Re: [PATCH] Btrfs-progs: fsck: disable --init-extent-tree option when using snapshots

Wang Shilong
2014-03-11T01:25:15Z

On 03/10/2014 11:50 PM, Josef Bacik wrote:
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> On 03/10/2014 08:12 AM, Shilong Wang wrote:
>> Hi Josef,
>>
>> As i haven't thought any better ideas to rebuild extent tree which
>> contains extent that owns 'FULL BACKREF' flag.
>>
>> Considering an extent's refs can be equal or more than 1 if this
>> extent has *FULL BACKREF* flag, so we could not make sure an
>> extent's flag by only searching fs/file tree any more.
>>
>> So until now, i just disable this option if snapshots exists,
>> please correct me if i miss something here. Or you have any better
>> ideas to solve this problem.~_~
>>
>>
> I thought the fsck stuff rebuilds full backref refs properly, does it
> not? If it doesn't we need to fix that, however I'm fine with
> disabling the option if snapshots exist for the time being. Thanks,
If there are no snapshots, --init-extent-tree can works as expected.
I just have not thought a better idea to rebuild extent tree if we do have
snapshots which means we may have an extent with *FULL BACKREF*
flag.

Thanks,
Wang
>
> Josef
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