make load_vmstate() return errors

Signed-off-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

monitor.c

@@ -1727,8 +1727,7 @@ static void do_loadvm(Monitor *mon, const char *name)
 
     vm_stop(0);
 
-    load_vmstate(mon, name);
-    if (saved_vm_running)
+    if (load_vmstate(mon, name) >= 0 && saved_vm_running)
         vm_start();
 }
 

savevm.c

@@ -1174,7 +1174,7 @@ void do_savevm(Monitor *mon, const char *name)
         vm_start();
 }
 
-void load_vmstate(Monitor *mon, const char *name)
+int load_vmstate(Monitor *mon, const char *name)
 {
     DriveInfo *dinfo;
     BlockDriverState *bs, *bs1;
@@ -1185,7 +1185,7 @@ void load_vmstate(Monitor *mon, const char *name)
     bs = get_bs_snapshots();
     if (!bs) {
         monitor_printf(mon, "No block device supports snapshots\n");
-        return;
+        return -EINVAL;
     }
 
     /* Flush all IO requests so they don't interfere with the new state.  */
@@ -1216,7 +1216,7 @@ void load_vmstate(Monitor *mon, const char *name)
                 }
                 /* fatal on snapshot block device */
                 if (bs == bs1)
-                    return;
+                    return 0;
             }
         }
     }
@@ -1224,19 +1224,21 @@ void load_vmstate(Monitor *mon, const char *name)
     /* Don't even try to load empty VM states */
     ret = bdrv_snapshot_find(bs, &sn, name);
     if ((ret >= 0) && (sn.vm_state_size == 0))
-        return;
+        return -EINVAL;
 
     /* restore the VM state */
     f = qemu_fopen_bdrv(bs, 0);
     if (!f) {
         monitor_printf(mon, "Could not open VM state file\n");
-        return;
+        return -EINVAL;
     }
     ret = qemu_loadvm_state(f);
     qemu_fclose(f);
     if (ret < 0) {
         monitor_printf(mon, "Error %d while loading VM state\n", ret);
+        return ret;
     }
+    return 0;
 }
 
 void do_delvm(Monitor *mon, const char *name)

sysemu.h

@@ -51,7 +51,7 @@ extern qemu_irq qemu_system_powerdown;
 void qemu_system_reset(void);
 
 void do_savevm(Monitor *mon, const char *name);
-void load_vmstate(Monitor *mon, const char *name);
+int load_vmstate(Monitor *mon, const char *name);
 void do_delvm(Monitor *mon, const char *name);
 void do_info_snapshots(Monitor *mon);
 

vl.c

@@ -6030,8 +6030,11 @@ int main(int argc, char **argv, char **envp)
         exit(1);
     }
 
-    if (loadvm)
-        load_vmstate(cur_mon, loadvm);
+    if (loadvm) {
+        if (load_vmstate(cur_mon, loadvm) < 0) {
+            autostart = 0;
+        }
+    }
 
     if (incoming) {
         qemu_start_incoming_migration(incoming);