include/linux/huge_mm.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_HUGE_MM_H
   3 #define _LINUX_HUGE_MM_H
   4
   5 #include <linux/sched/coredump.h>
   6
   7 #include <linux/fs.h> /* only for vma_is_dax() */
   8
   9 extern int do_huge_pmd_anonymous_page(struct vm_fault *vmf);
  10 extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
  11                          pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
  12                          struct vm_area_struct *vma);
  13 extern void huge_pmd_set_accessed(struct vm_fault *vmf, pmd_t orig_pmd);
  14 extern int copy_huge_pud(struct mm_struct *dst_mm, struct mm_struct *src_mm,
  15                          pud_t *dst_pud, pud_t *src_pud, unsigned long addr,
  16                          struct vm_area_struct *vma);
  17
  18 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
  19 extern void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud);
  20 #else
  21 static inline void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud)
  22 {
  23 }
  24 #endif
  25
  26 extern int do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd);
  27 extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
  28                                           unsigned long addr,
  29                                           pmd_t *pmd,
  30                                           unsigned int flags);
  31 extern bool madvise_free_huge_pmd(struct mmu_gather *tlb,
  32                         struct vm_area_struct *vma,
  33                         pmd_t *pmd, unsigned long addr, unsigned long next);
  34 extern int zap_huge_pmd(struct mmu_gather *tlb,
  35                         struct vm_area_struct *vma,
  36                         pmd_t *pmd, unsigned long addr);
  37 extern int zap_huge_pud(struct mmu_gather *tlb,
  38                         struct vm_area_struct *vma,
  39                         pud_t *pud, unsigned long addr);
  40 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  41                         unsigned long addr, unsigned long end,
  42                         unsigned char *vec);
  43 extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
  44                          unsigned long new_addr, unsigned long old_end,
  45                          pmd_t *old_pmd, pmd_t *new_pmd, bool *need_flush);
  46 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  47                         unsigned long addr, pgprot_t newprot,
  48                         int prot_numa);
  49 int vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
  50                         pmd_t *pmd, pfn_t pfn, bool write);
  51 int vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
  52                         pud_t *pud, pfn_t pfn, bool write);
  53 enum transparent_hugepage_flag {
  54         TRANSPARENT_HUGEPAGE_FLAG,
  55         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  56         TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
  57         TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
  58         TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG,
  59         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  60         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  61         TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
  62 #ifdef CONFIG_DEBUG_VM
  63         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  64 #endif
  65 };
  66
  67 struct kobject;
  68 struct kobj_attribute;
  69
  70 extern ssize_t single_hugepage_flag_store(struct kobject *kobj,
  71                                  struct kobj_attribute *attr,
  72                                  const char *buf, size_t count,
  73                                  enum transparent_hugepage_flag flag);
  74 extern ssize_t single_hugepage_flag_show(struct kobject *kobj,
  75                                 struct kobj_attribute *attr, char *buf,
  76                                 enum transparent_hugepage_flag flag);
  77 extern struct kobj_attribute shmem_enabled_attr;
  78
  79 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  80 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  81
  82 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  83 #define HPAGE_PMD_SHIFT PMD_SHIFT
  84 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  85 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  86
  87 #define HPAGE_PUD_SHIFT PUD_SHIFT
  88 #define HPAGE_PUD_SIZE  ((1UL) << HPAGE_PUD_SHIFT)
  89 #define HPAGE_PUD_MASK  (~(HPAGE_PUD_SIZE - 1))
  90
  91 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  92
  93 extern unsigned long transparent_hugepage_flags;
  94
  95 static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
  96 {
  97         if (vma->vm_flags & VM_NOHUGEPAGE)
  98                 return false;
  99
 100         if (is_vma_temporary_stack(vma))
 101                 return false;
 102
 103         if (test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
 104                 return false;
 105
 106         if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_FLAG))
 107                 return true;
 108
 109         if (vma_is_dax(vma))
 110                 return true;
 111
 112         if (transparent_hugepage_flags &
 113                                 (1 << TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG))
 114                 return !!(vma->vm_flags & VM_HUGEPAGE);
 115
 116         return false;
 117 }
 118
 119 #define transparent_hugepage_use_zero_page()                            \
 120         (transparent_hugepage_flags &                                   \
 121          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
 122 #ifdef CONFIG_DEBUG_VM
 123 #define transparent_hugepage_debug_cow()                                \
 124         (transparent_hugepage_flags &                                   \
 125          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
 126 #else /* CONFIG_DEBUG_VM */
 127 #define transparent_hugepage_debug_cow() 0
 128 #endif /* CONFIG_DEBUG_VM */
 129
 130 extern unsigned long thp_get_unmapped_area(struct file *filp,
 131                 unsigned long addr, unsigned long len, unsigned long pgoff,
 132                 unsigned long flags);
 133
 134 extern void prep_transhuge_page(struct page *page);
 135 extern void free_transhuge_page(struct page *page);
 136
 137 bool can_split_huge_page(struct page *page, int *pextra_pins);
 138 int split_huge_page_to_list(struct page *page, struct list_head *list);
 139 static inline int split_huge_page(struct page *page)
 140 {
 141         return split_huge_page_to_list(page, NULL);
 142 }
 143 void deferred_split_huge_page(struct page *page);
 144
 145 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 146                 unsigned long address, bool freeze, struct page *page);
 147
 148 #define split_huge_pmd(__vma, __pmd, __address)                         \
 149         do {                                                            \
 150                 pmd_t *____pmd = (__pmd);                               \
 151                 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd)   \
 152                                         || pmd_devmap(*____pmd))        \
 153                         __split_huge_pmd(__vma, __pmd, __address,       \
 154                                                 false, NULL);           \
 155         }  while (0)
 156
 157
 158 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
 159                 bool freeze, struct page *page);
 160
 161 void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud,
 162                 unsigned long address);
 163
 164 #define split_huge_pud(__vma, __pud, __address)                         \
 165         do {                                                            \
 166                 pud_t *____pud = (__pud);                               \
 167                 if (pud_trans_huge(*____pud)                            \
 168                                         || pud_devmap(*____pud))        \
 169                         __split_huge_pud(__vma, __pud, __address);      \
 170         }  while (0)
 171
 172 extern int hugepage_madvise(struct vm_area_struct *vma,
 173                             unsigned long *vm_flags, int advice);
 174 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 175                                     unsigned long start,
 176                                     unsigned long end,
 177                                     long adjust_next);
 178 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
 179                 struct vm_area_struct *vma);
 180 extern spinlock_t *__pud_trans_huge_lock(pud_t *pud,
 181                 struct vm_area_struct *vma);
 182
 183 static inline int is_swap_pmd(pmd_t pmd)
 184 {
 185         return !pmd_none(pmd) && !pmd_present(pmd);
 186 }
 187
 188 /* mmap_sem must be held on entry */
 189 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 190                 struct vm_area_struct *vma)
 191 {
 192         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 193         if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
 194                 return __pmd_trans_huge_lock(pmd, vma);
 195         else
 196                 return NULL;
 197 }
 198 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
 199                 struct vm_area_struct *vma)
 200 {
 201         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 202         if (pud_trans_huge(*pud) || pud_devmap(*pud))
 203                 return __pud_trans_huge_lock(pud, vma);
 204         else
 205                 return NULL;
 206 }
 207 static inline int hpage_nr_pages(struct page *page)
 208 {
 209         if (unlikely(PageTransHuge(page)))
 210                 return HPAGE_PMD_NR;
 211         return 1;
 212 }
 213
 214 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
 215                 pmd_t *pmd, int flags);
 216 struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr,
 217                 pud_t *pud, int flags);
 218
 219 extern int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd);
 220
 221 extern struct page *huge_zero_page;
 222
 223 static inline bool is_huge_zero_page(struct page *page)
 224 {
 225         return ACCESS_ONCE(huge_zero_page) == page;
 226 }
 227
 228 static inline bool is_huge_zero_pmd(pmd_t pmd)
 229 {
 230         return is_huge_zero_page(pmd_page(pmd));
 231 }
 232
 233 static inline bool is_huge_zero_pud(pud_t pud)
 234 {
 235         return false;
 236 }
 237
 238 struct page *mm_get_huge_zero_page(struct mm_struct *mm);
 239 void mm_put_huge_zero_page(struct mm_struct *mm);
 240
 241 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
 242
 243 static inline bool thp_migration_supported(void)
 244 {
 245         return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION);
 246 }
 247
 248 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 249 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 250 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 251 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 252
 253 #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; })
 254 #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; })
 255 #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; })
 256
 257 #define hpage_nr_pages(x) 1
 258
 259 static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
 260 {
 261         return false;
 262 }
 263
 264 static inline void prep_transhuge_page(struct page *page) {}
 265
 266 #define transparent_hugepage_flags 0UL
 267
 268 #define thp_get_unmapped_area   NULL
 269
 270 static inline bool
 271 can_split_huge_page(struct page *page, int *pextra_pins)
 272 {
 273         BUILD_BUG();
 274         return false;
 275 }
 276 static inline int
 277 split_huge_page_to_list(struct page *page, struct list_head *list)
 278 {
 279         return 0;
 280 }
 281 static inline int split_huge_page(struct page *page)
 282 {
 283         return 0;
 284 }
 285 static inline void deferred_split_huge_page(struct page *page) {}
 286 #define split_huge_pmd(__vma, __pmd, __address) \
 287         do { } while (0)
 288
 289 static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 290                 unsigned long address, bool freeze, struct page *page) {}
 291 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
 292                 unsigned long address, bool freeze, struct page *page) {}
 293
 294 #define split_huge_pud(__vma, __pmd, __address) \
 295         do { } while (0)
 296
 297 static inline int hugepage_madvise(struct vm_area_struct *vma,
 298                                    unsigned long *vm_flags, int advice)
 299 {
 300         BUG();
 301         return 0;
 302 }
 303 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 304                                          unsigned long start,
 305                                          unsigned long end,
 306                                          long adjust_next)
 307 {
 308 }
 309 static inline int is_swap_pmd(pmd_t pmd)
 310 {
 311         return 0;
 312 }
 313 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 314                 struct vm_area_struct *vma)
 315 {
 316         return NULL;
 317 }
 318 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
 319                 struct vm_area_struct *vma)
 320 {
 321         return NULL;
 322 }
 323
 324 static inline int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd)
 325 {
 326         return 0;
 327 }
 328
 329 static inline bool is_huge_zero_page(struct page *page)
 330 {
 331         return false;
 332 }
 333
 334 static inline bool is_huge_zero_pud(pud_t pud)
 335 {
 336         return false;
 337 }
 338
 339 static inline void mm_put_huge_zero_page(struct mm_struct *mm)
 340 {
 341         return;
 342 }
 343
 344 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
 345                 unsigned long addr, pmd_t *pmd, int flags)
 346 {
 347         return NULL;
 348 }
 349
 350 static inline struct page *follow_devmap_pud(struct vm_area_struct *vma,
 351                 unsigned long addr, pud_t *pud, int flags)
 352 {
 353         return NULL;
 354 }
 355
 356 static inline bool thp_migration_supported(void)
 357 {
 358         return false;
 359 }
 360 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 361
 362 #endif /* _LINUX_HUGE_MM_H */