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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#include <linux/slab.h>#include <linux/export.h>#include <linux/bitmap.h>#include <linux/rculist.h>#include <linux/interrupt.h>#include <linux/genalloc.h>#include <linux/of.h>#include <linux/of_platform.h>#include <linux/platform_device.h>#include <linux/vmalloc.h>
static inline size_t chunk_size(const struct gen_pool_chunk *chunk){ return chunk->end_addr - chunk->start_addr + 1;}
static inline intset_bits_ll(unsigned long *addr, unsigned long mask_to_set){ unsigned long val = READ_ONCE(*addr);
do { if (val & mask_to_set) return -EBUSY; cpu_relax(); } while (!try_cmpxchg(addr, &val, val | mask_to_set));
return 0;}
static inline intclear_bits_ll(unsigned long *addr, unsigned long mask_to_clear){ unsigned long val = READ_ONCE(*addr);
do { if ((val & mask_to_clear) != mask_to_clear) return -EBUSY; cpu_relax(); } while (!try_cmpxchg(addr, &val, val & ~mask_to_clear));
return 0;}
/* * bitmap_set_ll - set the specified number of bits at the specified position * @map: pointer to a bitmap * @start: a bit position in @map * @nr: number of bits to set * * Set @nr bits start from @start in @map lock-lessly. Several users * can set/clear the same bitmap simultaneously without lock. If two * users set the same bit, one user will return remain bits, otherwise * return 0. */static unsigned longbitmap_set_ll(unsigned long *map, unsigned long start, unsigned long nr){ unsigned long *p = map + BIT_WORD(start); const unsigned long size = start + nr; int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
while (nr >= bits_to_set) { if (set_bits_ll(p, mask_to_set)) return nr; nr -= bits_to_set; bits_to_set = BITS_PER_LONG; mask_to_set = ~0UL; p++; } if (nr) { mask_to_set &= BITMAP_LAST_WORD_MASK(size); if (set_bits_ll(p, mask_to_set)) return nr; }
return 0;}
/* * bitmap_clear_ll - clear the specified number of bits at the specified position * @map: pointer to a bitmap * @start: a bit position in @map * @nr: number of bits to set * * Clear @nr bits start from @start in @map lock-lessly. Several users * can set/clear the same bitmap simultaneously without lock. If two * users clear the same bit, one user will return remain bits, * otherwise return 0. */static unsigned longbitmap_clear_ll(unsigned long *map, unsigned long start, unsigned long nr){ unsigned long *p = map + BIT_WORD(start); const unsigned long size = start + nr; int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
while (nr >= bits_to_clear) { if (clear_bits_ll(p, mask_to_clear)) return nr; nr -= bits_to_clear; bits_to_clear = BITS_PER_LONG; mask_to_clear = ~0UL; p++; } if (nr) { mask_to_clear &= BITMAP_LAST_WORD_MASK(size); if (clear_bits_ll(p, mask_to_clear)) return nr; }
return 0;}
/** * gen_pool_create - create a new special memory pool * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents * @nid: node id of the node the pool structure should be allocated on, or -1 * * Create a new special memory pool that can be used to manage special purpose * memory not managed by the regular kmalloc/kfree interface. */struct gen_pool *gen_pool_create(int min_alloc_order, int nid){ struct gen_pool *pool;
pool = kmalloc_node(sizeof(struct gen_pool), GFP_KERNEL, nid); if (pool != NULL) { spin_lock_init(&pool->lock); INIT_LIST_HEAD(&pool->chunks); pool->min_alloc_order = min_alloc_order; pool->algo = gen_pool_first_fit; pool->data = NULL; pool->name = NULL; } return pool;}EXPORT_SYMBOL(gen_pool_create);
/** * gen_pool_add_owner- add a new chunk of special memory to the pool * @pool: pool to add new memory chunk to * @virt: virtual starting address of memory chunk to add to pool * @phys: physical starting address of memory chunk to add to pool * @size: size in bytes of the memory chunk to add to pool * @nid: node id of the node the chunk structure and bitmap should be * allocated on, or -1 * @owner: private data the publisher would like to recall at alloc time * * Add a new chunk of special memory to the specified pool. * * Returns 0 on success or a -ve errno on failure. */int gen_pool_add_owner(struct gen_pool *pool, unsigned long virt, phys_addr_t phys, size_t size, int nid, void *owner){ struct gen_pool_chunk *chunk; unsigned long nbits = size >> pool->min_alloc_order; unsigned long nbytes = sizeof(struct gen_pool_chunk) + BITS_TO_LONGS(nbits) * sizeof(long);
chunk = vzalloc_node(nbytes, nid); if (unlikely(chunk == NULL)) return -ENOMEM;
chunk->phys_addr = phys; chunk->start_addr = virt; chunk->end_addr = virt + size - 1; chunk->owner = owner; atomic_long_set(&chunk->avail, size);
spin_lock(&pool->lock); list_add_rcu(&chunk->next_chunk, &pool->chunks); spin_unlock(&pool->lock);
return 0;}EXPORT_SYMBOL(gen_pool_add_owner);
/** * gen_pool_virt_to_phys - return the physical address of memory * @pool: pool to allocate from * @addr: starting address of memory * * Returns the physical address on success, or -1 on error. */phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long addr){ struct gen_pool_chunk *chunk; phys_addr_t paddr = -1;
rcu_read_lock(); list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) { if (addr >= chunk->start_addr && addr <= chunk->end_addr) { paddr = chunk->phys_addr + (addr - chunk->start_addr); break; } } rcu_read_unlock();
return paddr;}EXPORT_SYMBOL(gen_pool_virt_to_phys);
/** * gen_pool_destroy - destroy a special memory pool * @pool: pool to destroy * * Destroy the specified special memory pool. Verifies that there are no * outstanding allocations. */void gen_pool_destroy(struct gen_pool *pool){ struct list_head *_chunk, *_next_chunk; struct gen_pool_chunk *chunk; int order = pool->min_alloc_order; unsigned long bit, end_bit;
list_for_each_safe(_chunk, _next_chunk, &pool->chunks) { chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk); list_del(&chunk->next_chunk);
end_bit = chunk_size(chunk) >> order; bit = find_first_bit(chunk->bits, end_bit); BUG_ON(bit < end_bit);
vfree(chunk); } kfree_const(pool->name); kfree(pool);}EXPORT_SYMBOL(gen_pool_destroy);
/** * gen_pool_alloc_algo_owner - allocate special memory from the pool * @pool: pool to allocate from * @size: number of bytes to allocate from the pool * @algo: algorithm passed from caller * @data: data passed to algorithm * @owner: optionally retrieve the chunk owner * * Allocate the requested number of bytes from the specified pool. * Uses the pool allocation function (with first-fit algorithm by default). * Can not be used in NMI handler on architectures without * NMI-safe cmpxchg implementation. */unsigned long gen_pool_alloc_algo_owner(struct gen_pool *pool, size_t size, genpool_algo_t algo, void *data, void **owner){ struct gen_pool_chunk *chunk; unsigned long addr = 0; int order = pool->min_alloc_order; unsigned long nbits, start_bit, end_bit, remain;
#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG BUG_ON(in_nmi());#endif
if (owner) *owner = NULL;
if (size == 0) return 0;
nbits = (size + (1UL << order) - 1) >> order; rcu_read_lock(); list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) { if (size > atomic_long_read(&chunk->avail)) continue;
start_bit = 0; end_bit = chunk_size(chunk) >> order;retry: start_bit = algo(chunk->bits, end_bit, start_bit, nbits, data, pool, chunk->start_addr); if (start_bit >= end_bit) continue; remain = bitmap_set_ll(chunk->bits, start_bit, nbits); if (remain) { remain = bitmap_clear_ll(chunk->bits, start_bit, nbits - remain); BUG_ON(remain); goto retry; }
addr = chunk->start_addr + ((unsigned long)start_bit << order); size = nbits << order; atomic_long_sub(size, &chunk->avail); if (owner) *owner = chunk->owner; break; } rcu_read_unlock(); return addr;}EXPORT_SYMBOL(gen_pool_alloc_algo_owner);
/** * gen_pool_dma_alloc - allocate special memory from the pool for DMA usage * @pool: pool to allocate from * @size: number of bytes to allocate from the pool * @dma: dma-view physical address return value. Use %NULL if unneeded. * * Allocate the requested number of bytes from the specified pool. * Uses the pool allocation function (with first-fit algorithm by default). * Can not be used in NMI handler on architectures without * NMI-safe cmpxchg implementation. * * Return: virtual address of the allocated memory, or %NULL on failure */void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma){ return gen_pool_dma_alloc_algo(pool, size, dma, pool->algo, pool->data);}EXPORT_SYMBOL(gen_pool_dma_alloc);
/** * gen_pool_dma_alloc_algo - allocate special memory from the pool for DMA * usage with the given pool algorithm * @pool: pool to allocate from * @size: number of bytes to allocate from the pool * @dma: DMA-view physical address return value. Use %NULL if unneeded. * @algo: algorithm passed from caller * @data: data passed to algorithm * * Allocate the requested number of bytes from the specified pool. Uses the * given pool allocation function. Can not be used in NMI handler on * architectures without NMI-safe cmpxchg implementation. * * Return: virtual address of the allocated memory, or %NULL on failure */void *gen_pool_dma_alloc_algo(struct gen_pool *pool, size_t size, dma_addr_t *dma, genpool_algo_t algo, void *data){ unsigned long vaddr;
if (!pool) return NULL;
vaddr = gen_pool_alloc_algo(pool, size, algo, data); if (!vaddr) return NULL;
if (dma) *dma = gen_pool_virt_to_phys(pool, vaddr);
return (void *)vaddr;}EXPORT_SYMBOL(gen_pool_dma_alloc_algo);
/** * gen_pool_dma_alloc_align - allocate special memory from the pool for DMA * usage with the given alignment * @pool: pool to allocate from * @size: number of bytes to allocate from the pool * @dma: DMA-view physical address return value. Use %NULL if unneeded. * @align: alignment in bytes for starting address * * Allocate the requested number bytes from the specified pool, with the given * alignment restriction. Can not be used in NMI handler on architectures * without NMI-safe cmpxchg implementation. * * Return: virtual address of the allocated memory, or %NULL on failure */void *gen_pool_dma_alloc_align(struct gen_pool *pool, size_t size, dma_addr_t *dma, int align){ struct genpool_data_align data = { .align = align };
return gen_pool_dma_alloc_algo(pool, size, dma, gen_pool_first_fit_align, &data);}EXPORT_SYMBOL(gen_pool_dma_alloc_align);
/** * gen_pool_dma_zalloc - allocate special zeroed memory from the pool for * DMA usage * @pool: pool to allocate from * @size: number of bytes to allocate from the pool * @dma: dma-view physical address return value. Use %NULL if unneeded. * * Allocate the requested number of zeroed bytes from the specified pool. * Uses the pool allocation function (with first-fit algorithm by default). * Can not be used in NMI handler on architectures without * NMI-safe cmpxchg implementation. * * Return: virtual address of the allocated zeroed memory, or %NULL on failure */void *gen_pool_dma_zalloc(struct gen_pool *pool, size_t size, dma_addr_t *dma){ return gen_pool_dma_zalloc_algo(pool, size, dma, pool->algo, pool->data);}EXPORT_SYMBOL(gen_pool_dma_zalloc);
/** * gen_pool_dma_zalloc_algo - allocate special zeroed memory from the pool for * DMA usage with the given pool algorithm * @pool: pool to allocate from * @size: number of bytes to allocate from the pool * @dma: DMA-view physical address return value. Use %NULL if unneeded. * @algo: algorithm passed from caller * @data: data passed to algorithm * * Allocate the requested number of zeroed bytes from the specified pool. Uses * the given pool allocation function. Can not be used in NMI handler on * architectures without NMI-safe cmpxchg implementation. * * Return: virtual address of the allocated zeroed memory, or %NULL on failure */void *gen_pool_dma_zalloc_algo(struct gen_pool *pool, size_t size, dma_addr_t *dma, genpool_algo_t algo, void *data){ void *vaddr = gen_pool_dma_alloc_algo(pool, size, dma, algo, data);
if (vaddr) memset(vaddr, 0, size);
return vaddr;}EXPORT_SYMBOL(gen_pool_dma_zalloc_algo);
/** * gen_pool_dma_zalloc_align - allocate special zeroed memory from the pool for * DMA usage with the given alignment * @pool: pool to allocate from * @size: number of bytes to allocate from the pool * @dma: DMA-view physical address return value. Use %NULL if unneeded. * @align: alignment in bytes for starting address * * Allocate the requested number of zeroed bytes from the specified pool, * with the given alignment restriction. Can not be used in NMI handler on * architectures without NMI-safe cmpxchg implementation. * * Return: virtual address of the allocated zeroed memory, or %NULL on failure */void *gen_pool_dma_zalloc_align(struct gen_pool *pool, size_t size, dma_addr_t *dma, int align){ struct genpool_data_align data = { .align = align };
return gen_pool_dma_zalloc_algo(pool, size, dma, gen_pool_first_fit_align, &data);}EXPORT_SYMBOL(gen_pool_dma_zalloc_align);
/** * gen_pool_free_owner - free allocated special memory back to the pool * @pool: pool to free to * @addr: starting address of memory to free back to pool * @size: size in bytes of memory to free * @owner: private data stashed at gen_pool_add() time * * Free previously allocated special memory back to the specified * pool. Can not be used in NMI handler on architectures without * NMI-safe cmpxchg implementation. */void gen_pool_free_owner(struct gen_pool *pool, unsigned long addr, size_t size, void **owner){ struct gen_pool_chunk *chunk; int order = pool->min_alloc_order; unsigned long start_bit, nbits, remain;
#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG BUG_ON(in_nmi());#endif
if (owner) *owner = NULL;
nbits = (size + (1UL << order) - 1) >> order; rcu_read_lock(); list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) { if (addr >= chunk->start_addr && addr <= chunk->end_addr) { BUG_ON(addr + size - 1 > chunk->end_addr); start_bit = (addr - chunk->start_addr) >> order; remain = bitmap_clear_ll(chunk->bits, start_bit, nbits); BUG_ON(remain); size = nbits << order; atomic_long_add(size, &chunk->avail); if (owner) *owner = chunk->owner; rcu_read_unlock(); return; } } rcu_read_unlock(); BUG();}EXPORT_SYMBOL(gen_pool_free_owner);
/** * gen_pool_for_each_chunk - call func for every chunk of generic memory pool * @pool: the generic memory pool * @func: func to call * @data: additional data used by @func * * Call @func for every chunk of generic memory pool. The @func is * called with rcu_read_lock held. */void gen_pool_for_each_chunk(struct gen_pool *pool, void (*func)(struct gen_pool *pool, struct gen_pool_chunk *chunk, void *data), void *data){ struct gen_pool_chunk *chunk;
rcu_read_lock(); list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk) func(pool, chunk, data); rcu_read_unlock();}EXPORT_SYMBOL(gen_pool_for_each_chunk);
/** * gen_pool_has_addr - checks if an address falls within the range of a pool * @pool: the generic memory pool * @start: start address * @size: size of the region * * Check if the range of addresses falls within the specified pool. Returns * true if the entire range is contained in the pool and false otherwise. */bool gen_pool_has_addr(struct gen_pool *pool, unsigned long start, size_t size){ bool found = false; unsigned long end = start + size - 1; struct gen_pool_chunk *chunk;
rcu_read_lock(); list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk) { if (start >= chunk->start_addr && start <= chunk->end_addr) { if (end <= chunk->end_addr) { found = true; break; } } } rcu_read_unlock(); return found;}EXPORT_SYMBOL(gen_pool_has_addr);
/** * gen_pool_avail - get available free space of the pool * @pool: pool to get available free space * * Return available free space of the specified pool. */size_t gen_pool_avail(struct gen_pool *pool){ struct gen_pool_chunk *chunk; size_t avail = 0;
rcu_read_lock(); list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) avail += atomic_long_read(&chunk->avail); rcu_read_unlock(); return avail;}EXPORT_SYMBOL_GPL(gen_pool_avail);
/** * gen_pool_size - get size in bytes of memory managed by the pool * @pool: pool to get size * * Return size in bytes of memory managed by the pool. */size_t gen_pool_size(struct gen_pool *pool){ struct gen_pool_chunk *chunk; size_t size = 0;
rcu_read_lock(); list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) size += chunk_size(chunk); rcu_read_unlock(); return size;}EXPORT_SYMBOL_GPL(gen_pool_size);
/** * gen_pool_set_algo - set the allocation algorithm * @pool: pool to change allocation algorithm * @algo: custom algorithm function * @data: additional data used by @algo * * Call @algo for each memory allocation in the pool. * If @algo is NULL use gen_pool_first_fit as default * memory allocation function. */void gen_pool_set_algo(struct gen_pool *pool, genpool_algo_t algo, void *data){ rcu_read_lock();
pool->algo = algo; if (!pool->algo) pool->algo = gen_pool_first_fit;
pool->data = data;
rcu_read_unlock();}EXPORT_SYMBOL(gen_pool_set_algo);
/** * gen_pool_first_fit - find the first available region * of memory matching the size requirement (no alignment constraint) * @map: The address to base the search on * @size: The bitmap size in bits * @start: The bitnumber to start searching at * @nr: The number of zeroed bits we're looking for * @data: additional data - unused * @pool: pool to find the fit region memory from * @start_addr: not used in this function */unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data, struct gen_pool *pool, unsigned long start_addr){ return bitmap_find_next_zero_area(map, size, start, nr, 0);}EXPORT_SYMBOL(gen_pool_first_fit);
/** * gen_pool_first_fit_align - find the first available region * of memory matching the size requirement (alignment constraint) * @map: The address to base the search on * @size: The bitmap size in bits * @start: The bitnumber to start searching at * @nr: The number of zeroed bits we're looking for * @data: data for alignment * @pool: pool to get order from * @start_addr: start addr of alloction chunk */unsigned long gen_pool_first_fit_align(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data, struct gen_pool *pool, unsigned long start_addr){ struct genpool_data_align *alignment; unsigned long align_mask, align_off; int order;
alignment = data; order = pool->min_alloc_order; align_mask = ((alignment->align + (1UL << order) - 1) >> order) - 1; align_off = (start_addr & (alignment->align - 1)) >> order;
return bitmap_find_next_zero_area_off(map, size, start, nr, align_mask, align_off);}EXPORT_SYMBOL(gen_pool_first_fit_align);
/** * gen_pool_fixed_alloc - reserve a specific region * @map: The address to base the search on * @size: The bitmap size in bits * @start: The bitnumber to start searching at * @nr: The number of zeroed bits we're looking for * @data: data for alignment * @pool: pool to get order from * @start_addr: not used in this function */unsigned long gen_pool_fixed_alloc(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data, struct gen_pool *pool, unsigned long start_addr){ struct genpool_data_fixed *fixed_data; int order; unsigned long offset_bit; unsigned long start_bit;
fixed_data = data; order = pool->min_alloc_order; offset_bit = fixed_data->offset >> order; if (WARN_ON(fixed_data->offset & ((1UL << order) - 1))) return size;
start_bit = bitmap_find_next_zero_area(map, size, start + offset_bit, nr, 0); if (start_bit != offset_bit) start_bit = size; return start_bit;}EXPORT_SYMBOL(gen_pool_fixed_alloc);
/** * gen_pool_first_fit_order_align - find the first available region * of memory matching the size requirement. The region will be aligned * to the order of the size specified. * @map: The address to base the search on * @size: The bitmap size in bits * @start: The bitnumber to start searching at * @nr: The number of zeroed bits we're looking for * @data: additional data - unused * @pool: pool to find the fit region memory from * @start_addr: not used in this function */unsigned long gen_pool_first_fit_order_align(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data, struct gen_pool *pool, unsigned long start_addr){ unsigned long align_mask = roundup_pow_of_two(nr) - 1;
return bitmap_find_next_zero_area(map, size, start, nr, align_mask);}EXPORT_SYMBOL(gen_pool_first_fit_order_align);
/** * gen_pool_best_fit - find the best fitting region of memory * matching the size requirement (no alignment constraint) * @map: The address to base the search on * @size: The bitmap size in bits * @start: The bitnumber to start searching at * @nr: The number of zeroed bits we're looking for * @data: additional data - unused * @pool: pool to find the fit region memory from * @start_addr: not used in this function * * Iterate over the bitmap to find the smallest free region * which we can allocate the memory. */unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data, struct gen_pool *pool, unsigned long start_addr){ unsigned long start_bit = size; unsigned long len = size + 1; unsigned long index;
index = bitmap_find_next_zero_area(map, size, start, nr, 0);
while (index < size) { unsigned long next_bit = find_next_bit(map, size, index + nr); if ((next_bit - index) < len) { len = next_bit - index; start_bit = index; if (len == nr) return start_bit; } index = bitmap_find_next_zero_area(map, size, next_bit + 1, nr, 0); }
return start_bit;}EXPORT_SYMBOL(gen_pool_best_fit);
static void devm_gen_pool_release(struct device *dev, void *res){ gen_pool_destroy(*(struct gen_pool **)res);}
static int devm_gen_pool_match(struct device *dev, void *res, void *data){ struct gen_pool **p = res;
/* NULL data matches only a pool without an assigned name */ if (!data && !(*p)->name) return 1;
if (!data || !(*p)->name) return 0;
return !strcmp((*p)->name, data);}
/** * gen_pool_get - Obtain the gen_pool (if any) for a device * @dev: device to retrieve the gen_pool from * @name: name of a gen_pool or NULL, identifies a particular gen_pool on device * * Returns the gen_pool for the device if one is present, or NULL. */struct gen_pool *gen_pool_get(struct device *dev, const char *name){ struct gen_pool **p;
p = devres_find(dev, devm_gen_pool_release, devm_gen_pool_match, (void *)name); if (!p) return NULL; return *p;}EXPORT_SYMBOL_GPL(gen_pool_get);
/** * devm_gen_pool_create - managed gen_pool_create * @dev: device that provides the gen_pool * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents * @nid: node selector for allocated gen_pool, %NUMA_NO_NODE for all nodes * @name: name of a gen_pool or NULL, identifies a particular gen_pool on device * * Create a new special memory pool that can be used to manage special purpose * memory not managed by the regular kmalloc/kfree interface. The pool will be * automatically destroyed by the device management code. */struct gen_pool *devm_gen_pool_create(struct device *dev, int min_alloc_order, int nid, const char *name){ struct gen_pool **ptr, *pool; const char *pool_name = NULL;
/* Check that genpool to be created is uniquely addressed on device */ if (gen_pool_get(dev, name)) return ERR_PTR(-EINVAL);
if (name) { pool_name = kstrdup_const(name, GFP_KERNEL); if (!pool_name) return ERR_PTR(-ENOMEM); }
ptr = devres_alloc(devm_gen_pool_release, sizeof(*ptr), GFP_KERNEL); if (!ptr) goto free_pool_name;
pool = gen_pool_create(min_alloc_order, nid); if (!pool) goto free_devres;
*ptr = pool; pool->name = pool_name; devres_add(dev, ptr);
return pool;
free_devres: devres_free(ptr);free_pool_name: kfree_const(pool_name);
return ERR_PTR(-ENOMEM);}EXPORT_SYMBOL(devm_gen_pool_create);
#ifdef CONFIG_OF/** * of_gen_pool_get - find a pool by phandle property * @np: device node * @propname: property name containing phandle(s) * @index: index into the phandle array * * Returns the pool that contains the chunk starting at the physical * address of the device tree node pointed at by the phandle property, * or NULL if not found. */struct gen_pool *of_gen_pool_get(struct device_node *np, const char *propname, int index){ struct platform_device *pdev; struct device_node *np_pool, *parent; const char *name = NULL; struct gen_pool *pool = NULL;
np_pool = of_parse_phandle(np, propname, index); if (!np_pool) return NULL;
pdev = of_find_device_by_node(np_pool); if (!pdev) { /* Check if named gen_pool is created by parent node device */ parent = of_get_parent(np_pool); pdev = of_find_device_by_node(parent); of_node_put(parent);
of_property_read_string(np_pool, "label", &name); if (!name) name = of_node_full_name(np_pool); } if (pdev) { pool = gen_pool_get(&pdev->dev, name); put_device(&pdev->dev); }
of_node_put(np_pool);
return pool;}EXPORT_SYMBOL_GPL(of_gen_pool_get);#endif /* CONFIG_OF */