Branch data Line data Source code
1 : : // SPDX-License-Identifier: GPL-2.0-only
2 : : /*
3 : : * Basic general purpose allocator for managing special purpose
4 : : * memory, for example, memory that is not managed by the regular
5 : : * kmalloc/kfree interface. Uses for this includes on-device special
6 : : * memory, uncached memory etc.
7 : : *
8 : : * It is safe to use the allocator in NMI handlers and other special
9 : : * unblockable contexts that could otherwise deadlock on locks. This
10 : : * is implemented by using atomic operations and retries on any
11 : : * conflicts. The disadvantage is that there may be livelocks in
12 : : * extreme cases. For better scalability, one allocator can be used
13 : : * for each CPU.
14 : : *
15 : : * The lockless operation only works if there is enough memory
16 : : * available. If new memory is added to the pool a lock has to be
17 : : * still taken. So any user relying on locklessness has to ensure
18 : : * that sufficient memory is preallocated.
19 : : *
20 : : * The basic atomic operation of this allocator is cmpxchg on long.
21 : : * On architectures that don't have NMI-safe cmpxchg implementation,
22 : : * the allocator can NOT be used in NMI handler. So code uses the
23 : : * allocator in NMI handler should depend on
24 : : * CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG.
25 : : *
26 : : * Copyright 2005 (C) Jes Sorensen <jes@trained-monkey.org>
27 : : */
28 : :
29 : : #include <linux/slab.h>
30 : : #include <linux/export.h>
31 : : #include <linux/bitmap.h>
32 : : #include <linux/rculist.h>
33 : : #include <linux/interrupt.h>
34 : : #include <linux/genalloc.h>
35 : : #include <linux/of_device.h>
36 : : #include <linux/vmalloc.h>
37 : :
38 : : static inline size_t chunk_size(const struct gen_pool_chunk *chunk)
39 : : {
40 : 50942 : return chunk->end_addr - chunk->start_addr + 1;
41 : : }
42 : :
43 : 50942 : static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
44 : : {
45 : : unsigned long val, nval;
46 : :
47 : 50942 : nval = *addr;
48 : : do {
49 : : val = nval;
50 [ + - ]: 50942 : if (val & mask_to_set)
51 : : return -EBUSY;
52 : 50942 : cpu_relax();
53 [ - + ]: 50942 : } while ((nval = cmpxchg(addr, val, val | mask_to_set)) != val);
54 : :
55 : : return 0;
56 : : }
57 : :
58 : 48920 : static int clear_bits_ll(unsigned long *addr, unsigned long mask_to_clear)
59 : : {
60 : : unsigned long val, nval;
61 : :
62 : 48920 : nval = *addr;
63 : : do {
64 : : val = nval;
65 [ + - ]: 48920 : if ((val & mask_to_clear) != mask_to_clear)
66 : : return -EBUSY;
67 : 48920 : cpu_relax();
68 [ - + ]: 48920 : } while ((nval = cmpxchg(addr, val, val & ~mask_to_clear)) != val);
69 : :
70 : : return 0;
71 : : }
72 : :
73 : : /*
74 : : * bitmap_set_ll - set the specified number of bits at the specified position
75 : : * @map: pointer to a bitmap
76 : : * @start: a bit position in @map
77 : : * @nr: number of bits to set
78 : : *
79 : : * Set @nr bits start from @start in @map lock-lessly. Several users
80 : : * can set/clear the same bitmap simultaneously without lock. If two
81 : : * users set the same bit, one user will return remain bits, otherwise
82 : : * return 0.
83 : : */
84 : 50942 : static int bitmap_set_ll(unsigned long *map, int start, int nr)
85 : : {
86 : 50942 : unsigned long *p = map + BIT_WORD(start);
87 : 50942 : const int size = start + nr;
88 : 50942 : int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
89 : 50942 : unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
90 : :
91 [ + + ]: 102288 : while (nr - bits_to_set >= 0) {
92 [ - + ]: 404 : if (set_bits_ll(p, mask_to_set))
93 : 0 : return nr;
94 : : nr -= bits_to_set;
95 : : bits_to_set = BITS_PER_LONG;
96 : : mask_to_set = ~0UL;
97 : 404 : p++;
98 : : }
99 [ + + ]: 50942 : if (nr) {
100 : 50538 : mask_to_set &= BITMAP_LAST_WORD_MASK(size);
101 [ - + ]: 50538 : if (set_bits_ll(p, mask_to_set))
102 : 0 : return nr;
103 : : }
104 : :
105 : : return 0;
106 : : }
107 : :
108 : : /*
109 : : * bitmap_clear_ll - clear the specified number of bits at the specified position
110 : : * @map: pointer to a bitmap
111 : : * @start: a bit position in @map
112 : : * @nr: number of bits to set
113 : : *
114 : : * Clear @nr bits start from @start in @map lock-lessly. Several users
115 : : * can set/clear the same bitmap simultaneously without lock. If two
116 : : * users clear the same bit, one user will return remain bits,
117 : : * otherwise return 0.
118 : : */
119 : 48920 : static int bitmap_clear_ll(unsigned long *map, int start, int nr)
120 : : {
121 : 48920 : unsigned long *p = map + BIT_WORD(start);
122 : 48920 : const int size = start + nr;
123 : 48920 : int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
124 : 48920 : unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
125 : :
126 [ - + ]: 97840 : while (nr - bits_to_clear >= 0) {
127 [ # # ]: 0 : if (clear_bits_ll(p, mask_to_clear))
128 : 0 : return nr;
129 : : nr -= bits_to_clear;
130 : : bits_to_clear = BITS_PER_LONG;
131 : : mask_to_clear = ~0UL;
132 : 0 : p++;
133 : : }
134 [ + - ]: 48920 : if (nr) {
135 : 48920 : mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
136 [ - + ]: 48920 : if (clear_bits_ll(p, mask_to_clear))
137 : 0 : return nr;
138 : : }
139 : :
140 : : return 0;
141 : : }
142 : :
143 : : /**
144 : : * gen_pool_create - create a new special memory pool
145 : : * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
146 : : * @nid: node id of the node the pool structure should be allocated on, or -1
147 : : *
148 : : * Create a new special memory pool that can be used to manage special purpose
149 : : * memory not managed by the regular kmalloc/kfree interface.
150 : : */
151 : 404 : struct gen_pool *gen_pool_create(int min_alloc_order, int nid)
152 : : {
153 : : struct gen_pool *pool;
154 : :
155 : : pool = kmalloc_node(sizeof(struct gen_pool), GFP_KERNEL, nid);
156 [ + - ]: 404 : if (pool != NULL) {
157 : 404 : spin_lock_init(&pool->lock);
158 : 404 : INIT_LIST_HEAD(&pool->chunks);
159 : 404 : pool->min_alloc_order = min_alloc_order;
160 : 404 : pool->algo = gen_pool_first_fit;
161 : 404 : pool->data = NULL;
162 : 404 : pool->name = NULL;
163 : : }
164 : 404 : return pool;
165 : : }
166 : : EXPORT_SYMBOL(gen_pool_create);
167 : :
168 : : /**
169 : : * gen_pool_add_owner- add a new chunk of special memory to the pool
170 : : * @pool: pool to add new memory chunk to
171 : : * @virt: virtual starting address of memory chunk to add to pool
172 : : * @phys: physical starting address of memory chunk to add to pool
173 : : * @size: size in bytes of the memory chunk to add to pool
174 : : * @nid: node id of the node the chunk structure and bitmap should be
175 : : * allocated on, or -1
176 : : * @owner: private data the publisher would like to recall at alloc time
177 : : *
178 : : * Add a new chunk of special memory to the specified pool.
179 : : *
180 : : * Returns 0 on success or a -ve errno on failure.
181 : : */
182 : 404 : int gen_pool_add_owner(struct gen_pool *pool, unsigned long virt, phys_addr_t phys,
183 : : size_t size, int nid, void *owner)
184 : : {
185 : : struct gen_pool_chunk *chunk;
186 : 404 : int nbits = size >> pool->min_alloc_order;
187 : 404 : int nbytes = sizeof(struct gen_pool_chunk) +
188 : 404 : BITS_TO_LONGS(nbits) * sizeof(long);
189 : :
190 : 404 : chunk = vzalloc_node(nbytes, nid);
191 [ + - ]: 404 : if (unlikely(chunk == NULL))
192 : : return -ENOMEM;
193 : :
194 : 404 : chunk->phys_addr = phys;
195 : 404 : chunk->start_addr = virt;
196 : 404 : chunk->end_addr = virt + size - 1;
197 : 404 : chunk->owner = owner;
198 : : atomic_long_set(&chunk->avail, size);
199 : :
200 : : spin_lock(&pool->lock);
201 : 404 : list_add_rcu(&chunk->next_chunk, &pool->chunks);
202 : : spin_unlock(&pool->lock);
203 : :
204 : 404 : return 0;
205 : : }
206 : : EXPORT_SYMBOL(gen_pool_add_owner);
207 : :
208 : : /**
209 : : * gen_pool_virt_to_phys - return the physical address of memory
210 : : * @pool: pool to allocate from
211 : : * @addr: starting address of memory
212 : : *
213 : : * Returns the physical address on success, or -1 on error.
214 : : */
215 : 50942 : phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long addr)
216 : : {
217 : : struct gen_pool_chunk *chunk;
218 : : phys_addr_t paddr = -1;
219 : :
220 : : rcu_read_lock();
221 [ + - ]: 50942 : list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
222 [ + - + - ]: 50942 : if (addr >= chunk->start_addr && addr <= chunk->end_addr) {
223 : 50942 : paddr = chunk->phys_addr + (addr - chunk->start_addr);
224 : 50942 : break;
225 : : }
226 : : }
227 : : rcu_read_unlock();
228 : :
229 : 50942 : return paddr;
230 : : }
231 : : EXPORT_SYMBOL(gen_pool_virt_to_phys);
232 : :
233 : : /**
234 : : * gen_pool_destroy - destroy a special memory pool
235 : : * @pool: pool to destroy
236 : : *
237 : : * Destroy the specified special memory pool. Verifies that there are no
238 : : * outstanding allocations.
239 : : */
240 : 0 : void gen_pool_destroy(struct gen_pool *pool)
241 : : {
242 : : struct list_head *_chunk, *_next_chunk;
243 : : struct gen_pool_chunk *chunk;
244 : 0 : int order = pool->min_alloc_order;
245 : : int bit, end_bit;
246 : :
247 [ # # ]: 0 : list_for_each_safe(_chunk, _next_chunk, &pool->chunks) {
248 : : chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
249 : : list_del(&chunk->next_chunk);
250 : :
251 : 0 : end_bit = chunk_size(chunk) >> order;
252 : 0 : bit = find_next_bit(chunk->bits, end_bit, 0);
253 [ # # ]: 0 : BUG_ON(bit < end_bit);
254 : :
255 : 0 : vfree(chunk);
256 : : }
257 : 0 : kfree_const(pool->name);
258 : 0 : kfree(pool);
259 : 0 : }
260 : : EXPORT_SYMBOL(gen_pool_destroy);
261 : :
262 : : /**
263 : : * gen_pool_alloc_algo_owner - allocate special memory from the pool
264 : : * @pool: pool to allocate from
265 : : * @size: number of bytes to allocate from the pool
266 : : * @algo: algorithm passed from caller
267 : : * @data: data passed to algorithm
268 : : * @owner: optionally retrieve the chunk owner
269 : : *
270 : : * Allocate the requested number of bytes from the specified pool.
271 : : * Uses the pool allocation function (with first-fit algorithm by default).
272 : : * Can not be used in NMI handler on architectures without
273 : : * NMI-safe cmpxchg implementation.
274 : : */
275 : 50942 : unsigned long gen_pool_alloc_algo_owner(struct gen_pool *pool, size_t size,
276 : : genpool_algo_t algo, void *data, void **owner)
277 : : {
278 : : struct gen_pool_chunk *chunk;
279 : : unsigned long addr = 0;
280 : 50942 : int order = pool->min_alloc_order;
281 : : int nbits, start_bit, end_bit, remain;
282 : :
283 : : #ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
284 [ - + ]: 50942 : BUG_ON(in_nmi());
285 : : #endif
286 : :
287 [ - + ]: 50942 : if (owner)
288 : 0 : *owner = NULL;
289 : :
290 [ + - ]: 50942 : if (size == 0)
291 : : return 0;
292 : :
293 : 50942 : nbits = (size + (1UL << order) - 1) >> order;
294 : : rcu_read_lock();
295 [ + - ]: 50942 : list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
296 [ - + ]: 50942 : if (size > atomic_long_read(&chunk->avail))
297 : 0 : continue;
298 : :
299 : : start_bit = 0;
300 : 50942 : end_bit = chunk_size(chunk) >> order;
301 : : retry:
302 : 50942 : start_bit = algo(chunk->bits, end_bit, start_bit,
303 : : nbits, data, pool, chunk->start_addr);
304 [ - + ]: 50942 : if (start_bit >= end_bit)
305 : 0 : continue;
306 : 50942 : remain = bitmap_set_ll(chunk->bits, start_bit, nbits);
307 [ - + ]: 50942 : if (remain) {
308 : 0 : remain = bitmap_clear_ll(chunk->bits, start_bit,
309 : : nbits - remain);
310 [ # # ]: 0 : BUG_ON(remain);
311 : : goto retry;
312 : : }
313 : :
314 : 50942 : addr = chunk->start_addr + ((unsigned long)start_bit << order);
315 : 50942 : size = nbits << order;
316 : 50942 : atomic_long_sub(size, &chunk->avail);
317 [ - + ]: 50942 : if (owner)
318 : 0 : *owner = chunk->owner;
319 : : break;
320 : : }
321 : : rcu_read_unlock();
322 : 50942 : return addr;
323 : : }
324 : : EXPORT_SYMBOL(gen_pool_alloc_algo_owner);
325 : :
326 : : /**
327 : : * gen_pool_dma_alloc - allocate special memory from the pool for DMA usage
328 : : * @pool: pool to allocate from
329 : : * @size: number of bytes to allocate from the pool
330 : : * @dma: dma-view physical address return value. Use %NULL if unneeded.
331 : : *
332 : : * Allocate the requested number of bytes from the specified pool.
333 : : * Uses the pool allocation function (with first-fit algorithm by default).
334 : : * Can not be used in NMI handler on architectures without
335 : : * NMI-safe cmpxchg implementation.
336 : : *
337 : : * Return: virtual address of the allocated memory, or %NULL on failure
338 : : */
339 : 0 : void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
340 : : {
341 : 0 : return gen_pool_dma_alloc_algo(pool, size, dma, pool->algo, pool->data);
342 : : }
343 : : EXPORT_SYMBOL(gen_pool_dma_alloc);
344 : :
345 : : /**
346 : : * gen_pool_dma_alloc_algo - allocate special memory from the pool for DMA
347 : : * usage with the given pool algorithm
348 : : * @pool: pool to allocate from
349 : : * @size: number of bytes to allocate from the pool
350 : : * @dma: DMA-view physical address return value. Use %NULL if unneeded.
351 : : * @algo: algorithm passed from caller
352 : : * @data: data passed to algorithm
353 : : *
354 : : * Allocate the requested number of bytes from the specified pool. Uses the
355 : : * given pool allocation function. Can not be used in NMI handler on
356 : : * architectures without NMI-safe cmpxchg implementation.
357 : : *
358 : : * Return: virtual address of the allocated memory, or %NULL on failure
359 : : */
360 : 0 : void *gen_pool_dma_alloc_algo(struct gen_pool *pool, size_t size,
361 : : dma_addr_t *dma, genpool_algo_t algo, void *data)
362 : : {
363 : : unsigned long vaddr;
364 : :
365 [ # # ]: 0 : if (!pool)
366 : : return NULL;
367 : :
368 : : vaddr = gen_pool_alloc_algo(pool, size, algo, data);
369 [ # # ]: 0 : if (!vaddr)
370 : : return NULL;
371 : :
372 [ # # ]: 0 : if (dma)
373 : 0 : *dma = gen_pool_virt_to_phys(pool, vaddr);
374 : :
375 : 0 : return (void *)vaddr;
376 : : }
377 : : EXPORT_SYMBOL(gen_pool_dma_alloc_algo);
378 : :
379 : : /**
380 : : * gen_pool_dma_alloc_align - allocate special memory from the pool for DMA
381 : : * usage with the given alignment
382 : : * @pool: pool to allocate from
383 : : * @size: number of bytes to allocate from the pool
384 : : * @dma: DMA-view physical address return value. Use %NULL if unneeded.
385 : : * @align: alignment in bytes for starting address
386 : : *
387 : : * Allocate the requested number bytes from the specified pool, with the given
388 : : * alignment restriction. Can not be used in NMI handler on architectures
389 : : * without NMI-safe cmpxchg implementation.
390 : : *
391 : : * Return: virtual address of the allocated memory, or %NULL on failure
392 : : */
393 : 0 : void *gen_pool_dma_alloc_align(struct gen_pool *pool, size_t size,
394 : : dma_addr_t *dma, int align)
395 : : {
396 : 0 : struct genpool_data_align data = { .align = align };
397 : :
398 : 0 : return gen_pool_dma_alloc_algo(pool, size, dma,
399 : : gen_pool_first_fit_align, &data);
400 : : }
401 : : EXPORT_SYMBOL(gen_pool_dma_alloc_align);
402 : :
403 : : /**
404 : : * gen_pool_dma_zalloc - allocate special zeroed memory from the pool for
405 : : * DMA usage
406 : : * @pool: pool to allocate from
407 : : * @size: number of bytes to allocate from the pool
408 : : * @dma: dma-view physical address return value. Use %NULL if unneeded.
409 : : *
410 : : * Allocate the requested number of zeroed bytes from the specified pool.
411 : : * Uses the pool allocation function (with first-fit algorithm by default).
412 : : * Can not be used in NMI handler on architectures without
413 : : * NMI-safe cmpxchg implementation.
414 : : *
415 : : * Return: virtual address of the allocated zeroed memory, or %NULL on failure
416 : : */
417 : 0 : void *gen_pool_dma_zalloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
418 : : {
419 : 0 : return gen_pool_dma_zalloc_algo(pool, size, dma, pool->algo, pool->data);
420 : : }
421 : : EXPORT_SYMBOL(gen_pool_dma_zalloc);
422 : :
423 : : /**
424 : : * gen_pool_dma_zalloc_algo - allocate special zeroed memory from the pool for
425 : : * DMA usage with the given pool algorithm
426 : : * @pool: pool to allocate from
427 : : * @size: number of bytes to allocate from the pool
428 : : * @dma: DMA-view physical address return value. Use %NULL if unneeded.
429 : : * @algo: algorithm passed from caller
430 : : * @data: data passed to algorithm
431 : : *
432 : : * Allocate the requested number of zeroed bytes from the specified pool. Uses
433 : : * the given pool allocation function. Can not be used in NMI handler on
434 : : * architectures without NMI-safe cmpxchg implementation.
435 : : *
436 : : * Return: virtual address of the allocated zeroed memory, or %NULL on failure
437 : : */
438 : 0 : void *gen_pool_dma_zalloc_algo(struct gen_pool *pool, size_t size,
439 : : dma_addr_t *dma, genpool_algo_t algo, void *data)
440 : : {
441 : 0 : void *vaddr = gen_pool_dma_alloc_algo(pool, size, dma, algo, data);
442 : :
443 [ # # ]: 0 : if (vaddr)
444 : 0 : memset(vaddr, 0, size);
445 : :
446 : 0 : return vaddr;
447 : : }
448 : : EXPORT_SYMBOL(gen_pool_dma_zalloc_algo);
449 : :
450 : : /**
451 : : * gen_pool_dma_zalloc_align - allocate special zeroed memory from the pool for
452 : : * DMA usage with the given alignment
453 : : * @pool: pool to allocate from
454 : : * @size: number of bytes to allocate from the pool
455 : : * @dma: DMA-view physical address return value. Use %NULL if unneeded.
456 : : * @align: alignment in bytes for starting address
457 : : *
458 : : * Allocate the requested number of zeroed bytes from the specified pool,
459 : : * with the given alignment restriction. Can not be used in NMI handler on
460 : : * architectures without NMI-safe cmpxchg implementation.
461 : : *
462 : : * Return: virtual address of the allocated zeroed memory, or %NULL on failure
463 : : */
464 : 0 : void *gen_pool_dma_zalloc_align(struct gen_pool *pool, size_t size,
465 : : dma_addr_t *dma, int align)
466 : : {
467 : 0 : struct genpool_data_align data = { .align = align };
468 : :
469 : 0 : return gen_pool_dma_zalloc_algo(pool, size, dma,
470 : : gen_pool_first_fit_align, &data);
471 : : }
472 : : EXPORT_SYMBOL(gen_pool_dma_zalloc_align);
473 : :
474 : : /**
475 : : * gen_pool_free - free allocated special memory back to the pool
476 : : * @pool: pool to free to
477 : : * @addr: starting address of memory to free back to pool
478 : : * @size: size in bytes of memory to free
479 : : * @owner: private data stashed at gen_pool_add() time
480 : : *
481 : : * Free previously allocated special memory back to the specified
482 : : * pool. Can not be used in NMI handler on architectures without
483 : : * NMI-safe cmpxchg implementation.
484 : : */
485 : 48920 : void gen_pool_free_owner(struct gen_pool *pool, unsigned long addr, size_t size,
486 : : void **owner)
487 : : {
488 : : struct gen_pool_chunk *chunk;
489 : 48920 : int order = pool->min_alloc_order;
490 : : int start_bit, nbits, remain;
491 : :
492 : : #ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
493 [ - + ]: 48920 : BUG_ON(in_nmi());
494 : : #endif
495 : :
496 [ - + ]: 48920 : if (owner)
497 : 0 : *owner = NULL;
498 : :
499 : 48920 : nbits = (size + (1UL << order) - 1) >> order;
500 : : rcu_read_lock();
501 [ + - ]: 48920 : list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
502 [ + - + - ]: 48920 : if (addr >= chunk->start_addr && addr <= chunk->end_addr) {
503 [ - + ]: 48920 : BUG_ON(addr + size - 1 > chunk->end_addr);
504 : 48920 : start_bit = (addr - chunk->start_addr) >> order;
505 : 48920 : remain = bitmap_clear_ll(chunk->bits, start_bit, nbits);
506 [ - + ]: 48920 : BUG_ON(remain);
507 : 48920 : size = nbits << order;
508 : 48920 : atomic_long_add(size, &chunk->avail);
509 [ - + ]: 48920 : if (owner)
510 : 0 : *owner = chunk->owner;
511 : : rcu_read_unlock();
512 : 48920 : return;
513 : : }
514 : : }
515 : : rcu_read_unlock();
516 : 0 : BUG();
517 : : }
518 : : EXPORT_SYMBOL(gen_pool_free_owner);
519 : :
520 : : /**
521 : : * gen_pool_for_each_chunk - call func for every chunk of generic memory pool
522 : : * @pool: the generic memory pool
523 : : * @func: func to call
524 : : * @data: additional data used by @func
525 : : *
526 : : * Call @func for every chunk of generic memory pool. The @func is
527 : : * called with rcu_read_lock held.
528 : : */
529 : 0 : void gen_pool_for_each_chunk(struct gen_pool *pool,
530 : : void (*func)(struct gen_pool *pool, struct gen_pool_chunk *chunk, void *data),
531 : : void *data)
532 : : {
533 : : struct gen_pool_chunk *chunk;
534 : :
535 : : rcu_read_lock();
536 [ # # ]: 0 : list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk)
537 : 0 : func(pool, chunk, data);
538 : : rcu_read_unlock();
539 : 0 : }
540 : : EXPORT_SYMBOL(gen_pool_for_each_chunk);
541 : :
542 : : /**
543 : : * addr_in_gen_pool - checks if an address falls within the range of a pool
544 : : * @pool: the generic memory pool
545 : : * @start: start address
546 : : * @size: size of the region
547 : : *
548 : : * Check if the range of addresses falls within the specified pool. Returns
549 : : * true if the entire range is contained in the pool and false otherwise.
550 : : */
551 : 48920 : bool addr_in_gen_pool(struct gen_pool *pool, unsigned long start,
552 : : size_t size)
553 : : {
554 : : bool found = false;
555 : 48920 : unsigned long end = start + size - 1;
556 : : struct gen_pool_chunk *chunk;
557 : :
558 : : rcu_read_lock();
559 [ + - ]: 48920 : list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk) {
560 [ + - + - ]: 48920 : if (start >= chunk->start_addr && start <= chunk->end_addr) {
561 [ - + ]: 48920 : if (end <= chunk->end_addr) {
562 : : found = true;
563 : : break;
564 : : }
565 : : }
566 : : }
567 : : rcu_read_unlock();
568 : 48920 : return found;
569 : : }
570 : :
571 : : /**
572 : : * gen_pool_avail - get available free space of the pool
573 : : * @pool: pool to get available free space
574 : : *
575 : : * Return available free space of the specified pool.
576 : : */
577 : 0 : size_t gen_pool_avail(struct gen_pool *pool)
578 : : {
579 : : struct gen_pool_chunk *chunk;
580 : : size_t avail = 0;
581 : :
582 : : rcu_read_lock();
583 [ # # ]: 0 : list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk)
584 : 0 : avail += atomic_long_read(&chunk->avail);
585 : : rcu_read_unlock();
586 : 0 : return avail;
587 : : }
588 : : EXPORT_SYMBOL_GPL(gen_pool_avail);
589 : :
590 : : /**
591 : : * gen_pool_size - get size in bytes of memory managed by the pool
592 : : * @pool: pool to get size
593 : : *
594 : : * Return size in bytes of memory managed by the pool.
595 : : */
596 : 0 : size_t gen_pool_size(struct gen_pool *pool)
597 : : {
598 : : struct gen_pool_chunk *chunk;
599 : : size_t size = 0;
600 : :
601 : : rcu_read_lock();
602 [ # # ]: 0 : list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk)
603 : 0 : size += chunk_size(chunk);
604 : : rcu_read_unlock();
605 : 0 : return size;
606 : : }
607 : : EXPORT_SYMBOL_GPL(gen_pool_size);
608 : :
609 : : /**
610 : : * gen_pool_set_algo - set the allocation algorithm
611 : : * @pool: pool to change allocation algorithm
612 : : * @algo: custom algorithm function
613 : : * @data: additional data used by @algo
614 : : *
615 : : * Call @algo for each memory allocation in the pool.
616 : : * If @algo is NULL use gen_pool_first_fit as default
617 : : * memory allocation function.
618 : : */
619 : 404 : void gen_pool_set_algo(struct gen_pool *pool, genpool_algo_t algo, void *data)
620 : : {
621 : : rcu_read_lock();
622 : :
623 : 404 : pool->algo = algo;
624 [ - + ]: 404 : if (!pool->algo)
625 : 0 : pool->algo = gen_pool_first_fit;
626 : :
627 : 404 : pool->data = data;
628 : :
629 : : rcu_read_unlock();
630 : 404 : }
631 : : EXPORT_SYMBOL(gen_pool_set_algo);
632 : :
633 : : /**
634 : : * gen_pool_first_fit - find the first available region
635 : : * of memory matching the size requirement (no alignment constraint)
636 : : * @map: The address to base the search on
637 : : * @size: The bitmap size in bits
638 : : * @start: The bitnumber to start searching at
639 : : * @nr: The number of zeroed bits we're looking for
640 : : * @data: additional data - unused
641 : : * @pool: pool to find the fit region memory from
642 : : */
643 : 0 : unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size,
644 : : unsigned long start, unsigned int nr, void *data,
645 : : struct gen_pool *pool, unsigned long start_addr)
646 : : {
647 : 0 : return bitmap_find_next_zero_area(map, size, start, nr, 0);
648 : : }
649 : : EXPORT_SYMBOL(gen_pool_first_fit);
650 : :
651 : : /**
652 : : * gen_pool_first_fit_align - find the first available region
653 : : * of memory matching the size requirement (alignment constraint)
654 : : * @map: The address to base the search on
655 : : * @size: The bitmap size in bits
656 : : * @start: The bitnumber to start searching at
657 : : * @nr: The number of zeroed bits we're looking for
658 : : * @data: data for alignment
659 : : * @pool: pool to get order from
660 : : */
661 : 0 : unsigned long gen_pool_first_fit_align(unsigned long *map, unsigned long size,
662 : : unsigned long start, unsigned int nr, void *data,
663 : : struct gen_pool *pool, unsigned long start_addr)
664 : : {
665 : : struct genpool_data_align *alignment;
666 : : unsigned long align_mask, align_off;
667 : : int order;
668 : :
669 : : alignment = data;
670 : 0 : order = pool->min_alloc_order;
671 : 0 : align_mask = ((alignment->align + (1UL << order) - 1) >> order) - 1;
672 : 0 : align_off = (start_addr & (alignment->align - 1)) >> order;
673 : :
674 : 0 : return bitmap_find_next_zero_area_off(map, size, start, nr,
675 : : align_mask, align_off);
676 : : }
677 : : EXPORT_SYMBOL(gen_pool_first_fit_align);
678 : :
679 : : /**
680 : : * gen_pool_fixed_alloc - reserve a specific region
681 : : * @map: The address to base the search on
682 : : * @size: The bitmap size in bits
683 : : * @start: The bitnumber to start searching at
684 : : * @nr: The number of zeroed bits we're looking for
685 : : * @data: data for alignment
686 : : * @pool: pool to get order from
687 : : */
688 : 0 : unsigned long gen_pool_fixed_alloc(unsigned long *map, unsigned long size,
689 : : unsigned long start, unsigned int nr, void *data,
690 : : struct gen_pool *pool, unsigned long start_addr)
691 : : {
692 : : struct genpool_data_fixed *fixed_data;
693 : : int order;
694 : : unsigned long offset_bit;
695 : : unsigned long start_bit;
696 : :
697 : : fixed_data = data;
698 : 0 : order = pool->min_alloc_order;
699 : 0 : offset_bit = fixed_data->offset >> order;
700 [ # # # # ]: 0 : if (WARN_ON(fixed_data->offset & ((1UL << order) - 1)))
701 : : return size;
702 : :
703 : 0 : start_bit = bitmap_find_next_zero_area(map, size,
704 : : start + offset_bit, nr, 0);
705 [ # # ]: 0 : if (start_bit != offset_bit)
706 : : start_bit = size;
707 : 0 : return start_bit;
708 : : }
709 : : EXPORT_SYMBOL(gen_pool_fixed_alloc);
710 : :
711 : : /**
712 : : * gen_pool_first_fit_order_align - find the first available region
713 : : * of memory matching the size requirement. The region will be aligned
714 : : * to the order of the size specified.
715 : : * @map: The address to base the search on
716 : : * @size: The bitmap size in bits
717 : : * @start: The bitnumber to start searching at
718 : : * @nr: The number of zeroed bits we're looking for
719 : : * @data: additional data - unused
720 : : * @pool: pool to find the fit region memory from
721 : : */
722 : 50942 : unsigned long gen_pool_first_fit_order_align(unsigned long *map,
723 : : unsigned long size, unsigned long start,
724 : : unsigned int nr, void *data, struct gen_pool *pool,
725 : : unsigned long start_addr)
726 : : {
727 [ - + # # : 101884 : unsigned long align_mask = roundup_pow_of_two(nr) - 1;
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728 : :
729 : 50942 : return bitmap_find_next_zero_area(map, size, start, nr, align_mask);
730 : : }
731 : : EXPORT_SYMBOL(gen_pool_first_fit_order_align);
732 : :
733 : : /**
734 : : * gen_pool_best_fit - find the best fitting region of memory
735 : : * macthing the size requirement (no alignment constraint)
736 : : * @map: The address to base the search on
737 : : * @size: The bitmap size in bits
738 : : * @start: The bitnumber to start searching at
739 : : * @nr: The number of zeroed bits we're looking for
740 : : * @data: additional data - unused
741 : : * @pool: pool to find the fit region memory from
742 : : *
743 : : * Iterate over the bitmap to find the smallest free region
744 : : * which we can allocate the memory.
745 : : */
746 : 0 : unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
747 : : unsigned long start, unsigned int nr, void *data,
748 : : struct gen_pool *pool, unsigned long start_addr)
749 : : {
750 : : unsigned long start_bit = size;
751 : 0 : unsigned long len = size + 1;
752 : : unsigned long index;
753 : :
754 : : index = bitmap_find_next_zero_area(map, size, start, nr, 0);
755 : :
756 [ # # ]: 0 : while (index < size) {
757 : 0 : int next_bit = find_next_bit(map, size, index + nr);
758 [ # # ]: 0 : if ((next_bit - index) < len) {
759 : : len = next_bit - index;
760 : : start_bit = index;
761 [ # # ]: 0 : if (len == nr)
762 : 0 : return start_bit;
763 : : }
764 : 0 : index = bitmap_find_next_zero_area(map, size,
765 : 0 : next_bit + 1, nr, 0);
766 : : }
767 : :
768 : 0 : return start_bit;
769 : : }
770 : : EXPORT_SYMBOL(gen_pool_best_fit);
771 : :
772 : 0 : static void devm_gen_pool_release(struct device *dev, void *res)
773 : : {
774 : 0 : gen_pool_destroy(*(struct gen_pool **)res);
775 : 0 : }
776 : :
777 : 0 : static int devm_gen_pool_match(struct device *dev, void *res, void *data)
778 : : {
779 : : struct gen_pool **p = res;
780 : :
781 : : /* NULL data matches only a pool without an assigned name */
782 [ # # # # ]: 0 : if (!data && !(*p)->name)
783 : : return 1;
784 : :
785 [ # # # # ]: 0 : if (!data || !(*p)->name)
786 : : return 0;
787 : :
788 : 0 : return !strcmp((*p)->name, data);
789 : : }
790 : :
791 : : /**
792 : : * gen_pool_get - Obtain the gen_pool (if any) for a device
793 : : * @dev: device to retrieve the gen_pool from
794 : : * @name: name of a gen_pool or NULL, identifies a particular gen_pool on device
795 : : *
796 : : * Returns the gen_pool for the device if one is present, or NULL.
797 : : */
798 : 0 : struct gen_pool *gen_pool_get(struct device *dev, const char *name)
799 : : {
800 : : struct gen_pool **p;
801 : :
802 : 0 : p = devres_find(dev, devm_gen_pool_release, devm_gen_pool_match,
803 : : (void *)name);
804 [ # # # # : 0 : if (!p)
# # ]
805 : : return NULL;
806 : 0 : return *p;
807 : : }
808 : : EXPORT_SYMBOL_GPL(gen_pool_get);
809 : :
810 : : /**
811 : : * devm_gen_pool_create - managed gen_pool_create
812 : : * @dev: device that provides the gen_pool
813 : : * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
814 : : * @nid: node selector for allocated gen_pool, %NUMA_NO_NODE for all nodes
815 : : * @name: name of a gen_pool or NULL, identifies a particular gen_pool on device
816 : : *
817 : : * Create a new special memory pool that can be used to manage special purpose
818 : : * memory not managed by the regular kmalloc/kfree interface. The pool will be
819 : : * automatically destroyed by the device management code.
820 : : */
821 : 0 : struct gen_pool *devm_gen_pool_create(struct device *dev, int min_alloc_order,
822 : : int nid, const char *name)
823 : : {
824 : : struct gen_pool **ptr, *pool;
825 : : const char *pool_name = NULL;
826 : :
827 : : /* Check that genpool to be created is uniquely addressed on device */
828 [ # # ]: 0 : if (gen_pool_get(dev, name))
829 : : return ERR_PTR(-EINVAL);
830 : :
831 [ # # ]: 0 : if (name) {
832 : 0 : pool_name = kstrdup_const(name, GFP_KERNEL);
833 [ # # ]: 0 : if (!pool_name)
834 : : return ERR_PTR(-ENOMEM);
835 : : }
836 : :
837 : : ptr = devres_alloc(devm_gen_pool_release, sizeof(*ptr), GFP_KERNEL);
838 [ # # ]: 0 : if (!ptr)
839 : : goto free_pool_name;
840 : :
841 : 0 : pool = gen_pool_create(min_alloc_order, nid);
842 [ # # ]: 0 : if (!pool)
843 : : goto free_devres;
844 : :
845 : 0 : *ptr = pool;
846 : 0 : pool->name = pool_name;
847 : 0 : devres_add(dev, ptr);
848 : :
849 : 0 : return pool;
850 : :
851 : : free_devres:
852 : 0 : devres_free(ptr);
853 : : free_pool_name:
854 : 0 : kfree_const(pool_name);
855 : :
856 : 0 : return ERR_PTR(-ENOMEM);
857 : : }
858 : : EXPORT_SYMBOL(devm_gen_pool_create);
859 : :
860 : : #ifdef CONFIG_OF
861 : : /**
862 : : * of_gen_pool_get - find a pool by phandle property
863 : : * @np: device node
864 : : * @propname: property name containing phandle(s)
865 : : * @index: index into the phandle array
866 : : *
867 : : * Returns the pool that contains the chunk starting at the physical
868 : : * address of the device tree node pointed at by the phandle property,
869 : : * or NULL if not found.
870 : : */
871 : 0 : struct gen_pool *of_gen_pool_get(struct device_node *np,
872 : : const char *propname, int index)
873 : : {
874 : : struct platform_device *pdev;
875 : : struct device_node *np_pool, *parent;
876 : 0 : const char *name = NULL;
877 : : struct gen_pool *pool = NULL;
878 : :
879 : 0 : np_pool = of_parse_phandle(np, propname, index);
880 [ # # ]: 0 : if (!np_pool)
881 : : return NULL;
882 : :
883 : 0 : pdev = of_find_device_by_node(np_pool);
884 [ # # ]: 0 : if (!pdev) {
885 : : /* Check if named gen_pool is created by parent node device */
886 : 0 : parent = of_get_parent(np_pool);
887 : 0 : pdev = of_find_device_by_node(parent);
888 : 0 : of_node_put(parent);
889 : :
890 : 0 : of_property_read_string(np_pool, "label", &name);
891 [ # # ]: 0 : if (!name)
892 : 0 : name = np_pool->name;
893 : : }
894 [ # # ]: 0 : if (pdev)
895 : 0 : pool = gen_pool_get(&pdev->dev, name);
896 : 0 : of_node_put(np_pool);
897 : :
898 : 0 : return pool;
899 : : }
900 : : EXPORT_SYMBOL_GPL(of_gen_pool_get);
901 : : #endif /* CONFIG_OF */
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