On 07.11.24 22:50, Michael S. Tsirkin wrote:
> On Wed, Sep 04, 2024 at 10:11:14AM -0500, Carlos Bilbao wrote:
>> From: Carlos Bilbao <[email protected]>
>>
>> Initialize the speed and duplex fields in virtio_net_config to UNKNOWN.
>> This is needed because mlx5_vdpa vDPA devices currently do not support the
>> VIRTIO_NET_F_SPEED_DUPLEX feature which reports speed and duplex.
>
> I see no logic here. Without this feature bit, guests will not read
> this field, why do we suddenly need to initialize it?
>
IIRC, Carlos was reading data via ioctl VHOST_VDPA_GET_CONFIG which calls
.get_config() directly, always exposing the speed and duplex config fields [0].
Carlos, was this the case?
[0]
https://lore.kernel.org/lkml/[email protected]/T/
Thanks,
Dragos
>> Add
>> needed helper cpu_to_mlx5vdpa32() to convert endianness of speed.
>>
>> Signed-off-by: Carlos Bilbao <[email protected]>
>> Reviewed-by: Dragos Tatulea <[email protected]>
>> ---
>> drivers/vdpa/mlx5/net/mlx5_vnet.c | 12 ++++++++++++
>> 1 file changed, 12 insertions(+)
>>
>> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c
>> b/drivers/vdpa/mlx5/net/mlx5_vnet.c
>> index b56aae3f7be3..41ca268d43ff 100644
>> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
>> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
>> @@ -173,6 +173,11 @@ static __virtio16 cpu_to_mlx5vdpa16(struct
>> mlx5_vdpa_dev *mvdev, u16 val)
>> return __cpu_to_virtio16(mlx5_vdpa_is_little_endian(mvdev), val);
>> }
>>
>> +static __virtio32 cpu_to_mlx5vdpa32(struct mlx5_vdpa_dev *mvdev, u32 val)
>> +{
>> + return __cpu_to_virtio32(mlx5_vdpa_is_little_endian(mvdev), val);
>> +}
>> +
>> static u16 ctrl_vq_idx(struct mlx5_vdpa_dev *mvdev)
>> {
>> if (!(mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_MQ)))
>> @@ -3433,6 +3438,13 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev
>> *v_mdev, const char *name,
>> init_rwsem(&ndev->reslock);
>> config = &ndev->config;
>>
>> + /*
>> + * mlx5_vdpa vDPA devices currently don't support reporting or
>> + * setting the speed or duplex.
>> + */
>> + config->speed = cpu_to_mlx5vdpa32(mvdev, SPEED_UNKNOWN);
>> + config->duplex = DUPLEX_UNKNOWN;
>> +
>> if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU)) {
>> err = config_func_mtu(mdev, add_config->net.mtu);
>> if (err)
>> --
>> 2.34.1
>
