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  */
14 static inline void native_set_pte(pte_t *ptep , pte_t pte)
15 {
16 	*ptep = pte;
17 }
18 
19 static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
20 {
21 	*pmdp = pmd;
22 }
23 
24 static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
25 {
26 	native_set_pte(ptep, pte);
27 }
28 
29 static inline void native_pmd_clear(pmd_t *pmdp)
30 {
31 	native_set_pmd(pmdp, __pmd(0));
32 }
33 
34 static 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
41 static 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
50 static 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 */
59 static 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