net/sched: cls_flower: Add support to handle first frag as match field

Allow setting firstfrag as matching option in tc flower classifier.

 # tc filter add dev eth0 protocol ip parent ffff: \
     flower indev eth0 \
        ip_flags firstfrag
     action mirred egress redirect dev eth1
Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/pkt_cls.h

@@ -475,6 +475,7 @@ enum {
 
 enum {
 	TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT = (1 << 0),
+	TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST = (1 << 1),
 };
 
 /* Match-all classifier */

net/sched/cls_flower.c

@@ -511,6 +511,9 @@ static int fl_set_key_flags(struct nlattr **tb,
 
 	fl_set_key_flag(key, mask, flags_key, flags_mask,
 			TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT, FLOW_DIS_IS_FRAGMENT);
+	fl_set_key_flag(key, mask, flags_key, flags_mask,
+			TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST,
+			FLOW_DIS_FIRST_FRAG);
 
 	return 0;
 }
@@ -1130,6 +1133,9 @@ static int fl_dump_key_flags(struct sk_buff *skb, u32 flags_key, u32 flags_mask)
 
 	fl_get_key_flag(flags_key, flags_mask, &key, &mask,
 			TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT, FLOW_DIS_IS_FRAGMENT);
+	fl_get_key_flag(flags_key, flags_mask, &key, &mask,
+			TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST,
+			FLOW_DIS_FIRST_FRAG);
 
 	_key = cpu_to_be32(key);
 	_mask = cpu_to_be32(mask);