[RFC,3/3] net/virtio: add MAC device config getter and setter

Message ID 20210318223526.168614-4-maxime.coquelin@redhat.com (mailing list archive)
State Superseded, archived
Delegated to: Maxime Coquelin
Headers
Series net/virtio: add vdpa device config support |

Checks

Context Check Description
ci/Intel-compilation success Compilation OK
ci/intel-Testing success Testing PASS

Commit Message

Maxime Coquelin March 18, 2021, 10:35 p.m. UTC
  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@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(-)
  

Comments

Adrian Moreno April 16, 2021, 9:27 a.m. UTC | #1
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@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
>
  
Chenbo Xia April 19, 2021, 6:24 a.m. UTC | #2
Hi Maxime,

> -----Original Message-----
> From: Maxime Coquelin <maxime.coquelin@redhat.com>
> Sent: Friday, March 19, 2021 6:35 AM
> To: dev@dpdk.org; Xia, Chenbo <chenbo.xia@intel.com>; amorenoz@redhat.com;
> david.marchand@redhat.com
> Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
> Subject: [RFC 3/3] net/virtio: add MAC device config getter and setter
> 
> 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.

I agree with the MAC selection strategy you proposed.

> 
> Signed-off-by: Maxime Coquelin <maxime.coquelin@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;

How do we define mac_specified? If I understand correctly, it means the mac
we see is from device (we set it or we just use device's). Then 'dev->mac_specified = 1'
should be after get_mac succeeds. Note that during virtio_user_dev_init, we also use
this val to set VIRTIO_NET_F_MAC. But here the val is set without making sure the
feature exists.

> +
> +		/* 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);

Besides Adrian's comments, if we decide to return no error on this, it may also
be good to add something like 'using random MAC' to tell users that the driver will
use random mac. Adding here or in the function that generates mac is both ok.

The patchset overall looks good to me. I'm looking forward to v1 😊

Thanks,
Chenbo

>  	} 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
> --
> 2.30.2
  
Maxime Coquelin June 3, 2021, 2:28 p.m. UTC | #3
Hi Chenbo,

On 4/19/21 8:24 AM, Xia, Chenbo wrote:
> Hi Maxime,
> 
>> -----Original Message-----
>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>> Sent: Friday, March 19, 2021 6:35 AM
>> To: dev@dpdk.org; Xia, Chenbo <chenbo.xia@intel.com>; amorenoz@redhat.com;
>> david.marchand@redhat.com
>> Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
>> Subject: [RFC 3/3] net/virtio: add MAC device config getter and setter
>>
>> 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.
> 
> I agree with the MAC selection strategy you proposed.
> 
>>
>> Signed-off-by: Maxime Coquelin <maxime.coquelin@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;
> 
> How do we define mac_specified? If I understand correctly, it means the mac
> we see is from device (we set it or we just use device's). Then 'dev->mac_specified = 1'
> should be after get_mac succeeds.

You are correct, mac_specified=1 means either user or device specified
MAC address. If get_mac fails below then we use the user specified MAC
address, so mac_specified = 1 is still valid in this case.

> Note that during virtio_user_dev_init, we also use
> this val to set VIRTIO_NET_F_MAC. But here the val is set without making sure the
> feature exists.

I am not sure to get youre point, but it sets VIRTIO_NET_F_MAC in the
frontend features there, that does not mean the feature is negotiated in
the end.

>> +
>> +		/* 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);
> 
> Besides Adrian's comments, if we decide to return no error on this, it may also
> be good to add something like 'using random MAC' to tell users that the driver will
> use random mac. Adding here or in the function that generates mac is both ok.

If it fails here, it won't be using a random MAC, but the MAC provided
by the user. The log could be improved with something like:
"Device MAC update failed, using MAC xx:xx:xx:xx:xx"

What do you think?

> The patchset overall looks good to me. I'm looking forward to v1 😊
> 
> Thanks,
> Chenbo

Thanks,
Maxime
  
Chenbo Xia June 8, 2021, 5:29 a.m. UTC | #4
Hi Maxime,

> -----Original Message-----
> From: Maxime Coquelin <mcoqueli@redhat.com>
> Sent: Thursday, June 3, 2021 10:29 PM
> To: Xia, Chenbo <chenbo.xia@intel.com>; Maxime Coquelin
> <maxime.coquelin@redhat.com>; dev@dpdk.org; amorenoz@redhat.com;
> david.marchand@redhat.com
> Subject: Re: [RFC 3/3] net/virtio: add MAC device config getter and setter
> 
> Hi Chenbo,
> 
> On 4/19/21 8:24 AM, Xia, Chenbo wrote:
> > Hi Maxime,
> >
> >> -----Original Message-----
> >> From: Maxime Coquelin <maxime.coquelin@redhat.com>
> >> Sent: Friday, March 19, 2021 6:35 AM
> >> To: dev@dpdk.org; Xia, Chenbo <chenbo.xia@intel.com>; amorenoz@redhat.com;
> >> david.marchand@redhat.com
> >> Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
> >> Subject: [RFC 3/3] net/virtio: add MAC device config getter and setter
> >>
> >> 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.
> >
> > I agree with the MAC selection strategy you proposed.
> >
> >>
> >> Signed-off-by: Maxime Coquelin <maxime.coquelin@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;
> >
> > How do we define mac_specified? If I understand correctly, it means the mac
> > we see is from device (we set it or we just use device's). Then 'dev-
> >mac_specified = 1'
> > should be after get_mac succeeds.
> 
> You are correct, mac_specified=1 means either user or device specified
> MAC address. If get_mac fails below then we use the user specified MAC
> address, so mac_specified = 1 is still valid in this case.
> 
> > Note that during virtio_user_dev_init, we also use
> > this val to set VIRTIO_NET_F_MAC. But here the val is set without making
> sure the
> > feature exists.
> 
> I am not sure to get youre point, but it sets VIRTIO_NET_F_MAC in the
> frontend features there, that does not mean the feature is negotiated in
> the end.

I think you are correct, I may misunderstood something when I review this first
time. And I want to make sure we are on the same page: since 'mac_specified=1'
will set VIRTIO_NET_F_MAC in frontend_features, so only when user don't set mac
and we don't get mac in device will lead to this feature unsupported, right?

> 
> >> +
> >> +		/* 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);
> >
> > Besides Adrian's comments, if we decide to return no error on this, it may
> also
> > be good to add something like 'using random MAC' to tell users that the
> driver will
> > use random mac. Adding here or in the function that generates mac is both ok.
> 
> If it fails here, it won't be using a random MAC, but the MAC provided
> by the user. The log could be improved with something like:
> "Device MAC update failed, using MAC xx:xx:xx:xx:xx"

Yeah! That's good.

Thanks,
Chenbo

> 
> What do you think?
> 
> > The patchset overall looks good to me. I'm looking forward to v1 😊
> >
> > Thanks,
> > Chenbo
> 
> Thanks,
> Maxime
  
Maxime Coquelin June 8, 2021, 6:22 a.m. UTC | #5
On 6/8/21 7:29 AM, Xia, Chenbo wrote:
> Hi Maxime,
> 
>> -----Original Message-----
>> From: Maxime Coquelin <mcoqueli@redhat.com>
>> Sent: Thursday, June 3, 2021 10:29 PM
>> To: Xia, Chenbo <chenbo.xia@intel.com>; Maxime Coquelin
>> <maxime.coquelin@redhat.com>; dev@dpdk.org; amorenoz@redhat.com;
>> david.marchand@redhat.com
>> Subject: Re: [RFC 3/3] net/virtio: add MAC device config getter and setter
>>
>> Hi Chenbo,
>>
>> On 4/19/21 8:24 AM, Xia, Chenbo wrote:
>>> Hi Maxime,
>>>
>>>> -----Original Message-----
>>>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>>>> Sent: Friday, March 19, 2021 6:35 AM
>>>> To: dev@dpdk.org; Xia, Chenbo <chenbo.xia@intel.com>; amorenoz@redhat.com;
>>>> david.marchand@redhat.com
>>>> Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
>>>> Subject: [RFC 3/3] net/virtio: add MAC device config getter and setter
>>>>
>>>> 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.
>>>
>>> I agree with the MAC selection strategy you proposed.
>>>
>>>>
>>>> Signed-off-by: Maxime Coquelin <maxime.coquelin@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;
>>>
>>> How do we define mac_specified? If I understand correctly, it means the mac
>>> we see is from device (we set it or we just use device's). Then 'dev-
>>> mac_specified = 1'
>>> should be after get_mac succeeds.
>>
>> You are correct, mac_specified=1 means either user or device specified
>> MAC address. If get_mac fails below then we use the user specified MAC
>> address, so mac_specified = 1 is still valid in this case.
>>
>>> Note that during virtio_user_dev_init, we also use
>>> this val to set VIRTIO_NET_F_MAC. But here the val is set without making
>> sure the
>>> feature exists.
>>
>> I am not sure to get youre point, but it sets VIRTIO_NET_F_MAC in the
>> frontend features there, that does not mean the feature is negotiated in
>> the end.
> 
> I think you are correct, I may misunderstood something when I review this first
> time. And I want to make sure we are on the same page: since 'mac_specified=1'
> will set VIRTIO_NET_F_MAC in frontend_features, so only when user don't set mac
> and we don't get mac in device will lead to this feature unsupported, right?

Yes, correct. The idea was to keep the old behaviour, i.e. support it
when user specifies the MAC in the devargs, and extend it to support the
feature when the device can provide the MAC address.

Regards,
Maxime

>>
>>>> +
>>>> +		/* 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);
>>>
>>> Besides Adrian's comments, if we decide to return no error on this, it may
>> also
>>> be good to add something like 'using random MAC' to tell users that the
>> driver will
>>> use random mac. Adding here or in the function that generates mac is both ok.
>>
>> If it fails here, it won't be using a random MAC, but the MAC provided
>> by the user. The log could be improved with something like:
>> "Device MAC update failed, using MAC xx:xx:xx:xx:xx"
> 
> Yeah! That's good.
> 
> Thanks,
> Chenbo
> 
>>
>> What do you think?
>>
>>> The patchset overall looks good to me. I'm looking forward to v1 😊
>>>
>>> Thanks,
>>> Chenbo
>>
>> Thanks,
>> Maxime
>
  

Patch

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);
 	} 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