This variable, along with its helpers, is used to detect whether multiple
channel will be supported for migration.  In follow up patches, there'll be
other capability that requires multi-channels.  Hence move it outside multifd
specific code and make it public.  Meanwhile rename it from "multifd" to
"multi_channels" to show its real meaning.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 migration/migration.c | 22 +++++++++++++++++-----
 migration/migration.h |  3 +++
 migration/multifd.c   | 19 ++++---------------
 migration/multifd.h   |  2 --
 4 files changed, 24 insertions(+), 22 deletions(-)

diff --git a/migration/migration.c b/migration/migration.c
index bcc385b94b..6e4cc9cc87 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -180,6 +180,18 @@ static int migration_maybe_pause(MigrationState *s,
                                  int new_state);
 static void migrate_fd_cancel(MigrationState *s);
 
+static bool migrate_allow_multi_channels = true;
+
+void migrate_protocol_allow_multi_channels(bool allow)
+{
+    migrate_allow_multi_channels = allow;
+}
+
+bool migrate_multi_channels_is_allowed(void)
+{
+    return migrate_allow_multi_channels;
+}
+
 static gint page_request_addr_cmp(gconstpointer ap, gconstpointer bp)
 {
     uintptr_t a = (uintptr_t) ap, b = (uintptr_t) bp;
@@ -463,12 +475,12 @@ static void qemu_start_incoming_migration(const char *uri, Error **errp)
 {
     const char *p = NULL;
 
-    migrate_protocol_allow_multifd(false); /* reset it anyway */
+    migrate_protocol_allow_multi_channels(false); /* reset it anyway */
     qapi_event_send_migration(MIGRATION_STATUS_SETUP);
     if (strstart(uri, "tcp:", &p) ||
         strstart(uri, "unix:", NULL) ||
         strstart(uri, "vsock:", NULL)) {
-        migrate_protocol_allow_multifd(true);
+        migrate_protocol_allow_multi_channels(true);
         socket_start_incoming_migration(p ? p : uri, errp);
 #ifdef CONFIG_RDMA
     } else if (strstart(uri, "rdma:", &p)) {
@@ -1255,7 +1267,7 @@ static bool migrate_caps_check(bool *cap_list,
 
     /* incoming side only */
     if (runstate_check(RUN_STATE_INMIGRATE) &&
-        !migrate_multifd_is_allowed() &&
+        !migrate_multi_channels_is_allowed() &&
         cap_list[MIGRATION_CAPABILITY_MULTIFD]) {
         error_setg(errp, "multifd is not supported by current protocol");
         return false;
@@ -2313,11 +2325,11 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
         }
     }
 
-    migrate_protocol_allow_multifd(false);
+    migrate_protocol_allow_multi_channels(false);
     if (strstart(uri, "tcp:", &p) ||
         strstart(uri, "unix:", NULL) ||
         strstart(uri, "vsock:", NULL)) {
-        migrate_protocol_allow_multifd(true);
+        migrate_protocol_allow_multi_channels(true);
         socket_start_outgoing_migration(s, p ? p : uri, &local_err);
 #ifdef CONFIG_RDMA
     } else if (strstart(uri, "rdma:", &p)) {
diff --git a/migration/migration.h b/migration/migration.h
index d8b9850eae..d677a750c9 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -429,4 +429,7 @@ void migration_cancel(const Error *error);
 void populate_vfio_info(MigrationInfo *info);
 void postcopy_temp_page_reset(PostcopyTmpPage *tmp_page);
 
+bool migrate_multi_channels_is_allowed(void);
+void migrate_protocol_allow_multi_channels(bool allow);
+
 #endif
diff --git a/migration/multifd.c b/migration/multifd.c
index 76b57a7177..180586dcde 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -517,7 +517,7 @@ void multifd_save_cleanup(void)
 {
     int i;
 
-    if (!migrate_use_multifd() || !migrate_multifd_is_allowed()) {
+    if (!migrate_use_multifd() || !migrate_multi_channels_is_allowed()) {
         return;
     }
     multifd_send_terminate_threads(NULL);
@@ -858,17 +858,6 @@ cleanup:
     multifd_new_send_channel_cleanup(p, sioc, local_err);
 }
 
-static bool migrate_allow_multifd = true;
-void migrate_protocol_allow_multifd(bool allow)
-{
-    migrate_allow_multifd = allow;
-}
-
-bool migrate_multifd_is_allowed(void)
-{
-    return migrate_allow_multifd;
-}
-
 int multifd_save_setup(Error **errp)
 {
     int thread_count;
@@ -879,7 +868,7 @@ int multifd_save_setup(Error **errp)
     if (!migrate_use_multifd()) {
         return 0;
     }
-    if (!migrate_multifd_is_allowed()) {
+    if (!migrate_multi_channels_is_allowed()) {
         error_setg(errp, "multifd is not supported by current protocol");
         return -1;
     }
@@ -980,7 +969,7 @@ int multifd_load_cleanup(Error **errp)
 {
     int i;
 
-    if (!migrate_use_multifd() || !migrate_multifd_is_allowed()) {
+    if (!migrate_use_multifd() || !migrate_multi_channels_is_allowed()) {
         return 0;
     }
     multifd_recv_terminate_threads(NULL);
@@ -1129,7 +1118,7 @@ int multifd_load_setup(Error **errp)
     if (!migrate_use_multifd()) {
         return 0;
     }
-    if (!migrate_multifd_is_allowed()) {
+    if (!migrate_multi_channels_is_allowed()) {
         error_setg(errp, "multifd is not supported by current protocol");
         return -1;
     }
diff --git a/migration/multifd.h b/migration/multifd.h
index 4dda900a0b..636e599395 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -13,8 +13,6 @@
 #ifndef QEMU_MIGRATION_MULTIFD_H
 #define QEMU_MIGRATION_MULTIFD_H
 
-bool migrate_multifd_is_allowed(void);
-void migrate_protocol_allow_multifd(bool allow);
 int multifd_save_setup(Error **errp);
 void multifd_save_cleanup(void);
 int multifd_load_setup(Error **errp);
-- 
2.32.0