block: enable in_use flag

Set block device in use during block migration, disallow drive_del and
bdrv_truncate for in use devices.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/block.c b/block.c
index ee9edfce2c..b476479e0d 100644
--- a/block.c
+++ b/block.c
@@ -1132,6 +1132,8 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset)
         return -ENOTSUP;
     if (bs->read_only)
         return -EACCES;
+    if (bdrv_in_use(bs))
+        return -EBUSY;
     ret = drv->bdrv_truncate(bs, offset);
     if (ret == 0) {
         ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);