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