tests/qtest/migration: Move qmp helpers to a separate file

We current have a bunch of non-test functions in migration-test.c and
some others in migration-helpers.c. In order to split migration-test.c
into separate test binaries, these helpers need to go somewhere
else.

To avoid making migration-helpers even larger, move all QMP-related
functions into a new migration-qmp.c file and put it under the
qtest/migration/ directory.

The new file holds everything that has as its main responsibility to
call into QMP.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>

tests/qtest/meson.build

@@ -335,6 +335,7 @@ tpmemu_files = ['tpm-emu.c', 'tpm-util.c', 'tpm-tests.c']
 migration_files = [files(
   'migration-helpers.c',
   'migration/bootfile.c',
+  'migration/migration-qmp.c',
 )]
 
 if gnutls.found()
@@ -348,7 +349,8 @@ endif
 qtests = {
   'bios-tables-test': [io, 'boot-sector.c', 'acpi-utils.c', 'tpm-emu.c'],
   'cdrom-test': files('boot-sector.c'),
-  'dbus-vmstate-test': files('migration-helpers.c') + dbus_vmstate1,
+  'dbus-vmstate-test': files('migration/migration-qmp.c',
+                             'migration-helpers.c') + dbus_vmstate1,
   'erst-test': files('erst-test.c'),
   'ivshmem-test': [rt, '../../contrib/ivshmem-server/ivshmem-server.c'],
   'migration-test': migration_files,

tests/qtest/migration-helpers.c

@@ -12,7 +12,6 @@
 
 #include "qemu/osdep.h"
 #include "qemu/ctype.h"
-#include "qapi/qmp/qjson.h"
 #include "qapi/qapi-visit-sockets.h"
 #include "qapi/qobject-input-visitor.h"
 #include "qapi/error.h"
@@ -23,14 +22,6 @@
 #include "migration-helpers.h"
 #include "migration/bootfile.h"
 
-/*
- * Number of seconds we wait when looking for migration
- * status changes, to avoid test suite hanging forever
- * when things go wrong. Needs to be higher enough to
- * avoid false positives on loaded hosts.
- */
-#define MIGRATION_STATUS_WAIT_TIMEOUT 120
-
 static char *SocketAddress_to_str(SocketAddress *addr)
 {
     switch (addr->type) {
@@ -100,8 +91,7 @@ static SocketAddressList *migrate_get_socket_address(QTestState *who)
     return addrs;
 }
 
-static char *
+char *migrate_get_connect_uri(QTestState *who)
-migrate_get_connect_uri(QTestState *who)
 {
     SocketAddressList *addrs;
     char *connect_uri;
@@ -126,7 +116,7 @@ migrate_get_connect_qdict(QTestState *who)
     return connect_qdict;
 }
 
-static void migrate_set_ports(QTestState *to, QList *channel_list)
+void migrate_set_ports(QTestState *to, QList *channel_list)
 {
     QDict *addr;
     QListEntry *entry;
@@ -168,222 +158,6 @@ bool migrate_watch_for_events(QTestState *who, const char *name,
     return false;
 }
 
-void migrate_qmp_fail(QTestState *who, const char *uri,
-                      const char *channels, const char *fmt, ...)
-{
-    va_list ap;
-    QDict *args, *err;
-
-    va_start(ap, fmt);
-    args = qdict_from_vjsonf_nofail(fmt, ap);
-    va_end(ap);
-
-    g_assert(!qdict_haskey(args, "uri"));
-    if (uri) {
-        qdict_put_str(args, "uri", uri);
-    }
-
-    g_assert(!qdict_haskey(args, "channels"));
-    if (channels) {
-        QObject *channels_obj = qobject_from_json(channels, &error_abort);
-        qdict_put_obj(args, "channels", channels_obj);
-    }
-
-    err = qtest_qmp_assert_failure_ref(
-        who, "{ 'execute': 'migrate', 'arguments': %p}", args);
-
-    g_assert(qdict_haskey(err, "desc"));
-
-    qobject_unref(err);
-}
-
-/*
- * Send QMP command "migrate".
- * Arguments are built from @fmt... (formatted like
- * qobject_from_jsonf_nofail()) with "uri": @uri spliced in.
- */
-void migrate_qmp(QTestState *who, QTestState *to, const char *uri,
-                 const char *channels, const char *fmt, ...)
-{
-    va_list ap;
-    QDict *args;
-    g_autofree char *connect_uri = NULL;
-
-    va_start(ap, fmt);
-    args = qdict_from_vjsonf_nofail(fmt, ap);
-    va_end(ap);
-
-    g_assert(!qdict_haskey(args, "uri"));
-    if (uri) {
-        qdict_put_str(args, "uri", uri);
-    } else if (!channels) {
-        connect_uri = migrate_get_connect_uri(to);
-        qdict_put_str(args, "uri", connect_uri);
-    }
-
-    g_assert(!qdict_haskey(args, "channels"));
-    if (channels) {
-        QObject *channels_obj = qobject_from_json(channels, &error_abort);
-        QList *channel_list = qobject_to(QList, channels_obj);
-        migrate_set_ports(to, channel_list);
-        qdict_put_obj(args, "channels", channels_obj);
-    }
-
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate', 'arguments': %p}", args);
-}
-
-void migrate_set_capability(QTestState *who, const char *capability,
-                            bool value)
-{
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate-set-capabilities',"
-                             "'arguments': { "
-                             "'capabilities': [ { "
-                             "'capability': %s, 'state': %i } ] } }",
-                             capability, value);
-}
-
-void migrate_incoming_qmp(QTestState *to, const char *uri, const char *fmt, ...)
-{
-    va_list ap;
-    QDict *args, *rsp;
-
-    va_start(ap, fmt);
-    args = qdict_from_vjsonf_nofail(fmt, ap);
-    va_end(ap);
-
-    g_assert(!qdict_haskey(args, "uri"));
-    qdict_put_str(args, "uri", uri);
-
-    /* This function relies on the event to work, make sure it's enabled */
-    migrate_set_capability(to, "events", true);
-
-    rsp = qtest_qmp(to, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                    args);
-
-    if (!qdict_haskey(rsp, "return")) {
-        g_autoptr(GString) s = qobject_to_json_pretty(QOBJECT(rsp), true);
-        g_test_message("%s", s->str);
-    }
-
-    g_assert(qdict_haskey(rsp, "return"));
-    qobject_unref(rsp);
-
-    migration_event_wait(to, "setup");
-}
-
-/*
- * Note: caller is responsible to free the returned object via
- * qobject_unref() after use
- */
-QDict *migrate_query(QTestState *who)
-{
-    return qtest_qmp_assert_success_ref(who, "{ 'execute': 'query-migrate' }");
-}
-
-QDict *migrate_query_not_failed(QTestState *who)
-{
-    const char *status;
-    QDict *rsp = migrate_query(who);
-    status = qdict_get_str(rsp, "status");
-    if (g_str_equal(status, "failed")) {
-        g_printerr("query-migrate shows failed migration: %s\n",
-                   qdict_get_str(rsp, "error-desc"));
-    }
-    g_assert(!g_str_equal(status, "failed"));
-    return rsp;
-}
-
-/*
- * Note: caller is responsible to free the returned object via
- * g_free() after use
- */
-static gchar *migrate_query_status(QTestState *who)
-{
-    QDict *rsp_return = migrate_query(who);
-    gchar *status = g_strdup(qdict_get_str(rsp_return, "status"));
-
-    g_assert(status);
-    qobject_unref(rsp_return);
-
-    return status;
-}
-
-static bool check_migration_status(QTestState *who, const char *goal,
-                                   const char **ungoals)
-{
-    bool ready;
-    char *current_status;
-    const char **ungoal;
-
-    current_status = migrate_query_status(who);
-    ready = strcmp(current_status, goal) == 0;
-    if (!ungoals) {
-        g_assert_cmpstr(current_status, !=, "failed");
-        /*
-         * If looking for a state other than completed,
-         * completion of migration would cause the test to
-         * hang.
-         */
-        if (strcmp(goal, "completed") != 0) {
-            g_assert_cmpstr(current_status, !=, "completed");
-        }
-    } else {
-        for (ungoal = ungoals; *ungoal; ungoal++) {
-            g_assert_cmpstr(current_status, !=,  *ungoal);
-        }
-    }
-    g_free(current_status);
-    return ready;
-}
-
-void wait_for_migration_status(QTestState *who,
-                               const char *goal, const char **ungoals)
-{
-    g_test_timer_start();
-    while (!check_migration_status(who, goal, ungoals)) {
-        usleep(1000);
-
-        g_assert(g_test_timer_elapsed() < MIGRATION_STATUS_WAIT_TIMEOUT);
-    }
-}
-
-void wait_for_migration_complete(QTestState *who)
-{
-    wait_for_migration_status(who, "completed", NULL);
-}
-
-void wait_for_migration_fail(QTestState *from, bool allow_active)
-{
-    g_test_timer_start();
-    QDict *rsp_return;
-    char *status;
-    bool failed;
-
-    do {
-        status = migrate_query_status(from);
-        bool result = !strcmp(status, "setup") || !strcmp(status, "failed") ||
-            (allow_active && !strcmp(status, "active"));
-        if (!result) {
-            fprintf(stderr, "%s: unexpected status status=%s allow_active=%d\n",
-                    __func__, status, allow_active);
-        }
-        g_assert(result);
-        failed = !strcmp(status, "failed");
-        g_free(status);
-
-        g_assert(g_test_timer_elapsed() < MIGRATION_STATUS_WAIT_TIMEOUT);
-    } while (!failed);
-
-    /* Is the machine currently running? */
-    rsp_return = qtest_qmp_assert_success_ref(from,
-                                              "{ 'execute': 'query-status' }");
-    g_assert(qdict_haskey(rsp_return, "running"));
-    g_assert(qdict_get_bool(rsp_return, "running"));
-    qobject_unref(rsp_return);
-}
-
 char *find_common_machine_version(const char *mtype, const char *var1,
                                   const char *var2)
 {
@@ -509,23 +283,3 @@ bool probe_o_direct_support(const char *tmpfs)
     return true;
 }
 #endif
-
-/*
- * Wait for a "MIGRATION" event.  This is what Libvirt uses to track
- * migration status changes.
- */
-void migration_event_wait(QTestState *s, const char *target)
-{
-    QDict *response, *data;
-    const char *status;
-    bool found;
-
-    do {
-        response = qtest_qmp_eventwait_ref(s, "MIGRATION");
-        data = qdict_get_qdict(response, "data");
-        g_assert(data);
-        status = qdict_get_str(data, "status");
-        found = (strcmp(status, target) == 0);
-        qobject_unref(response);
-    } while (!found);
-}

tests/qtest/migration-helpers.h

@@ -25,21 +25,6 @@ typedef struct QTestMigrationState {
 bool migrate_watch_for_events(QTestState *who, const char *name,
                               QDict *event, void *opaque);
 
-G_GNUC_PRINTF(5, 6)
-void migrate_qmp(QTestState *who, QTestState *to, const char *uri,
-                 const char *channels, const char *fmt, ...);
-
-G_GNUC_PRINTF(3, 4)
-void migrate_incoming_qmp(QTestState *who, const char *uri,
-                          const char *fmt, ...);
-
-G_GNUC_PRINTF(4, 5)
-void migrate_qmp_fail(QTestState *who, const char *uri,
-                      const char *channels, const char *fmt, ...);
-
-void migrate_set_capability(QTestState *who, const char *capability,
-                            bool value);
-
 QDict *migrate_query(QTestState *who);
 QDict *migrate_query_not_failed(QTestState *who);
 
@@ -63,6 +48,7 @@ static inline bool probe_o_direct_support(const char *tmpfs)
 }
 #endif
 void migration_test_add(const char *path, void (*fn)(void));
-void migration_event_wait(QTestState *s, const char *target);
+char *migrate_get_connect_uri(QTestState *who);
+void migrate_set_ports(QTestState *to, QList *channel_list);
 
 #endif /* MIGRATION_HELPERS_H */

tests/qtest/migration-test.c

@@ -13,18 +13,18 @@
 #include "qemu/osdep.h"
 
 #include "libqtest.h"
-#include "qapi/qmp/qdict.h"
+#include "qapi/qmp/qlist.h"
 #include "qemu/module.h"
 #include "qemu/option.h"
 #include "qemu/range.h"
 #include "qemu/sockets.h"
 #include "chardev/char.h"
 #include "crypto/tlscredspsk.h"
-#include "qapi/qmp/qlist.h"
 #include "ppc-util.h"
 
 #include "migration-helpers.h"
 #include "migration/bootfile.h"
+#include "migration/migration-qmp.h"
 #ifdef CONFIG_GNUTLS
 # include "tests/unit/crypto-tls-psk-helpers.h"
 # ifdef CONFIG_TASN1
@@ -170,89 +170,6 @@ static void wait_for_serial(const char *side)
     } while (true);
 }
 
-static void wait_for_stop(QTestState *who, QTestMigrationState *state)
-{
-    if (!state->stop_seen) {
-        qtest_qmp_eventwait(who, "STOP");
-    }
-}
-
-static void wait_for_resume(QTestState *who, QTestMigrationState *state)
-{
-    if (!state->resume_seen) {
-        qtest_qmp_eventwait(who, "RESUME");
-    }
-}
-
-static void wait_for_suspend(QTestState *who, QTestMigrationState *state)
-{
-    if (state->suspend_me && !state->suspend_seen) {
-        qtest_qmp_eventwait(who, "SUSPEND");
-    }
-}
-
-/*
- * It's tricky to use qemu's migration event capability with qtest,
- * events suddenly appearing confuse the qmp()/hmp() responses.
- */
-
-static int64_t read_ram_property_int(QTestState *who, const char *property)
-{
-    QDict *rsp_return, *rsp_ram;
-    int64_t result;
-
-    rsp_return = migrate_query_not_failed(who);
-    if (!qdict_haskey(rsp_return, "ram")) {
-        /* Still in setup */
-        result = 0;
-    } else {
-        rsp_ram = qdict_get_qdict(rsp_return, "ram");
-        result = qdict_get_try_int(rsp_ram, property, 0);
-    }
-    qobject_unref(rsp_return);
-    return result;
-}
-
-static int64_t read_migrate_property_int(QTestState *who, const char *property)
-{
-    QDict *rsp_return;
-    int64_t result;
-
-    rsp_return = migrate_query_not_failed(who);
-    result = qdict_get_try_int(rsp_return, property, 0);
-    qobject_unref(rsp_return);
-    return result;
-}
-
-static uint64_t get_migration_pass(QTestState *who)
-{
-    return read_ram_property_int(who, "dirty-sync-count");
-}
-
-static void read_blocktime(QTestState *who)
-{
-    QDict *rsp_return;
-
-    rsp_return = migrate_query_not_failed(who);
-    g_assert(qdict_haskey(rsp_return, "postcopy-blocktime"));
-    qobject_unref(rsp_return);
-}
-
-/*
- * Wait for two changes in the migration pass count, but bail if we stop.
- */
-static void wait_for_migration_pass(QTestState *who)
-{
-    uint64_t pass, prev_pass = 0, changes = 0;
-
-    while (changes < 2 && !src_state.stop_seen && !src_state.suspend_seen) {
-        usleep(1000);
-        pass = get_migration_pass(who);
-        changes += (pass != prev_pass);
-        prev_pass = pass;
-    }
-}
-
 static void check_guests_ram(QTestState *who)
 {
     /* Our ASM test will have been incrementing one byte from each page from
@@ -308,114 +225,6 @@ static void cleanup(const char *filename)
     unlink(path);
 }
 
-static long long migrate_get_parameter_int(QTestState *who,
-                                           const char *parameter)
-{
-    QDict *rsp;
-    long long result;
-
-    rsp = qtest_qmp_assert_success_ref(
-        who, "{ 'execute': 'query-migrate-parameters' }");
-    result = qdict_get_int(rsp, parameter);
-    qobject_unref(rsp);
-    return result;
-}
-
-static void migrate_check_parameter_int(QTestState *who, const char *parameter,
-                                        long long value)
-{
-    long long result;
-
-    result = migrate_get_parameter_int(who, parameter);
-    g_assert_cmpint(result, ==, value);
-}
-
-static void migrate_set_parameter_int(QTestState *who, const char *parameter,
-                                      long long value)
-{
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate-set-parameters',"
-                             "'arguments': { %s: %lld } }",
-                             parameter, value);
-    migrate_check_parameter_int(who, parameter, value);
-}
-
-static char *migrate_get_parameter_str(QTestState *who,
-                                       const char *parameter)
-{
-    QDict *rsp;
-    char *result;
-
-    rsp = qtest_qmp_assert_success_ref(
-        who, "{ 'execute': 'query-migrate-parameters' }");
-    result = g_strdup(qdict_get_str(rsp, parameter));
-    qobject_unref(rsp);
-    return result;
-}
-
-static void migrate_check_parameter_str(QTestState *who, const char *parameter,
-                                        const char *value)
-{
-    g_autofree char *result = migrate_get_parameter_str(who, parameter);
-    g_assert_cmpstr(result, ==, value);
-}
-
-static void migrate_set_parameter_str(QTestState *who, const char *parameter,
-                                      const char *value)
-{
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate-set-parameters',"
-                             "'arguments': { %s: %s } }",
-                             parameter, value);
-    migrate_check_parameter_str(who, parameter, value);
-}
-
-static long long migrate_get_parameter_bool(QTestState *who,
-                                            const char *parameter)
-{
-    QDict *rsp;
-    int result;
-
-    rsp = qtest_qmp_assert_success_ref(
-        who, "{ 'execute': 'query-migrate-parameters' }");
-    result = qdict_get_bool(rsp, parameter);
-    qobject_unref(rsp);
-    return !!result;
-}
-
-static void migrate_check_parameter_bool(QTestState *who, const char *parameter,
-                                         int value)
-{
-    int result;
-
-    result = migrate_get_parameter_bool(who, parameter);
-    g_assert_cmpint(result, ==, value);
-}
-
-static void migrate_set_parameter_bool(QTestState *who, const char *parameter,
-                                       int value)
-{
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate-set-parameters',"
-                             "'arguments': { %s: %i } }",
-                             parameter, value);
-    migrate_check_parameter_bool(who, parameter, value);
-}
-
-static void migrate_ensure_non_converge(QTestState *who)
-{
-    /* Can't converge with 1ms downtime + 3 mbs bandwidth limit */
-    migrate_set_parameter_int(who, "max-bandwidth", 3 * 1000 * 1000);
-    migrate_set_parameter_int(who, "downtime-limit", 1);
-}
-
-static void migrate_ensure_converge(QTestState *who)
-{
-    /* Should converge with 30s downtime + 1 gbs bandwidth limit */
-    migrate_set_parameter_int(who, "max-bandwidth", 1 * 1000 * 1000 * 1000);
-    migrate_set_parameter_int(who, "downtime-limit", 30 * 1000);
-}
-
 /*
  * Our goal is to ensure that we run a single full migration
  * iteration, and also dirty memory, ensuring that at least
@@ -506,42 +315,6 @@ static void migrate_wait_for_dirty_mem(QTestState *from,
     } while (qtest_readb(from, watch_address) == watch_byte);
 }
 
-
-static void migrate_pause(QTestState *who)
-{
-    qtest_qmp_assert_success(who, "{ 'execute': 'migrate-pause' }");
-}
-
-static void migrate_continue(QTestState *who, const char *state)
-{
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate-continue',"
-                             "  'arguments': { 'state': %s } }",
-                             state);
-}
-
-static void migrate_recover(QTestState *who, const char *uri)
-{
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate-recover', "
-                             "  'id': 'recover-cmd', "
-                             "  'arguments': { 'uri': %s } }",
-                             uri);
-}
-
-static void migrate_cancel(QTestState *who)
-{
-    qtest_qmp_assert_success(who, "{ 'execute': 'migrate_cancel' }");
-}
-
-static void migrate_postcopy_start(QTestState *from, QTestState *to)
-{
-    qtest_qmp_assert_success(from, "{ 'execute': 'migrate-start-postcopy' }");
-
-    wait_for_stop(from, &src_state);
-    qtest_qmp_eventwait(to, "RESUME");
-}
-
 typedef struct {
     /*
      * QTEST_LOG=1 may override this.  When QTEST_LOG=1, we always dump errors
@@ -1277,7 +1050,7 @@ static void test_postcopy_common(MigrateCommon *args)
     if (migrate_postcopy_prepare(&from, &to, args)) {
         return;
     }
-    migrate_postcopy_start(from, to);
+    migrate_postcopy_start(from, to, &src_state);
     migrate_postcopy_complete(from, to, args);
 }
 
@@ -1464,7 +1237,7 @@ static void test_postcopy_recovery_common(MigrateCommon *args)
     migrate_set_parameter_int(from, "max-postcopy-bandwidth", 4096);
 
     /* Now we start the postcopy */
-    migrate_postcopy_start(from, to);
+    migrate_postcopy_start(from, to, &src_state);
 
     /*
      * Wait until postcopy is really started; we can only run the
@@ -1704,7 +1477,7 @@ static void test_precopy_common(MigrateCommon *args)
              * for some dirty mem before switching to converge
              */
             while (args->iterations > 1) {
-                wait_for_migration_pass(from);
+                wait_for_migration_pass(from, &src_state);
                 args->iterations--;
             }
             migrate_wait_for_dirty_mem(from, to);

tests/qtest/migration/migration-qmp.c

@@ -0,0 +1,485 @@
+/*
+ * QTest QMP helpers for migration
+ *
+ * Copyright (c) 2016-2018 Red Hat, Inc. and/or its affiliates
+ *   based on the vhost-user-test.c that is:
+ *      Copyright (c) 2014 Virtual Open Systems Sarl.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "libqtest.h"
+#include "migration-helpers.h"
+#include "migration-qmp.h"
+#include "qapi/error.h"
+#include "qapi/qmp/qdict.h"
+#include "qapi/qmp/qjson.h"
+#include "qapi/qmp/qlist.h"
+
+/*
+ * Number of seconds we wait when looking for migration
+ * status changes, to avoid test suite hanging forever
+ * when things go wrong. Needs to be higher enough to
+ * avoid false positives on loaded hosts.
+ */
+#define MIGRATION_STATUS_WAIT_TIMEOUT 120
+
+/*
+ * Wait for a "MIGRATION" event.  This is what Libvirt uses to track
+ * migration status changes.
+ */
+void migration_event_wait(QTestState *s, const char *target)
+{
+    QDict *response, *data;
+    const char *status;
+    bool found;
+
+    do {
+        response = qtest_qmp_eventwait_ref(s, "MIGRATION");
+        data = qdict_get_qdict(response, "data");
+        g_assert(data);
+        status = qdict_get_str(data, "status");
+        found = (strcmp(status, target) == 0);
+        qobject_unref(response);
+    } while (!found);
+}
+
+void migrate_qmp_fail(QTestState *who, const char *uri,
+                      const char *channels, const char *fmt, ...)
+{
+    va_list ap;
+    QDict *args, *err;
+
+    va_start(ap, fmt);
+    args = qdict_from_vjsonf_nofail(fmt, ap);
+    va_end(ap);
+
+    g_assert(!qdict_haskey(args, "uri"));
+    if (uri) {
+        qdict_put_str(args, "uri", uri);
+    }
+
+    g_assert(!qdict_haskey(args, "channels"));
+    if (channels) {
+        QObject *channels_obj = qobject_from_json(channels, &error_abort);
+        qdict_put_obj(args, "channels", channels_obj);
+    }
+
+    err = qtest_qmp_assert_failure_ref(
+        who, "{ 'execute': 'migrate', 'arguments': %p}", args);
+
+    g_assert(qdict_haskey(err, "desc"));
+
+    qobject_unref(err);
+}
+
+/*
+ * Send QMP command "migrate".
+ * Arguments are built from @fmt... (formatted like
+ * qobject_from_jsonf_nofail()) with "uri": @uri spliced in.
+ */
+void migrate_qmp(QTestState *who, QTestState *to, const char *uri,
+                 const char *channels, const char *fmt, ...)
+{
+    va_list ap;
+    QDict *args;
+    g_autofree char *connect_uri = NULL;
+
+    va_start(ap, fmt);
+    args = qdict_from_vjsonf_nofail(fmt, ap);
+    va_end(ap);
+
+    g_assert(!qdict_haskey(args, "uri"));
+    if (uri) {
+        qdict_put_str(args, "uri", uri);
+    } else if (!channels) {
+        connect_uri = migrate_get_connect_uri(to);
+        qdict_put_str(args, "uri", connect_uri);
+    }
+
+    g_assert(!qdict_haskey(args, "channels"));
+    if (channels) {
+        QObject *channels_obj = qobject_from_json(channels, &error_abort);
+        QList *channel_list = qobject_to(QList, channels_obj);
+        migrate_set_ports(to, channel_list);
+        qdict_put_obj(args, "channels", channels_obj);
+    }
+
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate', 'arguments': %p}", args);
+}
+
+void migrate_set_capability(QTestState *who, const char *capability,
+                            bool value)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-set-capabilities',"
+                             "'arguments': { "
+                             "'capabilities': [ { "
+                             "'capability': %s, 'state': %i } ] } }",
+                             capability, value);
+}
+
+void migrate_incoming_qmp(QTestState *to, const char *uri, const char *fmt, ...)
+{
+    va_list ap;
+    QDict *args, *rsp;
+
+    va_start(ap, fmt);
+    args = qdict_from_vjsonf_nofail(fmt, ap);
+    va_end(ap);
+
+    g_assert(!qdict_haskey(args, "uri"));
+    qdict_put_str(args, "uri", uri);
+
+    /* This function relies on the event to work, make sure it's enabled */
+    migrate_set_capability(to, "events", true);
+
+    rsp = qtest_qmp(to, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
+                    args);
+
+    if (!qdict_haskey(rsp, "return")) {
+        g_autoptr(GString) s = qobject_to_json_pretty(QOBJECT(rsp), true);
+        g_test_message("%s", s->str);
+    }
+
+    g_assert(qdict_haskey(rsp, "return"));
+    qobject_unref(rsp);
+
+    migration_event_wait(to, "setup");
+}
+
+static bool check_migration_status(QTestState *who, const char *goal,
+                                   const char **ungoals)
+{
+    bool ready;
+    char *current_status;
+    const char **ungoal;
+
+    current_status = migrate_query_status(who);
+    ready = strcmp(current_status, goal) == 0;
+    if (!ungoals) {
+        g_assert_cmpstr(current_status, !=, "failed");
+        /*
+         * If looking for a state other than completed,
+         * completion of migration would cause the test to
+         * hang.
+         */
+        if (strcmp(goal, "completed") != 0) {
+            g_assert_cmpstr(current_status, !=, "completed");
+        }
+    } else {
+        for (ungoal = ungoals; *ungoal; ungoal++) {
+            g_assert_cmpstr(current_status, !=,  *ungoal);
+        }
+    }
+    g_free(current_status);
+    return ready;
+}
+
+void wait_for_migration_status(QTestState *who,
+                               const char *goal, const char **ungoals)
+{
+    g_test_timer_start();
+    while (!check_migration_status(who, goal, ungoals)) {
+        usleep(1000);
+
+        g_assert(g_test_timer_elapsed() < MIGRATION_STATUS_WAIT_TIMEOUT);
+    }
+}
+
+void wait_for_migration_complete(QTestState *who)
+{
+    wait_for_migration_status(who, "completed", NULL);
+}
+
+void wait_for_migration_fail(QTestState *from, bool allow_active)
+{
+    g_test_timer_start();
+    QDict *rsp_return;
+    char *status;
+    bool failed;
+
+    do {
+        status = migrate_query_status(from);
+        bool result = !strcmp(status, "setup") || !strcmp(status, "failed") ||
+            (allow_active && !strcmp(status, "active"));
+        if (!result) {
+            fprintf(stderr, "%s: unexpected status status=%s allow_active=%d\n",
+                    __func__, status, allow_active);
+        }
+        g_assert(result);
+        failed = !strcmp(status, "failed");
+        g_free(status);
+
+        g_assert(g_test_timer_elapsed() < MIGRATION_STATUS_WAIT_TIMEOUT);
+    } while (!failed);
+
+    /* Is the machine currently running? */
+    rsp_return = qtest_qmp_assert_success_ref(from,
+                                              "{ 'execute': 'query-status' }");
+    g_assert(qdict_haskey(rsp_return, "running"));
+    g_assert(qdict_get_bool(rsp_return, "running"));
+    qobject_unref(rsp_return);
+}
+
+void wait_for_stop(QTestState *who, QTestMigrationState *state)
+{
+    if (!state->stop_seen) {
+        qtest_qmp_eventwait(who, "STOP");
+    }
+}
+
+void wait_for_resume(QTestState *who, QTestMigrationState *state)
+{
+    if (!state->resume_seen) {
+        qtest_qmp_eventwait(who, "RESUME");
+    }
+}
+
+void wait_for_suspend(QTestState *who, QTestMigrationState *state)
+{
+    if (state->suspend_me && !state->suspend_seen) {
+        qtest_qmp_eventwait(who, "SUSPEND");
+    }
+}
+
+/*
+ * Note: caller is responsible to free the returned object via
+ * qobject_unref() after use
+ */
+QDict *migrate_query(QTestState *who)
+{
+    return qtest_qmp_assert_success_ref(who, "{ 'execute': 'query-migrate' }");
+}
+
+QDict *migrate_query_not_failed(QTestState *who)
+{
+    const char *status;
+    QDict *rsp = migrate_query(who);
+    status = qdict_get_str(rsp, "status");
+    if (g_str_equal(status, "failed")) {
+        g_printerr("query-migrate shows failed migration: %s\n",
+                   qdict_get_str(rsp, "error-desc"));
+    }
+    g_assert(!g_str_equal(status, "failed"));
+    return rsp;
+}
+
+/*
+ * Note: caller is responsible to free the returned object via
+ * g_free() after use
+ */
+gchar *migrate_query_status(QTestState *who)
+{
+    QDict *rsp_return = migrate_query(who);
+    gchar *status = g_strdup(qdict_get_str(rsp_return, "status"));
+
+    g_assert(status);
+    qobject_unref(rsp_return);
+
+    return status;
+}
+
+int64_t read_ram_property_int(QTestState *who, const char *property)
+{
+    QDict *rsp_return, *rsp_ram;
+    int64_t result;
+
+    rsp_return = migrate_query_not_failed(who);
+    if (!qdict_haskey(rsp_return, "ram")) {
+        /* Still in setup */
+        result = 0;
+    } else {
+        rsp_ram = qdict_get_qdict(rsp_return, "ram");
+        result = qdict_get_try_int(rsp_ram, property, 0);
+    }
+    qobject_unref(rsp_return);
+    return result;
+}
+
+int64_t read_migrate_property_int(QTestState *who, const char *property)
+{
+    QDict *rsp_return;
+    int64_t result;
+
+    rsp_return = migrate_query_not_failed(who);
+    result = qdict_get_try_int(rsp_return, property, 0);
+    qobject_unref(rsp_return);
+    return result;
+}
+
+uint64_t get_migration_pass(QTestState *who)
+{
+    return read_ram_property_int(who, "dirty-sync-count");
+}
+
+void read_blocktime(QTestState *who)
+{
+    QDict *rsp_return;
+
+    rsp_return = migrate_query_not_failed(who);
+    g_assert(qdict_haskey(rsp_return, "postcopy-blocktime"));
+    qobject_unref(rsp_return);
+}
+
+/*
+ * Wait for two changes in the migration pass count, but bail if we stop.
+ */
+void wait_for_migration_pass(QTestState *who, QTestMigrationState *src_state)
+{
+    uint64_t pass, prev_pass = 0, changes = 0;
+
+    while (changes < 2 && !src_state->stop_seen && !src_state->suspend_seen) {
+        usleep(1000);
+        pass = get_migration_pass(who);
+        changes += (pass != prev_pass);
+        prev_pass = pass;
+    }
+}
+
+static long long migrate_get_parameter_int(QTestState *who,
+                                           const char *parameter)
+{
+    QDict *rsp;
+    long long result;
+
+    rsp = qtest_qmp_assert_success_ref(
+        who, "{ 'execute': 'query-migrate-parameters' }");
+    result = qdict_get_int(rsp, parameter);
+    qobject_unref(rsp);
+    return result;
+}
+
+static void migrate_check_parameter_int(QTestState *who, const char *parameter,
+                                        long long value)
+{
+    long long result;
+
+    result = migrate_get_parameter_int(who, parameter);
+    g_assert_cmpint(result, ==, value);
+}
+
+void migrate_set_parameter_int(QTestState *who, const char *parameter,
+                               long long value)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-set-parameters',"
+                             "'arguments': { %s: %lld } }",
+                             parameter, value);
+    migrate_check_parameter_int(who, parameter, value);
+}
+
+static char *migrate_get_parameter_str(QTestState *who, const char *parameter)
+{
+    QDict *rsp;
+    char *result;
+
+    rsp = qtest_qmp_assert_success_ref(
+        who, "{ 'execute': 'query-migrate-parameters' }");
+    result = g_strdup(qdict_get_str(rsp, parameter));
+    qobject_unref(rsp);
+    return result;
+}
+
+static void migrate_check_parameter_str(QTestState *who, const char *parameter,
+                                        const char *value)
+{
+    g_autofree char *result = migrate_get_parameter_str(who, parameter);
+    g_assert_cmpstr(result, ==, value);
+}
+
+void migrate_set_parameter_str(QTestState *who, const char *parameter,
+                               const char *value)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-set-parameters',"
+                             "'arguments': { %s: %s } }",
+                             parameter, value);
+    migrate_check_parameter_str(who, parameter, value);
+}
+
+static long long migrate_get_parameter_bool(QTestState *who,
+                                            const char *parameter)
+{
+    QDict *rsp;
+    int result;
+
+    rsp = qtest_qmp_assert_success_ref(
+        who, "{ 'execute': 'query-migrate-parameters' }");
+    result = qdict_get_bool(rsp, parameter);
+    qobject_unref(rsp);
+    return !!result;
+}
+
+static void migrate_check_parameter_bool(QTestState *who, const char *parameter,
+                                         int value)
+{
+    int result;
+
+    result = migrate_get_parameter_bool(who, parameter);
+    g_assert_cmpint(result, ==, value);
+}
+
+void migrate_set_parameter_bool(QTestState *who, const char *parameter,
+                                int value)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-set-parameters',"
+                             "'arguments': { %s: %i } }",
+                             parameter, value);
+    migrate_check_parameter_bool(who, parameter, value);
+}
+
+void migrate_ensure_non_converge(QTestState *who)
+{
+    /* Can't converge with 1ms downtime + 3 mbs bandwidth limit */
+    migrate_set_parameter_int(who, "max-bandwidth", 3 * 1000 * 1000);
+    migrate_set_parameter_int(who, "downtime-limit", 1);
+}
+
+void migrate_ensure_converge(QTestState *who)
+{
+    /* Should converge with 30s downtime + 1 gbs bandwidth limit */
+    migrate_set_parameter_int(who, "max-bandwidth", 1 * 1000 * 1000 * 1000);
+    migrate_set_parameter_int(who, "downtime-limit", 30 * 1000);
+}
+
+void migrate_pause(QTestState *who)
+{
+    qtest_qmp_assert_success(who, "{ 'execute': 'migrate-pause' }");
+}
+
+void migrate_continue(QTestState *who, const char *state)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-continue',"
+                             "  'arguments': { 'state': %s } }",
+                             state);
+}
+
+void migrate_recover(QTestState *who, const char *uri)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-recover', "
+                             "  'id': 'recover-cmd', "
+                             "  'arguments': { 'uri': %s } }",
+                             uri);
+}
+
+void migrate_cancel(QTestState *who)
+{
+    qtest_qmp_assert_success(who, "{ 'execute': 'migrate_cancel' }");
+}
+
+void migrate_postcopy_start(QTestState *from, QTestState *to,
+                            QTestMigrationState *src_state)
+{
+    qtest_qmp_assert_success(from, "{ 'execute': 'migrate-start-postcopy' }");
+
+    wait_for_stop(from, src_state);
+    qtest_qmp_eventwait(to, "RESUME");
+}

tests/qtest/migration/migration-qmp.h

@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef MIGRATION_QMP_H
+#define MIGRATION_QMP_H
+
+G_GNUC_PRINTF(4, 5)
+void migrate_qmp_fail(QTestState *who, const char *uri,
+                      const char *channels, const char *fmt, ...);
+
+G_GNUC_PRINTF(5, 6)
+void migrate_qmp(QTestState *who, QTestState *to, const char *uri,
+                 const char *channels, const char *fmt, ...);
+
+G_GNUC_PRINTF(3, 4)
+void migrate_incoming_qmp(QTestState *who, const char *uri,
+                          const char *fmt, ...);
+
+void migration_event_wait(QTestState *s, const char *target);
+void migrate_set_capability(QTestState *who, const char *capability,
+                            bool value);
+int64_t read_ram_property_int(QTestState *who, const char *property);
+void migrate_set_parameter_int(QTestState *who, const char *parameter,
+                               long long value);
+void wait_for_stop(QTestState *who, QTestMigrationState *state);
+void wait_for_resume(QTestState *who, QTestMigrationState *state);
+void wait_for_suspend(QTestState *who, QTestMigrationState *state);
+gchar *migrate_query_status(QTestState *who);
+int64_t read_migrate_property_int(QTestState *who, const char *property);
+uint64_t get_migration_pass(QTestState *who);
+void read_blocktime(QTestState *who);
+void wait_for_migration_pass(QTestState *who, QTestMigrationState *src_state);
+void migrate_set_parameter_str(QTestState *who, const char *parameter,
+                               const char *value);
+void migrate_set_parameter_bool(QTestState *who, const char *parameter,
+                                int value);
+void migrate_ensure_non_converge(QTestState *who);
+void migrate_ensure_converge(QTestState *who);
+void migrate_pause(QTestState *who);
+void migrate_continue(QTestState *who, const char *state);
+void migrate_recover(QTestState *who, const char *uri);
+void migrate_cancel(QTestState *who);
+void migrate_postcopy_start(QTestState *from, QTestState *to,
+                            QTestMigrationState *src_state);
+
+#endif /* MIGRATION_QMP_H */

tests/qtest/virtio-net-failover.c

@@ -12,6 +12,7 @@
 #include "libqos/pci.h"
 #include "libqos/pci-pc.h"
 #include "migration-helpers.h"
+#include "migration/migration-qmp.h"
 #include "qapi/qmp/qdict.h"
 #include "qapi/qmp/qlist.h"
 #include "qapi/qmp/qjson.h"