Subject: Re: [PATCH net-next,v3 04/12] cls_api: add translator to flow_action representation

From: Marcelo Ricardo Leitner <[email-masked]>
Date: Wed, 21 Nov 2018 19:15:41 -0200

On Wed, Nov 21, 2018 at 03:51:24AM +0100, Pablo Neira Ayuso wrote:
> This patch implements a new function to translate from native TC action
> to the new flow_action representation. Moreover, this patch also updates
> cls_flower to use this new function.
> 
> Signed-off-by: Pablo Neira Ayuso <[email-masked]>
> ---
> v3: add tcf_exts_num_actions() and pass it to flow_rule_alloc() to calculate
>     the size of the array of actions.
> 
>  include/net/pkt_cls.h  |   5 +++
>  net/sched/cls_api.c    | 116 +++++++++++++++++++++++++++++++++++++++++++++++++
>  net/sched/cls_flower.c |  21 +++++++--
>  3 files changed, 139 insertions(+), 3 deletions(-)
> 
> diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
> index 359876ee32be..abb035f84321 100644
> --- a/include/net/pkt_cls.h
> +++ b/include/net/pkt_cls.h
> @@ -620,6 +620,11 @@ tcf_match_indev(struct sk_buff *skb, int ifindex)
>  }
>  #endif /* CONFIG_NET_CLS_IND */
>  
> +unsigned int tcf_exts_num_actions(struct tcf_exts *exts);
> +
> +int tc_setup_flow_action(struct flow_action *flow_action,
> +			 const struct tcf_exts *exts);
> +
>  int tc_setup_cb_call(struct tcf_block *block, struct tcf_exts *exts,
>  		     enum tc_setup_type type, void *type_data, bool err_stop);
>  
> diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
> index d92f44ac4c39..6f8b953dabc4 100644
> --- a/net/sched/cls_api.c
> +++ b/net/sched/cls_api.c
> @@ -31,6 +31,14 @@
>  #include <net/netlink.h>
>  #include <net/pkt_sched.h>
>  #include <net/pkt_cls.h>
> +#include <net/tc_act/tc_mirred.h>
> +#include <net/tc_act/tc_vlan.h>
> +#include <net/tc_act/tc_tunnel_key.h>
> +#include <net/tc_act/tc_pedit.h>
> +#include <net/tc_act/tc_csum.h>
> +#include <net/tc_act/tc_gact.h>
> +#include <net/tc_act/tc_skbedit.h>
> +#include <net/tc_act/tc_mirred.h>
>  
>  extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
>  
> @@ -2567,6 +2575,114 @@ int tc_setup_cb_call(struct tcf_block *block, struct tcf_exts *exts,
>  }
>  EXPORT_SYMBOL(tc_setup_cb_call);
>  
> +int tc_setup_flow_action(struct flow_action *flow_action,
> +			 const struct tcf_exts *exts)
> +{
> +	const struct tc_action *act;
> +	int i, j, k;
> +
> +	if (!exts)
> +		return 0;
> +
> +	j = 0;
> +	tcf_exts_for_each_action(i, act, exts) {
> +		struct flow_action_entry *key;
> +
> +		key = &flow_action->entries[j];
> +		if (is_tcf_gact_ok(act)) {
> +			key->id = FLOW_ACTION_ACCEPT;
> +		} else if (is_tcf_gact_shot(act)) {
> +			key->id = FLOW_ACTION_DROP;
> +		} else if (is_tcf_gact_trap(act)) {
> +			key->id = FLOW_ACTION_TRAP;
> +		} else if (is_tcf_gact_goto_chain(act)) {
> +			key->id = FLOW_ACTION_GOTO;
> +			key->chain_index = tcf_gact_goto_chain_index(act);
> +		} else if (is_tcf_mirred_egress_redirect(act)) {
> +			key->id = FLOW_ACTION_REDIRECT;
> +			key->dev = tcf_mirred_dev(act);
> +		} else if (is_tcf_mirred_egress_mirror(act)) {
> +			key->id = FLOW_ACTION_MIRRED;
> +			key->dev = tcf_mirred_dev(act);
> +		} else if (is_tcf_vlan(act)) {
> +			switch (tcf_vlan_action(act)) {
> +			case TCA_VLAN_ACT_PUSH:
> +				key->id = FLOW_ACTION_VLAN_PUSH;
> +				key->vlan.vid = tcf_vlan_push_vid(act);
> +				key->vlan.proto = tcf_vlan_push_proto(act);
> +				key->vlan.prio = tcf_vlan_push_prio(act);
> +				break;
> +			case TCA_VLAN_ACT_POP:
> +				key->id = FLOW_ACTION_VLAN_POP;
> +				break;
> +			case TCA_VLAN_ACT_MODIFY:
> +				key->id = FLOW_ACTION_VLAN_MANGLE;
> +				key->vlan.vid = tcf_vlan_push_vid(act);
> +				key->vlan.proto = tcf_vlan_push_proto(act);
> +				key->vlan.prio = tcf_vlan_push_prio(act);
> +				break;
> +			default:
> +				goto err_out;
> +			}
> +		} else if (is_tcf_tunnel_set(act)) {
> +			key->id = FLOW_ACTION_TUNNEL_ENCAP;
> +			key->tunnel = tcf_tunnel_info(act);
> +		} else if (is_tcf_tunnel_release(act)) {
> +			key->id = FLOW_ACTION_TUNNEL_DECAP;
> +			key->tunnel = tcf_tunnel_info(act);
> +		} else if (is_tcf_pedit(act)) {
> +			for (k = 0; k < tcf_pedit_nkeys(act); k++) {
> +				switch (tcf_pedit_cmd(act, k)) {
> +				case TCA_PEDIT_KEY_EX_CMD_SET:
> +					key->id = FLOW_ACTION_MANGLE;
> +					break;
> +				case TCA_PEDIT_KEY_EX_CMD_ADD:
> +					key->id = FLOW_ACTION_ADD;
> +					break;
> +				default:
> +					goto err_out;
> +				}
> +				key->mangle.htype = tcf_pedit_htype(act, k);
> +				key->mangle.mask = tcf_pedit_mask(act, k);
> +				key->mangle.val = tcf_pedit_val(act, k);
> +				key->mangle.offset = tcf_pedit_offset(act, k);
> +				key = &flow_action->entries[++j];
> +			}
> +		} else if (is_tcf_csum(act)) {
> +			key->id = FLOW_ACTION_CSUM;
> +			key->csum_flags = tcf_csum_update_flags(act);
> +		} else if (is_tcf_skbedit_mark(act)) {
> +			key->id = FLOW_ACTION_MARK;
> +			key->mark = tcf_skbedit_mark(act);
> +		} else {
> +			goto err_out;
> +		}
> +
> +		if (!is_tcf_pedit(act))
> +			j++;
> +	}
> +	return 0;
> +err_out:
> +	return -EOPNOTSUPP;
> +}
> +EXPORT_SYMBOL(tc_setup_flow_action);
> +
> +unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
> +{
> +	unsigned int num_acts = 0;
> +	struct tc_action *act;
> +	int i;
> +
> +	tcf_exts_for_each_action(i, act, exts) {
> +		if (is_tcf_pedit(act))
> +			num_acts += tcf_pedit_nkeys(act);
> +		else
> +			num_acts++;
> +	}
> +	return num_acts;
> +}
> +EXPORT_SYMBOL(tcf_exts_num_actions);
> +
>  static __net_init int tcf_net_init(struct net *net)
>  {
>  	struct tcf_net *tn = net_generic(net, tcf_net_id);
> diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
> index d2971fbfc3d9..8898943b8ee6 100644
> --- a/net/sched/cls_flower.c
> +++ b/net/sched/cls_flower.c
> @@ -382,7 +382,7 @@ static int fl_hw_replace_filter(struct tcf_proto *tp,
>  	bool skip_sw = tc_skip_sw(f->flags);
>  	int err;
>  
> -	cls_flower.rule = flow_rule_alloc();
> +	cls_flower.rule = flow_rule_alloc(tcf_exts_num_actions(&f->exts));

As previous patch did:
-struct flow_rule *flow_rule_alloc(void);
+struct flow_rule *flow_rule_alloc(unsigned int num_actions);
the build is broken without this change (bisect-ability).
(applies to similar lines too)