Re: [Qemu-devel] [V4 PATCH 3/5] net: model specific announcing support

[Michael S. Tsirkin]

On Tue, Mar 13, 2012 at 04:56:31PM +0800, Jason Wang wrote:
> This patch introduces a function pointer in NetClientInfo which is
> called during self announcement. With this, each kind of card can announce the
> link with a specific way. The old method is still kept for cards that have not
> implemented this or old guest. The first user would be virtio-net.
> 
> Signed-off-by: Jason Wang <address@hidden>
> ---
>  net.h    |    2 ++
>  savevm.c |    8 +++++---
>  2 files changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/net.h b/net.h
> index 75a8c15..7195bfc 100644
> --- a/net.h
> +++ b/net.h
> @@ -48,6 +48,7 @@ typedef ssize_t (NetReceive)(VLANClientState *, const 
> uint8_t *, size_t);
>  typedef ssize_t (NetReceiveIOV)(VLANClientState *, const struct iovec *, 
> int);
>  typedef void (NetCleanup) (VLANClientState *);
>  typedef void (LinkStatusChanged)(VLANClientState *);
> +typedef int (NetAnnounce)(VLANClientState *);
>  
>  typedef struct NetClientInfo {
>      net_client_type type;
> @@ -59,6 +60,7 @@ typedef struct NetClientInfo {
>      NetCleanup *cleanup;
>      LinkStatusChanged *link_status_changed;
>      NetPoll *poll;
> +    NetAnnounce *announce;
>  } NetClientInfo;
>  
>  struct VLANClientState {
> diff --git a/savevm.c b/savevm.c
> index 82b9d3a..0a901dc 100644
> --- a/savevm.c
> +++ b/savevm.c
> @@ -123,10 +123,12 @@ static void qemu_announce_self_iter(NICState *nic, void 
> *opaque)
>  {
>      uint8_t buf[60];
>      int len;
> +    NetAnnounce *func = nic->nc.info->announce;
>  
> -    len = announce_self_create(buf, nic->conf->macaddr.a);
> -
> -    qemu_send_packet_raw(&nic->nc, buf, len);
> +    if (func == NULL || func(&nic->nc) != 0) {

Shorter as !func || func(&nic->nc)

> +        len = announce_self_create(buf, nic->conf->macaddr.a);
> +        qemu_send_packet_raw(&nic->nc, buf, len);
> +    }
>  }
>  
>