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: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
This commit is contained in:
Paul Blakey 2020-02-16 12:01:24 +02:00 committed by Saeed Mahameed
parent 4371929819
commit af699626ee

View file

@ -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) {