1 /* 2 * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved. 3 * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. 4 * 5 * Permission to use, copy, modify, and/or distribute this software for 6 * any purpose with or without fee is hereby granted, provided that the 7 * above copyright notice and this permission notice appear in all 8 * copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL 11 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED 12 * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE 13 * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 14 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 15 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 16 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 17 * PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 /** 21 * DOC: qdf_flex_mem (flexibly sized memory allocator) 22 * QCA driver framework (QDF) flex mem APIs 23 * 24 * A flex memory allocator is a memory pool which not only dynamically expands, 25 * but also dynamically reduces as well. Benefits over full dynamic memory 26 * allocation are amoritized allocation cost, and reduced memory fragmentation. 27 * 28 * The allocator consists of 3 parts: the pool, segments, and items. Items are 29 * the smallest chuncks of memory that are handed out via the alloc call, and 30 * are all of a uniform size. Segments are groups of items, representing the 31 * smallest amount of memory that can be dynamically allocated or freed. A pool 32 * is simply a collection of segments. 33 */ 34 35 #ifndef __QDF_FLEX_MEM_H 36 #define __QDF_FLEX_MEM_H 37 38 #include "qdf_list.h" 39 #include "qdf_lock.h" 40 41 #define QDF_FM_BITMAP uint32_t 42 #define QDF_FM_BITMAP_BITS (sizeof(QDF_FM_BITMAP) * 8) 43 44 /** 45 * qdf_flex_mem_pool - a pool of memory segments 46 * @seg_list: the list containing the memory segments 47 * @lock: spinlock for protecting internal data structures 48 * @reduction_limit: the minimum number of segments to keep during reduction 49 * @item_size: the size of the items the pool will allocate 50 */ 51 struct qdf_flex_mem_pool { 52 qdf_list_t seg_list; 53 struct qdf_spinlock lock; 54 uint16_t reduction_limit; 55 uint16_t item_size; 56 }; 57 58 /** 59 * qdf_flex_mem_segment - a memory pool segment 60 * @node: the list node for membership in the memory pool 61 * @dynamic: true if this segment was dynamically allocated 62 * @used_bitmap: bitmap for tracking which items in the segment are in use 63 * @bytes: raw memory for allocating items from 64 */ 65 struct qdf_flex_mem_segment { 66 qdf_list_node_t node; 67 bool dynamic; 68 QDF_FM_BITMAP used_bitmap; 69 uint8_t *bytes; 70 }; 71 72 /** 73 * DEFINE_QDF_FLEX_MEM_POOL() - define a new flex mem pool with one segment 74 * @name: the name of the pool variable 75 * @size_of_item: size of the items the pool will allocate 76 * @rm_limit: min number of segments to keep during reduction 77 */ 78 #define DEFINE_QDF_FLEX_MEM_POOL(name, size_of_item, rm_limit) \ 79 struct qdf_flex_mem_pool name; \ 80 uint8_t __ ## name ## _head_bytes[QDF_FM_BITMAP_BITS * (size_of_item)];\ 81 struct qdf_flex_mem_segment __ ## name ## _head = { \ 82 .node = QDF_LIST_NODE_INIT_SINGLE( \ 83 QDF_LIST_ANCHOR(name.seg_list)), \ 84 .bytes = __ ## name ## _head_bytes, \ 85 }; \ 86 struct qdf_flex_mem_pool name = { \ 87 .seg_list = QDF_LIST_INIT_SINGLE(__ ## name ## _head.node), \ 88 .reduction_limit = (rm_limit), \ 89 .item_size = (size_of_item), \ 90 } 91 92 /** 93 * qdf_flex_mem_init() - initialize a qdf_flex_mem_pool 94 * @pool: the pool to initialize 95 * 96 * Return: None 97 */ 98 void qdf_flex_mem_init(struct qdf_flex_mem_pool *pool); 99 100 /** 101 * qdf_flex_mem_deinit() - deinitialize a qdf_flex_mem_pool 102 * @pool: the pool to deinitialize 103 * 104 * Return: None 105 */ 106 void qdf_flex_mem_deinit(struct qdf_flex_mem_pool *pool); 107 108 /** 109 * qdf_flex_mem_alloc() - logically allocate memory from the pool 110 * @pool: the pool to allocate from 111 * 112 * This function returns any unused item from any existing segment in the pool. 113 * If there are no unused items in the pool, a new segment is dynamically 114 * allocated to service the request. The size of the allocated memory is the 115 * size originally used to create the pool. 116 * 117 * Return: Point to newly allocated memory, NULL on failure 118 */ 119 void *qdf_flex_mem_alloc(struct qdf_flex_mem_pool *pool); 120 121 /** 122 * qdf_flex_mem_free() - logically frees @ptr from the pool 123 * @pool: the pool to return the memory to 124 * @ptr: a pointer received via a call to qdf_flex_mem_alloc() 125 * 126 * This function marks the item corresponding to @ptr as unused. If that item 127 * was the last used item in the segment it belongs to, and the segment was 128 * dynamically allocated, the segment will be freed. 129 * 130 * Return: None 131 */ 132 void qdf_flex_mem_free(struct qdf_flex_mem_pool *pool, void *ptr); 133 134 #endif /* __QDF_FLEX_MEM_H */ 135