police, implement overhead parameter parsing.

For police, implement overhead parameter parsing.

The change is ABI (Application Binary Interface) backward compatible
with older kernels, but will first have effect from kernel 2.6.24.
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com>

tc/m_police.c

@@ -35,7 +35,7 @@ struct action_util police_action_util = {
 static void usage(void)
 {
 	fprintf(stderr, "Usage: ... police rate BPS burst BYTES[/BYTES] [ mtu BYTES[/BYTES] ]\n");
-	fprintf(stderr, "                [ peakrate BPS ] [ avrate BPS ]\n");
+	fprintf(stderr, "                [ peakrate BPS ] [ avrate BPS ] [ overhead BYTES ]\n");
 	fprintf(stderr, "                [ ACTIONTERM ]\n");
 	fprintf(stderr, "Old Syntax ACTIONTERM := action <EXCEEDACT>[/NOTEXCEEDACT] \n");
 	fprintf(stderr, "New Syntax ACTIONTERM := conform-exceed <EXCEEDACT>[/NOTEXCEEDACT] \n");
@@ -133,6 +133,7 @@ int act_parse_police(struct action_util *a,int *argc_p, char ***argv_p, int tca_
 	__u32 avrate = 0;
 	int presult = 0;
 	unsigned buffer=0, mtu=0, mpu=0;
+	unsigned short overhead;
 	int Rcell_log=-1, Pcell_log = -1;
 	struct rtattr *tail;
 
@@ -234,6 +235,11 @@ int act_parse_police(struct action_util *a,int *argc_p, char ***argv_p, int tca_
 				fprintf(stderr, "Illegal \"action\"\n");
 				return -1;
 			}
+		} else if (matches(*argv, "overhead") == 0) {
+			NEXT_ARG();
+			if (get_u16(&overhead, *argv, 10)) {
+				explain1("overhead"); return -1;
+			}
 		} else if (strcmp(*argv, "help") == 0) {
 			usage();
 		} else {
@@ -263,6 +269,7 @@ int act_parse_police(struct action_util *a,int *argc_p, char ***argv_p, int tca_
 
 	if (p.rate.rate) {
 		p.rate.mpu = mpu;
+		p.rate.overhead = overhead;
 		if (tc_calc_rtable(&p.rate, rtab, Rcell_log, mtu) < 0) {
 			fprintf(stderr, "TBF: failed to calculate rate table.\n");
 			return -1;
@@ -272,6 +279,7 @@ int act_parse_police(struct action_util *a,int *argc_p, char ***argv_p, int tca_
 	p.mtu = mtu;
 	if (p.peakrate.rate) {
 		p.peakrate.mpu = mpu;
+		p.peakrate.overhead = overhead;
 		if (tc_calc_rtable(&p.peakrate, ptab, Pcell_log, mtu) < 0) {
 			fprintf(stderr, "POLICE: failed to calculate peak rate table.\n");
 			return -1;
@@ -344,6 +352,7 @@ print_police(struct action_util *a, FILE *f, struct rtattr *arg)
 		fprintf(f, "/%s ", police_action_n2a(*(int*)RTA_DATA(tb[TCA_POLICE_RESULT]), b1, sizeof(b1)));
 	} else
 		fprintf(f, " ");
+	fprintf(f, "overhead %ub ", p->rate.overhead);
 	fprintf(f, "\nref %d bind %d\n",p->refcnt, p->bindcnt);
 
 	return 0;