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#ifndef _ASM_X86_PGTABLE_2LEVEL_H
#define _ASM_X86_PGTABLE_2LEVEL_H
#define pte_ERROR(e) \
printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, (e).pte_low)
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
/*
* Certain architectures need to do special things when PTEs
* within a page table are directly modified. Thus, the following
* hook is made available.
*/
static inline void native_set_pte(pte_t *ptep , pte_t pte)
{
*ptep = pte;
}
static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
{
*pmdp = pmd;
}
static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
{
native_set_pte(ptep, pte);
}
static inline void native_pmd_clear(pmd_t *pmdp)
{
native_set_pmd(pmdp, __pmd(0));
}
static inline void native_pte_clear(struct mm_struct *mm,
unsigned long addr, pte_t *xp)
{
*xp = native_make_pte(0);
}
#ifdef CONFIG_SMP
static inline pte_t native_ptep_get_and_clear(pte_t *xp)
{
return __pte(xchg(&xp->pte_low, 0));
}
#else
#define native_ptep_get_and_clear(xp) native_local_ptep_get_and_clear(xp)
#endif
/*
* Bits _PAGE_BIT_PRESENT, _PAGE_BIT_FILE and _PAGE_BIT_PROTNONE are taken,
* split up the 29 bits of offset into this range:
*/
#define PTE_FILE_MAX_BITS 29
#define PTE_FILE_SHIFT1 (_PAGE_BIT_PRESENT + 1)
#if _PAGE_BIT_FILE < _PAGE_BIT_PROTNONE
#define PTE_FILE_SHIFT2 (_PAGE_BIT_FILE + 1)
#define PTE_FILE_SHIFT3 (_PAGE_BIT_PROTNONE + 1)
#else
#define PTE_FILE_SHIFT2 (_PAGE_BIT_PROTNONE + 1)
#define PTE_FILE_SHIFT3 (_PAGE_BIT_FILE + 1)
#endif
#define PTE_FILE_BITS1 (PTE_FILE_SHIFT2 - PTE_FILE_SHIFT1 - 1)
#define PTE_FILE_BITS2 (PTE_FILE_SHIFT3 - PTE_FILE_SHIFT2 - 1)
#define pte_to_pgoff(pte) \
((((pte).pte_low >> PTE_FILE_SHIFT1) \
& ((1U << PTE_FILE_BITS1) - 1)) \
+ ((((pte).pte_low >> PTE_FILE_SHIFT2) \
& ((1U << PTE_FILE_BITS2) - 1)) << PTE_FILE_BITS1) \
+ (((pte).pte_low >> PTE_FILE_SHIFT3) \
<< (PTE_FILE_BITS1 + PTE_FILE_BITS2)))
#define pgoff_to_pte(off) \
((pte_t) { .pte_low = \
(((off) & ((1U << PTE_FILE_BITS1) - 1)) << PTE_FILE_SHIFT1) \
+ ((((off) >> PTE_FILE_BITS1) & ((1U << PTE_FILE_BITS2) - 1)) \
<< PTE_FILE_SHIFT2) \
+ (((off) >> (PTE_FILE_BITS1 + PTE_FILE_BITS2)) \
<< PTE_FILE_SHIFT3) \
+ _PAGE_FILE })
/* Encode and de-code a swap entry */
#if _PAGE_BIT_FILE < _PAGE_BIT_PROTNONE
#define SWP_TYPE_BITS (_PAGE_BIT_FILE - _PAGE_BIT_PRESENT - 1)
#define SWP_OFFSET_SHIFT (_PAGE_BIT_PROTNONE + 1)
#else
#define SWP_TYPE_BITS (_PAGE_BIT_PROTNONE - _PAGE_BIT_PRESENT - 1)
#define SWP_OFFSET_SHIFT (_PAGE_BIT_FILE + 1)
#endif
#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
#define __swp_type(x) (((x).val >> (_PAGE_BIT_PRESENT + 1)) \
& ((1U << SWP_TYPE_BITS) - 1))
#define __swp_offset(x) ((x).val >> SWP_OFFSET_SHIFT)
#define __swp_entry(type, offset) ((swp_entry_t) { \
((type) << (_PAGE_BIT_PRESENT + 1)) \
| ((offset) << SWP_OFFSET_SHIFT) })
#define __pte_to_swp_entry(pte) ((swp_entry_t) { (pte).pte_low })
#define __swp_entry_to_pte(x) ((pte_t) { .pte = (x).val })
#endif /* _ASM_X86_PGTABLE_2LEVEL_H */
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