[RFC PATCH net-next 6/6 v2] net/sched: act_ct: Add tc recirc id set/del support

[Paul Blakey <paulb@mellanox.com>]

Set or clears (free) the skb tc recirc id extension.
If used with OVS, OVS can clear this recirc id after it reads it.

Signed-off-by: Paul Blakey <paulb@mellanox.com>
---
 include/net/tc_act/tc_ct.h        |  2 ++
 include/uapi/linux/tc_act/tc_ct.h |  2 ++
 net/sched/act_ct.c                | 18 ++++++++++++++++++
 3 files changed, 22 insertions(+)

diff --git a/include/net/tc_act/tc_ct.h b/include/net/tc_act/tc_ct.h
index 4a16375..6ea19d8 100644
--- a/include/net/tc_act/tc_ct.h
+++ b/include/net/tc_act/tc_ct.h
@@ -16,6 +16,8 @@ struct tcf_ct {
 	u32 mark_mask;
 	u16 zone;
 	bool commit;
+	uint32_t set_recirc;
+	bool del_recirc;
 };
 
 #define to_ct(a) ((struct tcf_ct *)a)
diff --git a/include/uapi/linux/tc_act/tc_ct.h b/include/uapi/linux/tc_act/tc_ct.h
index 6dbd771..2279a9b 100644
--- a/include/uapi/linux/tc_act/tc_ct.h
+++ b/include/uapi/linux/tc_act/tc_ct.h
@@ -14,6 +14,8 @@ struct tc_ct {
 	__u32 labels_mask[4];
 	__u32 mark;
 	__u32 mark_mask;
+	uint32_t set_recirc;
+	bool del_recirc;
 	bool commit;
 };
 
diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c
index 61155cc..7822385 100644
--- a/net/sched/act_ct.c
+++ b/net/sched/act_ct.c
@@ -117,6 +117,11 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
 	u_int8_t family;
 	bool cached;
 
+	if (ca->del_recirc) {
+		skb_ext_del(skb, SKB_EXT_TC_RECIRC_ID);
+		return ca->tcf_action;
+	}
+
 	/* The conntrack module expects to be working at L3. */
 	nh_ofs = skb_network_offset(skb);
 	skb_pull_rcsum(skb, nh_ofs);
@@ -243,6 +248,15 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
 	skb_postpush_rcsum(skb, skb->data, nh_ofs);
 
 	spin_unlock(&ca->tcf_lock);
+
+	if (ca->set_recirc) {
+		u32 recirc = ca->set_recirc;
+		uint32_t *recircp = skb_ext_add(skb, SKB_EXT_TC_RECIRC_ID);
+
+		if (recircp)
+			*recircp = recirc;
+	}
+
 	return ca->tcf_action;
 
 drop:
@@ -305,6 +319,8 @@ static int tcf_ct_init(struct net *net, struct nlattr *nla,
 		ci->net = net;
 		ci->commit = parm->commit;
 		ci->zone = parm->zone;
+		ci->set_recirc = parm->set_recirc;
+		ci->del_recirc = parm->del_recirc;
 #if !IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 		if (parm->mark_mask) {
 			NL_SET_ERR_MSG_MOD(extack, "Mark not supported by kernel config");
@@ -378,6 +394,8 @@ static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
 	opt.mark_mask = ci->mark_mask,
 	memcpy(opt.labels, ci->labels, sizeof(opt.labels));
 	memcpy(opt.labels_mask, ci->labels_mask, sizeof(opt.labels_mask));
+	opt.set_recirc = ci->set_recirc;
+	opt.del_recirc = ci->del_recirc;
 
 	if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
 		goto nla_put_failure;
-- 
1.8.3.1