filter: Add SKF_AD_QUEUE instruction

It can help being able to filter packets on their queue_mapping.

If filter performance is not good, we could add a "numqueue" field
in struct packet_type, so that netif_nit_deliver() and other functions
can directly ignore packets with not expected queue number.

Lets experiment this simple filter extension first.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 5 insertions, 1 deletions

diff --git a/include/linux/filter.h b/include/linux/filter.h
index 909193e25395..bb3b4352978a 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -124,7 +124,8 @@ struct sock_fprog	/* Required for SO_ATTACH_FILTER. */
 #define SKF_AD_NLATTR   12
 #define SKF_AD_NLATTR_NEST      16
 #define SKF_AD_MARK     20
-#define SKF_AD_MAX      24
+#define SKF_AD_QUEUE    24
+#define SKF_AD_MAX      28
 #define SKF_NET_OFF   (-0x100000)
 #define SKF_LL_OFF    (-0x200000)
 
diff --git a/net/core/filter.c b/net/core/filter.c
index e3987e1d4839..08db7b9143a3 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -306,6 +306,9 @@ load_b:
                 case SKF_AD_MARK:
                         A = skb->mark;
                         continue;
+                case SKF_AD_QUEUE:
+                        A = skb->queue_mapping;
+                        continue;
                 case SKF_AD_NLATTR: {
                         struct nlattr *nla;