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Subject: Re: CRC error when mounting UBIFS
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Leo Barnes <barnes.leo@gmail.com>
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Date: Fri, 04 Jun 2010 21:01:53 +0300
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On Fri, 2010-06-04 at 19:35 +0200, Leo Barnes wrote:
> > The way to fix this is to make UBI/UBIFS use arrays of pages instead. Or
> > array of 2, 4, 8, etc pages, or it may be flexible and contain a field
> > which describes the allocation order. And then UBI/UBIFS code should be
> > amended correspondingly.
> >
> > This will need some effort, but I think a skilled engineer would do this
> > relatively quickly. We are not actively working on UBI/UBIFS now, so we
> > will unlikely implement this, but I'd be happy to help someone else to
> > do this.
> >
> > Many people ask about small features like security xattrs, or NFS
> > support, or DMA friendliness, but it is strange that people want ready
> > solutions instead of investing a bit of time and just implementing this.
> 
> Sounds good, I might take a crack at it, I have been looking for some
> way to contribute to the linux kernel.
> 
> Have I understood the UBI code correctly in that only the
> ubi->peb_buf1, ubi->peb_buf2 and ubi->dbg_peb_buf are ever sent to the
> mtd->read/write functions? Currently at home and dont really have
> anything to test code in.

Yes, AFAIR. If you really will try to do this, let's discuss the
strategy.

> Does UBIFS ever access the mtd-layer directly?

No. In UBIFS getting rid of vmalloc will be more difficult because it'll
need to modify algorithms like GC which walks uses the buffers.

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)