net_sched: refactor TC action init API

TC action ->init() API has 10 parameters, it becomes harder
to read. Some of them are just boolean and can be replaced
by flags. Similarly for the internal API tcf_action_init()
and tcf_exts_validate().

This patch converts them to flags and fold them into
the upper 16 bits of "flags", whose lower 16 bits are still
reserved for user-space. More specifically, the following
kernel flags are introduced:

TCA_ACT_FLAGS_POLICE replace 'name' in a few contexts, to
distinguish whether it is compatible with policer.

TCA_ACT_FLAGS_BIND replaces 'bind', to indicate whether
this action is bound to a filter.

TCA_ACT_FLAGS_REPLACE  replaces 'ovr' in most contexts,
means we are replacing an existing action.

TCA_ACT_FLAGS_NO_RTNL replaces 'rtnl_held' but has the
opposite meaning, because we still hold RTNL in most
cases.

The only user-space flag TCA_ACT_FLAGS_NO_PERCPU_STATS is
untouched and still stored as before.

I have tested this patch with tdc and I do not see any
failure related to this patch.

Tested-by: Vlad Buslov <vladbu@nvidia.com>
Acked-by: Jamal Hadi Salim<jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 3 deletions

diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c
index 6a0c16e4351d..230501eb9e06 100644
--- a/net/sched/act_sample.c
+++ b/net/sched/act_sample.c
@@ -34,11 +34,12 @@ static const struct nla_policy sample_policy[TCA_SAMPLE_MAX + 1] = {
 };
 
 static int tcf_sample_init(struct net *net, struct nlattr *nla,
-			   struct nlattr *est, struct tc_action **a, int ovr,
-			   int bind, bool rtnl_held, struct tcf_proto *tp,
+			   struct nlattr *est, struct tc_action **a,
+			   struct tcf_proto *tp,
 			   u32 flags, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, sample_net_id);
+	bool bind = flags & TCA_ACT_FLAGS_BIND;
 	struct nlattr *tb[TCA_SAMPLE_MAX + 1];
 	struct psample_group *psample_group;
 	u32 psample_group_num, rate, index;
@@ -75,7 +76,7 @@ static int tcf_sample_init(struct net *net, struct nlattr *nla,
 			return ret;
 		}
 		ret = ACT_P_CREATED;
-	} else if (!ovr) {
+	} else if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
 		tcf_idr_release(*a, bind);
 		return -EEXIST;
 	}