migrate_init: Call from savevm

Suspend to file is very much like a migrate, and it makes life
easier if we have the Migration state available, so initialise it
in the savevm.c code for suspending.

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

include/migration/migration.h

@@ -42,10 +42,7 @@ struct MigrationParams {
     bool shared;
 };
 
-typedef struct MigrationState MigrationState;
-
 typedef QLIST_HEAD(, LoadStateEntry) LoadStateEntry_Head;
-
 /* State for the incoming migration */
 struct MigrationIncomingState {
     QEMUFile *from_src_file;
@@ -116,6 +113,7 @@ int migrate_fd_close(MigrationState *s);
 
 void add_migration_state_change_notifier(Notifier *notify);
 void remove_migration_state_change_notifier(Notifier *notify);
+MigrationState *migrate_init(const MigrationParams *params);
 bool migration_in_setup(MigrationState *);
 bool migration_has_finished(MigrationState *);
 bool migration_has_failed(MigrationState *);

include/qemu/typedefs.h

@@ -44,6 +44,7 @@ typedef struct MemoryRegion MemoryRegion;
 typedef struct MemoryRegionSection MemoryRegionSection;
 typedef struct MigrationIncomingState MigrationIncomingState;
 typedef struct MigrationParams MigrationParams;
+typedef struct MigrationState MigrationState;
 typedef struct Monitor Monitor;
 typedef struct MouseTransformInfo MouseTransformInfo;
 typedef struct MSIMessage MSIMessage;

migration/migration.c

@@ -682,7 +682,7 @@ bool migration_has_failed(MigrationState *s)
             s->state == MIGRATION_STATUS_FAILED);
 }
 
-static MigrationState *migrate_init(const MigrationParams *params)
+MigrationState *migrate_init(const MigrationParams *params)
 {
     MigrationState *s = migrate_get_current();
     int64_t bandwidth_limit = s->bandwidth_limit;

migration/savevm.c

@@ -922,6 +922,8 @@ static int qemu_savevm_state(QEMUFile *f, Error **errp)
         .blk = 0,
         .shared = 0
     };
+    MigrationState *ms = migrate_init(&params);
+    ms->file = f;
 
     if (qemu_savevm_state_blocked(errp)) {
         return -EINVAL;