Commit b464fce5 authored by Kumar Gala's avatar Kumar Gala Committed by Linus Torvalds
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[PATCH] ppc32: Allow adjust of pfn offset in pte 



Allow the pfn to be offset by more than just PAGE_SHIFT in the pte.  Today,
PAGE_SHIFT tends to allow us to have 12-bits of flags in the pte.  In the
future if we have a larger pte we can allocate more bits for flags by
offsetting the pfn even further.

Signed-off-by: default avatarKumar Gala <kumar.gala@freescale.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent a85f6d4a

include/asm-ppc/pgtable.h

+7 −2
Original line number Diff line number Diff line
@@ -431,10 +431,15 @@ extern unsigned long bad_call_to_PMD_PAGE_SIZE(void); 
 * Conversions between PTE values and page frame numbers.

 */



#define pte_pfn(x)		(pte_val(x) >> PAGE_SHIFT)

/* in some case we want to additionaly adjust where the pfn is in the pte to

 * allow room for more flags */

#define PFN_SHIFT_OFFSET	(PAGE_SHIFT)



#define pte_pfn(x)		(pte_val(x) >> PFN_SHIFT_OFFSET)

#define pte_page(x)		pfn_to_page(pte_pfn(x))



#define pfn_pte(pfn, prot)	__pte(((pte_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))

#define pfn_pte(pfn, prot)	__pte(((pte_basic_t)(pfn) << PFN_SHIFT_OFFSET) |\

					pgprot_val(prot))

#define mk_pte(page, prot)	pfn_pte(page_to_pfn(page), prot)



/*