diff options
| -rw-r--r-- | block/qcow2.c | 31 |
1 files changed, 16 insertions, 15 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 381b4f7ed3..07a4f0bab2 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3006,20 +3006,13 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, desc++; } - if (new_version != old_version) { - if (new_version > old_version) { - /* Upgrade */ - s->qcow_version = new_version; - ret = qcow2_update_header(bs); - if (ret < 0) { - s->qcow_version = old_version; - return ret; - } - } else { - ret = qcow2_downgrade(bs, new_version, status_cb, cb_opaque); - if (ret < 0) { - return ret; - } + /* Upgrade first (some features may require compat=1.1) */ + if (new_version > old_version) { + s->qcow_version = new_version; + ret = qcow2_update_header(bs); + if (ret < 0) { + s->qcow_version = old_version; + return ret; } } @@ -3034,7 +3027,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, if (s->use_lazy_refcounts != lazy_refcounts) { if (lazy_refcounts) { - if (s->qcow_version < 3) { + if (new_version < 3) { error_report("Lazy refcounts only supported with compatibility " "level 1.1 and above (use compat=1.1 or greater)"); return -EINVAL; @@ -3070,6 +3063,14 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, } } + /* Downgrade last (so unsupported features can be removed before) */ + if (new_version < old_version) { + ret = qcow2_downgrade(bs, new_version, status_cb, cb_opaque); + if (ret < 0) { + return ret; + } + } + return 0; } |