Create MigrationIncomingState

There are currently lots of pieces of incoming migration state scattered
around, and postcopy is adding more, and it seems better to try and keep
it together.

allocate MIS in process_incoming_migration_co

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

include/migration/migration.h

@@ -42,6 +42,15 @@ struct MigrationParams {
 
 typedef struct MigrationState MigrationState;
 
+/* State for the incoming migration */
+struct MigrationIncomingState {
+    QEMUFile *file;
+};
+
+MigrationIncomingState *migration_incoming_get_current(void);
+MigrationIncomingState *migration_incoming_state_new(QEMUFile *f);
+void migration_incoming_state_destroy(void);
+
 struct MigrationState
 {
     int64_t bandwidth_limit;

include/qemu/typedefs.h

@@ -38,6 +38,7 @@ typedef struct MemoryListener MemoryListener;
 typedef struct MemoryMappingList MemoryMappingList;
 typedef struct MemoryRegion MemoryRegion;
 typedef struct MemoryRegionSection MemoryRegionSection;
+typedef struct MigrationIncomingState MigrationIncomingState;
 typedef struct MigrationParams MigrationParams;
 typedef struct Monitor Monitor;
 typedef struct MouseTransformInfo MouseTransformInfo;

migration/migration.c

@@ -53,6 +53,7 @@ static bool deferred_incoming;
    migrations at once.  For now we don't need to add
    dynamic creation of migration */
 
+/* For outgoing */
 MigrationState *migrate_get_current(void)
 {
     static MigrationState current_migration = {
@@ -71,6 +72,28 @@ MigrationState *migrate_get_current(void)
     return &current_migration;
 }
 
+/* For incoming */
+static MigrationIncomingState *mis_current;
+
+MigrationIncomingState *migration_incoming_get_current(void)
+{
+    return mis_current;
+}
+
+MigrationIncomingState *migration_incoming_state_new(QEMUFile* f)
+{
+    mis_current = g_malloc0(sizeof(MigrationIncomingState));
+    mis_current->file = f;
+
+    return mis_current;
+}
+
+void migration_incoming_state_destroy(void)
+{
+    g_free(mis_current);
+    mis_current = NULL;
+}
+
 /*
  * Called on -incoming with a defer: uri.
  * The migration can be started later after any parameters have been
@@ -115,9 +138,14 @@ static void process_incoming_migration_co(void *opaque)
     Error *local_err = NULL;
     int ret;
 
+    migration_incoming_state_new(f);
+
     ret = qemu_loadvm_state(f);
+
     qemu_fclose(f);
     free_xbzrle_decoded_buf();
+    migration_incoming_state_destroy();
+
     if (ret < 0) {
         error_report("load of migration failed: %s", strerror(-ret));
         migrate_decompress_threads_join();

migration/savevm.c

@@ -1329,9 +1329,11 @@ int load_vmstate(const char *name)
     }
 
     qemu_system_reset(VMRESET_SILENT);
+    migration_incoming_state_new(f);
     ret = qemu_loadvm_state(f);
 
     qemu_fclose(f);
+    migration_incoming_state_destroy();
     if (ret < 0) {
         error_report("Error %d while loading VM state", ret);
         return ret;