xref: /linux/arch/x86/include/asm/pgtable-2level.h (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
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_pud(pud_t *pudp, pud_t pud)
25 {
26 }
27 
28 static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
29 {
30 	native_set_pte(ptep, pte);
31 }
32 
33 static inline void native_pmd_clear(pmd_t *pmdp)
34 {
35 	native_set_pmd(pmdp, __pmd(0));
36 }
37 
38 static inline void native_pud_clear(pud_t *pudp)
39 {
40 }
41 
42 static inline void native_pte_clear(struct mm_struct *mm,
43 				    unsigned long addr, pte_t *xp)
44 {
45 	*xp = native_make_pte(0);
46 }
47 
48 #ifdef CONFIG_SMP
49 static inline pte_t native_ptep_get_and_clear(pte_t *xp)
50 {
51 	return __pte(xchg(&xp->pte_low, 0));
52 }
53 #else
54 #define native_ptep_get_and_clear(xp) native_local_ptep_get_and_clear(xp)
55 #endif
56 
57 #ifdef CONFIG_SMP
58 static inline pmd_t native_pmdp_get_and_clear(pmd_t *xp)
59 {
60 	return __pmd(xchg((pmdval_t *)xp, 0));
61 }
62 #else
63 #define native_pmdp_get_and_clear(xp) native_local_pmdp_get_and_clear(xp)
64 #endif
65 
66 #ifdef CONFIG_SMP
67 static inline pud_t native_pudp_get_and_clear(pud_t *xp)
68 {
69 	return __pud(xchg((pudval_t *)xp, 0));
70 }
71 #else
72 #define native_pudp_get_and_clear(xp) native_local_pudp_get_and_clear(xp)
73 #endif
74 
75 /* Bit manipulation helper on pte/pgoff entry */
76 static inline unsigned long pte_bitop(unsigned long value, unsigned int rightshift,
77 				      unsigned long mask, unsigned int leftshift)
78 {
79 	return ((value >> rightshift) & mask) << leftshift;
80 }
81 
82 /* Encode and de-code a swap entry */
83 #define SWP_TYPE_BITS 5
84 #define SWP_OFFSET_SHIFT (_PAGE_BIT_PROTNONE + 1)
85 
86 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
87 
88 #define __swp_type(x)			(((x).val >> (_PAGE_BIT_PRESENT + 1)) \
89 					 & ((1U << SWP_TYPE_BITS) - 1))
90 #define __swp_offset(x)			((x).val >> SWP_OFFSET_SHIFT)
91 #define __swp_entry(type, offset)	((swp_entry_t) { \
92 					 ((type) << (_PAGE_BIT_PRESENT + 1)) \
93 					 | ((offset) << SWP_OFFSET_SHIFT) })
94 #define __pte_to_swp_entry(pte)		((swp_entry_t) { (pte).pte_low })
95 #define __swp_entry_to_pte(x)		((pte_t) { .pte = (x).val })
96 
97 #endif /* _ASM_X86_PGTABLE_2LEVEL_H */
98