1 /* 2 * Copyright (c) 2019 Bolt Innovation Management, LLC 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #ifndef ZEPHYR_INCLUDE_FS_LITTLEFS_H_ 8 #define ZEPHYR_INCLUDE_FS_LITTLEFS_H_ 9 10 #include <zephyr/types.h> 11 #include <zephyr/kernel.h> 12 #include <zephyr/storage/flash_map.h> 13 14 #include <lfs.h> 15 16 #ifdef __cplusplus 17 extern "C" { 18 #endif 19 20 /** @brief Filesystem info structure for LittleFS mount */ 21 struct fs_littlefs { 22 /* Defaulted in driver, customizable before mount. */ 23 struct lfs_config cfg; 24 25 /* Must be cfg.cache_size */ 26 uint8_t *read_buffer; 27 28 /* Must be cfg.cache_size */ 29 uint8_t *prog_buffer; 30 31 /* Must be cfg.lookahead_size/4 elements, and 32 * cfg.lookahead_size must be a multiple of 8. 33 */ 34 uint32_t *lookahead_buffer[CONFIG_FS_LITTLEFS_LOOKAHEAD_SIZE / sizeof(uint32_t)]; 35 36 /* These structures are filled automatically at mount. */ 37 struct lfs lfs; 38 void *backend; 39 struct k_mutex mutex; 40 }; 41 42 /** @brief Define a littlefs configuration with customized size 43 * characteristics. 44 * 45 * This defines static arrays required for caches, and initializes the 46 * littlefs configuration structure to use the provided values instead 47 * of the global Kconfig defaults. A pointer to the named object must 48 * be stored in the @ref fs_mount_t.fs_data field of a @ref fs_mount_t object. 49 * 50 * To define an instance for the Kconfig defaults, use 51 * @ref FS_LITTLEFS_DECLARE_DEFAULT_CONFIG. 52 * 53 * To completely control file system configuration the application can 54 * directly define and initialize a @ref fs_littlefs 55 * object. The application is responsible for ensuring the configured 56 * values are consistent with littlefs requirements. 57 * 58 * @note If you use a non-default configuration for cache size, you 59 * must also select @kconfig{CONFIG_FS_LITTLEFS_FC_HEAP_SIZE} to relax 60 * the size constraints on per-file cache allocations. 61 * 62 * @param name the name for the structure. The defined object has 63 * file scope. 64 * @param alignment needed alignment for read/prog buffer for specific device 65 * @param read_sz see @kconfig{CONFIG_FS_LITTLEFS_READ_SIZE} 66 * @param prog_sz see @kconfig{CONFIG_FS_LITTLEFS_PROG_SIZE} 67 * @param cache_sz see @kconfig{CONFIG_FS_LITTLEFS_CACHE_SIZE} 68 * @param lookahead_sz see @kconfig{CONFIG_FS_LITTLEFS_LOOKAHEAD_SIZE} 69 */ 70 #define FS_LITTLEFS_DECLARE_CUSTOM_CONFIG(name, alignment, read_sz, prog_sz, cache_sz, \ 71 lookahead_sz) \ 72 static uint8_t __aligned(alignment) name ## _read_buffer[cache_sz]; \ 73 static uint8_t __aligned(alignment) name ## _prog_buffer[cache_sz]; \ 74 static uint32_t name ## _lookahead_buffer[(lookahead_sz) / sizeof(uint32_t)]; \ 75 static struct fs_littlefs name = { \ 76 .cfg = { \ 77 .read_size = (read_sz), \ 78 .prog_size = (prog_sz), \ 79 .cache_size = (cache_sz), \ 80 .lookahead_size = (lookahead_sz), \ 81 .read_buffer = name ## _read_buffer, \ 82 .prog_buffer = name ## _prog_buffer, \ 83 .lookahead_buffer = name ## _lookahead_buffer, \ 84 }, \ 85 } 86 87 /** @brief Define a littlefs configuration with default characteristics. 88 * 89 * This defines static arrays and initializes the littlefs 90 * configuration structure to use the default size configuration 91 * provided by Kconfig. 92 * 93 * @param name the name for the structure. The defined object has 94 * file scope. 95 */ 96 #define FS_LITTLEFS_DECLARE_DEFAULT_CONFIG(name) \ 97 FS_LITTLEFS_DECLARE_CUSTOM_CONFIG(name, \ 98 4, \ 99 CONFIG_FS_LITTLEFS_READ_SIZE, \ 100 CONFIG_FS_LITTLEFS_PROG_SIZE, \ 101 CONFIG_FS_LITTLEFS_CACHE_SIZE, \ 102 CONFIG_FS_LITTLEFS_LOOKAHEAD_SIZE) 103 104 #ifdef __cplusplus 105 } 106 #endif 107 108 #endif /* ZEPHYR_INCLUDE_FS_LITTLEFS_H_ */ 109
