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

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