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-rw-r--r--arch/x86/include/asm/pgtable_32.h191
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
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+++ b/arch/x86/include/asm/pgtable_32.h
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+#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 */