sock: Handle rcvlowat and priority options

And write a test for them.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

protobuf/sk-opts.proto

@@ -7,4 +7,7 @@ message sk_opts_entry {
 	required uint64		so_rcv_tmo_sec	= 5;
 	required uint64		so_rcv_tmo_usec	= 6;
 	optional bool		reuseaddr	= 7;
+
+	optional uint32		so_priority	= 8;
+	optional uint32		so_rcvlowat	= 9;
 }

sockets.c

@@ -78,6 +78,14 @@ int restore_socket_opts(int sk, SkOptsEntry *soe)
 	pr_info("%d restore sndbuf %d rcv buf %d\n", sk, soe->so_sndbuf, soe->so_rcvbuf);
 	ret |= restore_opt(sk, SOL_SOCKET, SO_SNDBUFFORCE, &soe->so_sndbuf);
 	ret |= restore_opt(sk, SOL_SOCKET, SO_RCVBUFFORCE, &soe->so_rcvbuf);
+	if (soe->has_so_priority) {
+		pr_debug("\trestore priority %d for socket\n", soe->so_priority);
+		ret |= restore_opt(sk, SOL_SOCKET, SO_PRIORITY, &soe->so_priority);
+	}
+	if (soe->has_so_rcvlowat) {
+		pr_debug("\trestore rcvlowat %d for socket\n", soe->so_rcvlowat);
+		ret |= restore_opt(sk, SOL_SOCKET, SO_RCVLOWAT, &soe->so_rcvlowat);
+	}
 
 	tv.tv_sec = soe->so_snd_tmo_sec;
 	tv.tv_usec = soe->so_snd_tmo_usec;
@@ -117,6 +125,10 @@ int dump_socket_opts(int sk, SkOptsEntry *soe)
 
 	ret |= dump_opt(sk, SOL_SOCKET, SO_SNDBUF, &soe->so_sndbuf);
 	ret |= dump_opt(sk, SOL_SOCKET, SO_RCVBUF, &soe->so_rcvbuf);
+	soe->has_so_priority = true;
+	ret |= dump_opt(sk, SOL_SOCKET, SO_PRIORITY, &soe->so_priority);
+	soe->has_so_rcvlowat = true;
+	ret |= dump_opt(sk, SOL_SOCKET, SO_RCVLOWAT, &soe->so_rcvlowat);
 
 	ret |= dump_opt(sk, SOL_SOCKET, SO_SNDTIMEO, &tv);
 	soe->so_snd_tmo_sec = tv.tv_sec;
@@ -352,6 +364,8 @@ void show_socket_opts(SkOptsEntry *soe)
 	pr_msg("rcvbuf: %u  ", soe->so_rcvbuf);
 	pr_msg("sndtmo: %lu.%lu  ", soe->so_snd_tmo_sec, soe->so_snd_tmo_usec);
 	pr_msg("rcvtmo: %lu.%lu  ", soe->so_rcv_tmo_sec, soe->so_rcv_tmo_usec);
+	pr_msg("prio:   %u  ", soe->so_priority);
+	pr_msg("rlowat: %u  ", soe->so_rcvlowat);
 
 	pr_msg("\n");
 }

test/zdtm.sh

@@ -30,6 +30,7 @@ streaming/pipe_loop00
 streaming/pipe_shared00
 transition/file_read
 static/sockets00
+static/sock_opts00
 static/sockets_spair
 static/sockets_dgram
 static/socket_queues

test/zdtm/live/static/Makefile

@@ -42,6 +42,7 @@ TST_NOFILE	=				\
 		socket_queues			\
 		socket_queues02			\
 		socket-tcp			\
+		sock_opts00			\
 		ipc_namespace			\
 		selfexe00			\
 		sem				\

test/zdtm/live/static/sock_opts00.c

+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+#include "zdtmtst.h"
+
+const char *test_doc	= "Check various socket options to work";
+const char *test_author	= "Pavel Emelyanov <xemul@parallels.com>";
+
+#define TEST_PORT 59687
+#define TEST_ADDR INADDR_ANY
+
+#define NOPTS	2
+
+int main(int argc, char ** argv)
+{
+	int sock, ret = 0, vname[NOPTS], val[NOPTS], rval, i;
+	socklen_t len = sizeof(int);
+
+	vname[0] = SO_PRIORITY;
+	vname[1] = SO_RCVLOWAT;
+
+	test_init(argc, argv);
+
+	sock = socket(PF_INET, SOCK_STREAM, 0);
+	if (sock < 0) {
+		err("can't create socket: %m");
+		return 1;
+	}
+
+	for (i = 0; i < NOPTS; i++) {
+		ret = getsockopt(sock, SOL_SOCKET, vname[i], &val[i], &len);
+		if (ret) {
+			err("can't get option %d", i);
+			return 1;
+		}
+
+		val[i]++;
+
+		ret = setsockopt(sock, SOL_SOCKET, vname[i], &val[i], len);
+		if (ret) {
+			err("can't set option %d", i);
+			return 1;
+		}
+
+		ret = getsockopt(sock, SOL_SOCKET, vname[i], &rval, &len);
+		if (ret) {
+			err("can't get option %d 2", i);
+			return 1;
+		}
+
+		if (rval != val[i]) {
+			if (rval + 1 == val[i]) {
+				err("can't reset option %d want %d have %d", i,
+						val[i], rval);
+				return 1;
+			}
+
+			/* kernel tuned things up on set */
+			val[i] = rval;
+		}
+	}
+
+	test_daemon();
+	test_waitsig();
+
+	for (i = 0; i < NOPTS; i++) {
+		ret = getsockopt(sock, SOL_SOCKET, vname[i], &rval, &len);
+		if (ret) {
+			err("can't get option %d again", i);
+			return 1;
+		}
+
+		if (val[i] != rval) {
+			fail("option %d changed", i);
+			return 1;
+		}
+	}
+
+	pass();
+	close(sock);
+
+	return 0;
+}