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_fault *vmf, pfn_t pfn, bool write); 51 vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write); 52 enum transparent_hugepage_flag { 53 TRANSPARENT_HUGEPAGE_FLAG, 54 TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, 55 TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, 56 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG, 57 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG, 58 TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, 59 TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG, 60 TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG, 61 #ifdef CONFIG_DEBUG_VM 62 TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG, 63 #endif 64 }; 65 66 struct kobject; 67 struct kobj_attribute; 68 69 extern ssize_t single_hugepage_flag_store(struct kobject *kobj, 70 struct kobj_attribute *attr, 71 const char *buf, size_t count, 72 enum transparent_hugepage_flag flag); 73 extern ssize_t single_hugepage_flag_show(struct kobject *kobj, 74 struct kobj_attribute *attr, char *buf, 75 enum transparent_hugepage_flag flag); 76 extern struct kobj_attribute shmem_enabled_attr; 77 78 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) 79 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) 80 81 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 82 #define HPAGE_PMD_SHIFT PMD_SHIFT 83 #define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT) 84 #define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1)) 85 86 #define HPAGE_PUD_SHIFT PUD_SHIFT 87 #define HPAGE_PUD_SIZE ((1UL) << HPAGE_PUD_SHIFT) 88 #define HPAGE_PUD_MASK (~(HPAGE_PUD_SIZE - 1)) 89 90 extern bool is_vma_temporary_stack(struct vm_area_struct *vma); 91 92 extern unsigned long transparent_hugepage_flags; 93 94 /* 95 * to be used on vmas which are known to support THP. 96 * Use transparent_hugepage_enabled otherwise 97 */ 98 static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma) 99 { 100 if (vma->vm_flags & VM_NOHUGEPAGE) 101 return false; 102 103 if (is_vma_temporary_stack(vma)) 104 return false; 105 106 if (test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags)) 107 return false; 108 109 if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_FLAG)) 110 return true; 111 /* 112 * For dax vmas, try to always use hugepage mappings. If the kernel does 113 * not support hugepages, fsdax mappings will fallback to PAGE_SIZE 114 * mappings, and device-dax namespaces, that try to guarantee a given 115 * mapping size, will fail to enable 116 */ 117 if (vma_is_dax(vma)) 118 return true; 119 120 if (transparent_hugepage_flags & 121 (1 << TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG)) 122 return !!(vma->vm_flags & VM_HUGEPAGE); 123 124 return false; 125 } 126 127 bool transparent_hugepage_enabled(struct vm_area_struct *vma); 128 129 #define HPAGE_CACHE_INDEX_MASK (HPAGE_PMD_NR - 1) 130 131 static inline bool transhuge_vma_suitable(struct vm_area_struct *vma, 132 unsigned long haddr) 133 { 134 /* Don't have to check pgoff for anonymous vma */ 135 if (!vma_is_anonymous(vma)) { 136 if (((vma->vm_start >> PAGE_SHIFT) & HPAGE_CACHE_INDEX_MASK) != 137 (vma->vm_pgoff & HPAGE_CACHE_INDEX_MASK)) 138 return false; 139 } 140 141 if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end) 142 return false; 143 return true; 144 } 145 146 #define transparent_hugepage_use_zero_page() \ 147 (transparent_hugepage_flags & \ 148 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG)) 149 #ifdef CONFIG_DEBUG_VM 150 #define transparent_hugepage_debug_cow() \ 151 (transparent_hugepage_flags & \ 152 (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG)) 153 #else /* CONFIG_DEBUG_VM */ 154 #define transparent_hugepage_debug_cow() 0 155 #endif /* CONFIG_DEBUG_VM */ 156 157 extern unsigned long thp_get_unmapped_area(struct file *filp, 158 unsigned long addr, unsigned long len, unsigned long pgoff, 159 unsigned long flags); 160 161 extern void prep_transhuge_page(struct page *page); 162 extern void free_transhuge_page(struct page *page); 163 164 bool can_split_huge_page(struct page *page, int *pextra_pins); 165 int split_huge_page_to_list(struct page *page, struct list_head *list); 166 static inline int split_huge_page(struct page *page) 167 { 168 return split_huge_page_to_list(page, NULL); 169 } 170 void deferred_split_huge_page(struct page *page); 171 172 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 173 unsigned long address, bool freeze, struct page *page); 174 175 #define split_huge_pmd(__vma, __pmd, __address) \ 176 do { \ 177 pmd_t *____pmd = (__pmd); \ 178 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd) \ 179 || pmd_devmap(*____pmd)) \ 180 __split_huge_pmd(__vma, __pmd, __address, \ 181 false, NULL); \ 182 } while (0) 183 184 185 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, 186 bool freeze, struct page *page); 187 188 void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud, 189 unsigned long address); 190 191 #define split_huge_pud(__vma, __pud, __address) \ 192 do { \ 193 pud_t *____pud = (__pud); \ 194 if (pud_trans_huge(*____pud) \ 195 || pud_devmap(*____pud)) \ 196 __split_huge_pud(__vma, __pud, __address); \ 197 } while (0) 198 199 extern int hugepage_madvise(struct vm_area_struct *vma, 200 unsigned long *vm_flags, int advice); 201 extern void vma_adjust_trans_huge(struct vm_area_struct *vma, 202 unsigned long start, 203 unsigned long end, 204 long adjust_next); 205 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, 206 struct vm_area_struct *vma); 207 extern spinlock_t *__pud_trans_huge_lock(pud_t *pud, 208 struct vm_area_struct *vma); 209 210 static inline int is_swap_pmd(pmd_t pmd) 211 { 212 return !pmd_none(pmd) && !pmd_present(pmd); 213 } 214 215 /* mmap_sem must be held on entry */ 216 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 217 struct vm_area_struct *vma) 218 { 219 if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) 220 return __pmd_trans_huge_lock(pmd, vma); 221 else 222 return NULL; 223 } 224 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 225 struct vm_area_struct *vma) 226 { 227 if (pud_trans_huge(*pud) || pud_devmap(*pud)) 228 return __pud_trans_huge_lock(pud, vma); 229 else 230 return NULL; 231 } 232 static inline int hpage_nr_pages(struct page *page) 233 { 234 if (unlikely(PageTransHuge(page))) 235 return HPAGE_PMD_NR; 236 return 1; 237 } 238 239 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr, 240 pmd_t *pmd, int flags, struct dev_pagemap **pgmap); 241 struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr, 242 pud_t *pud, int flags, struct dev_pagemap **pgmap); 243 244 extern vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd); 245 246 extern struct page *huge_zero_page; 247 248 static inline bool is_huge_zero_page(struct page *page) 249 { 250 return READ_ONCE(huge_zero_page) == page; 251 } 252 253 static inline bool is_huge_zero_pmd(pmd_t pmd) 254 { 255 return is_huge_zero_page(pmd_page(pmd)); 256 } 257 258 static inline bool is_huge_zero_pud(pud_t pud) 259 { 260 return false; 261 } 262 263 struct page *mm_get_huge_zero_page(struct mm_struct *mm); 264 void mm_put_huge_zero_page(struct mm_struct *mm); 265 266 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot)) 267 268 static inline bool thp_migration_supported(void) 269 { 270 return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION); 271 } 272 273 static inline struct list_head *page_deferred_list(struct page *page) 274 { 275 /* 276 * Global or memcg deferred list in the second tail pages is 277 * occupied by compound_head. 278 */ 279 return &page[2].deferred_list; 280 } 281 282 #else /* CONFIG_TRANSPARENT_HUGEPAGE */ 283 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) 284 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; }) 285 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; }) 286 287 #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; }) 288 #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; }) 289 #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; }) 290 291 #define hpage_nr_pages(x) 1 292 293 static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma) 294 { 295 return false; 296 } 297 298 static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma) 299 { 300 return false; 301 } 302 303 static inline bool transhuge_vma_suitable(struct vm_area_struct *vma, 304 unsigned long haddr) 305 { 306 return false; 307 } 308 309 static inline void prep_transhuge_page(struct page *page) {} 310 311 #define transparent_hugepage_flags 0UL 312 313 #define thp_get_unmapped_area NULL 314 315 static inline bool 316 can_split_huge_page(struct page *page, int *pextra_pins) 317 { 318 BUILD_BUG(); 319 return false; 320 } 321 static inline int 322 split_huge_page_to_list(struct page *page, struct list_head *list) 323 { 324 return 0; 325 } 326 static inline int split_huge_page(struct page *page) 327 { 328 return 0; 329 } 330 static inline void deferred_split_huge_page(struct page *page) {} 331 #define split_huge_pmd(__vma, __pmd, __address) \ 332 do { } while (0) 333 334 static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 335 unsigned long address, bool freeze, struct page *page) {} 336 static inline void split_huge_pmd_address(struct vm_area_struct *vma, 337 unsigned long address, bool freeze, struct page *page) {} 338 339 #define split_huge_pud(__vma, __pmd, __address) \ 340 do { } while (0) 341 342 static inline int hugepage_madvise(struct vm_area_struct *vma, 343 unsigned long *vm_flags, int advice) 344 { 345 BUG(); 346 return 0; 347 } 348 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, 349 unsigned long start, 350 unsigned long end, 351 long adjust_next) 352 { 353 } 354 static inline int is_swap_pmd(pmd_t pmd) 355 { 356 return 0; 357 } 358 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 359 struct vm_area_struct *vma) 360 { 361 return NULL; 362 } 363 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 364 struct vm_area_struct *vma) 365 { 366 return NULL; 367 } 368 369 static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, 370 pmd_t orig_pmd) 371 { 372 return 0; 373 } 374 375 static inline bool is_huge_zero_page(struct page *page) 376 { 377 return false; 378 } 379 380 static inline bool is_huge_zero_pud(pud_t pud) 381 { 382 return false; 383 } 384 385 static inline void mm_put_huge_zero_page(struct mm_struct *mm) 386 { 387 return; 388 } 389 390 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma, 391 unsigned long addr, pmd_t *pmd, int flags, struct dev_pagemap **pgmap) 392 { 393 return NULL; 394 } 395 396 static inline struct page *follow_devmap_pud(struct vm_area_struct *vma, 397 unsigned long addr, pud_t *pud, int flags, struct dev_pagemap **pgmap) 398 { 399 return NULL; 400 } 401 402 static inline bool thp_migration_supported(void) 403 { 404 return false; 405 } 406 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 407 408 #endif /* _LINUX_HUGE_MM_H */ 409