libxl: Make libxl_retrieve_domain_configuration async

.. because it makes QMP calls which are going to be async.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>

tools/libxl/libxl.h

@@ -1221,6 +1221,7 @@ void libxl_mac_copy(libxl_ctx *ctx, libxl_mac *dst, const libxl_mac *src);
  *   libxl_domain_unpause()
  *   libxl_send_trigger()
  *   libxl_set_vcpuonline()
+ *   libxl_retrieve_domain_configuration()
  */
 #define LIBXL_HAVE_FN_USING_QMP_ASYNC 1
 
@@ -1564,8 +1565,18 @@ void libxl_domain_config_dispose(libxl_domain_config *d_config);
  * works with DomU.
  */
 int libxl_retrieve_domain_configuration(libxl_ctx *ctx, uint32_t domid,
-                                        libxl_domain_config *d_config)
+                                        libxl_domain_config *d_config,
+                                        const libxl_asyncop_how *ao_how)
                                         LIBXL_EXTERNAL_CALLERS_ONLY;
+#if defined(LIBXL_API_VERSION) && LIBXL_API_VERSION < 0x041300
+static inline int libxl_retrieve_domain_configuration_0x041200(
+    libxl_ctx *ctx, uint32_t domid, libxl_domain_config *d_config)
+{
+    return libxl_retrieve_domain_configuration(ctx, domid, d_config, NULL);
+}
+#define libxl_retrieve_domain_configuration \
+    libxl_retrieve_domain_configuration_0x041200
+#endif
 
 int libxl_domain_suspend(libxl_ctx *ctx, uint32_t domid, int fd,
                          int flags, /* LIBXL_SUSPEND_* */

tools/libxl/libxl_domain.c

@@ -1594,14 +1594,13 @@ out:
 }
 
 int libxl_retrieve_domain_configuration(libxl_ctx *ctx, uint32_t domid,
-                                        libxl_domain_config *d_config)
+                                        libxl_domain_config *d_config,
+                                        const libxl_asyncop_how *ao_how)
 {
-    GC_INIT(ctx);
+    AO_CREATE(ctx, domid, ao_how);
     int rc;
     libxl__domain_userdata_lock *lock = NULL;
 
-    CTX_LOCK;
-
     lock = libxl__lock_domain_userdata(gc, domid);
     if (!lock) {
         rc = ERROR_LOCK_FAIL;
@@ -1808,9 +1807,10 @@ int libxl_retrieve_domain_configuration(libxl_ctx *ctx, uint32_t domid,
 
 out:
     if (lock) libxl__unlock_domain_userdata(lock);
-    CTX_UNLOCK;
-    GC_FREE;
-    return rc;
+    if (rc)
+        return AO_CREATE_FAIL(rc);
+    libxl__ao_complete(egc, ao, rc);
+    return AO_INPROGRESS;
 }
 
 /*

tools/xl/xl_info.c

@@ -464,7 +464,8 @@ static void list_domains_details(const libxl_dominfo *info, int nb_domain)
 
     for (i = 0; i < nb_domain; i++) {
         libxl_domain_config_init(&d_config);
-        rc = libxl_retrieve_domain_configuration(ctx, info[i].domid, &d_config);
+        rc = libxl_retrieve_domain_configuration(ctx, info[i].domid,
+                                                 &d_config, NULL);
         if (rc)
             continue;
         if (default_output_format == OUTPUT_FORMAT_JSON)

tools/xl/xl_saverestore.c

@@ -56,7 +56,8 @@ void save_domain_core_begin(uint32_t domid,
                           &d_config);
         free(config_v);
     } else {
-        rc = libxl_retrieve_domain_configuration(ctx, domid, &d_config);
+        rc = libxl_retrieve_domain_configuration(ctx, domid, &d_config,
+                                                 NULL);
         if (rc) {
             fprintf(stderr, "unable to retrieve domain configuration\n");
             exit(EXIT_FAILURE);

tools/xl/xl_vmcontrol.c

@@ -377,7 +377,8 @@ static void reload_domain_config(uint32_t domid,
     }
 
     libxl_domain_config_init(&d_config_new);
-    rc = libxl_retrieve_domain_configuration(ctx, domid, &d_config_new);
+    rc = libxl_retrieve_domain_configuration(ctx, domid, &d_config_new,
+                                             NULL);
     if (rc) {
         LOG("failed to retrieve guest configuration (rc=%d). "
             "reusing old configuration", rc);