Re: [Qemu-devel] [PATCH v4 for 2.0] virtio-net: add vlan receive state to RxFilterInfo

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Mar 26, 2014 at 08:19:43AM +0800, 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.

Yes but that fix is unfortunately wrong as it tests guest_features
on reset.
How about preparing a correct one?


> This patch added a new field to @RxFilterInfo to indicate vlan receive
> state ('normal', 'none', 'all'). If VIRTIO_NET_F_CTRL_VLAN isn't
> negotiated, vlan receive state will be 'all', then all VLAN-tagged packets
> will be received by guest.
> 
> This patch also fixed a boundary issue in visiting vlan table.
> 
> [1] http://lists.nongnu.org/archive/html/qemu-devel/2014-02/msg02604.html
> 
> Signed-off-by: Amos Kong <akong@redhat.com>
> ---
> V2: don't make vlan-table optional, add a flag to indicate
>     if vlan table is used by management
> V3: change the new filed to RxState (mst)
> V4: fix boundary of vlan mapping (eric)
> ---
>  hw/net/virtio-net.c | 42 +++++++++++++++++++++++++++++-------------
>  qapi-schema.json    |  3 +++
>  qmp-commands.hx     |  2 ++
>  3 files changed, 34 insertions(+), 13 deletions(-)
> 
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index fd23c46..43b4eda 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);
> @@ -273,19 +293,15 @@ static RxFilterInfo *virtio_net_query_rxfilter(NetClientState *nc)
>          str_list = entry;
>      }
>      info->multicast_table = str_list;
> +    info->vlan_table = get_vlan_table(n);
>  
> -    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->vlan = RX_STATE_ALL;
> +    } else if (!info->vlan_table) {
> +        info->vlan = RX_STATE_NONE;
> +    } else {
> +        info->vlan = RX_STATE_NORMAL;
>      }

Generally I'm not sure why do we have NONE - for mac
and unicast too - we could send an empty list instead.

I'm fine with keeping it as is for now though.

> -    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 b68cd44..391356f 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -4184,6 +4184,8 @@
>  #
>  # @unicast: unicast receive state
>  #
> +# @vlan: vlan receive state (Since 2.0)
> +#
>  # @broadcast-allowed: whether to receive broadcast
>  #
>  # @multicast-overflow: multicast table is overflowed or not
> @@ -4207,6 +4209,7 @@
>      'promiscuous':        'bool',
>      'multicast':          'RxState',
>      'unicast':            'RxState',
> +    'vlan':               'RxState',
>      'broadcast-allowed':  'bool',
>      'multicast-overflow': 'bool',
>      'unicast-overflow':   'bool',
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index a22621f..ed3ab92 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -3407,6 +3407,7 @@ Each array entry contains the following:
>  - "promiscuous": promiscuous mode is enabled (json-bool)
>  - "multicast": multicast receive state (one of 'normal', 'none', 'all')
>  - "unicast": unicast receive state  (one of 'normal', 'none', 'all')
> +- "vlan": vlan receive state (one of 'normal', 'none', 'all') (Since 2.0)
>  - "broadcast-allowed": allow to receive broadcast (json-bool)
>  - "multicast-overflow": multicast table is overflowed (json-bool)
>  - "unicast-overflow": unicast table is overflowed (json-bool)
> @@ -3424,6 +3425,7 @@ Example:
>              "name": "vnet0",
>              "main-mac": "52:54:00:12:34:56",
>              "unicast": "normal",
> +            "vlan": "normal",
>              "vlan-table": [
>                  4,
>                  0
> -- 
> 1.8.5.3