net/8021q/vlan_core.c

   1 #include <linux/skbuff.h>
   2 #include <linux/netdevice.h>
   3 #include <linux/if_vlan.h>
   4 #include <linux/netpoll.h>
   5 #include "vlan.h"
   6
   7 /* VLAN rx hw acceleration helper.  This acts like netif_{rx,receive_skb}(). */
   8 int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
   9                       u16 vlan_tci, int polling)
  10 {
  11         struct net_device *vlan_dev;
  12         u16 vlan_id;
  13
  14         if (netpoll_rx(skb))
  15                 return NET_RX_DROP;
  16
  17         if (skb_bond_should_drop(skb, ACCESS_ONCE(skb->dev->master)))
  18                 skb->deliver_no_wcard = 1;
  19
  20         skb->skb_iif = skb->dev->ifindex;
  21         __vlan_hwaccel_put_tag(skb, vlan_tci);
  22         vlan_id = vlan_tci & VLAN_VID_MASK;
  23         vlan_dev = vlan_group_get_device(grp, vlan_id);
  24
  25         if (vlan_dev)
  26                 skb->dev = vlan_dev;
  27         else if (vlan_id) {
  28                 if (!(skb->dev->flags & IFF_PROMISC))
  29                         goto drop;
  30                 skb->pkt_type = PACKET_OTHERHOST;
  31         }
  32
  33         return polling ? netif_receive_skb(skb) : netif_rx(skb);
  34
  35 drop:
  36         atomic_long_inc(&skb->dev->rx_dropped);
  37         dev_kfree_skb_any(skb);
  38         return NET_RX_DROP;
  39 }
  40 EXPORT_SYMBOL(__vlan_hwaccel_rx);
  41
  42 void vlan_hwaccel_do_receive(struct sk_buff *skb)
  43 {
  44         struct net_device *dev = skb->dev;
  45         struct vlan_rx_stats     *rx_stats;
  46
  47         skb->dev = vlan_dev_real_dev(dev);
  48         netif_nit_deliver(skb);
  49
  50         skb->dev = dev;
  51         skb->priority = vlan_get_ingress_priority(dev, skb->vlan_tci);
  52         skb->vlan_tci = 0;
  53
  54         rx_stats = this_cpu_ptr(vlan_dev_info(dev)->vlan_rx_stats);
  55
  56         u64_stats_update_begin(&rx_stats->syncp);
  57         rx_stats->rx_packets++;
  58         rx_stats->rx_bytes += skb->len;
  59
  60         switch (skb->pkt_type) {
  61         case PACKET_BROADCAST:
  62                 break;
  63         case PACKET_MULTICAST:
  64                 rx_stats->rx_multicast++;
  65                 break;
  66         case PACKET_OTHERHOST:
  67                 /* Our lower layer thinks this is not local, let's make sure.
  68                  * This allows the VLAN to have a different MAC than the
  69                  * underlying device, and still route correctly. */
  70                 if (!compare_ether_addr(eth_hdr(skb)->h_dest,
  71                                         dev->dev_addr))
  72                         skb->pkt_type = PACKET_HOST;
  73                 break;
  74         }
  75         u64_stats_update_end(&rx_stats->syncp);
  76 }
  77
  78 struct net_device *vlan_dev_real_dev(const struct net_device *dev)
  79 {
  80         return vlan_dev_info(dev)->real_dev;
  81 }
  82 EXPORT_SYMBOL(vlan_dev_real_dev);
  83
  84 u16 vlan_dev_vlan_id(const struct net_device *dev)
  85 {
  86         return vlan_dev_info(dev)->vlan_id;
  87 }
  88 EXPORT_SYMBOL(vlan_dev_vlan_id);
  89
  90 static gro_result_t
  91 vlan_gro_common(struct napi_struct *napi, struct vlan_group *grp,
  92                 unsigned int vlan_tci, struct sk_buff *skb)
  93 {
  94         struct sk_buff *p;
  95         struct net_device *vlan_dev;
  96         u16 vlan_id;
  97
  98         if (skb_bond_should_drop(skb, ACCESS_ONCE(skb->dev->master)))
  99                 skb->deliver_no_wcard = 1;
 100
 101         skb->skb_iif = skb->dev->ifindex;
 102         __vlan_hwaccel_put_tag(skb, vlan_tci);
 103         vlan_id = vlan_tci & VLAN_VID_MASK;
 104         vlan_dev = vlan_group_get_device(grp, vlan_id);
 105
 106         if (vlan_dev)
 107                 skb->dev = vlan_dev;
 108         else if (vlan_id) {
 109                 if (!(skb->dev->flags & IFF_PROMISC))
 110                         goto drop;
 111                 skb->pkt_type = PACKET_OTHERHOST;
 112         }
 113
 114         for (p = napi->gro_list; p; p = p->next) {
 115                 unsigned long diffs;
 116
 117                 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
 118                 diffs |= compare_ether_header(skb_mac_header(p),
 119                                               skb_gro_mac_header(skb));
 120                 NAPI_GRO_CB(p)->same_flow = !diffs;
 121                 NAPI_GRO_CB(p)->flush = 0;
 122         }
 123
 124         return dev_gro_receive(napi, skb);
 125
 126 drop:
 127         atomic_long_inc(&skb->dev->rx_dropped);
 128         return GRO_DROP;
 129 }
 130
 131 gro_result_t vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
 132                               unsigned int vlan_tci, struct sk_buff *skb)
 133 {
 134         if (netpoll_rx_on(skb))
 135                 return vlan_hwaccel_receive_skb(skb, grp, vlan_tci)
 136                         ? GRO_DROP : GRO_NORMAL;
 137
 138         skb_gro_reset_offset(skb);
 139
 140         return napi_skb_finish(vlan_gro_common(napi, grp, vlan_tci, skb), skb);
 141 }
 142 EXPORT_SYMBOL(vlan_gro_receive);
 143
 144 gro_result_t vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
 145                             unsigned int vlan_tci)
 146 {
 147         struct sk_buff *skb = napi_frags_skb(napi);
 148
 149         if (!skb)
 150                 return GRO_DROP;
 151
 152         if (netpoll_rx_on(skb)) {
 153                 skb->protocol = eth_type_trans(skb, skb->dev);
 154                 return vlan_hwaccel_receive_skb(skb, grp, vlan_tci)
 155                         ? GRO_DROP : GRO_NORMAL;
 156         }
 157
 158         return napi_frags_finish(napi, skb,
 159                                  vlan_gro_common(napi, grp, vlan_tci, skb));
 160 }
 161 EXPORT_SYMBOL(vlan_gro_frags);