Hello,
On 9/1/24 11:27 PM, Jason Wang wrote:
> On Fri, Aug 30, 2024 at 9:15 PM Carlos Bilbao <cbilbao@xxxxxxxxxxxxxxxx> wrote:
>> Hello,
>>
>> On 8/29/24 9:31 PM, Jason Wang wrote:
>>> On Fri, Aug 30, 2024 at 5:08 AM Dragos Tatulea <dtatulea@xxxxxxxxxx> wrote:
>>>> (resending as I accidentally replied only to Carlos)
>>>>
>>>> On 29.08.24 18:16, Carlos Bilbao wrote:
>>>>> From: Carlos Bilbao <cbilbao@xxxxxxxxxxxxxxxx>
>>>>>
>>>>> Include support to update the vDPA configuration fields of speed and
>>>>> duplex (as needed by VHOST_VDPA_SET_CONFIG). This includes function
>>>>> mlx5_vdpa_set_config() as well as changes in vdpa.c to fill the initial
>>>>> values to UNKNOWN. Also add a warning message for when
>>>>> mlx5_vdpa_get_config() receives offset and length out of bounds.
>>>>>
>>>>> Signed-off-by: Carlos Bilbao <cbilbao@xxxxxxxxxxxxxxxx>
>>>>> ---
>>>>> drivers/vdpa/mlx5/net/mlx5_vnet.c | 34 ++++++++++++++++++++++++++++++-
>>>>> drivers/vdpa/vdpa.c | 27 ++++++++++++++++++++++++
>>>>> include/uapi/linux/vdpa.h | 2 ++
>>>>> 3 files changed, 62 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
>>>>> index c47009a8b472..a44bb2072eec 100644
>>>>> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
>>>>> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
>>>>> @@ -3221,12 +3221,44 @@ static void mlx5_vdpa_get_config(struct vdpa_device *vdev, unsigned int offset,
>>>>>
>>>>> if (offset + len <= sizeof(struct virtio_net_config))
>>>>> memcpy(buf, (u8 *)&ndev->config + offset, len);
>>>>> + else
>>>>> + mlx5_vdpa_warn(mvdev, "Offset and length out of bounds\n");
>>>>> }
>>>>>
>>>>> static void mlx5_vdpa_set_config(struct vdpa_device *vdev, unsigned int offset, const void *buf,
>>>>> unsigned int len)
>>>>> {
>>>>> - /* not supported */
>>>>> + struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
>>>>> + struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
>>>>> +
>>>>> + if (offset + len > sizeof(struct virtio_net_config)) {
>>>>> + mlx5_vdpa_warn(mvdev, "Offset and length out of bounds\n");
>>>>> + return;
>>>>> + }
>>>>> +
>>>>> + /*
>>>>> + * Note that this will update the speed/duplex configuration fields
>>>>> + * but the hardware support to actually perform this change does
>>>>> + * not exist yet.
>>>>> + */
>>>>> + switch (offset) {
>>>>> + case offsetof(struct virtio_net_config, speed):
>>>>> + if (len == sizeof(((struct virtio_net_config *) 0)->speed))
>>>>> + memcpy(&ndev->config.speed, buf, len);
>>>>> + else
>>>>> + mlx5_vdpa_warn(mvdev, "Invalid length for speed.\n");
>>>>> + break;
>>>>> +
>>>>> + case offsetof(struct virtio_net_config, duplex):
>>>>> + if (len == sizeof(((struct virtio_net_config *)0)->duplex))
>>>>> + memcpy(&ndev->config.duplex, buf, len);
>>>>> + else
>>>>> + mlx5_vdpa_warn(mvdev, "Invalid length for duplex.\n");
>>>>> + break;
>>>>> +
>>>>> + default:
>>>>> + mlx5_vdpa_warn(mvdev, "Configuration field not supported.\n");
>>>> This will trigger noise in dmesg because there is a MAC configuration here.
>>>>> + }
>>>> I would prefer that the .set_config remains a stub TBH. Setting the fields here is
>>>> misleading: the user might deduce that the configuration worked when they read the
>>>> values and see that they were updated.
>>> Yes, and actually, those fields are read-only according to the spec:
>>>
>>> """
>>> The network device has the following device configuration layout. All
>>> of the device configuration fields are read-only for the driver.
>>> """
>>>
>>> Thanks
>>
>> Should I go ahead and remove the ioctl then?
> If you meant mlx5_vdpa_set_config, I think yes.
Ack, I will send a new patch set in which the second commit gets rid of the
ioctl -- but not only for mlx5 but for all vDPA implementations.
>
> Thanks
>
Thanks, Carlos
