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- /*
- * Basic general purpose allocator for managing special purpose
- * memory, for example, memory that is not managed by the regular
- * kmalloc/kfree interface. Uses for this includes on-device special
- * memory, uncached memory etc.
- *
- * It is safe to use the allocator in NMI handlers and other special
- * unblockable contexts that could otherwise deadlock on locks. This
- * is implemented by using atomic operations and retries on any
- * conflicts. The disadvantage is that there may be livelocks in
- * extreme cases. For better scalability, one allocator can be used
- * for each CPU.
- *
- * The lockless operation only works if there is enough memory
- * available. If new memory is added to the pool a lock has to be
- * still taken. So any user relying on locklessness has to ensure
- * that sufficient memory is preallocated.
- *
- * The basic atomic operation of this allocator is cmpxchg on long.
- * On architectures that don't have NMI-safe cmpxchg implementation,
- * the allocator can NOT be used in NMI handler. So code uses the
- * allocator in NMI handler should depend on
- * CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG.
- *
- * Copyright 2005 (C) Jes Sorensen <jes@trained-monkey.org>
- *
- * This source code is licensed under the GNU General Public License,
- * Version 2. See the file COPYING for more details.
- */
- #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_device.h>
- static inline size_t chunk_size(const struct gen_pool_chunk *chunk)
- {
- return chunk->end_addr - chunk->start_addr + 1;
- }
- static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
- {
- unsigned long val, nval;
- nval = *addr;
- do {
- val = nval;
- if (val & mask_to_set)
- return -EBUSY;
- cpu_relax();
- } while ((nval = cmpxchg(addr, val, val | mask_to_set)) != val);
- return 0;
- }
- static int clear_bits_ll(unsigned long *addr, unsigned long mask_to_clear)
- {
- unsigned long val, nval;
- nval = *addr;
- do {
- val = nval;
- if ((val & mask_to_clear) != mask_to_clear)
- return -EBUSY;
- cpu_relax();
- } while ((nval = cmpxchg(addr, val, val & ~mask_to_clear)) != val);
- 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 int bitmap_set_ll(unsigned long *map, int start, int nr)
- {
- unsigned long *p = map + BIT_WORD(start);
- const int 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 >= 0) {
- 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 int bitmap_clear_ll(unsigned long *map, int start, int nr)
- {
- unsigned long *p = map + BIT_WORD(start);
- const int 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 >= 0) {
- 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_virt - 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
- *
- * 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_virt(struct gen_pool *pool, unsigned long virt, phys_addr_t phys,
- size_t size, int nid)
- {
- struct gen_pool_chunk *chunk;
- int nbits = size >> pool->min_alloc_order;
- int nbytes = sizeof(struct gen_pool_chunk) +
- BITS_TO_LONGS(nbits) * sizeof(long);
- chunk = kzalloc_node(nbytes, GFP_KERNEL, nid);
- if (unlikely(chunk == NULL))
- return -ENOMEM;
- chunk->phys_addr = phys;
- chunk->start_addr = virt;
- chunk->end_addr = virt + size - 1;
- 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_virt);
- /**
- * 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;
- int 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_next_bit(chunk->bits, end_bit, 0);
- BUG_ON(bit < end_bit);
- kfree(chunk);
- }
- kfree_const(pool->name);
- kfree(pool);
- }
- EXPORT_SYMBOL(gen_pool_destroy);
- /**
- * gen_pool_alloc - allocate special memory from the pool
- * @pool: pool to allocate from
- * @size: number of bytes to allocate from the pool
- *
- * 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(struct gen_pool *pool, size_t size)
- {
- return gen_pool_alloc_algo(pool, size, pool->algo, pool->data);
- }
- EXPORT_SYMBOL(gen_pool_alloc);
- /**
- * gen_pool_alloc_algo - 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
- *
- * 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(struct gen_pool *pool, size_t size,
- genpool_algo_t algo, void *data)
- {
- struct gen_pool_chunk *chunk;
- unsigned long addr = 0;
- int order = pool->min_alloc_order;
- int nbits, start_bit, end_bit, remain;
- #ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
- BUG_ON(in_nmi());
- #endif
- 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);
- 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);
- break;
- }
- rcu_read_unlock();
- return addr;
- }
- EXPORT_SYMBOL(gen_pool_alloc_algo);
- /**
- * 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.
- */
- void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
- {
- unsigned long vaddr;
- if (!pool)
- return NULL;
- vaddr = gen_pool_alloc(pool, size);
- if (!vaddr)
- return NULL;
- if (dma)
- *dma = gen_pool_virt_to_phys(pool, vaddr);
- return (void *)vaddr;
- }
- EXPORT_SYMBOL(gen_pool_dma_alloc);
- /**
- * gen_pool_free - 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
- *
- * 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(struct gen_pool *pool, unsigned long addr, size_t size)
- {
- struct gen_pool_chunk *chunk;
- int order = pool->min_alloc_order;
- int start_bit, nbits, remain;
- #ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
- BUG_ON(in_nmi());
- #endif
- 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);
- rcu_read_unlock();
- return;
- }
- }
- rcu_read_unlock();
- BUG();
- }
- EXPORT_SYMBOL(gen_pool_free);
- /**
- * 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);
- /**
- * addr_in_gen_pool - 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 addr_in_gen_pool(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;
- }
- /**
- * 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
- */
- unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size,
- unsigned long start, unsigned int nr, void *data,
- struct gen_pool *pool)
- {
- 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
- */
- 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)
- {
- struct genpool_data_align *alignment;
- unsigned long align_mask;
- int order;
- alignment = data;
- order = pool->min_alloc_order;
- align_mask = ((alignment->align + (1UL << order) - 1) >> order) - 1;
- return bitmap_find_next_zero_area(map, size, start, nr, align_mask);
- }
- 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
- */
- unsigned long gen_pool_fixed_alloc(unsigned long *map, unsigned long size,
- unsigned long start, unsigned int nr, void *data,
- struct gen_pool *pool)
- {
- 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
- */
- 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 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
- * macthing 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
- *
- * 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_bit = size;
- unsigned long len = size + 1;
- unsigned long index;
- index = bitmap_find_next_zero_area(map, size, start, nr, 0);
- while (index < size) {
- int 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 = np_pool->name;
- }
- if (pdev)
- pool = gen_pool_get(&pdev->dev, name);
- of_node_put(np_pool);
- return pool;
- }
- EXPORT_SYMBOL_GPL(of_gen_pool_get);
- #endif /* CONFIG_OF */
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