On 29/01/2019 20:12, Marcelo Leitner wrote:
> On Tue, Jan 29, 2019 at 10:02:06AM +0200, Paul Blakey wrote:
>> 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 <pa...@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;
>> };
>
> Have you considered adding a specific action for this? Asking because
> setting recirc_id can be useful outside of ct context too: decap, set
> recirc_id, reclassify.
>
Yes I did, I didn't know if it was overkill, till a use case such as you
suggested arises beside CT.
One thing I'm not sure of is, who will delete the recirc id, it seems
it's freed only via skb_ext_put(skb) at skb_release_head_state()
But I might be missing a del from skb_scrub_packet like nf_reset does.
>>
>> 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
>>
