| 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * SLOB Allocator: Simple List Of Blocks |
| 4 | * |
| 5 | * Matt Mackall <mpm@selenic.com> 12/30/03 |
| 6 | * |
| 7 | * NUMA support by Paul Mundt, 2007. |
| 8 | * |
| 9 | * How SLOB works: |
| 10 | * |
| 11 | * The core of SLOB is a traditional K&R style heap allocator, with |
| 12 | * support for returning aligned objects. The granularity of this |
| 13 | * allocator is as little as 2 bytes, however typically most architectures |
| 14 | * will require 4 bytes on 32-bit and 8 bytes on 64-bit. |
| 15 | * |
| 16 | * The slob heap is a set of linked list of pages from alloc_pages(), |
| 17 | * and within each page, there is a singly-linked list of free blocks |
| 18 | * (slob_t). The heap is grown on demand. To reduce fragmentation, |
| 19 | * heap pages are segregated into three lists, with objects less than |
| 20 | * 256 bytes, objects less than 1024 bytes, and all other objects. |
| 21 | * |
| 22 | * Allocation from heap involves first searching for a page with |
| 23 | * sufficient free blocks (using a next-fit-like approach) followed by |
| 24 | * a first-fit scan of the page. Deallocation inserts objects back |
| 25 | * into the free list in address order, so this is effectively an |
| 26 | * address-ordered first fit. |
| 27 | * |
| 28 | * Above this is an implementation of kmalloc/kfree. Blocks returned |
| 29 | * from kmalloc are prepended with a 4-byte header with the kmalloc size. |
| 30 | * If kmalloc is asked for objects of PAGE_SIZE or larger, it calls |
| 31 | * alloc_pages() directly, allocating compound pages so the page order |
| 32 | * does not have to be separately tracked. |
| 33 | * These objects are detected in kfree() because PageSlab() |
| 34 | * is false for them. |
| 35 | * |
| 36 | * SLAB is emulated on top of SLOB by simply calling constructors and |
| 37 | * destructors for every SLAB allocation. Objects are returned with the |
| 38 | * 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which |
| 39 | * case the low-level allocator will fragment blocks to create the proper |
| 40 | * alignment. Again, objects of page-size or greater are allocated by |
| 41 | * calling alloc_pages(). As SLAB objects know their size, no separate |
| 42 | * size bookkeeping is necessary and there is essentially no allocation |
| 43 | * space overhead, and compound pages aren't needed for multi-page |
| 44 | * allocations. |
| 45 | * |
| 46 | * NUMA support in SLOB is fairly simplistic, pushing most of the real |
| 47 | * logic down to the page allocator, and simply doing the node accounting |
| 48 | * on the upper levels. In the event that a node id is explicitly |
| 49 | * provided, __alloc_pages_node() with the specified node id is used |
| 50 | * instead. The common case (or when the node id isn't explicitly provided) |
| 51 | * will default to the current node, as per numa_node_id(). |
| 52 | * |
| 53 | * Node aware pages are still inserted in to the global freelist, and |
| 54 | * these are scanned for by matching against the node id encoded in the |
| 55 | * page flags. As a result, block allocations that can be satisfied from |
| 56 | * the freelist will only be done so on pages residing on the same node, |
| 57 | * in order to prevent random node placement. |
| 58 | */ |
| 59 | |
| 60 | #include <linux/kernel.h> |
| 61 | #include <linux/slab.h> |
| 62 | |
| 63 | #include <linux/mm.h> |
| 64 | #include <linux/swap.h> /* struct reclaim_state */ |
| 65 | #include <linux/cache.h> |
| 66 | #include <linux/init.h> |
| 67 | #include <linux/export.h> |
| 68 | #include <linux/rcupdate.h> |
| 69 | #include <linux/list.h> |
| 70 | #include <linux/kmemleak.h> |
| 71 | |
| 72 | #include <trace/events/kmem.h> |
| 73 | |
| 74 | #include <linux/atomic.h> |
| 75 | |
| 76 | #include "slab.h" |
| 77 | /* |
| 78 | * slob_block has a field 'units', which indicates size of block if +ve, |
| 79 | * or offset of next block if -ve (in SLOB_UNITs). |
| 80 | * |
| 81 | * Free blocks of size 1 unit simply contain the offset of the next block. |
| 82 | * Those with larger size contain their size in the first SLOB_UNIT of |
| 83 | * memory, and the offset of the next free block in the second SLOB_UNIT. |
| 84 | */ |
| 85 | #if PAGE_SIZE <= (32767 * 2) |
| 86 | typedef s16 slobidx_t; |
| 87 | #else |
| 88 | typedef s32 slobidx_t; |
| 89 | #endif |
| 90 | |
| 91 | struct slob_block { |
| 92 | slobidx_t units; |
| 93 | }; |
| 94 | typedef struct slob_block slob_t; |
| 95 | |
| 96 | /* |
| 97 | * All partially free slob pages go on these lists. |
| 98 | */ |
| 99 | #define SLOB_BREAK1 256 |
| 100 | #define SLOB_BREAK2 1024 |
| 101 | static LIST_HEAD(free_slob_small); |
| 102 | static LIST_HEAD(free_slob_medium); |
| 103 | static LIST_HEAD(free_slob_large); |
| 104 | |
| 105 | /* |
| 106 | * slob_page_free: true for pages on free_slob_pages list. |
| 107 | */ |
| 108 | static inline int slob_page_free(struct page *sp) |
| 109 | { |
| 110 | return PageSlobFree(sp); |
| 111 | } |
| 112 | |
| 113 | static void set_slob_page_free(struct page *sp, struct list_head *list) |
| 114 | { |
| 115 | list_add(&sp->slab_list, list); |
| 116 | __SetPageSlobFree(sp); |
| 117 | } |
| 118 | |
| 119 | static inline void clear_slob_page_free(struct page *sp) |
| 120 | { |
| 121 | list_del(&sp->slab_list); |
| 122 | __ClearPageSlobFree(sp); |
| 123 | } |
| 124 | |
| 125 | #define SLOB_UNIT sizeof(slob_t) |
| 126 | #define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT) |
| 127 | |
| 128 | /* |
| 129 | * struct slob_rcu is inserted at the tail of allocated slob blocks, which |
| 130 | * were created with a SLAB_TYPESAFE_BY_RCU slab. slob_rcu is used to free |
| 131 | * the block using call_rcu. |
| 132 | */ |
| 133 | struct slob_rcu { |
| 134 | struct rcu_head head; |
| 135 | int size; |
| 136 | }; |
| 137 | |
| 138 | /* |
| 139 | * slob_lock protects all slob allocator structures. |
| 140 | */ |
| 141 | static DEFINE_SPINLOCK(slob_lock); |
| 142 | |
| 143 | /* |
| 144 | * Encode the given size and next info into a free slob block s. |
| 145 | */ |
| 146 | static void set_slob(slob_t *s, slobidx_t size, slob_t *next) |
| 147 | { |
| 148 | slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); |
| 149 | slobidx_t offset = next - base; |
| 150 | |
| 151 | if (size > 1) { |
| 152 | s[0].units = size; |
| 153 | s[1].units = offset; |
| 154 | } else |
| 155 | s[0].units = -offset; |
| 156 | } |
| 157 | |
| 158 | /* |
| 159 | * Return the size of a slob block. |
| 160 | */ |
| 161 | static slobidx_t slob_units(slob_t *s) |
| 162 | { |
| 163 | if (s->units > 0) |
| 164 | return s->units; |
| 165 | return 1; |
| 166 | } |
| 167 | |
| 168 | /* |
| 169 | * Return the next free slob block pointer after this one. |
| 170 | */ |
| 171 | static slob_t *slob_next(slob_t *s) |
| 172 | { |
| 173 | slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); |
| 174 | slobidx_t next; |
| 175 | |
| 176 | if (s[0].units < 0) |
| 177 | next = -s[0].units; |
| 178 | else |
| 179 | next = s[1].units; |
| 180 | return base+next; |
| 181 | } |
| 182 | |
| 183 | /* |
| 184 | * Returns true if s is the last free block in its page. |
| 185 | */ |
| 186 | static int slob_last(slob_t *s) |
| 187 | { |
| 188 | return !((unsigned long)slob_next(s) & ~PAGE_MASK); |
| 189 | } |
| 190 | |
| 191 | static void *slob_new_pages(gfp_t gfp, int order, int node) |
| 192 | { |
| 193 | void *page; |
| 194 | |
| 195 | #ifdef CONFIG_NUMA |
| 196 | if (node != NUMA_NO_NODE) |
| 197 | page = __alloc_pages_node(node, gfp, order); |
| 198 | else |
| 199 | #endif |
| 200 | page = alloc_pages(gfp, order); |
| 201 | |
| 202 | if (!page) |
| 203 | return NULL; |
| 204 | |
| 205 | return page_address(page); |
| 206 | } |
| 207 | |
| 208 | static void slob_free_pages(void *b, int order) |
| 209 | { |
| 210 | if (current->reclaim_state) |
| 211 | current->reclaim_state->reclaimed_slab += 1 << order; |
| 212 | free_pages((unsigned long)b, order); |
| 213 | } |
| 214 | |
| 215 | /* |
| 216 | * slob_page_alloc() - Allocate a slob block within a given slob_page sp. |
| 217 | * @sp: Page to look in. |
| 218 | * @size: Size of the allocation. |
| 219 | * @align: Allocation alignment. |
| 220 | * @page_removed_from_list: Return parameter. |
| 221 | * |
| 222 | * Tries to find a chunk of memory at least @size bytes big within @page. |
| 223 | * |
| 224 | * Return: Pointer to memory if allocated, %NULL otherwise. If the |
| 225 | * allocation fills up @page then the page is removed from the |
| 226 | * freelist, in this case @page_removed_from_list will be set to |
| 227 | * true (set to false otherwise). |
| 228 | */ |
| 229 | static void *slob_page_alloc(struct page *sp, size_t size, int align, |
| 230 | bool *page_removed_from_list) |
| 231 | { |
| 232 | slob_t *prev, *cur, *aligned = NULL; |
| 233 | int delta = 0, units = SLOB_UNITS(size); |
| 234 | |
| 235 | *page_removed_from_list = false; |
| 236 | for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) { |
| 237 | slobidx_t avail = slob_units(cur); |
| 238 | |
| 239 | if (align) { |
| 240 | aligned = (slob_t *)ALIGN((unsigned long)cur, align); |
| 241 | delta = aligned - cur; |
| 242 | } |
| 243 | if (avail >= units + delta) { /* room enough? */ |
| 244 | slob_t *next; |
| 245 | |
| 246 | if (delta) { /* need to fragment head to align? */ |
| 247 | next = slob_next(cur); |
| 248 | set_slob(aligned, avail - delta, next); |
| 249 | set_slob(cur, delta, aligned); |
| 250 | prev = cur; |
| 251 | cur = aligned; |
| 252 | avail = slob_units(cur); |
| 253 | } |
| 254 | |
| 255 | next = slob_next(cur); |
| 256 | if (avail == units) { /* exact fit? unlink. */ |
| 257 | if (prev) |
| 258 | set_slob(prev, slob_units(prev), next); |
| 259 | else |
| 260 | sp->freelist = next; |
| 261 | } else { /* fragment */ |
| 262 | if (prev) |
| 263 | set_slob(prev, slob_units(prev), cur + units); |
| 264 | else |
| 265 | sp->freelist = cur + units; |
| 266 | set_slob(cur + units, avail - units, next); |
| 267 | } |
| 268 | |
| 269 | sp->units -= units; |
| 270 | if (!sp->units) { |
| 271 | clear_slob_page_free(sp); |
| 272 | *page_removed_from_list = true; |
| 273 | } |
| 274 | return cur; |
| 275 | } |
| 276 | if (slob_last(cur)) |
| 277 | return NULL; |
| 278 | } |
| 279 | } |
| 280 | |
| 281 | /* |
| 282 | * slob_alloc: entry point into the slob allocator. |
| 283 | */ |
| 284 | static void *slob_alloc(size_t size, gfp_t gfp, int align, int node) |
| 285 | { |
| 286 | struct page *sp; |
| 287 | struct list_head *slob_list; |
| 288 | slob_t *b = NULL; |
| 289 | unsigned long flags; |
| 290 | bool _unused; |
| 291 | |
| 292 | if (size < SLOB_BREAK1) |
| 293 | slob_list = &free_slob_small; |
| 294 | else if (size < SLOB_BREAK2) |
| 295 | slob_list = &free_slob_medium; |
| 296 | else |
| 297 | slob_list = &free_slob_large; |
| 298 | |
| 299 | spin_lock_irqsave(&slob_lock, flags); |
| 300 | /* Iterate through each partially free page, try to find room */ |
| 301 | list_for_each_entry(sp, slob_list, slab_list) { |
| 302 | bool page_removed_from_list = false; |
| 303 | #ifdef CONFIG_NUMA |
| 304 | /* |
| 305 | * If there's a node specification, search for a partial |
| 306 | * page with a matching node id in the freelist. |
| 307 | */ |
| 308 | if (node != NUMA_NO_NODE && page_to_nid(sp) != node) |
| 309 | continue; |
| 310 | #endif |
| 311 | /* Enough room on this page? */ |
| 312 | if (sp->units < SLOB_UNITS(size)) |
| 313 | continue; |
| 314 | |
| 315 | b = slob_page_alloc(sp, size, align, &page_removed_from_list); |
| 316 | if (!b) |
| 317 | continue; |
| 318 | |
| 319 | /* |
| 320 | * If slob_page_alloc() removed sp from the list then we |
| 321 | * cannot call list functions on sp. If so allocation |
| 322 | * did not fragment the page anyway so optimisation is |
| 323 | * unnecessary. |
| 324 | */ |
| 325 | if (!page_removed_from_list) { |
| 326 | /* |
| 327 | * Improve fragment distribution and reduce our average |
| 328 | * search time by starting our next search here. (see |
| 329 | * Knuth vol 1, sec 2.5, pg 449) |
| 330 | */ |
| 331 | if (!list_is_first(&sp->slab_list, slob_list)) |
| 332 | list_rotate_to_front(&sp->slab_list, slob_list); |
| 333 | } |
| 334 | break; |
| 335 | } |
| 336 | spin_unlock_irqrestore(&slob_lock, flags); |
| 337 | |
| 338 | /* Not enough space: must allocate a new page */ |
| 339 | if (!b) { |
| 340 | b = slob_new_pages(gfp & ~__GFP_ZERO, 0, node); |
| 341 | if (!b) |
| 342 | return NULL; |
| 343 | sp = virt_to_page(b); |
| 344 | __SetPageSlab(sp); |
| 345 | |
| 346 | spin_lock_irqsave(&slob_lock, flags); |
| 347 | sp->units = SLOB_UNITS(PAGE_SIZE); |
| 348 | sp->freelist = b; |
| 349 | INIT_LIST_HEAD(&sp->slab_list); |
| 350 | set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); |
| 351 | set_slob_page_free(sp, slob_list); |
| 352 | b = slob_page_alloc(sp, size, align, &_unused); |
| 353 | BUG_ON(!b); |
| 354 | spin_unlock_irqrestore(&slob_lock, flags); |
| 355 | } |
| 356 | if (unlikely(gfp & __GFP_ZERO)) |
| 357 | memset(b, 0, size); |
| 358 | return b; |
| 359 | } |
| 360 | |
| 361 | /* |
| 362 | * slob_free: entry point into the slob allocator. |
| 363 | */ |
| 364 | static void slob_free(void *block, int size) |
| 365 | { |
| 366 | struct page *sp; |
| 367 | slob_t *prev, *next, *b = (slob_t *)block; |
| 368 | slobidx_t units; |
| 369 | unsigned long flags; |
| 370 | struct list_head *slob_list; |
| 371 | |
| 372 | if (unlikely(ZERO_OR_NULL_PTR(block))) |
| 373 | return; |
| 374 | BUG_ON(!size); |
| 375 | |
| 376 | sp = virt_to_page(block); |
| 377 | units = SLOB_UNITS(size); |
| 378 | |
| 379 | spin_lock_irqsave(&slob_lock, flags); |
| 380 | |
| 381 | if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) { |
| 382 | /* Go directly to page allocator. Do not pass slob allocator */ |
| 383 | if (slob_page_free(sp)) |
| 384 | clear_slob_page_free(sp); |
| 385 | spin_unlock_irqrestore(&slob_lock, flags); |
| 386 | __ClearPageSlab(sp); |
| 387 | page_mapcount_reset(sp); |
| 388 | slob_free_pages(b, 0); |
| 389 | return; |
| 390 | } |
| 391 | |
| 392 | if (!slob_page_free(sp)) { |
| 393 | /* This slob page is about to become partially free. Easy! */ |
| 394 | sp->units = units; |
| 395 | sp->freelist = b; |
| 396 | set_slob(b, units, |
| 397 | (void *)((unsigned long)(b + |
| 398 | SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK)); |
| 399 | if (size < SLOB_BREAK1) |
| 400 | slob_list = &free_slob_small; |
| 401 | else if (size < SLOB_BREAK2) |
| 402 | slob_list = &free_slob_medium; |
| 403 | else |
| 404 | slob_list = &free_slob_large; |
| 405 | set_slob_page_free(sp, slob_list); |
| 406 | goto out; |
| 407 | } |
| 408 | |
| 409 | /* |
| 410 | * Otherwise the page is already partially free, so find reinsertion |
| 411 | * point. |
| 412 | */ |
| 413 | sp->units += units; |
| 414 | |
| 415 | if (b < (slob_t *)sp->freelist) { |
| 416 | if (b + units == sp->freelist) { |
| 417 | units += slob_units(sp->freelist); |
| 418 | sp->freelist = slob_next(sp->freelist); |
| 419 | } |
| 420 | set_slob(b, units, sp->freelist); |
| 421 | sp->freelist = b; |
| 422 | } else { |
| 423 | prev = sp->freelist; |
| 424 | next = slob_next(prev); |
| 425 | while (b > next) { |
| 426 | prev = next; |
| 427 | next = slob_next(prev); |
| 428 | } |
| 429 | |
| 430 | if (!slob_last(prev) && b + units == next) { |
| 431 | units += slob_units(next); |
| 432 | set_slob(b, units, slob_next(next)); |
| 433 | } else |
| 434 | set_slob(b, units, next); |
| 435 | |
| 436 | if (prev + slob_units(prev) == b) { |
| 437 | units = slob_units(b) + slob_units(prev); |
| 438 | set_slob(prev, units, slob_next(b)); |
| 439 | } else |
| 440 | set_slob(prev, slob_units(prev), b); |
| 441 | } |
| 442 | out: |
| 443 | spin_unlock_irqrestore(&slob_lock, flags); |
| 444 | } |
| 445 | |
| 446 | /* |
| 447 | * End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend. |
| 448 | */ |
| 449 | |
| 450 | static __always_inline void * |
| 451 | __do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) |
| 452 | { |
| 453 | unsigned int *m; |
| 454 | int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN); |
| 455 | void *ret; |
| 456 | |
| 457 | gfp &= gfp_allowed_mask; |
| 458 | |
| 459 | fs_reclaim_acquire(gfp); |
| 460 | fs_reclaim_release(gfp); |
| 461 | |
| 462 | if (size < PAGE_SIZE - align) { |
| 463 | if (!size) |
| 464 | return ZERO_SIZE_PTR; |
| 465 | |
| 466 | m = slob_alloc(size + align, gfp, align, node); |
| 467 | |
| 468 | if (!m) |
| 469 | return NULL; |
| 470 | *m = size; |
| 471 | ret = (void *)m + align; |
| 472 | |
| 473 | trace_kmalloc_node(caller, ret, |
| 474 | size, size + align, gfp, node); |
| 475 | } else { |
| 476 | unsigned int order = get_order(size); |
| 477 | |
| 478 | if (likely(order)) |
| 479 | gfp |= __GFP_COMP; |
| 480 | ret = slob_new_pages(gfp, order, node); |
| 481 | |
| 482 | trace_kmalloc_node(caller, ret, |
| 483 | size, PAGE_SIZE << order, gfp, node); |
| 484 | } |
| 485 | |
| 486 | kmemleak_alloc(ret, size, 1, gfp); |
| 487 | return ret; |
| 488 | } |
| 489 | |
| 490 | void *__kmalloc(size_t size, gfp_t gfp) |
| 491 | { |
| 492 | return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); |
| 493 | } |
| 494 | EXPORT_SYMBOL(__kmalloc); |
| 495 | |
| 496 | void *__kmalloc_track_caller(size_t size, gfp_t gfp, unsigned long caller) |
| 497 | { |
| 498 | return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, caller); |
| 499 | } |
| 500 | |
| 501 | #ifdef CONFIG_NUMA |
| 502 | void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, |
| 503 | int node, unsigned long caller) |
| 504 | { |
| 505 | return __do_kmalloc_node(size, gfp, node, caller); |
| 506 | } |
| 507 | #endif |
| 508 | |
| 509 | void kfree(const void *block) |
| 510 | { |
| 511 | struct page *sp; |
| 512 | |
| 513 | trace_kfree(_RET_IP_, block); |
| 514 | |
| 515 | if (unlikely(ZERO_OR_NULL_PTR(block))) |
| 516 | return; |
| 517 | kmemleak_free(block); |
| 518 | |
| 519 | sp = virt_to_page(block); |
| 520 | if (PageSlab(sp)) { |
| 521 | int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN); |
| 522 | unsigned int *m = (unsigned int *)(block - align); |
| 523 | slob_free(m, *m + align); |
| 524 | } else |
| 525 | __free_pages(sp, compound_order(sp)); |
| 526 | } |
| 527 | EXPORT_SYMBOL(kfree); |
| 528 | |
| 529 | /* can't use ksize for kmem_cache_alloc memory, only kmalloc */ |
| 530 | size_t ksize(const void *block) |
| 531 | { |
| 532 | struct page *sp; |
| 533 | int align; |
| 534 | unsigned int *m; |
| 535 | |
| 536 | BUG_ON(!block); |
| 537 | if (unlikely(block == ZERO_SIZE_PTR)) |
| 538 | return 0; |
| 539 | |
| 540 | sp = virt_to_page(block); |
| 541 | if (unlikely(!PageSlab(sp))) |
| 542 | return PAGE_SIZE << compound_order(sp); |
| 543 | |
| 544 | align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN); |
| 545 | m = (unsigned int *)(block - align); |
| 546 | return SLOB_UNITS(*m) * SLOB_UNIT; |
| 547 | } |
| 548 | EXPORT_SYMBOL(ksize); |
| 549 | |
| 550 | int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) |
| 551 | { |
| 552 | if (flags & SLAB_TYPESAFE_BY_RCU) { |
| 553 | /* leave room for rcu footer at the end of object */ |
| 554 | c->size += sizeof(struct slob_rcu); |
| 555 | } |
| 556 | c->flags = flags; |
| 557 | return 0; |
| 558 | } |
| 559 | |
| 560 | static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node) |
| 561 | { |
| 562 | void *b; |
| 563 | |
| 564 | flags &= gfp_allowed_mask; |
| 565 | |
| 566 | fs_reclaim_acquire(flags); |
| 567 | fs_reclaim_release(flags); |
| 568 | |
| 569 | if (c->size < PAGE_SIZE) { |
| 570 | b = slob_alloc(c->size, flags, c->align, node); |
| 571 | trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size, |
| 572 | SLOB_UNITS(c->size) * SLOB_UNIT, |
| 573 | flags, node); |
| 574 | } else { |
| 575 | b = slob_new_pages(flags, get_order(c->size), node); |
| 576 | trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size, |
| 577 | PAGE_SIZE << get_order(c->size), |
| 578 | flags, node); |
| 579 | } |
| 580 | |
| 581 | if (b && c->ctor) { |
| 582 | WARN_ON_ONCE(flags & __GFP_ZERO); |
| 583 | c->ctor(b); |
| 584 | } |
| 585 | |
| 586 | kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); |
| 587 | return b; |
| 588 | } |
| 589 | |
| 590 | void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
| 591 | { |
| 592 | return slob_alloc_node(cachep, flags, NUMA_NO_NODE); |
| 593 | } |
| 594 | EXPORT_SYMBOL(kmem_cache_alloc); |
| 595 | |
| 596 | #ifdef CONFIG_NUMA |
| 597 | void *__kmalloc_node(size_t size, gfp_t gfp, int node) |
| 598 | { |
| 599 | return __do_kmalloc_node(size, gfp, node, _RET_IP_); |
| 600 | } |
| 601 | EXPORT_SYMBOL(__kmalloc_node); |
| 602 | |
| 603 | void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) |
| 604 | { |
| 605 | return slob_alloc_node(cachep, gfp, node); |
| 606 | } |
| 607 | EXPORT_SYMBOL(kmem_cache_alloc_node); |
| 608 | #endif |
| 609 | |
| 610 | static void __kmem_cache_free(void *b, int size) |
| 611 | { |
| 612 | if (size < PAGE_SIZE) |
| 613 | slob_free(b, size); |
| 614 | else |
| 615 | slob_free_pages(b, get_order(size)); |
| 616 | } |
| 617 | |
| 618 | static void kmem_rcu_free(struct rcu_head *head) |
| 619 | { |
| 620 | struct slob_rcu *slob_rcu = (struct slob_rcu *)head; |
| 621 | void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu)); |
| 622 | |
| 623 | __kmem_cache_free(b, slob_rcu->size); |
| 624 | } |
| 625 | |
| 626 | void kmem_cache_free(struct kmem_cache *c, void *b) |
| 627 | { |
| 628 | kmemleak_free_recursive(b, c->flags); |
| 629 | if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { |
| 630 | struct slob_rcu *slob_rcu; |
| 631 | slob_rcu = b + (c->size - sizeof(struct slob_rcu)); |
| 632 | slob_rcu->size = c->size; |
| 633 | call_rcu(&slob_rcu->head, kmem_rcu_free); |
| 634 | } else { |
| 635 | __kmem_cache_free(b, c->size); |
| 636 | } |
| 637 | |
| 638 | trace_kmem_cache_free(_RET_IP_, b); |
| 639 | } |
| 640 | EXPORT_SYMBOL(kmem_cache_free); |
| 641 | |
| 642 | void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) |
| 643 | { |
| 644 | __kmem_cache_free_bulk(s, size, p); |
| 645 | } |
| 646 | EXPORT_SYMBOL(kmem_cache_free_bulk); |
| 647 | |
| 648 | int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, |
| 649 | void **p) |
| 650 | { |
| 651 | return __kmem_cache_alloc_bulk(s, flags, size, p); |
| 652 | } |
| 653 | EXPORT_SYMBOL(kmem_cache_alloc_bulk); |
| 654 | |
| 655 | int __kmem_cache_shutdown(struct kmem_cache *c) |
| 656 | { |
| 657 | /* No way to check for remaining objects */ |
| 658 | return 0; |
| 659 | } |
| 660 | |
| 661 | void __kmem_cache_release(struct kmem_cache *c) |
| 662 | { |
| 663 | } |
| 664 | |
| 665 | int __kmem_cache_shrink(struct kmem_cache *d) |
| 666 | { |
| 667 | return 0; |
| 668 | } |
| 669 | |
| 670 | struct kmem_cache kmem_cache_boot = { |
| 671 | .name = "kmem_cache", |
| 672 | .size = sizeof(struct kmem_cache), |
| 673 | .flags = SLAB_PANIC, |
| 674 | .align = ARCH_KMALLOC_MINALIGN, |
| 675 | }; |
| 676 | |
| 677 | void __init kmem_cache_init(void) |
| 678 | { |
| 679 | kmem_cache = &kmem_cache_boot; |
| 680 | slab_state = UP; |
| 681 | } |
| 682 | |
| 683 | void __init kmem_cache_init_late(void) |
| 684 | { |
| 685 | slab_state = FULL; |
| 686 | } |