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-rw-r--r--arch/x86/include/asm/pgtable-3level.h175
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diff --git a/arch/x86/include/asm/pgtable-3level.h b/arch/x86/include/asm/pgtable-3level.h
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1#ifndef _ASM_X86_PGTABLE_3LEVEL_H
2#define _ASM_X86_PGTABLE_3LEVEL_H
3
4/*
5 * Intel Physical Address Extension (PAE) Mode - three-level page
6 * tables on PPro+ CPUs.
7 *
8 * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
9 */
10
11#define pte_ERROR(e) \
12 printk("%s:%d: bad pte %p(%08lx%08lx).\n", \
13 __FILE__, __LINE__, &(e), (e).pte_high, (e).pte_low)
14#define pmd_ERROR(e) \
15 printk("%s:%d: bad pmd %p(%016Lx).\n", \
16 __FILE__, __LINE__, &(e), pmd_val(e))
17#define pgd_ERROR(e) \
18 printk("%s:%d: bad pgd %p(%016Lx).\n", \
19 __FILE__, __LINE__, &(e), pgd_val(e))
20
21static inline int pud_none(pud_t pud)
22{
23 return pud_val(pud) == 0;
24}
25
26static inline int pud_bad(pud_t pud)
27{
28 return (pud_val(pud) & ~(PTE_PFN_MASK | _KERNPG_TABLE | _PAGE_USER)) != 0;
29}
30
31static inline int pud_present(pud_t pud)
32{
33 return pud_val(pud) & _PAGE_PRESENT;
34}
35
36/* Rules for using set_pte: the pte being assigned *must* be
37 * either not present or in a state where the hardware will
38 * not attempt to update the pte. In places where this is
39 * not possible, use pte_get_and_clear to obtain the old pte
40 * value and then use set_pte to update it. -ben
41 */
42static inline void native_set_pte(pte_t *ptep, pte_t pte)
43{
44 ptep->pte_high = pte.pte_high;
45 smp_wmb();
46 ptep->pte_low = pte.pte_low;
47}
48
49/*
50 * Since this is only called on user PTEs, and the page fault handler
51 * must handle the already racy situation of simultaneous page faults,
52 * we are justified in merely clearing the PTE present bit, followed
53 * by a set. The ordering here is important.
54 */
55static inline void native_set_pte_present(struct mm_struct *mm,
56 unsigned long addr,
57 pte_t *ptep, pte_t pte)
58{
59 ptep->pte_low = 0;
60 smp_wmb();
61 ptep->pte_high = pte.pte_high;
62 smp_wmb();
63 ptep->pte_low = pte.pte_low;
64}
65
66static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
67{
68 set_64bit((unsigned long long *)(ptep), native_pte_val(pte));
69}
70
71static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
72{
73 set_64bit((unsigned long long *)(pmdp), native_pmd_val(pmd));
74}
75
76static inline void native_set_pud(pud_t *pudp, pud_t pud)
77{
78 set_64bit((unsigned long long *)(pudp), native_pud_val(pud));
79}
80
81/*
82 * For PTEs and PDEs, we must clear the P-bit first when clearing a page table
83 * entry, so clear the bottom half first and enforce ordering with a compiler
84 * barrier.
85 */
86static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
87 pte_t *ptep)
88{
89 ptep->pte_low = 0;
90 smp_wmb();
91 ptep->pte_high = 0;
92}
93
94static inline void native_pmd_clear(pmd_t *pmd)
95{
96 u32 *tmp = (u32 *)pmd;
97 *tmp = 0;
98 smp_wmb();
99 *(tmp + 1) = 0;
100}
101
102static inline void pud_clear(pud_t *pudp)
103{
104 unsigned long pgd;
105
106 set_pud(pudp, __pud(0));
107
108 /*
109 * According to Intel App note "TLBs, Paging-Structure Caches,
110 * and Their Invalidation", April 2007, document 317080-001,
111 * section 8.1: in PAE mode we explicitly have to flush the
112 * TLB via cr3 if the top-level pgd is changed...
113 *
114 * Make sure the pud entry we're updating is within the
115 * current pgd to avoid unnecessary TLB flushes.
116 */
117 pgd = read_cr3();
118 if (__pa(pudp) >= pgd && __pa(pudp) <
119 (pgd + sizeof(pgd_t)*PTRS_PER_PGD))
120 write_cr3(pgd);
121}
122
123#define pud_page(pud) ((struct page *) __va(pud_val(pud) & PTE_PFN_MASK))
124
125#define pud_page_vaddr(pud) ((unsigned long) __va(pud_val(pud) & PTE_PFN_MASK))
126
127
128/* Find an entry in the second-level page table.. */
129#define pmd_offset(pud, address) ((pmd_t *)pud_page(*(pud)) + \
130 pmd_index(address))
131
132#ifdef CONFIG_SMP
133static inline pte_t native_ptep_get_and_clear(pte_t *ptep)
134{
135 pte_t res;
136
137 /* xchg acts as a barrier before the setting of the high bits */
138 res.pte_low = xchg(&ptep->pte_low, 0);
139 res.pte_high = ptep->pte_high;
140 ptep->pte_high = 0;
141
142 return res;
143}
144#else
145#define native_ptep_get_and_clear(xp) native_local_ptep_get_and_clear(xp)
146#endif
147
148#define __HAVE_ARCH_PTE_SAME
149static inline int pte_same(pte_t a, pte_t b)
150{
151 return a.pte_low == b.pte_low && a.pte_high == b.pte_high;
152}
153
154static inline int pte_none(pte_t pte)
155{
156 return !pte.pte_low && !pte.pte_high;
157}
158
159/*
160 * Bits 0, 6 and 7 are taken in the low part of the pte,
161 * put the 32 bits of offset into the high part.
162 */
163#define pte_to_pgoff(pte) ((pte).pte_high)
164#define pgoff_to_pte(off) \
165 ((pte_t) { { .pte_low = _PAGE_FILE, .pte_high = (off) } })
166#define PTE_FILE_MAX_BITS 32
167
168/* Encode and de-code a swap entry */
169#define __swp_type(x) (((x).val) & 0x1f)
170#define __swp_offset(x) ((x).val >> 5)
171#define __swp_entry(type, offset) ((swp_entry_t){(type) | (offset) << 5})
172#define __pte_to_swp_entry(pte) ((swp_entry_t){ (pte).pte_high })
173#define __swp_entry_to_pte(x) ((pte_t){ { .pte_high = (x).val } })
174
175#endif /* _ASM_X86_PGTABLE_3LEVEL_H */