init.c

#define LOG_PAGE_SIZE 128
static u8_t spiffs_work_buf[LOG_PAGE_SIZE*2];
static u8_t spiffs_fds[32*4];
static u8_t spiffs_cache_buf[(LOG_PAGE_SIZE+32)*4];

void my_spiffs_mount(void) {
    spiffs_config cfg;
    cfg.phys_addr        = 0;           // start spiffs at start of spi flash
    cfg.phys_size        = flash_get_size() - cfg.phys_addr; // use all spi flash
    cfg.phys_erase_block = BLOCK_4K;    // according to datasheet
    cfg.log_block_size   = BLOCK_4K;    // let us not complicate things
    cfg.log_page_size    = LOG_PAGE_SIZE;
    cfg.hal_read_f  = (spiffs_read)  flash_read_page;
    cfg.hal_write_f = (spiffs_write) flash_write_page;
    cfg.hal_erase_f = (spiffs_erase) flash_erase_block;
    int res = SPIFFS_mount(&spi_fs,
        &cfg,
        spiffs_work_buf,
        spiffs_fds,
        sizeof(spiffs_fds),
        spiffs_cache_buf,
        sizeof(spiffs_cache_buf),
        0);

    if (res < 0) {
        DEBUG("mount failed, formatting device…\n");
        SPIFFS_format(&spi_fs);
        DEBUG("done.\n");

        my_spiffs_mount();
    }
}

spiffs_config.h

/*
 * spiffs_config.h
 *
 *  Created on: Jul 3, 2013
 *      Author: petera
 */

#ifndef SPIFFS_CONFIG_H_
#define SPIFFS_CONFIG_H_

// ----------- 8< ------------
// Following includes are for the linux test build of spiffs
// These may/should/must be removed/altered/replaced in your target
#include <stdlib.h>
#include <string.h>
#include <stddef.h>
#include "printf.h"
// ----------- >8 ------------

typedef signed int s32_t;
typedef unsigned int u32_t;
typedef signed short s16_t;
typedef unsigned short u16_t;
typedef signed char s8_t;
typedef unsigned char u8_t;

// compile time switches

// Set generic spiffs debug output call.
#ifndef SPIFFS_DGB
#define SPIFFS_DBG(...)	// printf(__VA_ARGS__)
#endif
// Set spiffs debug output call for garbage collecting.
#ifndef SPIFFS_GC_DGB
#define SPIFFS_GC_DBG(...) //printf(__VA_ARGS__)
#endif
// Set spiffs debug output call for caching.
#ifndef SPIFFS_CACHE_DGB
#define SPIFFS_CACHE_DBG(...) //printf(__VA_ARGS__)
#endif
// Set spiffs debug output call for system consistency checks.
#ifndef SPIFFS_CHECK_DGB
#define SPIFFS_CHECK_DBG(...) //printf(__VA_ARGS__)
#endif

// Enable/disable API functions to determine exact number of bytes
// for filedescriptor and cache buffers. Once decided for a configuration,
// this can be disabled to reduce flash.
#ifndef SPIFFS_BUFFER_HELP
#define SPIFFS_BUFFER_HELP              0
#endif

// Enables/disable memory read caching of nucleus file system operations.
// If enabled, memory area must be provided for cache in SPIFFS_mount.
#ifndef  SPIFFS_CACHE
#define SPIFFS_CACHE                    1
#endif
#if SPIFFS_CACHE
// Enables memory write caching for file descriptors in hydrogen
#ifndef  SPIFFS_CACHE_WR
#define SPIFFS_CACHE_WR                 1
#endif

// Enable/disable statistics on caching. Debug/test purpose only.
#ifndef  SPIFFS_CACHE_STATS
#define SPIFFS_CACHE_STATS              1
#endif
#endif

// Always check header of each accessed page to ensure consistent state.
// If enabled it will increase number of reads, will increase flash.
#ifndef SPIFFS_PAGE_CHECK
#define SPIFFS_PAGE_CHECK               1
#endif

// Define maximum number of gc runs to perform to reach desired free pages.
#ifndef SPIFFS_GC_MAX_RUNS
#define SPIFFS_GC_MAX_RUNS              5
#endif

// Enable/disable statistics on gc. Debug/test purpose only.
#ifndef SPIFFS_GC_STATS
#define SPIFFS_GC_STATS                 0
#endif

// Garbage collecting examines all pages in a block which and sums up
// to a block score. Deleted pages normally gives positive score and
// used pages normally gives a negative score (as these must be moved).
// To have a fair wear-leveling, the erase age is also included in score,
// whose factor normally is the most positive.
// The larger the score, the more likely it is that the block will
// picked for garbage collection.

// Garbage collecting heuristics - weight used for deleted pages.
#ifndef SPIFFS_GC_HEUR_W_DELET
#define SPIFFS_GC_HEUR_W_DELET          (5)
#endif
// Garbage collecting heuristics - weight used for used pages.
#ifndef SPIFFS_GC_HEUR_W_USED
#define SPIFFS_GC_HEUR_W_USED           (-1)
#endif
// Garbage collecting heuristics - weight used for time between
// last erased and erase of this block.
#ifndef SPIFFS_GC_HEUR_W_ERASE_AGE
#define SPIFFS_GC_HEUR_W_ERASE_AGE      (50)
#endif

// Object name maximum length.
#ifndef SPIFFS_OBJ_NAME_LEN
#define SPIFFS_OBJ_NAME_LEN             (32)
#endif

// Size of buffer allocated on stack used when copying data.
// Lower value generates more read/writes. No meaning having it bigger
// than logical page size.
#ifndef SPIFFS_COPY_BUFFER_STACK
#define SPIFFS_COPY_BUFFER_STACK        (64)
#endif

// Enable this to have an identifiable spiffs filesystem. This will look for
// a magic in all sectors to determine if this is a valid spiffs system or
// not on mount point. If not, SPIFFS_format must be called prior to mounting
// again.
#ifndef SPIFFS_USE_MAGIC
#define SPIFFS_USE_MAGIC                (1)
#endif

// SPIFFS_LOCK and SPIFFS_UNLOCK protects spiffs from reentrancy on api level
// These should be defined on a multithreaded system

// define this to enter a mutex if you're running on a multithreaded system
#ifndef SPIFFS_LOCK
#define SPIFFS_LOCK(fs)
#endif
// define this to exit a mutex if you're running on a multithreaded system
#ifndef SPIFFS_UNLOCK
#define SPIFFS_UNLOCK(fs)
#endif


// Enable if only one spiffs instance with constant configuration will exist
// on the target. This will reduce calculations, flash and memory accesses.
// Parts of configuration must be defined below instead of at time of mount.
#ifndef SPIFFS_SINGLETON
#define SPIFFS_SINGLETON 0
#endif

#if SPIFFS_SINGLETON
// Instead of giving parameters in config struct, singleton build must
// give parameters in defines below.
#ifndef SPIFFS_CFG_PHYS_SZ
#define SPIFFS_CFG_PHYS_SZ(ignore)        (1024*1024*2)
#endif
#ifndef SPIFFS_CFG_PHYS_ERASE_SZ
#define SPIFFS_CFG_PHYS_ERASE_SZ(ignore)  (65536)
#endif
#ifndef SPIFFS_CFG_PHYS_ADDR
#define SPIFFS_CFG_PHYS_ADDR(ignore)      (0)
#endif
#ifndef SPIFFS_CFG_LOG_PAGE_SZ
#define SPIFFS_CFG_LOG_PAGE_SZ(ignore)    (256)
#endif
#ifndef SPIFFS_CFG_LOG_BLOCK_SZ
#define SPIFFS_CFG_LOG_BLOCK_SZ(ignore)   (65536)
#endif
#endif

// Enable this if your target needs aligned data for index tables
#ifndef SPIFFS_ALIGNED_OBJECT_INDEX_TABLES
#define SPIFFS_ALIGNED_OBJECT_INDEX_TABLES       0
#endif

// Set SPIFFS_TEST_VISUALISATION to non-zero to enable SPIFFS_vis function
// in the api. This function will visualize all filesystem using given printf
// function.
#ifndef SPIFFS_TEST_VISUALISATION
#define SPIFFS_TEST_VISUALISATION         0
#endif
#if SPIFFS_TEST_VISUALISATION
#ifndef spiffs_printf
#define spiffs_printf(...)                printf(__VA_ARGS__)
#endif
// spiffs_printf argument for a free page
#ifndef SPIFFS_TEST_VIS_FREE_STR
#define SPIFFS_TEST_VIS_FREE_STR          "_"
#endif
// spiffs_printf argument for a deleted page
#ifndef SPIFFS_TEST_VIS_DELE_STR
#define SPIFFS_TEST_VIS_DELE_STR          "/"
#endif
// spiffs_printf argument for an index page for given object id
#ifndef SPIFFS_TEST_VIS_INDX_STR
#define SPIFFS_TEST_VIS_INDX_STR(id)      "i"
#endif
// spiffs_printf argument for a data page for given object id
#ifndef SPIFFS_TEST_VIS_DATA_STR
#define SPIFFS_TEST_VIS_DATA_STR(id)      "d"
#endif
#endif

// Types depending on configuration such as the amount of flash bytes
// given to spiffs file system in total (spiffs_file_system_size),
// the logical block size (log_block_size), and the logical page size
// (log_page_size)

// Block index type. Make sure the size of this type can hold
// the highest number of all blocks - i.e. spiffs_file_system_size / log_block_size
typedef u16_t spiffs_block_ix;
// Page index type. Make sure the size of this type can hold
// the highest page number of all pages - i.e. spiffs_file_system_size / log_page_size
typedef u16_t spiffs_page_ix;
// Object id type - most significant bit is reserved for index flag. Make sure the
// size of this type can hold the highest object id on a full system,
// i.e. 2 + (spiffs_file_system_size / (2*log_page_size))*2
typedef u16_t spiffs_obj_id;
// Object span index type. Make sure the size of this type can
// hold the largest possible span index on the system -
// i.e. (spiffs_file_system_size / log_page_size) - 1
typedef u16_t spiffs_span_ix;

#endif /* SPIFFS_CONFIG_H_ */