net: sched: act_gact: remove dependency on rtnl lock

Use tcf spinlock to protect gact action private state from concurrent
modification during dump and init. Remove rtnl assertion that is no longer
necessary.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index 661b72b9147d52d320f094b91b7392488c1f25c2..bfccd34a3968b6487094e33fc64643d88ad7b85d 100644 (file)
--- a/net/sched/act_gact.c
+++ b/net/sched/act_gact.c
@@ -113,7 +113,7 @@ static int tcf_gact_init(struct net *net, struct nlattr *nla,
 
        gact = to_gact(*a);
 
-       ASSERT_RTNL();
+       spin_lock(&gact->tcf_lock);
        gact->tcf_action = parm->action;
 #ifdef CONFIG_GACT_PROB
        if (p_parm) {
@@ -126,6 +126,8 @@ static int tcf_gact_init(struct net *net, struct nlattr *nla,
                gact->tcfg_ptype   = p_parm->ptype;
        }
 #endif
+       spin_unlock(&gact->tcf_lock);
+
        if (ret == ACT_P_CREATED)
                tcf_idr_insert(tn, *a);
        return ret;
@@ -178,10 +180,11 @@ static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a,
                .index   = gact->tcf_index,
                .refcnt  = refcount_read(&gact->tcf_refcnt) - ref,
                .bindcnt = atomic_read(&gact->tcf_bindcnt) - bind,
-               .action  = gact->tcf_action,
        };
        struct tcf_t t;
 
+       spin_lock(&gact->tcf_lock);
+       opt.action = gact->tcf_action;
        if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt))
                goto nla_put_failure;
 #ifdef CONFIG_GACT_PROB
@@ -199,9 +202,12 @@ static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a,
        tcf_tm_dump(&t, &gact->tcf_tm);
        if (nla_put_64bit(skb, TCA_GACT_TM, sizeof(t), &t, TCA_GACT_PAD))
                goto nla_put_failure;
+       spin_unlock(&gact->tcf_lock);
+
        return skb->len;
 
 nla_put_failure:
+       spin_unlock(&gact->tcf_lock);
        nlmsg_trim(skb, b);
        return -1;
 }