/*
* Copyright (c) 2015 Nordic Semiconductor ASA
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list
* of conditions and the following disclaimer.
*
* 2. Redistributions in binary form, except as embedded into a Nordic Semiconductor ASA
* integrated circuit in a product or a software update for such product, must reproduce
* the above copyright notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of Nordic Semiconductor ASA nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific prior
* written permission.
*
* 4. This software, with or without modification, must only be used with a
* Nordic Semiconductor ASA integrated circuit.
*
* 5. Any software provided in binary or object form under this license must not be reverse
* engineered, decompiled, modified and/or disassembled.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include "fds.h"
#include "fds_config.h"
#include "fds_internal_defs.h"
#include <stdint.h>
#include <string.h>
#include <stdbool.h>
#include "fstorage.h"
#include "app_util.h"
#include "nrf_error.h"
#if defined(FDS_CRC_ENABLED)
#include "crc16.h"
#endif
static void fs_event_handler(fs_evt_t const * const evt, fs_ret_t result);
// Our fstorage configuration.
FS_REGISTER_CFG(fs_config_t fs_config) =
{
.callback = fs_event_handler,
.num_pages = FDS_PHY_PAGES,
// We register with the highest priority in order to be assigned
// the pages with the highest memory address (closest to the bootloader).
.priority = 0xFF
};
// Used to flag a record as dirty, i.e. ready for garbage collection.
static fds_tl_t const m_fds_tl_dirty =
{
.record_key = FDS_RECORD_KEY_DIRTY,
.length_words = 0xFFFF // Leave the record length field unchanged in flash.
};
// Internal status flags.
static uint8_t m_flags;
// The number of registered users and their callback functions.
static uint8_t m_users;
static fds_cb_t m_cb_table[FDS_MAX_USERS];
// The latest (largest) record ID written so far.
static uint32_t m_latest_rec_id;
// The internal queues.
static fds_op_queue_t m_op_queue;
static fds_chunk_queue_t m_chunk_queue;
// Structures used to hold informations about virtual pages.
static fds_page_t m_pages[FDS_MAX_PAGES];
static fds_swap_page_t m_swap_page;
// Garbage collection data.
static fds_gc_data_t m_gc;
static void flag_set(fds_flags_t flag)
{
CRITICAL_SECTION_ENTER();
m_flags |= flag;
CRITICAL_SECTION_EXIT();
}
static void flag_clear(fds_flags_t flag)
{
CRITICAL_SECTION_ENTER();
m_flags &= ~(flag);
CRITICAL_SECTION_EXIT();
}
static bool flag_is_set(fds_flags_t flag)
{
return (m_flags & flag);
}
static void event_send(fds_evt_t const * const p_evt)
{
for (uint32_t user = 0; user < FDS_MAX_USERS; user++)
{
if (m_cb_table[user] != NULL)
{
m_cb_table[user](p_evt);
}
}
}
static void event_prepare(fds_op_t const * const p_op, fds_evt_t * const p_evt)
{
switch (p_op->op_code)
{
case FDS_OP_INIT:
p_evt->id = FDS_EVT_INIT;
break;
case FDS_OP_WRITE:
p_evt->id = FDS_EVT_WRITE;
p_evt->write.file_id = p_op->write.header.ic.file_id;
p_evt->write.record_key = p_op->write.header.tl.record_key;
p_evt->write.record_id = p_op->write.header.record_id;
break;
case FDS_OP_UPDATE:
p_evt->id = FDS_EVT_UPDATE;
p_evt->write.file_id = p_op->write.header.ic.file_id;
p_evt->write.record_key = p_op->write.header.tl.record_key;
p_evt->write.record_id = p_op->write.header.record_id;
p_evt->write.is_record_updated = (p_op->write.step == FDS_OP_WRITE_DONE);
break;
case FDS_OP_DEL_RECORD:
p_evt->id = FDS_EVT_DEL_RECORD;
p_evt->del.file_id = p_op->del.file_id;
p_evt->del.record_key = p_op->del.record_key;
p_evt->del.record_id = p_op->del.record_to_delete;
break;
case FDS_OP_DEL_FILE:
p_evt->id = FDS_EVT_DEL_FILE;
p_evt->del.file_id = p_op->del.file_id;
p_evt->del.record_key = FDS_RECORD_KEY_DIRTY;
break;
case FDS_OP_GC:
p_evt->id = FDS_EVT_GC;
break;
default:
// Should not happen.
break;
}
}
static bool header_is_valid(fds_header_t const * const p_header)
{
return ((p_header->ic.file_id != FDS_FILE_ID_INVALID) &&
(p_header->tl.record_key != FDS_RECORD_KEY_DIRTY));
}
static bool address_is_valid(uint32_t const * const p_addr)
{
return ((p_addr != NULL) &&
(p_addr >= fs_config.p_start_addr) &&
(p_addr <= fs_config.p_end_addr) &&
(is_word_aligned(p_addr)));
}
static bool chunk_is_aligned(fds_record_chunk_t const * const p_chunk, uint32_t num_chunks)
{
for (uint32_t i = 0; i < num_chunks; i++)
{
if (!is_word_aligned(p_chunk[i].p_data))
{
return false;
}
}
return true;
}
// Reads a page tag, and determines if the page is used to store data or as swap.
static fds_page_type_t page_identify(uint32_t const * const p_page_addr)
{
if (p_page_addr[FDS_PAGE_TAG_WORD_0] != FDS_PAGE_TAG_MAGIC)
{
return FDS_PAGE_UNDEFINED;
}
switch (p_page_addr[FDS_PAGE_TAG_WORD_1])
{
case FDS_PAGE_TAG_SWAP:
return FDS_PAGE_SWAP;
case FDS_PAGE_TAG_DATA:
return FDS_PAGE_DATA;
default:
return FDS_PAGE_UNDEFINED;
}
}
static bool page_is_erased(uint32_t const * const p_page_addr)
{
for (uint32_t i = 0; i < FDS_PAGE_SIZE; i++)
{
if (*(p_page_addr + i) != FDS_ERASED_WORD)
{
return false;
}
}
return true;
}
// NOTE: Must be called from within a critical section.
static bool page_has_space(uint16_t page, uint16_t length_words)
{
length_words += m_pages[page].write_offset;
length_words += m_pages[page].words_reserved;
return (length_words < FDS_PAGE_SIZE);
}
// Given a pointer to a record, find the index of the page on which it is stored.
// Returns FDS_SUCCESS if the page is found, FDS_ERR_NOT_FOUND otherwise.
static ret_code_t page_from_record(uint16_t * const p_page, uint32_t const * const p_rec)
{
ret_code_t ret = FDS_ERR_NOT_FOUND;
CRITICAL_SECTION_ENTER();
for (uint16_t i = 0; i < FDS_MAX_PAGES; i++)
{
if ((p_rec > m_pages[i].p_addr) &&
(p_rec < m_pages[i].p_addr + FDS_PAGE_SIZE))
{
ret = FDS_SUCCESS;
*p_page = i;
break;
}
}
CRITICAL_SECTION_EXIT();
return ret;
}
// Scan a page to determine how many words have been written to it.
// This information is used to set the page write offset during initialization.
// Additionally, this function updates the latest record ID as it proceeds.
// If an invalid record header is found, the can_gc argument is set to true.
static void page_scan(uint32_t const * p_addr,
uint16_t * const words_written,
bool * const can_gc)
{
uint32_t const * const p_end_addr = p_addr + FDS_PAGE_SIZE;
bool dirty_record_found = false;
p_addr += FDS_PAGE_TAG_SIZE;
*words_written = FDS_PAGE_TAG_SIZE;
while ((p_addr < p_end_addr) && (*p_addr != FDS_ERASED_WORD))
{
// NOTE: Skip records with a dirty key or with a missing file ID.
fds_header_t const * const p_header = (fds_header_t*)p_addr;
if (!header_is_valid(p_header))
{
dirty_record_found = true;
}
else
{
// Update the latest (largest) record ID.
if (p_header->record_id > m_latest_rec_id)
{
m_latest_rec_id = p_header->record_id;
}
}
// Jump to the next record.
p_addr += (FDS_HEADER_SIZE + p_header->tl.length_words);
*words_written += (FDS_HEADER_SIZE + p_header->tl.length_words);
}
if (can_gc != NULL)
{
*can_gc = dirty_record_found;
}
}
static void page_offsets_update(fds_page_t * const p_page, uint16_t length_words)
{
p_page->write_offset += (FDS_HEADER_SIZE + length_words);
p_page->words_reserved -= (FDS_HEADER_SIZE + length_words);
}
// Tags a page as swap, i.e., reserved for GC.
static ret_code_t page_tag_write_swap()
{
// Needs to be statically allocated since it will be written to flash.
static uint32_t const page_tag_swap[] = {FDS_PAGE_TAG_MAGIC, FDS_PAGE_TAG_SWAP};
return fs_store(&fs_config, m_swap_page.p_addr, page_tag_swap, FDS_PAGE_TAG_SIZE);
}
// Tags a page as data, i.e, ready for storage.
static ret_code_t page_tag_write_data(uint32_t const * const p_page_addr)
{
// Needs to be statically allocated since it will be written to flash.
static uint32_t const page_tag_data[] = {FDS_PAGE_TAG_MAGIC, FDS_PAGE_TAG_DATA};
return fs_store(&fs_config, p_page_addr, page_tag_data, FDS_PAGE_TAG_SIZE);
}
// Reserve space on a page.
// NOTE: this function takes into the account the space required for the record header.
static ret_code_t write_space_reserve(uint16_t length_words, uint16_t * p_page)
{
bool space_reserved = false;
uint16_t const total_len_words = length_words + FDS_HEADER_SIZE;
if (total_len_words >= FDS_PAGE_SIZE - FDS_PAGE_TAG_SIZE)
{
return FDS_ERR_RECORD_TOO_LARGE;
}
CRITICAL_SECTION_ENTER();
for (uint16_t page = 0; page < FDS_MAX_PAGES; page++)
{
if ((m_pages[page].page_type == FDS_PAGE_DATA) &&
(page_has_space(page, total_len_words)))
{
space_reserved = true;
*p_page = page;
m_pages[page].words_reserved += total_len_words;
break;
}
}
CRITICAL_SECTION_EXIT();
return (space_reserved) ? FDS_SUCCESS : FDS_ERR_NO_SPACE_IN_FLASH;
}
// Undo a write_space_reserve() call.
// NOTE: Must be called within a critical section.
static void write_space_free(uint16_t length_words, uint16_t page)
{
m_pages[page].words_reserved -= (length_words + FDS_HEADER_SIZE);
}
static uint32_t record_id_new(void)
{
CRITICAL_SECTION_ENTER();
m_latest_rec_id++;
CRITICAL_SECTION_EXIT();
return m_latest_rec_id;
}
// Given a page and a record, finds the next valid record on that page. If p_record is NULL,
// search from the beginning of the page, otherwise, resume searching from the address
// pointed by p_record. Returns true if a record is found, returns false otherwise.
// If no record is found, p_record is unchanged.
static bool record_find_next(uint16_t page, uint32_t const ** p_record)
{
fds_header_t const * p_header;
uint32_t const * p_next_rec = (*p_record);
// If this is not the first invocation on this page, then jump to the next record.
// Otherwise, start searching from the beginning of the page.
if (p_next_rec != NULL)
{
p_header = ((fds_header_t*)p_next_rec);
p_next_rec += (FDS_HEADER_SIZE + p_header->tl.length_words);
}
else
{
p_next_rec = m_pages[page].p_addr + FDS_PAGE_TAG_SIZE;
}
// Read records from the page, until a valid record is found or the end of the page is
// reached. The argument p_record is only updated if a valid record is found.
while ((p_next_rec < (m_pages[page].p_addr + FDS_PAGE_SIZE) &&
*p_next_rec != FDS_ERASED_WORD))
{
p_header = (fds_header_t*)p_next_rec;
if (header_is_valid(p_header))
{
*p_record = p_next_rec;
return true;
}
else
{
// The record is not valid, jump to the next.
p_next_rec += (FDS_HEADER_SIZE + (p_header->tl.length_words));
}
}
// No more valid records on this page.
return false;
}
// Find a record given its descriptor and retrive the page in which the record is stored.
// NOTE: Do not pass NULL as an argument for p_page.
static bool record_find_by_desc(fds_record_desc_t * const p_desc, uint16_t * const p_page)
{
// If the gc_run_count field in the descriptor matches our counter, then the record has
// not been moved. If the address is valid, and the record ID matches, there is no need
// to find the record again. Only lookup the page in which the record is stored.
if ((address_is_valid(p_desc->p_record)) &&
(p_desc->gc_run_count == m_gc.run_count) &&
(p_desc->record_id == ((fds_header_t*)p_desc->p_record)->record_id))
{
return (page_from_record(p_page, p_desc->p_record) == FDS_SUCCESS);
}
// Otherwise, find the record in flash.
for (*p_page = 0; *p_page < FDS_MAX_PAGES; (*p_page)++)
{
// Set p_record to NULL to make record_find_next() search from the beginning of the page.
uint32_t const * p_record = NULL;
while (record_find_next(*p_page, &p_record))
{
fds_header_t const * const p_header = (fds_header_t*)p_record;
if (p_header->record_id == p_desc->record_id)
{
p_desc->p_record = p_record;
p_desc->gc_run_count = m_gc.run_count;
return true;
}
}
}
return false;
}
// Search for a record and return its descriptor.
// If p_file_id is NULL, only the record key will be used for matching.
// If p_record_key is NULL, only the file ID will be used for matching.
// If both are NULL, it will iterate through all records.
static ret_code_t record_find(uint16_t const * const p_file_id,
uint16_t const * const p_record_key,
fds_record_desc_t * const p_desc,
fds_find_token_t * const p_token)
{
if (!flag_is_set(FDS_FLAG_INITIALIZED))
{
return FDS_ERR_NOT_INITIALIZED;
}
if (p_desc == NULL || p_token == NULL)
{
return FDS_ERR_NULL_ARG;
}
// Begin (or resume) searching for a record.
for (; p_token->page < FDS_MAX_PAGES; p_token->page++)
{
if (m_pages[p_token->page].page_type != FDS_PAGE_DATA)
{
// Skip this page.
continue;
}
while (record_find_next(p_token->page, &p_token->p_addr))
{
fds_header_t const * const p_header = (fds_header_t*)p_token->p_addr;
// A valid record was found, check its header for a match.
if ((p_file_id != NULL) &&
(p_header->ic.file_id != *p_file_id))
{
continue;
}
if ((p_record_key != NULL) &&
(p_header->tl.record_key != *p_record_key))
{
continue;
}
// Record found; update the descriptor.
p_desc->record_id = p_header->record_id;
p_desc->p_record = p_token->p_addr;
p_desc->gc_run_count = m_gc.run_count;
return FDS_SUCCESS;
}
// We have scanned an entire page. Set the address in the token to NULL
// so that it will be updated in the next iteration.
p_token->p_addr = NULL;
}
return FDS_ERR_NOT_FOUND;
}
// Retrieve basic statistics about dirty records on a page.
static void dirty_records_stat(uint16_t page,
uint16_t * const p_dirty_records,
uint16_t * const p_word_count)
{
fds_header_t const * p_header;
uint32_t const * p_rec;
p_rec = m_pages[page].p_addr + FDS_PAGE_TAG_SIZE;
while ((p_rec < (m_pages[page].p_addr + FDS_PAGE_SIZE)) &&
(*p_rec != FDS_ERASED_WORD))
{
p_header = (fds_header_t*)p_rec;
if (!header_is_valid(p_header))
{
(*p_dirty_records) += 1;
(*p_word_count) += p_header->tl.length_words;
}
else
{
p_rec += (FDS_HEADER_SIZE + (p_header->tl.length_words));
}
}
}
// Advances one position in the queue.
// Returns true if the queue is not empty.
static bool queue_advance(void)
{
// Reset the current element.
memset(&m_op_queue.op[m_op_queue.rp], 0x00, sizeof(fds_op_t));
if (m_op_queue.count != 0)
{
// Advance in the queue, wrapping around if necessary.
m_op_queue.rp = (m_op_queue.rp + 1) % FDS_OP_QUEUE_SIZE;
m_op_queue.count--;
}
return (m_op_queue.count != 0);
}
// Given a pointer to an element in the chunk queue, computes the pointer to
// the next element in the queue. Handles wrap around.
void chunk_queue_next(fds_record_chunk_t ** pp_chunk)
{
if ((*pp_chunk) != &m_chunk_queue.chunk[FDS_CHUNK_QUEUE_SIZE - 1])
{
(*pp_chunk)++;
return;
}
*pp_chunk = &m_chunk_queue.chunk[0];
}
// Retrieve the current chunk, and advance the queue.
static void chunk_queue_get_and_advance(fds_record_chunk_t ** pp_chunk)
{
if (m_chunk_queue.count != 0)
{
// Point to the current chunk and advance the queue.
*pp_chunk = &m_chunk_queue.chunk[m_chunk_queue.rp];
m_chunk_queue.rp = (m_chunk_queue.rp + 1) % FDS_CHUNK_QUEUE_SIZE;
m_chunk_queue.count--;
}
}
static void chunk_queue_skip(fds_op_t const * const p_op)
{
if ((p_op->op_code == FDS_OP_WRITE) ||
(p_op->op_code == FDS_OP_UPDATE))
{
m_chunk_queue.rp += p_op->write.chunk_count;
m_chunk_queue.count -= p_op->write.chunk_count;
}
}
// Enqueue an operation.
static bool op_enqueue(fds_op_t const * const p_op,
uint32_t num_chunks,
fds_record_chunk_t const * const p_chunk)
{
uint32_t idx;
bool ret = false;
CRITICAL_SECTION_ENTER();
if ((m_op_queue.count <= FDS_OP_QUEUE_SIZE - 1) &&
(m_chunk_queue.count <= FDS_CHUNK_QUEUE_SIZE - num_chunks))
{
idx = (m_op_queue.count + m_op_queue.rp) % FDS_OP_QUEUE_SIZE;
m_op_queue.op[idx] = *p_op;
m_op_queue.count++;
if (num_chunks != 0)
{
idx = (m_chunk_queue.count + m_chunk_queue.rp) % FDS_CHUNK_QUEUE_SIZE;
fds_record_chunk_t * p_chunk_dst;
p_chunk_dst = &m_chunk_queue.chunk[idx];
for (uint32_t i = 0; i < num_chunks; i++)
{
*p_chunk_dst = p_chunk[i];
chunk_queue_next(&p_chunk_dst);
}
m_chunk_queue.count += num_chunks;
}
ret = true;
}
CRITICAL_SECTION_EXIT();
return ret;
}
// This function is called during initialization to setup the page structure (m_pages) and
// provide additional information regarding eventual further initialization steps.
static fds_init_opts_t pages_init()
{
uint32_t ret = NO_PAGES;
// The index of the page being initialized in m_pages[].
uint16_t page = 0;
for (uint16_t i = 0; i < FDS_VIRTUAL_PAGES; i++)
{
uint32_t const * const p_page_addr = fs_config.p_start_addr + (i * FDS_PAGE_SIZE);
fds_page_type_t const page_type = page_identify(p_page_addr);
switch (page_type)
{
case FDS_PAGE_UNDEFINED:
if (page_is_erased(p_page_addr))
{
if (m_swap_page.p_addr != NULL)
{
// If a swap page is already set, flag the page as erased (in m_pages)
// and try to tag it as data (in flash) later on during initialization.
m_pages[page].page_type = FDS_PAGE_ERASED;
m_pages[page].p_addr = p_page_addr;
m_pages[page].write_offset = FDS_PAGE_TAG_SIZE;
// This is a candidate for a potential new swap page, in case the
// current swap is going to be promoted to complete a GC instance.
m_gc.cur_page = page;
page++;
}
else
{
// If there is no swap page yet, use this one.
m_swap_page.p_addr = p_page_addr;
m_swap_page.write_offset = FDS_PAGE_TAG_SIZE;
}
ret |= PAGE_ERASED;
}
break;
case FDS_PAGE_DATA:
m_pages[page].page_type = FDS_PAGE_DATA;
m_pages[page].p_addr = p_page_addr;
// Scan the page to compute its write offset and determine whether or not the page
// can be garbage collected. Additionally, update the latest kwown record ID.
page_scan(p_page_addr, &m_pages[page].write_offset, &m_pages[page].can_gc);
ret |= PAGE_DATA;
page++;
break;
case FDS_PAGE_SWAP:
m_swap_page.p_addr = p_page_addr;
// If the swap is promoted, this offset should be kept, otherwise,
// it should be set to FDS_PAGE_TAG_SIZE.
page_scan(p_page_addr, &m_swap_page.write_offset, NULL);
ret |= (m_swap_page.write_offset == FDS_PAGE_TAG_SIZE) ?
SWAP_EMPTY : SWAP_DIRTY;
break;
default:
// Shouldn't happen.
break;
}
}
return (fds_init_opts_t)ret;
}
// Write the first part of a record header (the key and length).
static ret_code_t record_header_write_begin(fds_op_t * const p_op, uint32_t * const p_addr)
{
ret_code_t ret;
ret = fs_store(&fs_config, p_addr + FDS_OFFSET_TL,
(uint32_t*)&p_op->write.header.tl, FDS_HEADER_SIZE_TL);
// Write the record ID next.
p_op->write.step = FDS_OP_WRITE_RECORD_ID;
return (ret == FS_SUCCESS) ? FDS_SUCCESS : FDS_ERR_BUSY;
}
static ret_code_t record_header_write_id(fds_op_t * const p_op, uint32_t * const p_addr)
{
ret_code_t ret;
ret = fs_store(&fs_config, p_addr + FDS_OFFSET_ID,
(uint32_t*)&p_op->write.header.record_id, FDS_HEADER_SIZE_ID);
// If this record has zero chunk, write the last part of the header directly.
// Otherwise, write the record chunks next.
p_op->write.step = (p_op->write.chunk_count != 0) ? FDS_OP_WRITE_CHUNKS :
FDS_OP_WRITE_HEADER_FINALIZE;
return (ret == FS_SUCCESS) ? FDS_SUCCESS : FDS_ERR_BUSY;
}
static ret_code_t record_header_write_finalize(fds_op_t * const p_op, uint32_t * const p_addr)
{
ret_code_t ret;
ret = fs_store(&fs_config, p_addr + FDS_OFFSET_IC,
(uint32_t*)&p_op->write.header.ic, FDS_HEADER_SIZE_IC);
// If this is a simple write operation, then this is the last step.
// If this is an update instead, delete the old record next.
p_op->write.step = (p_op->op_code == FDS_OP_UPDATE) ? FDS_OP_WRITE_FLAG_DIRTY :
FDS_OP_WRITE_DONE;
return (ret == FS_SUCCESS) ? FDS_SUCCESS : FDS_ERR_BUSY;
}
static ret_code_t record_header_flag_dirty(uint32_t * const p_record)
{
// Flag the record as dirty.
fs_ret_t ret = fs_store(&fs_config, p_record,
(uint32_t*)&m_fds_tl_dirty, FDS_HEADER_SIZE_TL);
return (ret == FS_SUCCESS) ? FDS_SUCCESS : FDS_ERR_BUSY;
}
static ret_code_t record_find_and_delete(fds_op_t * const p_op)
{
ret_code_t ret;
uint16_t page;
fds_record_desc_t desc = {0};
desc.record_id = p_op->del.record_to_delete;
if (record_find_by_desc(&desc, &page))
{
fds_header_t const * const p_header = (fds_header_t const *)desc.p_record;
// Copy the record key and file ID, so that they can be returned in the event.
// In case this function is run as part of an update, there is no need to copy
// the file ID and record key since they are present in the header stored
// in the queue element.
p_op->del.file_id = p_header->ic.file_id;
p_op->del.record_key = p_header->tl.record_key;
// Flag the record as dirty.
ret = record_header_flag_dirty((uint32_t*)desc.p_record);
// This page can now be garbage collected.
m_pages[page].can_gc = true;
}
else
{
// The record never existed, or it has already been deleted.
ret = FDS_ERR_NOT_FOUND;
}
return ret;
}
// Finds a record within a file and flags it as dirty.
static ret_code_t file_find_and_delete(fds_op_t * const p_op)
{
ret_code_t ret;
fds_record_desc_t desc;
// This token must persist across calls.
static fds_find_token_t tok = {0};
// Pass NULL to ignore the record key.
ret = record_find(&p_op->del.file_id, NULL, &desc, &tok);
if (ret == FDS_SUCCESS)
{
// A record was found: flag it as dirty.
ret = record_header_flag_dirty((uint32_t*)desc.p_record);
// This page can now be garbage collected.
m_pages[tok.page].can_gc = true;
}
else // FDS_ERR_NOT_FOUND
{
// No more records were found. Zero the token, so that it can be reused.
memset(&tok, 0x00, sizeof(fds_find_token_t));
}
return ret;
}
// Writes a record chunk to flash and advances the chunk queue. Additionally, decrements
// the number of chunks left to write for this operation and accumulates the offset.
static ret_code_t record_write_chunk(fds_op_t * const p_op, uint32_t * const p_addr)
{
ret_code_t ret;
fds_record_chunk_t * p_chunk = NULL;
// Retrieve the next chunk to be written.
chunk_queue_get_and_advance(&p_chunk);
ret = fs_store(&fs_config, p_addr + p_op->write.chunk_offset,
p_chunk->p_data, p_chunk->length_words);
// Accumulate the offset.
p_op->write.chunk_offset += p_chunk->length_words;
// Decrement the number of chunks left to write.
// NOTE: If chunk_count is initially zero, this function is not called
// because this step is skipped entirely. See record_header_write_id().
p_op->write.chunk_count--;
if (p_op->write.chunk_count == 0)
{
// All record chunks have been written; write the last part of
// the record header to finalize the write operation.
p_op->write.step = FDS_OP_WRITE_HEADER_FINALIZE;
}
return (ret == NRF_SUCCESS) ? FDS_SUCCESS : FDS_ERR_BUSY;
}
#if defined(FDS_CRC_ENABLED)
static bool crc_verify_success(uint16_t crc, uint16_t len_words, uint32_t const * const p_data)
{
uint16_t computed_crc;
// The CRC is computed on the entire record, except the CRC field itself.
// The record header is 12 bytes, out of these we have to skip bytes 6 to 8 where the
// CRC itself is stored. Then we compute the CRC for the rest of the record, from byte 8 of
// the header (where the record ID begins) to the end of the record data.
computed_crc = crc16_compute((uint8_t const *)p_data, 6, NULL);
computed_crc = crc16_compute((uint8_t const *)p_data + 8,
(FDS_HEADER_SIZE_ID + len_words) * sizeof(uint32_t),
&computed_crc);
return (computed_crc == crc);
}
#endif
static void gc_init(void)
{
m_gc.run_count++;
m_gc.cur_page = 0;
m_gc.resume = false;
// Setup which pages to GC. Defer checking for open records and the can_gc flag,
// as other operations might change those while GC is running.
for (uint16_t i = 0; i < FDS_MAX_PAGES; i++)
{
m_gc.do_gc_page[i] = (m_pages[i].page_type == FDS_PAGE_DATA);
}
}
// Obtain the next page to be garbage collected.
// Returns true if there are pages left to garbage collect, returns false otherwise.
static bool gc_page_next(uint16_t * const p_next_page)
{
bool ret = false;
for (uint16_t i = 0; i < FDS_MAX_PAGES; i++)
{
if (m_gc.do_gc_page[i])
{
// Do not attempt to GC this page again.
m_gc.do_gc_page[i] = false;
// Only GC pages with no open records and with some records which have been deleted.
if ((m_pages[i].records_open == 0) && (m_pages[i].can_gc == true))
{
*p_next_page = i;
ret = true;
break;
}
}
}
return ret;
}
static ret_code_t gc_swap_erase(void)
{
m_gc.state = GC_DISCARD_SWAP;
m_swap_page.write_offset = FDS_PAGE_TAG_SIZE;
return fs_erase(&fs_config, m_swap_page.p_addr, FDS_PHY_PAGES_IN_VPAGE);
}
// Erase the page being garbage collected, or erase the swap in case there are any open
// records on the page being garbage collected.
static ret_code_t gc_page_erase(void)
{
uint32_t ret;
uint16_t const gc = m_gc.cur_page;
if (m_pages[gc].records_open == 0)
{
ret = fs_erase(&fs_config, m_pages[gc].p_addr, FDS_PHY_PAGES_IN_VPAGE);
m_gc.state = GC_ERASE_PAGE;
}
else
{
// If there are open records, stop garbage collection on this page.
// Discard the swap and try to garbage collect another page.
ret = gc_swap_erase();
}
return ret;
}
// Copy the current record to swap.
static ret_code_t gc_record_copy(void)
{
fds_header_t const * const p_header = (fds_header_t*)m_gc.p_record_src;
uint32_t const * const p_dest = m_swap_page.p_addr + m_swap_page.write_offset;
uint16_t const record_len = FDS_HEADER_SIZE + p_header->tl.length_words;
m_gc.state = GC_COPY_RECORD;
// Copy the record to swap; it is guaranteed to fit in the destination page,
// so there is no need to check its size. This will either succeed or timeout.
return fs_store(&fs_config, p_dest, m_gc.p_record_src, record_len);
}
static ret_code_t gc_record_find_next(void)
{
ret_code_t ret;
// Find the next valid record to copy.
if (record_find_next(m_gc.cur_page, &m_gc.p_record_src))
{
ret = gc_record_copy();
}
else
{
// No more records left to copy on this page; swap pages.
ret = gc_page_erase();
}
return ret;
}
// Promote the swap by tagging it as a data page.
static ret_code_t gc_swap_promote(void)
{
m_gc.state = GC_PROMOTE_SWAP;
return page_tag_write_data(m_pages[m_gc.cur_page].p_addr);
}
// Tag the page just garbage collected as swap.
static ret_code_t gc_tag_new_swap(void)
{
m_gc.state = GC_TAG_NEW_SWAP;
m_gc.p_record_src = NULL;
return page_tag_write_swap();
}
static ret_code_t gc_next_page(void)
{
if (!gc_page_next(&m_gc.cur_page))
{
// No pages left to GC; GC has terminated. Reset the state.
m_gc.state = GC_BEGIN;
m_gc.cur_page = 0;
m_gc.p_record_src = NULL;
return FDS_OP_COMPLETED;
}
return gc_record_find_next();
}
// Update the swap page offeset after a record has been successfully copied to it.
static void gc_update_swap_offset(void)
{
fds_header_t const * const p_header = (fds_header_t*)m_gc.p_record_src;
uint16_t const record_len = FDS_HEADER_SIZE + p_header->tl.length_words;
m_swap_page.write_offset += record_len;
}
static void gc_swap_pages(void)
{
// The page being garbage collected will be the new swap page,
// and the current swap will be used as a data page (promoted).
uint32_t const * const p_addr = m_swap_page.p_addr;
m_swap_page.p_addr = m_pages[m_gc.cur_page].p_addr;
m_pages[m_gc.cur_page].p_addr = p_addr;
// Keep the offset for this page, but reset it for the swap.
m_pages[m_gc.cur_page].write_offset = m_swap_page.write_offset;
m_swap_page.write_offset = FDS_PAGE_TAG_SIZE;
}
static void gc_state_advance(void)
{
switch (m_gc.state)
{
case GC_BEGIN:
gc_init();
m_gc.state = GC_NEXT_PAGE;
break;
// A record was successfully copied.
case GC_COPY_RECORD:
gc_update_swap_offset();
m_gc.state = GC_FIND_NEXT_RECORD;
break;
// A page was successfully erased. Prepare to promote the swap.
case GC_ERASE_PAGE:
gc_swap_pages();
m_gc.state = GC_PROMOTE_SWAP;
break;
// Swap was discarded because the page being GC'ed had open records.
case GC_DISCARD_SWAP:
// Swap was sucessfully promoted.
case GC_PROMOTE_SWAP:
// Prepare to tag the page just GC'ed as swap.
m_gc.state = GC_TAG_NEW_SWAP;
break;
case GC_TAG_NEW_SWAP:
m_gc.state = GC_NEXT_PAGE;
break;
default:
// Should not happen.
break;
}
}
// Initialize the filesystem.
static ret_code_t init_execute(uint32_t prev_ret, fds_op_t * const p_op)
{
ret_code_t ret = FDS_ERR_INTERNAL;
if (prev_ret != FS_SUCCESS)
{
// A previous operation has timed out.
flag_clear(FDS_FLAG_INITIALIZING);
return FDS_ERR_OPERATION_TIMEOUT;
}
switch (p_op->init.step)
{
case FDS_OP_INIT_TAG_SWAP:
// The page write offset was determined previously by pages_init().
ret = page_tag_write_swap();
p_op->init.step = FDS_OP_INIT_TAG_DATA;
break;
case FDS_OP_INIT_TAG_DATA:
{
// Tag remaining erased pages as data.
bool write_reqd = false;
for (uint16_t i = 0; i < FDS_MAX_PAGES; i++)
{
if (m_pages[i].page_type == FDS_PAGE_ERASED)
{
ret = page_tag_write_data(m_pages[i].p_addr);
m_pages[i].page_type = FDS_PAGE_DATA;
write_reqd = true;
break;
}
}
if (!write_reqd)
{
flag_set(FDS_FLAG_INITIALIZED);
flag_clear(FDS_FLAG_INITIALIZING);
return FDS_OP_COMPLETED;
}
}
break;
case FDS_OP_INIT_ERASE_SWAP:
ret = fs_erase(&fs_config, m_swap_page.p_addr, FDS_PHY_PAGES_IN_VPAGE);
// If the swap is going to be discarded then reset its write_offset.
m_swap_page.write_offset = FDS_PAGE_TAG_SIZE;
p_op->init.step = FDS_OP_INIT_TAG_SWAP;
break;
case FDS_OP_INIT_PROMOTE_SWAP:
{
// When promoting the swap, keep the write_offset set by pages_init().
ret = page_tag_write_data(m_swap_page.p_addr);
uint16_t const gc = m_gc.cur_page;
uint32_t const * const p_old_swap = m_swap_page.p_addr;
// Execute the swap.
m_swap_page.p_addr = m_pages[gc].p_addr;
m_pages[gc].p_addr = p_old_swap;
// Copy the offset from the swap to the new page.
m_pages[gc].write_offset = m_swap_page.write_offset;
m_swap_page.write_offset = FDS_PAGE_TAG_SIZE;
m_pages[gc].page_type = FDS_PAGE_DATA;
p_op->init.step = FDS_OP_INIT_TAG_SWAP;
}
break;
default:
// Should not happen.
break;
}
if (ret != FDS_SUCCESS)
{
// fstorage queue was full.
flag_clear(FDS_FLAG_INITIALIZING);
return FDS_ERR_BUSY;
}
return FDS_OP_EXECUTING;
}
// Executes write and update operations.
static ret_code_t write_execute(uint32_t prev_ret, fds_op_t * const p_op)
{
ret_code_t ret;
uint32_t * p_write_addr;
fds_page_t * const p_page = &m_pages[p_op->write.page];
// This must persist across calls.
static fds_record_desc_t desc = {0};
if (prev_ret != FS_SUCCESS)
{
// The previous operation has timed out, update offsets.
page_offsets_update(p_page, p_op->write.header.tl.length_words);
return FDS_ERR_OPERATION_TIMEOUT;
}
// Compute the address where to write data.
p_write_addr = (uint32_t*)(p_page->p_addr + p_page->write_offset);
// Execute the current step of the operation, and set one to be executed next.
switch (p_op->write.step)
{
case FDS_OP_WRITE_FIND_RECORD:
{
// The first step of updating a record constists of locating the copy to be deleted.
// If the old copy couldn't be found for any reason then the update should fail.
// This prevents duplicates when queuing multiple updates of the same record.
uint16_t page;
desc.p_record = NULL;
desc.record_id = p_op->write.record_to_delete;
if (!record_find_by_desc(&desc, &page))
{
return FDS_ERR_NOT_FOUND;
}
// Setting the step is redundant since we are falling through.
}
// Fallthrough to FDS_OP_WRITE_HEADER_BEGIN.
case FDS_OP_WRITE_HEADER_BEGIN:
ret = record_header_write_begin(p_op, p_write_addr);
break;
case FDS_OP_WRITE_RECORD_ID:
ret = record_header_write_id(p_op, p_write_addr);
break;
case FDS_OP_WRITE_CHUNKS:
ret = record_write_chunk(p_op, p_write_addr);
break;
case FDS_OP_WRITE_HEADER_FINALIZE:
ret = record_header_write_finalize(p_op, p_write_addr);
break;
case FDS_OP_WRITE_FLAG_DIRTY:
ret = record_header_flag_dirty((uint32_t*)desc.p_record);
p_op->write.step = FDS_OP_WRITE_DONE;
break;
case FDS_OP_WRITE_DONE:
ret = FDS_OP_COMPLETED;
#if defined(FDS_CRC_ENABLED)
if (flag_is_set(FDS_FLAG_VERIFY_CRC))
{
if (!crc_verify_success(p_op->write.header.ic.crc16,
p_op->write.header.tl.length_words,
p_write_addr))
{
ret = FDS_ERR_CRC_CHECK_FAILED;
}
}
#endif
break;
default:
ret = FDS_ERR_INTERNAL;
break;
}
// An operation has either completed or failed. It may have failed because fstorage
// ran out of memory, or because the user tried to delete a record which did not exist.
if (ret != FDS_OP_EXECUTING)
{
// There won't be another callback for this operation, so update the page offset now.
page_offsets_update(p_page, p_op->write.header.tl.length_words);
}
return ret;
}
static ret_code_t delete_execute(uint32_t prev_ret, fds_op_t * const p_op)
{
ret_code_t ret;
if (prev_ret != FS_SUCCESS)
{
return FDS_ERR_OPERATION_TIMEOUT;
}
switch (p_op->del.step)
{
case FDS_OP_DEL_RECORD_FLAG_DIRTY:
ret = record_find_and_delete(p_op);
p_op->del.step = FDS_OP_DEL_DONE;
break;
case FDS_OP_DEL_FILE_FLAG_DIRTY:
ret = file_find_and_delete(p_op);
if (ret == FDS_ERR_NOT_FOUND)
{
// No more records could be found.
// There won't be another callback for this operation, so return now.
ret = FDS_OP_COMPLETED;
}
break;
case FDS_OP_DEL_DONE:
ret = FDS_OP_COMPLETED;
break;
default:
ret = FDS_ERR_INTERNAL;
break;
}
return ret;
}
static ret_code_t gc_execute(uint32_t prev_ret)
{
ret_code_t ret;
if (prev_ret != FS_SUCCESS)
{
return FDS_ERR_OPERATION_TIMEOUT;
}
if (m_gc.resume)
{
m_gc.resume = false;
}
else
{
gc_state_advance();
}
switch (m_gc.state)
{
case GC_NEXT_PAGE:
ret = gc_next_page();
break;
case GC_FIND_NEXT_RECORD:
ret = gc_record_find_next();
break;
case GC_COPY_RECORD:
ret = gc_record_copy();
break;
case GC_ERASE_PAGE:
ret = gc_page_erase();
break;
case GC_PROMOTE_SWAP:
ret = gc_swap_promote();
break;
case GC_TAG_NEW_SWAP:
ret = gc_tag_new_swap();
break;
default:
// Should not happen.
ret = FDS_ERR_INTERNAL;
break;
}
// Either FDS_OP_EXECUTING, FDS_OP_COMPLETED, FDS_ERR_BUSY or FDS_ERR_INTERNAL.
return ret;
}
static void queue_process(fs_ret_t result)
{
ret_code_t ret;
fds_op_t * const p_op = &m_op_queue.op[m_op_queue.rp];
switch (p_op->op_code)
{
case FDS_OP_INIT:
ret = init_execute(result, p_op);
break;
case FDS_OP_WRITE:
case FDS_OP_UPDATE:
ret = write_execute(result, p_op);
break;
case FDS_OP_DEL_RECORD:
case FDS_OP_DEL_FILE:
ret = delete_execute(result, p_op);
break;
case FDS_OP_GC:
ret = gc_execute(result);
break;
default:
ret = FDS_ERR_INTERNAL;
break;
}
if (ret != FDS_OP_EXECUTING)
{
fds_evt_t evt;
if (ret == FDS_OP_COMPLETED)
{
evt.result = FDS_SUCCESS;
}
else
{
// Either FDS_ERR_BUSY, FDS_ERR_OPERATION_TIMEOUT,
// FDS_ERR_CRC_CHECK_FAILED or FDS_ERR_NOT_FOUND.
evt.result = ret;
// If this operation had any chunks in the queue, skip them.
chunk_queue_skip(p_op);
}
event_prepare(p_op, &evt);
event_send(&evt);
// Advance the queue, and if there are any queued operations, process them.
if (queue_advance())
{
queue_process(FS_SUCCESS);
}
else
{
// No more elements in the queue. Clear the FDS_FLAG_PROCESSING flag,
// so that new operation can start processing the queue.
flag_clear(FDS_FLAG_PROCESSING);
}
}
}
static void queue_start(void)
{
if (!flag_is_set(FDS_FLAG_PROCESSING))
{
flag_set(FDS_FLAG_PROCESSING);
queue_process(FS_SUCCESS);
}
}
static void fs_event_handler(fs_evt_t const * const p_evt, fs_ret_t result)
{
queue_process(result);
}
// Enqueues write and update operations.
static ret_code_t write_enqueue(fds_record_desc_t * const p_desc,
fds_record_t const * const p_record,
fds_reserve_token_t const * const p_tok,
fds_op_code_t op_code)
{
ret_code_t ret;
fds_op_t op;
uint16_t page;
uint16_t crc = 0;
uint16_t length_words = 0;
if (!flag_is_set(FDS_FLAG_INITIALIZED))
{
return FDS_ERR_NOT_INITIALIZED;
}
if (p_record == NULL)
{
return FDS_ERR_NULL_ARG;
}
if ((p_record->file_id == FDS_FILE_ID_INVALID) ||
(p_record->key == FDS_RECORD_KEY_DIRTY))
{
return FDS_ERR_INVALID_ARG;
}
if (!chunk_is_aligned(p_record->data.p_chunks,
p_record->data.num_chunks))
{
return FDS_ERR_UNALIGNED_ADDR;
}
// No space was previously reserved for this operation.
if (p_tok == NULL)
{
// Compute the total length of the record.
for (uint32_t i = 0; i < p_record->data.num_chunks; i++)
{
length_words += p_record->data.p_chunks[i].length_words;
}
// Find a page where to write data.
ret = write_space_reserve(length_words, &page);
if (ret != FDS_SUCCESS)
{
// There is either not enough flash space available (FDS_ERR_NO_SPACE_IN_FLASH) or
// the record exceeds the virtual page size (FDS_ERR_RECORD_TOO_LARGE).
return ret;
}
}
else
{
page = p_tok->page;
length_words = p_tok->length_words;
}
// Initialize the operation.
op.op_code = op_code;
op.write.step = FDS_OP_WRITE_HEADER_BEGIN;
op.write.page = page;
op.write.chunk_count = p_record->data.num_chunks;
op.write.chunk_offset = FDS_OFFSET_DATA;
op.write.header.record_id = record_id_new();
op.write.header.ic.file_id = p_record->file_id;
op.write.header.tl.record_key = p_record->key;
op.write.header.tl.length_words = length_words;
if (op_code == FDS_OP_UPDATE)
{
op.write.step = FDS_OP_WRITE_FIND_RECORD;
// Save the record ID of the record to be updated.
op.write.record_to_delete = p_desc->record_id;
}
#if defined (FDS_CRC_ENABLED)
// First, compute the CRC for the first 6 bytes of the header which contain the
// record key, length and file ID, then, compute the CRC of the record ID (4 bytes).
crc = crc16_compute((uint8_t*)&op.write.header, 6, NULL);
crc = crc16_compute((uint8_t*)&op.write.header.record_id, 4, &crc);
for (uint32_t i = 0; i < p_record->data.num_chunks; i++)
{
// Compute the CRC for the record data.
crc = crc16_compute((uint8_t*)p_record->data.p_chunks[i].p_data,
p_record->data.p_chunks[i].length_words * sizeof(uint32_t), &crc);
}
#endif
op.write.header.ic.crc16 = crc;
// Attempt to enqueue the operation.
if (!op_enqueue(&op, p_record->data.num_chunks, p_record->data.p_chunks))
{
// No space availble in the queues. Cancel the reservation of flash space.
CRITICAL_SECTION_ENTER();
write_space_free(length_words, page);
CRITICAL_SECTION_EXIT();
return FDS_ERR_NO_SPACE_IN_QUEUES;
}
// Initialize the record descriptor, if provided.
if (p_desc != NULL)
{
p_desc->p_record = NULL;
// Don't invoke record_id_new() again !
p_desc->record_id = op.write.header.record_id;
p_desc->record_is_open = false;
p_desc->gc_run_count = m_gc.run_count;
}
// Start processing the queue, if necessary.
queue_start();
return FDS_SUCCESS;
}
ret_code_t fds_register(fds_cb_t cb)
{
ret_code_t ret;
CRITICAL_SECTION_ENTER();
if (m_users == FDS_MAX_USERS)
{
ret = FDS_ERR_USER_LIMIT_REACHED;
}
else
{
m_cb_table[m_users] = cb;
m_users++;
ret = FDS_SUCCESS;
}
CRITICAL_SECTION_EXIT();
return ret;
}
ret_code_t fds_init(void)
{
fds_evt_t const evt_success = { .id = FDS_EVT_INIT, .result = FDS_SUCCESS };
// No initialization is necessary. Notify the application immediately.
if (flag_is_set(FDS_FLAG_INITIALIZED))
{
event_send(&evt_success);
return FDS_SUCCESS;
}
if (flag_is_set(FDS_FLAG_INITIALIZING))
{
return FDS_SUCCESS;
}
flag_set(FDS_FLAG_INITIALIZING);
(void)fs_init();
// Initialize the page structure (m_pages), and determine which
// initialization steps are required given the current state of the filesystem.
fds_init_opts_t init_opts = pages_init();
if (init_opts == NO_PAGES)
{
return FDS_ERR_NO_PAGES;
}
if (init_opts == ALREADY_INSTALLED)
{
// No initialization is necessary. Notify the application immediately.
flag_set(FDS_FLAG_INITIALIZED);
flag_clear(FDS_FLAG_INITIALIZING);
event_send(&evt_success);
return FDS_SUCCESS;
}
fds_op_t op;
op.op_code = FDS_OP_INIT;
switch (init_opts)
{
case FRESH_INSTALL:
case TAG_SWAP:
op.init.step = FDS_OP_INIT_TAG_SWAP;
break;
case PROMOTE_SWAP:
case PROMOTE_SWAP_INST:
op.init.step = FDS_OP_INIT_PROMOTE_SWAP;
break;
case DISCARD_SWAP:
op.init.step = FDS_OP_INIT_ERASE_SWAP;
break;
case TAG_DATA:
case TAG_DATA_INST:
op.init.step = FDS_OP_INIT_TAG_DATA;
break;
default:
// Should not happen.
break;
}
// This cannot fail since it will be the first operation in the queue.
(void)op_enqueue(&op, 0, NULL);
queue_start();
return FDS_SUCCESS;
}
ret_code_t fds_record_open(fds_record_desc_t * const p_desc,
fds_flash_record_t * const p_flash_rec)
{
uint16_t page;
if ((p_desc == NULL) || (p_flash_rec == NULL))
{
return FDS_ERR_NULL_ARG;
}
// Find the record if necessary.
if (record_find_by_desc(p_desc, &page))
{
fds_header_t const * const p_header = (fds_header_t*)p_desc->p_record;
#if defined(FDS_CRC_ENABLED)
if (!crc_verify_success(p_header->ic.crc16,
p_header->tl.length_words,
p_desc->p_record))
{
return FDS_ERR_CRC_CHECK_FAILED;
}
#endif
CRITICAL_SECTION_ENTER();
m_pages[page].records_open++;
CRITICAL_SECTION_EXIT();
// Initialize p_flash_rec.
p_flash_rec->p_header = p_header;
p_flash_rec->p_data = (p_desc->p_record + FDS_HEADER_SIZE);
// Set the record as open in the descriptor.
p_desc->record_is_open = true;
return FDS_SUCCESS;
}
// The record could not be found.
// It either never existed or it has been deleted.
return FDS_ERR_NOT_FOUND;
}
ret_code_t fds_record_close(fds_record_desc_t * const p_desc)
{
ret_code_t ret;
uint16_t page;
if (p_desc == NULL)
{
return FDS_ERR_NULL_ARG;
}
if (record_find_by_desc((fds_record_desc_t*)p_desc, &page))
{
CRITICAL_SECTION_ENTER();
if ((m_pages[page].records_open > 0) && (p_desc->record_is_open))
{
m_pages[page].records_open--;
p_desc->record_is_open = false;
ret = FDS_SUCCESS;
}
else
{
ret = FDS_ERR_NO_OPEN_RECORDS;
}
CRITICAL_SECTION_EXIT();
}
else
{
ret = FDS_ERR_NOT_FOUND;
}
return ret;
}
ret_code_t fds_reserve(fds_reserve_token_t * const p_tok, uint16_t length_words)
{
ret_code_t ret;
uint16_t page;
if (!flag_is_set(FDS_FLAG_INITIALIZED))
{
return FDS_ERR_NOT_INITIALIZED;
}
if (p_tok == NULL)
{
return FDS_ERR_NULL_ARG;
}
ret = write_space_reserve(length_words, &page);
if (ret == FDS_SUCCESS)
{
p_tok->page = page;
p_tok->length_words = length_words;
}
return ret;
}
ret_code_t fds_reserve_cancel(fds_reserve_token_t * const p_tok)
{
ret_code_t ret;
if (!flag_is_set(FDS_FLAG_INITIALIZED))
{
return FDS_ERR_NOT_INITIALIZED;
}
if (p_tok == NULL)
{
return FDS_ERR_NULL_ARG;
}
if (p_tok->page > FDS_MAX_PAGES)
{
// The page does not exist. This shouldn't happen.
return FDS_ERR_INVALID_ARG;
}
fds_page_t const * const p_page = &m_pages[p_tok->page];
CRITICAL_SECTION_ENTER();
if (p_page->words_reserved - (FDS_HEADER_SIZE + p_tok->length_words) >= 0)
{
// Free reserved space.
write_space_free(p_tok->length_words, p_tok->page);
// Clean the token.
p_tok->page = 0;
p_tok->length_words = 0;
ret = FDS_SUCCESS;
}
else
{
// We are trying to cancel a reservation of more words than how many are
// currently reserved on the page. Clearly, this shouldn't happen.
ret = FDS_ERR_INVALID_ARG;
}
CRITICAL_SECTION_EXIT();
return ret;
}
ret_code_t fds_record_write(fds_record_desc_t * const p_desc,
fds_record_t const * const p_record)
{
return write_enqueue(p_desc, p_record, NULL, FDS_OP_WRITE);
}
ret_code_t fds_record_write_reserved(fds_record_desc_t * const p_desc,
fds_record_t const * const p_record,
fds_reserve_token_t const * const p_tok)
{
// A NULL token is not allowed when writing to a reserved space.
if (p_tok == NULL)
{
return FDS_ERR_NULL_ARG;
}
return write_enqueue(p_desc, p_record, p_tok, FDS_OP_WRITE);
}
ret_code_t fds_record_update(fds_record_desc_t * const p_desc,
fds_record_t const * const p_record)
{
// A NULL descriptor is not allowed when updating a record.
if (p_desc == NULL)
{
return FDS_ERR_NULL_ARG;
}
return write_enqueue(p_desc, p_record, NULL, FDS_OP_UPDATE);
}
ret_code_t fds_record_delete(fds_record_desc_t * const p_desc)
{
fds_op_t op;
if (!flag_is_set(FDS_FLAG_INITIALIZED))
{
return FDS_ERR_NOT_INITIALIZED;
}
if (p_desc == NULL)
{
return FDS_ERR_NULL_ARG;
}
op.op_code = FDS_OP_DEL_RECORD;
op.del.step = FDS_OP_DEL_RECORD_FLAG_DIRTY;
op.del.record_to_delete = p_desc->record_id;
if (op_enqueue(&op, 0, NULL))
{
queue_start();
return FDS_SUCCESS;
}
return FDS_ERR_NO_SPACE_IN_QUEUES;
}
ret_code_t fds_file_delete(uint16_t file_id)
{
fds_op_t op;
if (!flag_is_set(FDS_FLAG_INITIALIZED))
{
return FDS_ERR_NOT_INITIALIZED;
}
if (file_id == FDS_FILE_ID_INVALID)
{
return FDS_ERR_INVALID_ARG;
}
op.op_code = FDS_OP_DEL_FILE;
op.del.step = FDS_OP_DEL_FILE_FLAG_DIRTY;
op.del.file_id = file_id;
if (op_enqueue(&op, 0, NULL))
{
queue_start();
return FDS_SUCCESS;
}
return FDS_ERR_NO_SPACE_IN_QUEUES;
}
ret_code_t fds_gc(void)
{
fds_op_t op;
if (!flag_is_set(FDS_FLAG_INITIALIZED))
{
return FDS_ERR_NOT_INITIALIZED;
}
op.op_code = FDS_OP_GC;
if (op_enqueue(&op, 0, NULL))
{
if (m_gc.state != GC_BEGIN)
{
// Resume GC by retrying the last step.
m_gc.resume = true;
}
queue_start();
return FDS_SUCCESS;
}
return FDS_ERR_NO_SPACE_IN_QUEUES;
}
ret_code_t fds_record_iterate(fds_record_desc_t * const p_desc,
fds_find_token_t * const p_token)
{
return record_find(NULL, NULL, p_desc, p_token);
}
ret_code_t fds_record_find(uint16_t file_id,
uint16_t record_key,
fds_record_desc_t * const p_desc,
fds_find_token_t * const p_token)
{
return record_find(&file_id, &record_key, p_desc, p_token);
}
ret_code_t fds_record_find_by_key(uint16_t record_key,
fds_record_desc_t * const p_desc,
fds_find_token_t * const p_token)
{
return record_find(NULL, &record_key, p_desc, p_token);
}
ret_code_t fds_record_find_in_file(uint16_t file_id,
fds_record_desc_t * const p_desc,
fds_find_token_t * const p_token)
{
return record_find(&file_id, NULL, p_desc, p_token);
}
ret_code_t fds_descriptor_from_rec_id(fds_record_desc_t * const p_desc,
uint32_t record_id)
{
if (p_desc == NULL)
{
return FDS_ERR_NULL_ARG;
}
// Zero the descriptor and set the record_id field.
memset(p_desc, 0x00, sizeof(fds_record_desc_t));
p_desc->record_id = record_id;
return FDS_SUCCESS;
}
ret_code_t fds_record_id_from_desc(fds_record_desc_t const * const p_desc,
uint32_t * const p_record_id)
{
if ((p_desc == NULL) || (p_record_id == NULL))
{
return FDS_ERR_NULL_ARG;
}
*p_record_id = p_desc->record_id;
return FDS_SUCCESS;
}
ret_code_t fds_stat(fds_stat_t * const p_stat)
{
uint16_t const words_in_page = FDS_PAGE_SIZE - FDS_PAGE_TAG_SIZE;
// The largest number of free contiguous words on any page.
uint16_t contig_words = 0;
if (!flag_is_set(FDS_FLAG_INITIALIZED))
{
return FDS_ERR_NOT_INITIALIZED;
}
if (p_stat == NULL)
{
return FDS_ERR_NULL_ARG;
}
memset(p_stat, 0x00, sizeof(fds_stat_t));
for (uint16_t i = 0; i < FDS_MAX_PAGES; i++)
{
uint32_t const * p_record = NULL;
uint16_t const words_used = m_pages[i].write_offset + m_pages[i].words_reserved;
p_stat->open_records += m_pages[i].records_open;
p_stat->words_used += words_used;
contig_words = (words_in_page - words_used);
if (contig_words > p_stat->largest_contig)
{
p_stat->largest_contig = contig_words;
}
while (record_find_next(i, &p_record))
{
p_stat->valid_records++;
}
dirty_records_stat(i, &p_stat->dirty_records, &p_stat->freeable_words);
}
return FDS_SUCCESS;
}
#if defined(FDS_CRC_ENABLED)
ret_code_t fds_verify_crc_on_writes(bool enable)
{
if (enable)
{
flag_set(FDS_FLAG_VERIFY_CRC);
}
else
{
flag_clear(FDS_FLAG_VERIFY_CRC);
}
return FDS_SUCCESS;
}
#endif
