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