netem: add 64bit rates support

netem support 64bit rates start from linux-3.13.
Add 64bit rates support in tc tools.

tc qdisc show dev eth0
qdisc netem 1: dev eth4 root refcnt 2 limit 1000 rate 35Gbit

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Acked-by: Eric Dumazet <edumazet@google.com>
diff --git a/tc/q_netem.c b/tc/q_netem.c
index 9dd8712..946007c 100644
--- a/tc/q_netem.c
+++ b/tc/q_netem.c
@@ -183,6 +183,7 @@
 	__s16 *dist_data = NULL;
 	__u16 loss_type = NETEM_LOSS_UNSPEC;
 	int present[__TCA_NETEM_MAX];
+	__u64 rate64 = 0;
 
 	memset(&cor, 0, sizeof(cor));
 	memset(&reorder, 0, sizeof(reorder));
@@ -391,7 +392,7 @@
 		} else if (matches(*argv, "rate") == 0) {
 			++present[TCA_NETEM_RATE];
 			NEXT_ARG();
-			if (get_rate(&rate.rate, *argv)) {
+			if (get_rate64(&rate64, *argv)) {
 				explain1("rate");
 				return -1;
 			}
@@ -496,9 +497,18 @@
 		addattr_nest_end(n, start);
 	}
 
-	if (present[TCA_NETEM_RATE] &&
-	    addattr_l(n, 1024, TCA_NETEM_RATE, &rate, sizeof(rate)) < 0)
-		return -1;
+	if (present[TCA_NETEM_RATE]) {
+		if (rate64 >= (1ULL << 32)) {
+			if (addattr_l(n, 1024,
+				      TCA_NETEM_RATE64, &rate64, sizeof(rate64)) < 0)
+				return -1;
+			rate.rate = ~0U;
+		} else {
+			rate.rate = rate64;
+		}
+		if (addattr_l(n, 1024, TCA_NETEM_RATE, &rate, sizeof(rate)) < 0)
+			return -1;
+	}
 
 	if (dist_data) {
 		if (addattr_l(n, MAX_DIST * sizeof(dist_data[0]),
@@ -522,6 +532,7 @@
 	struct tc_netem_qopt qopt;
 	const struct tc_netem_rate *rate = NULL;
 	int len = RTA_PAYLOAD(opt) - sizeof(qopt);
+	__u64 rate64 = 0;
 	SPRINT_BUF(b1);
 
 	if (opt == NULL)
@@ -572,6 +583,11 @@
 				return -1;
 			ecn = RTA_DATA(tb[TCA_NETEM_ECN]);
 		}
+		if (tb[TCA_NETEM_RATE64]) {
+			if (RTA_PAYLOAD(tb[TCA_NETEM_RATE64]) < sizeof(rate64))
+				return -1;
+			rate64 = rta_getattr_u64(tb[TCA_NETEM_RATE64]);
+		}
 	}
 
 	fprintf(f, "limit %d", qopt.limit);
@@ -632,7 +648,10 @@
 	}
 
 	if (rate && rate->rate) {
-		fprintf(f, " rate %s", sprint_rate(rate->rate, b1));
+		if (rate64)
+			fprintf(f, " rate %s", sprint_rate(rate64, b1));
+		else
+			fprintf(f, " rate %s", sprint_rate(rate->rate, b1));
 		if (rate->packet_overhead)
 			fprintf(f, " packetoverhead %d", rate->packet_overhead);
 		if (rate->cell_size)