Re: virt_to_page for userspace pointers

From: Nikolaus Rath
Date: Sun Feb 13 2011 - 15:30:31 EST


On 02/05/2011 04:36 PM, Brice Goglin wrote:
>> Is there an equivalent function to virt_to_page (and virt_to_phys) that
>> works with userspace pointers? Or do I have to manually walk through the
>> page tables? In the later case, are there any examples of this kind of
>> search that I could use as a basis?
>>
>
> You probably want get_user_pages() (or get_user_pages_fast()).

Thanks for the pointer, that already helped a lot!

I would, however, prefer a more primitive function that just gives me
the struct page without locking it. And if the page is swapped out, I'd
rather get a NULL pointer than having a page frame allocated. Is there
anything like that?

Thanks,

-Nikolaus

--
ÂTime flies like an arrow, fruit flies like a Banana.Â

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