net_sched: htb: support of 64bit rates

HTB already can deal with 64bit rates, we only have to add two new
attributes so that tc can use them to break the current 32bit ABI
barrier.

TCA_HTB_RATE64 : class rate  (in bytes per second)
TCA_HTB_CEIL64 : class ceil  (in bytes per second)

This allows us to setup HTB on 40Gbps links, as 32bit limit is
actually ~34Gbps
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/pkt_sched.h

@@ -357,6 +357,8 @@ enum {
 	TCA_HTB_CTAB,
 	TCA_HTB_RTAB,
 	TCA_HTB_DIRECT_QLEN,
+	TCA_HTB_RATE64,
+	TCA_HTB_CEIL64,
 	__TCA_HTB_MAX,
 };
 

net/sched/sch_htb.c

@@ -997,6 +997,8 @@ static const struct nla_policy htb_policy[TCA_HTB_MAX + 1] = {
 	[TCA_HTB_CTAB]	= { .type = NLA_BINARY, .len = TC_RTAB_SIZE },
 	[TCA_HTB_RTAB]	= { .type = NLA_BINARY, .len = TC_RTAB_SIZE },
 	[TCA_HTB_DIRECT_QLEN] = { .type = NLA_U32 },
+	[TCA_HTB_RATE64] = { .type = NLA_U64 },
+	[TCA_HTB_CEIL64] = { .type = NLA_U64 },
 };
 
 static void htb_work_func(struct work_struct *work)
@@ -1114,6 +1116,12 @@ static int htb_dump_class(struct Qdisc *sch, unsigned long arg,
 	opt.level = cl->level;
 	if (nla_put(skb, TCA_HTB_PARMS, sizeof(opt), &opt))
 		goto nla_put_failure;
+	if ((cl->rate.rate_bytes_ps >= (1ULL << 32)) &&
+	    nla_put_u64(skb, TCA_HTB_RATE64, cl->rate.rate_bytes_ps))
+		goto nla_put_failure;
+	if ((cl->ceil.rate_bytes_ps >= (1ULL << 32)) &&
+	    nla_put_u64(skb, TCA_HTB_CEIL64, cl->ceil.rate_bytes_ps))
+		goto nla_put_failure;
 
 	nla_nest_end(skb, nest);
 	spin_unlock_bh(root_lock);
@@ -1332,6 +1340,7 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
 	struct qdisc_rate_table *rtab = NULL, *ctab = NULL;
 	struct nlattr *tb[TCA_HTB_MAX + 1];
 	struct tc_htb_opt *hopt;
+	u64 rate64, ceil64;
 
 	/* extract all subattrs from opt attr */
 	if (!opt)
@@ -1491,8 +1500,12 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
 			cl->prio = TC_HTB_NUMPRIO - 1;
 	}
 
-	psched_ratecfg_precompute(&cl->rate, &hopt->rate, 0);
-	psched_ratecfg_precompute(&cl->ceil, &hopt->ceil, 0);
+	rate64 = tb[TCA_HTB_RATE64] ? nla_get_u64(tb[TCA_HTB_RATE64]) : 0;
+
+	ceil64 = tb[TCA_HTB_CEIL64] ? nla_get_u64(tb[TCA_HTB_CEIL64]) : 0;
+
+	psched_ratecfg_precompute(&cl->rate, &hopt->rate, rate64);
+	psched_ratecfg_precompute(&cl->ceil, &hopt->ceil, ceil64);
 
 	cl->buffer = PSCHED_TICKS2NS(hopt->buffer);
 	cl->cbuffer = PSCHED_TICKS2NS(hopt->cbuffer);