Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
[pandora-kernel.git] / include / linux / huge_mm.h
1 #ifndef _LINUX_HUGE_MM_H
2 #define _LINUX_HUGE_MM_H
3
4 extern int do_huge_pmd_anonymous_page(struct mm_struct *mm,
5                                       struct vm_area_struct *vma,
6                                       unsigned long address, pmd_t *pmd,
7                                       unsigned int flags);
8 extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
9                          pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
10                          struct vm_area_struct *vma);
11 extern int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
12                                unsigned long address, pmd_t *pmd,
13                                pmd_t orig_pmd);
14 extern pgtable_t get_pmd_huge_pte(struct mm_struct *mm);
15 extern struct page *follow_trans_huge_pmd(struct mm_struct *mm,
16                                           unsigned long addr,
17                                           pmd_t *pmd,
18                                           unsigned int flags);
19 extern int zap_huge_pmd(struct mmu_gather *tlb,
20                         struct vm_area_struct *vma,
21                         pmd_t *pmd);
22 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
23                         unsigned long addr, unsigned long end,
24                         unsigned char *vec);
25 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
26                         unsigned long addr, pgprot_t newprot);
27
28 enum transparent_hugepage_flag {
29         TRANSPARENT_HUGEPAGE_FLAG,
30         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
31         TRANSPARENT_HUGEPAGE_DEFRAG_FLAG,
32         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
33         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
34 #ifdef CONFIG_DEBUG_VM
35         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
36 #endif
37 };
38
39 enum page_check_address_pmd_flag {
40         PAGE_CHECK_ADDRESS_PMD_FLAG,
41         PAGE_CHECK_ADDRESS_PMD_NOTSPLITTING_FLAG,
42         PAGE_CHECK_ADDRESS_PMD_SPLITTING_FLAG,
43 };
44 extern pmd_t *page_check_address_pmd(struct page *page,
45                                      struct mm_struct *mm,
46                                      unsigned long address,
47                                      enum page_check_address_pmd_flag flag);
48
49 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
50 #define HPAGE_PMD_SHIFT HPAGE_SHIFT
51 #define HPAGE_PMD_MASK HPAGE_MASK
52 #define HPAGE_PMD_SIZE HPAGE_SIZE
53
54 #define transparent_hugepage_enabled(__vma)                             \
55         ((transparent_hugepage_flags &                                  \
56           (1<<TRANSPARENT_HUGEPAGE_FLAG) ||                             \
57           (transparent_hugepage_flags &                                 \
58            (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                   \
59            ((__vma)->vm_flags & VM_HUGEPAGE))) &&                       \
60          !((__vma)->vm_flags & VM_NOHUGEPAGE) &&                        \
61          !is_vma_temporary_stack(__vma))
62 #define transparent_hugepage_defrag(__vma)                              \
63         ((transparent_hugepage_flags &                                  \
64           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) ||                     \
65          (transparent_hugepage_flags &                                  \
66           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) &&             \
67           (__vma)->vm_flags & VM_HUGEPAGE))
68 #ifdef CONFIG_DEBUG_VM
69 #define transparent_hugepage_debug_cow()                                \
70         (transparent_hugepage_flags &                                   \
71          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
72 #else /* CONFIG_DEBUG_VM */
73 #define transparent_hugepage_debug_cow() 0
74 #endif /* CONFIG_DEBUG_VM */
75
76 extern unsigned long transparent_hugepage_flags;
77 extern int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
78                           pmd_t *dst_pmd, pmd_t *src_pmd,
79                           struct vm_area_struct *vma,
80                           unsigned long addr, unsigned long end);
81 extern int handle_pte_fault(struct mm_struct *mm,
82                             struct vm_area_struct *vma, unsigned long address,
83                             pte_t *pte, pmd_t *pmd, unsigned int flags);
84 extern int split_huge_page(struct page *page);
85 extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);
86 #define split_huge_page_pmd(__mm, __pmd)                                \
87         do {                                                            \
88                 pmd_t *____pmd = (__pmd);                               \
89                 if (unlikely(pmd_trans_huge(*____pmd)))                 \
90                         __split_huge_page_pmd(__mm, ____pmd);           \
91         }  while (0)
92 #define wait_split_huge_page(__anon_vma, __pmd)                         \
93         do {                                                            \
94                 pmd_t *____pmd = (__pmd);                               \
95                 anon_vma_lock(__anon_vma);                              \
96                 anon_vma_unlock(__anon_vma);                            \
97                 BUG_ON(pmd_trans_splitting(*____pmd) ||                 \
98                        pmd_trans_huge(*____pmd));                       \
99         } while (0)
100 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
101 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
102 #if HPAGE_PMD_ORDER > MAX_ORDER
103 #error "hugepages can't be allocated by the buddy allocator"
104 #endif
105 extern int hugepage_madvise(struct vm_area_struct *vma,
106                             unsigned long *vm_flags, int advice);
107 extern void __vma_adjust_trans_huge(struct vm_area_struct *vma,
108                                     unsigned long start,
109                                     unsigned long end,
110                                     long adjust_next);
111 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
112                                          unsigned long start,
113                                          unsigned long end,
114                                          long adjust_next)
115 {
116         if (!vma->anon_vma || vma->vm_ops)
117                 return;
118         __vma_adjust_trans_huge(vma, start, end, adjust_next);
119 }
120 static inline int hpage_nr_pages(struct page *page)
121 {
122         if (unlikely(PageTransHuge(page)))
123                 return HPAGE_PMD_NR;
124         return 1;
125 }
126 static inline struct page *compound_trans_head(struct page *page)
127 {
128         if (PageTail(page)) {
129                 struct page *head;
130                 head = page->first_page;
131                 smp_rmb();
132                 /*
133                  * head may be a dangling pointer.
134                  * __split_huge_page_refcount clears PageTail before
135                  * overwriting first_page, so if PageTail is still
136                  * there it means the head pointer isn't dangling.
137                  */
138                 if (PageTail(page))
139                         return head;
140         }
141         return page;
142 }
143 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
144 #define HPAGE_PMD_SHIFT ({ BUG(); 0; })
145 #define HPAGE_PMD_MASK ({ BUG(); 0; })
146 #define HPAGE_PMD_SIZE ({ BUG(); 0; })
147
148 #define hpage_nr_pages(x) 1
149
150 #define transparent_hugepage_enabled(__vma) 0
151
152 #define transparent_hugepage_flags 0UL
153 static inline int split_huge_page(struct page *page)
154 {
155         return 0;
156 }
157 #define split_huge_page_pmd(__mm, __pmd)        \
158         do { } while (0)
159 #define wait_split_huge_page(__anon_vma, __pmd) \
160         do { } while (0)
161 #define compound_trans_head(page) compound_head(page)
162 static inline int hugepage_madvise(struct vm_area_struct *vma,
163                                    unsigned long *vm_flags, int advice)
164 {
165         BUG();
166         return 0;
167 }
168 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
169                                          unsigned long start,
170                                          unsigned long end,
171                                          long adjust_next)
172 {
173 }
174 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
175
176 #endif /* _LINUX_HUGE_MM_H */