Commit-ID: 4cbeb51b860c57ba8b2ae50c4016ee7a41f5fbd5 Gitweb: http://git.kernel.org/tip/4cbeb51b860c57ba8b2ae50c4016ee7a41f5fbd5 Author: Dave Hansen <d...@linux.vnet.ibm.com> AuthorDate: Tue, 22 Jan 2013 13:24:31 -0800 Committer: H. Peter Anvin <h...@linux.intel.com> CommitDate: Fri, 25 Jan 2013 16:33:22 -0800
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 <h...@zytor.com> Signed-off-by: Dave Hansen <d...@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20130122212431.405d3...@kernel.stglabs.ibm.com Signed-off-by: H. Peter Anvin <h...@linux.intel.com> --- arch/x86/include/asm/pgtable.h | 14 ++++++++++++++ arch/x86/include/asm/pgtable_types.h | 2 +- 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 5199db2..bc28e6f 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 3c32db8..6c297e7 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, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
