lazy-pages: enable lazy-pages via RPC

To use lazy-pages from runc '--lazy-pages' functionality needs to be
accessible via RPC. This enables lazy-pages via RPC.

The information on which port to listen is taken from the
criu_page_server_info protobuf structure. If the user has enabled
lazy-pages via RPC only criu_page_server_info.port is evaluated
to get the listen port.

With additional patches in runc is it possible to use lazy-restore
with 'runc checkpoint' and 'runc restore'.

travis-ci: success for lazy-pages: enable lazy-pages via RPC
Signed-off-by: Adrian Reber <areber@redhat.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/cr-service.c

@@ -371,10 +371,16 @@ static int setup_opts_from_req(int sk, CriuOpts *req)
 		opts.exec_cmd[req->n_exec_cmd] = NULL;
 	}
 
+	if (req->has_lazy_pages) {
+		opts.lazy_pages = req->lazy_pages;
+	}
+
 	if (req->ps) {
+		opts.port = htons((short)req->ps->port);
+
+		if (!opts.lazy_pages) {
 			opts.use_page_server = true;
 			opts.addr = req->ps->address;
-		opts.port = htons((short)req->ps->port);
 
 			if (req->ps->has_fd) {
 				if (!opts.swrk_restore)
@@ -383,6 +389,7 @@ static int setup_opts_from_req(int sk, CriuOpts *req)
 				opts.ps_socket = req->ps->fd;
 			}
 		}
+	}
 
 	if (req->notify_scripts && add_rpc_notify(sk))
 		goto err;

images/rpc.proto

@@ -108,6 +108,7 @@ message criu_opts {
 	optional uint32			timeout			= 45;
 	optional bool			tcp_skip_in_flight	= 46;
 	optional bool			weak_sysctls		= 47;
+	optional bool			lazy_pages		= 48;
 	optional int32			status_fd		= 49;
 	optional bool			orphan_pts_master	= 50;
 }