Commit af699626 authored by Paul Blakey's avatar Paul Blakey Committed by Saeed Mahameed
Browse files

net: sched: Support specifying a starting chain via tc skb ext 



Set the starting chain from the tc skb ext chain value. Once we read
the tc skb ext, delete it, so cloned/redirect packets won't inherit it.

In order to lookup a chain by the chain index on the ingress block
at ingress classification, provide a lookup function.

Co-developed-by: default avatarVlad Buslov <vladbu@mellanox.com>
Signed-off-by: default avatarVlad Buslov <vladbu@mellanox.com>
Signed-off-by: default avatarPaul Blakey <paulb@mellanox.com>
Reviewed-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@mellanox.com>
parent 43719298

net/sched/cls_api.c

+35 −4
Original line number Diff line number Diff line
@@ -454,6 +454,20 @@ static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block, 
	return NULL;

}



#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)

static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block,

					      u32 chain_index)

{

	struct tcf_chain *chain;



	list_for_each_entry_rcu(chain, &block->chain_list, list) {

		if (chain->index == chain_index)

			return chain;

	}

	return NULL;

}

#endif



static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,

			   u32 seq, u16 flags, int event, bool unicast);
@@ -1562,13 +1576,13 @@ static int tcf_block_setup(struct tcf_block *block, 
 */

static inline int __tcf_classify(struct sk_buff *skb,

				 const struct tcf_proto *tp,

				 const struct tcf_proto *orig_tp,

				 struct tcf_result *res,

				 bool compat_mode,

				 u32 *last_executed_chain)

{

#ifdef CONFIG_NET_CLS_ACT

	const int max_reclassify_loop = 4;

	const struct tcf_proto *orig_tp = tp;

	const struct tcf_proto *first_tp;

	int limit = 0;
@@ -1619,7 +1633,7 @@ int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp, 
{

	u32 last_executed_chain = 0;



	return __tcf_classify(skb, tp, res, compat_mode,

	return __tcf_classify(skb, tp, tp, res, compat_mode,

			      &last_executed_chain);

}

EXPORT_SYMBOL(tcf_classify);
@@ -1632,14 +1646,31 @@ int tcf_classify_ingress(struct sk_buff *skb, 
#if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)

	u32 last_executed_chain = 0;



	return __tcf_classify(skb, tp, res, compat_mode,

	return __tcf_classify(skb, tp, tp, res, compat_mode,

			      &last_executed_chain);

#else

	u32 last_executed_chain = tp ? tp->chain->index : 0;

	const struct tcf_proto *orig_tp = tp;

	struct tc_skb_ext *ext;

	int ret;



	ret = __tcf_classify(skb, tp, res, compat_mode, &last_executed_chain);

	ext = skb_ext_find(skb, TC_SKB_EXT);



	if (ext && ext->chain) {

		struct tcf_chain *fchain;



		fchain = tcf_chain_lookup_rcu(ingress_block, ext->chain);

		if (!fchain)

			return TC_ACT_SHOT;



		/* Consume, so cloned/redirect skbs won't inherit ext */

		skb_ext_del(skb, TC_SKB_EXT);



		tp = rcu_dereference_bh(fchain->filter_chain);

	}



	ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode,

			     &last_executed_chain);



	/* If we missed on some chain */

	if (ret == TC_ACT_UNSPEC && last_executed_chain) {

CRA Git | Maintained and supported by SUSTech CRA and CCSE