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 #include <linux/mm_types.h>
   7
   8 #include <linux/fs.h> /* only for vma_is_dax() */
   9
  10 extern vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf);
  11 extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
  12                          pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
  13                          struct vm_area_struct *vma);
  14 extern void huge_pmd_set_accessed(struct vm_fault *vmf, pmd_t orig_pmd);
  15 extern int copy_huge_pud(struct mm_struct *dst_mm, struct mm_struct *src_mm,
  16                          pud_t *dst_pud, pud_t *src_pud, unsigned long addr,
  17                          struct vm_area_struct *vma);
  18
  19 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
  20 extern void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud);
  21 #else
  22 static inline void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud)
  23 {
  24 }
  25 #endif
  26
  27 extern vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd);
  28 extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
  29                                           unsigned long addr,
  30                                           pmd_t *pmd,
  31                                           unsigned int flags);
  32 extern bool madvise_free_huge_pmd(struct mmu_gather *tlb,
  33                         struct vm_area_struct *vma,
  34                         pmd_t *pmd, unsigned long addr, unsigned long next);
  35 extern int zap_huge_pmd(struct mmu_gather *tlb,
  36                         struct vm_area_struct *vma,
  37                         pmd_t *pmd, unsigned long addr);
  38 extern int zap_huge_pud(struct mmu_gather *tlb,
  39                         struct vm_area_struct *vma,
  40                         pud_t *pud, unsigned long addr);
  41 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  42                         unsigned long addr, unsigned long end,
  43                         unsigned char *vec);
  44 extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
  45                          unsigned long new_addr, unsigned long old_end,
  46                          pmd_t *old_pmd, pmd_t *new_pmd);
  47 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  48                         unsigned long addr, pgprot_t newprot,
  49                         int prot_numa);
  50 vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
  51                         pmd_t *pmd, pfn_t pfn, bool write);
  52 vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
  53                         pud_t *pud, pfn_t pfn, bool write);
  54 enum transparent_hugepage_flag {
  55         TRANSPARENT_HUGEPAGE_FLAG,
  56         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  57         TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
  58         TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
  59         TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG,
  60         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  61         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  62         TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
  63 #ifdef CONFIG_DEBUG_VM
  64         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  65 #endif
  66 };
  67
  68 struct kobject;
  69 struct kobj_attribute;
  70
  71 extern ssize_t single_hugepage_flag_store(struct kobject *kobj,
  72                                  struct kobj_attribute *attr,
  73                                  const char *buf, size_t count,
  74                                  enum transparent_hugepage_flag flag);
  75 extern ssize_t single_hugepage_flag_show(struct kobject *kobj,
  76                                 struct kobj_attribute *attr, char *buf,
  77                                 enum transparent_hugepage_flag flag);
  78 extern struct kobj_attribute shmem_enabled_attr;
  79
  80 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  81 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  82
  83 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  84 #define HPAGE_PMD_SHIFT PMD_SHIFT
  85 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  86 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  87
  88 #define HPAGE_PUD_SHIFT PUD_SHIFT
  89 #define HPAGE_PUD_SIZE  ((1UL) << HPAGE_PUD_SHIFT)
  90 #define HPAGE_PUD_MASK  (~(HPAGE_PUD_SIZE - 1))
  91
  92 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  93
  94 extern unsigned long transparent_hugepage_flags;
  95
  96 /*
  97  * to be used on vmas which are known to support THP.
  98  * Use transparent_hugepage_enabled otherwise
  99  */
 100 static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
 101 {
 102         if (vma->vm_flags & VM_NOHUGEPAGE)
 103                 return false;
 104
 105         if (is_vma_temporary_stack(vma))
 106                 return false;
 107
 108         if (test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
 109                 return false;
 110
 111         if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_FLAG))
 112                 return true;
 113
 114         if (vma_is_dax(vma))
 115                 return true;
 116
 117         if (transparent_hugepage_flags &
 118                                 (1 << TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG))
 119                 return !!(vma->vm_flags & VM_HUGEPAGE);
 120
 121         return false;
 122 }
 123
 124 bool transparent_hugepage_enabled(struct vm_area_struct *vma);
 125
 126 #define transparent_hugepage_use_zero_page()                            \
 127         (transparent_hugepage_flags &                                   \
 128          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
 129 #ifdef CONFIG_DEBUG_VM
 130 #define transparent_hugepage_debug_cow()                                \
 131         (transparent_hugepage_flags &                                   \
 132          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
 133 #else /* CONFIG_DEBUG_VM */
 134 #define transparent_hugepage_debug_cow() 0
 135 #endif /* CONFIG_DEBUG_VM */
 136
 137 extern unsigned long thp_get_unmapped_area(struct file *filp,
 138                 unsigned long addr, unsigned long len, unsigned long pgoff,
 139                 unsigned long flags);
 140
 141 extern void prep_transhuge_page(struct page *page);
 142 extern void free_transhuge_page(struct page *page);
 143
 144 bool can_split_huge_page(struct page *page, int *pextra_pins);
 145 int split_huge_page_to_list(struct page *page, struct list_head *list);
 146 static inline int split_huge_page(struct page *page)
 147 {
 148         return split_huge_page_to_list(page, NULL);
 149 }
 150 void deferred_split_huge_page(struct page *page);
 151
 152 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 153                 unsigned long address, bool freeze, struct page *page);
 154
 155 #define split_huge_pmd(__vma, __pmd, __address)                         \
 156         do {                                                            \
 157                 pmd_t *____pmd = (__pmd);                               \
 158                 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd)   \
 159                                         || pmd_devmap(*____pmd))        \
 160                         __split_huge_pmd(__vma, __pmd, __address,       \
 161                                                 false, NULL);           \
 162         }  while (0)
 163
 164
 165 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
 166                 bool freeze, struct page *page);
 167
 168 void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud,
 169                 unsigned long address);
 170
 171 #define split_huge_pud(__vma, __pud, __address)                         \
 172         do {                                                            \
 173                 pud_t *____pud = (__pud);                               \
 174                 if (pud_trans_huge(*____pud)                            \
 175                                         || pud_devmap(*____pud))        \
 176                         __split_huge_pud(__vma, __pud, __address);      \
 177         }  while (0)
 178
 179 extern int hugepage_madvise(struct vm_area_struct *vma,
 180                             unsigned long *vm_flags, int advice);
 181 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 182                                     unsigned long start,
 183                                     unsigned long end,
 184                                     long adjust_next);
 185 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
 186                 struct vm_area_struct *vma);
 187 extern spinlock_t *__pud_trans_huge_lock(pud_t *pud,
 188                 struct vm_area_struct *vma);
 189
 190 static inline int is_swap_pmd(pmd_t pmd)
 191 {
 192         return !pmd_none(pmd) && !pmd_present(pmd);
 193 }
 194
 195 /* mmap_sem must be held on entry */
 196 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 197                 struct vm_area_struct *vma)
 198 {
 199         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 200         if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
 201                 return __pmd_trans_huge_lock(pmd, vma);
 202         else
 203                 return NULL;
 204 }
 205 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
 206                 struct vm_area_struct *vma)
 207 {
 208         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 209         if (pud_trans_huge(*pud) || pud_devmap(*pud))
 210                 return __pud_trans_huge_lock(pud, vma);
 211         else
 212                 return NULL;
 213 }
 214 static inline int hpage_nr_pages(struct page *page)
 215 {
 216         if (unlikely(PageTransHuge(page)))
 217                 return HPAGE_PMD_NR;
 218         return 1;
 219 }
 220
 221 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
 222                 pmd_t *pmd, int flags, struct dev_pagemap **pgmap);
 223 struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr,
 224                 pud_t *pud, int flags, struct dev_pagemap **pgmap);
 225
 226 extern vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd);
 227
 228 extern struct page *huge_zero_page;
 229
 230 static inline bool is_huge_zero_page(struct page *page)
 231 {
 232         return READ_ONCE(huge_zero_page) == page;
 233 }
 234
 235 static inline bool is_huge_zero_pmd(pmd_t pmd)
 236 {
 237         return is_huge_zero_page(pmd_page(pmd));
 238 }
 239
 240 static inline bool is_huge_zero_pud(pud_t pud)
 241 {
 242         return false;
 243 }
 244
 245 struct page *mm_get_huge_zero_page(struct mm_struct *mm);
 246 void mm_put_huge_zero_page(struct mm_struct *mm);
 247
 248 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
 249
 250 static inline bool thp_migration_supported(void)
 251 {
 252         return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION);
 253 }
 254
 255 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 256 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 257 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 258 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 259
 260 #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; })
 261 #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; })
 262 #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; })
 263
 264 #define hpage_nr_pages(x) 1
 265
 266 static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
 267 {
 268         return false;
 269 }
 270
 271 static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
 272 {
 273         return false;
 274 }
 275
 276 static inline void prep_transhuge_page(struct page *page) {}
 277
 278 #define transparent_hugepage_flags 0UL
 279
 280 #define thp_get_unmapped_area   NULL
 281
 282 static inline bool
 283 can_split_huge_page(struct page *page, int *pextra_pins)
 284 {
 285         BUILD_BUG();
 286         return false;
 287 }
 288 static inline int
 289 split_huge_page_to_list(struct page *page, struct list_head *list)
 290 {
 291         return 0;
 292 }
 293 static inline int split_huge_page(struct page *page)
 294 {
 295         return 0;
 296 }
 297 static inline void deferred_split_huge_page(struct page *page) {}
 298 #define split_huge_pmd(__vma, __pmd, __address) \
 299         do { } while (0)
 300
 301 static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 302                 unsigned long address, bool freeze, struct page *page) {}
 303 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
 304                 unsigned long address, bool freeze, struct page *page) {}
 305
 306 #define split_huge_pud(__vma, __pmd, __address) \
 307         do { } while (0)
 308
 309 static inline int hugepage_madvise(struct vm_area_struct *vma,
 310                                    unsigned long *vm_flags, int advice)
 311 {
 312         BUG();
 313         return 0;
 314 }
 315 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 316                                          unsigned long start,
 317                                          unsigned long end,
 318                                          long adjust_next)
 319 {
 320 }
 321 static inline int is_swap_pmd(pmd_t pmd)
 322 {
 323         return 0;
 324 }
 325 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 326                 struct vm_area_struct *vma)
 327 {
 328         return NULL;
 329 }
 330 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
 331                 struct vm_area_struct *vma)
 332 {
 333         return NULL;
 334 }
 335
 336 static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf,
 337                 pmd_t orig_pmd)
 338 {
 339         return 0;
 340 }
 341
 342 static inline bool is_huge_zero_page(struct page *page)
 343 {
 344         return false;
 345 }
 346
 347 static inline bool is_huge_zero_pud(pud_t pud)
 348 {
 349         return false;
 350 }
 351
 352 static inline void mm_put_huge_zero_page(struct mm_struct *mm)
 353 {
 354         return;
 355 }
 356
 357 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
 358         unsigned long addr, pmd_t *pmd, int flags, struct dev_pagemap **pgmap)
 359 {
 360         return NULL;
 361 }
 362
 363 static inline struct page *follow_devmap_pud(struct vm_area_struct *vma,
 364         unsigned long addr, pud_t *pud, int flags, struct dev_pagemap **pgmap)
 365 {
 366         return NULL;
 367 }
 368
 369 static inline bool thp_migration_supported(void)
 370 {
 371         return false;
 372 }
 373 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 374
 375 #endif /* _LINUX_HUGE_MM_H */