add quickack option to ip route

This patch adds quickack option to enable/disable TCP quick ack
mode for per-route.

Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Cong Wang <amwang@redhat.com>

include/linux/rtnetlink.h

@@ -386,6 +386,8 @@ enum {
 #define RTAX_RTO_MIN RTAX_RTO_MIN
 	RTAX_INITRWND,
 #define RTAX_INITRWND RTAX_INITRWND
+	RTAX_QUICKACK,
+#define RTAX_QUICKACK RTAX_QUICKACK
 	__RTAX_MAX
 };
 

ip/iproute.c

@@ -52,6 +52,7 @@ static const char *mx_names[RTAX_MAX+1] = {
 	[RTAX_FEATURES] = "features",
 	[RTAX_RTO_MIN]	= "rto_min",
 	[RTAX_INITRWND]	= "initrwnd",
+	[RTAX_QUICKACK]	= "quickack",
 };
 static void usage(void) __attribute__((noreturn));
 
@@ -79,6 +80,7 @@ static void usage(void)
 	fprintf(stderr, "           [ window NUMBER] [ cwnd NUMBER ] [ initcwnd NUMBER ]\n");
 	fprintf(stderr, "           [ ssthresh NUMBER ] [ realms REALM ] [ src ADDRESS ]\n");
 	fprintf(stderr, "           [ rto_min TIME ] [ hoplimit NUMBER ] [ initrwnd NUMBER ]\n");
+	fprintf(stderr, "           [ quickack BOOL ]\n");
 	fprintf(stderr, "TYPE := [ unicast | local | broadcast | multicast | throw |\n");
 	fprintf(stderr, "          unreachable | prohibit | blackhole | nat ]\n");
 	fprintf(stderr, "TABLE_ID := [ local | main | default | all | NUMBER ]\n");
@@ -86,6 +88,7 @@ static void usage(void)
 	fprintf(stderr, "NHFLAGS := [ onlink | pervasive ]\n");
 	fprintf(stderr, "RTPROTO := [ kernel | boot | static | NUMBER ]\n");
 	fprintf(stderr, "TIME := NUMBER[s|ms]\n");
+	fprintf(stderr, "BOOL := [1|0]\n");
 	exit(-1);
 }
 
@@ -885,6 +888,14 @@ static int iproute_modify(int cmd, unsigned flags, int argc, char **argv)
 			if (get_unsigned(&win, *argv, 0))
 				invarg("\"initrwnd\" value is invalid\n", *argv);
 			rta_addattr32(mxrta, sizeof(mxbuf), RTAX_INITRWND, win);
+		} else if (matches(*argv, "quickack") == 0) {
+			unsigned quickack;
+			NEXT_ARG();
+			if (get_unsigned(&quickack, *argv, 0))
+				invarg("\"quickack\" value is invalid\n", *argv);
+			if (quickack != 1 && quickack != 0)
+				invarg("\"quickack\" value should be 0 or 1\n", *argv);
+			rta_addattr32(mxrta, sizeof(mxbuf), RTAX_QUICKACK, quickack);
 		} else if (matches(*argv, "rttvar") == 0) {
 			unsigned win;
 			NEXT_ARG();

man/man8/ip-route.8.in

@@ -111,6 +111,8 @@ replace " } "
 .IR NUMBER " ] [ "
 .B  initrwnd
 .IR NUMBER " ]"
+.B  quickack
+.IR BOOL " ]"
 
 .ti -8
 .IR TYPE " := [ "
@@ -400,6 +402,10 @@ the initial receive window size for connections to this destination.
 Actual window size is this value multiplied by the MSS of the connection.
 The default value is zero, meaning to use Slow Start value.
 
+.TP
+.BI quickack " BOOL " "(3.11+ only)"
+Enable or disable quick ack for connections to this destination.
+
 .TP
 .BI advmss " NUMBER " "(2.3.15+ only)"
 the MSS ('Maximal Segment Size') to advertise to these