On 07/28/2015 05:25 PM, Fam Zheng wrote:
> Let net_rx_packet() (which checks the same conditions) drops the packet
> if the device is not ready. Drop net_xen_info.can_receive and update the
> return value for the buffer full case.
>
> We rely on the qemu_flush_queued_packets() in net_event() to wake up
> the peer when the buffer becomes available again.
>
> Signed-off-by: Fam Zheng <f...@redhat.com>
>
> ---
>
> v2:
> Fix return value of net_rx_packet to keep the semantics when ring
> buffer is full. [Stefan]
> Update commit message accordingly.
> ---
> hw/net/xen_nic.c | 24 +-----------------------
> 1 file changed, 1 insertion(+), 23 deletions(-)
>
> diff --git a/hw/net/xen_nic.c b/hw/net/xen_nic.c
> index 19ecfc4..acb7e2e 100644
> --- a/hw/net/xen_nic.c
> +++ b/hw/net/xen_nic.c
> @@ -234,27 +234,6 @@ static void net_rx_response(struct XenNetDev *netdev,
>
> #define NET_IP_ALIGN 2
>
> -static int net_rx_ok(NetClientState *nc)
> -{
> - struct XenNetDev *netdev = qemu_get_nic_opaque(nc);
> - RING_IDX rc, rp;
> -
> - if (netdev->xendev.be_state != XenbusStateConnected) {
> - return 0;
> - }
> -
> - rc = netdev->rx_ring.req_cons;
> - rp = netdev->rx_ring.sring->req_prod;
> - xen_rmb();
> -
> - if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) {
> - xen_be_printf(&netdev->xendev, 2, "%s: no rx buffers (%d/%d)\n",
> - __FUNCTION__, rc, rp);
> - return 0;
> - }
> - return 1;
> -}
> -
> static ssize_t net_rx_packet(NetClientState *nc, const uint8_t *buf, size_t
> size)
> {
> struct XenNetDev *netdev = qemu_get_nic_opaque(nc);
> @@ -272,7 +251,7 @@ static ssize_t net_rx_packet(NetClientState *nc, const
> uint8_t *buf, size_t size
>
> if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) {
> xen_be_printf(&netdev->xendev, 2, "no buffer, drop packet\n");
IIUC, 'return 0' means that the packet will be queued in the incoming queue. So
the log should
be changed too.
Thanks
Wen Congyang
> - return -1;
> + return 0;
> }
> if (size > XC_PAGE_SIZE - NET_IP_ALIGN) {
> xen_be_printf(&netdev->xendev, 0, "packet too big (%lu > %ld)",
> @@ -304,7 +283,6 @@ static ssize_t net_rx_packet(NetClientState *nc, const
> uint8_t *buf, size_t size
> static NetClientInfo net_xen_info = {
> .type = NET_CLIENT_OPTIONS_KIND_NIC,
> .size = sizeof(NICState),
> - .can_receive = net_rx_ok,
> .receive = net_rx_packet,
> };
>
>
