arch/x86/include/asm/pgtable-2level.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_PGTABLE_2LEVEL_H
   3 #define _ASM_X86_PGTABLE_2LEVEL_H
   4
   5 #define pte_ERROR(e) \
   6         pr_err("%s:%d: bad pte %08lx\n", __FILE__, __LINE__, (e).pte_low)
   7 #define pgd_ERROR(e) \
   8         pr_err("%s:%d: bad pgd %08lx\n", __FILE__, __LINE__, pgd_val(e))
   9
  10 /*
  11  * Certain architectures need to do special things when PTEs
  12  * within a page table are directly modified.  Thus, the following
  13  * hook is made available.
  14  */
  15 static inline void native_set_pte(pte_t *ptep , pte_t pte)
  16 {
  17         *ptep = pte;
  18 }
  19
  20 static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
  21 {
  22         *pmdp = pmd;
  23 }
  24
  25 static inline void native_set_pud(pud_t *pudp, pud_t pud)
  26 {
  27 }
  28
  29 static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
  30 {
  31         native_set_pte(ptep, pte);
  32 }
  33
  34 static inline void native_pmd_clear(pmd_t *pmdp)
  35 {
  36         native_set_pmd(pmdp, __pmd(0));
  37 }
  38
  39 static inline void native_pud_clear(pud_t *pudp)
  40 {
  41 }
  42
  43 static inline void native_pte_clear(struct mm_struct *mm,
  44                                     unsigned long addr, pte_t *xp)
  45 {
  46         *xp = native_make_pte(0);
  47 }
  48
  49 #ifdef CONFIG_SMP
  50 static inline pte_t native_ptep_get_and_clear(pte_t *xp)
  51 {
  52         return __pte(xchg(&xp->pte_low, 0));
  53 }
  54 #else
  55 #define native_ptep_get_and_clear(xp) native_local_ptep_get_and_clear(xp)
  56 #endif
  57
  58 #ifdef CONFIG_SMP
  59 static inline pmd_t native_pmdp_get_and_clear(pmd_t *xp)
  60 {
  61         return __pmd(xchg((pmdval_t *)xp, 0));
  62 }
  63 #else
  64 #define native_pmdp_get_and_clear(xp) native_local_pmdp_get_and_clear(xp)
  65 #endif
  66
  67 #ifdef CONFIG_SMP
  68 static inline pud_t native_pudp_get_and_clear(pud_t *xp)
  69 {
  70         return __pud(xchg((pudval_t *)xp, 0));
  71 }
  72 #else
  73 #define native_pudp_get_and_clear(xp) native_local_pudp_get_and_clear(xp)
  74 #endif
  75
  76 /* Bit manipulation helper on pte/pgoff entry */
  77 static inline unsigned long pte_bitop(unsigned long value, unsigned int rightshift,
  78                                       unsigned long mask, unsigned int leftshift)
  79 {
  80         return ((value >> rightshift) & mask) << leftshift;
  81 }
  82
  83 /* Encode and de-code a swap entry */
  84 #define SWP_TYPE_BITS 5
  85 #define SWP_OFFSET_SHIFT (_PAGE_BIT_PROTNONE + 1)
  86
  87 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
  88
  89 #define __swp_type(x)                   (((x).val >> (_PAGE_BIT_PRESENT + 1)) \
  90                                          & ((1U << SWP_TYPE_BITS) - 1))
  91 #define __swp_offset(x)                 ((x).val >> SWP_OFFSET_SHIFT)
  92 #define __swp_entry(type, offset)       ((swp_entry_t) { \
  93                                          ((type) << (_PAGE_BIT_PRESENT + 1)) \
  94                                          | ((offset) << SWP_OFFSET_SHIFT) })
  95 #define __pte_to_swp_entry(pte)         ((swp_entry_t) { (pte).pte_low })
  96 #define __swp_entry_to_pte(x)           ((pte_t) { .pte = (x).val })
  97
  98 #endif /* _ASM_X86_PGTABLE_2LEVEL_H */