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Date: Sat, 26 Jul 2014 07:41:57 +0800
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To: Daniel Ehrenberg <dehrenberg@google.com>
Subject: Re: Using UBIFS as an FTL
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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.