diff --git a/block/raw-posix.c b/block/raw-posix.c
index cd89c8312a..5241308d23 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -1363,7 +1363,7 @@ static int cdrom_eject(BlockDriverState *bs, int eject_flag)
     return 0;
 }
 
-static int cdrom_set_locked(BlockDriverState *bs, int locked)
+static void cdrom_set_locked(BlockDriverState *bs, int locked)
 {
     BDRVRawState *s = bs->opaque;
 
@@ -1374,8 +1374,6 @@ static int cdrom_set_locked(BlockDriverState *bs, int locked)
          */
         /* perror("CDROM_LOCKDOOR"); */
     }
-
-    return 0;
 }
 
 static BlockDriver bdrv_host_cdrom = {
@@ -1486,12 +1484,12 @@ static int cdrom_eject(BlockDriverState *bs, int eject_flag)
     return 0;
 }
 
-static int cdrom_set_locked(BlockDriverState *bs, int locked)
+static void cdrom_set_locked(BlockDriverState *bs, int locked)
 {
     BDRVRawState *s = bs->opaque;
 
     if (s->fd < 0)
-        return -ENOTSUP;
+        return;
     if (ioctl(s->fd, (locked ? CDIOCPREVENT : CDIOCALLOW)) < 0) {
         /*
          * Note: an error can happen if the distribution automatically
@@ -1499,8 +1497,6 @@ static int cdrom_set_locked(BlockDriverState *bs, int locked)
          */
         /* perror("CDROM_LOCKDOOR"); */
     }
-
-    return 0;
 }
 
 static BlockDriver bdrv_host_cdrom = {
diff --git a/block/raw.c b/block/raw.c
index b0f72d6a62..1398a9c221 100644
--- a/block/raw.c
+++ b/block/raw.c
@@ -80,10 +80,9 @@ static int raw_eject(BlockDriverState *bs, int eject_flag)
     return bdrv_eject(bs->file, eject_flag);
 }
 
-static int raw_set_locked(BlockDriverState *bs, int locked)
+static void raw_set_locked(BlockDriverState *bs, int locked)
 {
     bdrv_set_locked(bs->file, locked);
-    return 0;
 }
 
 static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
diff --git a/block_int.h b/block_int.h
index efb68038c4..e0b638c116 100644
--- a/block_int.h
+++ b/block_int.h
@@ -113,7 +113,7 @@ struct BlockDriver {
     int (*bdrv_is_inserted)(BlockDriverState *bs);
     int (*bdrv_media_changed)(BlockDriverState *bs);
     int (*bdrv_eject)(BlockDriverState *bs, int eject_flag);
-    int (*bdrv_set_locked)(BlockDriverState *bs, int locked);
+    void (*bdrv_set_locked)(BlockDriverState *bs, int locked);
 
     /* to control generic scsi devices */
     int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);