Re: [Qemu-devel] [PATCH 3/5] block/qcow2-bitmap: don't remove bitmaps on reopen

[John Snow <jsnow@redhat.com>]

On 3/6/19 10:28 AM, Vladimir Sementsov-Ogievskiy wrote:
> 06.03.2019 2:43, John Snow wrote:
>> We tend to remove bitmaps when we flush them to disk, but it's not appropriate
>> in all cases. let the reopen mechanism use the lighter weight flush instead of
>> the heavier store.
>>
>> Signed-off-by: John Snow <jsnow@redhat.com>
>> ---
>>   block/qcow2-bitmap.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
>> index 4e11b6b05a..9373055d3b 100644
>> --- a/block/qcow2-bitmap.c
>> +++ b/block/qcow2-bitmap.c
>> @@ -1560,7 +1560,7 @@ int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp)
>>       BdrvDirtyBitmap *bitmap;
>>       Error *local_err = NULL;
>>   
>> -    qcow2_store_persistent_dirty_bitmaps(bs, &local_err);
>> +    qcow2_flush_persistent_dirty_bitmaps(bs, &local_err);
>>       if (local_err != NULL) {
>>           error_propagate(errp, local_err);
>>           return -EINVAL;
>>
> 
> 
> hmm will it work? if we call qcow2_open after that, it will fail to load bitmaps, as they
> are already exist
> 

Hmm, maybe you're right. I didn't test this very well. It seemed wrong
to me so I "fixed" it... let me write a test that covers this.