kvm tools: carefully send and handle stop ipc

Remove struct stop_cmd and use kvm_ipc__send().

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

builtin-run.c

@@ -567,6 +567,9 @@ static void handle_sigalrm(int sig)
 
 static void handle_stop(int fd, u32 type, u32 len, u8 *msg)
 {
+	if (WARN_ON(type != KVM_IPC_STOP || len))
+		return;
+
 	kvm_cpu__reboot();
 }
 

builtin-stop.c

@@ -9,11 +9,6 @@
 #include <string.h>
 #include <signal.h>
 
-struct stop_cmd {
-	u32 type;
-	u32 len;
-};
-
 static bool all;
 static const char *instance_name;
 
@@ -46,14 +41,7 @@ void kvm_stop_help(void)
 
 static int do_stop(const char *name, int sock)
 {
-	struct stop_cmd cmd = {KVM_IPC_STOP, 0};
-	int r;
-
-	r = write(sock, &cmd, sizeof(cmd));
-	if (r < 0)
-		return r;
-
-	return 0;
+	return kvm_ipc__send(sock, KVM_IPC_STOP);
 }
 
 int kvm_cmd_stop(int argc, const char **argv, const char *prefix)