LXR linux/include/asm-generic/pgtable-nopud.h

   1#ifndef _PGTABLE_NOPUD_H
   2#define _PGTABLE_NOPUD_H
   3
   4#ifndef __ASSEMBLY__
   5
   6#define __PAGETABLE_PUD_FOLDED
   7
   8/*
   9 * Having the pud type consist of a pgd gets the size right, and allows
  10 * us to conceptually access the pgd entry that this pud is folded into
  11 * without casting.
  12 */
  13typedef struct { pgd_t pgd; } pud_t;
  14
  15#define PUD_SHIFT       PGDIR_SHIFT
  16#define PTRS_PER_PUD    1
  17#define PUD_SIZE        (1UL << PUD_SHIFT)
  18#define PUD_MASK        (~(PUD_SIZE-1))
  19
  20/*
  21 * The "pgd_xxx()" functions here are trivial for a folded two-level
  22 * setup: the pud is never bad, and a pud always exists (as it's folded
  23 * into the pgd entry)
  24 */
  25static inline int pgd_none(pgd_t pgd)           { return 0; }
  26static inline int pgd_bad(pgd_t pgd)            { return 0; }
  27static inline int pgd_present(pgd_t pgd)        { return 1; }
  28static inline void pgd_clear(pgd_t *pgd)        { }
  29#define pud_ERROR(pud)                          (pgd_ERROR((pud).pgd))
  30
  31#define pgd_populate(mm, pgd, pud)              do { } while (0)
  32/*
  33 * (puds are folded into pgds so this doesn't get actually called,
  34 * but the define is needed for a generic inline function.)
  35 */
  36#define set_pgd(pgdptr, pgdval)                 set_pud((pud_t *)(pgdptr), (pud_t) { pgdval })
  37
  38static inline pud_t * pud_offset(pgd_t * pgd, unsigned long address)
  39{
  40        return (pud_t *)pgd;
  41}
  42
  43#define pud_val(x)                              (pgd_val((x).pgd))
  44#define __pud(x)                                ((pud_t) { __pgd(x) } )
  45
  46#define pgd_page(pgd)                           (pud_page((pud_t){ pgd }))
  47#define pgd_page_vaddr(pgd)                     (pud_page_vaddr((pud_t){ pgd }))
  48
  49/*
  50 * allocating and freeing a pud is trivial: the 1-entry pud is
  51 * inside the pgd, so has no extra memory associated with it.
  52 */
  53#define pud_alloc_one(mm, address)              NULL
  54#define pud_free(mm, x)                         do { } while (0)
  55#define __pud_free_tlb(tlb, x, a)               do { } while (0)
  56
  57#undef  pud_addr_end
  58#define pud_addr_end(addr, end)                 (end)
  59
  60#endif /* __ASSEMBLY__ */
  61#endif /* _PGTABLE_NOPUD_H */
  62