diff options
Diffstat (limited to 'block')
-rw-r--r-- | block/qcow2.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 7fbef97aab..840f289a48 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -4384,14 +4384,17 @@ static int qcow2_make_empty(BlockDriverState *bs) if (s->qcow_version >= 3 && !s->snapshots && !s->nb_bitmaps && 3 + l1_clusters <= s->refcount_block_size && - s->crypt_method_header != QCOW_CRYPT_LUKS) { + s->crypt_method_header != QCOW_CRYPT_LUKS && + !has_data_file(bs)) { /* The following function only works for qcow2 v3 images (it * requires the dirty flag) and only as long as there are no * features that reserve extra clusters (such as snapshots, * LUKS header, or persistent bitmaps), because it completely * empties the image. Furthermore, the L1 table and three * additional clusters (image header, refcount table, one - * refcount block) have to fit inside one refcount block. */ + * refcount block) have to fit inside one refcount block. It + * only resets the image file, i.e. does not work with an + * external data file. */ return make_completely_empty(bs); } |