]> pilppa.com Git - linux-2.6-omap-h63xx.git/commit
x86: add _PAGE_IOMAP pte flag for IO mappings
authorJeremy Fitzhardinge <jeremy@goop.org>
Sun, 7 Sep 2008 22:21:13 +0000 (15:21 -0700)
committerIngo Molnar <mingo@elte.hu>
Mon, 13 Oct 2008 08:20:56 +0000 (10:20 +0200)
commitbe43d72835ba610e4af274f2d123b26f66f4f7ed
tree004fe651aff85c6cfae6a174217b05d948b7cf6d
parent07bb2f6236f11169fbd8a8916b16715b25fea9b6
x86: add _PAGE_IOMAP pte flag for IO mappings

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.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/mm/init_32.c
arch/x86/mm/init_64.c
arch/x86/mm/ioremap.c
include/asm-x86/pgtable.h