diff options
| -rw-r--r-- | block/mirror.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/block/mirror.c b/block/mirror.c index 05758e5500..2a4333474e 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -631,11 +631,49 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base, BlockDriverCompletionFunc *cb, void *opaque, Error **errp) { + int64_t length, base_length; + int orig_base_flags; + + orig_base_flags = bdrv_get_flags(base); + if (bdrv_reopen(base, bs->open_flags, errp)) { return; } + + length = bdrv_getlength(bs); + if (length < 0) { + error_setg(errp, "Unable to determine length of %s", bs->filename); + goto error_restore_flags; + } + + base_length = bdrv_getlength(base); + if (base_length < 0) { + error_setg(errp, "Unable to determine length of %s", base->filename); + goto error_restore_flags; + } + + if (length > base_length) { + if (bdrv_truncate(base, length) < 0) { + error_setg(errp, "Top image %s is larger than base image %s, and " + "resize of base image failed", + bs->filename, base->filename); + goto error_restore_flags; + } + } + bdrv_ref(base); mirror_start_job(bs, base, speed, 0, 0, on_error, on_error, cb, opaque, errp, &commit_active_job_driver, false, base); + if (error_is_set(errp)) { + goto error_restore_flags; + } + + return; + +error_restore_flags: + /* ignore error and errp for bdrv_reopen, because we want to propagate + * the original error */ + bdrv_reopen(base, orig_base_flags, NULL); + return; } |