diff options
| author | Dave Hansen <dave@linux.vnet.ibm.com> | 2013-01-22 13:24:31 -0800 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2013-01-25 16:33:22 -0800 |
| commit | 4cbeb51b860c57ba8b2ae50c4016ee7a41f5fbd5 (patch) | |
| tree | bf51acd1c4e8c21b15e06fd87c646018efe5e0b2 | |
| parent | a25b9316841c5afa226f8f70a457861b35276a92 (diff) | |
x86, mm: Pagetable level size/shift/mask helpers
I plan to use lookup_address() to walk the kernel pagetables
in a later patch. It returns a "pte" and the level in the
pagetables where the "pte" was found. The level is just an
enum and needs to be converted to a useful value in order to
do address calculations with it. These helpers will be used
in at least two places.
This also gives the anonymous enum a real name so that no one
gets confused about what they should be passing in to these
helpers.
"PTE_SHIFT" was chosen for naming consistency with the other
pagetable levels (PGD/PUD/PMD_SHIFT).
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20130122212431.405D3A8C@kernel.stglabs.ibm.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| -rw-r--r-- | arch/x86/include/asm/pgtable.h | 14 | ||||
| -rw-r--r-- | arch/x86/include/asm/pgtable_types.h | 2 |
2 files changed, 15 insertions, 1 deletions
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 5199db2923d..bc28e6fe705 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -390,6 +390,7 @@ pte_t *populate_extra_pte(unsigned long vaddr); #ifndef __ASSEMBLY__ #include <linux/mm_types.h> +#include <linux/log2.h> static inline int pte_none(pte_t pte) { @@ -781,6 +782,19 @@ static inline void clone_pgd_range(pgd_t *dst, pgd_t *src, int count) memcpy(dst, src, count * sizeof(pgd_t)); } +#define PTE_SHIFT ilog2(PTRS_PER_PTE) +static inline int page_level_shift(enum pg_level level) +{ + return (PAGE_SHIFT - PTE_SHIFT) + level * PTE_SHIFT; +} +static inline unsigned long page_level_size(enum pg_level level) +{ + return 1UL << page_level_shift(level); +} +static inline unsigned long page_level_mask(enum pg_level level) +{ + return ~(page_level_size(level) - 1); +} #include <asm-generic/pgtable.h> #endif /* __ASSEMBLY__ */ diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 3c32db8c539..6c297e7998c 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -331,7 +331,7 @@ extern void native_pagetable_init(void); struct seq_file; extern void arch_report_meminfo(struct seq_file *m); -enum { +enum pg_level { PG_LEVEL_NONE, PG_LEVEL_4K, PG_LEVEL_2M, |