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13#include <linux/mm.h>
14#include <linux/slab.h>
15#include <linux/highmem.h>
16#include <linux/kasan.h>
17#include <linux/kmemleak.h>
18#include <linux/export.h>
19#include <linux/mempool.h>
20#include <linux/blkdev.h>
21#include <linux/writeback.h>
22#include "slab.h"
23
24#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB_DEBUG_ON)
25static void poison_error(mempool_t *pool, void *element, size_t size,
26 size_t byte)
27{
28 const int nr = pool->curr_nr;
29 const int start = max_t(int, byte - (BITS_PER_LONG / 8), 0);
30 const int end = min_t(int, byte + (BITS_PER_LONG / 8), size);
31 int i;
32
33 pr_err("BUG: mempool element poison mismatch\n");
34 pr_err("Mempool %p size %zu\n", pool, size);
35 pr_err(" nr=%d @ %p: %s0x", nr, element, start > 0 ? "... " : "");
36 for (i = start; i < end; i++)
37 pr_cont("%x ", *(u8 *)(element + i));
38 pr_cont("%s\n", end < size ? "..." : "");
39 dump_stack();
40}
41
42static void __check_element(mempool_t *pool, void *element, size_t size)
43{
44 u8 *obj = element;
45 size_t i;
46
47 for (i = 0; i < size; i++) {
48 u8 exp = (i < size - 1) ? POISON_FREE : POISON_END;
49
50 if (obj[i] != exp) {
51 poison_error(pool, element, size, i);
52 return;
53 }
54 }
55 memset(obj, POISON_INUSE, size);
56}
57
58static void check_element(mempool_t *pool, void *element)
59{
60
61 if (pool->free == mempool_free_slab || pool->free == mempool_kfree)
62 __check_element(pool, element, ksize(element));
63
64
65 if (pool->free == mempool_free_pages) {
66 int order = (int)(long)pool->pool_data;
67 void *addr = kmap_atomic((struct page *)element);
68
69 __check_element(pool, addr, 1UL << (PAGE_SHIFT + order));
70 kunmap_atomic(addr);
71 }
72}
73
74static void __poison_element(void *element, size_t size)
75{
76 u8 *obj = element;
77
78 memset(obj, POISON_FREE, size - 1);
79 obj[size - 1] = POISON_END;
80}
81
82static void poison_element(mempool_t *pool, void *element)
83{
84
85 if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc)
86 __poison_element(element, ksize(element));
87
88
89 if (pool->alloc == mempool_alloc_pages) {
90 int order = (int)(long)pool->pool_data;
91 void *addr = kmap_atomic((struct page *)element);
92
93 __poison_element(addr, 1UL << (PAGE_SHIFT + order));
94 kunmap_atomic(addr);
95 }
96}
97#else
98static inline void check_element(mempool_t *pool, void *element)
99{
100}
101static inline void poison_element(mempool_t *pool, void *element)
102{
103}
104#endif
105
106static __always_inline void kasan_poison_element(mempool_t *pool, void *element)
107{
108 if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc)
109 kasan_poison_kfree(element, _RET_IP_);
110 if (pool->alloc == mempool_alloc_pages)
111 kasan_free_pages(element, (unsigned long)pool->pool_data);
112}
113
114static void kasan_unpoison_element(mempool_t *pool, void *element)
115{
116 if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc)
117 kasan_unpoison_slab(element);
118 if (pool->alloc == mempool_alloc_pages)
119 kasan_alloc_pages(element, (unsigned long)pool->pool_data);
120}
121
122static __always_inline void add_element(mempool_t *pool, void *element)
123{
124 BUG_ON(pool->curr_nr >= pool->min_nr);
125 poison_element(pool, element);
126 kasan_poison_element(pool, element);
127 pool->elements[pool->curr_nr++] = element;
128}
129
130static void *remove_element(mempool_t *pool)
131{
132 void *element = pool->elements[--pool->curr_nr];
133
134 BUG_ON(pool->curr_nr < 0);
135 kasan_unpoison_element(pool, element);
136 check_element(pool, element);
137 return element;
138}
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150
151void mempool_exit(mempool_t *pool)
152{
153 while (pool->curr_nr) {
154 void *element = remove_element(pool);
155 pool->free(element, pool->pool_data);
156 }
157 kfree(pool->elements);
158 pool->elements = NULL;
159}
160EXPORT_SYMBOL(mempool_exit);
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170void mempool_destroy(mempool_t *pool)
171{
172 if (unlikely(!pool))
173 return;
174
175 mempool_exit(pool);
176 kfree(pool);
177}
178EXPORT_SYMBOL(mempool_destroy);
179
180int mempool_init_node(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn,
181 mempool_free_t *free_fn, void *pool_data,
182 gfp_t gfp_mask, int node_id)
183{
184 spin_lock_init(&pool->lock);
185 pool->min_nr = min_nr;
186 pool->pool_data = pool_data;
187 pool->alloc = alloc_fn;
188 pool->free = free_fn;
189 init_waitqueue_head(&pool->wait);
190
191 pool->elements = kmalloc_array_node(min_nr, sizeof(void *),
192 gfp_mask, node_id);
193 if (!pool->elements)
194 return -ENOMEM;
195
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199 while (pool->curr_nr < pool->min_nr) {
200 void *element;
201
202 element = pool->alloc(gfp_mask, pool->pool_data);
203 if (unlikely(!element)) {
204 mempool_exit(pool);
205 return -ENOMEM;
206 }
207 add_element(pool, element);
208 }
209
210 return 0;
211}
212EXPORT_SYMBOL(mempool_init_node);
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225
226int mempool_init(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn,
227 mempool_free_t *free_fn, void *pool_data)
228{
229 return mempool_init_node(pool, min_nr, alloc_fn, free_fn,
230 pool_data, GFP_KERNEL, NUMA_NO_NODE);
231
232}
233EXPORT_SYMBOL(mempool_init);
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249mempool_t *mempool_create(int min_nr, mempool_alloc_t *alloc_fn,
250 mempool_free_t *free_fn, void *pool_data)
251{
252 return mempool_create_node(min_nr,alloc_fn,free_fn, pool_data,
253 GFP_KERNEL, NUMA_NO_NODE);
254}
255EXPORT_SYMBOL(mempool_create);
256
257mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn,
258 mempool_free_t *free_fn, void *pool_data,
259 gfp_t gfp_mask, int node_id)
260{
261 mempool_t *pool;
262
263 pool = kzalloc_node(sizeof(*pool), gfp_mask, node_id);
264 if (!pool)
265 return NULL;
266
267 if (mempool_init_node(pool, min_nr, alloc_fn, free_fn, pool_data,
268 gfp_mask, node_id)) {
269 kfree(pool);
270 return NULL;
271 }
272
273 return pool;
274}
275EXPORT_SYMBOL(mempool_create_node);
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293int mempool_resize(mempool_t *pool, int new_min_nr)
294{
295 void *element;
296 void **new_elements;
297 unsigned long flags;
298
299 BUG_ON(new_min_nr <= 0);
300 might_sleep();
301
302 spin_lock_irqsave(&pool->lock, flags);
303 if (new_min_nr <= pool->min_nr) {
304 while (new_min_nr < pool->curr_nr) {
305 element = remove_element(pool);
306 spin_unlock_irqrestore(&pool->lock, flags);
307 pool->free(element, pool->pool_data);
308 spin_lock_irqsave(&pool->lock, flags);
309 }
310 pool->min_nr = new_min_nr;
311 goto out_unlock;
312 }
313 spin_unlock_irqrestore(&pool->lock, flags);
314
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316 new_elements = kmalloc_array(new_min_nr, sizeof(*new_elements),
317 GFP_KERNEL);
318 if (!new_elements)
319 return -ENOMEM;
320
321 spin_lock_irqsave(&pool->lock, flags);
322 if (unlikely(new_min_nr <= pool->min_nr)) {
323
324 spin_unlock_irqrestore(&pool->lock, flags);
325 kfree(new_elements);
326 goto out;
327 }
328 memcpy(new_elements, pool->elements,
329 pool->curr_nr * sizeof(*new_elements));
330 kfree(pool->elements);
331 pool->elements = new_elements;
332 pool->min_nr = new_min_nr;
333
334 while (pool->curr_nr < pool->min_nr) {
335 spin_unlock_irqrestore(&pool->lock, flags);
336 element = pool->alloc(GFP_KERNEL, pool->pool_data);
337 if (!element)
338 goto out;
339 spin_lock_irqsave(&pool->lock, flags);
340 if (pool->curr_nr < pool->min_nr) {
341 add_element(pool, element);
342 } else {
343 spin_unlock_irqrestore(&pool->lock, flags);
344 pool->free(element, pool->pool_data);
345 goto out;
346 }
347 }
348out_unlock:
349 spin_unlock_irqrestore(&pool->lock, flags);
350out:
351 return 0;
352}
353EXPORT_SYMBOL(mempool_resize);
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367void *mempool_alloc(mempool_t *pool, gfp_t gfp_mask)
368{
369 void *element;
370 unsigned long flags;
371 wait_queue_entry_t wait;
372 gfp_t gfp_temp;
373
374 VM_WARN_ON_ONCE(gfp_mask & __GFP_ZERO);
375 might_sleep_if(gfp_mask & __GFP_DIRECT_RECLAIM);
376
377 gfp_mask |= __GFP_NOMEMALLOC;
378 gfp_mask |= __GFP_NORETRY;
379 gfp_mask |= __GFP_NOWARN;
380
381 gfp_temp = gfp_mask & ~(__GFP_DIRECT_RECLAIM|__GFP_IO);
382
383repeat_alloc:
384
385 element = pool->alloc(gfp_temp, pool->pool_data);
386 if (likely(element != NULL))
387 return element;
388
389 spin_lock_irqsave(&pool->lock, flags);
390 if (likely(pool->curr_nr)) {
391 element = remove_element(pool);
392 spin_unlock_irqrestore(&pool->lock, flags);
393
394 smp_wmb();
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399 kmemleak_update_trace(element);
400 return element;
401 }
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407 if (gfp_temp != gfp_mask) {
408 spin_unlock_irqrestore(&pool->lock, flags);
409 gfp_temp = gfp_mask;
410 goto repeat_alloc;
411 }
412
413
414 if (!(gfp_mask & __GFP_DIRECT_RECLAIM)) {
415 spin_unlock_irqrestore(&pool->lock, flags);
416 return NULL;
417 }
418
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420 init_wait(&wait);
421 prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE);
422
423 spin_unlock_irqrestore(&pool->lock, flags);
424
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429 io_schedule_timeout(5*HZ);
430
431 finish_wait(&pool->wait, &wait);
432 goto repeat_alloc;
433}
434EXPORT_SYMBOL(mempool_alloc);
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444void mempool_free(void *element, mempool_t *pool)
445{
446 unsigned long flags;
447
448 if (unlikely(element == NULL))
449 return;
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465 smp_rmb();
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484 if (unlikely(pool->curr_nr < pool->min_nr)) {
485 spin_lock_irqsave(&pool->lock, flags);
486 if (likely(pool->curr_nr < pool->min_nr)) {
487 add_element(pool, element);
488 spin_unlock_irqrestore(&pool->lock, flags);
489 wake_up(&pool->wait);
490 return;
491 }
492 spin_unlock_irqrestore(&pool->lock, flags);
493 }
494 pool->free(element, pool->pool_data);
495}
496EXPORT_SYMBOL(mempool_free);
497
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500
501void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data)
502{
503 struct kmem_cache *mem = pool_data;
504 VM_BUG_ON(mem->ctor);
505 return kmem_cache_alloc(mem, gfp_mask);
506}
507EXPORT_SYMBOL(mempool_alloc_slab);
508
509void mempool_free_slab(void *element, void *pool_data)
510{
511 struct kmem_cache *mem = pool_data;
512 kmem_cache_free(mem, element);
513}
514EXPORT_SYMBOL(mempool_free_slab);
515
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520void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data)
521{
522 size_t size = (size_t)pool_data;
523 return kmalloc(size, gfp_mask);
524}
525EXPORT_SYMBOL(mempool_kmalloc);
526
527void mempool_kfree(void *element, void *pool_data)
528{
529 kfree(element);
530}
531EXPORT_SYMBOL(mempool_kfree);
532
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537void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data)
538{
539 int order = (int)(long)pool_data;
540 return alloc_pages(gfp_mask, order);
541}
542EXPORT_SYMBOL(mempool_alloc_pages);
543
544void mempool_free_pages(void *element, void *pool_data)
545{
546 int order = (int)(long)pool_data;
547 __free_pages(element, order);
548}
549EXPORT_SYMBOL(mempool_free_pages);
550