))
>  		msg.flags |= VHOST_USER_NEED_REPLY_MASK;
>  
>  	/*
> @@ -687,7 +694,7 @@ vhost_user_set_status(struct virtio_user_dev *dev, uint8_t status)
>  	if (!(dev->device_features & (1ULL << VHOST_USER_F_PROTOCOL_FEATURES)))
>  		return -ENOTSUP;
>  
> -	if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_STATUS)))
> +	if (!(data->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_STATUS)))
>  		return -ENOTSUP;
>  
>  	ret = vhost_user_write(dev->vhostfd, &msg, NULL, 0);
> @@ -747,6 +754,17 @@ vhost_user_setup(struct virtio_user_dev *dev)
>  	int fd;
>  	int flag;
>  	struct sockaddr_un un;
> +	struct vhost_user_data *data;
> +
> +	data = malloc(sizeof(*data));
> +	if (!data) {
> +		PMD_DRV_LOG(ERR, "(%s) Failed to allocate Vhost-user data\n", dev->path);
> +		return -1;
> +	}
> +
> +	memset(data, 0, sizeof(*data));
> +
> +	dev->backend_data = data;
>  
>  	fd = socket(AF_UNIX, SOCK_STREAM, 0);
>  	if (fd < 0) {

There are a number of "return -1;" statements below which, if executed, would
now leak.
Also, there are two in virtio_user_dev.c:virtio_user_dev_setup()

> @@ -781,6 +799,17 @@ vhost_user_setup(struct virtio_user_dev *dev)
>  	return 0;
>  }
>  
> +static int
> +vhost_user_destroy(struct virtio_user_dev *dev)
> +{
> +	if (dev->backend_data) {
> +		free(dev->backend_data);
> +		dev->backend_data = NULL;
> +	}
> +
> +	return 0;
> +}
> +
>  static int
>  vhost_user_enable_queue_pair(struct virtio_user_dev *dev,
>  			     uint16_t pair_idx,
> @@ -815,6 +844,7 @@ vhost_user_get_backend_features(uint64_t *features)
>  
>  struct virtio_user_backend_ops virtio_ops_user = {
>  	.setup = vhost_user_setup,
> +	.destroy = vhost_user_destroy,
>  	.get_backend_features = vhost_user_get_backend_features,
>  	.set_owner = vhost_user_set_owner,
>  	.get_features = vhost_user_get_features,
> diff --git a/drivers/net/virtio/virtio_user/vhost_vdpa.c b/drivers/net/virtio/virtio_user/vhost_vdpa.c
> index c826f333e0..b29426d767 100644
> --- a/drivers/net/virtio/virtio_user/vhost_vdpa.c
> +++ b/drivers/net/virtio/virtio_user/vhost_vdpa.c
> @@ -287,6 +287,13 @@ vhost_vdpa_setup(struct virtio_user_dev *dev)
>  	return 0;
>  }
>  
> +static int
> +vhost_vdpa_destroy(struct virtio_user_dev *dev __rte_unused)
> +{
> +	return;
> +	return 0;
> +}
> +
>  static int
>  vhost_vdpa_enable_queue_pair(struct virtio_user_dev *dev,
>  			       uint16_t pair_idx,
> @@ -322,6 +329,7 @@ vhost_vdpa_get_backend_features(uint64_t *features)
>  
>  struct virtio_user_backend_ops virtio_ops_vdpa = {
>  	.setup = vhost_vdpa_setup,
> +	.destroy = vhost_vdpa_destroy,
>  	.get_backend_features = vhost_vdpa_get_backend_features,
>  	.set_owner = vhost_vdpa_set_owner,
>  	.get_features = vhost_vdpa_get_features,
> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> index 974de133bc..8d19a0addd 100644
> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> @@ -620,6 +620,8 @@ virtio_user_dev_uninit(struct virtio_user_dev *dev)
>  
>  	if (dev->is_server)
>  		unlink(dev->path);
> +
> +	dev->ops->destroy(dev);
>  }
>  
>  uint8_t
> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.h b/drivers/net/virtio/virtio_user/virtio_user_dev.h
> index b2da2944e9..ec73d5de11 100644
> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.h
> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.h
> @@ -30,7 +30,6 @@ struct virtio_user_dev {
>  	int		vhostfd;
>  	int		listenfd;   /* listening fd */
>  	bool		is_server;  /* server or client mode */
> -	uint64_t	protocol_features; /* negotiated protocol features*/
>  
>  	/* for vhost_kernel backend */
>  	char		*ifname;
> @@ -66,6 +65,8 @@ struct virtio_user_dev {
>  	struct virtio_user_backend_ops *ops;
>  	pthread_mutex_t	mutex;
>  	bool		started;
> +
> +	void *backend_data;
>  };
>  
>  int virtio_user_dev_set_features(struct virtio_user_dev *dev);
> 




-- 
Adrián Moreno