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Date: Wed, 20 Feb 2008 18:22:50 +0100
From: =?utf-8?B?SsO2cm4=?= Engel <joern@logfs.org>
To: Stephane Chazelas <stephane.chazelas@emerson.com>
Cc: =?utf-8?B?SsO2cm4=?= Engel <joern@logfs.org>,
       Arnd Bergmann <arnd@arndb.de>, linux-kernel@vger.kernel.org,
       linux-mtd@lists.infradead.org
Subject: Re: [PATCH 2.6.24] block2mtd: removing a device and typo fixes
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On Wed, 20 February 2008 17:02:31 +0000, Stephane Chazelas wrote:
> 
> sorry, I wasn't very clear.
> 
> With "loop", you're doing an ioctl() to /dev/loop<x> so that
> /dev/loop<x> become a block device associated with a given file.
> 
> Applying that strictly to block2mtd wouldn't make sense.
> 
> At the moment, when you create a new block2mtd, the only thing
> you see is an entry in /proc/mtd.
> 
> You don't access that mtd device directly (there's no
> /dev/mtd<x>). Instead, you may access it via a /dev/mtdblock<x>
> if you have "block2mtd" for instance.

Actually, there is /dev/mtd<x>.  Enable CONFIG_MTD_CHAR.

> Here, what you need, is an API that gets a block device (with fd
> or path) and an erase size and that returns a mtd identifier.

Erase size is a real difference, agreed.  Otherwise the loop analogy is
quite good.  Occasionally people are asking for file->mtd translation as
well.

Jörn

-- 
To announce that there must be no criticism of the President, or that we
are to stand by the President, right or wrong, is not only unpatriotic
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