From 83ac6a1ed40bfbe185cf2bac5505d8d97aad8b1d Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Sun, 27 Jul 2008 20:28:03 -0700 Subject: [PATCH] powerpc/mm: Implement _PAGE_SPECIAL & pte_special() for 64-bit Implement _PAGE_SPECIAL and pte_special() for 64-bit powerpc. This bit will be used by the fast get_user_pages() to differenciate PTEs that correspond to a valid struct page from special mappings that don't such as IO mappings obtained via io_remap_pfn_ranges(). Signed-off-by: Nick Piggin Acked-by: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Hugh Dickins Cc: "Paul E. McKenney" Reviewed-by: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Benjamin Herrenschmidt --- include/asm-powerpc/pgtable-4k.h | 2 ++ include/asm-powerpc/pgtable-64k.h | 2 ++ include/asm-powerpc/pgtable-ppc64.h | 4 ++-- 3 files changed, 6 insertions(+), 2 deletions(-) diff --git a/include/asm-powerpc/pgtable-4k.h b/include/asm-powerpc/pgtable-4k.h index c9601dfb4a..6b18ba9d2d 100644 --- a/include/asm-powerpc/pgtable-4k.h +++ b/include/asm-powerpc/pgtable-4k.h @@ -46,6 +46,8 @@ #define _PAGE_GROUP_IX 0x7000 /* software: HPTE index within group */ #define _PAGE_F_SECOND _PAGE_SECONDARY #define _PAGE_F_GIX _PAGE_GROUP_IX +#define _PAGE_SPECIAL 0x10000 /* software: special page */ +#define __HAVE_ARCH_PTE_SPECIAL /* PTE flags to conserve for HPTE identification */ #define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | \ diff --git a/include/asm-powerpc/pgtable-64k.h b/include/asm-powerpc/pgtable-64k.h index 7e54adb355..07b0d8f09c 100644 --- a/include/asm-powerpc/pgtable-64k.h +++ b/include/asm-powerpc/pgtable-64k.h @@ -70,6 +70,8 @@ static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd) #define PGDIR_MASK (~(PGDIR_SIZE-1)) /* Additional PTE bits (don't change without checking asm in hash_low.S) */ +#define __HAVE_ARCH_PTE_SPECIAL +#define _PAGE_SPECIAL 0x00000400 /* software: special page */ #define _PAGE_HPTE_SUB 0x0ffff000 /* combo only: sub pages HPTE bits */ #define _PAGE_HPTE_SUB0 0x08000000 /* combo only: first sub page */ #define _PAGE_COMBO 0x10000000 /* this is a combo 4k page */ diff --git a/include/asm-powerpc/pgtable-ppc64.h b/include/asm-powerpc/pgtable-ppc64.h index ba8000352b..5fc78c0be3 100644 --- a/include/asm-powerpc/pgtable-ppc64.h +++ b/include/asm-powerpc/pgtable-ppc64.h @@ -245,7 +245,7 @@ static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW;} static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY;} static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED;} static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE;} -static inline int pte_special(pte_t pte) { return 0; } +static inline int pte_special(pte_t pte) { return pte_val(pte) & _PAGE_SPECIAL; } static inline void pte_uncache(pte_t pte) { pte_val(pte) |= _PAGE_NO_CACHE; } static inline void pte_cache(pte_t pte) { pte_val(pte) &= ~_PAGE_NO_CACHE; } @@ -265,7 +265,7 @@ static inline pte_t pte_mkyoung(pte_t pte) { static inline pte_t pte_mkhuge(pte_t pte) { return pte; } static inline pte_t pte_mkspecial(pte_t pte) { - return pte; } + pte_val(pte) |= _PAGE_SPECIAL; return pte; } static inline unsigned long pte_pgprot(pte_t pte) { return __pgprot(pte_val(pte)) & PAGE_PROT_BITS; -- 2.39.5