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  */
  19 typedef 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  */
  31 static inline int p4d_none(p4d_t p4d)           { return 0; }
  32 static inline int p4d_bad(p4d_t p4d)            { return 0; }
  33 static inline int p4d_present(p4d_t p4d)        { return 1; }
  34 static 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
  45 static 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 */