Re: [Qemu-devel] [PATCH] virtio-net: only output the vlan table when VIRTIO_NET_F_CTRL_VLAN is negotiated

[Vlad Yasevich <vyasevic@redhat.com>]

On 02/16/2014 09:27 PM, Amos Kong wrote:
> Stefan Fritsch just fixed a virtio-net driver bug [1], virtio-net won't
> filter out VLAN-tagged packets if VIRTIO_NET_F_CTRL_VLAN isn't negotiated.
> 
> We should also not send the vlan table to management, this patch makes
> the vlan-talbe optional.
      ^^^^^^^^^^
       table.

One question I have from the API perspective is can we suddenly change
something to be optional?  If there are any users of this ,
wouldn't they have to change now to check the existence of this
list?

Thanks
-vlad

> [1] http://lists.nongnu.org/archive/html/qemu-devel/2014-02/msg02604.html
> 
> Signed-off-by: Amos Kong <akong@redhat.com>
> ---
>  hw/net/virtio-net.c | 38 +++++++++++++++++++++++++-------------
>  qapi-schema.json    |  4 ++--
>  qmp-commands.hx     |  2 +-
>  3 files changed, 28 insertions(+), 16 deletions(-)
> 
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index 3626608..0b32e6a 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -222,13 +222,33 @@ static char *mac_strdup_printf(const uint8_t *mac)
>                              mac[1], mac[2], mac[3], mac[4], mac[5]);
>  }
>  
> +static intList *get_vlan_table(VirtIONet *n)
> +{
> +    intList *list, *entry;
> +    int i, j;
> +
> +    list = NULL;
> +    for (i = 0; i < MAX_VLAN >> 5; i++) {
> +        for (j = 0; n->vlans[i] && j < 0x1f; j++) {
> +            if (n->vlans[i] & (1U << j)) {
> +                entry = g_malloc0(sizeof(*entry));
> +                entry->value = (i << 5) + j;
> +                entry->next = list;
> +                list = entry;
> +            }
> +        }
> +    }
> +
> +    return list;
> +}
> +
>  static RxFilterInfo *virtio_net_query_rxfilter(NetClientState *nc)
>  {
>      VirtIONet *n = qemu_get_nic_opaque(nc);
> +    VirtIODevice *vdev = VIRTIO_DEVICE(n);
>      RxFilterInfo *info;
>      strList *str_list, *entry;
> -    intList *int_list, *int_entry;
> -    int i, j;
> +    int i;
>  
>      info = g_malloc0(sizeof(*info));
>      info->name = g_strdup(nc->name);
> @@ -274,18 +294,10 @@ static RxFilterInfo *virtio_net_query_rxfilter(NetClientState *nc)
>      }
>      info->multicast_table = str_list;
>  
> -    int_list = NULL;
> -    for (i = 0; i < MAX_VLAN >> 5; i++) {
> -        for (j = 0; n->vlans[i] && j < 0x1f; j++) {
> -            if (n->vlans[i] & (1U << j)) {
> -                int_entry = g_malloc0(sizeof(*int_entry));
> -                int_entry->value = (i << 5) + j;
> -                int_entry->next = int_list;
> -                int_list = int_entry;
> -            }
> -        }
> +    if ((1 << VIRTIO_NET_F_CTRL_VLAN) & vdev->guest_features) {
> +        info->has_vlan_table = true;
> +        info->vlan_table = get_vlan_table(n);
>      }
> -    info->vlan_table = int_list;

>  
>      /* enable event notification after query */
>      nc->rxfilter_notify_enabled = 1;
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 7cfb5e5..5d48fa9 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -4034,7 +4034,7 @@
>  #
>  # @main-mac: the main macaddr string
>  #
> -# @vlan-table: a list of active vlan id
> +# @vlan-table: #optional a list of active vlan id
>  #
>  # @unicast-table: a list of unicast macaddr string
>  #
> @@ -4053,7 +4053,7 @@
>      'multicast-overflow': 'bool',
>      'unicast-overflow':   'bool',
>      'main-mac':           'str',
> -    'vlan-table':         ['int'],
> +    '*vlan-table':         ['int'],
>      'unicast-table':      ['str'],
>      'multicast-table':    ['str'] }}
>  
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index cce6b81..a1c1dfa 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -3308,7 +3308,7 @@ Each array entry contains the following:
>  - "multicast-overflow": multicast table is overflowed (json-bool)
>  - "unicast-overflow": unicast table is overflowed (json-bool)
>  - "main-mac": main macaddr string (json-string)
> -- "vlan-table": a json-array of active vlan id
> +- "vlan-table": a json-array of active vlan id (optoinal)
>  - "unicast-table": a json-array of unicast macaddr string
>  - "multicast-table": a json-array of multicast macaddr string
>  
>