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> 234 235 /* 236 * State of the slab allocator. 237 * 238 * This is used to describe the states of the allocator during bootup. 239 * Allocators use this to gradually bootstrap themselves. Most allocators 240 * have the problem that the structures used for managing slab caches are 241 * allocated from slab caches themselves. 242 */ 243 enum slab_state { 244 DOWN, /* No slab functionality yet */ 245 PARTIAL, /* SLUB: kmem_cache_node available */ 246 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */ 247 UP, /* Slab caches usable but not all extras yet */ 248 FULL /* Everything is working */ 249 }; 250 251 extern enum slab_state slab_state; 252 253 /* The slab cache mutex protects the management structures during changes */ 254 extern struct mutex slab_mutex; 255 256 /* The list of all slab caches on the system */ 257 extern struct list_head slab_caches; 258 259 /* The slab cache that manages slab cache information */ 260 extern struct kmem_cache *kmem_cache; 261 262 /* A table of kmalloc cache names and sizes */ 263 extern const struct kmalloc_info_struct { 264 const char *name[NR_KMALLOC_TYPES]; 265 unsigned int size; 266 } kmalloc_info[]; 267 268 #ifndef CONFIG_SLOB 269 /* Kmalloc array related functions */ 270 void setup_kmalloc_cache_index_table(void); 271 void create_kmalloc_caches(slab_flags_t); 272 273 /* Find the kmalloc slab corresponding for a certain size */ 274 struct kmem_cache *kmalloc_slab(size_t, gfp_t); 275 #endif 276 277 gfp_t kmalloc_fix_flags(gfp_t flags); 278 279 /* Functions provided by the slab allocators */ 280 int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags); 281 282 struct kmem_cache *create_kmalloc_cache(const char *name, unsigned int size, 283 slab_flags_t flags, unsigned int useroffset, 284 unsigned int usersize); 285 extern void create_boot_cache(struct kmem_cache *, const char *name, 286 unsigned int size, slab_flags_t flags, 287 unsigned int useroffset, unsigned int usersize); 288 289 int slab_unmergeable(struct kmem_cache *s); 290 struct kmem_cache *find_mergeable(unsigned size, unsigned align, 291 slab_flags_t flags, const char *name, void (*ctor)(void *)); 292 #ifndef CONFIG_SLOB 293 struct kmem_cache * 294 __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, 295 slab_flags_t flags, void (*ctor)(void *)); 296 297 slab_flags_t kmem_cache_flags(unsigned int object_size, 298 slab_flags_t flags, const char *name); 299 #else 300 static inline struct kmem_cache * 301 __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, 302 slab_flags_t flags, void (*ctor)(void *)) 303 { return NULL; } 304 305 static inline slab_flags_t kmem_cache_flags(unsigned int object_size, 306 slab_flags_t flags, const char *name) 307 { 308 return flags; 309 } 310 #endif 311 312 313 /* Legal flag mask for kmem_cache_create(), for various configurations */ 314 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \ 315 SLAB_CACHE_DMA32 | SLAB_PANIC | \ 316 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS ) 317 318 #if defined(CONFIG_DEBUG_SLAB) 319 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) 320 #elif defined(CONFIG_SLUB_DEBUG) 321 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ 322 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) 323 #else 324 #define SLAB_DEBUG_FLAGS (0) 325 #endif 326 327 #if defined(CONFIG_SLAB) 328 #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ 329 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \ 330 SLAB_ACCOUNT) 331 #elif defined(CONFIG_SLUB) 332 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ 333 SLAB_TEMPORARY | SLAB_ACCOUNT) 334 #else 335 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE) 336 #endif 337 338 /* Common flags available with current configuration */ 339 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) 340 341 /* Common flags permitted for kmem_cache_create */ 342 #define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \ 343 SLAB_RED_ZONE | \ 344 SLAB_POISON | \ 345 SLAB_STORE_USER | \ 346 SLAB_TRACE | \ 347 SLAB_CONSISTENCY_CHECKS | \ 348 SLAB_MEM_SPREAD | \ 349 SLAB_NOLEAKTRACE | \ 350 SLAB_RECLAIM_ACCOUNT | \ 351 SLAB_TEMPORARY | \ 352 SLAB_ACCOUNT) 353 354 bool __kmem_cache_empty(struct kmem_cache *); 355 int __kmem_cache_shutdown(struct kmem_cache *); 356 void __kmem_cache_release(struct kmem_cache *); 357 int __kmem_cache_shrink(struct kmem_cache *); 358 void slab_kmem_cache_release(struct kmem_cache *); 359 360 struct seq_file; 361 struct file; 362 363 struct slabinfo { 364 unsigned long active_objs; 365 unsigned long num_objs; 366 unsigned long active_slabs; 367 unsigned long num_slabs; 368 unsigned long shared_avail; 369 unsigned int limit; 370 unsigned int batchcount; 371 unsigned int shared; 372 unsigned int objects_per_slab; 373 unsigned int cache_order; 374 }; 375 376 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo); 377 void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s); 378 ssize_t slabinfo_write(struct file *file, const char __user *buffer, 379 size_t count, loff_t *ppos); 380 381 /* 382 * Generic implementation of bulk operations 383 * These are useful for situations in which the allocator cannot 384 * perform optimizations. In that case segments of the object listed 385 * may be allocated or freed using these operations. 386 */ 387 void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **); 388 int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **); 389 390 static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) 391 { 392 return (s->flags & SLAB_RECLAIM_ACCOUNT) ? 393 NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; 394 } 395 396 #ifdef CONFIG_SLUB_DEBUG 397 #ifdef CONFIG_SLUB_DEBUG_ON 398 DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); 399 #else 400 DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); 401 #endif 402 extern void print_tracking(struct kmem_cache *s, void *object); 403 long validate_slab_cache(struct kmem_cache *s); 404 static inline bool __slub_debug_enabled(void) 405 { 406 return static_branch_unlikely(&slub_debug_enabled); 407 } 408 #else 409 static inline void print_tracking(struct kmem_cache *s, void *object) 410 { 411 } 412 static inline bool __slub_debug_enabled(void) 413 { 414 return false; 415 } 416 #endif 417 418 /* 419 * Returns true if any of the specified slub_debug flags is enabled for the 420 * cache. Use only for flags parsed by setup_slub_debug() as it also enables 421 * the static key. 422 */ 423 static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) 424 { 425 if (IS_ENABLED(CONFIG_SLUB_DEBUG)) 426 VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); 427 if (__slub_debug_enabled()) 428 return s->flags & flags; 429 return false; 430 } 431 432 #ifdef CONFIG_MEMCG_KMEM 433 /* 434 * slab_objcgs - get the object cgroups vector associated with a slab 435 * @slab: a pointer to the slab struct 436 * 437 * Returns a pointer to the object cgroups vector associated with the slab, 438 * or NULL if no such vector has been associated yet. 439 */ 440 static inline struct obj_cgroup **slab_objcgs(struct slab *slab) 441 { 442 unsigned long memcg_data = READ_ONCE(slab->memcg_data); 443 444 VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), 445 slab_page(slab)); 446 VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab)); 447 448 return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); 449 } 450 451 int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, 452 gfp_t gfp, bool new_slab); 453 void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, 454 enum node_stat_item idx, int nr); 455 456 static inline void memcg_free_slab_cgroups(struct slab *slab) 457 { 458 kfree(slab_objcgs(slab)); 459 slab->memcg_data = 0; 460 } 461 462 static inline size_t obj_full_size(struct kmem_cache *s) 463 { 464 /* 465 * For each accounted object there is an extra space which is used 466 * to store obj_cgroup membership. Charge it too. 467 */ 468 return s->size + sizeof(struct obj_cgroup *); 469 } 470 471 /* 472 * Returns false if the allocation should fail. 473 */ 474 static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, 475 struct obj_cgroup **objcgp, 476 size_t objects, gfp_t flags) 477 { 478 struct obj_cgroup *objcg; 479 480 if (!memcg_kmem_enabled()) 481 return true; 482 483 if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT)) 484 return true; 485 486 objcg = get_obj_cgroup_from_current(); 487 if (!objcg) 488 return true; 489 490 if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) { 491 obj_cgroup_put(objcg); 492 return false; 493 } 494 495 *objcgp = objcg; 496 return true; 497 } 498 499 static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, 500 struct obj_cgroup *objcg, 501 gfp_t flags, size_t size, 502 void **p) 503 { 504 struct slab *slab; 505 unsigned long off; 506 size_t i; 507 508 if (!memcg_kmem_enabled() || !objcg) 509 return; 510 511 for (i = 0; i < size; i++) { 512 if (likely(p[i])) { 513 slab = virt_to_slab(p[i]); 514 515 if (!slab_objcgs(slab) && 516 memcg_alloc_slab_cgroups(slab, s, flags, 517 false)) { 518 obj_cgroup_uncharge(objcg, obj_full_size(s)); 519 continue; 520 } 521 522 off = obj_to_index(s, slab, p[i]); 523 obj_cgroup_get(objcg); 524 slab_objcgs(slab)[off] = objcg; 525 mod_objcg_state(objcg, slab_pgdat(slab), 526 cache_vmstat_idx(s), obj_full_size(s)); 527 } else { 528 obj_cgroup_uncharge(objcg, obj_full_size(s)); 529 } 530 } 531 obj_cgroup_put(objcg); 532 } 533 534 static inline void memcg_slab_free_hook(struct kmem_cache *s_orig, 535 void **p, int objects) 536 { 537 struct kmem_cache *s; 538 struct obj_cgroup **objcgs; 539 struct obj_cgroup *objcg; 540 struct slab *slab; 541 unsigned int off; 542 int i; 543 544 if (!memcg_kmem_enabled()) 545 return; 546 547 for (i = 0; i < objects; i++) { 548 if (unlikely(!p[i])) 549 continue; 550 551 slab = virt_to_slab(p[i]); 552 /* we could be given a kmalloc_large() object, skip those */ 553 if (!slab) 554 continue; 555 556 objcgs = slab_objcgs(slab); 557 if (!objcgs) 558 continue; 559 560 if (!s_orig) 561 s = slab->slab_cache; 562 else 563 s = s_orig; 564 565 off = obj_to_index(s, slab, p[i]); 566 objcg = objcgs[off]; 567 if (!objcg) 568 continue; 569 570 objcgs[off] = NULL; 571 obj_cgroup_uncharge(objcg, obj_full_size(s)); 572 mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s), 573 -obj_full_size(s)); 574 obj_cgroup_put(objcg); 575 } 576 } 577 578 #else /* CONFIG_MEMCG_KMEM */ 579 static inline struct obj_cgroup **slab_objcgs(struct slab *slab) 580 { 581 return NULL; 582 } 583 584 static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr) 585 { 586 return NULL; 587 } 588 589 static inline int memcg_alloc_slab_cgroups(struct slab *slab, 590 struct kmem_cache *s, gfp_t gfp, 591 bool new_slab) 592 { 593 return 0; 594 } 595 596 static inline void memcg_free_slab_cgroups(struct slab *slab) 597 { 598 } 599 600 static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, 601 struct obj_cgroup **objcgp, 602 size_t objects, gfp_t flags) 603 { 604 return true; 605 } 606 607 static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, 608 struct obj_cgroup *objcg, 609 gfp_t flags, size_t size, 610 void **p) 611 { 612 } 613 614 static inline void memcg_slab_free_hook(struct kmem_cache *s, 615 void **p, int objects) 616 { 617 } 618 #endif /* CONFIG_MEMCG_KMEM */ 619 620 #ifndef CONFIG_SLOB 621 static inline struct kmem_cache *virt_to_cache(const void *obj) 622 { 623 struct slab *slab; 624 625 slab = virt_to_slab(obj); 626 if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n", 627 __func__)) 628 return NULL; 629 return slab->slab_cache; 630 } 631 632 static __always_inline void account_slab(struct slab *slab, int order, 633 struct kmem_cache *s, gfp_t gfp) 634 { 635 if (memcg_kmem_enabled() && (s->flags & SLAB_ACCOUNT)) 636 memcg_alloc_slab_cgroups(slab, s, gfp, true); 637 638 mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), 639 PAGE_SIZE << order); 640 } 641 642 static __always_inline void unaccount_slab(struct slab *slab, int order, 643 struct kmem_cache *s) 644 { 645 if (memcg_kmem_enabled()) 646 memcg_free_slab_cgroups(slab); 647 648 mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s), 649 -(PAGE_SIZE << order)); 650 } 651 652 static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) 653 { 654 struct kmem_cache *cachep; 655 656 if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && 657 !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) 658 return s; 659 660 cachep = virt_to_cache(x); 661 if (WARN(cachep && cachep != s, 662 "%s: Wrong slab cache. %s but object is from %s\n", 663 __func__, s->name, cachep->name)) 664 print_tracking(cachep, x); 665 return cachep; 666 } 667 #endif /* CONFIG_SLOB */ 668 669 static inline size_t slab_ksize(const struct kmem_cache *s) 670 { 671 #ifndef CONFIG_SLUB 672 return s->object_size; 673 674 #else /* CONFIG_SLUB */ 675 # ifdef CONFIG_SLUB_DEBUG 676 /* 677 * Debugging requires use of the padding between object 678 * and whatever may come after it. 679 */ 680 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) 681 return s->object_size; 682 # endif 683 if (s->flags & SLAB_KASAN) 684 return s->object_size; 685 /* 686 * If we have the need to store the freelist pointer 687 * back there or track user information then we can 688 * only use the space before that information. 689 */ 690 if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER)) 691 return s->inuse; 692 /* 693 * Else we can use all the padding etc for the allocation 694 */ 695 return s->size; 696 #endif 697 } 698 699 static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, 700 struct obj_cgroup **objcgp, 701 size_t size, gfp_t flags) 702 { 703 flags &= gfp_allowed_mask; 704 705 might_alloc(flags); 706 707 if (should_failslab(s, flags)) 708 return NULL; 709 710 if (!memcg_slab_pre_alloc_hook(s, objcgp, size, flags)) 711 return NULL; 712 713 return s; 714 } 715 716 static inline void slab_post_alloc_hook(struct kmem_cache *s, 717 struct obj_cgroup *objcg, gfp_t flags, 718 size_t size, void **p, bool init) 719 { 720 size_t i; 721 722 flags &= gfp_allowed_mask; 723 724 /* 725 * As memory initialization might be integrated into KASAN, 726 * kasan_slab_alloc and initialization memset must be 727 * kept together to avoid discrepancies in behavior. 728 * 729 * As p[i] might get tagged, memset and kmemleak hook come after KASAN. 730 */ 731 for (i = 0; i < size; i++) { 732 p[i] = kasan_slab_alloc(s, p[i], flags, init); 733 if (p[i] && init && !kasan_has_integrated_init()) 734 memset(p[i], 0, s->object_size); 735 kmemleak_alloc_recursive(p[i], s->object_size, 1, 736 s->flags, flags); 737 } 738 739 memcg_slab_post_alloc_hook(s, objcg, flags, size, p); 740 } 741 742 #ifndef CONFIG_SLOB 743 /* 744 * The slab lists for all objects. 745 */ 746 struct kmem_cache_node { 747 spinlock_t list_lock; 748 749 #ifdef CONFIG_SLAB 750 struct list_head slabs_partial; /* partial list first, better asm code */ 751 struct list_head slabs_full; 752 struct list_head slabs_free; 753 unsigned long total_slabs; /* length of all slab lists */ 754 unsigned long free_slabs; /* length of free slab list only */ 755 unsigned long free_objects; 756 unsigned int free_limit; 757 unsigned int colour_next; /* Per-node cache coloring */ 758 struct array_cache *shared; /* shared per node */ 759 struct alien_cache **alien; /* on other nodes */ 760 unsigned long next_reap; /* updated without locking */ 761 int free_touched; /* updated without locking */ 762 #endif 763 764 #ifdef CONFIG_SLUB 765 unsigned long nr_partial; 766 struct list_head partial; 767 #ifdef CONFIG_SLUB_DEBUG 768 atomic_long_t nr_slabs; 769 atomic_long_t total_objects; 770 struct list_head full; 771 #endif 772 #endif 773 774 }; 775 776 static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) 777 { 778 return s->node[node]; 779 } 780 781 /* 782 * Iterator over all nodes. The body will be executed for each node that has 783 * a kmem_cache_node structure allocated (which is true for all online nodes) 784 */ 785 #define for_each_kmem_cache_node(__s, __node, __n) \ 786 for (__node = 0; __node < nr_node_ids; __node++) \ 787 if ((__n = get_node(__s, __node))) 788 789 #endif 790 791 #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG) 792 void dump_unreclaimable_slab(void); 793 #else 794 static inline void dump_unreclaimable_slab(void) 795 { 796 } 797 #endif 798 799 void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); 800 801 #ifdef CONFIG_SLAB_FREELIST_RANDOM 802 int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, 803 gfp_t gfp); 804 void cache_random_seq_destroy(struct kmem_cache *cachep); 805 #else 806 static inline int cache_random_seq_create(struct kmem_cache *cachep, 807 unsigned int count, gfp_t gfp) 808 { 809 return 0; 810 } 811 static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } 812 #endif /* CONFIG_SLAB_FREELIST_RANDOM */ 813 814 static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) 815 { 816 if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, 817 &init_on_alloc)) { 818 if (c->ctor) 819 return false; 820 if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) 821 return flags & __GFP_ZERO; 822 return true; 823 } 824 return flags & __GFP_ZERO; 825 } 826 827 static inline bool slab_want_init_on_free(struct kmem_cache *c) 828 { 829 if (static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON, 830 &init_on_free)) 831 return !(c->ctor || 832 (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))); 833 return false; 834 } 835 836 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) 837 void debugfs_slab_release(struct kmem_cache *); 838 #else 839 static inline void debugfs_slab_release(struct kmem_cache *s) { } 840 #endif 841 842 #ifdef CONFIG_PRINTK 843 #define KS_ADDRS_COUNT 16 844 struct kmem_obj_info { 845 void *kp_ptr; 846 struct slab *kp_slab; 847 void *kp_objp; 848 unsigned long kp_data_offset; 849 struct kmem_cache *kp_slab_cache; 850 void *kp_ret; 851 void *kp_stack[KS_ADDRS_COUNT]; 852 void *kp_free_stack[KS_ADDRS_COUNT]; 853 }; 854 void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab); 855 #endif 856 857 #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR 858 void __check_heap_object(const void *ptr, unsigned long n, 859 const struct slab *slab, bool to_user); 860 #else 861 static inline 862 void __check_heap_object(const void *ptr, unsigned long n, 863 const struct slab *slab, bool to_user) 864 { 865 } 866 #endif 867 868 #endif /* MM_SLAB_H */ 869