| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* |
| * 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. |
| */ |
| |
| |
| #ifndef __GENALLOC_H__ |
| #define __GENALLOC_H__ |
| |
| #include <linux/types.h> |
| #include <linux/spinlock_types.h> |
| #include <linux/atomic.h> |
| |
| struct device; |
| struct device_node; |
| struct gen_pool; |
| |
| /** |
| * typedef genpool_algo_t: Allocation callback function type definition |
| * @map: Pointer to bitmap |
| * @size: The bitmap size in bits |
| * @start: The bitnumber to start searching at |
| * @nr: The number of zeroed bits we're looking for |
| * @data: optional additional data used by the callback |
| * @pool: the pool being allocated from |
| */ |
| typedef unsigned long (*genpool_algo_t)(unsigned long *map, |
| unsigned long size, |
| unsigned long start, |
| unsigned int nr, |
| void *data, struct gen_pool *pool, |
| unsigned long start_addr); |
| |
| /* |
| * General purpose special memory pool descriptor. |
| */ |
| struct gen_pool { |
| spinlock_t lock; |
| struct list_head chunks; /* list of chunks in this pool */ |
| int min_alloc_order; /* minimum allocation order */ |
| |
| genpool_algo_t algo; /* allocation function */ |
| void *data; |
| |
| const char *name; |
| }; |
| |
| /* |
| * General purpose special memory pool chunk descriptor. |
| */ |
| struct gen_pool_chunk { |
| struct list_head next_chunk; /* next chunk in pool */ |
| atomic_long_t avail; |
| phys_addr_t phys_addr; /* physical starting address of memory chunk */ |
| void *owner; /* private data to retrieve at alloc time */ |
| unsigned long start_addr; /* start address of memory chunk */ |
| unsigned long end_addr; /* end address of memory chunk (inclusive) */ |
| unsigned long bits[]; /* bitmap for allocating memory chunk */ |
| }; |
| |
| /* |
| * gen_pool data descriptor for gen_pool_first_fit_align. |
| */ |
| struct genpool_data_align { |
| int align; /* alignment by bytes for starting address */ |
| }; |
| |
| /* |
| * gen_pool data descriptor for gen_pool_fixed_alloc. |
| */ |
| struct genpool_data_fixed { |
| unsigned long offset; /* The offset of the specific region */ |
| }; |
| |
| extern struct gen_pool *gen_pool_create(int, int); |
| extern phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long); |
| extern int gen_pool_add_owner(struct gen_pool *, unsigned long, phys_addr_t, |
| size_t, int, void *); |
| |
| static inline int gen_pool_add_virt(struct gen_pool *pool, unsigned long addr, |
| phys_addr_t phys, size_t size, int nid) |
| { |
| return gen_pool_add_owner(pool, addr, phys, size, nid, NULL); |
| } |
| |
| /** |
| * gen_pool_add - add a new chunk of special memory to the pool |
| * @pool: pool to add new memory chunk to |
| * @addr: 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. |
| */ |
| static inline int gen_pool_add(struct gen_pool *pool, unsigned long addr, |
| size_t size, int nid) |
| { |
| return gen_pool_add_virt(pool, addr, -1, size, nid); |
| } |
| extern void gen_pool_destroy(struct gen_pool *); |
| unsigned long gen_pool_alloc_algo_owner(struct gen_pool *pool, size_t size, |
| genpool_algo_t algo, void *data, void **owner); |
| |
| static inline unsigned long gen_pool_alloc_owner(struct gen_pool *pool, |
| size_t size, void **owner) |
| { |
| return gen_pool_alloc_algo_owner(pool, size, pool->algo, pool->data, |
| owner); |
| } |
| |
| static inline unsigned long gen_pool_alloc_algo(struct gen_pool *pool, |
| size_t size, genpool_algo_t algo, void *data) |
| { |
| return gen_pool_alloc_algo_owner(pool, size, algo, data, NULL); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline unsigned long gen_pool_alloc(struct gen_pool *pool, size_t size) |
| { |
| return gen_pool_alloc_algo(pool, size, pool->algo, pool->data); |
| } |
| |
| extern void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, |
| dma_addr_t *dma); |
| extern void *gen_pool_dma_alloc_algo(struct gen_pool *pool, size_t size, |
| dma_addr_t *dma, genpool_algo_t algo, void *data); |
| extern void *gen_pool_dma_alloc_align(struct gen_pool *pool, size_t size, |
| dma_addr_t *dma, int align); |
| extern void *gen_pool_dma_zalloc(struct gen_pool *pool, size_t size, dma_addr_t *dma); |
| extern void *gen_pool_dma_zalloc_algo(struct gen_pool *pool, size_t size, |
| dma_addr_t *dma, genpool_algo_t algo, void *data); |
| extern void *gen_pool_dma_zalloc_align(struct gen_pool *pool, size_t size, |
| dma_addr_t *dma, int align); |
| extern void gen_pool_free_owner(struct gen_pool *pool, unsigned long addr, |
| size_t size, void **owner); |
| static inline void gen_pool_free(struct gen_pool *pool, unsigned long addr, |
| size_t size) |
| { |
| gen_pool_free_owner(pool, addr, size, NULL); |
| } |
| |
| extern void gen_pool_for_each_chunk(struct gen_pool *, |
| void (*)(struct gen_pool *, struct gen_pool_chunk *, void *), void *); |
| extern size_t gen_pool_avail(struct gen_pool *); |
| extern size_t gen_pool_size(struct gen_pool *); |
| |
| extern void gen_pool_set_algo(struct gen_pool *pool, genpool_algo_t algo, |
| void *data); |
| |
| extern 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); |
| |
| extern 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); |
| |
| extern 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); |
| |
| |
| extern 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); |
| |
| extern 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); |
| |
| |
| extern struct gen_pool *devm_gen_pool_create(struct device *dev, |
| int min_alloc_order, int nid, const char *name); |
| extern struct gen_pool *gen_pool_get(struct device *dev, const char *name); |
| |
| extern bool gen_pool_has_addr(struct gen_pool *pool, unsigned long start, |
| size_t size); |
| |
| #ifdef CONFIG_OF |
| extern struct gen_pool *of_gen_pool_get(struct device_node *np, |
| const char *propname, int index); |
| #else |
| static inline struct gen_pool *of_gen_pool_get(struct device_node *np, |
| const char *propname, int index) |
| { |
| return NULL; |
| } |
| #endif |
| #endif /* __GENALLOC_H__ */ |