Re: [PATCH RFC 2/3] vdpa: Restore packet receive filtering state relative with _F_CTRL_RX feature

[Hawkins Jiawei]

On 2023/6/25 18:56, Eugenio Perez Martin wrote:
> On Thu, Jun 22, 2023 at 5:02 AM Hawkins Jiawei <yin31149@gmail.com> wrote:
>>
>> This patch introduces vhost_vdpa_net_load_rx_mode()
>> and vhost_vdpa_net_load_rx() to restore the packet
>> receive filtering state in relation to
>> VIRTIO_NET_F_CTRL_RX feature at device's startup.
>>
>> Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
>> ---
>>   net/vhost-vdpa.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 74 insertions(+)
>>
>> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
>> index 10264d3e96..355a6aef15 100644
>> --- a/net/vhost-vdpa.c
>> +++ b/net/vhost-vdpa.c
>> @@ -754,6 +754,76 @@ static int vhost_vdpa_net_load_offloads(VhostVDPAState 
>> *s,
>>       return *s->status != VIRTIO_NET_OK;
>>   }
>>
>> +static int vhost_vdpa_net_load_rx_mode(VhostVDPAState *s,
>> +                                       uint8_t cmd,
>> +                                       uint8_t on)
>> +{
>> +    ssize_t dev_written;
>> +    dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_RX,
>> +                                          cmd, &on, sizeof(on));
>> +    if (unlikely(dev_written < 0)) {
>> +        return dev_written;
>> +    }
>> +    if (*s->status != VIRTIO_NET_OK) {
>> +        return -EINVAL;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static int vhost_vdpa_net_load_rx(VhostVDPAState *s,
>> +                                  const VirtIONet *n)
>> +{
>> +    uint8_t on;
>> +    int r;
>> +
>> +    if (virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_RX)) {
>> +        /* Load the promiscous mode */
>> +        if (n->mac_table.uni_overflow) {
>> +            /*
>> +             * According to VirtIO standard, "Since there are no guarantees,
>> +             * it can use a hash filter or silently switch to
>> +             * allmulti or promiscuous mode if it is given too many 
>> addresses."
>> +             *
>> +             * QEMU ignores non-multicast(unicast) MAC addresses and
>> +             * marks `uni_overflow` for the device internal state
>> +             * if guest sets too many non-multicast(unicast) MAC addresses.
>> +             * Therefore, we should turn promiscous mode on in this case.
>> +             */
>> +            on = 1;
>> +        } else {
>> +            on = n->promisc;
>> +        }
>> +        r = vhost_vdpa_net_load_rx_mode(s, VIRTIO_NET_CTRL_RX_PROMISC, on);
>> +        if (r < 0) {
>> +            return r;
>> +        }
>> +
>> +        /* Load the all-multicast mode */
>> +        if (n->mac_table.multi_overflow) {
>> +            /*
>> +             * According to VirtIO standard, "Since there are no guarantees,
>> +             * it can use a hash filter or silently switch to
>> +             * allmulti or promiscuous mode if it is given too many 
>> addresses."
>> +             *
>> +             * QEMU ignores multicast MAC addresses and
>> +             * marks `multi_overflow` for the device internal state
>> +             * if guest sets too many multicast MAC addresses.
>> +             * Therefore, we should turn all-multicast mode on in this case.
>> +             */
>> +            on = 1;
>> +        } else {
>> +            on = n->allmulti;
>> +        }
>> +        r = vhost_vdpa_net_load_rx_mode(s, VIRTIO_NET_CTRL_RX_ALLMULTI, on);
>> +        if (r < 0) {
>> +            return r;
>> +        }
>
> Can we skip the sending of the CVQ commands if the state matches the
> default state?

Thanks for your reminder, I forgot this part when coding. I will
refactor the patch according to your suggestion and take care of it in
the following patches for this part.

Thanks!


>
> Thanks!
>
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>>   static int vhost_vdpa_net_load(NetClientState *nc)
>>   {
>>       VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
>> @@ -780,6 +850,10 @@ static int vhost_vdpa_net_load(NetClientState *nc)
>>       if (unlikely(r)) {
>>           return r;
>>       }
>> +    r = vhost_vdpa_net_load_rx(s, n);
>> +    if (unlikely(r)) {
>> +        return r;
>> +    }
>>
>>       return 0;
>>   }
>> --
>> 2.25.1
>>
>