text: #ifndef _ASM_X86_PGTABLE_DEFS_H
  #define _ASM_X86_PGTABLE_DEFS_H
  
  #include <linux/const.h>
  #include <asm/page_types.h>
  
  #define FIRST_USER_ADDRESS	0
  
  #define _PAGE_BIT_PRESENT	0	/* is present */
  #define _PAGE_BIT_RW		1	/* writeable */
  #define _PAGE_BIT_USER		2	/* userspace addressable */
  #define _PAGE_BIT_PWT		3	/* page write through */
  #define _PAGE_BIT_PCD		4	/* page cache disabled */
  #define _PAGE_BIT_ACCESSED	5	/* was accessed (raised by CPU) */
  #define _PAGE_BIT_DIRTY		6	/* was written to (raised by CPU) */
  #define _PAGE_BIT_PSE		7	/* 4 MB (or 2MB) page */
  #define _PAGE_BIT_PAT		7	/* on 4KB pages */
  #define _PAGE_BIT_GLOBAL	8	/* Global TLB entry PPro+ */
  #define _PAGE_BIT_UNUSED1	9	/* available for programmer */
  #define _PAGE_BIT_IOMAP		10	/* flag used to indicate IO mapping */
  #define _PAGE_BIT_HIDDEN	11	/* hidden by kmemcheck */
  #define _PAGE_BIT_PAT_LARGE	12	/* On 2MB or 1GB pages */
  #define _PAGE_BIT_SPECIAL	_PAGE_BIT_UNUSED1
  #define _PAGE_BIT_CPA_TEST	_PAGE_BIT_UNUSED1
  #define _PAGE_BIT_NX           63       /* No execute: only valid after cpuid check */
  
  /* If _PAGE_BIT_PRESENT is clear, we use these: */
  /* - if the user mapped it with PROT_NONE; pte_present gives true */
  #define _PAGE_BIT_PROTNONE	_PAGE_BIT_GLOBAL
  /* - set: nonlinear file mapping, saved PTE; unset:swap */
  #define _PAGE_BIT_FILE		_PAGE_BIT_DIRTY
  
  #define _PAGE_PRESENT	(_AT(pteval_t, 1) << _PAGE_BIT_PRESENT)
  #define _PAGE_RW	(_AT(pteval_t, 1) << _PAGE_BIT_RW)
  #define _PAGE_USER	(_AT(pteval_t, 1) << _PAGE_BIT_USER)
  #define _PAGE_PWT	(_AT(pteval_t, 1) << _PAGE_BIT_PWT)
  #define _PAGE_PCD	(_AT(pteval_t, 1) << _PAGE_BIT_PCD)
  #define _PAGE_ACCESSED	(_AT(pteval_t, 1) << _PAGE_BIT_ACCESSED)
  #define _PAGE_DIRTY	(_AT(pteval_t, 1) << _PAGE_BIT_DIRTY)
  #define _PAGE_PSE	(_AT(pteval_t, 1) << _PAGE_BIT_PSE)
  #define _PAGE_GLOBAL	(_AT(pteval_t, 1) << _PAGE_BIT_GLOBAL)
  #define _PAGE_UNUSED1	(_AT(pteval_t, 1) << _PAGE_BIT_UNUSED1)
  #define _PAGE_IOMAP	(_AT(pteval_t, 1) << _PAGE_BIT_IOMAP)
  #define _PAGE_PAT	(_AT(pteval_t, 1) << _PAGE_BIT_PAT)
  #define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE)
  #define _PAGE_SPECIAL	(_AT(pteval_t, 1) << _PAGE_BIT_SPECIAL)
  #define _PAGE_CPA_TEST	(_AT(pteval_t, 1) << _PAGE_BIT_CPA_TEST)
  #define __HAVE_ARCH_PTE_SPECIAL
  
  #ifdef CONFIG_KMEMCHECK
  #define _PAGE_HIDDEN	(_AT(pteval_t, 1) << _PAGE_BIT_HIDDEN)
  #else
  #define _PAGE_HIDDEN	(_AT(pteval_t, 0))
  #endif
  
  #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
  #define _PAGE_NX	(_AT(pteval_t, 1) << _PAGE_BIT_NX)
  #else
  #define _PAGE_NX	(_AT(pteval_t, 0))
  #endif
  
  #define _PAGE_FILE	(_AT(pteval_t, 1) << _PAGE_BIT_FILE)
  #define _PAGE_PROTNONE	(_AT(pteval_t, 1) << _PAGE_BIT_PROTNONE)
  
  #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER |	\
  			 _PAGE_ACCESSED | _PAGE_DIRTY)
  #define _KERNPG_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED |	\
  			 _PAGE_DIRTY)
  
  /* Set of bits not changed in pte_modify */
  #define _PAGE_CHG_MASK	(PTE_PFN_MASK | _PAGE_PCD | _PAGE_PWT |		\
  			 _PAGE_SPECIAL | _PAGE_ACCESSED | _PAGE_DIRTY)
  
  #define _PAGE_CACHE_MASK	(_PAGE_PCD | _PAGE_PWT)
  #define _PAGE_CACHE_WB		(0)
  #define _PAGE_CACHE_WC		(_PAGE_PWT)
  #define _PAGE_CACHE_UC_MINUS	(_PAGE_PCD)
  #define _PAGE_CACHE_UC		(_PAGE_PCD | _PAGE_PWT)
  
  #define PAGE_NONE	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
  #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
  				 _PAGE_ACCESSED | _PAGE_NX)
  
  #define PAGE_SHARED_EXEC	__pgprot(_PAGE_PRESENT | _PAGE_RW |	\
  					 _PAGE_USER | _PAGE_ACCESSED)
  #define PAGE_COPY_NOEXEC	__pgprot(_PAGE_PRESENT | _PAGE_USER |	\
  					 _PAGE_ACCESSED | _PAGE_NX)
  #define PAGE_COPY_EXEC		__pgprot(_PAGE_PRESENT | _PAGE_USER |	\
  					 _PAGE_ACCESSED)
  #define PAGE_COPY		PAGE_COPY_NOEXEC
  #define PAGE_READONLY		__pgprot(_PAGE_PRESENT | _PAGE_USER |	\
  					 _PAGE_ACCESSED | _PAGE_NX)
  #define PAGE_READONLY_EXEC	__pgprot(_PAGE_PRESENT | _PAGE_USER |	\
  					 _PAGE_ACCESSED)
  
  #define __PAGE_KERNEL_EXEC						\
  	(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_GLOBAL)
  #define __PAGE_KERNEL		(__PAGE_KERNEL_EXEC | _PAGE_NX)
  
  #define __PAGE_KERNEL_RO		(__PAGE_KERNEL & ~_PAGE_RW)
  #define __PAGE_KERNEL_RX		(__PAGE_KERNEL_EXEC & ~_PAGE_RW)
  #define __PAGE_KERNEL_EXEC_NOCACHE	(__PAGE_KERNEL_EXEC | _PAGE_PCD | _PAGE_PWT)
  #define __PAGE_KERNEL_WC		(__PAGE_KERNEL | _PAGE_CACHE_WC)
  #define __PAGE_KERNEL_NOCACHE		(__PAGE_KERNEL | _PAGE_PCD | _PAGE_PWT)
  #define __PAGE_KERNEL_UC_MINUS		(__PAGE_KERNEL | _PAGE_PCD)
  #define __PAGE_KERNEL_VSYSCALL		(__PAGE_KERNEL_RX | _PAGE_USER)
  #define __PAGE_KERNEL_VSYSCALL_NOCACHE	(__PAGE_KERNEL_VSYSCALL | _PAGE_PCD | _PAGE_PWT)
  #define __PAGE_KERNEL_LARGE		(__PAGE_KERNEL | _PAGE_PSE)
  #define __PAGE_KERNEL_LARGE_NOCACHE	(__PAGE_KERNEL | _PAGE_CACHE_UC | _PAGE_PSE)
  #define __PAGE_KERNEL_LARGE_EXEC	(__PAGE_KERNEL_EXEC | _PAGE_PSE)
  
  #define __PAGE_KERNEL_IO		(__PAGE_KERNEL | _PAGE_IOMAP)
  #define __PAGE_KERNEL_IO_NOCACHE	(__PAGE_KERNEL_NOCACHE | _PAGE_IOMAP)
  #define __PAGE_KERNEL_IO_UC_MINUS	(__PAGE_KERNEL_UC_MINUS | _PAGE_IOMAP)
  #define __PAGE_KERNEL_IO_WC		(__PAGE_KERNEL_WC | _PAGE_IOMAP)
  
  #define PAGE_KERNEL			__pgprot(__PAGE_KERNEL)
  #define PAGE_KERNEL_RO			__pgprot(__PAGE_KERNEL_RO)
  #define PAGE_KERNEL_EXEC		__pgprot(__PAGE_KERNEL_EXEC)
  #define PAGE_KERNEL_RX			__pgprot(__PAGE_KERNEL_RX)
  #define PAGE_KERNEL_WC			__pgprot(__PAGE_KERNEL_WC)
  #define PAGE_KERNEL_NOCACHE		__pgprot(__PAGE_KERNEL_NOCACHE)
  #define PAGE_KERNEL_UC_MINUS		__pgprot(__PAGE_KERNEL_UC_MINUS)
  #define PAGE_KERNEL_EXEC_NOCACHE	__pgprot(__PAGE_KERNEL_EXEC_NOCACHE)
  #define PAGE_KERNEL_LARGE		__pgprot(__PAGE_KERNEL_LARGE)
  #define PAGE_KERNEL_LARGE_NOCACHE	__pgprot(__PAGE_KERNEL_LARGE_NOCACHE)
  #define PAGE_KERNEL_LARGE_EXEC		__pgprot(__PAGE_KERNEL_LARGE_EXEC)
  #define PAGE_KERNEL_VSYSCALL		__pgprot(__PAGE_KERNEL_VSYSCALL)
  #define PAGE_KERNEL_VSYSCALL_NOCACHE	__pgprot(__PAGE_KERNEL_VSYSCALL_NOCACHE)
  
  #define PAGE_KERNEL_IO			__pgprot(__PAGE_KERNEL_IO)
  #define PAGE_KERNEL_IO_NOCACHE		__pgprot(__PAGE_KERNEL_IO_NOCACHE)
  #define PAGE_KERNEL_IO_UC_MINUS		__pgprot(__PAGE_KERNEL_IO_UC_MINUS)
  #define PAGE_KERNEL_IO_WC		__pgprot(__PAGE_KERNEL_IO_WC)
  
  /*         xwr */
  #define __P000	PAGE_NONE
  #define __P001	PAGE_READONLY
  #define __P010	PAGE_COPY
  #define __P011	PAGE_COPY
  #define __P100	PAGE_READONLY_EXEC
  #define __P101	PAGE_READONLY_EXEC
  #define __P110	PAGE_COPY_EXEC
  #define __P111	PAGE_COPY_EXEC
  
  #define __S000	PAGE_NONE
  #define __S001	PAGE_READONLY
  #define __S010	PAGE_SHARED
  #define __S011	PAGE_SHARED
  #define __S100	PAGE_READONLY_EXEC
  #define __S101	PAGE_READONLY_EXEC
  #define __S110	PAGE_SHARED_EXEC
  #define __S111	PAGE_SHARED_EXEC
  
  /*
   * early identity mapping  pte attrib macros.
   */
  #ifdef CONFIG_X86_64
  #define __PAGE_KERNEL_IDENT_LARGE_EXEC	__PAGE_KERNEL_LARGE_EXEC
  #else
  /*
   * For PDE_IDENT_ATTR include USER bit. As the PDE and PTE protection
   * bits are combined, this will alow user to access the high address mapped
   * VDSO in the presence of CONFIG_COMPAT_VDSO
   */
  #define PTE_IDENT_ATTR	 0x003		/* PRESENT+RW */
  #define PDE_IDENT_ATTR	 0x067		/* PRESENT+RW+USER+DIRTY+ACCESSED */
  #define PGD_IDENT_ATTR	 0x001		/* PRESENT (no other attributes) */
  #endif
  
  #ifdef CONFIG_X86_32
  # include "pgtable_32_types.h"
  #else
  # include "pgtable_64_types.h"
  #endif
  
  #ifndef __ASSEMBLY__
  
  #include <linux/types.h>
  
  /* PTE_PFN_MASK extracts the PFN from a (pte|pmd|pud|pgd)val_t */
  #define PTE_PFN_MASK		((pteval_t)PHYSICAL_PAGE_MASK)
  
  /* PTE_FLAGS_MASK extracts the flags from a (pte|pmd|pud|pgd)val_t */
  #define PTE_FLAGS_MASK		(~PTE_PFN_MASK)
  
  typedef struct pgprot { pgprotval_t pgprot; } pgprot_t;
  
  typedef struct { pgdval_t pgd; } pgd_t;
  
  static inline pgd_t native_make_pgd(pgdval_t val)
  {
  	return (pgd_t) { val };
  }
  
  static inline pgdval_t native_pgd_val(pgd_t pgd)
  {
  	return pgd.pgd;
  }
  
  static inline pgdval_t pgd_flags(pgd_t pgd)
  {
  	return native_pgd_val(pgd) & PTE_FLAGS_MASK;
  }
  
  #if PAGETABLE_LEVELS > 3
  typedef struct { pudval_t pud; } pud_t;
  
  static inline pud_t native_make_pud(pmdval_t val)
  {
  	return (pud_t) { val };
  }
  
  static inline pudval_t native_pud_val(pud_t pud)
  {
  	return pud.pud;
  }
  #else
  #include <asm-generic/pgtable-nopud.h>
  
  static inline pudval_t native_pud_val(pud_t pud)
  {
  	return native_pgd_val(pud.pgd);
  }
  #endif
  
  #if PAGETABLE_LEVELS > 2
  typedef struct { pmdval_t pmd; } pmd_t;
  
  static inline pmd_t native_make_pmd(pmdval_t val)
  {
  	return (pmd_t) { val };
  }
  
  static inline pmdval_t native_pmd_val(pmd_t pmd)
  {
  	return pmd.pmd;
  }
  #else
  #include <asm-generic/pgtable-nopmd.h>
  
  static inline pmdval_t native_pmd_val(pmd_t pmd)
  {
  	return native_pgd_val(pmd.pud.pgd);
  }
  #endif
  
  static inline pudval_t pud_flags(pud_t pud)
  {
  	return native_pud_val(pud) & PTE_FLAGS_MASK;
  }
  
  static inline pmdval_t pmd_flags(pmd_t pmd)
  {
  	return native_pmd_val(pmd) & PTE_FLAGS_MASK;
  }
  
  static inline pte_t native_make_pte(pteval_t val)
  {
  	return (pte_t) { .pte = val };
  }
  
  static inline pteval_t native_pte_val(pte_t pte)
  {
  	return pte.pte;
  }
  
  static inline pteval_t pte_flags(pte_t pte)
  {
  	return native_pte_val(pte) & PTE_FLAGS_MASK;
  }
  
  #define pgprot_val(x)	((x).pgprot)
  #define __pgprot(x)	((pgprot_t) { (x) } )
  
  
  typedef struct page *pgtable_t;
  
  extern pteval_t __supported_pte_mask;
  extern void set_nx(void);
  extern int nx_enabled;
  
  #define pgprot_writecombine	pgprot_writecombine
  extern pgprot_t pgprot_writecombine(pgprot_t prot);
  
  /* Indicate that x86 has its own track and untrack pfn vma functions */
  #define __HAVE_PFNMAP_TRACKING
  
  #define __HAVE_PHYS_MEM_ACCESS_PROT
  struct file;
  pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
                                unsigned long size, pgprot_t vma_prot);
  int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
                                unsigned long size, pgprot_t *vma_prot);
  
  /* Install a pte for a particular vaddr in kernel space. */
  void set_pte_vaddr(unsigned long vaddr, pte_t pte);
  
  #ifdef CONFIG_X86_32
  extern void native_pagetable_setup_start(pgd_t *base);
  extern void native_pagetable_setup_done(pgd_t *base);
  #else
  #define native_pagetable_setup_start x86_init_pgd_noop
  #define native_pagetable_setup_done  x86_init_pgd_noop
  #endif
  
  struct seq_file;
  extern void arch_report_meminfo(struct seq_file *m);
  
  enum {
  	PG_LEVEL_NONE,
  	PG_LEVEL_4K,
  	PG_LEVEL_2M,
  	PG_LEVEL_1G,
  	PG_LEVEL_NUM
  };
  
  #ifdef CONFIG_PROC_FS
  extern void update_page_count(int level, unsigned long pages);
  #else
  static inline void update_page_count(int level, unsigned long pages) { }
  #endif
  
  /*
   * Helper function that returns the kernel pagetable entry controlling
   * the virtual address 'address'. NULL means no pagetable entry present.
   * NOTE: the return type is pte_t but if the pmd is PSE then we return it
   * as a pte too.
   */
  extern pte_t *lookup_address(unsigned long address, unsigned int *level);
  
  #endif	/* !__ASSEMBLY__ */
  
  #endif /* _ASM_X86_PGTABLE_DEFS_H */
  