Re: [Linux-ia64] Re: Status on ioremap patch

Steffen Persvold
2002-01-09T20:01:13Z

Steffen Persvold wrote:
>
> David Mosberger wrote:
> >
> > Steffen,
> >
> > I looked at your patch and have a comment and a suggestion. First, I
> > do not think it's safe to define ioremap() as a way to install
> > write-cached mappings. There are plenty of drivers left that use
> > ioremap() instead of ioremap_nocache() and we can't change the
> > semantics of ioremap() underneath them.
> >
> > Second, it seems to me it would be cleaner to extend
> > remap_page_range() to allow remapping into the kernel mapped segment
> > (region 5 in the case of ia64 linux). This should work as is, except
> > that in the kernel case, you need to use pgd_offset_k(). I think you
> > could hack mm/memory.c to check whether "from" is in the range from
> > VMALLOC_START to VMALLOC_END and, if so, use pgd_offset_k() instead of
> > pgd_offset(). Can you try this and let me know if it works for your
> > needs?
> >
>
> I've had some time to look at it, and I decided to do what you said. I also changed ioremap on all
> platforms that implements it so that they use remap_page_range()). I've tested the patch on IA64 and
> i386.
>
> I've attached the patch (I didn't post it on the lkml even though it affects more that the IA64
> platform), it's against a vanilla 2.4.17 tree.
>
> Please take a look and tell me what you think.
>

So, what about this patch (posted earlier) David ? Have you seen the comments from Keith ?

Regards,
--
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