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Date: Mon, 28 Jul 2014 10:49:54 +0800
From: hujianyang <hujianyang@huawei.com>
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To: Richard Weinberger <richard.weinberger@gmail.com>
Subject: Re: Using UBIFS as an FTL
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Cc: Daniel Ehrenberg <dehrenberg@google.com>,
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On 2014/7/27 15:20, Richard Weinberger wrote:
> On Sat, Jul 26, 2014 at 1:41 AM, hujianyang <hujianyang@huawei.com> wrote:
>> On 2014/7/26 2:21, Daniel Ehrenberg wrote:
>>> - loopback-mounting a file on ubifs--From skimming the code, it looks
>>> to me like ubifs uses some nice datastructures to handle writes within
>>> a file without doing read-modify-writes all the time as ubiblock
>>> forces. ubifs authors/maintainers, do you see any downside to using
>>> ubifs this way?
>>
>> This way seems most easily to realize. Synchronize the loop file and
>> maybe you will never worry about power cut.
>>
>> How about using UBI-layer and writing a new block driver to handle
>> bio? This driver should care about which leb on the flash has data
>> and other thing else(I don't have a clear idea now). The 'leb_change'
>> ops in UBI-layer maybe helpful for in-place update and atomic write.
>> But This way is harder than using a loop file.
> 
> Instead of adding another UBI block layer, please integrate such functionality
> in Ezequiel's UBI block.
> 

Oh, sorry~! I didn't know his work before. I should have done some
more researches.

Did you mean MTD_UBI_BLOCK? It seems a read-only interface. What's
your plan on it?

Add cc: Ezequiel Garcia

Richard, Thank you very much~!