net: sched: sch_red: Split init and change callbacks

In the following patches, RED will get two qevents. The implementation will
be clearer if the callback for change is not a pure subset of the callback
for init. Split the two and promote attribute parsing to the callbacks
themselves from the common code, because it will be handy there.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c
index 6ace7d7..225ce37 100644 (file)
--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -215,12 +215,11 @@ static const struct nla_policy red_policy[TCA_RED_MAX + 1] = {
        [TCA_RED_FLAGS] = NLA_POLICY_BITFIELD32(TC_RED_SUPPORTED_FLAGS),
 };
 
-static int red_change(struct Qdisc *sch, struct nlattr *opt,
-                     struct netlink_ext_ack *extack)
+static int __red_change(struct Qdisc *sch, struct nlattr **tb,
+                       struct netlink_ext_ack *extack)
 {
        struct Qdisc *old_child = NULL, *child = NULL;
        struct red_sched_data *q = qdisc_priv(sch);
-       struct nlattr *tb[TCA_RED_MAX + 1];
        struct nla_bitfield32 flags_bf;
        struct tc_red_qopt *ctl;
        unsigned char userbits;
@@ -228,14 +227,6 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt,
        int err;
        u32 max_P;
 
-       if (opt == NULL)
-               return -EINVAL;
-
-       err = nla_parse_nested_deprecated(tb, TCA_RED_MAX, opt, red_policy,
-                                         NULL);
-       if (err < 0)
-               return err;
-
        if (tb[TCA_RED_PARMS] == NULL ||
            tb[TCA_RED_STAB] == NULL)
                return -EINVAL;
@@ -323,11 +314,38 @@ static int red_init(struct Qdisc *sch, struct nlattr *opt,
                    struct netlink_ext_ack *extack)
 {
        struct red_sched_data *q = qdisc_priv(sch);
+       struct nlattr *tb[TCA_RED_MAX + 1];
+       int err;
+
+       if (!opt)
+               return -EINVAL;
+
+       err = nla_parse_nested_deprecated(tb, TCA_RED_MAX, opt, red_policy,
+                                         extack);
+       if (err < 0)
+               return err;
 
        q->qdisc = &noop_qdisc;
        q->sch = sch;
        timer_setup(&q->adapt_timer, red_adaptative_timer, 0);
-       return red_change(sch, opt, extack);
+       return __red_change(sch, tb, extack);
+}
+
+static int red_change(struct Qdisc *sch, struct nlattr *opt,
+                     struct netlink_ext_ack *extack)
+{
+       struct nlattr *tb[TCA_RED_MAX + 1];
+       int err;
+
+       if (!opt)
+               return -EINVAL;
+
+       err = nla_parse_nested_deprecated(tb, TCA_RED_MAX, opt, red_policy,
+                                         extack);
+       if (err < 0)
+               return err;
+
+       return __red_change(sch, tb, extack);
 }
 
 static int red_dump_offload_stats(struct Qdisc *sch)