[dm-devel] block mapping

Kasatkin, Dmitry dmitry.kasatkin at intel.com
Thu Sep 29 14:27:45 UTC 2011


On Thu, Sep 29, 2011 at 5:19 PM, Zdenek Kabelac <zkabelac at redhat.com> wrote:
> Dne 29.9.2011 16:10, Kasatkin, Dmitry napsal(a):
>> Hello,
>>
>>
>> On Thu, Sep 29, 2011 at 4:42 PM, Zdenek Kabelac <zkabelac at redhat.com> wrote:
>>> Dne 29.9.2011 15:35, Kasatkin, Dmitry napsal(a):
>>>> Hello All,
>>>>
>>>> I would like to implement such block device, which can store
>>>> additional information along with the block data.
>>>> For example. so if file system has 4k block, I would like to store
>>>> 4k+256b of additional information...
>>>>
>>>> Can such block device be implemented with device mapper?
>>>>
>>>
>>> Yes - i.e.the old snapshot target stores the block and it's remapping info
>>> (thought the size info is much smaller then 256b)
>>>
>>
>> 1. Old snapshot target? Where is it...
>>
>
> kernel/drivers/md/dm-snap-persistent.c
>
>
>> 2. Isn't it stores some data at the beginning of the block device - in
>> the header..
>
> A bit more complicated that this - but yes, quite straightforward target.
>

Thanks

>
> Zdenek
>
> --
> dm-devel mailing list
> dm-devel at redhat.com
> https://www.redhat.com/mailman/listinfo/dm-devel
>




More information about the dm-devel mailing list