packet: Add fanout support.
Fanouts allow packet capturing to be demuxed to a set of AF_PACKET
sockets. Two fanout policies are implemented:
1) Hashing based upon skb->rxhash
2) Pure round-robin
An AF_PACKET socket must be fully bound before it tries to add itself
to a fanout. All AF_PACKET sockets trying to join the same fanout
must all have the same bind settings.
Fanouts are identified (within a network namespace) by a 16-bit ID.
The first socket to try to add itself to a fanout with a particular
ID, creates that fanout. When the last socket leaves the fanout
(which happens only when the socket is closed), that fanout is
destroyed.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/if_packet.h b/include/linux/if_packet.h
index 7b31863..1efa1cb 100644
--- a/include/linux/if_packet.h
+++ b/include/linux/if_packet.h
@@ -49,6 +49,10 @@
#define PACKET_VNET_HDR 15
#define PACKET_TX_TIMESTAMP 16
#define PACKET_TIMESTAMP 17
+#define PACKET_FANOUT 18
+
+#define PACKET_FANOUT_HASH 0
+#define PACKET_FANOUT_LB 1
struct tpacket_stats {
unsigned int tp_packets;