From 57b229063ae6dc65036209018dc7f4290cc026bb Mon Sep 17 00:00:00 2001 From: Ross Lagerwall Date: Tue, 4 Aug 2015 15:40:59 +0100 Subject: xen/netback: Wake dealloc thread after completing zerocopy work Waking the dealloc thread before decrementing inflight_packets is racy because it means the thread may go to sleep before inflight_packets is decremented. If kthread_stop() has already been called, the dealloc thread may wait forever with nothing to wake it. Instead, wake the thread only after decrementing inflight_packets. Signed-off-by: Ross Lagerwall Signed-off-by: David S. Miller --- drivers/net/xen-netback/interface.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/net/xen-netback/interface.c') diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 1a83e190fc15..28577a31549d 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -61,6 +61,12 @@ void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue, void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue) { atomic_dec(&queue->inflight_packets); + + /* Wake the dealloc thread _after_ decrementing inflight_packets so + * that if kthread_stop() has already been called, the dealloc thread + * does not wait forever with nothing to wake it. + */ + wake_up(&queue->dealloc_wq); } int xenvif_schedulable(struct xenvif *vif) -- cgit v1.2.3 From 210c34dcd8d912dcc740f1f17625a7293af5cb56 Mon Sep 17 00:00:00 2001 From: Paul Durrant Date: Wed, 2 Sep 2015 17:58:36 +0100 Subject: xen-netback: add support for multicast control Xen's PV network protocol includes messages to add/remove ethernet multicast addresses to/from a filter list in the backend. This allows the frontend to request the backend only forward multicast packets which are of interest thus preventing unnecessary noise on the shared ring. The canonical netif header in git://xenbits.xen.org/xen.git specifies the message format (two more XEN_NETIF_EXTRA_TYPEs) so the minimal necessary changes have been pulled into include/xen/interface/io/netif.h. To prevent the frontend from extending the multicast filter list arbitrarily a limit (XEN_NETBK_MCAST_MAX) has been set to 64 entries. This limit is not specified by the protocol and so may change in future. If the limit is reached then the next XEN_NETIF_EXTRA_TYPE_MCAST_ADD sent by the frontend will be failed with NETIF_RSP_ERROR. Signed-off-by: Paul Durrant Cc: Ian Campbell Cc: Wei Liu Acked-by: Wei Liu Signed-off-by: David S. Miller --- drivers/net/xen-netback/interface.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers/net/xen-netback/interface.c') diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 28577a31549d..e7bd63eb2876 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -171,6 +171,13 @@ static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) !xenvif_schedulable(vif)) goto drop; + if (vif->multicast_control && skb->pkt_type == PACKET_MULTICAST) { + struct ethhdr *eth = (struct ethhdr *)skb->data; + + if (!xenvif_mcast_match(vif, eth->h_dest)) + goto drop; + } + cb = XENVIF_RX_CB(skb); cb->expires = jiffies + vif->drain_timeout; @@ -427,6 +434,7 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, vif->num_queues = 0; spin_lock_init(&vif->lock); + INIT_LIST_HEAD(&vif->fe_mcast_addr); dev->netdev_ops = &xenvif_netdev_ops; dev->hw_features = NETIF_F_SG | @@ -661,6 +669,8 @@ void xenvif_disconnect(struct xenvif *vif) xenvif_unmap_frontend_rings(queue); } + + xenvif_mcast_addr_list_free(vif); } /* Reverse the relevant parts of xenvif_init_queue(). -- cgit v1.2.3