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Subject: Re: [PATCH 1/7] UBI: Add a new ioctl to support ubidump
From: Artem Bityutskiy <dedekind1@gmail.com>
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To: hujianyang <hujianyang@huawei.com>
Date: Wed, 16 Jul 2014 13:30:56 +0300
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On Wed, 2014-07-16 at 16:47 +0800, hujianyang wrote:
> Hi Artem,
> 
> Thank you for reviewing these patches.
> 
> > 
> > Do you really need to dump UBI headers?
> >
> 
> Yes, because I think ec_counter in ec_hdr and copy_flag, sqnum
> in vid_hdr are useful.
> 
> Current ->read() can just read data from data_offset where the
> leb located. And reading UBI headers by mtd functionality are
> very complicated, we don't know pnum either.
> 
> Maybe we can try other way instead of this ioctl, by adding an
> new function which can read the hole peb specified by lnum to
> user space.

Yes, this is a lot better approach. But I'd still suggest to start with
a smaller step - ubidump without the UBI headers dumping support. Then
add the UBI headers dumping support as a separate step.

-- 
Best Regards,
Artem Bityutskiy