1 files changed, 29 insertions, 4 deletions

diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index 3bfd73344f76..1fa2f903d221 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -22,6 +22,7 @@
 #include <linux/skbuff.h>
 #include <linux/vmalloc.h>
 #include <linux/rtnetlink.h>
+#include <linux/reciprocal_div.h>
 
 #include <net/netlink.h>
 #include <net/pkt_sched.h>
@@ -80,6 +81,10 @@ struct netem_sched_data {
         u32 reorder;
         u32 corrupt;
         u32 rate;
+        s32 packet_overhead;
+        u32 cell_size;
+        u32 cell_size_reciprocal;
+        s32 cell_overhead;
 
         struct crndstate {
                 u32 last;
@@ -299,11 +304,23 @@ static psched_tdiff_t tabledist(psched_tdiff_t mu, psched_tdiff_t sigma,
         return  x / NETEM_DIST_SCALE + (sigma / NETEM_DIST_SCALE) * t + mu;
 }
 
-static psched_time_t packet_len_2_sched_time(unsigned int len, u32 rate)
+static psched_time_t packet_len_2_sched_time(unsigned int len, struct netem_sched_data *q)
 {
-        u64 ticks = (u64)len * NSEC_PER_SEC;
+        u64 ticks;
 
-        do_div(ticks, rate);
+        len += q->packet_overhead;
+
+        if (q->cell_size) {
+                u32 cells = reciprocal_divide(len, q->cell_size_reciprocal);
+
+                if (len > cells * q->cell_size) /* extra cell needed for remainder */
+                        cells++;
+                len = cells * (q->cell_size + q->cell_overhead);
+        }
+
+        ticks = (u64)len * NSEC_PER_SEC;
+
+        do_div(ticks, q->rate);
         return PSCHED_NS2TICKS(ticks);
 }
 
@@ -384,7 +401,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
                 if (q->rate) {
                         struct sk_buff_head *list = &q->qdisc->q;
 
-                        delay += packet_len_2_sched_time(skb->len, q->rate);
+                        delay += packet_len_2_sched_time(skb->len, q);
 
                         if (!skb_queue_empty(list)) {
                                 /*
@@ -568,6 +585,11 @@ static void get_rate(struct Qdisc *sch, const struct nlattr *attr)
         const struct tc_netem_rate *r = nla_data(attr);
 
         q->rate = r->rate;
+        q->packet_overhead = r->packet_overhead;
+        q->cell_size = r->cell_size;
+        if (q->cell_size)
+                q->cell_size_reciprocal = reciprocal_value(q->cell_size);
+        q->cell_overhead = r->cell_overhead;
 }
 
 static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
@@ -909,6 +931,9 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
         NLA_PUT(skb, TCA_NETEM_CORRUPT, sizeof(corrupt), &corrupt);
 
         rate.rate = q->rate;
+        rate.packet_overhead = q->packet_overhead;
+        rate.cell_size = q->cell_size;
+        rate.cell_overhead = q->cell_overhead;
         NLA_PUT(skb, TCA_NETEM_RATE, sizeof(rate), &rate);
 
         if (dump_loss_model(q, skb) != 0)