net/sched: Retire ipt action

The tc ipt action was intended to run all netfilter/iptables target.
Unfortunately it has not benefitted over the years from proper updates when
netfilter changes, and for that reason it has remained rudimentary.
Pinging a bunch of people that i was aware were using this indicates that
removing it wont affect them.
Retire it to reduce maintenance efforts. Buh-bye.

Reviewed-by: Victor Noguiera <[email protected]>
Reviewed-by: Pedro Tammela <[email protected]>
Signed-off-by: Jamal Hadi Salim <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: jhsmt

include/net/tc_act/tc_ipt.h

@@ -117,10 +117,6 @@ static inline int tc_act(struct sk_buff *skb, const struct tc_action *a,
 	if (a->ops->act == tcf_ife_act)
 		return tcf_ife_act(skb, a, res);
 #endif
-#if IS_BUILTIN(CONFIG_NET_ACT_IPT)
-	if (a->ops->act == tcf_ipt_act)
-		return tcf_ipt_act(skb, a, res);
-#endif
 #if IS_BUILTIN(CONFIG_NET_ACT_SIMP)
 	if (a->ops->act == tcf_simp_act)
 		return tcf_simp_act(skb, a, res);

include/net/tc_wrapper.h

@@ -99,7 +99,7 @@ enum {
  * versions.
  */
 #define TCA_ACT_GACT 5
-#define TCA_ACT_IPT 6
+#define TCA_ACT_IPT 6 /* obsoleted, can be reused */
 #define TCA_ACT_PEDIT 7
 #define TCA_ACT_MIRRED 8
 #define TCA_ACT_NAT 9
@@ -120,7 +120,7 @@ enum tca_id {
 	TCA_ID_UNSPEC = 0,
 	TCA_ID_POLICE = 1,
 	TCA_ID_GACT = TCA_ACT_GACT,
-	TCA_ID_IPT = TCA_ACT_IPT,
+	TCA_ID_IPT = TCA_ACT_IPT, /* Obsoleted, can be reused */
 	TCA_ID_PEDIT = TCA_ACT_PEDIT,
 	TCA_ID_MIRRED = TCA_ACT_MIRRED,
 	TCA_ID_NAT = TCA_ACT_NAT,

include/uapi/linux/pkt_cls.h

@@ -13,7 +13,6 @@ obj-$(CONFIG_NET_ACT_POLICE)	+= act_police.o
 obj-$(CONFIG_NET_ACT_GACT)	+= act_gact.o
 obj-$(CONFIG_NET_ACT_MIRRED)	+= act_mirred.o
 obj-$(CONFIG_NET_ACT_SAMPLE)	+= act_sample.o
-obj-$(CONFIG_NET_ACT_IPT)	+= act_ipt.o
 obj-$(CONFIG_NET_ACT_NAT)	+= act_nat.o
 obj-$(CONFIG_NET_ACT_PEDIT)	+= act_pedit.o
 obj-$(CONFIG_NET_ACT_SIMP)	+= act_simple.o