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

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _PGTABLE_NOPUD_H
   3#define _PGTABLE_NOPUD_H
   4
   5#ifndef __ASSEMBLY__
   6
   7#include <asm-generic/pgtable-nop4d.h>
   8
   9#define __PAGETABLE_PUD_FOLDED 1
  10
  11/*
  12 * Having the pud type consist of a p4d gets the size right, and allows
  13 * us to conceptually access the p4d entry that this pud is folded into
  14 * without casting.
  15 */
  16typedef struct { p4d_t p4d; } pud_t;
  17
  18#define PUD_SHIFT       P4D_SHIFT
  19#define PTRS_PER_PUD    1
  20#define PUD_SIZE        (1UL << PUD_SHIFT)
  21#define PUD_MASK        (~(PUD_SIZE-1))
  22
  23/*
  24 * The "p4d_xxx()" functions here are trivial for a folded two-level
  25 * setup: the pud is never bad, and a pud always exists (as it's folded
  26 * into the p4d entry)
  27 */
  28static inline int p4d_none(p4d_t p4d)           { return 0; }
  29static inline int p4d_bad(p4d_t p4d)            { return 0; }
  30static inline int p4d_present(p4d_t p4d)        { return 1; }
  31static inline void p4d_clear(p4d_t *p4d)        { }
  32#define pud_ERROR(pud)                          (p4d_ERROR((pud).p4d))
  33
  34#define p4d_populate(mm, p4d, pud)              do { } while (0)
  35#define p4d_populate_safe(mm, p4d, pud)         do { } while (0)
  36/*
  37 * (puds are folded into p4ds so this doesn't get actually called,
  38 * but the define is needed for a generic inline function.)
  39 */
  40#define set_p4d(p4dptr, p4dval) set_pud((pud_t *)(p4dptr), (pud_t) { p4dval })
  41
  42static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
  43{
  44        return (pud_t *)p4d;
  45}
  46#define pud_offset pud_offset
  47
  48#define pud_val(x)                              (p4d_val((x).p4d))
  49#define __pud(x)                                ((pud_t) { __p4d(x) })
  50
  51#define p4d_page(p4d)                           (pud_page((pud_t){ p4d }))
  52#define p4d_pgtable(p4d)                        ((pud_t *)(pud_pgtable((pud_t){ p4d })))
  53
  54/*
  55 * allocating and freeing a pud is trivial: the 1-entry pud is
  56 * inside the p4d, so has no extra memory associated with it.
  57 */
  58#define pud_alloc_one(mm, address)              NULL
  59#define pud_free(mm, x)                         do { } while (0)
  60#define pud_free_tlb(tlb, x, a)                 do { } while (0)
  61
  62#undef  pud_addr_end
  63#define pud_addr_end(addr, end)                 (end)
  64
  65#endif /* __ASSEMBLY__ */
  66#endif /* _PGTABLE_NOPUD_H */
  67