migration: pre_save return int

Modify the pre_save method on VMStateDescription to return an int
rather than void so that it potentially can fail.

Changed zillions of devices to make them return 0; the only
case I've made it return non-0 is hw/intc/s390_flic_kvm.c that already
had an error_report/return case.

Note: If you add an error exit in your pre_save you must emit
an error_report to say why.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170925112917.21340-2-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/hw/usb/dev-smartcard-reader.c b/hw/usb/dev-smartcard-reader.c
index bef1f03c42..0c77d2a41d 100644
--- a/hw/usb/dev-smartcard-reader.c
+++ b/hw/usb/dev-smartcard-reader.c
@@ -1374,7 +1374,7 @@ static int ccid_post_load(void *opaque, int version_id)
     return 0;
 }
 
-static void ccid_pre_save(void *opaque)
+static int ccid_pre_save(void *opaque)
 {
     USBCCIDState *s = opaque;
 
@@ -1386,6 +1386,8 @@ static void ccid_pre_save(void *opaque)
          */
         s->migration_state = MIGRATION_MIGRATED;
     }
+
+    return 0;
 }
 
 static VMStateDescription bulk_in_vmstate = {