/**************************************************************************** * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* MASKS AND SHIFT FOR ADDRESSES * an address in nvs is an uint32_t where: * high 2 bytes represent the block number * low 2 bytes represent the offset in a block */ #define ADDR_BLOCK_MASK 0xFFFF0000 #define ADDR_BLOCK_SHIFT 16 #define ADDR_OFFS_MASK 0x0000FFFF /* We don't want to store all the read content in stack or heap, * so we make a buffer to do compare or move. */ #define NVS_BUFFER_SIZE MAX(NVS_ALIGN_UP(32), NVS_ALIGN_SIZE) /* If data is written after last ate, and power loss happens, * we need to find a clean offset by skipping dirty data. * This macro defines how many bytes to skip when dirty data * is spotted(may take several skips). * Normally 1 byte is okay, such process only happens when * nvs is started, and it is acceptable to take some time during * starting. */ #define NVS_CORRUPT_DATA_SKIP_STEP NVS_ALIGN_SIZE /* Gc done or close ate has the id of 0xffffffff. * We can tell if the ate is special by looking at its id. */ #define NVS_SPECIAL_ATE_ID 0xffffffff #define NVS_ALIGN_SIZE CONFIG_MTD_WRITE_ALIGN_SIZE #define NVS_ALIGN_UP(x) (((x) + NVS_ALIGN_SIZE - 1) & ~(NVS_ALIGN_SIZE - 1)) /**************************************************************************** * Private Types ****************************************************************************/ /* Non-volatile Storage File system structure */ struct nvs_fs { FAR struct mtd_dev_s *mtd; /* MTD device */ uint32_t blocksize; /* Size of one nvs block */ uint32_t nblocks; /* Number of nvs blocks */ uint8_t erasestate; /* Erased value */ uint32_t ate_wra; /* Next alloc table entry * Write address */ uint32_t data_wra; /* Next data write address */ uint32_t step_addr; /* For traverse */ mutex_t nvs_lock; }; /* Allocation Table Entry */ begin_packed_struct struct nvs_ate { uint32_t id; /* Data id */ uint16_t offset; /* Data offset within block */ uint16_t len; /* Data len within block */ 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 */ #if CONFIG_MTD_WRITE_ALIGN_SIZE <= 4 /* stay compatible with situation which align byte be 1 */ uint8_t expired[NVS_ALIGN_SIZE]; uint8_t reserved[4 - NVS_ALIGN_SIZE]; #else uint8_t padding[NVS_ALIGN_UP(12) - 12]; uint8_t expired[NVS_ALIGN_SIZE]; #endif } end_packed_struct; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* MTD NVS opeation api */ static int mtdconfig_open(FAR struct file *filep); static int mtdconfig_close(FAR struct file *filep); static ssize_t mtdconfig_read(FAR struct file *filep, FAR char *buffer, size_t buflen); static int mtdconfig_ioctl(FAR struct file *filep, int cmd, unsigned long arg); static int mtdconfig_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup); /**************************************************************************** * Private Data ****************************************************************************/ static const struct file_operations g_mtdnvs_fops = { mtdconfig_open, /* Open */ mtdconfig_close, /* Close */ mtdconfig_read, /* Read */ NULL, /* Write */ NULL, /* Seek */ mtdconfig_ioctl, /* Ioctl */ NULL, /* Truncate */ NULL, /* Mmap */ mtdconfig_poll /* Poll */ }; /**************************************************************************** * Public Data ****************************************************************************/ /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: nvs_fnv_hash ****************************************************************************/ static uint32_t nvs_fnv_hash(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 ^= *input++; } return hval; } /**************************************************************************** * Name: nvs_flash_wrt * * Description: * Flash routines, process offset then write. * ****************************************************************************/ static int nvs_flash_wrt(FAR struct nvs_fs *fs, uint32_t addr, FAR const void *data, size_t len) { off_t offset; int ret; offset = fs->blocksize * (addr >> ADDR_BLOCK_SHIFT); offset += addr & ADDR_OFFS_MASK; ret = MTD_WRITE(fs->mtd, offset, len, data); if (ret < 0) { return ret; } return OK; } /**************************************************************************** * Name: nvs_flash_rd * * Description: * Basic flash read from nvs address. * ****************************************************************************/ static int nvs_flash_rd(FAR struct nvs_fs *fs, uint32_t addr, FAR void *data, size_t len) { off_t offset; int ret; offset = fs->blocksize * (addr >> ADDR_BLOCK_SHIFT); offset += addr & ADDR_OFFS_MASK; ret = MTD_READ(fs->mtd, offset, len, data); if (ret < 0) { return ret; } return OK; } /**************************************************************************** * Name: nvs_flash_ate_wrt * * Description: * Allocation entry write. * ****************************************************************************/ static int nvs_flash_ate_wrt(FAR struct nvs_fs *fs, FAR const struct nvs_ate *entry) { int rc; rc = nvs_flash_wrt(fs, fs->ate_wra, entry, sizeof(struct nvs_ate)); fs->ate_wra -= sizeof(struct nvs_ate); return rc; } /**************************************************************************** * Name: nvs_flash_data_wrt ****************************************************************************/ static int nvs_flash_data_wrt(FAR struct nvs_fs *fs, FAR const void *data, size_t len) { int rc; rc = nvs_flash_wrt(fs, fs->data_wra, data, len); fs->data_wra += len; finfo("write data done, data_wra=0x%" PRIx32 "\n", fs->data_wra); return rc; } /**************************************************************************** * Name: nvs_flash_ate_rd ****************************************************************************/ static int nvs_flash_ate_rd(FAR struct nvs_fs *fs, uint32_t addr, FAR struct nvs_ate *entry) { return nvs_flash_rd(fs, addr, entry, sizeof(struct nvs_ate)); } /**************************************************************************** * Name: nvs_flash_block_cmp * * Description: * Compares the data in flash at addr to data * in blocks of size NVS_BLOCK_SIZE aligned to fs->write_block_size. * Returns 0 if equal, 1 if not equal, errcode if error. * ****************************************************************************/ static int nvs_flash_block_cmp(FAR struct nvs_fs *fs, uint32_t addr, FAR const void *data, size_t len) { FAR const uint8_t *data8 = (FAR const uint8_t *)data; int rc; size_t bytes_to_cmp; uint8_t buf[NVS_BUFFER_SIZE]; while (len > 0) { bytes_to_cmp = MIN(NVS_BUFFER_SIZE, len); rc = nvs_flash_rd(fs, addr, buf, bytes_to_cmp); if (rc) { return rc; } rc = memcmp(data8, buf, bytes_to_cmp); if (rc) { return 1; } len -= bytes_to_cmp; addr += bytes_to_cmp; data8 += bytes_to_cmp; } return 0; } /**************************************************************************** * Name: nvs_flash_direct_cmp * * Description: * Compares the data in flash at addr1 and addr2 * of len in blocks of size NVS_BLOCK_SIZE aligned to fs->write_block_size. * Returns 0 if equal, 1 if not equal, errcode if error. * ****************************************************************************/ static int nvs_flash_direct_cmp(FAR struct nvs_fs *fs, uint32_t addr1, uint32_t addr2, size_t len) { int rc; size_t bytes_to_cmp; uint8_t buf1[NVS_BUFFER_SIZE]; uint8_t buf2[NVS_BUFFER_SIZE]; while (len > 0) { bytes_to_cmp = MIN(NVS_BUFFER_SIZE, len); rc = nvs_flash_rd(fs, addr1, buf1, bytes_to_cmp); if (rc) { return rc; } rc = nvs_flash_rd(fs, addr2, buf2, bytes_to_cmp); if (rc) { return rc; } rc = memcmp(buf1, buf2, bytes_to_cmp); if (rc) { return 1; } len -= bytes_to_cmp; addr1 += bytes_to_cmp; addr2 += bytes_to_cmp; } return 0; } /**************************************************************************** * Name: nvs_flash_cmp_const * * Description: * Compares the data in flash at addr to a constant * value. returns 0 if all data in flash is equal to value, 1 if not equal, * errcode if error. * ****************************************************************************/ static int nvs_flash_cmp_const(FAR struct nvs_fs *fs, uint32_t addr, uint8_t value, size_t len) { int rc; size_t bytes_to_cmp; uint8_t cmp[NVS_BUFFER_SIZE]; memset(cmp, value, NVS_BUFFER_SIZE); while (len > 0) { bytes_to_cmp = MIN(NVS_BUFFER_SIZE, len); rc = nvs_flash_block_cmp(fs, addr, cmp, bytes_to_cmp); if (rc) { return rc; } len -= bytes_to_cmp; addr += bytes_to_cmp; } return 0; } /**************************************************************************** * Name: nvs_flash_block_move * * Description: * Move a block at addr to the current data write * location and updates the data write location. * ****************************************************************************/ static int nvs_flash_block_move(FAR struct nvs_fs *fs, uint32_t addr, size_t len) { int rc; size_t bytes_to_copy; uint8_t buf[NVS_BUFFER_SIZE]; while (len) { bytes_to_copy = MIN(NVS_BUFFER_SIZE, len); rc = nvs_flash_rd(fs, addr, buf, bytes_to_copy); if (rc) { return rc; } rc = nvs_flash_data_wrt(fs, buf, bytes_to_copy); if (rc) { return rc; } len -= bytes_to_copy; addr += bytes_to_copy; } return 0; } /**************************************************************************** * Name: nvs_flash_erase_block * * Description: * Erase a block by first checking it is used and then erasing if required. * Return 0 if OK, errorcode on error. * ****************************************************************************/ static int nvs_flash_erase_block(FAR struct nvs_fs *fs, uint32_t addr) { int rc; finfo("Erasing addr %" PRIx32 "\n", addr); rc = MTD_ERASE(fs->mtd, CONFIG_MTD_BLOCKSIZE_MULTIPLE * (addr >> ADDR_BLOCK_SHIFT), CONFIG_MTD_BLOCKSIZE_MULTIPLE); if (rc < 0) { ferr("Erasing failed %d\n", rc); return rc; } return 0; } /**************************************************************************** * Name: nvs_ate_crc8_update * * Description: * Crc update on allocation entry. * ****************************************************************************/ static void nvs_ate_crc8_update(FAR struct nvs_ate *entry) { uint8_t ate_crc; ate_crc = crc8part((FAR const uint8_t *)entry, offsetof(struct nvs_ate, crc8), 0xff); entry->crc8 = ate_crc; } /**************************************************************************** * Name: nvs_ate_crc8_check * * Description: * Crc check on allocation entry. * Returns 0 if OK, 1 on crc fail. * ****************************************************************************/ static int nvs_ate_crc8_check(FAR const struct nvs_ate *entry) { uint8_t ate_crc; ate_crc = crc8part((FAR const uint8_t *)entry, offsetof(struct nvs_ate, crc8), 0xff); if (ate_crc == entry->crc8) { return 0; } return 1; } /**************************************************************************** * Name: nvs_ate_cmp_const * * Description: * Compares an ATE to a constant value. returns 0 if * the whole ATE is equal to value, 1 if not equal. * ****************************************************************************/ static int nvs_ate_cmp_const(FAR const struct nvs_ate *entry, uint8_t value) { FAR const uint8_t *data8 = (FAR const uint8_t *)entry; int i; for (i = 0; i < sizeof(struct nvs_ate); i++) { if (data8[i] != value) { return 1; } } return 0; } /**************************************************************************** * Name: nvs_ate_valid * * Description: * Return 1 if crc8 and offset valid, 0 otherwise * ****************************************************************************/ static int nvs_ate_valid(FAR struct nvs_fs *fs, FAR const struct nvs_ate *entry) { if (nvs_ate_crc8_check(entry) || entry->offset >= (fs->blocksize - sizeof(struct nvs_ate))) { return 0; } return 1; } /**************************************************************************** * Name: nvs_close_ate_valid * * Description: * Validates an block close ate: * A valid block close ate: * - Calid ate. * - Len = 0 and id = 0xFFFFFFFF. * - Offset points to location at ate multiple from block size. * Return 1 if valid, 0 otherwise. * ****************************************************************************/ static int nvs_close_ate_valid(FAR struct nvs_fs *fs, FAR const struct nvs_ate *entry) { if (!nvs_ate_valid(fs, entry) || entry->len != 0 || entry->id != NVS_SPECIAL_ATE_ID) { return 0; } if ((fs->blocksize - entry->offset) % sizeof(struct nvs_ate)) { return 0; } return 1; } /**************************************************************************** * Name: nvs_flash_write_multi_blk * * Description: * Store multi align block in flash * * Returned Value: * number of bytes at the end of addr which is left to write next time. * zero indicates all bytes were written . On error returns -ERRNO code. ****************************************************************************/ int nvs_flash_write_multi_blk(FAR struct nvs_fs *fs, const uint8_t *addr, size_t size) { size_t blk_cnt; int left; int rc; blk_cnt = size / NVS_ALIGN_SIZE; left = size % NVS_ALIGN_SIZE; if (blk_cnt) { rc = nvs_flash_data_wrt(fs, addr, size - left); if (rc) { ferr("Write multi data value failed, rc=%d\n", rc); return rc; } } return left; } /**************************************************************************** * Name: nvs_flash_wrt_entry * * Description: * Store an entry in flash * ****************************************************************************/ static int nvs_flash_wrt_entry(FAR struct nvs_fs *fs, uint32_t id, FAR const uint8_t *key, size_t key_size, FAR const void *data, size_t len) { int rc; struct nvs_ate entry; uint16_t left; uint16_t copy_len = 0; uint8_t buf[NVS_ALIGN_SIZE]; memset(&entry, fs->erasestate, sizeof(entry)); entry.id = id; entry.offset = fs->data_wra & ADDR_OFFS_MASK; entry.len = len; entry.key_len = key_size; nvs_ate_crc8_update(&entry); /* Let's save key and data into one, key comes first, then data */ rc = nvs_flash_write_multi_blk(fs, key, key_size); if (rc < 0) { return rc; } if (rc) { /* Write align block which inlcude part key + part data */ left = rc; memset(buf, fs->erasestate, NVS_ALIGN_SIZE); copy_len = (left + len) <= NVS_ALIGN_SIZE ? len : (NVS_ALIGN_SIZE - left); memcpy(buf, key + key_size - left, left); memcpy(buf + left, data, copy_len); rc = nvs_flash_data_wrt(fs, buf, NVS_ALIGN_SIZE); if (rc) { ferr("Write value failed, rc=%d\n", rc); return rc; } } rc = nvs_flash_write_multi_blk(fs, data + copy_len, len - copy_len); if (rc < 0) { return rc; } if (rc) { /* Add padding at the end of data */ left = rc; memset(buf, fs->erasestate, NVS_ALIGN_SIZE); memcpy(buf, data + len - left, left); rc = nvs_flash_data_wrt(fs, buf, NVS_ALIGN_SIZE); if (rc) { ferr("Write value failed, rc=%d\n", rc); return rc; } } /* Last, let's save entry to flash */ rc = nvs_flash_ate_wrt(fs, &entry); if (rc) { ferr("Write ate failed, rc=%d\n", rc); return rc; } return 0; } /**************************************************************************** * Name: nvs_recover_last_ate * * Description: * If the closing ate is invalid, its offset cannot be trusted and * the last valid ate of the block should instead try to be recovered * by going through all ate's. * * Addr should point to the faulty closing ate and will be updated to * the last valid ate. If no valid ate is found it will be left untouched. * ****************************************************************************/ static int nvs_recover_last_ate(FAR struct nvs_fs *fs, FAR uint32_t *addr) { uint32_t data_end_addr; uint32_t ate_end_addr; struct nvs_ate end_ate; int rc; finfo("Recovering last ate from block %" PRIu32 "\n", (*addr >> ADDR_BLOCK_SHIFT)); *addr -= sizeof(struct nvs_ate); ate_end_addr = *addr; data_end_addr = *addr & ADDR_BLOCK_MASK; while (ate_end_addr > data_end_addr) { rc = nvs_flash_ate_rd(fs, ate_end_addr, &end_ate); if (rc) { return rc; } if (nvs_ate_valid(fs, &end_ate)) { /* Found a valid ate, update data_end_addr and *addr */ data_end_addr &= ADDR_BLOCK_MASK; data_end_addr += end_ate.offset + NVS_ALIGN_UP(end_ate.key_len + end_ate.len); *addr = ate_end_addr; } if (ate_end_addr < sizeof(struct nvs_ate)) { break; } ate_end_addr -= sizeof(struct nvs_ate); } return 0; } /**************************************************************************** * Name: nvs_prev_ate * * Description: * Walking through allocation entry list, from newest to oldest entries. * Read ate from addr, modify addr to the previous ate. * ****************************************************************************/ static int nvs_prev_ate(FAR struct nvs_fs *fs, FAR uint32_t *addr, FAR struct nvs_ate *ate) { int rc; struct nvs_ate close_ate; rc = nvs_flash_ate_rd(fs, *addr, ate); if (rc) { return rc; } *addr += sizeof(struct nvs_ate); if (((*addr) & ADDR_OFFS_MASK) != (fs->blocksize - sizeof(struct nvs_ate))) { return 0; } /* Last ate in block, do jump to previous block */ if (((*addr) >> ADDR_BLOCK_SHIFT) == 0) { *addr += ((fs->nblocks - 1) << ADDR_BLOCK_SHIFT); } else { *addr -= (1 << ADDR_BLOCK_SHIFT); } rc = nvs_flash_ate_rd(fs, *addr, &close_ate); if (rc) { return rc; } rc = nvs_ate_cmp_const(&close_ate, fs->erasestate); /* At the end of filesystem */ if (!rc) { *addr = fs->ate_wra; return 0; } /* Update the address if the close ate is valid. */ if (nvs_close_ate_valid(fs, &close_ate)) { *addr &= ADDR_BLOCK_MASK; *addr += close_ate.offset; return 0; } /* The close_ate was invalid, `lets find out the last valid ate * and point the address to this found ate. * * Remark: if there was absolutely no valid data in the block *addr * is kept at block_end - 2*ate_size, the next read will contain * invalid data and continue with a block jump */ return nvs_recover_last_ate(fs, addr); } /**************************************************************************** * Name: nvs_block_advance ****************************************************************************/ static void nvs_block_advance(FAR struct nvs_fs *fs, FAR uint32_t *addr) { *addr += (1 << ADDR_BLOCK_SHIFT); if ((*addr >> ADDR_BLOCK_SHIFT) == fs->nblocks) { *addr -= (fs->nblocks << ADDR_BLOCK_SHIFT); } } /**************************************************************************** * Name: nvs_block_close * * Description: * Allocation entry close (this closes the current block) by writing * offset of last ate to the block end. * ****************************************************************************/ static int nvs_block_close(FAR struct nvs_fs *fs) { int rc; struct nvs_ate close_ate; memset(&close_ate, fs->erasestate, sizeof(close_ate)); close_ate.id = NVS_SPECIAL_ATE_ID; close_ate.len = 0; close_ate.key_len = 0; close_ate.offset = (fs->ate_wra + sizeof(struct nvs_ate)) & ADDR_OFFS_MASK; fs->ate_wra &= ADDR_BLOCK_MASK; fs->ate_wra += fs->blocksize - sizeof(struct nvs_ate); nvs_ate_crc8_update(&close_ate); rc = nvs_flash_ate_wrt(fs, &close_ate); if (rc < 0) { ferr("Write ate failed, rc=%d\n", rc); } nvs_block_advance(fs, &fs->ate_wra); fs->data_wra = fs->ate_wra & ADDR_BLOCK_MASK; finfo("block close, data_wra=0x%" PRIx32 "\n", fs->data_wra); return 0; } /**************************************************************************** * Name: nvs_add_gc_done_ate ****************************************************************************/ static int nvs_add_gc_done_ate(FAR struct nvs_fs *fs) { struct nvs_ate gc_done_ate; finfo("Adding gc done ate at %" PRIx32 "\n", fs->ate_wra & ADDR_OFFS_MASK); memset(&gc_done_ate, fs->erasestate, sizeof(gc_done_ate)); gc_done_ate.id = NVS_SPECIAL_ATE_ID; gc_done_ate.len = 0; gc_done_ate.key_len = 0; gc_done_ate.offset = fs->data_wra & ADDR_OFFS_MASK; nvs_ate_crc8_update(&gc_done_ate); return nvs_flash_ate_wrt(fs, &gc_done_ate); } /**************************************************************************** * Name: nvs_expire_ate ****************************************************************************/ static int nvs_expire_ate(FAR struct nvs_fs *fs, uint32_t addr) { uint8_t expired[NVS_ALIGN_SIZE]; memset(expired, ~fs->erasestate, sizeof(expired)); return nvs_flash_wrt(fs, addr + offsetof(struct nvs_ate, expired), expired, sizeof(expired)); } /**************************************************************************** * Name: nvs_gc * * Description: * Garbage collection: the address ate_wra has been updated to the new * block that has just been started. The data to gc is in the block * after this new block. * ****************************************************************************/ static int nvs_gc(FAR struct nvs_fs *fs) { int rc; struct nvs_ate close_ate; struct nvs_ate gc_ate; uint32_t sec_addr; uint32_t gc_addr; uint32_t gc_prev_addr; uint32_t data_addr; uint32_t stop_addr; finfo("gc: before gc, ate_wra %" PRIx32 "\n", fs->ate_wra); sec_addr = (fs->ate_wra & ADDR_BLOCK_MASK); nvs_block_advance(fs, &sec_addr); gc_addr = sec_addr + fs->blocksize - sizeof(struct nvs_ate); finfo("gc: set, sec_addr %" PRIx32 ", gc_addr %" PRIx32 "\n", sec_addr, gc_addr); /* If the block is not closed don't do gc */ rc = nvs_flash_ate_rd(fs, gc_addr, &close_ate); if (rc < 0) { /* Flash error */ return rc; } rc = nvs_ate_cmp_const(&close_ate, fs->erasestate); if (!rc) { goto gc_done; } stop_addr = gc_addr - sizeof(struct nvs_ate); if (nvs_close_ate_valid(fs, &close_ate)) { gc_addr &= ADDR_BLOCK_MASK; gc_addr += close_ate.offset; } else { rc = nvs_recover_last_ate(fs, &gc_addr); if (rc) { return rc; } } do { gc_prev_addr = gc_addr; rc = nvs_prev_ate(fs, &gc_addr, &gc_ate); if (rc) { return rc; } if (gc_ate.expired[0] != fs->erasestate) { /* Deleted or old ate, ignore it */ continue; } if (!nvs_ate_valid(fs, &gc_ate)) { continue; } if (gc_ate.id != NVS_SPECIAL_ATE_ID) { /* Copy needed */ finfo("Moving %" PRIu32 ", key_len %" PRIu16 ", len %" PRIu16 "\n", gc_ate.id, gc_ate.key_len, gc_ate.len); data_addr = gc_prev_addr & ADDR_BLOCK_MASK; data_addr += gc_ate.offset; gc_ate.offset = fs->data_wra & ADDR_OFFS_MASK; nvs_ate_crc8_update(&gc_ate); rc = nvs_flash_block_move(fs, data_addr, NVS_ALIGN_UP(gc_ate.key_len + gc_ate.len)); if (rc) { return rc; } rc = nvs_flash_ate_wrt(fs, &gc_ate); if (rc) { return rc; } } } while (gc_prev_addr != stop_addr); gc_done: rc = nvs_add_gc_done_ate(fs); if (rc) { return rc; } /* Erase the gc'ed block */ rc = nvs_flash_erase_block(fs, sec_addr); if (rc) { return rc; } return 0; } /**************************************************************************** * Name: nvs_startup ****************************************************************************/ static int nvs_startup(FAR struct nvs_fs *fs) { int rc; struct nvs_ate last_ate; size_t empty_len; uint32_t wlk_addr; uint32_t second_addr; uint32_t last_addr; struct nvs_ate second_ate; struct mtd_geometry_s geo; /* Initialize addr to 0 for the case fs->nblocks == 0. This * should never happen but both * Coverity and GCC believe the contrary. */ uint32_t addr = 0; uint16_t i; uint16_t closed_blocks = 0; fs->ate_wra = 0; fs->data_wra = 0; /* Get the device geometry. (Casting to uintptr_t first eliminates * complaints on some architectures where the sizeof long is different * from the size of a pointer). */ rc = MTD_IOCTL(fs->mtd, MTDIOC_GEOMETRY, (unsigned long)((uintptr_t)&(geo))); if (rc < 0) { ferr("ERROR: MTD ioctl(MTDIOC_GEOMETRY) failed: %d\n", rc); return rc; } rc = MTD_IOCTL(fs->mtd, MTDIOC_ERASESTATE, (unsigned long)((uintptr_t)&fs->erasestate)); if (rc < 0) { ferr("ERROR: MTD ioctl(MTDIOC_ERASESTATE) failed: %d\n", rc); return rc; } fs->blocksize = CONFIG_MTD_BLOCKSIZE_MULTIPLE * geo.erasesize; fs->nblocks = geo.neraseblocks / CONFIG_MTD_BLOCKSIZE_MULTIPLE; /* Check the number of blocks, it should be at least 2. */ if (fs->nblocks < 2) { ferr("Configuration error - block count\n"); return -EINVAL; } /* Step through the blocks to find a open block following * a closed block, this is where NVS can write. */ for (i = 0; i < fs->nblocks; i++) { addr = (i << ADDR_BLOCK_SHIFT) + (uint16_t)(fs->blocksize - sizeof(struct nvs_ate)); rc = nvs_flash_cmp_const(fs, addr, fs->erasestate, sizeof(struct nvs_ate)); fwarn("rc=%d\n", rc); if (rc) { /* Closed block */ closed_blocks++; nvs_block_advance(fs, &addr); rc = nvs_flash_cmp_const(fs, addr, fs->erasestate, sizeof(struct nvs_ate)); if (!rc) { /* Open block */ break; } } fwarn("i=%" PRIu16 ", closed_blocks=%" PRIu16 ", addr=0x%" PRIx32 "\n", i, closed_blocks, addr); } /* All blocks are closed, this is not a nvs fs */ if (closed_blocks == fs->nblocks) { return -EDEADLK; } if (i == fs->nblocks) { /* None of the blocks where closed, in most cases we can set * the address to the first block, except when there are only * two blocks. Then we can only set it to the first block if * the last block contains no ate's. So we check this first */ rc = nvs_flash_cmp_const(fs, addr - sizeof(struct nvs_ate), fs->erasestate, sizeof(struct nvs_ate)); if (!rc) { /* Empty ate */ nvs_block_advance(fs, &addr); } } /* Addr contains address of closing ate in the most recent block, * search for the last valid ate using the recover_last_ate routine */ rc = nvs_recover_last_ate(fs, &addr); if (rc) { return rc; } /* Addr contains address of the last valid ate in the most recent block * search for the first ate containing all cells erased, in the process * also update fs->data_wra. */ fs->ate_wra = addr; fs->data_wra = addr & ADDR_BLOCK_MASK; finfo("recovered ate ate_wra=0x%" PRIx32 ", data_wra=0x%" PRIx32 "\n", fs->ate_wra, fs->data_wra); while (fs->ate_wra >= fs->data_wra) { rc = nvs_flash_ate_rd(fs, fs->ate_wra, &last_ate); if (rc) { return rc; } rc = nvs_ate_cmp_const(&last_ate, fs->erasestate); if (!rc) { /* Found 0xff empty location */ break; } if (nvs_ate_valid(fs, &last_ate)) { /* Complete write of ate was performed */ fs->data_wra = addr & ADDR_BLOCK_MASK; fs->data_wra += last_ate.offset + NVS_ALIGN_UP(last_ate.key_len + last_ate.len); finfo("recovered data_wra=0x%" PRIx32 "\n", fs->data_wra); } fs->ate_wra -= sizeof(struct nvs_ate); } /* If the block after the write block is not empty, gc was interrupted * we might need to restart gc if it has not yet finished. Otherwise * just erase the block. * When gc needs to be restarted, first erase the block otherwise the * data might not fit into the block. */ addr = fs->ate_wra & ADDR_BLOCK_MASK; nvs_block_advance(fs, &addr); rc = nvs_flash_cmp_const(fs, addr, fs->erasestate, fs->blocksize); if (rc < 0) { return rc; } if (rc) { /* The block after fs->ate_wrt is not empty, look for a marker * (gc_done_ate) that indicates that gc was finished. */ bool gc_done_marker = false; struct nvs_ate gc_done_ate; addr = fs->ate_wra + sizeof(struct nvs_ate); while ((addr & ADDR_OFFS_MASK) < (fs->blocksize - sizeof(struct nvs_ate))) { rc = nvs_flash_ate_rd(fs, addr, &gc_done_ate); if (rc) { return rc; } if (nvs_ate_valid(fs, &gc_done_ate) && (gc_done_ate.id == NVS_SPECIAL_ATE_ID) && (gc_done_ate.len == 0)) { gc_done_marker = true; break; } addr += sizeof(struct nvs_ate); } if (gc_done_marker) { /* Erase the next block */ fwarn("GC Done marker found\n"); addr = fs->ate_wra & ADDR_BLOCK_MASK; nvs_block_advance(fs, &addr); rc = nvs_flash_erase_block(fs, addr); goto end; } fwarn("No GC Done marker found: restarting gc\n"); rc = nvs_flash_erase_block(fs, fs->ate_wra); if (rc) { return rc; } fs->ate_wra &= ADDR_BLOCK_MASK; fs->ate_wra += (fs->blocksize - 2 * sizeof(struct nvs_ate)); fs->data_wra = (fs->ate_wra & ADDR_BLOCK_MASK); finfo("GC when data_wra=0x%" PRIx32 "\n", fs->data_wra); rc = nvs_gc(fs); goto end; } /* Possible data write after last ate write, update data_wra */ while (fs->ate_wra > fs->data_wra) { empty_len = fs->ate_wra - fs->data_wra; rc = nvs_flash_cmp_const(fs, fs->data_wra, fs->erasestate, empty_len); if (rc < 0) { return rc; } if (!rc) { break; } fs->data_wra += NVS_CORRUPT_DATA_SKIP_STEP; finfo("update for powerloss data write, data_wra=0x%" PRIx32 "\n", fs->data_wra); } /* If the ate_wra is pointing to the first ate write location in a * block and data_wra is not 0, erase the block as it contains no * valid data (this also avoids closing a block without any data). */ if (((fs->ate_wra + 2 * sizeof(struct nvs_ate)) == fs->blocksize) && (fs->data_wra != (fs->ate_wra & ADDR_BLOCK_MASK))) { rc = nvs_flash_erase_block(fs, fs->ate_wra); if (rc) { return rc; } fs->data_wra = fs->ate_wra & ADDR_BLOCK_MASK; finfo("erase due to no data, data_wra=0x%" PRIx32 "\n", fs->data_wra); } /* Check if there exists an old entry with the same id and key * as the newest entry. * If so, power loss occured before writing the old entry id as expired. * We need to set old entry expired. */ wlk_addr = fs->ate_wra; while (1) { last_addr = wlk_addr; rc = nvs_prev_ate(fs, &wlk_addr, &last_ate); if (rc) { return rc; } /* Skip last one */ if (wlk_addr == fs->ate_wra) { break; } if (nvs_ate_valid(fs, &last_ate) && (last_ate.id != NVS_SPECIAL_ATE_ID)) { finfo("ate found at 0x%" PRIx32 ", id %" PRIu32 ", " "key_len %" PRIu16 ", offset %" PRIu16 "\n", last_addr, last_ate.id, last_ate.key_len, last_ate.offset); while (1) { second_addr = wlk_addr; rc = nvs_prev_ate(fs, &wlk_addr, &second_ate); if (rc) { return rc; } if (nvs_ate_valid(fs, &second_ate) && second_ate.id == last_ate.id && second_ate.expired[0] == fs->erasestate) { finfo("same id at 0x%" PRIx32 ", key_len %" PRIu16 ", " "offset %" PRIu16 "\n", second_addr, second_ate.key_len, second_ate.offset); if ((second_ate.key_len == last_ate.key_len) && !nvs_flash_direct_cmp(fs, (last_addr & ADDR_BLOCK_MASK) + last_ate.offset, (second_addr & ADDR_BLOCK_MASK) + second_ate.offset, last_ate.key_len)) { finfo("old ate found at 0x%" PRIx32 "\n", second_addr); rc = nvs_expire_ate(fs, second_addr); if (rc < 0) { ferr("expire ate failed, addr %" PRIx32 "\n", second_addr); return rc; } goto end; } else { fwarn("hash conflict\n"); } } if (wlk_addr == fs->ate_wra) { goto end; } } } } end: /* If the block is empty, add a gc done ate to avoid having insufficient * space when doing gc. */ if ((!rc) && ((fs->ate_wra & ADDR_OFFS_MASK) == (fs->blocksize - 2 * sizeof(struct nvs_ate)))) { rc = nvs_add_gc_done_ate(fs); } finfo("%" PRIu32 " Eraseblocks of %" PRIu32 " bytes\n", fs->nblocks, fs->blocksize); finfo("alloc wra: %" PRIu32 ", 0x%" PRIx32 "\n", (fs->ate_wra >> ADDR_BLOCK_SHIFT), (fs->ate_wra & ADDR_OFFS_MASK)); finfo("data wra: %" PRIu32 ", 0x%" PRIx32 "\n", (fs->data_wra >> ADDR_BLOCK_SHIFT), (fs->data_wra & ADDR_OFFS_MASK)); return rc; } /**************************************************************************** * Name: nvs_read_entry * * Description: * Read An entry from the file system. But expired ones will return * -ENOENT. * * Input Parameters: * fs - Pointer to file system. * key - Key of the entry to be read. * key_size - Size of key. * data - Pointer to data buffer. * len - Number of bytes to be read. * ate_addr - The addr of found ate. * * Returned Value: * Number of bytes read. On success, it will be equal to the number * of bytes requested to be read. When the return value is larger than the * number of bytes requested to read this indicates not all bytes were * read, and more data is available. On error returns -ERRNO code. * ****************************************************************************/ static ssize_t nvs_read_entry(FAR struct nvs_fs *fs, FAR const uint8_t *key, size_t key_size, FAR void *data, size_t len, FAR uint32_t *ate_addr) { int rc; uint32_t wlk_addr; uint32_t rd_addr; uint32_t hist_addr; struct nvs_ate wlk_ate; uint32_t hash_id; hash_id = nvs_fnv_hash(key, key_size) % 0xfffffffd + 1; wlk_addr = fs->ate_wra; rd_addr = wlk_addr; do { rd_addr = wlk_addr; hist_addr = wlk_addr; rc = nvs_prev_ate(fs, &wlk_addr, &wlk_ate); if (rc) { ferr("Walk to previous ate failed, rc=%d\n", rc); return rc; } if ((wlk_ate.id == hash_id) && (nvs_ate_valid(fs, &wlk_ate))) { if ((wlk_ate.key_len == key_size) && (!nvs_flash_block_cmp(fs, (rd_addr & ADDR_BLOCK_MASK) + wlk_ate.offset, key, key_size))) { /* It is old or deleted, return -ENOENT */ if (wlk_ate.expired[0] != fs->erasestate) { return -ENOENT; } break; } else { fwarn("hash conflict\n"); } } if (wlk_addr == fs->ate_wra) { return -ENOENT; } } while (true); if (data && len) { rd_addr &= ADDR_BLOCK_MASK; rd_addr += wlk_ate.offset + wlk_ate.key_len; rc = nvs_flash_rd(fs, rd_addr, data, MIN(len, wlk_ate.len)); if (rc) { ferr("Data read failed, rc=%d\n", rc); return rc; } } if (ate_addr) { *ate_addr = hist_addr; } return wlk_ate.len; } /**************************************************************************** * Name: nvs_write * * Description: * Write an entry to the file system. * * Input Parameters: * fs - Pointer to file system. * pdata - Pointer to data buffer. * * Returned Value: * Number of bytes written. On success, it will be equal to the * number of bytes requested to be written. On error returns -ERRNO code. * ****************************************************************************/ static ssize_t nvs_write(FAR struct nvs_fs *fs, FAR struct config_data_s *pdata) { int rc; int gc_count; size_t data_size; size_t key_size; struct nvs_ate wlk_ate; uint32_t wlk_addr; uint32_t rd_addr; uint32_t hist_addr; uint16_t required_space = 0; bool prev_found = false; uint32_t hash_id; uint16_t block_to_write_befor_gc; #ifdef CONFIG_MTD_CONFIG_NAMED FAR const uint8_t *key; #else uint8_t key[sizeof(pdata->id) + sizeof(pdata->instance)]; #endif #ifdef CONFIG_MTD_CONFIG_NAMED key = (FAR const uint8_t *)pdata->name; key_size = strlen(pdata->name) + 1; #else memcpy(key, &pdata->id, sizeof(pdata->id)); memcpy(key + sizeof(pdata->id), &pdata->instance, sizeof(pdata->instance)); key_size = sizeof(pdata->id) + sizeof(pdata->instance); #endif /* Data now contains input data and input key, input key first. */ data_size = NVS_ALIGN_UP(key_size + pdata->len); /* The maximum data size is block size - 3 ate * where: 1 ate for data, 1 ate for block close, 1 ate for gc done. */ finfo("key_size=%zu, len=%zu, data_size = %zu\n", key_size, pdata->len, data_size); if ((data_size > (fs->blocksize - 3 * sizeof(struct nvs_ate))) || ((pdata->len > 0) && (pdata->configdata == NULL))) { return -EINVAL; } /* Calc hash id of key. */ hash_id = nvs_fnv_hash(key, key_size) % 0xfffffffd + 1; /* Find latest entry with same id. */ wlk_addr = fs->ate_wra; while (1) { rd_addr = wlk_addr; hist_addr = wlk_addr; rc = nvs_prev_ate(fs, &wlk_addr, &wlk_ate); if (rc) { return rc; } if ((wlk_ate.id == hash_id) && (nvs_ate_valid(fs, &wlk_ate))) { if ((wlk_ate.key_len == key_size) && !nvs_flash_block_cmp(fs, (rd_addr & ADDR_BLOCK_MASK) + wlk_ate.offset, key, key_size)) { prev_found = true; break; } else { fwarn("hash conflict\n"); } } if (wlk_addr == fs->ate_wra) { break; } } if (prev_found) { finfo("Previous found\n"); /* Previous entry found. */ rd_addr &= ADDR_BLOCK_MASK; if (pdata->len == 0) { /* If prev ate is expired, it is deleted. */ if (wlk_ate.expired[0] != fs->erasestate) { /* Skip delete entry as it is already the * last one. */ return 0; } else { rc = nvs_expire_ate(fs, hist_addr); if (rc < 0) { ferr("expire ate failed, addr %" PRIx32 "\n", hist_addr); return rc; } /* Delete now requires no extra space, so skip write and gc. */ finfo("nvs_delete success\n"); return 0; } } else if (pdata->len == wlk_ate.len && wlk_ate.expired[0] == fs->erasestate) { /* Do not try to compare if lengths are not equal * or prev one is deleted. * Compare the data and if equal return 0. */ rd_addr += wlk_ate.offset + wlk_ate.key_len; rc = nvs_flash_block_cmp(fs, rd_addr, pdata->configdata, pdata->len); if (rc <= 0) { return rc; } } } else { /* Skip delete entry for non-existing entry. */ if (pdata->len == 0) { return -ENOENT; } } /* Leave space for gc_done ate */ required_space = data_size + sizeof(struct nvs_ate); gc_count = 0; block_to_write_befor_gc = fs->ate_wra >> ADDR_BLOCK_SHIFT; while (1) { if (gc_count == fs->nblocks) { /* Gc'ed all blocks, no extra space will be created * by extra gc. */ return -ENOSPC; } if (fs->ate_wra >= fs->data_wra + required_space) { /* Nvs is changed after gc, we will look for the old ate. */ if (prev_found && wlk_ate.expired[0] == fs->erasestate) { finfo("prev entry exists, search for it\n"); /* If gc touched second latest ate, search for it again */ if (gc_count >= fs->nblocks - 1 - (block_to_write_befor_gc + fs->nblocks - (hist_addr >> ADDR_BLOCK_SHIFT)) % fs->nblocks) { rc = nvs_read_entry(fs, key, key_size, NULL, 0, &hist_addr); finfo("relocate for prev entry, %" PRIx32 ", " "rc %d\n", hist_addr, rc); if (rc < 0) { ferr("read prev entry failed\n"); return rc; } } } finfo("Write entry, ate_wra=0x%" PRIx32 ", " "data_wra=0x%" PRIx32 "\n", fs->ate_wra, fs->data_wra); rc = nvs_flash_wrt_entry(fs, hash_id, key, key_size, pdata->configdata, pdata->len); if (rc) { fwarn("Write entry failed\n"); return rc; } finfo("Write entry success\n"); /* Expiring the old ate if exists. * After this operation, only the latest ate is valid. * Expire the old one only if it is not deleted before(Or it is * already expired) */ if (prev_found && wlk_ate.expired[0] == fs->erasestate) { rc = nvs_expire_ate(fs, hist_addr); finfo("expir prev entry, %" PRIx32 ", rc %d\n", hist_addr, rc); if (rc < 0) { ferr("expire ate failed, addr %" PRIx32 "\n", hist_addr); return rc; } } break; } rc = nvs_block_close(fs); if (rc) { return rc; } rc = nvs_gc(fs); if (rc) { return rc; } gc_count++; finfo("Gc count=%d\n", gc_count); } finfo("nvs_write success\n"); return 0; } /**************************************************************************** * Name: nvs_delete * * Description: * Delete an entry from the file system. * * Input Parameters: * fs - Pointer to file system. * pdata - Pointer to data buffer. * * Returned Value: * 0 on success, -ERRNO errno code if error. * ****************************************************************************/ static int nvs_delete(FAR struct nvs_fs *fs, FAR struct config_data_s *pdata) { /* If user wants to operate /dev/config directly. * Set len=0 to trigger delete, so that user doesn't need to do that. */ pdata->len = 0; return nvs_write(fs, pdata); } /**************************************************************************** * Name: nvs_read * * Description: * Read an entry from the file system. * * Input Parameters: * fs - Pointer to file system. * pdata - Pointer to data buffer. * * Returned Value: * 0 on success, -ERRNO errno code if error. * ****************************************************************************/ static ssize_t nvs_read(FAR struct nvs_fs *fs, FAR struct config_data_s *pdata) { size_t key_size; ssize_t ret; #ifdef CONFIG_MTD_CONFIG_NAMED FAR const uint8_t *key; #else uint8_t key[sizeof(pdata->id) + sizeof(pdata->instance)]; #endif if (pdata == NULL) { return -EINVAL; } #ifdef CONFIG_MTD_CONFIG_NAMED key = (FAR const uint8_t *)pdata->name; key_size = strlen(pdata->name) + 1; #else memcpy(key, &pdata->id, sizeof(pdata->id)); memcpy(key + sizeof(pdata->id), &pdata->instance, sizeof(pdata->instance)); key_size = sizeof(pdata->id) + sizeof(pdata->instance); #endif ret = nvs_read_entry(fs, key, key_size, pdata->configdata, pdata->len, NULL); if (ret > 0) { pdata->len = ret; return 0; } return ret; } /**************************************************************************** * Name: nvs_next * * Description: * Get the next KV in database. * * Input Parameters: * fs - Pointer to file system. * pdata - Pointer to data buffer. * first - true if we are reading the first KV. * * Returned Value: * 0 on success, -ERRNO errno code if error. * ****************************************************************************/ static int nvs_next(FAR struct nvs_fs *fs, FAR struct config_data_s *pdata, bool first) { int rc; struct nvs_ate step_ate; uint32_t rd_addr; if (pdata == NULL || pdata->len == 0 || pdata->configdata == NULL) { return -EINVAL; } #ifdef CONFIG_MTD_CONFIG_NAMED FAR uint8_t *key = (FAR uint8_t *)pdata->name; #else uint8_t key[sizeof(pdata->id) + sizeof(pdata->instance)]; #endif if (first) { fs->step_addr = fs->ate_wra; } else { if (fs->step_addr == fs->ate_wra) { return -ENOENT; } } do { rd_addr = fs->step_addr; rc = nvs_prev_ate(fs, &(fs->step_addr), &step_ate); if (rc) { return rc; } if (nvs_ate_valid(fs, &step_ate) && step_ate.id != NVS_SPECIAL_ATE_ID && step_ate.expired[0] == fs->erasestate) { break; } if (fs->step_addr == fs->ate_wra) { return -ENOENT; } } while (true); #ifdef CONFIG_MTD_CONFIG_NAMED rc = nvs_flash_rd(fs, (rd_addr & ADDR_BLOCK_MASK) + step_ate.offset, key, MIN(step_ate.key_len, CONFIG_MTD_CONFIG_NAME_LEN)); if (rc) { ferr("Key read failed, rc=%d\n", rc); return rc; } key[CONFIG_MTD_CONFIG_NAME_LEN - 1] = 0; #else rc = nvs_flash_rd(fs, (rd_addr & ADDR_BLOCK_MASK) + step_ate.offset, key, MIN(sizeof(key), step_ate.key_len)); if (rc) { ferr("Key read failed, rc=%d\n", rc); return rc; } memcpy(&pdata->id, key, sizeof(pdata->id)); memcpy(&pdata->instance, key + sizeof(pdata->id), sizeof(pdata->instance)); #endif rc = nvs_flash_rd(fs, (rd_addr & ADDR_BLOCK_MASK) + step_ate.offset + step_ate.key_len, pdata->configdata, MIN(pdata->len, step_ate.len)); if (rc) { ferr("Value read failed, rc=%d\n", rc); return rc; } pdata->len = MIN(pdata->len, step_ate.len); return OK; } /**************************************************************************** * Name: mtdconfig_open ****************************************************************************/ static int mtdconfig_open(FAR struct file *filep) { return OK; } /**************************************************************************** * Name: mtdconfig_close ****************************************************************************/ static int mtdconfig_close(FAR struct file *filep) { return OK; } /**************************************************************************** * Name: mtdconfig_read ****************************************************************************/ static ssize_t mtdconfig_read(FAR struct file *filep, FAR char *buffer, size_t buflen) { return -ENOTSUP; } /**************************************************************************** * Name: mtdconfig_ioctl ****************************************************************************/ static int mtdconfig_ioctl(FAR struct file *filep, int cmd, unsigned long arg) { FAR struct inode *inode = filep->f_inode; FAR struct nvs_fs *fs = inode->i_private; FAR struct config_data_s *pdata = (FAR struct config_data_s *)arg; int ret = -ENOTTY; ret = nxmutex_lock(&fs->nvs_lock); if (ret < 0) { return ret; } switch (cmd) { case CFGDIOC_GETCONFIG: /* Read a nvs item. */ ret = nvs_read(fs, pdata); break; case CFGDIOC_SETCONFIG: /* Write a nvs item. */ ret = nvs_write(fs, pdata); break; case CFGDIOC_DELCONFIG: /* Delete a nvs item. */ ret = nvs_delete(fs, pdata); break; case CFGDIOC_FIRSTCONFIG: /* Get the first item. */ ret = nvs_next(fs, pdata, true); break; case CFGDIOC_NEXTCONFIG: /* Get the next item. */ ret = nvs_next(fs, pdata, false); break; case MTDIOC_BULKERASE: /* Call the MTD's ioctl for this. */ ret = MTD_IOCTL(fs->mtd, cmd, arg); if (ret >= 0) { ret = nvs_startup(fs); } break; } nxmutex_unlock(&fs->nvs_lock); return ret; } /**************************************************************************** * Name: mtdconfig_poll ****************************************************************************/ static int mtdconfig_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup) { if (setup) { poll_notify(&fds, 1, POLLIN | POLLOUT); } return OK; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: mtdconfig_register_by_path * * Description: * Register a "path" device backed by an fail-safe NVS. * ****************************************************************************/ int mtdconfig_register_by_path(FAR struct mtd_dev_s *mtd, FAR const char *path) { int ret; FAR struct nvs_fs *fs; fs = kmm_malloc(sizeof(struct nvs_fs)); if (fs == NULL) { return -ENOMEM; } /* Initialize the mtdnvs device structure */ fs->mtd = mtd; ret = nxmutex_init(&fs->nvs_lock); if (ret < 0) { ferr("ERROR: nxmutex_init failed: %d\n", ret); goto errout; } ret = nvs_startup(fs); if (ret < 0) { ferr("ERROR: nvs_init failed: %d\n", ret); goto mutex_err; } ret = register_driver(path, &g_mtdnvs_fops, 0666, fs); if (ret < 0) { ferr("ERROR: register mtd config failed: %d\n", ret); goto mutex_err; } return ret; mutex_err: nxmutex_destroy(&fs->nvs_lock); errout: kmm_free(fs); return ret; } /**************************************************************************** * Name: mtdconfig_register * * Description: * Register a /dev/config device backed by an fail-safe NVS. * ****************************************************************************/ int mtdconfig_register(FAR struct mtd_dev_s *mtd) { return mtdconfig_register_by_path(mtd, "/dev/config"); } /**************************************************************************** * Name: mtdconfig_unregister_by_path * * Description: * Unregister a MTD device backed by an fail-safe NVS. * ****************************************************************************/ int mtdconfig_unregister_by_path(FAR const char *path) { int ret; struct file file; FAR struct inode *inode; FAR struct nvs_fs *fs; ret = file_open(&file, path, O_CLOEXEC); if (ret < 0) { ferr("ERROR: open file %s err: %d\n", path, ret); return ret; } inode = file.f_inode; fs = inode->i_private; nxmutex_destroy(&fs->nvs_lock); kmm_free(fs); file_close(&file); unregister_driver(path); return OK; } /**************************************************************************** * Name: mtdconfig_unregister * * Description: * Unregister a /dev/config device backed by an fail-safe NVS. * ****************************************************************************/ int mtdconfig_unregister(void) { return mtdconfig_unregister_by_path("/dev/config"); }