Re: pte_page

[Brian Gerst <bgerst@didntduck.org>]

Brian Gerst wrote:
> 
> mdaljeet@in.ibm.com wrote:
> >
> > I use the 'pgt_offset', 'pmd_offset', 'pte_offset' and 'pte_page' inside a
> > module to get the physical address of a user space virtual address. The
> > physical address returned by 'pte_page' is not page aligned whereas the
> > virtual address was page aligned. Can somebody tell me the reason?
> >
> > Also, can i use these functions to get the physical address of a kernel
> > virtual address using init_mm?
> 
> pte_page() returns the struct page * for the page, not the page
> address.  To get the physical address of a page use __pa(virtaddr), but
> this works if and only if the page is not highmem and not vmalloced.

Oops, I forgot that you said user page...  __pa() only works for kernel
addresses.  I don't see any other macros that can help you.  Maybe one
of the VM gurus can add something here?

-- 

						Brian Gerst