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Diffstat (limited to 'arch/x86/include/asm/pgtable_32.h')
-rw-r--r-- | arch/x86/include/asm/pgtable_32.h | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/arch/x86/include/asm/pgtable_32.h b/arch/x86/include/asm/pgtable_32.h new file mode 100644 index 0000000..8de702d --- /dev/null +++ b/arch/x86/include/asm/pgtable_32.h @@ -0,0 +1,191 @@ +#ifndef ASM_X86__PGTABLE_32_H +#define ASM_X86__PGTABLE_32_H + + +/* + * The Linux memory management assumes a three-level page table setup. On + * the i386, we use that, but "fold" the mid level into the top-level page + * table, so that we physically have the same two-level page table as the + * i386 mmu expects. + * + * This file contains the functions and defines necessary to modify and use + * the i386 page table tree. + */ +#ifndef __ASSEMBLY__ +#include <asm/processor.h> +#include <asm/fixmap.h> +#include <linux/threads.h> +#include <asm/paravirt.h> + +#include <linux/bitops.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/spinlock.h> + +struct mm_struct; +struct vm_area_struct; + +extern pgd_t swapper_pg_dir[1024]; + +static inline void pgtable_cache_init(void) { } +static inline void check_pgt_cache(void) { } +void paging_init(void); + +extern void set_pmd_pfn(unsigned long, unsigned long, pgprot_t); + +/* + * The Linux x86 paging architecture is 'compile-time dual-mode', it + * implements both the traditional 2-level x86 page tables and the + * newer 3-level PAE-mode page tables. + */ +#ifdef CONFIG_X86_PAE +# include <asm/pgtable-3level-defs.h> +# define PMD_SIZE (1UL << PMD_SHIFT) +# define PMD_MASK (~(PMD_SIZE - 1)) +#else +# include <asm/pgtable-2level-defs.h> +#endif + +#define PGDIR_SIZE (1UL << PGDIR_SHIFT) +#define PGDIR_MASK (~(PGDIR_SIZE - 1)) + +/* Just any arbitrary offset to the start of the vmalloc VM area: the + * current 8MB value just means that there will be a 8MB "hole" after the + * physical memory until the kernel virtual memory starts. That means that + * any out-of-bounds memory accesses will hopefully be caught. + * The vmalloc() routines leaves a hole of 4kB between each vmalloced + * area for the same reason. ;) + */ +#define VMALLOC_OFFSET (8 * 1024 * 1024) +#define VMALLOC_START ((unsigned long)high_memory + VMALLOC_OFFSET) +#ifdef CONFIG_X86_PAE +#define LAST_PKMAP 512 +#else +#define LAST_PKMAP 1024 +#endif + +#define PKMAP_BASE ((FIXADDR_BOOT_START - PAGE_SIZE * (LAST_PKMAP + 1)) \ + & PMD_MASK) + +#ifdef CONFIG_HIGHMEM +# define VMALLOC_END (PKMAP_BASE - 2 * PAGE_SIZE) +#else +# define VMALLOC_END (FIXADDR_START - 2 * PAGE_SIZE) +#endif + +#define MAXMEM (VMALLOC_END - PAGE_OFFSET - __VMALLOC_RESERVE) + +/* + * Define this if things work differently on an i386 and an i486: + * it will (on an i486) warn about kernel memory accesses that are + * done without a 'access_ok(VERIFY_WRITE,..)' + */ +#undef TEST_ACCESS_OK + +/* The boot page tables (all created as a single array) */ +extern unsigned long pg0[]; + +#define pte_present(x) ((x).pte_low & (_PAGE_PRESENT | _PAGE_PROTNONE)) + +/* To avoid harmful races, pmd_none(x) should check only the lower when PAE */ +#define pmd_none(x) (!(unsigned long)pmd_val((x))) +#define pmd_present(x) (pmd_val((x)) & _PAGE_PRESENT) +#define pmd_bad(x) ((pmd_val(x) & (PTE_FLAGS_MASK & ~_PAGE_USER)) != _KERNPG_TABLE) + +#define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT)) + +#ifdef CONFIG_X86_PAE +# include <asm/pgtable-3level.h> +#else +# include <asm/pgtable-2level.h> +#endif + +/* + * Macro to mark a page protection value as "uncacheable". + * On processors which do not support it, this is a no-op. + */ +#define pgprot_noncached(prot) \ + ((boot_cpu_data.x86 > 3) \ + ? (__pgprot(pgprot_val(prot) | _PAGE_PCD | _PAGE_PWT)) \ + : (prot)) + +/* + * Conversion functions: convert a page and protection to a page entry, + * and a page entry and page directory to the page they refer to. + */ +#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot)) + + +static inline int pud_large(pud_t pud) { return 0; } + +/* + * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD] + * + * this macro returns the index of the entry in the pmd page which would + * control the given virtual address + */ +#define pmd_index(address) \ + (((address) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) + +/* + * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE] + * + * this macro returns the index of the entry in the pte page which would + * control the given virtual address + */ +#define pte_index(address) \ + (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) +#define pte_offset_kernel(dir, address) \ + ((pte_t *)pmd_page_vaddr(*(dir)) + pte_index((address))) + +#define pmd_page(pmd) (pfn_to_page(pmd_val((pmd)) >> PAGE_SHIFT)) + +#define pmd_page_vaddr(pmd) \ + ((unsigned long)__va(pmd_val((pmd)) & PTE_PFN_MASK)) + +#if defined(CONFIG_HIGHPTE) +#define pte_offset_map(dir, address) \ + ((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), KM_PTE0) + \ + pte_index((address))) +#define pte_offset_map_nested(dir, address) \ + ((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), KM_PTE1) + \ + pte_index((address))) +#define pte_unmap(pte) kunmap_atomic((pte), KM_PTE0) +#define pte_unmap_nested(pte) kunmap_atomic((pte), KM_PTE1) +#else +#define pte_offset_map(dir, address) \ + ((pte_t *)page_address(pmd_page(*(dir))) + pte_index((address))) +#define pte_offset_map_nested(dir, address) pte_offset_map((dir), (address)) +#define pte_unmap(pte) do { } while (0) +#define pte_unmap_nested(pte) do { } while (0) +#endif + +/* Clear a kernel PTE and flush it from the TLB */ +#define kpte_clear_flush(ptep, vaddr) \ +do { \ + pte_clear(&init_mm, (vaddr), (ptep)); \ + __flush_tlb_one((vaddr)); \ +} while (0) + +/* + * The i386 doesn't have any external MMU info: the kernel page + * tables contain all the necessary information. + */ +#define update_mmu_cache(vma, address, pte) do { } while (0) + +#endif /* !__ASSEMBLY__ */ + +/* + * kern_addr_valid() is (1) for FLATMEM and (0) for + * SPARSEMEM and DISCONTIGMEM + */ +#ifdef CONFIG_FLATMEM +#define kern_addr_valid(addr) (1) +#else +#define kern_addr_valid(kaddr) (0) +#endif + +#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \ + remap_pfn_range(vma, vaddr, pfn, size, prot) + +#endif /* ASM_X86__PGTABLE_32_H */ |