lkml.org 
[lkml]   [2008]   [Sep]   [9]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
DateTue, 09 Sep 2008 16:32:16 +0300
FromAvi Kivity <>
SubjectRe: [PATCH 1 of 7] x86: add _PAGE_IOMAP pte flag for IO mappings
Jeremy Fitzhardinge wrote:
> Use one of the software-defined PTE bits to indicate that a mapping is
> intended for an IO address.  On native hardware this is irrelevent,
> since a physical address is a physical address.  But in a virtual
> environment, physical addresses are also virtualized, so there needs
> to be some way to distinguish between pseudo-physical addresses and
> actual hardware addresses; _PAGE_IOMAP indicates this intent.
>
> By default, __supported_pte_mask masks out _PAGE_IOMAP, so it doesn't
> even appear in the final pagetable.
> 

Could PTE_SPECIAL, added for get_user_pages_really_fast(), be reused for 
this?

-- 
error compiling committee.c: too many arguments to function



\
 
 \ /
  Last update: 2008-09-09 15:35    [from the cache]
©2003-2008