From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Tue, 26 Aug 2008 16:55:36 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Bruce Leonard <brucle@earthlink.net>
Subject: Re: [PATCH 2/2][MTD] Add support for > 2GiB MTD devices
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Cc: linux-mtd@lists.infradead.org, David Woodhouse <dwmw2@infradead.org>,
	linux-kernel@vger.kernel.org
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On Thu, 21 Aug 2008 19:00:55 -0700 (GMT-07:00)
Bruce Leonard <brucle@earthlink.net> wrote:

> --- a/include/mtd/mtd-abi.h
> +++ b/include/mtd/mtd-abi.h
> @@ -6,7 +6,7 @@
>  #define __MTD_ABI_H__
>  
>  struct erase_info_user {
> -	uint32_t start;
> +	uint64_t start;
>  	uint32_t length;
>  };
>  
> @@ -50,7 +50,7 @@ struct mtd_oob_buf {
>  struct mtd_info_user {
>  	uint8_t type;
>  	uint32_t flags;
> -	uint32_t size;	 // Total size of the MTD
> +	uint64_t size;	 // Total size of the MTD
>  	uint32_t erasesize;
>  	uint32_t writesize;
>  	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)

This changes the kernel<->userspace ABI and is hence a big no-no.  I
assume that this change will cause old userspace to malfunction on new
kernels, and vice versa.

Supporting >2Gb MTD devices sounds useful (I'm surprised that we don't
already do so).

Please cc linux-mtd@lists.infradead.org (at least) on MTD-related
patches, thanks.