packet: Report fanout status via diag engine

Reported value is the same reported by the FANOUT getsockoption, but
unlike it, the absent fanout setup results in absent nlattr, rather
than in nlattr with zero value. This is done so, since zero fanout
report may mean both -- no fanout, and fanout with both id and type zero.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 19 insertions, 1 deletions

diff --git a/net/packet/internal.h b/net/packet/internal.h
index 2c5fca28b242..44945f6b7252 100644
--- a/net/packet/internal.h
+++ b/net/packet/internal.h
@@ -67,7 +67,25 @@ struct packet_ring_buffer {
 	atomic_t		pending;
 };
 
-struct packet_fanout;
+extern struct mutex fanout_mutex;
+#define PACKET_FANOUT_MAX	256
+
+struct packet_fanout {
+#ifdef CONFIG_NET_NS
+	struct net		*net;
+#endif
+	unsigned int		num_members;
+	u16			id;
+	u8			type;
+	u8			defrag;
+	atomic_t		rr_cur;
+	struct list_head	list;
+	struct sock		*arr[PACKET_FANOUT_MAX];
+	spinlock_t		lock;
+	atomic_t		sk_ref;
+	struct packet_type	prot_hook ____cacheline_aligned_in_smp;
+};
+
 struct packet_sock {
 	/* struct sock has to be the first member of packet_sock */
 	struct sock		sk;