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Date: Tue, 16 Aug 2005 13:56:47 +0400
From: "Artem B. Bityuckiy" <dedekind@yandex.ru>
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Cc: linux-mtd@lists.infradead.org
Subject: Re: [PATCH]fs/jffs2/wbuf.c: add compatibility support for OOB data
 block
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J=F6rn Engel wrote:
> Your approach, imo, is fundamentally borked because it requires
> high-order allocations.  Your array of physical pages has to be a
> contiguous virtual memory area, which won't always work.  And if you
> want to maintain a list of pages instead, you end up with the same
> design as with an array of slab objects, just one level higher and
> with another indirection.  Whatever the performance is, the code will
> be ugly.

I meant something like:

objs_per_page =3D PAGE_SIZE / sizeof(struct jffs2_eraseblock);
pages_num =3D c->blocks_nr / objs_per_page;

for (i =3D 0; i < pages_num; i++) {
     page =3D alloc_pages(flags, 0);
     c->blocks[i] =3D page_address(page);
}

So c->blocks[] is an array of pages. Nonetheless, I have never done=20
things like this before, may be there is some cleverer method exists...

--=20
Best Regards,
Artem B. Bityuckiy,
St.-Petersburg, Russia.