virt_to_page for userspace pointers (was: Reversing a memory mapping?)

From: Nikolaus Rath
Date: Sat Feb 05 2011 - 16:08:23 EST


Nikolaus Rath <Nikolaus@xxxxxxxx> writes:
> Is there a way that my own kernel module can "reverse" this mmap call?
> I.e. given the userspace pointer, how do I get access to the physical
> location of the memory that has been mapped?

Ok, after some studying I think I can ask the question in a better way:

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?


Thanks,

-Nikolaus

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

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