How to map a page with userland program?

[LI Xin]

John Baldwin wrote:
> On Friday 15 September 2006 10:26, LI Xin wrote:
>> Dear folks,
>>
>> Is there a continent and MI way to map a kernel page into userland 
>> address space under the same virtual address?  It seems that this can be 
>> implemented through some routines in MD part of pmap, but is it possible 
>> to use higher level VM routines to do the job?
> 
> Not to the same userland virtual address.  Why do you need the same
> virtual address anyway?  If it's for pointers use offsets relative to
> the start of the page instead.

That would make it easier to implement some sort of VSYSCALL, which is 
in fact executed in userland.  Or, is there any better way? :-)

Cheers,
-- 
Xin LI <delphij at delphij.net>	http://www.delphij.net/
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