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#ifdef __ARCH_USE_5LEVEL_HACK
   8#include <asm-generic/pgtable-nop4d-hack.h>
   9#else
  10#include <asm-generic/pgtable-nop4d.h>
  11
  12#define __PAGETABLE_PUD_FOLDED 1
  13
  14/*
  15 * Having the pud type consist of a p4d gets the size right, and allows
  16 * us to conceptually access the p4d entry that this pud is folded into
  17 * without casting.
  18 */
  19typedef struct { p4d_t p4d; } pud_t;
  20
  21#define PUD_SHIFT       P4D_SHIFT
  22#define PTRS_PER_PUD    1
  23#define PUD_SIZE        (1UL << PUD_SHIFT)
  24#define PUD_MASK        (~(PUD_SIZE-1))
  25
  26/*
  27 * The "p4d_xxx()" functions here are trivial for a folded two-level
  28 * setup: the pud is never bad, and a pud always exists (as it's folded
  29 * into the p4d entry)
  30 */
  31static inline int p4d_none(p4d_t p4d)           { return 0; }
  32static inline int p4d_bad(p4d_t p4d)            { return 0; }
  33static inline int p4d_present(p4d_t p4d)        { return 1; }
  34static inline void p4d_clear(p4d_t *p4d)        { }
  35#define pud_ERROR(pud)                          (p4d_ERROR((pud).p4d))
  36
  37#define p4d_populate(mm, p4d, pud)              do { } while (0)
  38#define p4d_populate_safe(mm, p4d, pud)         do { } while (0)
  39/*
  40 * (puds are folded into p4ds so this doesn't get actually called,
  41 * but the define is needed for a generic inline function.)
  42 */
  43#define set_p4d(p4dptr, p4dval) set_pud((pud_t *)(p4dptr), (pud_t) { p4dval })
  44
  45static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
  46{
  47        return (pud_t *)p4d;
  48}
  49
  50#define pud_val(x)                              (p4d_val((x).p4d))
  51#define __pud(x)                                ((pud_t) { __p4d(x) })
  52
  53#define p4d_page(p4d)                           (pud_page((pud_t){ p4d }))
  54#define p4d_page_vaddr(p4d)                     (pud_page_vaddr((pud_t){ p4d }))
  55
  56/*
  57 * allocating and freeing a pud is trivial: the 1-entry pud is
  58 * inside the p4d, so has no extra memory associated with it.
  59 */
  60#define pud_alloc_one(mm, address)              NULL
  61#define pud_free(mm, x)                         do { } while (0)
  62#define __pud_free_tlb(tlb, x, a)               do { } while (0)
  63
  64#undef  pud_addr_end
  65#define pud_addr_end(addr, end)                 (end)
  66
  67#endif /* __ASSEMBLY__ */
  68#endif /* !__ARCH_USE_5LEVEL_HACK */
  69#endif /* _PGTABLE_NOPUD_H */
  70