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Subject: Re: Creating an ext3 partition on an mtd device
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Mark Ryden <markryde@gmail.com>
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Date: Thu, 27 Aug 2009 09:29:20 +0300
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Cc: Justin Waters <justin.waters@timesys.com>,
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On Thu, 2009-08-27 at 08:59 +0300, Mark Ryden wrote:
> Hello, Justin,
> Thanks for your answer.
> 
> Then why do I have in "Essential Linux Device Drivers" this , in
> "Block Device Emulation" section of chapter 17, "Memory Technology
> Devices" , this:
> 
> Block Device Emulation
> The MTD subsystem provides a block driver called mtdblock that
> emulates a hard disk over flash memory. You can put any filesystem,
> say EXT2, over the emulated flash disk. Mtdblock hides complicated
> flash access procedures (such as preceding a write with an erase of
> the corresponding sector) from the filesystem. Device nodes created by
> mtdblock are named /dev/mtdblock/X, where X is the partition number.
> To create an EXT2 filesystem on the pda_fs partition of the handheld,
> as shown in Figure 17.2, do the following:
> bash> mkfs.ext2 /dev/mtdblock/2                 Create an EXT2 filesystem
>                                                  on the second partition
> 
> bash> mount /dev/mtdblock/2 /mnt                Mount the partition

mtdblock does not do any bad block handling, so you cannot use it with
NAND. And it does not do any wear-leveling, and it has zero tolerance to
power cuts.

I think the text above assumes that you have NOR, you do not care about
WL and power-cuts.

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)