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 bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr, 42 unsigned long new_addr, 43 pmd_t *old_pmd, pmd_t *new_pmd); 44 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 45 unsigned long addr, pgprot_t newprot, 46 unsigned long cp_flags); 47 vm_fault_t vmf_insert_pfn_pmd_prot(struct vm_fault *vmf, pfn_t pfn, 48 pgprot_t pgprot, bool write); 49 50 /** 51 * vmf_insert_pfn_pmd - insert a pmd size pfn 52 * @vmf: Structure describing the fault 53 * @pfn: pfn to insert 54 * @pgprot: page protection to use 55 * @write: whether it's a write fault 56 * 57 * Insert a pmd size pfn. See vmf_insert_pfn() for additional info. 58 * 59 * Return: vm_fault_t value. 60 */ 61 static inline vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, 62 bool write) 63 { 64 return vmf_insert_pfn_pmd_prot(vmf, pfn, vmf->vma->vm_page_prot, write); 65 } 66 vm_fault_t vmf_insert_pfn_pud_prot(struct vm_fault *vmf, pfn_t pfn, 67 pgprot_t pgprot, bool write); 68 69 /** 70 * vmf_insert_pfn_pud - insert a pud size pfn 71 * @vmf: Structure describing the fault 72 * @pfn: pfn to insert 73 * @pgprot: page protection to use 74 * @write: whether it's a write fault 75 * 76 * Insert a pud size pfn. See vmf_insert_pfn() for additional info. 77 * 78 * Return: vm_fault_t value. 79 */ 80 static inline vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, 81 bool write) 82 { 83 return vmf_insert_pfn_pud_prot(vmf, pfn, vmf->vma->vm_page_prot, write); 84 } 85 86 enum transparent_hugepage_flag { 87 TRANSPARENT_HUGEPAGE_FLAG, 88 TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, 89 TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, 90 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG, 91 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG, 92 TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, 93 TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG, 94 TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG, 95 #ifdef CONFIG_DEBUG_VM 96 TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG, 97 #endif 98 }; 99 100 struct kobject; 101 struct kobj_attribute; 102 103 extern ssize_t single_hugepage_flag_store(struct kobject *kobj, 104 struct kobj_attribute *attr, 105 const char *buf, size_t count, 106 enum transparent_hugepage_flag flag); 107 extern ssize_t single_hugepage_flag_show(struct kobject *kobj, 108 struct kobj_attribute *attr, char *buf, 109 enum transparent_hugepage_flag flag); 110 extern struct kobj_attribute shmem_enabled_attr; 111 112 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) 113 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) 114 115 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 116 #define HPAGE_PMD_SHIFT PMD_SHIFT 117 #define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT) 118 #define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1)) 119 120 #define HPAGE_PUD_SHIFT PUD_SHIFT 121 #define HPAGE_PUD_SIZE ((1UL) << HPAGE_PUD_SHIFT) 122 #define HPAGE_PUD_MASK (~(HPAGE_PUD_SIZE - 1)) 123 124 extern unsigned long transparent_hugepage_flags; 125 126 /* 127 * to be used on vmas which are known to support THP. 128 * Use transparent_hugepage_enabled otherwise 129 */ 130 static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma) 131 { 132 if (vma->vm_flags & VM_NOHUGEPAGE) 133 return false; 134 135 if (vma_is_temporary_stack(vma)) 136 return false; 137 138 if (test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags)) 139 return false; 140 141 if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_FLAG)) 142 return true; 143 /* 144 * For dax vmas, try to always use hugepage mappings. If the kernel does 145 * not support hugepages, fsdax mappings will fallback to PAGE_SIZE 146 * mappings, and device-dax namespaces, that try to guarantee a given 147 * mapping size, will fail to enable 148 */ 149 if (vma_is_dax(vma)) 150 return true; 151 152 if (transparent_hugepage_flags & 153 (1 << TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG)) 154 return !!(vma->vm_flags & VM_HUGEPAGE); 155 156 return false; 157 } 158 159 bool transparent_hugepage_enabled(struct vm_area_struct *vma); 160 161 #define HPAGE_CACHE_INDEX_MASK (HPAGE_PMD_NR - 1) 162 163 static inline bool transhuge_vma_suitable(struct vm_area_struct *vma, 164 unsigned long haddr) 165 { 166 /* Don't have to check pgoff for anonymous vma */ 167 if (!vma_is_anonymous(vma)) { 168 if (((vma->vm_start >> PAGE_SHIFT) & HPAGE_CACHE_INDEX_MASK) != 169 (vma->vm_pgoff & HPAGE_CACHE_INDEX_MASK)) 170 return false; 171 } 172 173 if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end) 174 return false; 175 return true; 176 } 177 178 #define transparent_hugepage_use_zero_page() \ 179 (transparent_hugepage_flags & \ 180 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG)) 181 182 extern unsigned long thp_get_unmapped_area(struct file *filp, 183 unsigned long addr, unsigned long len, unsigned long pgoff, 184 unsigned long flags); 185 186 extern void prep_transhuge_page(struct page *page); 187 extern void free_transhuge_page(struct page *page); 188 bool is_transparent_hugepage(struct page *page); 189 190 bool can_split_huge_page(struct page *page, int *pextra_pins); 191 int split_huge_page_to_list(struct page *page, struct list_head *list); 192 static inline int split_huge_page(struct page *page) 193 { 194 return split_huge_page_to_list(page, NULL); 195 } 196 void deferred_split_huge_page(struct page *page); 197 198 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 199 unsigned long address, bool freeze, struct page *page); 200 201 #define split_huge_pmd(__vma, __pmd, __address) \ 202 do { \ 203 pmd_t *____pmd = (__pmd); \ 204 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd) \ 205 || pmd_devmap(*____pmd)) \ 206 __split_huge_pmd(__vma, __pmd, __address, \ 207 false, NULL); \ 208 } while (0) 209 210 211 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, 212 bool freeze, struct page *page); 213 214 void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud, 215 unsigned long address); 216 217 #define split_huge_pud(__vma, __pud, __address) \ 218 do { \ 219 pud_t *____pud = (__pud); \ 220 if (pud_trans_huge(*____pud) \ 221 || pud_devmap(*____pud)) \ 222 __split_huge_pud(__vma, __pud, __address); \ 223 } while (0) 224 225 extern int hugepage_madvise(struct vm_area_struct *vma, 226 unsigned long *vm_flags, int advice); 227 extern void vma_adjust_trans_huge(struct vm_area_struct *vma, 228 unsigned long start, 229 unsigned long end, 230 long adjust_next); 231 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, 232 struct vm_area_struct *vma); 233 extern spinlock_t *__pud_trans_huge_lock(pud_t *pud, 234 struct vm_area_struct *vma); 235 236 static inline int is_swap_pmd(pmd_t pmd) 237 { 238 return !pmd_none(pmd) && !pmd_present(pmd); 239 } 240 241 /* mmap_lock must be held on entry */ 242 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 243 struct vm_area_struct *vma) 244 { 245 if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) 246 return __pmd_trans_huge_lock(pmd, vma); 247 else 248 return NULL; 249 } 250 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 251 struct vm_area_struct *vma) 252 { 253 if (pud_trans_huge(*pud) || pud_devmap(*pud)) 254 return __pud_trans_huge_lock(pud, vma); 255 else 256 return NULL; 257 } 258 259 /** 260 * thp_head - Head page of a transparent huge page. 261 * @page: Any page (tail, head or regular) found in the page cache. 262 */ 263 static inline struct page *thp_head(struct page *page) 264 { 265 return compound_head(page); 266 } 267 268 /** 269 * thp_order - Order of a transparent huge page. 270 * @page: Head page of a transparent huge page. 271 */ 272 static inline unsigned int thp_order(struct page *page) 273 { 274 VM_BUG_ON_PGFLAGS(PageTail(page), page); 275 if (PageHead(page)) 276 return HPAGE_PMD_ORDER; 277 return 0; 278 } 279 280 /** 281 * thp_nr_pages - The number of regular pages in this huge page. 282 * @page: The head page of a huge page. 283 */ 284 static inline int thp_nr_pages(struct page *page) 285 { 286 VM_BUG_ON_PGFLAGS(PageTail(page), page); 287 if (PageHead(page)) 288 return HPAGE_PMD_NR; 289 return 1; 290 } 291 292 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr, 293 pmd_t *pmd, int flags, struct dev_pagemap **pgmap); 294 struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr, 295 pud_t *pud, int flags, struct dev_pagemap **pgmap); 296 297 extern vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd); 298 299 extern struct page *huge_zero_page; 300 301 static inline bool is_huge_zero_page(struct page *page) 302 { 303 return READ_ONCE(huge_zero_page) == page; 304 } 305 306 static inline bool is_huge_zero_pmd(pmd_t pmd) 307 { 308 return is_huge_zero_page(pmd_page(pmd)); 309 } 310 311 static inline bool is_huge_zero_pud(pud_t pud) 312 { 313 return false; 314 } 315 316 struct page *mm_get_huge_zero_page(struct mm_struct *mm); 317 void mm_put_huge_zero_page(struct mm_struct *mm); 318 319 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot)) 320 321 static inline bool thp_migration_supported(void) 322 { 323 return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION); 324 } 325 326 static inline struct list_head *page_deferred_list(struct page *page) 327 { 328 /* 329 * Global or memcg deferred list in the second tail pages is 330 * occupied by compound_head. 331 */ 332 return &page[2].deferred_list; 333 } 334 335 #else /* CONFIG_TRANSPARENT_HUGEPAGE */ 336 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) 337 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; }) 338 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; }) 339 340 #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; }) 341 #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; }) 342 #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; }) 343 344 static inline struct page *thp_head(struct page *page) 345 { 346 VM_BUG_ON_PGFLAGS(PageTail(page), page); 347 return page; 348 } 349 350 static inline unsigned int thp_order(struct page *page) 351 { 352 VM_BUG_ON_PGFLAGS(PageTail(page), page); 353 return 0; 354 } 355 356 static inline int thp_nr_pages(struct page *page) 357 { 358 VM_BUG_ON_PGFLAGS(PageTail(page), page); 359 return 1; 360 } 361 362 static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma) 363 { 364 return false; 365 } 366 367 static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma) 368 { 369 return false; 370 } 371 372 static inline bool transhuge_vma_suitable(struct vm_area_struct *vma, 373 unsigned long haddr) 374 { 375 return false; 376 } 377 378 static inline void prep_transhuge_page(struct page *page) {} 379 380 static inline bool is_transparent_hugepage(struct page *page) 381 { 382 return false; 383 } 384 385 #define transparent_hugepage_flags 0UL 386 387 #define thp_get_unmapped_area NULL 388 389 static inline bool 390 can_split_huge_page(struct page *page, int *pextra_pins) 391 { 392 BUILD_BUG(); 393 return false; 394 } 395 static inline int 396 split_huge_page_to_list(struct page *page, struct list_head *list) 397 { 398 return 0; 399 } 400 static inline int split_huge_page(struct page *page) 401 { 402 return 0; 403 } 404 static inline void deferred_split_huge_page(struct page *page) {} 405 #define split_huge_pmd(__vma, __pmd, __address) \ 406 do { } while (0) 407 408 static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 409 unsigned long address, bool freeze, struct page *page) {} 410 static inline void split_huge_pmd_address(struct vm_area_struct *vma, 411 unsigned long address, bool freeze, struct page *page) {} 412 413 #define split_huge_pud(__vma, __pmd, __address) \ 414 do { } while (0) 415 416 static inline int hugepage_madvise(struct vm_area_struct *vma, 417 unsigned long *vm_flags, int advice) 418 { 419 BUG(); 420 return 0; 421 } 422 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, 423 unsigned long start, 424 unsigned long end, 425 long adjust_next) 426 { 427 } 428 static inline int is_swap_pmd(pmd_t pmd) 429 { 430 return 0; 431 } 432 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 433 struct vm_area_struct *vma) 434 { 435 return NULL; 436 } 437 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 438 struct vm_area_struct *vma) 439 { 440 return NULL; 441 } 442 443 static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, 444 pmd_t orig_pmd) 445 { 446 return 0; 447 } 448 449 static inline bool is_huge_zero_page(struct page *page) 450 { 451 return false; 452 } 453 454 static inline bool is_huge_zero_pud(pud_t pud) 455 { 456 return false; 457 } 458 459 static inline void mm_put_huge_zero_page(struct mm_struct *mm) 460 { 461 return; 462 } 463 464 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma, 465 unsigned long addr, pmd_t *pmd, int flags, struct dev_pagemap **pgmap) 466 { 467 return NULL; 468 } 469 470 static inline struct page *follow_devmap_pud(struct vm_area_struct *vma, 471 unsigned long addr, pud_t *pud, int flags, struct dev_pagemap **pgmap) 472 { 473 return NULL; 474 } 475 476 static inline bool thp_migration_supported(void) 477 { 478 return false; 479 } 480 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 481 482 /** 483 * thp_size - Size of a transparent huge page. 484 * @page: Head page of a transparent huge page. 485 * 486 * Return: Number of bytes in this page. 487 */ 488 static inline unsigned long thp_size(struct page *page) 489 { 490 return PAGE_SIZE << thp_order(page); 491 } 492 493 #endif /* _LINUX_HUGE_MM_H */ 494