From: Max Reitz <[email protected]> In discard_single_l2(), we completely discard normal clusters instead of simply turning them into preallocated zero clusters. That means we should probably do the same with such preallocated zero clusters: Discard them instead of keeping them allocated.
Reported-by: Eric Blake <[email protected]> Signed-off-by: Max Reitz <[email protected]> Reviewed-by: Eric Blake <[email protected]> Signed-off-by: Kevin Wolf <[email protected]> --- block/qcow2-cluster.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index fb91fd8..31077d8 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1511,7 +1511,8 @@ static int discard_single_l2(BlockDriverState *bs, uint64_t offset, break; case QCOW2_CLUSTER_ZERO: - if (!full_discard) { + /* Preallocated zero clusters should be discarded in any case */ + if (!full_discard && (old_l2_entry & L2E_OFFSET_MASK) == 0) { continue; } break; -- 1.8.3.1
