include/asm-generic/pgtable-nopmd.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _PGTABLE_NOPMD_H
   3 #define _PGTABLE_NOPMD_H
   4
   5 #ifndef __ASSEMBLY__
   6
   7 #include <asm-generic/pgtable-nopud.h>
   8
   9 struct mm_struct;
  10
  11 #define __PAGETABLE_PMD_FOLDED 1
  12
  13 /*
  14  * Having the pmd type consist of a pud gets the size right, and allows
  15  * us to conceptually access the pud entry that this pmd is folded into
  16  * without casting.
  17  */
  18 typedef struct { pud_t pud; } pmd_t;
  19
  20 #define PMD_SHIFT       PUD_SHIFT
  21 #define PTRS_PER_PMD    1
  22 #define PMD_SIZE        (1UL << PMD_SHIFT)
  23 #define PMD_MASK        (~(PMD_SIZE-1))
  24
  25 /*
  26  * The "pud_xxx()" functions here are trivial for a folded two-level
  27  * setup: the pmd is never bad, and a pmd always exists (as it's folded
  28  * into the pud entry)
  29  */
  30 static inline int pud_none(pud_t pud)           { return 0; }
  31 static inline int pud_bad(pud_t pud)            { return 0; }
  32 static inline int pud_present(pud_t pud)        { return 1; }
  33 static inline void pud_clear(pud_t *pud)        { }
  34 #define pmd_ERROR(pmd)                          (pud_ERROR((pmd).pud))
  35
  36 #define pud_populate(mm, pmd, pte)              do { } while (0)
  37
  38 /*
  39  * (pmds are folded into puds so this doesn't get actually called,
  40  * but the define is needed for a generic inline function.)
  41  */
  42 #define set_pud(pudptr, pudval)                 set_pmd((pmd_t *)(pudptr), (pmd_t) { pudval })
  43
  44 static inline pmd_t * pmd_offset(pud_t * pud, unsigned long address)
  45 {
  46         return (pmd_t *)pud;
  47 }
  48
  49 #define pmd_val(x)                              (pud_val((x).pud))
  50 #define __pmd(x)                                ((pmd_t) { __pud(x) } )
  51
  52 #define pud_page(pud)                           (pmd_page((pmd_t){ pud }))
  53 #define pud_page_vaddr(pud)                     (pmd_page_vaddr((pmd_t){ pud }))
  54
  55 /*
  56  * allocating and freeing a pmd is trivial: the 1-entry pmd is
  57  * inside the pud, so has no extra memory associated with it.
  58  */
  59 #define pmd_alloc_one(mm, address)              NULL
  60 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
  61 {
  62 }
  63 #define __pmd_free_tlb(tlb, x, a)               do { } while (0)
  64
  65 #undef  pmd_addr_end
  66 #define pmd_addr_end(addr, end)                 (end)
  67
  68 #endif /* __ASSEMBLY__ */
  69
  70 #endif /* _PGTABLE_NOPMD_H */