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