cls_cgroup: fix an oops when removing a cgroup

[safe/jmp/linux-2.6] / net / sched / sch_cbq.c

diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
index 03e389e..9e43ed9 100644 (file)
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -405,40 +405,6 @@ cbq_enqueue(struct sk_buff *skb, struct Qdisc *sch)
        return ret;
 }
 
-static int
-cbq_requeue(struct sk_buff *skb, struct Qdisc *sch)
-{
-       struct cbq_sched_data *q = qdisc_priv(sch);
-       struct cbq_class *cl;
-       int ret;
-
-       if ((cl = q->tx_class) == NULL) {
-               kfree_skb(skb);
-               sch->qstats.drops++;
-               return NET_XMIT_CN;
-       }
-       q->tx_class = NULL;
-
-       cbq_mark_toplevel(q, cl);
-
-#ifdef CONFIG_NET_CLS_ACT
-       q->rx_class = cl;
-       cl->q->__parent = sch;
-#endif
-       if ((ret = cl->q->ops->requeue(skb, cl->q)) == 0) {
-               sch->q.qlen++;
-               sch->qstats.requeues++;
-               if (!cl->next_alive)
-                       cbq_activate_class(cl);
-               return 0;
-       }
-       if (net_xmit_drop_count(ret)) {
-               sch->qstats.drops++;
-               cl->qstats.drops++;
-       }
-       return ret;
-}
-
 /* Overlimit actions */
 
 /* TC_CBQ_OVL_CLASSIC: (default) penalize leaf class by adding offtime */
@@ -1669,7 +1635,8 @@ static int cbq_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
 #endif
                }
                sch_tree_lock(sch);
-               *old = xchg(&cl->q, new);
+               *old = cl->q;
+               cl->q = new;
                qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
                qdisc_reset(*old);
                sch_tree_unlock(sch);
@@ -1798,11 +1765,23 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
                }
 
                if (tb[TCA_CBQ_RATE]) {
-                       rtab = qdisc_get_rtab(nla_data(tb[TCA_CBQ_RATE]), tb[TCA_CBQ_RTAB]);
+                       rtab = qdisc_get_rtab(nla_data(tb[TCA_CBQ_RATE]),
+                                             tb[TCA_CBQ_RTAB]);
                        if (rtab == NULL)
                                return -EINVAL;
                }
 
+               if (tca[TCA_RATE]) {
+                       err = gen_replace_estimator(&cl->bstats, &cl->rate_est,
+                                                   qdisc_root_sleeping_lock(sch),
+                                                   tca[TCA_RATE]);
+                       if (err) {
+                               if (rtab)
+                                       qdisc_put_rtab(rtab);
+                               return err;
+                       }
+               }
+
                /* Change class parameters */
                sch_tree_lock(sch);
 
@@ -1810,8 +1789,8 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
                        cbq_deactivate_class(cl);
 
                if (rtab) {
-                       rtab = xchg(&cl->R_tab, rtab);
-                       qdisc_put_rtab(rtab);
+                       qdisc_put_rtab(cl->R_tab);
+                       cl->R_tab = rtab;
                }
 
                if (tb[TCA_CBQ_LSSOPT])
@@ -1838,10 +1817,6 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
 
                sch_tree_unlock(sch);
 
-               if (tca[TCA_RATE])
-                       gen_replace_estimator(&cl->bstats, &cl->rate_est,
-                                             qdisc_root_sleeping_lock(sch),
-                                             tca[TCA_RATE]);
                return 0;
        }
 
@@ -1888,6 +1863,17 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
        cl = kzalloc(sizeof(*cl), GFP_KERNEL);
        if (cl == NULL)
                goto failure;
+
+       if (tca[TCA_RATE]) {
+               err = gen_new_estimator(&cl->bstats, &cl->rate_est,
+                                       qdisc_root_sleeping_lock(sch),
+                                       tca[TCA_RATE]);
+               if (err) {
+                       kfree(cl);
+                       goto failure;
+               }
+       }
+
        cl->R_tab = rtab;
        rtab = NULL;
        cl->refcnt = 1;
@@ -1929,10 +1915,6 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
 
        qdisc_class_hash_grow(sch, &q->clhash);
 
-       if (tca[TCA_RATE])
-               gen_new_estimator(&cl->bstats, &cl->rate_est,
-                                 qdisc_root_sleeping_lock(sch), tca[TCA_RATE]);
-
        *arg = (unsigned long)cl;
        return 0;
 
@@ -2066,7 +2048,7 @@ static struct Qdisc_ops cbq_qdisc_ops __read_mostly = {
        .priv_size      =       sizeof(struct cbq_sched_data),
        .enqueue        =       cbq_enqueue,
        .dequeue        =       cbq_dequeue,
-       .requeue        =       cbq_requeue,
+       .peek           =       qdisc_peek_dequeued,
        .drop           =       cbq_drop,
        .init           =       cbq_init,
        .reset          =       cbq_reset,