[dpdk-dev] [RFC 3/3] net/virtio: add MAC device config getter and setter

[Adrian Moreno]

On 3/18/21 11:35 PM, Maxime Coquelin wrote:
> This patch uses the new device config ops to get and set
> the MAC address if supported.
> 
> If a valid MAC address is passed as devarg of the
> Virtio-user PMD, the driver will try to store it in the
> device config space. Otherwise the one provided in
> the device config space will be used, if available.
> 
> Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
> ---
>  .../net/virtio/virtio_user/virtio_user_dev.c  | 78 ++++++++++++++++---
>  .../net/virtio/virtio_user/virtio_user_dev.h  |  2 +
>  drivers/net/virtio/virtio_user_ethdev.c       |  7 +-
>  3 files changed, 74 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> index 8757a23f6e..61517692b3 100644
> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> @@ -259,20 +259,76 @@ int virtio_user_stop_device(struct virtio_user_dev *dev)
>  	return -1;
>  }
>  
> -static inline void
> -parse_mac(struct virtio_user_dev *dev, const char *mac)
> +int
> +virtio_user_dev_set_mac(struct virtio_user_dev *dev)
>  {
> -	struct rte_ether_addr tmp;
> +	int ret = 0;
>  
> -	if (!mac)
> -		return;
> +	if (!(dev->device_features & (1ULL << VIRTIO_NET_F_MAC)))
> +		return -ENOTSUP;
> +
> +	if (!dev->ops->set_config)
> +		return -ENOTSUP;
> +
> +	ret = dev->ops->set_config(dev, dev->mac_addr,
> +			offsetof(struct virtio_net_config, mac),
> +			RTE_ETHER_ADDR_LEN);
> +	if (ret)
> +		PMD_DRV_LOG(ERR, "(%s) Failed to set MAC address in device\n", dev->path);
> +
> +	return ret;
> +}
> +
> +int
> +virtio_user_dev_get_mac(struct virtio_user_dev *dev)
> +{
> +	int ret = 0;
> +
> +	if (!(dev->device_features & (1ULL << VIRTIO_NET_F_MAC)))
> +		return -ENOTSUP;
> +
> +	if (!dev->ops->get_config)
> +		return -ENOTSUP;
> +
> +	ret = dev->ops->get_config(dev, dev->mac_addr,
> +			offsetof(struct virtio_net_config, mac),
> +			RTE_ETHER_ADDR_LEN);
> +	if (ret)
> +		PMD_DRV_LOG(ERR, "(%s) Failed to get MAC address from device\n", dev->path);
>  
> -	if (rte_ether_unformat_addr(mac, &tmp) == 0) {
> -		memcpy(dev->mac_addr, &tmp, RTE_ETHER_ADDR_LEN);
> +	return ret;
> +}
> +
> +static void
> +virtio_user_dev_init_mac(struct virtio_user_dev *dev, const char *mac)
> +{
> +	struct rte_ether_addr cmdline_mac;
> +	int ret;
> +
> +	if (mac && rte_ether_unformat_addr(mac, &cmdline_mac) == 0) {
> +		/*
> +		 * MAC address was passed from command-line, try to store
> +		 * it in the device if it supports it. Otherwise try to use
> +		 * the device one.
> +		 */
> +		memcpy(dev->mac_addr, &cmdline_mac, RTE_ETHER_ADDR_LEN);
>  		dev->mac_specified = 1;
> +
> +		/* Setting MAC may fail, continue to get the device one in this case */
> +		virtio_user_dev_set_mac(dev);
> +		ret = virtio_user_dev_get_mac(dev);
> +		if (ret == -ENOTSUP)
> +			return;
> +
> +		if (memcmp(&cmdline_mac, dev->mac_addr, RTE_ETHER_ADDR_LEN))
> +			PMD_DRV_LOG(INFO, "(%s) Device MAC update failed\n", dev->path);

Maybe log the mac that we've read if it differs from the one we tried to write?

>  	} else {
> -		/* ignore the wrong mac, use random mac */
> -		PMD_DRV_LOG(ERR, "wrong format of mac: %s", mac);
> +		ret = virtio_user_dev_get_mac(dev);
> +		if (ret)
> +			PMD_DRV_LOG(ERR, "(%s) No valid MAC in devargs or device, use random\n",
> +					dev->path);
> +		else
> +			dev->mac_specified = 1;
>  	}
>  }
>  
> @@ -508,8 +564,6 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
>  	dev->unsupported_features = 0;
>  	dev->backend_type = backend_type;
>  
> -	parse_mac(dev, mac);
> -
>  	if (*ifname) {
>  		dev->ifname = *ifname;
>  		*ifname = NULL;
> @@ -537,6 +591,8 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
>  		return -1;
>  	}
>  
> +	virtio_user_dev_init_mac(dev, mac);
> +
>  	if (!mrg_rxbuf)
>  		dev->unsupported_features |= (1ull << VIRTIO_NET_F_MRG_RXBUF);
>  
> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.h b/drivers/net/virtio/virtio_user/virtio_user_dev.h
> index 8a62f7ea79..03bcf95970 100644
> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.h
> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.h
> @@ -78,6 +78,8 @@ uint8_t virtio_user_handle_mq(struct virtio_user_dev *dev, uint16_t q_pairs);
>  int virtio_user_dev_set_status(struct virtio_user_dev *dev, uint8_t status);
>  int virtio_user_dev_update_status(struct virtio_user_dev *dev);
>  int virtio_user_dev_update_link_state(struct virtio_user_dev *dev);
> +int virtio_user_dev_set_mac(struct virtio_user_dev *dev);
> +int virtio_user_dev_get_mac(struct virtio_user_dev *dev);
>  void virtio_user_dev_delayed_handler(void *param);
>  int virtio_user_dev_server_reconnect(struct virtio_user_dev *dev);
>  extern const char * const virtio_user_backend_strings[];
> diff --git a/drivers/net/virtio/virtio_user_ethdev.c b/drivers/net/virtio/virtio_user_ethdev.c
> index bb36316186..34c8e7a9b5 100644
> --- a/drivers/net/virtio/virtio_user_ethdev.c
> +++ b/drivers/net/virtio/virtio_user_ethdev.c
> @@ -60,12 +60,15 @@ virtio_user_write_dev_config(struct virtio_hw *hw, size_t offset,
>  	struct virtio_user_dev *dev = virtio_user_get_dev(hw);
>  
>  	if ((offset == offsetof(struct virtio_net_config, mac)) &&
> -	    (length == RTE_ETHER_ADDR_LEN))
> +	    (length == RTE_ETHER_ADDR_LEN)) {
>  		for (i = 0; i < RTE_ETHER_ADDR_LEN; ++i)
>  			dev->mac_addr[i] = ((const uint8_t *)src)[i];
> -	else
> +		virtio_user_dev_set_mac(dev);
> +		virtio_user_dev_get_mac(dev);
> +	} else {
>  		PMD_DRV_LOG(ERR, "not supported offset=%zu, len=%d",
>  			    offset, length);
> +	}
>  }
>  
>  static void
> 

-- 
Adrián Moreno