diff options
Diffstat (limited to 'arch/x86/mm/pgtable.c')
| -rw-r--r-- | arch/x86/mm/pgtable.c | 160 |
1 files changed, 150 insertions, 10 deletions
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 7b22adaad4f1..0b97d2c75df3 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -4,6 +4,7 @@ #include <asm/pgtable.h> #include <asm/tlb.h> #include <asm/fixmap.h> +#include <asm/mtrr.h> #define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO @@ -58,7 +59,7 @@ void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte) tlb_remove_page(tlb, pte); } -#if PAGETABLE_LEVELS > 2 +#if CONFIG_PGTABLE_LEVELS > 2 void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd) { struct page *page = virt_to_page(pmd); @@ -74,14 +75,14 @@ void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd) tlb_remove_page(tlb, page); } -#if PAGETABLE_LEVELS > 3 +#if CONFIG_PGTABLE_LEVELS > 3 void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud) { paravirt_release_pud(__pa(pud) >> PAGE_SHIFT); tlb_remove_page(tlb, virt_to_page(pud)); } -#endif /* PAGETABLE_LEVELS > 3 */ -#endif /* PAGETABLE_LEVELS > 2 */ +#endif /* CONFIG_PGTABLE_LEVELS > 3 */ +#endif /* CONFIG_PGTABLE_LEVELS > 2 */ static inline void pgd_list_add(pgd_t *pgd) { @@ -117,9 +118,9 @@ static void pgd_ctor(struct mm_struct *mm, pgd_t *pgd) /* If the pgd points to a shared pagetable level (either the ptes in non-PAE, or shared PMD in PAE), then just copy the references from swapper_pg_dir. */ - if (PAGETABLE_LEVELS == 2 || - (PAGETABLE_LEVELS == 3 && SHARED_KERNEL_PMD) || - PAGETABLE_LEVELS == 4) { + if (CONFIG_PGTABLE_LEVELS == 2 || + (CONFIG_PGTABLE_LEVELS == 3 && SHARED_KERNEL_PMD) || + CONFIG_PGTABLE_LEVELS == 4) { clone_pgd_range(pgd + KERNEL_PGD_BOUNDARY, swapper_pg_dir + KERNEL_PGD_BOUNDARY, KERNEL_PGD_PTRS); @@ -275,12 +276,87 @@ static void pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmds[]) } } +/* + * Xen paravirt assumes pgd table should be in one page. 64 bit kernel also + * assumes that pgd should be in one page. + * + * But kernel with PAE paging that is not running as a Xen domain + * only needs to allocate 32 bytes for pgd instead of one page. + */ +#ifdef CONFIG_X86_PAE + +#include <linux/slab.h> + +#define PGD_SIZE (PTRS_PER_PGD * sizeof(pgd_t)) +#define PGD_ALIGN 32 + +static struct kmem_cache *pgd_cache; + +static int __init pgd_cache_init(void) +{ + /* + * When PAE kernel is running as a Xen domain, it does not use + * shared kernel pmd. And this requires a whole page for pgd. + */ + if (!SHARED_KERNEL_PMD) + return 0; + + /* + * when PAE kernel is not running as a Xen domain, it uses + * shared kernel pmd. Shared kernel pmd does not require a whole + * page for pgd. We are able to just allocate a 32-byte for pgd. + * During boot time, we create a 32-byte slab for pgd table allocation. + */ + pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_ALIGN, + SLAB_PANIC, NULL); + if (!pgd_cache) + return -ENOMEM; + + return 0; +} +core_initcall(pgd_cache_init); + +static inline pgd_t *_pgd_alloc(void) +{ + /* + * If no SHARED_KERNEL_PMD, PAE kernel is running as a Xen domain. + * We allocate one page for pgd. + */ + if (!SHARED_KERNEL_PMD) + return (pgd_t *)__get_free_page(PGALLOC_GFP); + + /* + * Now PAE kernel is not running as a Xen domain. We can allocate + * a 32-byte slab for pgd to save memory space. + */ + return kmem_cache_alloc(pgd_cache, PGALLOC_GFP); +} + +static inline void _pgd_free(pgd_t *pgd) +{ + if (!SHARED_KERNEL_PMD) + free_page((unsigned long)pgd); + else + kmem_cache_free(pgd_cache, pgd); +} +#else +static inline pgd_t *_pgd_alloc(void) +{ + return (pgd_t *)__get_free_page(PGALLOC_GFP); +} + +static inline void _pgd_free(pgd_t *pgd) +{ + free_page((unsigned long)pgd); +} +#endif /* CONFIG_X86_PAE */ + pgd_t *pgd_alloc(struct mm_struct *mm) { pgd_t *pgd; pmd_t *pmds[PREALLOCATED_PMDS]; - pgd = (pgd_t *)__get_free_page(PGALLOC_GFP); + pgd = _pgd_alloc(); if (pgd == NULL) goto out; @@ -310,7 +386,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm) out_free_pmds: free_pmds(mm, pmds); out_free_pgd: - free_page((unsigned long)pgd); + _pgd_free(pgd); out: return NULL; } @@ -320,7 +396,7 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd) pgd_mop_up_pmds(mm, pgd); pgd_dtor(pgd); paravirt_pgd_free(mm, pgd); - free_page((unsigned long)pgd); + _pgd_free(pgd); } /* @@ -485,3 +561,67 @@ void native_set_fixmap(enum fixed_addresses idx, phys_addr_t phys, { __native_set_fixmap(idx, pfn_pte(phys >> PAGE_SHIFT, flags)); } + +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP +int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot) +{ + u8 mtrr; + + /* + * Do not use a huge page when the range is covered by non-WB type + * of MTRRs. + */ + mtrr = mtrr_type_lookup(addr, addr + PUD_SIZE); + if ((mtrr != MTRR_TYPE_WRBACK) && (mtrr != 0xFF)) + return 0; + + prot = pgprot_4k_2_large(prot); + + set_pte((pte_t *)pud, pfn_pte( + (u64)addr >> PAGE_SHIFT, + __pgprot(pgprot_val(prot) | _PAGE_PSE))); + + return 1; +} + +int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot) +{ + u8 mtrr; + + /* + * Do not use a huge page when the range is covered by non-WB type + * of MTRRs. + */ + mtrr = mtrr_type_lookup(addr, addr + PMD_SIZE); + if ((mtrr != MTRR_TYPE_WRBACK) && (mtrr != 0xFF)) + return 0; + + prot = pgprot_4k_2_large(prot); + + set_pte((pte_t *)pmd, pfn_pte( + (u64)addr >> PAGE_SHIFT, + __pgprot(pgprot_val(prot) | _PAGE_PSE))); + + return 1; +} + +int pud_clear_huge(pud_t *pud) +{ + if (pud_large(*pud)) { + pud_clear(pud); + return 1; + } + + return 0; +} + +int pmd_clear_huge(pmd_t *pmd) +{ + if (pmd_large(*pmd)) { + pmd_clear(pmd); + return 1; + } + + return 0; +} +#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ |