xiaoxiang781216 commented on code in PR #6829: URL: https://github.com/apache/incubator-nuttx/pull/6829#discussion_r957947818
########## drivers/mtd/mtd_config_fs.c: ########## @@ -0,0 +1,2652 @@ +/**************************************************************************** + * drivers/mtd/mtd_config_fs.c + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. The + * ASF licenses this file to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance with the + * License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the + * License for the specific language governing permissions and limitations + * under the License. + * + * NVS: non volatile storage in flash + * + * Copyright (c) 2018 Laczen + * + * SPDX-License-Identifier: Apache-2.0 + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> +#include <sys/types.h> +#include <stdbool.h> +#include <stdio.h> +#include <string.h> +#include <nuttx/crc8.h> +#include <debug.h> +#include <fcntl.h> +#include <errno.h> +#include <sys/poll.h> +#include <nuttx/kmalloc.h> +#include <nuttx/mtd/mtd.h> +#include <nuttx/mtd/configdata.h> + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +#define CONFIG_MTD_NVS_WRITE_BLOCK_SIZE 4 +#define NVS_WRITE_BLOCK_SIZE CONFIG_MTD_NVS_WRITE_BLOCK_SIZE +#define MIN(a, b) ((a) > (b) ? (b) : (a)) + +/* MASKS AND SHIFT FOR ADDRESSES + * an address in nvs is an uint32_t where: + * high 2 bytes represent the sector number + * low 2 bytes represent the offset in a sector + */ +#define ADDR_SECT_MASK 0xFFFF0000 +#define ADDR_SECT_SHIFT 16 +#define ADDR_OFFS_MASK 0x0000FFFF + +/* Status return values */ + +#define NVS_STATUS_NOSPACE 1 + +#define NVS_BLOCK_SIZE 32 + +#define NVS_LOOKUP_CACHE_NO_ADDR 0xFFFFFFFF + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +/** + * @brief Non-volatile Storage File system structure + * + * @param ate_wra: Allocation table entry write address. Addresses are stored + * as uint32_t: high 2 bytes are sector, low 2 bytes are offset in sector, + * @param data_wra: Data write address. + * @param sector_size File system is divided into sectors each sector + * should be multiple of pagesize + * @param sector_count Amount of sectors in the file systems + * @param write_block_size Alignment size + * @param nvs_lock Mutex + * @param flash_device Flash Device + */ + +struct nvs_fs +{ + FAR struct mtd_dev_s *mtd; /* mtd device */ + uint32_t ate_wra; /* next alloc table entry + * write address + */ + uint32_t data_wra; /* next data write address */ + uint16_t sector_size; /* filesystem is divided into + * sectors, sector size should be + * multiple of pagesize + */ + uint16_t page_size; /* page size */ + uint16_t sector_count; /* amount of sectors */ + bool ready; /* is the filesystem initialized */ + + uint32_t step_addr; /* for traverse */ + mutex_t nvs_lock; + +#ifdef CONFIG_MTD_CONFIG_FAIL_SAFE_LOOKUP_CACHE + uint32_t lookup_cache[CONFIG_MTD_CONFIG_FAIL_SAFE_LOOKUP_CACHE_SIZE]; +#endif +}; + +/* Allocation Table Entry */ + +begin_packed_struct struct nvs_ate +{ + uint32_t id; /* data id */ + uint16_t offset; /* data offset within sector */ + uint16_t len; /* data len within sector */ + uint16_t key_len; /* key string len */ + uint8_t part; /* part of a multipart data - future extension */ + uint8_t crc8; /* crc8 check of the ate entry */ + uint8_t expired; /* 0xFF-newest entry, others-old entry */ + uint8_t reserved[3]; /* for future extension */ +} end_packed_struct; + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +/* MTD NVS opeation api */ + +static int mtdnvs_open(FAR struct file *filep); +static int mtdnvs_close(FAR struct file *filep); +static ssize_t mtdnvs_read(FAR struct file *filep, FAR char *buffer, + size_t buflen); +static int mtdnvs_ioctl(FAR struct file *filep, int cmd, + unsigned long arg); +static int mtdnvs_poll(FAR struct file *filep, FAR struct pollfd *fds, + bool setup); + +/* Basic flash operation api */ + +static ssize_t flash_read(FAR struct mtd_dev_s *mtd, off_t offset, + FAR void *data, size_t len); +static ssize_t flash_write(FAR struct mtd_dev_s *mtd, off_t offset, + FAR const uint8_t *data, size_t len); +static int flash_erase(FAR struct mtd_dev_s *mtd, off_t offset, size_t len); + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +static const struct file_operations mtdnvs_fops = +{ + mtdnvs_open, /* open */ + mtdnvs_close, /* close */ + mtdnvs_read, /* read */ + NULL, /* write */ + NULL, /* seek */ + mtdnvs_ioctl, /* ioctl */ + mtdnvs_poll /* poll */ +#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS + , NULL /* unlink */ +#endif +}; + +/**************************************************************************** + * Public Data + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: fnv_hash_32 + ****************************************************************************/ + +static uint32_t fnv_hash_32(FAR const uint8_t *input, uint32_t len) +{ + uint32_t i = 0; + uint32_t hval = 2166136261; + + /* FNV-1 hash each octet in the buffer */ + + while (i++ < len) + { + /* multiply by the 32 bit FNV magic prime mod 2^32 */ + + hval *= 0x01000193; + + /* xor the bottom with the current octet */ + + hval ^= (uint32_t)*input++; + } + + return hval; +} + +#ifdef CONFIG_MTD_CONFIG_FAIL_SAFE_LOOKUP_CACHE + +/**************************************************************************** + * Name: nvs_lookup_cache_pos + ****************************************************************************/ + +static inline size_t nvs_lookup_cache_pos(uint32_t id) +{ + return id % CONFIG_MTD_CONFIG_FAIL_SAFE_LOOKUP_CACHE_SIZE; +} + +/**************************************************************************** + * Name: nvs_lookup_cache_rebuild + ****************************************************************************/ + +static int nvs_lookup_cache_rebuild(FAR struct nvs_fs *fs) +{ + int rc; + uint32_t addr; + uint32_t ate_addr; + FAR uint32_t *cache_entry; + struct nvs_ate ate; + + memset(fs->lookup_cache, CONFIG_MTD_CONFIG_ERASEDVALUE, + sizeof(fs->lookup_cache)); + addr = fs->ate_wra; + + while (true) + { + /* Make a copy of 'addr' as it will be advanced by nvs_pref_ate() */ + + ate_addr = addr; + rc = nvs_prev_ate(fs, &addr, &ate); + + if (rc) + { + return rc; + } + + cache_entry = &fs->lookup_cache[nvs_lookup_cache_pos(ate.id)]; + + if (ate.id != 0xffffffff && *cache_entry == NVS_LOOKUP_CACHE_NO_ADDR && Review Comment: If 0xffffffff is valid, why you check it here? -- This is an automated message from the Apache Git Service. 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