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#ifndef _I386_PGTABLE_2LEVEL_H
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#define _I386_PGTABLE_2LEVEL_H
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/*
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 * traditional i386 two-level paging structure:
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 */
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#define PGDIR_SHIFT     22
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#define PTRS_PER_PGD    1024
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/*
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 * the i386 is two-level, so we don't really have any
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 * PMD directory physically.
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 */
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#define PMD_SHIFT       22
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#define PTRS_PER_PMD    1
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#define PTRS_PER_PTE    1024
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#define pte_ERROR(e) \
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        printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, (e).pte_low)
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#define pmd_ERROR(e) \
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        printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
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#define pgd_ERROR(e) \
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        printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
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/*
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 * The "pgd_xxx()" functions here are trivial for a folded two-level
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 * setup: the pgd is never bad, and a pmd always exists (as it's folded
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 * into the pgd entry)
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 */
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static inline int pgd_none(pgd_t pgd)           { return 0; }
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static inline int pgd_bad(pgd_t pgd)            { return 0; }
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static inline int pgd_present(pgd_t pgd)        { return 1; }
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#define pgd_clear(xp)                           do { } while (0)
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/*
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 * Certain architectures need to do special things when PTEs
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 * within a page table are directly modified.  Thus, the following
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 * hook is made available.
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 */
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#define set_pte(pteptr, pteval) (*(pteptr) = pteval)
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#define set_pte_atomic(pteptr, pteval) set_pte(pteptr,pteval)
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/*
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 * (pmds are folded into pgds so this doesn't get actually called,
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 * but the define is needed for a generic inline function.)
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 */
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#define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
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#define set_pgd(pgdptr, pgdval) (*(pgdptr) = pgdval)
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#define pgd_page(pgd) \
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((unsigned long) __va(pgd_val(pgd) & PAGE_MASK))
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static inline pmd_t * pmd_offset(pgd_t * dir, unsigned long address)
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{
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        return (pmd_t *) dir;
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}
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#define ptep_get_and_clear(xp)  __pte(xchg(&(xp)->pte_low, 0))
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#define pte_same(a, b)          ((a).pte_low == (b).pte_low)
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#define pte_page(x)             pfn_to_page(pte_pfn(x))
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#define pte_none(x)             (!(x).pte_low)
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#define pte_pfn(x)              ((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
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#define pfn_pte(pfn, prot)      __pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
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#define pfn_pmd(pfn, prot)      __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
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/*
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 * Bits 0, 6 and 7 are taken, split up the 29 bits of offset
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 * into this range:
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 */
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#define PTE_FILE_MAX_BITS       29
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#define pte_to_pgoff(pte) \
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        ((((pte).pte_low >> 1) & 0x1f ) + (((pte).pte_low >> 8) << 5 ))
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#define pgoff_to_pte(off) \
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        ((pte_t) { (((off) & 0x1f) << 1) + (((off) >> 5) << 8) + _PAGE_FILE })
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#endif /* _I386_PGTABLE_2LEVEL_H */