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Subject: Re: ubiblock RW
To: Willy Tarreau <w@1wt.eu>
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Cc: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>,
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From: Richard Weinberger <richard@nod.at>
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Date: Mon, 28 Mar 2016 00:01:53 +0200
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Am 26.03.2016 um 07:01 schrieb Willy Tarreau:
> On Fri, Mar 25, 2016 at 10:25:17PM +0100, Richard Weinberger wrote:
>> Am 25.03.2016 um 21:50 schrieb Ezequiel Garcia:
>>> I guess we could have some UBI parameter to enable this support,
>>> and print a very noisy message to warn users about potential
>>> device wear out -- naively assuming users read messages...
>>
>> As I wrote in my previous mail, I think a new parameter for the ubiblock
>> tool would do the job.
>> I'd default ubiblock to RO and via the ubiblock tool you can enable RW mode.
>> ...which would also trigger a warning.
>>
>> What I'd like to avoid is a kernel command line or a Kconfig option to make
>> RW default. If someone *really* wants RW she has to run ubiblock --enable-rw....
>> in userspace. This should even work for block filesystems on top of UBI
>> as root fs as you can remount them later RW.
>>
>> Sounds like a plan?
> 
> I would see something a little bit better (from a user perspective), though
> I don't know if it's possible. It would be nice to mark the UBI image RO/RW
> when it is created via ubiformat. That would be a bit stored on the ubiblock
> itself. That way the decision is taken at creation time and is not changed
> later (or only using a specific tool). Note that it is very possible I'm
> missing something important, but you get the idea.

ubiblock is just a layer above an UBI volumes.
We could add a new UBI volume flag for RW ubiblock.

Artem? Ezequiel?

Thanks,
//richard