spice: turn client_migrate_info to async

RHBZ 737921
Spice client is required to connect to the migration target before/as migration
starts. Since after migration starts, the target qemu is blocked and cannot accept new spice client
we trigger the connection to the target upon client_migrate_info command.
client_migrate_info completion cb will be called after spice client has been
connected to the target (or a timeout). See following patches and spice patches.
Signed-off-by: NYonit Halperin <yhalperi@redhat.com>
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

hmp-commands.hx

@@ -824,7 +824,8 @@ ETEXI
         .params     = "protocol hostname port tls-port cert-subject",
         .help       = "send migration info to spice/vnc client",
         .user_print = monitor_user_noop,
-        .mhandler.cmd_new = client_migrate_info,
+        .mhandler.cmd_async = client_migrate_info,
+        .flags      = MONITOR_CMD_ASYNC,
     },
 
 STEXI

monitor.c

@@ -1153,7 +1153,8 @@ static int add_graphics_client(Monitor *mon, const QDict *qdict, QObject **ret_d
     return -1;
 }
 
-static int client_migrate_info(Monitor *mon, const QDict *qdict, QObject **ret_data)
+static int client_migrate_info(Monitor *mon, const QDict *qdict,
+                               MonitorCompletion cb, void *opaque)
 {
     const char *protocol = qdict_get_str(qdict, "protocol");
     const char *hostname = qdict_get_str(qdict, "hostname");
@@ -1168,7 +1169,8 @@ static int client_migrate_info(Monitor *mon, const QDict *qdict, QObject **ret_d
             return -1;
         }
 
-        ret = qemu_spice_migrate_info(hostname, port, tls_port, subject);
+        ret = qemu_spice_migrate_info(hostname, port, tls_port, subject,
+                                      cb, opaque);
         if (ret != 0) {
             qerror_report(QERR_UNDEFINED_ERROR);
             return -1;

qmp-commands.hx

@@ -569,7 +569,8 @@ EQMP
         .params     = "protocol hostname port tls-port cert-subject",
         .help       = "send migration info to spice/vnc client",
         .user_print = monitor_user_noop,
-        .mhandler.cmd_new = client_migrate_info,
+        .mhandler.cmd_async = client_migrate_info,
+        .flags      = MONITOR_CMD_ASYNC,
     },
 
 SQMP

ui/qemu-spice.h

@@ -25,6 +25,7 @@
 #include "qemu-option.h"
 #include "qemu-config.h"
 #include "qemu-char.h"
+#include "monitor.h"
 
 extern int using_spice;
 
@@ -37,7 +38,8 @@ int qemu_spice_set_passwd(const char *passwd,
                           bool fail_if_connected, bool disconnect_if_connected);
 int qemu_spice_set_pw_expire(time_t expires);
 int qemu_spice_migrate_info(const char *hostname, int port, int tls_port,
-                            const char *subject);
+                            const char *subject,
+                            MonitorCompletion cb, void *opaque);
 
 void do_info_spice_print(Monitor *mon, const QObject *data);
 void do_info_spice(Monitor *mon, QObject **ret_data);
@@ -45,6 +47,7 @@ void do_info_spice(Monitor *mon, QObject **ret_data);
 int qemu_chr_open_spice(QemuOpts *opts, CharDriverState **_chr);
 
 #else  /* CONFIG_SPICE */
+#include "monitor.h"
 
 #define using_spice 0
 static inline int qemu_spice_set_passwd(const char *passwd,
@@ -57,8 +60,13 @@ static inline int qemu_spice_set_pw_expire(time_t expires)
 {
     return -1;
 }
-static inline int qemu_spice_migrate_info(const char *h, int p, int t, const char *s)
-{ return -1; }
+static inline int qemu_spice_migrate_info(const char *h, int p, int t,
+                                          const char *s,
+                                          MonitorCompletion cb, void *opaque)
+{
+    cb(opaque, NULL);
+    return -1;
+}
 
 #endif /* CONFIG_SPICE */
 

ui/spice-core.c

@@ -457,10 +457,14 @@ static void migration_state_notifier(Notifier *notifier, void *data)
 }
 
 int qemu_spice_migrate_info(const char *hostname, int port, int tls_port,
-                            const char *subject)
+                            const char *subject,
+                            MonitorCompletion *cb, void *opaque)
 {
-    return spice_server_migrate_info(spice_server, hostname,
-                                     port, tls_port, subject);
+    int ret;
+    ret = spice_server_migrate_info(spice_server, hostname,
+                                    port, tls_port, subject);
+    cb(opaque, NULL);
+    return ret;
 }
 
 static int add_channel(const char *name, const char *value, void *opaque)