pgtable-3level.h

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/*
 * Copyright 2003 PathScale Inc
 * Derived from include/asm-i386/pgtable.h
 * Licensed under the GPL
 */

#ifndef __UM_PGTABLE_3LEVEL_H
#define __UM_PGTABLE_3LEVEL_H

#include <asm-generic/pgtable-nopud.h>

/* PGDIR_SHIFT determines what a third-level page table entry can map */

#ifdef CONFIG_64BIT
#define PGDIR_SHIFT 30
#else
#define PGDIR_SHIFT 31
#endif
#define PGDIR_SIZE  (1UL << PGDIR_SHIFT)
#define PGDIR_MASK  (~(PGDIR_SIZE-1))

/* PMD_SHIFT determines the size of the area a second-level page table can
 * map
 */

#define PMD_SHIFT   21
#define PMD_SIZE    (1UL << PMD_SHIFT)
#define PMD_MASK    (~(PMD_SIZE-1))

/*
 * entries per page directory level
 */

#define PTRS_PER_PTE 512
#ifdef CONFIG_64BIT
#define PTRS_PER_PMD 512
#define PTRS_PER_PGD 512
#else
#define PTRS_PER_PMD 1024
#define PTRS_PER_PGD 1024
#endif

#define USER_PTRS_PER_PGD ((TASK_SIZE + (PGDIR_SIZE - 1)) / PGDIR_SIZE)
#define FIRST_USER_ADDRESS  0

#define pte_ERROR(e) \
        printk("%s:%d: bad pte %p(%016lx).\n", __FILE__, __LINE__, &(e), \
           pte_val(e))
#define pmd_ERROR(e) \
        printk("%s:%d: bad pmd %p(%016lx).\n", __FILE__, __LINE__, &(e), \
           pmd_val(e))
#define pgd_ERROR(e) \
        printk("%s:%d: bad pgd %p(%016lx).\n", __FILE__, __LINE__, &(e), \
           pgd_val(e))

#define pud_none(x) (!(pud_val(x) & ~_PAGE_NEWPAGE))
#define pud_bad(x)  ((pud_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
#define pud_present(x)  (pud_val(x) & _PAGE_PRESENT)
#define pud_populate(mm, pud, pmd) \
    set_pud(pud, __pud(_PAGE_TABLE + __pa(pmd)))

#ifdef CONFIG_64BIT
#define set_pud(pudptr, pudval) set_64bit((u64 *) (pudptr), pud_val(pudval))
#else
#define set_pud(pudptr, pudval) (*(pudptr) = (pudval))
#endif

static inline int pgd_newpage(pgd_t pgd)
{
    return(pgd_val(pgd) & _PAGE_NEWPAGE);
}

static inline void pgd_mkuptodate(pgd_t pgd) { pgd_val(pgd) &= ~_PAGE_NEWPAGE; }

#ifdef CONFIG_64BIT
#define set_pmd(pmdptr, pmdval) set_64bit((u64 *) (pmdptr), pmd_val(pmdval))
#else
#define set_pmd(pmdptr, pmdval) (*(pmdptr) = (pmdval))
#endif

struct mm_struct;
extern pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address);

static inline void pud_clear (pud_t *pud)
{
    set_pud(pud, __pud(_PAGE_NEWPAGE));
}

#define pud_page(pud) phys_to_page(pud_val(pud) & PAGE_MASK)
#define pud_page_vaddr(pud) ((unsigned long) __va(pud_val(pud) & PAGE_MASK))

/* Find an entry in the second-level page table.. */
#define pmd_offset(pud, address) ((pmd_t *) pud_page_vaddr(*(pud)) + \
            pmd_index(address))

static inline unsigned long pte_pfn(pte_t pte)
{
    return phys_to_pfn(pte_val(pte));
}

static inline pte_t pfn_pte(pfn_t page_nr, pgprot_t pgprot)
{
    pte_t pte;
    phys_t phys = pfn_to_phys(page_nr);

    pte_set_val(pte, phys, pgprot);
    return pte;
}

static inline pmd_t pfn_pmd(pfn_t page_nr, pgprot_t pgprot)
{
    return __pmd((page_nr << PAGE_SHIFT) | pgprot_val(pgprot));
}

/*
 * Bits 0 through 3 are taken in the low part of the pte,
 * put the 32 bits of offset into the high part.
 */
#define PTE_FILE_MAX_BITS   32

#ifdef CONFIG_64BIT

#define pte_to_pgoff(p) ((p).pte >> 32)

#define pgoff_to_pte(off) ((pte_t) { ((off) << 32) | _PAGE_FILE })

#else

#define pte_to_pgoff(pte) ((pte).pte_high)

#define pgoff_to_pte(off) ((pte_t) { _PAGE_FILE, (off) })

#endif

#endif