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Date: Fri, 19 Apr 2013 09:27:43 -0300
From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
To: Mike Frysinger <vapier@gentoo.org>
Subject: Re: [RFC/PATCH v2] ubi: Add ubiblock read-write driver
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Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>,
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On Thu, Apr 18, 2013 at 09:28:16PM -0400, Mike Frysinger wrote:
> On Thursday 18 April 2013 20:13:00 Ezequiel Garcia wrote:
> > On Thu, Apr 18, 2013 at 04:30:55PM -0400, Mike Frysinger wrote:
> > > i wonder if the write support should be put behind a CONFIG option.
> > > personally, the write support is kind of neat and semi-useful for
> > > development, but i don't plan on shipping anything on that :).  i just
> > > want read-only support to load an ext2 fs on top of UBI.
> > 
> > Mmm... good input. Maybe putting write support behind a CONFIG and
> > showing a big fat warning when the module loads will do?
> > (something to prevent regular users from using this carelessly).
> > 
> > May I ask why would you want to put ext2 fs? Have you considered f2fs?
> 
> well, unless i misread things, f2fs is designed for consumer flash 
> (mmc/cf/etc...) where the flash (e.g. NAND) is behind a FTL.  the device i'm 
> interested isn't behind a FTL (the NAND is connected directly to the NAND 
> controller in the SoC),

Indeed f2fs is designed for flash behind FTL. The thing is the ubi+ubiblock
should act as a FTL, providing bad block management and wear leveling.

So that's why I've been wondering about using f2fs. Probably I should
give it a try and post the results, instead of just wondering.
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com