Re: [PATCH/RFC] MTD: Striping layer core

Artem B. Bityutskiy
2006-03-31T08:03:12Z

Alexander Belyakov wrote:
>> Well, probably this is a perversion and is not needed in reality, but
>> still. I conceive it like this. Yo have 2 flashes. You as usually,
>> calculate the resulting eraseblock size. You see at the minimal I/O unit
>> size of both flashes and similarly calculate the resulting minimal I/O
>> size. So that's it. You'll end up with a though perverted, but still a
>> striped MTD device.
>
> First problem in case of striping NOR and NAND is a question about type
> of striped device. Should we report it as NOR or as NAND. I believe it
> is important for clients to know about that. Imagine, for example,
> device reported as NAND behaves as NOR or vice versa. Another problem is
> a difference in operation speed. Apparently you won't get any
> performance gain. These are only top of iceberg. Note that even plain
> and simple mtdconcat is not supposed to work with flashes of different
> types.

Good question. I think you could report this is a striped device
(introducing an MTD_STRIPED option). Also you may provide a
stripe_get_info(struct mtd_info *mtd) function which will return a
struct stripe_info object describing this striped device, including the
components it consists of.

--
Best Regards,
Artem B. Bityutskiy,
St.-Petersburg, Russia.