1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef MM_SLAB_H 3 #define MM_SLAB_H 4 /* 5 * Internal slab definitions 6 */ 7 8 /* Reuses the bits in struct page */ 9 struct slab { 10 unsigned long __page_flags; 11 12 #if defined(CONFIG_SLAB) 13 14 union { 15 struct list_head slab_list; 16 struct rcu_head rcu_head; 17 }; 18 struct kmem_cache *slab_cache; 19 void *freelist; /* array of free object indexes */ 20 void *s_mem; /* first object */ 21 unsigned int active; 22 23 #elif defined(CONFIG_SLUB) 24 25 union { 26 struct list_head slab_list; 27 struct rcu_head rcu_head; 28 #ifdef CONFIG_SLUB_CPU_PARTIAL 29 struct { 30 struct slab *next; 31 int slabs; /* Nr of slabs left */ 32 }; 33 #endif 34 }; 35 struct kmem_cache *slab_cache; 36 /* Double-word boundary */ 37 void *freelist; /* first free object */ 38 union { 39 unsigned long counters; 40 struct { 41 unsigned inuse:16; 42 unsigned objects:15; 43 unsigned frozen:1; 44 }; 45 }; 46 unsigned int __unused; 47 48 #elif defined(CONFIG_SLOB) 49 50 struct list_head slab_list; 51 void *__unused_1; 52 void *freelist; /* first free block */ 53 long units; 54 unsigned int __unused_2; 55 56 #else 57 #error "Unexpected slab allocator configured" 58 #endif 59 60 atomic_t __page_refcount; 61 #ifdef CONFIG_MEMCG 62 unsigned long memcg_data; 63 #endif 64 }; 65 66 #define SLAB_MATCH(pg, sl) \ 67 static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl)) 68 SLAB_MATCH(flags, __page_flags); 69 SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */ 70 #ifndef CONFIG_SLOB 71 SLAB_MATCH(rcu_head, rcu_head); 72 #endif 73 SLAB_MATCH(_refcount, __page_refcount); 74 #ifdef CONFIG_MEMCG 75 SLAB_MATCH(memcg_data, memcg_data); 76 #endif 77 #undef SLAB_MATCH 78 static_assert(sizeof(struct slab) <= sizeof(struct page)); 79 80 /** 81 * folio_slab - Converts from folio to slab. 82 * @folio: The folio. 83 * 84 * Currently struct slab is a different representation of a folio where 85 * folio_test_slab() is true. 86 * 87 * Return: The slab which contains this folio. 88 */ 89 #define folio_slab(folio) (_Generic((folio), \ 90 const struct folio *: (const struct slab *)(folio), \ 91 struct folio *: (struct slab *)(folio))) 92 93 /** 94 * slab_folio - The folio allocated for a slab 95 * @slab: The slab. 96 * 97 * Slabs are allocated as folios that contain the individual objects and are 98 * using some fields in the first struct page of the folio - those fields are 99 * now accessed by struct slab. It is occasionally necessary to convert back to 100 * a folio in order to communicate with the rest of the mm. Please use this 101 * helper function instead of casting yourself, as the implementation may change 102 * in the future. 103 */ 104 #define slab_folio(s) (_Generic((s), \ 105 const struct slab *: (const struct folio *)s, \ 106 struct slab *: (struct folio *)s)) 107 108 /** 109 * page_slab - Converts from first struct page to slab. 110 * @p: The first (either head of compound or single) page of slab. 111 * 112 * A temporary wrapper to convert struct page to struct slab in situations where 113 * we know the page is the compound head, or single order-0 page. 114 * 115 * Long-term ideally everything would work with struct slab directly or go 116 * through folio to struct slab. 117 * 118 * Return: The slab which contains this page 119 */ 120 #define page_slab(p) (_Generic((p), \ 121 const struct page *: (const struct slab *)(p), \ 122 struct page *: (struct slab *)(p))) 123 124 /** 125 * slab_page - The first struct page allocated for a slab 126 * @slab: The slab. 127 * 128 * A convenience wrapper for converting slab to the first struct page of the 129 * underlying folio, to communicate with code not yet converted to folio or 130 * struct slab. 131 */ 132 #define slab_page(s) folio_page(slab_folio(s), 0) 133 134 /* 135 * If network-based swap is enabled, sl*b must keep track of whether pages 136 * were allocated from pfmemalloc reserves. 137 */ 138 static inline bool slab_test_pfmemalloc(const struct slab *slab) 139 { 140 return folio_test_active((struct folio *)slab_folio(slab)); 141 } 142 143 static inline void slab_set_pfmemalloc(struct slab *slab) 144 { 145 folio_set_active(slab_folio(slab)); 146 } 147 148 static inline void slab_clear_pfmemalloc(struct slab *slab) 149 { 150 folio_clear_active(slab_folio(slab)); 151 } 152 153 static inline void __slab_clear_pfmemalloc(struct slab *slab) 154 { 155 __folio_clear_active(slab_folio(slab)); 156 } 157 158 static inline void *slab_address(const struct slab *slab) 159 { 160 return folio_address(slab_folio(slab)); 161 } 162 163 static inline int slab_nid(const struct slab *slab) 164 { 165 return folio_nid(slab_folio(slab)); 166 } 167 168 static inline pg_data_t *slab_pgdat(const struct slab *slab) 169 { 170 return folio_pgdat(slab_folio(slab)); 171 } 172 173 static inline struct slab *virt_to_slab(const void *addr) 174 { 175 struct folio *folio = virt_to_folio(addr); 176 177 if (!folio_test_slab(folio)) 178 return NULL; 179 180 return folio_slab(folio); 181 } 182 183 static inline int slab_order(const struct slab *slab) 184 { 185 return folio_order((struct folio *)slab_folio(slab)); 186 } 187 188 static inline size_t slab_size(const struct slab *slab) 189 { 190 return PAGE_SIZE << slab_order(slab); 191 } 192 193 #ifdef CONFIG_SLOB 194 /* 195 * Common fields provided in kmem_cache by all slab allocators 196 * This struct is either used directly by the allocator (SLOB) 197 * or the allocator must include definitions for all fields 198 * provided in kmem_cache_common in their definition of kmem_cache. 199 * 200 * Once we can do anonymous structs (C11 standard) we could put a 201 * anonymous struct definition in these allocators so that the 202 * separate allocations in the kmem_cache structure of SLAB and 203 * SLUB is no longer needed. 204 */ 205 struct kmem_cache { 206 unsigned int object_size;/* The original size of the object */ 207 unsigned int size; /* The aligned/padded/added on size */ 208 unsigned int align; /* Alignment as calculated */ 209 slab_flags_t flags; /* Active flags on the slab */ 210 unsigned int useroffset;/* Usercopy region offset */ 211 unsigned int usersize; /* Usercopy region size */ 212 const char *name; /* Slab name for sysfs */ 213 int refcount; /* Use counter */ 214 void (*ctor)(void *); /* Called on object slot creation */ 215 struct list_head list; /* List of all slab caches on the system */ 216 }; 217 218 #endif /* CONFIG_SLOB */ 219 220 #ifdef CONFIG_SLAB 221 #include <linux/slab_def.h> 222 #endif 223 224 #ifdef CONFIG_SLUB 225 #include <linux/slub_def.h> 226 #endif 227 228 #include <linux/memcontrol.h> 229 #include <linux/fault-inject.h> 230 #include <linux/kasan.h> 231 #include <linux/kmemleak.h> 232 #include <linux/random.h> 233 #include <linux/sched/mm.h> 234 #include <linux/list_lru.h> 235 236 /* 237 * State of the slab allocator. 238 * 239 * This is used to describe the states of the allocator during bootup. 240 * Allocators use this to gradually bootstrap themselves. Most allocators 241 * have the problem that the structures used for managing slab caches are 242 * allocated from slab caches themselves. 243 */ 244 enum slab_state { 245 DOWN, /* No slab functionality yet */ 246 PARTIAL, /* SLUB: kmem_cache_node available */ 247 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */ 248 UP, /* Slab caches usable but not all extras yet */ 249 FULL /* Everything is working */ 250 }; 251 252 extern enum slab_state slab_state; 253 254 /* The slab cache mutex protects the management structures during changes */ 255 extern struct mutex slab_mutex; 256 257 /* The list of all slab caches on the system */ 258 extern struct list_head slab_caches; 259 260 /* The slab cache that manages slab cache information */ 261 extern struct kmem_cache *kmem_cache; 262 263 /* A table of kmalloc cache names and sizes */ 264 extern const struct kmalloc_info_struct { 265 const char *name[NR_KMALLOC_TYPES]; 266 unsigned int size; 267 } kmalloc_info[]; 268 269 #ifndef CONFIG_SLOB 270 /* Kmalloc array related functions */ 271 void setup_kmalloc_cache_index_table(void); 272 void create_kmalloc_caches(slab_flags_t); 273 274 /* Find the kmalloc slab corresponding for a certain size */ 275 struct kmem_cache *kmalloc_slab(size_t, gfp_t); 276 277 void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, 278 int node, size_t orig_size, 279 unsigned long caller); 280 void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller); 281 #endif 282 283 gfp_t kmalloc_fix_flags(gfp_t flags); 284 285 /* Functions provided by the slab allocators */ 286 int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags); 287 288 struct kmem_cache *create_kmalloc_cache(const char *name, unsigned int size, 289 slab_flags_t flags, unsigned int useroffset, 290 unsigned int usersize); 291 extern void create_boot_cache(struct kmem_cache *, const char *name, 292 unsigned int size, slab_flags_t flags, 293 unsigned int useroffset, unsigned int usersize); 294 295 int slab_unmergeable(struct kmem_cache *s); 296 struct kmem_cache *find_mergeable(unsigned size, unsigned align, 297 slab_flags_t flags, const char *name, void (*ctor)(void *)); 298 #ifndef CONFIG_SLOB 299 struct kmem_cache * 300 __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, 301 slab_flags_t flags, void (*ctor)(void *)); 302 303 slab_flags_t kmem_cache_flags(unsigned int object_size, 304 slab_flags_t flags, const char *name); 305 #else 306 static inline struct kmem_cache * 307 __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, 308 slab_flags_t flags, void (*ctor)(void *)) 309 { return NULL; } 310 311 static inline slab_flags_t kmem_cache_flags(unsigned int object_size, 312 slab_flags_t flags, const char *name) 313 { 314 return flags; 315 } 316 #endif 317 318 319 /* Legal flag mask for kmem_cache_create(), for various configurations */ 320 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \ 321 SLAB_CACHE_DMA32 | SLAB_PANIC | \ 322 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS ) 323 324 #if defined(CONFIG_DEBUG_SLAB) 325 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) 326 #elif defined(CONFIG_SLUB_DEBUG) 327 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ 328 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) 329 #else 330 #define SLAB_DEBUG_FLAGS (0) 331 #endif 332 333 #if defined(CONFIG_SLAB) 334 #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ 335 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \ 336 SLAB_ACCOUNT) 337 #elif defined(CONFIG_SLUB) 338 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ 339 SLAB_TEMPORARY | SLAB_ACCOUNT | SLAB_NO_USER_FLAGS) 340 #else 341 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE) 342 #endif 343 344 /* Common flags available with current configuration */ 345 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) 346 347 /* Common flags permitted for kmem_cache_create */ 348 #define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \ 349 SLAB_RED_ZONE | \ 350 SLAB_POISON | \ 351 SLAB_STORE_USER | \ 352 SLAB_TRACE | \ 353 SLAB_CONSISTENCY_CHECKS | \ 354 SLAB_MEM_SPREAD | \ 355 SLAB_NOLEAKTRACE | \ 356 SLAB_RECLAIM_ACCOUNT | \ 357 SLAB_TEMPORARY | \ 358 SLAB_ACCOUNT | \ 359 SLAB_NO_USER_FLAGS) 360 361 bool __kmem_cache_empty(struct kmem_cache *); 362 int __kmem_cache_shutdown(struct kmem_cache *); 363 void __kmem_cache_release(struct kmem_cache *); 364 int __kmem_cache_shrink(struct kmem_cache *); 365 void slab_kmem_cache_release(struct kmem_cache *); 366 367 struct seq_file; 368 struct file; 369 370 struct slabinfo { 371 unsigned long active_objs; 372 unsigned long num_objs; 373 unsigned long active_slabs; 374 unsigned long num_slabs; 375 unsigned long shared_avail; 376 unsigned int limit; 377 unsigned int batchcount; 378 unsigned int shared; 379 unsigned int objects_per_slab; 380 unsigned int cache_order; 381 }; 382 383 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo); 384 void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s); 385 ssize_t slabinfo_write(struct file *file, const char __user *buffer, 386 size_t count, loff_t *ppos); 387 388 static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) 389 { 390 return (s->flags & SLAB_RECLAIM_ACCOUNT) ? 391 NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; 392 } 393 394 #ifdef CONFIG_SLUB_DEBUG 395 #ifdef CONFIG_SLUB_DEBUG_ON 396 DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); 397 #else 398 DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); 399 #endif 400 extern void print_tracking(struct kmem_cache *s, void *object); 401 long validate_slab_cache(struct kmem_cache *s); 402 static inline bool __slub_debug_enabled(void) 403 { 404 return static_branch_unlikely(&slub_debug_enabled); 405 } 406 #else 407 static inline void print_tracking(struct kmem_cache *s, void *object) 408 { 409 } 410 static inline bool __slub_debug_enabled(void) 411 { 412 return false; 413 } 414 #endif 415 416 /* 417 * Returns true if any of the specified slub_debug flags is enabled for the 418 * cache. Use only for flags parsed by setup_slub_debug() as it also enables 419 * the static key. 420 */ 421 static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) 422 { 423 if (IS_ENABLED(CONFIG_SLUB_DEBUG)) 424 VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); 425 if (__slub_debug_enabled()) 426 return s->flags & flags; 427 return false; 428 } 429 430 #ifdef CONFIG_MEMCG_KMEM 431 /* 432 * slab_objcgs - get the object cgroups vector associated with a slab 433 * @slab: a pointer to the slab struct 434 * 435 * Returns a pointer to the object cgroups vector associated with the slab, 436 * or NULL if no such vector has been associated yet. 437 */ 438 static inline struct obj_cgroup **slab_objcgs(struct slab *slab) 439 { 440 unsigned long memcg_data = READ_ONCE(slab->memcg_data); 441 442 VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), 443 slab_page(slab)); 444 VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab)); 445 446 return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); 447 } 448 449 int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, 450 gfp_t gfp, bool new_slab); 451 void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, 452 enum node_stat_item idx, int nr); 453 454 static inline void memcg_free_slab_cgroups(struct slab *slab) 455 { 456 kfree(slab_objcgs(slab)); 457 slab->memcg_data = 0; 458 } 459 460 static inline size_t obj_full_size(struct kmem_cache *s) 461 { 462 /* 463 * For each accounted object there is an extra space which is used 464 * to store obj_cgroup membership. Charge it too. 465 */ 466 return s->size + sizeof(struct obj_cgroup *); 467 } 468 469 /* 470 * Returns false if the allocation should fail. 471 */ 472 static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, 473 struct list_lru *lru, 474 struct obj_cgroup **objcgp, 475 size_t objects, gfp_t flags) 476 { 477 struct obj_cgroup *objcg; 478 479 if (!memcg_kmem_enabled()) 480 return true; 481 482 if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT)) 483 return true; 484 485 objcg = get_obj_cgroup_from_current(); 486 if (!objcg) 487 return true; 488 489 if (lru) { 490 int ret; 491 struct mem_cgroup *memcg; 492 493 memcg = get_mem_cgroup_from_objcg(objcg); 494 ret = memcg_list_lru_alloc(memcg, lru, flags); 495 css_put(&memcg->css); 496 497 if (ret) 498 goto out; 499 } 500 501 if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) 502 goto out; 503 504 *objcgp = objcg; 505 return true; 506 out: 507 obj_cgroup_put(objcg); 508 return false; 509 } 510 511 static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, 512 struct obj_cgroup *objcg, 513 gfp_t flags, size_t size, 514 void **p) 515 { 516 struct slab *slab; 517 unsigned long off; 518 size_t i; 519 520 if (!memcg_kmem_enabled() || !objcg) 521 return; 522 523 for (i = 0; i < size; i++) { 524 if (likely(p[i])) { 525 slab = virt_to_slab(p[i]); 526 527 if (!slab_objcgs(slab) && 528 memcg_alloc_slab_cgroups(slab, s, flags, 529 false)) { 530 obj_cgroup_uncharge(objcg, obj_full_size(s)); 531 continue; 532 } 533 534 off = obj_to_index(s, slab, p[i]); 535 obj_cgroup_get(objcg); 536 slab_objcgs(slab)[off] = objcg; 537 mod_objcg_state(objcg, slab_pgdat(slab), 538 cache_vmstat_idx(s), obj_full_size(s)); 539 } else { 540 obj_cgroup_uncharge(objcg, obj_full_size(s)); 541 } 542 } 543 obj_cgroup_put(objcg); 544 } 545 546 static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, 547 void **p, int objects) 548 { 549 struct obj_cgroup **objcgs; 550 int i; 551 552 if (!memcg_kmem_enabled()) 553 return; 554 555 objcgs = slab_objcgs(slab); 556 if (!objcgs) 557 return; 558 559 for (i = 0; i < objects; i++) { 560 struct obj_cgroup *objcg; 561 unsigned int off; 562 563 off = obj_to_index(s, slab, p[i]); 564 objcg = objcgs[off]; 565 if (!objcg) 566 continue; 567 568 objcgs[off] = NULL; 569 obj_cgroup_uncharge(objcg, obj_full_size(s)); 570 mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s), 571 -obj_full_size(s)); 572 obj_cgroup_put(objcg); 573 } 574 } 575 576 #else /* CONFIG_MEMCG_KMEM */ 577 static inline struct obj_cgroup **slab_objcgs(struct slab *slab) 578 { 579 return NULL; 580 } 581 582 static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr) 583 { 584 return NULL; 585 } 586 587 static inline int memcg_alloc_slab_cgroups(struct slab *slab, 588 struct kmem_cache *s, gfp_t gfp, 589 bool new_slab) 590 { 591 return 0; 592 } 593 594 static inline void memcg_free_slab_cgroups(struct slab *slab) 595 { 596 } 597 598 static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, 599 struct list_lru *lru, 600 struct obj_cgroup **objcgp, 601 size_t objects, gfp_t flags) 602 { 603 return true; 604 } 605 606 static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, 607 struct obj_cgroup *objcg, 608 gfp_t flags, size_t size, 609 void **p) 610 { 611 } 612 613 static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, 614 void **p, int objects) 615 { 616 } 617 #endif /* CONFIG_MEMCG_KMEM */ 618 619 #ifndef CONFIG_SLOB 620 static inline struct kmem_cache *virt_to_cache(const void *obj) 621 { 622 struct slab *slab; 623 624 slab = virt_to_slab(obj); 625 if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n", 626 __func__)) 627 return NULL; 628 return slab->slab_cache; 629 } 630 631 static __always_inline void account_slab(struct slab *slab, int order, 632 struct kmem_cache *s, gfp_t gfp) 633 { 634 if (memcg_kmem_enabled() && (s->flags & SLAB_ACCOUNT)) 635 memcg_alloc_slab_cgroups(slab, s, gfp, true); 636 637 mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), 638 PAGE_SIZE << order); 639 } 640 641 static __always_inline void unaccount_slab(struct slab *slab, int order, 642 struct kmem_cache *s) 643 { 644 if (memcg_kmem_enabled()) 645 memcg_free_slab_cgroups(slab); 646 647 mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), 648 -(PAGE_SIZE << order)); 649 } 650 651 static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) 652 { 653 struct kmem_cache *cachep; 654 655 if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && 656 !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) 657 return s; 658 659 cachep = virt_to_cache(x); 660 if (WARN(cachep && cachep != s, 661 "%s: Wrong slab cache. %s but object is from %s\n", 662 __func__, s->name, cachep->name)) 663 print_tracking(cachep, x); 664 return cachep; 665 } 666 667 void free_large_kmalloc(struct folio *folio, void *object); 668 669 #endif /* CONFIG_SLOB */ 670 671 size_t __ksize(const void *objp); 672 673 static inline size_t slab_ksize(const struct kmem_cache *s) 674 { 675 #ifndef CONFIG_SLUB 676 return s->object_size; 677 678 #else /* CONFIG_SLUB */ 679 # ifdef CONFIG_SLUB_DEBUG 680 /* 681 * Debugging requires use of the padding between object 682 * and whatever may come after it. 683 */ 684 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) 685 return s->object_size; 686 # endif 687 if (s->flags & SLAB_KASAN) 688 return s->object_size; 689 /* 690 * If we have the need to store the freelist pointer 691 * back there or track user information then we can 692 * only use the space before that information. 693 */ 694 if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER)) 695 return s->inuse; 696 /* 697 * Else we can use all the padding etc for the allocation 698 */ 699 return s->size; 700 #endif 701 } 702 703 static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, 704 struct list_lru *lru, 705 struct obj_cgroup **objcgp, 706 size_t size, gfp_t flags) 707 { 708 flags &= gfp_allowed_mask; 709 710 might_alloc(flags); 711 712 if (should_failslab(s, flags)) 713 return NULL; 714 715 if (!memcg_slab_pre_alloc_hook(s, lru, objcgp, size, flags)) 716 return NULL; 717 718 return s; 719 } 720 721 static inline void slab_post_alloc_hook(struct kmem_cache *s, 722 struct obj_cgroup *objcg, gfp_t flags, 723 size_t size, void **p, bool init) 724 { 725 size_t i; 726 727 flags &= gfp_allowed_mask; 728 729 /* 730 * As memory initialization might be integrated into KASAN, 731 * kasan_slab_alloc and initialization memset must be 732 * kept together to avoid discrepancies in behavior. 733 * 734 * As p[i] might get tagged, memset and kmemleak hook come after KASAN. 735 */ 736 for (i = 0; i < size; i++) { 737 p[i] = kasan_slab_alloc(s, p[i], flags, init); 738 if (p[i] && init && !kasan_has_integrated_init()) 739 memset(p[i], 0, s->object_size); 740 kmemleak_alloc_recursive(p[i], s->object_size, 1, 741 s->flags, flags); 742 kmsan_slab_alloc(s, p[i], flags); 743 } 744 745 memcg_slab_post_alloc_hook(s, objcg, flags, size, p); 746 } 747 748 #ifndef CONFIG_SLOB 749 /* 750 * The slab lists for all objects. 751 */ 752 struct kmem_cache_node { 753 spinlock_t list_lock; 754 755 #ifdef CONFIG_SLAB 756 struct list_head slabs_partial; /* partial list first, better asm code */ 757 struct list_head slabs_full; 758 struct list_head slabs_free; 759 unsigned long total_slabs; /* length of all slab lists */ 760 unsigned long free_slabs; /* length of free slab list only */ 761 unsigned long free_objects; 762 unsigned int free_limit; 763 unsigned int colour_next; /* Per-node cache coloring */ 764 struct array_cache *shared; /* shared per node */ 765 struct alien_cache **alien; /* on other nodes */ 766 unsigned long next_reap; /* updated without locking */ 767 int free_touched; /* updated without locking */ 768 #endif 769 770 #ifdef CONFIG_SLUB 771 unsigned long nr_partial; 772 struct list_head partial; 773 #ifdef CONFIG_SLUB_DEBUG 774 atomic_long_t nr_slabs; 775 atomic_long_t total_objects; 776 struct list_head full; 777 #endif 778 #endif 779 780 }; 781 782 static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) 783 { 784 return s->node[node]; 785 } 786 787 /* 788 * Iterator over all nodes. The body will be executed for each node that has 789 * a kmem_cache_node structure allocated (which is true for all online nodes) 790 */ 791 #define for_each_kmem_cache_node(__s, __node, __n) \ 792 for (__node = 0; __node < nr_node_ids; __node++) \ 793 if ((__n = get_node(__s, __node))) 794 795 #endif 796 797 #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) 798 void dump_unreclaimable_slab(void); 799 #else 800 static inline void dump_unreclaimable_slab(void) 801 { 802 } 803 #endif 804 805 void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); 806 807 #ifdef CONFIG_SLAB_FREELIST_RANDOM 808 int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, 809 gfp_t gfp); 810 void cache_random_seq_destroy(struct kmem_cache *cachep); 811 #else 812 static inline int cache_random_seq_create(struct kmem_cache *cachep, 813 unsigned int count, gfp_t gfp) 814 { 815 return 0; 816 } 817 static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } 818 #endif /* CONFIG_SLAB_FREELIST_RANDOM */ 819 820 static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) 821 { 822 if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, 823 &init_on_alloc)) { 824 if (c->ctor) 825 return false; 826 if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) 827 return flags & __GFP_ZERO; 828 return true; 829 } 830 return flags & __GFP_ZERO; 831 } 832 833 static inline bool slab_want_init_on_free(struct kmem_cache *c) 834 { 835 if (static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON, 836 &init_on_free)) 837 return !(c->ctor || 838 (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))); 839 return false; 840 } 841 842 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) 843 void debugfs_slab_release(struct kmem_cache *); 844 #else 845 static inline void debugfs_slab_release(struct kmem_cache *s) { } 846 #endif 847 848 #ifdef CONFIG_PRINTK 849 #define KS_ADDRS_COUNT 16 850 struct kmem_obj_info { 851 void *kp_ptr; 852 struct slab *kp_slab; 853 void *kp_objp; 854 unsigned long kp_data_offset; 855 struct kmem_cache *kp_slab_cache; 856 void *kp_ret; 857 void *kp_stack[KS_ADDRS_COUNT]; 858 void *kp_free_stack[KS_ADDRS_COUNT]; 859 }; 860 void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab); 861 #endif 862 863 #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR 864 void __check_heap_object(const void *ptr, unsigned long n, 865 const struct slab *slab, bool to_user); 866 #else 867 static inline 868 void __check_heap_object(const void *ptr, unsigned long n, 869 const struct slab *slab, bool to_user) 870 { 871 } 872 #endif 873 874 #endif /* MM_SLAB_H */ 875