Re: [PATCHSET] block: fix PIO cache coherency bug, take 2

[James Bottomley]

On Mon, 2006-06-05 at 16:34 +0100, Russell King wrote:
> What has zero copy (your reply) got to do with faulting pages into
> userspace (my message).  I'm sorry, I don't understand why you've
> brought this up.

The zero copy case is the case where we end up with user and kernel
mappings simultaneously on the page.  The nopage (or fault) case is
where we end up with them sequentially.  Both cases actually require the
same cache treatment, but it's easiest to understand in the zero copy
case.

James


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/