blob: 0a1139644d328a92ae346ee6fa723d7e18085c75 [file] [log] [blame]
Jes Sorensenf14f75b2005-06-21 17:15:02 -07001/*
Huang Ying7f184272011-07-13 13:14:24 +08002 * Basic general purpose allocator for managing special purpose
3 * memory, for example, memory that is not managed by the regular
4 * kmalloc/kfree interface. Uses for this includes on-device special
5 * memory, uncached memory etc.
6 *
7 * It is safe to use the allocator in NMI handlers and other special
8 * unblockable contexts that could otherwise deadlock on locks. This
9 * is implemented by using atomic operations and retries on any
10 * conflicts. The disadvantage is that there may be livelocks in
11 * extreme cases. For better scalability, one allocator can be used
12 * for each CPU.
13 *
14 * The lockless operation only works if there is enough memory
15 * available. If new memory is added to the pool a lock has to be
16 * still taken. So any user relying on locklessness has to ensure
17 * that sufficient memory is preallocated.
18 *
19 * The basic atomic operation of this allocator is cmpxchg on long.
20 * On architectures that don't have NMI-safe cmpxchg implementation,
21 * the allocator can NOT be used in NMI handler. So code uses the
22 * allocator in NMI handler should depend on
23 * CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG.
Jes Sorensenf14f75b2005-06-21 17:15:02 -070024 *
Jes Sorensenf14f75b2005-06-21 17:15:02 -070025 * Copyright 2005 (C) Jes Sorensen <jes@trained-monkey.org>
26 *
27 * This source code is licensed under the GNU General Public License,
28 * Version 2. See the file COPYING for more details.
29 */
30
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090031#include <linux/slab.h>
Paul Gortmaker8bc3bcc2011-11-16 21:29:17 -050032#include <linux/export.h>
Akinobu Mita243797f2009-12-15 16:48:31 -080033#include <linux/bitmap.h>
Huang Ying7f184272011-07-13 13:14:24 +080034#include <linux/rculist.h>
35#include <linux/interrupt.h>
Jes Sorensenf14f75b2005-06-21 17:15:02 -070036#include <linux/genalloc.h>
Philipp Zabel9375db02013-04-29 16:17:10 -070037#include <linux/of_device.h>
Jes Sorensenf14f75b2005-06-21 17:15:02 -070038
Joonyoung Shim674470d2013-09-11 14:21:43 -070039static inline size_t chunk_size(const struct gen_pool_chunk *chunk)
40{
41 return chunk->end_addr - chunk->start_addr + 1;
42}
43
Huang Ying7f184272011-07-13 13:14:24 +080044static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
45{
46 unsigned long val, nval;
47
48 nval = *addr;
49 do {
50 val = nval;
51 if (val & mask_to_set)
52 return -EBUSY;
53 cpu_relax();
54 } while ((nval = cmpxchg(addr, val, val | mask_to_set)) != val);
55
56 return 0;
57}
58
59static int clear_bits_ll(unsigned long *addr, unsigned long mask_to_clear)
60{
61 unsigned long val, nval;
62
63 nval = *addr;
64 do {
65 val = nval;
66 if ((val & mask_to_clear) != mask_to_clear)
67 return -EBUSY;
68 cpu_relax();
69 } while ((nval = cmpxchg(addr, val, val & ~mask_to_clear)) != val);
70
71 return 0;
72}
73
74/*
75 * bitmap_set_ll - set the specified number of bits at the specified position
76 * @map: pointer to a bitmap
77 * @start: a bit position in @map
78 * @nr: number of bits to set
79 *
80 * Set @nr bits start from @start in @map lock-lessly. Several users
81 * can set/clear the same bitmap simultaneously without lock. If two
82 * users set the same bit, one user will return remain bits, otherwise
83 * return 0.
84 */
85static int bitmap_set_ll(unsigned long *map, int start, int nr)
86{
87 unsigned long *p = map + BIT_WORD(start);
88 const int size = start + nr;
89 int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
90 unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
91
92 while (nr - bits_to_set >= 0) {
93 if (set_bits_ll(p, mask_to_set))
94 return nr;
95 nr -= bits_to_set;
96 bits_to_set = BITS_PER_LONG;
97 mask_to_set = ~0UL;
98 p++;
99 }
100 if (nr) {
101 mask_to_set &= BITMAP_LAST_WORD_MASK(size);
102 if (set_bits_ll(p, mask_to_set))
103 return nr;
104 }
105
106 return 0;
107}
108
109/*
110 * bitmap_clear_ll - clear the specified number of bits at the specified position
111 * @map: pointer to a bitmap
112 * @start: a bit position in @map
113 * @nr: number of bits to set
114 *
115 * Clear @nr bits start from @start in @map lock-lessly. Several users
116 * can set/clear the same bitmap simultaneously without lock. If two
117 * users clear the same bit, one user will return remain bits,
118 * otherwise return 0.
119 */
120static int bitmap_clear_ll(unsigned long *map, int start, int nr)
121{
122 unsigned long *p = map + BIT_WORD(start);
123 const int size = start + nr;
124 int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
125 unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
126
127 while (nr - bits_to_clear >= 0) {
128 if (clear_bits_ll(p, mask_to_clear))
129 return nr;
130 nr -= bits_to_clear;
131 bits_to_clear = BITS_PER_LONG;
132 mask_to_clear = ~0UL;
133 p++;
134 }
135 if (nr) {
136 mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
137 if (clear_bits_ll(p, mask_to_clear))
138 return nr;
139 }
140
141 return 0;
142}
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700143
Dean Nelsona58cbd72006-10-02 02:17:01 -0700144/**
145 * gen_pool_create - create a new special memory pool
Dean Nelson929f9722006-06-23 02:03:21 -0700146 * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
147 * @nid: node id of the node the pool structure should be allocated on, or -1
Dean Nelsona58cbd72006-10-02 02:17:01 -0700148 *
149 * Create a new special memory pool that can be used to manage special purpose
150 * memory not managed by the regular kmalloc/kfree interface.
Dean Nelson929f9722006-06-23 02:03:21 -0700151 */
152struct gen_pool *gen_pool_create(int min_alloc_order, int nid)
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700153{
Dean Nelson929f9722006-06-23 02:03:21 -0700154 struct gen_pool *pool;
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700155
Dean Nelson929f9722006-06-23 02:03:21 -0700156 pool = kmalloc_node(sizeof(struct gen_pool), GFP_KERNEL, nid);
157 if (pool != NULL) {
Huang Ying7f184272011-07-13 13:14:24 +0800158 spin_lock_init(&pool->lock);
Dean Nelson929f9722006-06-23 02:03:21 -0700159 INIT_LIST_HEAD(&pool->chunks);
160 pool->min_alloc_order = min_alloc_order;
Benjamin Gaignardca279cf2012-10-04 17:13:20 -0700161 pool->algo = gen_pool_first_fit;
162 pool->data = NULL;
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700163 pool->name = NULL;
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700164 }
Dean Nelson929f9722006-06-23 02:03:21 -0700165 return pool;
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700166}
167EXPORT_SYMBOL(gen_pool_create);
168
Dean Nelsona58cbd72006-10-02 02:17:01 -0700169/**
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700170 * gen_pool_add_virt - add a new chunk of special memory to the pool
Dean Nelson929f9722006-06-23 02:03:21 -0700171 * @pool: pool to add new memory chunk to
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700172 * @virt: virtual starting address of memory chunk to add to pool
173 * @phys: physical starting address of memory chunk to add to pool
Dean Nelson929f9722006-06-23 02:03:21 -0700174 * @size: size in bytes of the memory chunk to add to pool
175 * @nid: node id of the node the chunk structure and bitmap should be
176 * allocated on, or -1
Dean Nelsona58cbd72006-10-02 02:17:01 -0700177 *
178 * Add a new chunk of special memory to the specified pool.
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700179 *
180 * Returns 0 on success or a -ve errno on failure.
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700181 */
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700182int gen_pool_add_virt(struct gen_pool *pool, unsigned long virt, phys_addr_t phys,
183 size_t size, int nid)
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700184{
Dean Nelson929f9722006-06-23 02:03:21 -0700185 struct gen_pool_chunk *chunk;
186 int nbits = size >> pool->min_alloc_order;
187 int nbytes = sizeof(struct gen_pool_chunk) +
Thadeu Lima de Souza Cascardoeedce142012-10-25 13:37:51 -0700188 BITS_TO_LONGS(nbits) * sizeof(long);
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700189
Joe Perchesade34a32013-09-11 14:23:06 -0700190 chunk = kzalloc_node(nbytes, GFP_KERNEL, nid);
Dean Nelson929f9722006-06-23 02:03:21 -0700191 if (unlikely(chunk == NULL))
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700192 return -ENOMEM;
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700193
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700194 chunk->phys_addr = phys;
195 chunk->start_addr = virt;
Joonyoung Shim674470d2013-09-11 14:21:43 -0700196 chunk->end_addr = virt + size - 1;
Huang Ying7f184272011-07-13 13:14:24 +0800197 atomic_set(&chunk->avail, size);
Dean Nelson929f9722006-06-23 02:03:21 -0700198
Huang Ying7f184272011-07-13 13:14:24 +0800199 spin_lock(&pool->lock);
200 list_add_rcu(&chunk->next_chunk, &pool->chunks);
201 spin_unlock(&pool->lock);
Dean Nelson929f9722006-06-23 02:03:21 -0700202
203 return 0;
204}
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700205EXPORT_SYMBOL(gen_pool_add_virt);
206
207/**
208 * gen_pool_virt_to_phys - return the physical address of memory
209 * @pool: pool to allocate from
210 * @addr: starting address of memory
211 *
212 * Returns the physical address on success, or -1 on error.
213 */
214phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long addr)
215{
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700216 struct gen_pool_chunk *chunk;
Huang Ying7f184272011-07-13 13:14:24 +0800217 phys_addr_t paddr = -1;
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700218
Huang Ying7f184272011-07-13 13:14:24 +0800219 rcu_read_lock();
220 list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
Joonyoung Shim674470d2013-09-11 14:21:43 -0700221 if (addr >= chunk->start_addr && addr <= chunk->end_addr) {
Huang Ying7f184272011-07-13 13:14:24 +0800222 paddr = chunk->phys_addr + (addr - chunk->start_addr);
223 break;
224 }
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700225 }
Huang Ying7f184272011-07-13 13:14:24 +0800226 rcu_read_unlock();
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700227
Huang Ying7f184272011-07-13 13:14:24 +0800228 return paddr;
Jean-Christophe PLAGNIOL-VILLARD3c8f3702011-05-24 17:13:34 -0700229}
230EXPORT_SYMBOL(gen_pool_virt_to_phys);
Dean Nelson929f9722006-06-23 02:03:21 -0700231
Dean Nelsona58cbd72006-10-02 02:17:01 -0700232/**
233 * gen_pool_destroy - destroy a special memory pool
Steve Wise322acc92006-10-02 02:17:00 -0700234 * @pool: pool to destroy
Dean Nelsona58cbd72006-10-02 02:17:01 -0700235 *
236 * Destroy the specified special memory pool. Verifies that there are no
237 * outstanding allocations.
Steve Wise322acc92006-10-02 02:17:00 -0700238 */
239void gen_pool_destroy(struct gen_pool *pool)
240{
241 struct list_head *_chunk, *_next_chunk;
242 struct gen_pool_chunk *chunk;
243 int order = pool->min_alloc_order;
244 int bit, end_bit;
245
Steve Wise322acc92006-10-02 02:17:00 -0700246 list_for_each_safe(_chunk, _next_chunk, &pool->chunks) {
247 chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
248 list_del(&chunk->next_chunk);
249
Joonyoung Shim674470d2013-09-11 14:21:43 -0700250 end_bit = chunk_size(chunk) >> order;
Steve Wise322acc92006-10-02 02:17:00 -0700251 bit = find_next_bit(chunk->bits, end_bit, 0);
252 BUG_ON(bit < end_bit);
253
254 kfree(chunk);
255 }
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700256 kfree_const(pool->name);
Steve Wise322acc92006-10-02 02:17:00 -0700257 kfree(pool);
Steve Wise322acc92006-10-02 02:17:00 -0700258}
259EXPORT_SYMBOL(gen_pool_destroy);
260
Dean Nelsona58cbd72006-10-02 02:17:01 -0700261/**
262 * gen_pool_alloc - allocate special memory from the pool
Dean Nelson929f9722006-06-23 02:03:21 -0700263 * @pool: pool to allocate from
264 * @size: number of bytes to allocate from the pool
Dean Nelsona58cbd72006-10-02 02:17:01 -0700265 *
266 * Allocate the requested number of bytes from the specified pool.
Benjamin Gaignardca279cf2012-10-04 17:13:20 -0700267 * Uses the pool allocation function (with first-fit algorithm by default).
268 * Can not be used in NMI handler on architectures without
269 * NMI-safe cmpxchg implementation.
Dean Nelson929f9722006-06-23 02:03:21 -0700270 */
271unsigned long gen_pool_alloc(struct gen_pool *pool, size_t size)
272{
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800273 return gen_pool_alloc_algo(pool, size, pool->algo, pool->data);
274}
275EXPORT_SYMBOL(gen_pool_alloc);
276
277/**
278 * gen_pool_alloc_algo - allocate special memory from the pool
279 * @pool: pool to allocate from
280 * @size: number of bytes to allocate from the pool
281 * @algo: algorithm passed from caller
282 * @data: data passed to algorithm
283 *
284 * Allocate the requested number of bytes from the specified pool.
285 * Uses the pool allocation function (with first-fit algorithm by default).
286 * Can not be used in NMI handler on architectures without
287 * NMI-safe cmpxchg implementation.
288 */
289unsigned long gen_pool_alloc_algo(struct gen_pool *pool, size_t size,
290 genpool_algo_t algo, void *data)
291{
Dean Nelson929f9722006-06-23 02:03:21 -0700292 struct gen_pool_chunk *chunk;
Huang Ying7f184272011-07-13 13:14:24 +0800293 unsigned long addr = 0;
Dean Nelson929f9722006-06-23 02:03:21 -0700294 int order = pool->min_alloc_order;
Huang Ying7f184272011-07-13 13:14:24 +0800295 int nbits, start_bit = 0, end_bit, remain;
296
297#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
298 BUG_ON(in_nmi());
299#endif
Dean Nelson929f9722006-06-23 02:03:21 -0700300
301 if (size == 0)
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700302 return 0;
303
Dean Nelson929f9722006-06-23 02:03:21 -0700304 nbits = (size + (1UL << order) - 1) >> order;
Huang Ying7f184272011-07-13 13:14:24 +0800305 rcu_read_lock();
306 list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
307 if (size > atomic_read(&chunk->avail))
308 continue;
Dean Nelson929f9722006-06-23 02:03:21 -0700309
Joonyoung Shim674470d2013-09-11 14:21:43 -0700310 end_bit = chunk_size(chunk) >> order;
Huang Ying7f184272011-07-13 13:14:24 +0800311retry:
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800312 start_bit = algo(chunk->bits, end_bit, start_bit,
313 nbits, data, pool);
Huang Ying7f184272011-07-13 13:14:24 +0800314 if (start_bit >= end_bit)
Akinobu Mita243797f2009-12-15 16:48:31 -0800315 continue;
Huang Ying7f184272011-07-13 13:14:24 +0800316 remain = bitmap_set_ll(chunk->bits, start_bit, nbits);
317 if (remain) {
318 remain = bitmap_clear_ll(chunk->bits, start_bit,
319 nbits - remain);
320 BUG_ON(remain);
321 goto retry;
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700322 }
Akinobu Mita243797f2009-12-15 16:48:31 -0800323
324 addr = chunk->start_addr + ((unsigned long)start_bit << order);
Huang Ying7f184272011-07-13 13:14:24 +0800325 size = nbits << order;
326 atomic_sub(size, &chunk->avail);
327 break;
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700328 }
Huang Ying7f184272011-07-13 13:14:24 +0800329 rcu_read_unlock();
330 return addr;
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700331}
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800332EXPORT_SYMBOL(gen_pool_alloc_algo);
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700333
Dean Nelsona58cbd72006-10-02 02:17:01 -0700334/**
Nicolin Chen684f0d32013-11-12 15:09:52 -0800335 * gen_pool_dma_alloc - allocate special memory from the pool for DMA usage
336 * @pool: pool to allocate from
337 * @size: number of bytes to allocate from the pool
Lad, Prabhakar0368dfd2014-01-29 14:05:37 -0800338 * @dma: dma-view physical address return value. Use NULL if unneeded.
Nicolin Chen684f0d32013-11-12 15:09:52 -0800339 *
340 * Allocate the requested number of bytes from the specified pool.
341 * Uses the pool allocation function (with first-fit algorithm by default).
342 * Can not be used in NMI handler on architectures without
343 * NMI-safe cmpxchg implementation.
344 */
345void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
346{
347 unsigned long vaddr;
348
349 if (!pool)
350 return NULL;
351
352 vaddr = gen_pool_alloc(pool, size);
353 if (!vaddr)
354 return NULL;
355
Lad, Prabhakar0368dfd2014-01-29 14:05:37 -0800356 if (dma)
357 *dma = gen_pool_virt_to_phys(pool, vaddr);
Nicolin Chen684f0d32013-11-12 15:09:52 -0800358
359 return (void *)vaddr;
360}
361EXPORT_SYMBOL(gen_pool_dma_alloc);
362
363/**
Dean Nelsona58cbd72006-10-02 02:17:01 -0700364 * gen_pool_free - free allocated special memory back to the pool
Dean Nelson929f9722006-06-23 02:03:21 -0700365 * @pool: pool to free to
366 * @addr: starting address of memory to free back to pool
367 * @size: size in bytes of memory to free
Dean Nelsona58cbd72006-10-02 02:17:01 -0700368 *
Huang Ying7f184272011-07-13 13:14:24 +0800369 * Free previously allocated special memory back to the specified
370 * pool. Can not be used in NMI handler on architectures without
371 * NMI-safe cmpxchg implementation.
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700372 */
Dean Nelson929f9722006-06-23 02:03:21 -0700373void gen_pool_free(struct gen_pool *pool, unsigned long addr, size_t size)
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700374{
Dean Nelson929f9722006-06-23 02:03:21 -0700375 struct gen_pool_chunk *chunk;
Dean Nelson929f9722006-06-23 02:03:21 -0700376 int order = pool->min_alloc_order;
Huang Ying7f184272011-07-13 13:14:24 +0800377 int start_bit, nbits, remain;
378
379#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
380 BUG_ON(in_nmi());
381#endif
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700382
Dean Nelson929f9722006-06-23 02:03:21 -0700383 nbits = (size + (1UL << order) - 1) >> order;
Huang Ying7f184272011-07-13 13:14:24 +0800384 rcu_read_lock();
385 list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
Joonyoung Shim674470d2013-09-11 14:21:43 -0700386 if (addr >= chunk->start_addr && addr <= chunk->end_addr) {
387 BUG_ON(addr + size - 1 > chunk->end_addr);
Huang Ying7f184272011-07-13 13:14:24 +0800388 start_bit = (addr - chunk->start_addr) >> order;
389 remain = bitmap_clear_ll(chunk->bits, start_bit, nbits);
390 BUG_ON(remain);
391 size = nbits << order;
392 atomic_add(size, &chunk->avail);
393 rcu_read_unlock();
394 return;
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700395 }
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700396 }
Huang Ying7f184272011-07-13 13:14:24 +0800397 rcu_read_unlock();
398 BUG();
Jes Sorensenf14f75b2005-06-21 17:15:02 -0700399}
400EXPORT_SYMBOL(gen_pool_free);
Huang Ying7f184272011-07-13 13:14:24 +0800401
402/**
403 * gen_pool_for_each_chunk - call func for every chunk of generic memory pool
404 * @pool: the generic memory pool
405 * @func: func to call
406 * @data: additional data used by @func
407 *
408 * Call @func for every chunk of generic memory pool. The @func is
409 * called with rcu_read_lock held.
410 */
411void gen_pool_for_each_chunk(struct gen_pool *pool,
412 void (*func)(struct gen_pool *pool, struct gen_pool_chunk *chunk, void *data),
413 void *data)
414{
415 struct gen_pool_chunk *chunk;
416
417 rcu_read_lock();
418 list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk)
419 func(pool, chunk, data);
420 rcu_read_unlock();
421}
422EXPORT_SYMBOL(gen_pool_for_each_chunk);
423
424/**
Laura Abbott9efb3a42014-10-09 15:26:38 -0700425 * addr_in_gen_pool - checks if an address falls within the range of a pool
426 * @pool: the generic memory pool
427 * @start: start address
428 * @size: size of the region
429 *
430 * Check if the range of addresses falls within the specified pool. Returns
431 * true if the entire range is contained in the pool and false otherwise.
432 */
433bool addr_in_gen_pool(struct gen_pool *pool, unsigned long start,
434 size_t size)
435{
436 bool found = false;
Toshi Kikuchiad3d5d22015-02-12 15:02:18 -0800437 unsigned long end = start + size - 1;
Laura Abbott9efb3a42014-10-09 15:26:38 -0700438 struct gen_pool_chunk *chunk;
439
440 rcu_read_lock();
441 list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk) {
442 if (start >= chunk->start_addr && start <= chunk->end_addr) {
443 if (end <= chunk->end_addr) {
444 found = true;
445 break;
446 }
447 }
448 }
449 rcu_read_unlock();
450 return found;
451}
452
453/**
Huang Ying7f184272011-07-13 13:14:24 +0800454 * gen_pool_avail - get available free space of the pool
455 * @pool: pool to get available free space
456 *
457 * Return available free space of the specified pool.
458 */
459size_t gen_pool_avail(struct gen_pool *pool)
460{
461 struct gen_pool_chunk *chunk;
462 size_t avail = 0;
463
464 rcu_read_lock();
465 list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk)
466 avail += atomic_read(&chunk->avail);
467 rcu_read_unlock();
468 return avail;
469}
470EXPORT_SYMBOL_GPL(gen_pool_avail);
471
472/**
473 * gen_pool_size - get size in bytes of memory managed by the pool
474 * @pool: pool to get size
475 *
476 * Return size in bytes of memory managed by the pool.
477 */
478size_t gen_pool_size(struct gen_pool *pool)
479{
480 struct gen_pool_chunk *chunk;
481 size_t size = 0;
482
483 rcu_read_lock();
484 list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk)
Joonyoung Shim674470d2013-09-11 14:21:43 -0700485 size += chunk_size(chunk);
Huang Ying7f184272011-07-13 13:14:24 +0800486 rcu_read_unlock();
487 return size;
488}
489EXPORT_SYMBOL_GPL(gen_pool_size);
Benjamin Gaignardca279cf2012-10-04 17:13:20 -0700490
491/**
492 * gen_pool_set_algo - set the allocation algorithm
493 * @pool: pool to change allocation algorithm
494 * @algo: custom algorithm function
495 * @data: additional data used by @algo
496 *
497 * Call @algo for each memory allocation in the pool.
498 * If @algo is NULL use gen_pool_first_fit as default
499 * memory allocation function.
500 */
501void gen_pool_set_algo(struct gen_pool *pool, genpool_algo_t algo, void *data)
502{
503 rcu_read_lock();
504
505 pool->algo = algo;
506 if (!pool->algo)
507 pool->algo = gen_pool_first_fit;
508
509 pool->data = data;
510
511 rcu_read_unlock();
512}
513EXPORT_SYMBOL(gen_pool_set_algo);
514
515/**
516 * gen_pool_first_fit - find the first available region
517 * of memory matching the size requirement (no alignment constraint)
518 * @map: The address to base the search on
519 * @size: The bitmap size in bits
520 * @start: The bitnumber to start searching at
521 * @nr: The number of zeroed bits we're looking for
522 * @data: additional data - unused
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800523 * @pool: pool to find the fit region memory from
Benjamin Gaignardca279cf2012-10-04 17:13:20 -0700524 */
525unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size,
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800526 unsigned long start, unsigned int nr, void *data,
527 struct gen_pool *pool)
Benjamin Gaignardca279cf2012-10-04 17:13:20 -0700528{
529 return bitmap_find_next_zero_area(map, size, start, nr, 0);
530}
531EXPORT_SYMBOL(gen_pool_first_fit);
532
533/**
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800534 * gen_pool_first_fit_align - find the first available region
535 * of memory matching the size requirement (alignment constraint)
536 * @map: The address to base the search on
537 * @size: The bitmap size in bits
538 * @start: The bitnumber to start searching at
539 * @nr: The number of zeroed bits we're looking for
540 * @data: data for alignment
541 * @pool: pool to get order from
542 */
543unsigned long gen_pool_first_fit_align(unsigned long *map, unsigned long size,
544 unsigned long start, unsigned int nr, void *data,
545 struct gen_pool *pool)
546{
547 struct genpool_data_align *alignment;
548 unsigned long align_mask;
549 int order;
550
551 alignment = data;
552 order = pool->min_alloc_order;
553 align_mask = ((alignment->align + (1UL << order) - 1) >> order) - 1;
554 return bitmap_find_next_zero_area(map, size, start, nr, align_mask);
555}
556EXPORT_SYMBOL(gen_pool_first_fit_align);
557
558/**
Zhao Qiangb26981c2015-11-30 10:48:53 +0800559 * gen_pool_fixed_alloc - reserve a specific region
560 * @map: The address to base the search on
561 * @size: The bitmap size in bits
562 * @start: The bitnumber to start searching at
563 * @nr: The number of zeroed bits we're looking for
564 * @data: data for alignment
565 * @pool: pool to get order from
566 */
567unsigned long gen_pool_fixed_alloc(unsigned long *map, unsigned long size,
568 unsigned long start, unsigned int nr, void *data,
569 struct gen_pool *pool)
570{
571 struct genpool_data_fixed *fixed_data;
572 int order;
573 unsigned long offset_bit;
574 unsigned long start_bit;
575
576 fixed_data = data;
577 order = pool->min_alloc_order;
578 offset_bit = fixed_data->offset >> order;
Zhao Qiang0e6e01f2015-11-30 10:48:54 +0800579 if (WARN_ON(fixed_data->offset & ((1UL << order) - 1)))
Zhao Qiangb26981c2015-11-30 10:48:53 +0800580 return size;
581
582 start_bit = bitmap_find_next_zero_area(map, size,
583 start + offset_bit, nr, 0);
584 if (start_bit != offset_bit)
585 start_bit = size;
586 return start_bit;
587}
588EXPORT_SYMBOL(gen_pool_fixed_alloc);
589
590/**
Laura Abbott505e3be2014-10-09 15:26:35 -0700591 * gen_pool_first_fit_order_align - find the first available region
592 * of memory matching the size requirement. The region will be aligned
593 * to the order of the size specified.
594 * @map: The address to base the search on
595 * @size: The bitmap size in bits
596 * @start: The bitnumber to start searching at
597 * @nr: The number of zeroed bits we're looking for
598 * @data: additional data - unused
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800599 * @pool: pool to find the fit region memory from
Laura Abbott505e3be2014-10-09 15:26:35 -0700600 */
601unsigned long gen_pool_first_fit_order_align(unsigned long *map,
602 unsigned long size, unsigned long start,
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800603 unsigned int nr, void *data, struct gen_pool *pool)
Laura Abbott505e3be2014-10-09 15:26:35 -0700604{
605 unsigned long align_mask = roundup_pow_of_two(nr) - 1;
606
607 return bitmap_find_next_zero_area(map, size, start, nr, align_mask);
608}
609EXPORT_SYMBOL(gen_pool_first_fit_order_align);
610
611/**
Benjamin Gaignardca279cf2012-10-04 17:13:20 -0700612 * gen_pool_best_fit - find the best fitting region of memory
613 * macthing the size requirement (no alignment constraint)
614 * @map: The address to base the search on
615 * @size: The bitmap size in bits
616 * @start: The bitnumber to start searching at
617 * @nr: The number of zeroed bits we're looking for
618 * @data: additional data - unused
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800619 * @pool: pool to find the fit region memory from
Benjamin Gaignardca279cf2012-10-04 17:13:20 -0700620 *
621 * Iterate over the bitmap to find the smallest free region
622 * which we can allocate the memory.
623 */
624unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
Zhao Qiangde2dd0e2015-11-30 10:48:52 +0800625 unsigned long start, unsigned int nr, void *data,
626 struct gen_pool *pool)
Benjamin Gaignardca279cf2012-10-04 17:13:20 -0700627{
628 unsigned long start_bit = size;
629 unsigned long len = size + 1;
630 unsigned long index;
631
632 index = bitmap_find_next_zero_area(map, size, start, nr, 0);
633
634 while (index < size) {
635 int next_bit = find_next_bit(map, size, index + nr);
636 if ((next_bit - index) < len) {
637 len = next_bit - index;
638 start_bit = index;
639 if (len == nr)
640 return start_bit;
641 }
642 index = bitmap_find_next_zero_area(map, size,
643 next_bit + 1, nr, 0);
644 }
645
646 return start_bit;
647}
648EXPORT_SYMBOL(gen_pool_best_fit);
Philipp Zabel9375db02013-04-29 16:17:10 -0700649
650static void devm_gen_pool_release(struct device *dev, void *res)
651{
652 gen_pool_destroy(*(struct gen_pool **)res);
653}
654
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700655static int devm_gen_pool_match(struct device *dev, void *res, void *data)
656{
657 struct gen_pool **p = res;
658
659 /* NULL data matches only a pool without an assigned name */
660 if (!data && !(*p)->name)
661 return 1;
662
663 if (!data || !(*p)->name)
664 return 0;
665
666 return !strcmp((*p)->name, data);
667}
668
Philipp Zabel9375db02013-04-29 16:17:10 -0700669/**
Vladimir Zapolskiy73858172015-09-04 15:47:43 -0700670 * gen_pool_get - Obtain the gen_pool (if any) for a device
671 * @dev: device to retrieve the gen_pool from
672 * @name: name of a gen_pool or NULL, identifies a particular gen_pool on device
673 *
674 * Returns the gen_pool for the device if one is present, or NULL.
675 */
676struct gen_pool *gen_pool_get(struct device *dev, const char *name)
677{
678 struct gen_pool **p;
679
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700680 p = devres_find(dev, devm_gen_pool_release, devm_gen_pool_match,
681 (void *)name);
Vladimir Zapolskiy73858172015-09-04 15:47:43 -0700682 if (!p)
683 return NULL;
684 return *p;
685}
686EXPORT_SYMBOL_GPL(gen_pool_get);
687
688/**
Philipp Zabel9375db02013-04-29 16:17:10 -0700689 * devm_gen_pool_create - managed gen_pool_create
690 * @dev: device that provides the gen_pool
691 * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
Vladimir Zapolskiy73858172015-09-04 15:47:43 -0700692 * @nid: node selector for allocated gen_pool, %NUMA_NO_NODE for all nodes
693 * @name: name of a gen_pool or NULL, identifies a particular gen_pool on device
Philipp Zabel9375db02013-04-29 16:17:10 -0700694 *
695 * Create a new special memory pool that can be used to manage special purpose
696 * memory not managed by the regular kmalloc/kfree interface. The pool will be
697 * automatically destroyed by the device management code.
698 */
699struct gen_pool *devm_gen_pool_create(struct device *dev, int min_alloc_order,
Vladimir Zapolskiy73858172015-09-04 15:47:43 -0700700 int nid, const char *name)
Philipp Zabel9375db02013-04-29 16:17:10 -0700701{
702 struct gen_pool **ptr, *pool;
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700703 const char *pool_name = NULL;
Philipp Zabel9375db02013-04-29 16:17:10 -0700704
Vladimir Zapolskiy73858172015-09-04 15:47:43 -0700705 /* Check that genpool to be created is uniquely addressed on device */
706 if (gen_pool_get(dev, name))
707 return ERR_PTR(-EINVAL);
708
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700709 if (name) {
710 pool_name = kstrdup_const(name, GFP_KERNEL);
711 if (!pool_name)
712 return ERR_PTR(-ENOMEM);
Philipp Zabel9375db02013-04-29 16:17:10 -0700713 }
714
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700715 ptr = devres_alloc(devm_gen_pool_release, sizeof(*ptr), GFP_KERNEL);
716 if (!ptr)
717 goto free_pool_name;
718
719 pool = gen_pool_create(min_alloc_order, nid);
720 if (!pool)
721 goto free_devres;
722
723 *ptr = pool;
724 pool->name = pool_name;
725 devres_add(dev, ptr);
726
Philipp Zabel9375db02013-04-29 16:17:10 -0700727 return pool;
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700728
729free_devres:
730 devres_free(ptr);
731free_pool_name:
732 kfree_const(pool_name);
733
734 return ERR_PTR(-ENOMEM);
Philipp Zabel9375db02013-04-29 16:17:10 -0700735}
Michal Simekb724aa22014-12-02 15:59:45 -0800736EXPORT_SYMBOL(devm_gen_pool_create);
Philipp Zabel9375db02013-04-29 16:17:10 -0700737
Philipp Zabel9375db02013-04-29 16:17:10 -0700738#ifdef CONFIG_OF
739/**
Vladimir Zapolskiyabdd4a72015-06-30 15:00:07 -0700740 * of_gen_pool_get - find a pool by phandle property
Philipp Zabel9375db02013-04-29 16:17:10 -0700741 * @np: device node
742 * @propname: property name containing phandle(s)
743 * @index: index into the phandle array
744 *
745 * Returns the pool that contains the chunk starting at the physical
746 * address of the device tree node pointed at by the phandle property,
747 * or NULL if not found.
748 */
Vladimir Zapolskiyabdd4a72015-06-30 15:00:07 -0700749struct gen_pool *of_gen_pool_get(struct device_node *np,
Philipp Zabel9375db02013-04-29 16:17:10 -0700750 const char *propname, int index)
751{
752 struct platform_device *pdev;
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700753 struct device_node *np_pool, *parent;
754 const char *name = NULL;
755 struct gen_pool *pool = NULL;
Philipp Zabel9375db02013-04-29 16:17:10 -0700756
757 np_pool = of_parse_phandle(np, propname, index);
758 if (!np_pool)
759 return NULL;
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700760
Philipp Zabel9375db02013-04-29 16:17:10 -0700761 pdev = of_find_device_by_node(np_pool);
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700762 if (!pdev) {
763 /* Check if named gen_pool is created by parent node device */
764 parent = of_get_parent(np_pool);
765 pdev = of_find_device_by_node(parent);
766 of_node_put(parent);
767
768 of_property_read_string(np_pool, "label", &name);
769 if (!name)
770 name = np_pool->name;
771 }
772 if (pdev)
773 pool = gen_pool_get(&pdev->dev, name);
Vladimir Zapolskiy6f3aabd2014-09-25 16:05:25 -0700774 of_node_put(np_pool);
Vladimir Zapolskiyc98c3632015-09-04 15:47:47 -0700775
776 return pool;
Philipp Zabel9375db02013-04-29 16:17:10 -0700777}
Vladimir Zapolskiyabdd4a72015-06-30 15:00:07 -0700778EXPORT_SYMBOL_GPL(of_gen_pool_get);
Philipp Zabel9375db02013-04-29 16:17:10 -0700779#endif /* CONFIG_OF */