diff options
| -rw-r--r-- | block/qcow2.c | 43 |
1 files changed, 38 insertions, 5 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 60ed084e5c..af08757055 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -4912,12 +4912,46 @@ static int qcow2_downgrade(BlockDriverState *bs, int target_version, return 0; } +/* + * Upgrades an image's version. While newer versions encompass all + * features of older versions, some things may have to be presented + * differently. + */ +static int qcow2_upgrade(BlockDriverState *bs, int target_version, + BlockDriverAmendStatusCB *status_cb, void *cb_opaque, + Error **errp) +{ + BDRVQcow2State *s = bs->opaque; + int current_version = s->qcow_version; + int ret; + + /* This is qcow2_upgrade(), not qcow2_downgrade() */ + assert(target_version > current_version); + + /* There are no other versions (yet) that you can upgrade to */ + assert(target_version == 3); + + status_cb(bs, 0, 1, cb_opaque); + + s->qcow_version = target_version; + ret = qcow2_update_header(bs); + if (ret < 0) { + s->qcow_version = current_version; + error_setg_errno(errp, -ret, "Failed to update the image header"); + return ret; + } + status_cb(bs, 1, 1, cb_opaque); + + return 0; +} + typedef enum Qcow2AmendOperation { /* This is the value Qcow2AmendHelperCBInfo::last_operation will be * statically initialized to so that the helper CB can discern the first * invocation from an operation change */ QCOW2_NO_OPERATION = 0, + QCOW2_UPGRADING, QCOW2_CHANGING_REFCOUNT_ORDER, QCOW2_DOWNGRADING, } Qcow2AmendOperation; @@ -5100,17 +5134,16 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, helper_cb_info = (Qcow2AmendHelperCBInfo){ .original_status_cb = status_cb, .original_cb_opaque = cb_opaque, - .total_operations = (new_version < old_version) + .total_operations = (new_version != old_version) + (s->refcount_bits != refcount_bits) }; /* Upgrade first (some features may require compat=1.1) */ if (new_version > old_version) { - s->qcow_version = new_version; - ret = qcow2_update_header(bs); + helper_cb_info.current_operation = QCOW2_UPGRADING; + ret = qcow2_upgrade(bs, new_version, &qcow2_amend_helper_cb, + &helper_cb_info, errp); if (ret < 0) { - s->qcow_version = old_version; - error_setg_errno(errp, -ret, "Failed to update the image header"); return ret; } } |