x86: add and use pgd/pud/pmd_flags

[deliverable/linux.git] / arch / x86 / include / asm / pgtable.h

#ifndef _ASM_X86_PGTABLE_H
#define _ASM_X86_PGTABLE_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_UNUSED3       11
#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_UNUSED3   (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED3)
#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

#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

/*
 * Macro to mark a page protection value as UC-
 */
#define pgprot_noncached(prot)                                  \
        ((boot_cpu_data.x86 > 3)                                \
         ? (__pgprot(pgprot_val(prot) | _PAGE_CACHE_UC_MINUS))  \
         : (prot))

#ifndef __ASSEMBLY__

#define pgprot_writecombine     pgprot_writecombine
extern pgprot_t pgprot_writecombine(pgprot_t prot);

/*
 * ZERO_PAGE is a global shared page that is always zero: used
 * for zero-mapped memory areas etc..
 */
extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))

extern spinlock_t pgd_lock;
extern struct list_head pgd_list;

/*
 * The following only work if pte_present() is true.
 * Undefined behaviour if not..
 */
static inline int pte_dirty(pte_t pte)
{
        return pte_flags(pte) & _PAGE_DIRTY;
}

static inline int pte_young(pte_t pte)
{
        return pte_flags(pte) & _PAGE_ACCESSED;
}

static inline int pte_write(pte_t pte)
{
        return pte_flags(pte) & _PAGE_RW;
}

static inline int pte_file(pte_t pte)
{
        return pte_flags(pte) & _PAGE_FILE;
}

static inline int pte_huge(pte_t pte)
{
        return pte_flags(pte) & _PAGE_PSE;
}

static inline int pte_global(pte_t pte)
{
        return pte_flags(pte) & _PAGE_GLOBAL;
}

static inline int pte_exec(pte_t pte)
{
        return !(pte_flags(pte) & _PAGE_NX);
}

static inline int pte_special(pte_t pte)
{
        return pte_flags(pte) & _PAGE_SPECIAL;
}

static inline unsigned long pte_pfn(pte_t pte)
{
        return (pte_val(pte) & PTE_PFN_MASK) >> PAGE_SHIFT;
}

#define pte_page(pte)   pfn_to_page(pte_pfn(pte))

static inline int pmd_large(pmd_t pte)
{
        return (pmd_flags(pte) & (_PAGE_PSE | _PAGE_PRESENT)) ==
                (_PAGE_PSE | _PAGE_PRESENT);
}

static inline pte_t pte_mkclean(pte_t pte)
{
        return __pte(pte_val(pte) & ~_PAGE_DIRTY);
}

static inline pte_t pte_mkold(pte_t pte)
{
        return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
}

static inline pte_t pte_wrprotect(pte_t pte)
{
        return __pte(pte_val(pte) & ~_PAGE_RW);
}

static inline pte_t pte_mkexec(pte_t pte)
{
        return __pte(pte_val(pte) & ~_PAGE_NX);
}

static inline pte_t pte_mkdirty(pte_t pte)
{
        return __pte(pte_val(pte) | _PAGE_DIRTY);
}

static inline pte_t pte_mkyoung(pte_t pte)
{
        return __pte(pte_val(pte) | _PAGE_ACCESSED);
}

static inline pte_t pte_mkwrite(pte_t pte)
{
        return __pte(pte_val(pte) | _PAGE_RW);
}

static inline pte_t pte_mkhuge(pte_t pte)
{
        return __pte(pte_val(pte) | _PAGE_PSE);
}

static inline pte_t pte_clrhuge(pte_t pte)
{
        return __pte(pte_val(pte) & ~_PAGE_PSE);
}

static inline pte_t pte_mkglobal(pte_t pte)
{
        return __pte(pte_val(pte) | _PAGE_GLOBAL);
}

static inline pte_t pte_clrglobal(pte_t pte)
{
        return __pte(pte_val(pte) & ~_PAGE_GLOBAL);
}

static inline pte_t pte_mkspecial(pte_t pte)
{
        return __pte(pte_val(pte) | _PAGE_SPECIAL);
}

extern pteval_t __supported_pte_mask;

static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
{
        return __pte((((phys_addr_t)page_nr << PAGE_SHIFT) |
                      pgprot_val(pgprot)) & __supported_pte_mask);
}

static inline pmd_t pfn_pmd(unsigned long page_nr, pgprot_t pgprot)
{
        return __pmd((((phys_addr_t)page_nr << PAGE_SHIFT) |
                      pgprot_val(pgprot)) & __supported_pte_mask);
}

static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
        pteval_t val = pte_val(pte);

        /*
         * Chop off the NX bit (if present), and add the NX portion of
         * the newprot (if present):
         */
        val &= _PAGE_CHG_MASK;
        val |= pgprot_val(newprot) & (~_PAGE_CHG_MASK) & __supported_pte_mask;

        return __pte(val);
}

/* mprotect needs to preserve PAT bits when updating vm_page_prot */
#define pgprot_modify pgprot_modify
static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
{
        pgprotval_t preservebits = pgprot_val(oldprot) & _PAGE_CHG_MASK;
        pgprotval_t addbits = pgprot_val(newprot);
        return __pgprot(preservebits | addbits);
}

#define pte_pgprot(x) __pgprot(pte_flags(x) & PTE_FLAGS_MASK)

#define canon_pgprot(p) __pgprot(pgprot_val(p) & __supported_pte_mask)

static inline int is_new_memtype_allowed(unsigned long flags,
                                                unsigned long new_flags)
{
        /*
         * Certain new memtypes are not allowed with certain
         * requested memtype:
         * - request is uncached, return cannot be write-back
         * - request is write-combine, return cannot be write-back
         */
        if ((flags == _PAGE_CACHE_UC_MINUS &&
             new_flags == _PAGE_CACHE_WB) ||
            (flags == _PAGE_CACHE_WC &&
             new_flags == _PAGE_CACHE_WB)) {
                return 0;
        }

        return 1;
}

#ifndef __ASSEMBLY__
/* 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);
#endif

/* 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
static inline void native_pagetable_setup_start(pgd_t *base) {}
static inline void native_pagetable_setup_done(pgd_t *base) {}
#endif

struct seq_file;
extern void arch_report_meminfo(struct seq_file *m);

#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else  /* !CONFIG_PARAVIRT */
#define set_pte(ptep, pte)              native_set_pte(ptep, pte)
#define set_pte_at(mm, addr, ptep, pte) native_set_pte_at(mm, addr, ptep, pte)

#define set_pte_present(mm, addr, ptep, pte)                            \
        native_set_pte_present(mm, addr, ptep, pte)
#define set_pte_atomic(ptep, pte)                                       \
        native_set_pte_atomic(ptep, pte)

#define set_pmd(pmdp, pmd)              native_set_pmd(pmdp, pmd)

#ifndef __PAGETABLE_PUD_FOLDED
#define set_pgd(pgdp, pgd)              native_set_pgd(pgdp, pgd)
#define pgd_clear(pgd)                  native_pgd_clear(pgd)
#endif

#ifndef set_pud
# define set_pud(pudp, pud)             native_set_pud(pudp, pud)
#endif

#ifndef __PAGETABLE_PMD_FOLDED
#define pud_clear(pud)                  native_pud_clear(pud)
#endif

#define pte_clear(mm, addr, ptep)       native_pte_clear(mm, addr, ptep)
#define pmd_clear(pmd)                  native_pmd_clear(pmd)

#define pte_update(mm, addr, ptep)              do { } while (0)
#define pte_update_defer(mm, addr, ptep)        do { } while (0)

static inline void __init paravirt_pagetable_setup_start(pgd_t *base)
{
        native_pagetable_setup_start(base);
}

static inline void __init paravirt_pagetable_setup_done(pgd_t *base)
{
        native_pagetable_setup_done(base);
}
#endif  /* CONFIG_PARAVIRT */

#endif  /* __ASSEMBLY__ */

#ifdef CONFIG_X86_32
# include "pgtable_32.h"
#else
# include "pgtable_64.h"
#endif

#ifndef __ASSEMBLY__
#include <linux/mm_types.h>

static inline int pte_none(pte_t pte)
{
        return !pte.pte;
}

#define __HAVE_ARCH_PTE_SAME
static inline int pte_same(pte_t a, pte_t b)
{
        return a.pte == b.pte;
}

static inline int pte_present(pte_t a)
{
        return pte_flags(a) & (_PAGE_PRESENT | _PAGE_PROTNONE);
}

static inline int pmd_present(pmd_t pmd)
{
        return pmd_flags(pmd) & _PAGE_PRESENT;
}

static inline int pmd_none(pmd_t pmd)
{
        /* Only check low word on 32-bit platforms, since it might be
           out of sync with upper half. */
        return !(unsigned long)native_pmd_val(pmd);
}

static inline unsigned long pmd_page_vaddr(pmd_t pmd)
{
        return (unsigned long)__va(pmd_val(pmd) & PTE_PFN_MASK);
}

static inline struct page *pmd_page(pmd_t pmd)
{
        return pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT);
}

/*
 * 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
 */
static inline unsigned pmd_index(unsigned long address)
{
        return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}

/*
 * Conversion functions: convert a page and protection to a page entry,
 * and a page entry and page directory to the page they refer to.
 *
 * (Currently stuck as a macro because of indirect forward reference
 * to linux/mm.h:page_to_nid())
 */
#define mk_pte(page, pgprot)   pfn_pte(page_to_pfn(page), (pgprot))

/*
 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
 *
 * this function returns the index of the entry in the pte page which would
 * control the given virtual address
 */
static inline unsigned pte_index(unsigned long address)
{
        return (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
}

static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long address)
{
        return (pte_t *)pmd_page_vaddr(*pmd) + pte_index(address);
}

static inline int pmd_bad(pmd_t pmd)
{
        return (pmd_flags(pmd) & ~_PAGE_USER) != _KERNPG_TABLE;
}

static inline unsigned long pages_to_mb(unsigned long npg)
{
        return npg >> (20 - PAGE_SHIFT);
}

#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
        remap_pfn_range(vma, vaddr, pfn, size, prot)

#if PAGETABLE_LEVELS > 2
static inline int pud_none(pud_t pud)
{
        return pud_val(pud) == 0;
}

static inline int pud_present(pud_t pud)
{
        return pud_flags(pud) & _PAGE_PRESENT;
}

static inline unsigned long pud_page_vaddr(pud_t pud)
{
        return (unsigned long)__va((unsigned long)pud_val(pud) & PTE_PFN_MASK);
}

static inline struct page *pud_page(pud_t pud)
{
        return pfn_to_page(pud_val(pud) >> PAGE_SHIFT);
}

/* Find an entry in the second-level page table.. */
static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
        return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

static inline unsigned long pmd_pfn(pmd_t pmd)
{
        return (pmd_val(pmd) & PTE_PFN_MASK) >> PAGE_SHIFT;
}

static inline int pud_large(pud_t pud)
{
        return (pud_flags(pud) & (_PAGE_PSE | _PAGE_PRESENT)) ==
                (_PAGE_PSE | _PAGE_PRESENT);
}

static inline int pud_bad(pud_t pud)
{
        return (pud_flags(pud) & ~(_KERNPG_TABLE | _PAGE_USER)) != 0;
}
#endif  /* PAGETABLE_LEVELS > 2 */

#if PAGETABLE_LEVELS > 3
static inline int pgd_present(pgd_t pgd)
{
        return pgd_flags(pgd) & _PAGE_PRESENT;
}

static inline unsigned long pgd_page_vaddr(pgd_t pgd)
{
        return (unsigned long)__va((unsigned long)pgd_val(pgd) & PTE_PFN_MASK);
}

static inline struct page *pgd_page(pgd_t pgd)
{
        return pfn_to_page(pgd_val(pgd) >> PAGE_SHIFT);
}

/* to find an entry in a page-table-directory. */
static inline unsigned pud_index(unsigned long address)
{
        return (address >> PUD_SHIFT) & (PTRS_PER_PUD - 1);
}

static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
{
        return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(address);
}

static inline int pgd_bad(pgd_t pgd)
{
        return (pgd_flags(pgd) & ~_PAGE_USER) != _KERNPG_TABLE;
}

static inline int pgd_none(pgd_t pgd)
{
        return !pgd_val(pgd);
}
#endif  /* PAGETABLE_LEVELS > 3 */

#endif  /* __ASSEMBLY__ */

/*
 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
 *
 * this macro returns the index of the entry in the pgd page which would
 * control the given virtual address
 */
#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))

/*
 * pgd_offset() returns a (pgd_t *)
 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
 */
#define pgd_offset(mm, address) ((mm)->pgd + pgd_index((address)))
/*
 * a shortcut which implies the use of the kernel's pgd, instead
 * of a process's
 */
#define pgd_offset_k(address) pgd_offset(&init_mm, (address))


#define KERNEL_PGD_BOUNDARY     pgd_index(PAGE_OFFSET)
#define KERNEL_PGD_PTRS         (PTRS_PER_PGD - KERNEL_PGD_BOUNDARY)

#ifndef __ASSEMBLY__

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);

/* local pte updates need not use xchg for locking */
static inline pte_t native_local_ptep_get_and_clear(pte_t *ptep)
{
        pte_t res = *ptep;

        /* Pure native function needs no input for mm, addr */
        native_pte_clear(NULL, 0, ptep);
        return res;
}

static inline void native_set_pte_at(struct mm_struct *mm, unsigned long addr,
                                     pte_t *ptep , pte_t pte)
{
        native_set_pte(ptep, pte);
}

#ifndef CONFIG_PARAVIRT
/*
 * Rules for using pte_update - it must be called after any PTE update which
 * has not been done using the set_pte / clear_pte interfaces.  It is used by
 * shadow mode hypervisors to resynchronize the shadow page tables.  Kernel PTE
 * updates should either be sets, clears, or set_pte_atomic for P->P
 * transitions, which means this hook should only be called for user PTEs.
 * This hook implies a P->P protection or access change has taken place, which
 * requires a subsequent TLB flush.  The notification can optionally be delayed
 * until the TLB flush event by using the pte_update_defer form of the
 * interface, but care must be taken to assure that the flush happens while
 * still holding the same page table lock so that the shadow and primary pages
 * do not become out of sync on SMP.
 */
#define pte_update(mm, addr, ptep)              do { } while (0)
#define pte_update_defer(mm, addr, ptep)        do { } while (0)
#endif

/*
 * We only update the dirty/accessed state if we set
 * the dirty bit by hand in the kernel, since the hardware
 * will do the accessed bit for us, and we don't want to
 * race with other CPU's that might be updating the dirty
 * bit at the same time.
 */
struct vm_area_struct;

#define  __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
extern int ptep_set_access_flags(struct vm_area_struct *vma,
                                 unsigned long address, pte_t *ptep,
                                 pte_t entry, int dirty);

#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
extern int ptep_test_and_clear_young(struct vm_area_struct *vma,
                                     unsigned long addr, pte_t *ptep);

#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
extern int ptep_clear_flush_young(struct vm_area_struct *vma,
                                  unsigned long address, pte_t *ptep);

#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
                                       pte_t *ptep)
{
        pte_t pte = native_ptep_get_and_clear(ptep);
        pte_update(mm, addr, ptep);
        return pte;
}

#define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
                                            unsigned long addr, pte_t *ptep,
                                            int full)
{
        pte_t pte;
        if (full) {
                /*
                 * Full address destruction in progress; paravirt does not
                 * care about updates and native needs no locking
                 */
                pte = native_local_ptep_get_and_clear(ptep);
        } else {
                pte = ptep_get_and_clear(mm, addr, ptep);
        }
        return pte;
}

#define __HAVE_ARCH_PTEP_SET_WRPROTECT
static inline void ptep_set_wrprotect(struct mm_struct *mm,
                                      unsigned long addr, pte_t *ptep)
{
        clear_bit(_PAGE_BIT_RW, (unsigned long *)&ptep->pte);
        pte_update(mm, addr, ptep);
}

/*
 * clone_pgd_range(pgd_t *dst, pgd_t *src, int count);
 *
 *  dst - pointer to pgd range anwhere on a pgd page
 *  src - ""
 *  count - the number of pgds to copy.
 *
 * dst and src can be on the same page, but the range must not overlap,
 * and must not cross a page boundary.
 */
static inline void clone_pgd_range(pgd_t *dst, pgd_t *src, int count)
{
       memcpy(dst, src, count * sizeof(pgd_t));
}


#include <asm-generic/pgtable.h>
#endif  /* __ASSEMBLY__ */

#endif /* _ASM_X86_PGTABLE_H */